sábado, 15 de julho de 2017
sexta-feira, 14 de julho de 2017
Vegetable coloring agent lutein may suppress inflammation
Date: July 5, 2017
Source: Linköping University
Summary:
Lutein, a nutrient found in several highly colored vegetables and fruits, can suppress inflammation, according to a new study. The results suggest that lutein itself has anti-inflammatory effects in patients with coronary artery disease.
Lutein, a nutrient found in several highly coloured vegetables and fruits, can suppress inflammation, according to a new study by researchers at Linkoping University, Sweden. The results, published in Atherosclerosis, suggest that lutein itself has anti-inflammatory effects in patients with coronary artery disease.
Inflammation is a key factor in many types of coronary artery disease, such as myocardial infarction and angina.
"A considerable number of patients who have experienced myocardial infarction still have low-level chronic inflammation in the body, even after receiving effective treatment with revascularisation, drugs and lifestyle changes. We know that chronic inflammation is associated with a poorer prognosis," says Lena Jonasson, professor in the Department of Medical and Health Sciences and consultant in cardiology, who has led the study.
Previous research has suggested that our diet influences inflammatory processes in the body. One group of substances that may be interesting are the carotenoids, a large family of fat-soluble natural colouring agents found in plants. Beta-carotene and lycopene are among the more well-known substances in the family. Several previous studies have shown that the levels of carotenoids are inversely correlated with inflammation markers. The question has thus arisen whether carotenoids themselves have anti-inflammatory effects.
Most previous studies into the relationship between carotenoids and inflammation have been carried out on animals or healthy human volunteers. However, the cells of the immune system in people with low-level inflammation are more prone to stimulation, and may react differently than the corresponding cells in healthy people. The researchers who carried out the new study, therefore, wanted to investigate whether carotenoid has anti-inflammatory effects in patients with coronary artery disease.
"Our study confirms that one particular carotenoid, lutein, can suppress long-term inflammation in patients with coronary artery disease. We have also shown that lutein is absorbed and stored by the cells of the immune system in the blood," says Rosanna Chung, postdoc at the Department of Medical and Health Sciences at Linkoping University.
The researchers started by measuring the levels of the six most common carotenoids in blood from 193 patients with coronary artery disease. At the same time, they measured the level of inflammation in the blood using the inflammatory marker interleukin-6, IL-6. Lutein was the only carotenoid whose level was correlated with IL-6. The higher the level of lutein in the blood, the lower the level of IL-6.
"The patients were receiving the best possible treatment for their disease according to clinical guidelines, but even so, many of them had a persistent inflammation. At the same time, the patients had lower levels of lutein," says Lena Jonasson.
This led the researchers to investigate whether lutein can influence the cells in the blood that are involved in inflammatory processes. They collected cells of the immune system from blood from patients with coronary artery disease. They found that the inflammatory activity of the cells became significantly lower when they were treated with lutein.
The researchers now plan to investigate whether increased intake of food rich in lutein has a positive effect on the immune system in patients with coronary artery disease. Vegetables with dark-green leaves, such as spinach, are particularly rich in lutein.
Story Source:
Materials provided by Linköping University. Note: Content may be edited for style and length.
Journal Reference:
Rosanna W.S. Chung, Per Leanderson, Anna K. Lundberg, Lena Jonasson. Lutein exerts anti-inflammatory effects in patients with coronary artery disease. Atherosclerosis, 2017; 262: 87 DOI: 10.1016/j.atherosclerosis.2017.05.008
Cite This Page:
Linköping University. "Vegetable coloring agent lutein may suppress inflammation." ScienceDaily. ScienceDaily, 5 July 2017. <www.sciencedaily.com/releases/2017/07/170705105257.htm>.
Vitamin D may improve sunburn, according to new clinical trial
Results show high doses of vitamin D reduce swelling, inflammation
Date: July 6, 2017
Source: Case Western Reserve University
Summary:
High doses of vitamin D taken one hour after sunburn significantly reduce skin redness, swelling, and inflammation, according to double-blinded, placebo-controlled clinical trial.
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Cranberries may aid the gut microbiome, food scientists find
First evidence that a beneficial gut bacterium can grow when fed a carbohydrate in cranberries
Date: July 10, 2017
Source: University of Massachusetts at Amherst
Summary:
Many scientists are paying new attention to prebiotics, that is, molecules we eat but cannot digest, because some may promote the growth and health of beneficial microorganisms in our intestines, says a nutritional microbiologist. In a new study, he and colleagues report the first evidence that certain beneficial gut bacteria are able to grow when fed a carbohydrate found in cranberries and further, that they exhibit a special nontypical metabolism.
Many scientists are paying new attention to prebiotics, that is, molecules we eat but cannot digest, because some may promote the growth and health of beneficial microorganisms in our intestines, says nutritional microbiologist David Sela at the University of Massachusetts Amherst. In a new study, he and colleagues report the first evidence that certain beneficial gut bacteria are able to grow when fed a carbohydrate found in cranberries and further, that they exhibit a special nontypical metabolism.
Findings could add value to future food products or lead to a new supplement based on the cranberry, of which Massachusetts is a major producer. Details appear this week in the current early online edition of Applied and Environmental Microbiology, where the editors feature it in the "Spotlight" section that calls attention to "research articles in the upcoming issue that have been deemed of significant interest."
What we eat not only nourishes us but also feeds the beneficial bacteria, the microbiome, in our intestines, Sela points out, and food scientists are increasingly interested in these less obvious benefits of food. There are thought to be as many bacterial cells in our bodies as our own human cells, he points out, "so we're basically eating for two. These gut bacteria are extremely significant to us, they really are very important. Our food makes a difference for us as well as the beneficial microbes that we carry around with us."
Further, "a lot of plant cell walls are indigestible," he explains, "and indeed we cannot digest the special sugars found in cranberry cell walls called xyloglucans. But when we eat cranberries, the xyloglucans make their way into our intestines where beneficial bacteria can break them down into useful molecules and compounds."
Using the model beneficial bacterium bifidobacteria, Sela, an expert in the human gut microbiome, and colleagues tested the hypothesis that cranberries, a research topic at UMass Amherst for more than 60 years, might be a candidate for a new supplement to boost gut health. To obtain a supply of purified xyloglucan for these experiments, not an easy task, he enlisted help from Ocean Spray, Inc., who provided the original research material, and collaborating experts David Rowley and Jiadong Sun at the University of Rhode Island (URI).
Sela and his Ph.D. student and first author Ezgi Özcan could then feed this purified plant sugar as the only carbohydrate available to the bifidobacteria living in 96-well plates in an anaerobic environment in the laboratory.
Bifidobacteria are found in adults to some degree but the highest concentrations are found in the gut microbiome of newborn, breast-fed babies, Sela says. This study provides the first evidence that certain bifidobacteria do consume xyloglucans, and the ones that do exhibit a special metabolism that is not typical. Specifically, these bifidobacteria produce formic acid while consuming xyloglucans and less lactic acid than is typically secreted.
It is not clear yet what the impacts to health are, but the authors suspect this unusual production has implications for the rest of the microbial community in the gut. "This is not traditional food science," says Sela, a food scientist who has adjunct appointments in microbiology at UMass Amherst and in microbiology and physiological systems at UMass Medical School. The work was supported by a $64,000 grant from Ocean Spray, Inc. to Sela and $25,000 from the President's Enhancement Fund at the Graduate School of the University of Massachusetts Amherst.
Sela believes that there is stronger motivation for both researchers and consumers in studying prebiotics than probiotics. "With probiotics, we are taking extra doses of beneficial bacteria that may or may not help our gut health," he explains. "But with prebiotics, we already know that we have the beneficial guys in our guts, so let's feed them! Let's give them more nutrients and things that they like."
"They make molecules and compounds that help us, or they make it to help some of the hundreds of other kinds of beneficial members of the community. They are consuming things we can't digest, or they are helping other beneficial microbes that we find it hard to introduce as probiotics, or their presence can help keep pathogens away," he adds.
"Prebiotics and probiotics might interact with our own physiology to help balance the microbiome, and we already know that when things are not in balance you can get problems like inflammation. Underlying chronic inflammation can lead to or worsen many different medical conditions. That's the health side of this kind of study of microbiology, food and health."
He suggests that their next series of studies might look at the interaction of cranberry xyloglucans with other bacterial species and strains. Sela is also interested in other cranberry molecules interacting with bifidobacteria and other members of the gut microbiome. "We also found certain genes turned on that are consistent with xyloglucan metabolism," Sela notes. "This is another good place to pursue our findings further."
Story Source:
Materials provided by University of Massachusetts at Amherst. Note: Content may be edited for style and length.
Journal Reference:
Ezgi Özcan, Jiadong Sun, David C. Rowley, David A. Sela. A human gut commensal ferments cranberry carbohydrates to produce formate. Applied and Environmental Microbiology, 2017; AEM.01097-17 DOI: 10.1128/AEM.01097-17
Cite This Page:
University of Massachusetts at Amherst. "Cranberries may aid the gut microbiome, food scientists find: First evidence that a beneficial gut bacterium can grow when fed a carbohydrate in cranberries." ScienceDaily. ScienceDaily, 10 July 2017. <www.sciencedaily.com/releases/2017/07/170710113546.htm>.
Natural plant compound may reduce mental effects of aging, more evidence shows
Date: July 10, 2017
Source: Salk Institute
Summary:
The benefits of antioxidant fisetin have been demonstrated in mouse model of premature aging, Alzheimer's disease.
Salk scientists find benefits of antioxidant fisetin in mouse model of premature aging, Alzheimer's disease. Pamela Maher is pictured.
Credit: Salk Institute
Salk scientists have found further evidence that a natural compound in strawberries reduces cognitive deficits and inflammation associated with aging in mice. The work, which appeared in the Journals of Gerontology Series A in June 2017, builds on the team's previous research into the antioxidant fisetin, finding it could help treat age-related mental decline and conditions like Alzheimer's or stroke.
"Companies have put fisetin into various health products but there hasn't been enough serious testing of the compound," says Pamela Maher, a senior staff scientist in Salk's Cellular Neurobiology Laboratory and senior author of the paper. "Based on our ongoing work, we think fisetin might be helpful as a preventative for many age-associated neurodegenerative diseases, not just Alzheimer's, and we'd like to encourage more rigorous study of it."
Maher, who works in the lab of David Schubert, the head of Salk's Cellular Neurobiology Lab, has been studying fisetin for over a decade. Previous research by the lab found that fisetin reduced memory loss related to Alzheimer's in mice genetically modified to develop the disease. But that study focused on genetic (familial) AD, which accounts for only 1 to 3 percent of cases. By far the bigger risk factor for developing what is termed sporadic AD, as well as other neurodegenerative disorders, is simply age. For the current inquiry, Maher turned to a strain of laboratory mice that age prematurely to better study sporadic AD. By 10 months of age, these mice typically show signs of physical and cognitive decline not seen in normal mice until two years of age.
The Salk team fed the 3-month-old prematurely aging mice a daily dose of fisetin with their food for 7 months. Another group of the prematurely aging mice was fed the same food without fisetin. During the study period, mice took various activity and memory tests. The team also examined levels of specific proteins in the mice related to brain function, responses to stress and inflammation.
"At 10 months, the differences between these two groups were striking," says Maher. Mice not treated with fisetin had difficulties with all the cognitive tests as well as elevated markers of stress and inflammation. Brain cells called astrocytes and microglia, which are normally anti-inflammatory, were now driving rampant inflammation. Mice treated with fisetin, on the other hand, were not noticeably different in behavior, cognitive ability or inflammatory markers at 10 months than a group of untreated 3-month-old mice with the same condition. Additionally, the team found no evidence of acute toxicity in the fisetin-treated mice, even at high doses of the compound.
"Mice are not people, of course," says Maher, "But there are enough similarities that we think fisetin warrants a closer look, not only for potentially treating sporadic AD but also for reducing some of the cognitive effects associated with aging, generally."
Next, Maher hopes to partner with another group or company in order to conduct clinical trials of fisetin with human subjects.
Story Source:
Materials provided by Salk Institute. Note: Content may be edited for style and length.
Journal Reference:
Antonio Currais, Catherine Farrokhi, Richard Dargusch, Aaron Armando, Oswald Quehenberger, David Schubert, Pamela Maher. Fisetin Reduces the Impact of Aging on Behavior and Physiology in the Rapidly Aging SAMP8 Mouse. The Journals of Gerontology: Series A, 2017; DOI: 10.1093/gerona/glx104
Cite This Page:
Salk Institute. "Natural plant compound may reduce mental effects of aging, more evidence shows." ScienceDaily. ScienceDaily, 10 July 2017. <www.sciencedaily.com/releases/2017/07/170710160954.htm>.
Drinking coffee could lead to a longer life, scientist says
Whether it's caffeinated or decaffeinated, coffee is associated with lower mortality, which suggests the association is not tied to caffeine
Date: July 10, 2017
Source: University of Southern California
Summary:
Scientists have found that people who drink coffee appear to live longer. Drinking coffee was associated with lower risk of death due to heart disease, cancer, stroke, diabetes, and kidney disease. People who consumed a cup of coffee a day were 12 percent less likely to die compared to those who didn't drink coffee. This association was even stronger for those who drank two to three cups a day -- 18 percent reduced chance of death.
People who drink coffee live longer, new research suggests.
Credit: © iko / Fotolia
Here's another reason to start the day with a cup of joe: Scientists have found that people who drink coffee appear to live longer.
Drinking coffee was associated with a lower risk of death due to heart disease, cancer, stroke, diabetes, and respiratory and kidney disease for African-Americans, Japanese-Americans, Latinos and whites.
People who consumed a cup of coffee a day were 12 percent less likely to die compared to those who didn't drink coffee. This association was even stronger for those who drank two to three cups a day -- 18 percent reduced chance of death.
Lower mortality was present regardless of whether people drank regular or decaffeinated coffee, suggesting the association is not tied to caffeine, said Veronica W. Setiawan, lead author of the study and an associate professor of preventive medicine at the Keck School of Medicine of USC.
"We cannot say drinking coffee will prolong your life, but we see an association," Setiawan said. "If you like to drink coffee, drink up! If you're not a coffee drinker, then you need to consider if you should start."
The study, which will be published in the July 11 issue of Annals of Internal Medicine, used data from the Multiethnic Cohort Study, a collaborative effort between the University of Hawaii Cancer Center and the Keck School of Medicine.
The ongoing Multiethnic Cohort Study has more than 215,000 participants and bills itself as the most ethnically diverse study examining lifestyle risk factors that may lead to cancer.
"Until now, few data have been available on the association between coffee consumption and mortality in nonwhites in the United States and elsewhere," the study stated. "Such investigations are important because lifestyle patterns and disease risks can vary substantially across racial and ethnic backgrounds, and findings in one group may not necessarily apply to others."
Since the association was seen in four different ethnicities, Setiawan said it is safe to say the results apply to other groups.
"This study is the largest of its kind and includes minorities who have very different lifestyles," Setiawan said. "Seeing a similar pattern across different populations gives stronger biological backing to the argument that coffee is good for you whether you are white, African-American, Latino or Asian."
Benefits of drinking coffee
Previous research by USC and others have indicated that drinking coffee is associated with reduced risk of several types of cancer, diabetes, liver disease, Parkinson's disease, Type 2 diabetes and other chronic diseases.
Setiawan, who drinks one to two cups of coffee daily, said any positive effects from drinking coffee are far-reaching because of the number of people who enjoy or rely on the beverage every day.
"Coffee contains a lot of antioxidants and phenolic compounds that play an important role in cancer prevention," Setiawan said. "Although this study does not show causation or point to what chemicals in coffee may have this 'elixir effect,' it is clear that coffee can be incorporated into a healthy diet and lifestyle."
About 62 percent of Americans drink coffee daily, a 5 percent increase from 2016 numbers, reported the National Coffee Association.
As a research institution, USC has scientists from across disciplines working to find a cure for cancer and better ways for people to manage the disease.
The Keck School of Medicine and USC Norris Comprehensive Cancer Center manage a state-mandated database called the Los Angeles Cancer Surveillance Program, which provides scientists with essential statistics on cancer for a diverse population.
Researchers from the USC Norris Comprehensive Cancer Center have found that drinking coffee lowers the risk of colorectal cancer.
But drinking piping hot coffee or beverages probably causes cancer in the esophagus, according to a World Health Organization panel of scientists that included Mariana Stern from the Keck School of Medicine.
Hearing from the WHO
In some respects, coffee is regaining its honor for wellness benefits. After 25 years of labeling coffee a carcinogen linked to bladder cancer, the World Health Organization last year announced that drinking coffee reduces the risk for liver and uterine cancer.
"Some people worry drinking coffee can be bad for you because it might increase the risk of heart disease, stunt growth or lead to stomach ulcers and heartburn," Setiawan said. "But research on coffee have mostly shown no harm to people's health."
Coffee by the numbers
Setiawan and her colleagues examined the data of 185,855 African-Americans (17 percent), Native Hawaiians (7 percent), Japanese-Americans (29 percent), Latinos (22 percent) and whites (25 percent) ages 45 to 75 at recruitment. Participants answered questionnaires about diet, lifestyle, and family and personal medical history.
They reported their coffee drinking habits when they entered the study and updated them about every five years, checking one of nine boxes that ranged from "never or hardly ever" to "4 or more cups daily." They also reported whether they drank caffeinated or decaffeinated coffee. The average follow-up period was 16 years.
Sixteen percent of participants reported that they did not drink coffee, 31 percent drank one cup per day, 25 percent drank two to three cups per day and 7 percent drank four or more cups per day. The remaining 21 percent had irregular coffee consumption habits.
Over the course of the study, 58,397 participants -- about 31 percent -- died. Cardiovascular disease (36 percent) and cancer (31 percent) were the leading killers.
The data was adjusted for age, sex, ethnicity, smoking habits, education, preexisting disease, vigorous physical exercise and alcohol consumption.
Setiawan's previous research found that coffee reduces the risk of liver cancer and chronic liver disease. She is currently examining how coffee is associated with the risk of developing specific cancers.
Researchers from the University of Hawaii Cancer Center and the National Cancer Institute contributed to this study. The study used data from the Multiethnic Cohort Study, which is supported by a $19,008,359 grant from the National Cancer Institute of the National Institutes of Health.
Story Source:
Materials provided by University of Southern California. Note: Content may be edited for style and length.
Journal References:
Marc J. Gunter et al. Coffee Drinking and Mortality in 10 European Countries: A Multinational Cohort Study. Annals of Internal Medicine, 2017 DOI: 10.7326/M16-2945
Song-Yi Park et al. Association of Coffee Consumption With Total and Cause-Specific Mortality Among Nonwhite Populations. Annals of Internal Medicine, 2017 DOI: 10.7326/M16-2472
Cite This Page:
University of Southern California. "Drinking coffee could lead to a longer life, scientist says: Whether it's caffeinated or decaffeinated, coffee is associated with lower mortality, which suggests the association is not tied to caffeine." ScienceDaily. ScienceDaily, 10 July 2017. <www.sciencedaily.com/releases/2017/07/170710172118.htm>.
Antibiotics taken late in pregnancy can increase risk for inflammatory bowel diseases in offspring
Date: July 11, 2017
Source: University of Chicago Medical Center
Summary:
When mice that are genetically susceptible to developing inflammatory bowel disease (IBD) were given antibiotics during late pregnancy and the early nursing period, their offspring were more likely to develop an inflammatory condition of the colon that resembles human IBD, report scientists.
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Closing medical marijuana dispensaries increases crime, according to new study
Date: July 11, 2017
Source: University of California, Irvine, The Paul Merage School of Business
Summary:
Contrary to popular belief, medical marijuana dispensaries (MMDs) reduce crime in their immediate areas, suggests a new report.
A new study published in the July issue of the Journal of Urban Economics finds that contrary to popular belief, medical marijuana dispensaries (MMDs) reduce crime in their immediate areas.
In the study, titled, "Going to pot? The impact of dispensary closures on crime," researchers Tom Y. Chang from the USC Marshall School of Business, and Mireille Jacobson from The Paul Merage School of Business at UC Irvine, examined the short-term mass closing of hundreds of medical marijuana dispensaries in Los Angeles that took place in 2010.
"Contrary to popular wisdom, we found an immediate increase in crime around dispensaries ordered to close relative to those allowed to remain open," said Jacobson.
The two researchers found similar results when they examined restaurant closures.
"The connection between restaurants and MMDs is that they both contribute to the 'walkability score' of a given area. Areas with higher scores have more 'eyes upon the street' a factor that is proven to deter some types of crime," said Jacobson.
The types of crime most impacted by MMD and restaurant closures were property crime and theft from vehicles. The researchers attributed this result to the fact that these types of crimes are most plausibly deterred by bystanders.
"Our results demonstrate that the dispensaries were not the crime magnets that they were often described as, but instead reduced crime in their immediate vicinity," said Jacobson.
When Chang and Jacobson examined the impact of temporary restaurant closures in Los Angeles County, they found an increase in crime similar to what they found with MMDs. They also found that once a restaurant reopened, crime immediately disappeared.
Jacobson added, "We can conclude from our research that retail businesses are effective in lowering crime, even when the retail business is a medical marijuana dispensary."
Story Source:
Materials provided by University of California, Irvine, The Paul Merage School of Business. Note: Content may be edited for style and length.
Journal Reference:
Tom Y. Chang, Mireille Jacobson. Going to pot? The impact of dispensary closures on crime. Journal of Urban Economics, 2017; 100: 120 DOI: 10.1016/j.jue.2017.04.001
Cite This Page:
University of California, Irvine, The Paul Merage School of Business. "Closing medical marijuana dispensaries increases crime, according to new study." ScienceDaily. ScienceDaily, 11 July 2017. <www.sciencedaily.com/releases/2017/07/170711125704.htm>.
Compostos extraídos do bagaço da uva reduzem processo inflamatório (Jornal da UNICAMP)
02.03.2017
Resíduo da fruta tratado com enzima tanase tem altos valores de fenólicos bioativos
TEXTO SILVIO ANUNCIAÇÃO
FOTOS ANTONINHO PERRI
Cerca de 40% dos compostos fenólicos da uva são desprezados durante o processo de produção de vinho no Brasil. Benéficos ao organismo humano, tais compostos são descartados junto com o bagaço da fruta. Com a aplicação de uma enzima produzida em laboratório, a pesquisadora da Unicamp Isabela Mateus Martins extraiu do subproduto da indústria de sucos e vinhos maiores quantidades de fenólicos.
O estudo conduzido por ela junto à Faculdade de Engenharia de Alimentos (FEA) demonstrou ainda que os fenólicos extraídos apresentaram eficácia na redução do processo inflamatório de células intestinais (CACO-2). Os biomarcadores de inflamação reduzidos foram a prostaglandina E2 (PGE2), a interleucina 8 (IL-8) e o fator de transcrição kappa B (NF-κB).
A pesquisadora Isabela Mateus Martins, autora do estudo: tratamento enzimático eleva atividade anti-inflamatória dos compostos presentes no subproduto
A autora da pesquisa explica que processos inflamatórios prolongados no organismo podem causar disfunções fisiológicas e levar ao aparecimento de diabetes, hipertensão, obesidade, câncer e doenças inflamatórias intestinais, como a colite ulcerativa e a Doença de Crohn. “Após o tratamento com a enzima tanase em células intestinais tivemos um aumento de aproximadamente 25% na atividade anti-inflamatória do extrato obtido a partir do bagaço da uva”, revela.
Houve ainda, com o tratamento enzimático, aumento da atividade antioxidante e da quantidade de compostos fenólicos, que previnem e retardam a formação de radicais livres no organismo. A pesquisadora relata incremento de 51% na concentração de fenóis totais em comparação com a amostra sem o tratamento. “Pudemos também constatar um aumento de compostos fenólicos menores e mais simples, em especial ácido gálico, quercetina e transresveratrol”, acrescenta.
Potencial subaproveitado
A autora do estudo explica que o bagaço da uva, especialmente a tinta, é rico em compostos fenólicos bioativos. “Mas este resíduo acaba indo para o lixo ou sendo subaproveitado como adubo do solo ou incorporado em ração para animais. Nosso trabalho demonstra o potencial do bagaço que poderia ser transformado e empregado, por exemplo, na fabricação de alimentos funcionais, de suplementos e produtos para a indústria farmacêutica”, sugere.
Conforme dados coletados por Isabela Martins em seu estudo, a produção mundial de vinho e suco gera, anualmente, cerca de 13 milhões de toneladas de resíduos. No Brasil, a estimativa é que sejam gerados em torno de 150 mil toneladas por ano de bagaço de uva.
A pesquisa desenvolvida por ela integrou doutorado defendido junto ao Programa de Pós-Graduação em Ciência de Alimentos da FEA. Uma parte dos trabalhos foi conduzida no Antioxidants Research Laboratory, pertencente à Tufts University, localizada na cidade de Boston, nos Estados Unidos. Na Unicamp, a professora Gabriela Alves Macedo, do Departamento de Alimentos e Nutrição da FEA, orientou a pesquisa.
O intercâmbio da cientista da Unicamp foi financiado pelo Programa Ciência sem Fronteiras, do Governo Federal. Houve ainda apoio do Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) e da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Capes).
Uva tinta e tanase
O resíduo da uva tratado com a enzima tanase apresentou os maiores valores de compostos fenólicos bioativos quando comparado com o extrato sem o tratamento enzimático. Na comparação, o bagaço da uva tinta também indicou melhores resultados que o da branca. “Os dois extratos tiveram seu potencial antioxidante elevado após os tratamentos enzimáticos, mas o da uva tinta que recebeu o tratamento com a tanase apresentou aumento mais significativo”, compara.
A autora do estudo esclarece que apenas o extrato da uva tinta, antes e após o tratamento com a tanase, foi submetido aos testes de atividade anti-inflamatória em células intestinais. “O objetivo era escolher o extrato com o maior valor de compostos fenólicos para, então, testá-lo em células intestinais. Por este motivo só empregamos o da uva tinta.”
A pesquisadora utilizou ainda outras duas enzimas para promover a extração dos compostos fenólicos bioativos: a celulase e a pectinase. De acordo com ela, ao contrário da tanase, são enzimas bastante utilizadas pela indústria. “A tanase também se mostrou melhor nesta comparação.”
Link:
Jambo e jabuticaba fazem bem à memória e previnem contra doenças da obesidade (Jornal da UNICAMP)
14.06.2017
Pesquisa desenvolvida na Faculdade de Engenharia de Alimentos rendeu cinco artigos, dois dos quais já publicados
TEXTO LUIZ SUGIMOTO
FOTOS ANTONIO SCARPINETTI
EDIÇÃO DE IMAGEM LUIS PAULO SILVA
Uma pesquisa de doutorado da nutricionista Ângela Giovana Batista confirmou o benefício trazido pela jabuticaba e o jambo-vermelho para o aprendizado e memória em modelos animais, bem como a ação de compostos antioxidantes bioativos e fibras dessas frutas vermelhas na prevenção de doenças associadas à obesidade. A tese, orientada pelo professor Mário Roberto Maróstica Júnior, foi desenvolvida no Laboratório de Nutrição e Metabolismo, da Faculdade de Engenharia de Alimentos (FEA), e teve coorientação da professora Maria Alice da Cruz Höfling, do Laboratório de Ultraestrutura Celular, do Instituto de Biologia (IB). Até o momento, a pesquisa rendeu cinco artigos, dois deles já publicados.
A nutricionista Ângela Giovana Batista, autora da tese: primeiro passo foi avaliar a composição química das frutas
“Nosso grupo trabalha com a jabuticaba desde 2008 e, como os estudos foram mostrando efeitos benéficos da fruta, resolvemos dar sequência à linha de pesquisa”, explica Ângela Batista. “O jambo é uma fruta que não conhecíamos e que decidimos investigar por não haver nenhum relato na literatura sobre seus efeitos, sendo que a produção de um jambeiro-vermelho é muito alta no Brasil. Na época da safra, a árvore produz muito e, a não ser no Norte e Nordeste, as pessoas não consomem as frutas, talvez por desconhecimento.”
Segundo a nutricionista, o jambo-vermelho é típico das regiões quentes, como de Araçatuba, onde ela colheu as amostras para a pesquisa. “Eu consumi a fruta in natura e seu sabor é ácido-adocicado, leve, parecido com o da maçã – as do Norte e Nordeste devem ter gosto diferente. O interessante é seu cheiro, é uma fruta que cheira a rosas. O jambo mostrou em sua composição quantidades expressivas de fibras e polifenóis, com destaque para antocianinas, que são compostos associados a propriedades benéficas contra doenças metabólicas.”
Ângela explica que o primeiro passo foi avaliar a composição química da jabuticaba e do jambo, pois a cada ano, e dependendo também da região, a sua composição vai se alterando. “A planta produz esses compostos bioativos (antioxidantes) para se defender dos efeitos de um clima indesejado para ela e, conforme o clima muda, ela apresenta quantidades diferentes destes compostos. Foi conforme a composição que formulamos as dietas hiperlipídicas para os animais, utilizando a banha de porco para melhor simular o que é consumido em termos de gordura nesses tempos de fast foods.”
Durante os ensaios biológicos, os camundongos passaram dez semanas consumindo dietas com baixa e alta concentração de gordura, suplementadas com a casca de jabuticaba e a polpa de jambo-vermelho. “Após esse tratamento, os animais mostraram melhoras em marcadores de obesidade, como diminuição da massa corporal gorda, maior resistência à insulina periférica, redução de marcadores pró-inflamatórios e aumento da defesa antioxidante (que combate os radicais livres do organismo). Todos esses parâmetros estão associados com a prevenção de diabetes tipo 2 – um problema de saúde pública de grande escala no Brasil e no mundo.”
Teste do labirinto
Ângela Batista considera que um aspecto inédito de sua tese foi a investigação do papel da jabuticaba e do jambo na memória dos animais. “No início das pesquisas, observamos que o hipocampo, que comanda a memória e o aprendizado (e uma das primeiras regiões do cérebro a ser afetada quando a doença de Alzheimer se inicia), sofria dano oxidativo devido à alta produção de radicais livres após o consumo de dieta gordurosa, além de não responder de forma adequada à sinalização da insulina nas células, promovendo a fosforilação de uma proteína chamada Tau.”
Trocando em miúdos, a nutricionista explica que a Tau é responsável pela polimerização de microtúbulos, contribuindo para manter a estrutura dos neurônios e principalmente dos axônios. “Quando fosforilada em vários sítios, a Tau se separa dos microtúbulos, e se associa formando emaranhados neurofibrilares. Esses emaranhados prejudicam a plasticidade neuronal e, assim, os neurônios perdem suas conexões e sinapses, ficando impedidos de executar tarefas de acesso e aquisição da memória. A suplementação da dieta gordurosa com ambas as frutas (jambo-vermelho e jabuticaba) não só prevenia esse dano, como aumentava a sensibilidade à insulina, evitando a formação de marcadores do Alzheimer como a fosforilação da Tau.”
Para confirmar os achados, acrescenta a autora da tese, os animais foram submetidos ao teste conhecido como “labirinto aquático de Morris”: durante cinco dias, eles foram treinados a encontrar uma plataforma escondida numa piscina. “No último dia, a plataforma foi retirada. Ao procurá-la, os animais que não receberam o suplemento na dieta nadavam a esmo, enquanto os que consumiram jambo e casca de jabuticaba nadavam exatamente no local onde estava a plataforma – uma brincadeira dentro do grupo era de que esses animais estavam usando GPS.”
Efeito preventivo
Ângela Batista antecipa que outros alunos do grupo de pesquisa já estão se envolvendo com a parte tecnológica da linha de pesquisa, buscando incorporar essas frutas vermelhas em produtos que cheguem rapidamente ao consumidor. “Já investigamos, por exemplo, os efeitos do chá da casca de jabuticaba e também em barra de cereais. Começamos a divulgar os nossos estudos com essa fruta em 2012 e, não sei se por coincidência, chegam notícias da utilização de sua casca para a produção de farinhas, sucos, iogurtes e sorvetes. Mas é importante salientar que tais produtos, quando viabilizados, têm efeito preventivo e não curativo.”
A crença da pesquisadora, de qualquer forma, é de que a prevenção é mesmo o melhor remédio, dando o exemplo do mal de Alzheimer, que começa a se desenvolver dez ou quinze anos antes de ser diagnosticado. “Ocorre que os marcadores do Alzheimer já estão lá – e é quando a alimentação é muito importante. Hoje as pessoas demonstram mais consciência de que ‘você é o que você come’, retomando valores da antiga medicina pregada por Hipócrates: que seu alimento seja seu medicamento.”
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Estudo testa novas técnicas para extração de compostos bioativos da quebra-pedra (Jornal da UNICAMP)
07.07.2017
Planta apresenta propriedades hepatoprotetoras, anti-inflamatórias e esquistossomicida
TEXTO MANEUL ALVES FILHO
EDIÇÃO DE IMAGEM LUIS PAULO SILVA
Estudo desenvolvido na Faculdade de Engenharia de Alimentos (FEA) da Unicamp utilizou duas diferentes técnicas [líquidos pressurizados e fluidos supercríticos] para fazer a extração de lignanas, compostos bioativos presentes na espécie Phyllanthus amarus, planta medicinal popularmente conhecida como quebra-pedra. O segundo método proporcionou o melhor resultado, tendo sido responsável pela obtenção de extratos com até 35% da substância pretendida, índice considerado muito significativo para um extrato bruto. O trabalho, orientado pelo professor Julian Martínez e coorientado pela pesquisadora Vera Lucia Garcia, do Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas (CPQBA), foi realizado no contexto da tese de doutorado do engenheiro de alimentos Rúbner Gonçalves Pereira.
O engenheiro de alimentos Rúbner Gonçalves Pereira, autor da tese: “Os métodos testados são bem interessantes porque melhoram as características dos solventes e aceleram o tempo de extração, em comparação com as técnicas convencionais”
A pesquisa conduzida por Pereira abre perspectiva para uso das lignanas na produção futura de fármacos. Segundo a literatura científica, esses compostos bioativos apresentam propriedades hepatoprotetoras, anti-inflamatórias e esquistossomicida, ou seja, atuam no combate ao parasita Schistosoma mansoni, causador da esquistossomose. “Obviamente, ainda temos um longo caminho a cumprir antes de desenvolver um fármaco a partir das lignanas. Mas já demos um passo importante”, define o autor do estudo.
De acordo com Pereira, os dois métodos testados por ele são novos em comparação com outros que vêm sendo aplicados pela indústria há várias décadas. Tanto os líquidos pressurizados quanto os fluidos supercríticos, acrescenta o pesquisador, têm sido empregados pela indústria em outros países, mas no Brasil essas técnicas por enquanto são utilizadas somente em escala laboratorial. “São tecnologias bem interessantes porque melhoram as características dos solventes e aceleram o tempo de extração, em comparação com as técnicas convencionais”, explica o autor da tese.
Dito de modo simplificado, para extrair compostos de uma planta é preciso encontrar um solvente capaz de solubilizar as substâncias de interesse. O resultado vai depender do grau de interação entre os solventes e os compostos. Com o uso dos líquidos pressurizados, informa o autor da tese, é possível modificar diversos parâmetros presentes no processo, entre eles a temperatura. “Nós testamos diversas temperaturas, até chegar àquela que proporcionou o melhor índice de extração. O mesmo foi feito com os fluidos supercríticos, mas também em relação ao parâmetro pressão”, detalha Pereira.
Ao final dos experimentos, o engenheiro de alimentos concluiu que, no caso do líquido pressurizado, a temperatura não teve influência significativa sobre a extração. Na prática, qualquer temperatura dentro do intervalo testado [35 e 80 graus célsius] pode ser aplicada para realizar a extração das lignanas. “Nesse caso, a recomendação é optar pela menor temperatura, visto que isso acarretará um menor uso de energia no processo”, pondera o pesquisador.
No que toca ao fluido supercrítico, foram analisadas diversas variáveis. A principal conclusão foi que a combinação entre menor temperatura e nível de pressão intermediário proporcionou o melhor resultado. “Nesse caso, o fluido supercrítico foi bem mais seletivo. O método permitiu a obtenção de um extrato mais rico em lignanas, com concentração de 35%. Já a técnica com uso de líquido pressurizado gerou extrato com concentração que variou de 0,2% a 4%”, revela Pereira.
A espécie Phyllanthus amarus, popularmente conhecida como quebra-pedra: custo de aquisição da planta representa maior parte do custo de produção do extrato bruto
Outra vantagem do método que utiliza o fluido supercrítico, conforme o autor da tese, é que o solvente é removido durante o processo. Com o uso do líquido pressurizado, é preciso cumprir uma etapa adicional para fazer a remoção do solvente. O engenheiro de alimentos esclarece que trabalhos anteriores envolvendo a extração de lignanas foram feitos por áreas diferentes da engenharia. Nesses casos, o foco das pesquisas não era a quantificação dos compostos, mas sim a sua atividade biológica. “Por isso, tivemos dificuldade em estabelecer comparações, mas a quantidade de lignanas que obtivemos é muito expressiva”, reforça Pereira.
Em sua tese, o pesquisador também analisou o custo dos processos da extração das lignanas. O que ele apurou foi que a aquisição das plantas e dos solventes representa 90% do custo total de produção. Desses 90%, 67% correspondem somente ao custo de aquisição da quebra-pedra. “Isso ocorre porque a planta é usada majoritariamente em caráter doméstico no Brasil. Não temos fornecedores em larga escala para a indústria. Por isso, é mais difícil encontrar essa matéria prima, que por sua vez também custa mais caro”, analisa Pereira, que contou com bolsa de estudos concedida pela Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Capes), agência de fomento do Ministério da Educação.
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Estudo revela riscos da ingestão de sucupira (Jornal da UNICAMP)
02.03.2017
TEXTO LUIZ SUGIMOTO
FOTOS ANTONIO SCARPINETTI
EDIÇÃO DE IMAGEM LUIS PAUO SILVA
O uso de plantas medicinais é frequente em muitas comunidades onde a população as utiliza de forma empírica para combater os sintomas de doenças, na forma de chás e infusões. O chá dos frutos da espécie Pterodon pubescens Benth, conhecida popularmente como sucupira, é tido como analgésico e anti-inflamatório natural. Mas também é muito comum encontrar produtos, que alegam conter sucupira, sendo oferecidos no mercado. E a população exposta ao apelo de produtos milagrosos e naturais não conhecem realmente os riscos.
A sucupira é estudada desde 1998 pelo grupo de Mary Ann Foglio, atualmente professora da Faculdade de Ciências Farmacêuticas, que desenvolveu o trabalho nas dependências do Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas (CPQBA). A união do conhecimento popular com a investigação experimental de drogas, a partir da observação do uso de plantas medicinais pelos povos, é denominada etnofarmacologia.
A farmacêutica Vanessa Helena da Silva Souza, autora da tese: avaliação dos riscos do uso terapêutico
Diante do grande número de pessoas relatando melhoras clínicas após a ingestão da infusão dos frutos da sucupira, e diante da escassez de dados consistentes sobre a segurança de sua utilização, a farmacêutica Vanessa Helena da Silva Souza desenvolveu tese de doutorado avaliando a toxicidade não clínica do extrato bruto diclorometânico (EBD), bem como de compostos isolados do extrato, a fim de verificar os riscos deste uso terapêutico.
Os estudos toxicológicos foram realizados de acordo com a legislação vigente, tendo como base o guia de orientação de condução de estudos, proposto pela Agência de Vigilância Sanitária (Anvisa), que estabelece as normas para o desenvolvimento de um medicamento fitoterápico e/ou fitofármaco. “A Anvisa preconiza os testes com animais porque a resposta que oferecem permite uma projeção de segurança no uso humano. Chamamos de análise preliminar, não clínica, com todos os testes atendendo a normas nacionais e internacionais, bem como a aspectos éticos de boas práticas de experimentação animal”, diz a farmacêutica.
As amostras dos extratos e compostos isolados foram testadas em protocolos de toxicidade aguda oral e de doses repetidas in vivo, e ainda de genotoxicidade e mutagenicidade in vitro. A tese intitulada “Avaliação da toxicidade não clínica de extrato e vouacapanos obtidos dos frutos da espécie Pterodon pubescens Benth” foi defendida no programa de pós-graduação da Faculdade de Odontologia de Piracicaba (FOP).
A professora Mary Ann Foglio, que orientou o trabalho, afirma que uma das preocupações do seu grupo de pesquisa é desmistificar a crença de que o “natural não faz mal” e, portanto, que plantas medicinais ou produtos fitoterápicos estariam isentos de riscos à saúde. “Isso faz parte da bagagem cultural da nossa população. Porém, o potencial tóxico, a diversidade de respostas fisiológicas para cada indivíduo e a possibilidade de contaminação com o desvio de qualidade de produtos, constituem fatores de risco de reações adversas, intoxicações e outras complicações decorrentes do uso indiscriminado e da falta de informações.”
Á arvore da sucupira antes (abaixo) e depois (acima) da floração
Para a professora, esta preocupação se acentua quando se constata que as mais variadas espécies de plantas, consideradas medicinais, são comercializadas livremente em mercados populares ou pela internet, com apelos de cura para quase todos os males. Existe um vasto uso de extratos de sucupira para aliviar as dores de artrite e comprimidos anunciados como dela oriundos são facilmente encontrados no mercado informal. Porém, a análise em laboratório demonstrou que vários destes produtos, na realidade, continham o princípio ativo de medicamentos como Voltaren® e Cataflam®, que é o diclofenaco utilizado no tratamento de processos inflamatórios.”
Vanessa Helena alerta que a artrite, por exemplo, é uma doença crônica, o que induziria as pessoas a fazerem uso contínuo do suposto comprimido de sucupira. “O diclofenado deve ser tomado com acompanhamento de um profissional da saúde capacitado, e geralmente por um período de sete dias, considerando que o uso prolongado pode comprometer as funções renais do indivíduo. Neste trabalho foram avaliados os riscos do uso contínuo de diferentes dosagens dos extratos e componentes extraídos da sucupira em camundongos e ratos. Esses dados científicos são importantes, pois muitos analgésicos, como o paracetamol, são altamente hepatotóxicos. Ainda assim, o paracetamol está isento de prescrição médica, sendo muito utilizado na pediatria.”
Segundo a orientadora da tese, a enorme biodiversidade vegetal é capaz de fornecer insumos para gerar fitoterápicos, fitofármacos e protótipos de novas drogas com importância econômica. Ela cita dados dos autores Newman & Cragg, do Instituto Nacional de Câncer dos Estados Unidos, referentes a 2016, estimando que aproximadamente 63% de fármacos utilizados para o tratamento de câncer eram derivados diretamente ou indiretamente de produtos naturais. “Mas é importante salientar que a planta produz substâncias para as suas necessidades. Portanto, é preciso cuidado quando queremos tirar proveito dela.”
Medicamento
A tese de Vanessa Helena gerou dados que possibilitam estabelecer as doses corretas em futuros estudos clínicos visando ao desenvolvimento e registro de um medicamento fitoterápico originado da sucupira. Mary Ann Foglio considera que o projeto alcançou a fase de avaliação de riscos no uso dos frutos, viabilizando uma solicitação para testes em humanos e alimentando ótimas perspectivas para a produção de um medicamento. “Os dados e métodos consistentes obtidos pelo grupo dão suporte à intensificação dos estudos pré-clínicos para viabilizar um medicamento fitoterápico (ou alopático) produzido com extratos e frações enriquecidas por compostos ativos da espécie Pterodon pubescens.”
A professora explica que o estudo de determinada planta é um processo longo e com várias etapas. Neste projeto da sucupira, ao longo dos anos, a equipe de pesquisadores caracterizou os compostos dos frutos e comprovou sua funcionalidade como analgésico e anti-inflamatório, e também analisou os efeitos da “garrafada”. “A Pterodon pubescens possui é constituída principalmente de vouacapanos e compostos atípicos. Verificamos que no chá se extrai apenas um tipo de composto, os vouacapanos, que estão envolvidos com o alívio da dor, mas apresentam uma potência bem inferior.”
Conforme a orientadora da tese, com o extrato, que reúne os dois grupos de compostos, a potência aumenta e, consequentemente, a quantidade necessária de frutos é bem menor. “Trata-se de um efeito sinérgico bem interessante, já que expomos o indivíduo a uma concentração bem menor da substância. A palavra sinergia é derivada da palavra grega synergo´z, que significa ‘trabalhando juntos’. A busca de sinergia no campo da farmacologia refere-se à elucidação e quantificação da ação de medicamentos administrados em combinação. A literatura científica vem demonstrando com frequência que a ação farmacológica do princípio ativo isolado difere da ação dos extratos brutos e fitoterápicos. Acredita-se que essas vantagens terapêuticas encontradas em medicamentos fitoterápicos decorrem de interações sinérgicas que potencializam os seus efeitos farmacológicos.”
Na opinião de Mary Ann Foglio, os resultados alcançados por seu grupo trazem impactos significativos sob diferentes aspectos, contribuindo com a literatura por meio de publicação dos resultados, depósito de patentes e desenvolvimento de produto fitoterápico oriundo de fontes ecologicamente sustentáveis. “Os frutos são produtos renováveis que permitirão uma produção contínua dos insumos, formação de recursos humanos, obtenção de fármacos para dores crônicas e geração de emprego nos setores agrícola e farmacêutico.”
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Topical curcumin gel effective in treating burns and scalds
Date: March 14, 2017
Source: Pensoft Publishers
Summary:
What is the effect of Topical Curcumin Gel for treating burns and scalds? In a recent research paper, investigators stress that use of topical curcumin gel for treating skin problems, like burns and scalds, is very different and appears to work more effectively, when compared to taking curcumin tablets by mouth for other conditions.
These are results from 5 days upon application of curcumin gel to burns, and results after 6 weeks.
Credit: Dr. Madalene Heng
What is the effect of Topical Curcumin Gel for treating burns and scalds? In a recent research paper, published in the open access journal BioDiscovery, Dr. Madalene Heng, Clinical Professor of Dermatology at the David Geffen School of Medicine, stresses that use of topical curcumin gel for treating skin problems, like burns and scalds, is very different, and appears to work more effectively, when compared to taking curcumin tablets by mouth for other conditions.
"Curcumin gel appears to work much better when used on the skin because the gel preparation allows curcumin to penetrate the skin, inhibit phosphorylase kinase and reduce inflammation," explains Dr Heng.
In this report, use of curcumin after burns and scalds were found to reduce the severity of the injury, lessen pain and inflammation, and improve healing with less than expected scarring, or even no scarring, of the affected skin. Dr. Heng reports her experience using curcumin gel on such injuries using three examples of patients treated after burns and scalds, and provides a detailed explanation why topical curcumin may work on such injuries.
Curcumin is an ingredient found in the common spice turmeric. Turmeric has been used as a spice for centuries in many Eastern countries and gives well known dishes, such as curry, their typical yellow-gold color. The spice has also been used for cosmetic and medical purposes for just as long in these countries.
In recent years, the medicinal value of curcumin has been the subject of intense scientific studies, with publication numbering in the thousands, looking into the possible beneficial effects of this natural product on many kinds of affliction in humans.
This study published reports that topical curcumin gel applied soon after mild to moderate burns and scalds appears to be remarkably effective in relieving symptoms and improved healing of the affected skin.
"When taken by mouth, curcumin is very poorly absorbed into the body, and may not work as well," notes Dr. Heng. "Nonetheless, our tests have shown that when the substance is used in a topical gel, the effect is notable."
The author of the study believes that the effectiveness of curcumin gel on the skin -- or topical curcumin -- is related to its potent anti-inflammatory activity. Based on studies that she has done both in the laboratory and in patients over 25 years, the key to curcumin's effectiveness on burns and scalds is that it is a natural inhibitor of an enzyme called phosphorylase kinase.
This enzyme in humans has many important functions, including its involvement in wound healing. Wound healing is the vital process that enables healing of tissues after injury. The process goes through a sequence of acute and chronic inflammatory events, during which there is redness, swelling, pain and then healing, often with scarring in the case of burns and scalds of the skin. The sequence is started by the release of phosphorylase kinase about 5 mins after injury, which activates over 200 genes that are involved in wound healing.
Dr. Heng uses curcumin gel for burns, scalds and other skin conditions as complementary treatment, in addition to standard treatment usually recommended for such conditions.
Story Source:
Materials provided by Pensoft Publishers. The original story is licensed under a Creative Commons License. Note: Content may be edited for style and length.
Journal Reference:
Madalene Heng. Phosphorylase Kinase Inhibition Therapy in Burns and Scalds. BioDiscovery, 2017; 20: e11207 DOI: 10.3897/biodiscovery.20.e11207
Cite This Page:
Pensoft Publishers. "Topical curcumin gel effective in treating burns and scalds." ScienceDaily. ScienceDaily, 14 March 2017. <www.sciencedaily.com/releases/2017/03/170314135411.htm>.
Cannabinoids remove plaque-forming Alzheimer's proteins from brain cells
Date: June 29, 2016
Source: Salk Institute
Summary:
Scientists have found preliminary evidence that tetrahydrocannabinol (THC) and other compounds found in marijuana can promote the cellular removal of amyloid beta, a toxic protein associated with Alzheimer's disease.
Preliminary lab studies by Salk Professor David Schubert suggest that the molecule THC reduces beta amyloid proteins in human neurons.
Credit: Salk Institute
Salk Institute scientists have found preliminary evidence that tetrahydrocannabinol (THC) and other compounds found in marijuana can promote the cellular removal of amyloid beta, a toxic protein associated with Alzheimer's disease.
While these exploratory studies were conducted in neurons grown in the laboratory, they may offer insight into the role of inflammation in Alzheimer's disease and could provide clues to developing novel therapeutics for the disorder.
"Although other studies have offered evidence that cannabinoids might be neuroprotective against the symptoms of Alzheimer's, we believe our study is the first to demonstrate that cannabinoids affect both inflammation and amyloid beta accumulation in nerve cells," says Salk Professor David Schubert, the senior author of the paper.
Alzheimer's disease is a progressive brain disorder that leads to memory loss and can seriously impair a person's ability to carry out daily tasks. It affects more than five million Americans according to the National Institutes of Health, and is a leading cause of death. It is also the most common cause of dementia and its incidence is expected to triple during the next 50 years.
It has long been known that amyloid beta accumulates within the nerve cells of the aging brain well before the appearance of Alzheimer's disease symptoms and plaques. Amyloid beta is a major component of the plaque deposits that are a hallmark of the disease. But the precise role of amyloid beta and the plaques it forms in the disease process remains unclear.
In a manuscript published in June 2016's Aging and Mechanisms of Disease, Salk team studied nerve cells altered to produce high levels of amyloid beta to mimic aspects of Alzheimer's disease.
The researchers found that high levels of amyloid beta were associated with cellular inflammation and higher rates of neuron death. They demonstrated that exposing the cells to THC reduced amyloid beta protein levels and eliminated the inflammatory response from the nerve cells caused by the protein, thereby allowing the nerve cells to survive.
"Inflammation within the brain is a major component of the damage associated with Alzheimer's disease, but it has always been assumed that this response was coming from immune-like cells in the brain, not the nerve cells themselves," says Antonio Currais, a postdoctoral researcher in Schubert's laboratory and first author of the paper. "When we were able to identify the molecular basis of the inflammatory response to amyloid beta, it became clear that THC-like compounds that the nerve cells make themselves may be involved in protecting the cells from dying."
Brain cells have switches known as receptors that can be activated by endocannabinoids, a class of lipid molecules made by the body that are used for intercellular signaling in the brain. The psychoactive effects of marijuana are caused by THC, a molecule similar in activity to endocannabinoids that can activate the same receptors. Physical activity results in the production of endocannabinoids and some studies have shown that exercise may slow the progression of Alzheimer's disease.
Schubert emphasized that his team's findings were conducted in exploratory laboratory models, and that the use of THC-like compounds as a therapy would need to be tested in clinical trials.
In separate but related research, his lab found an Alzheimer's drug candidate called J147 that also removes amyloid beta from nerve cells and reduces the inflammatory response in both nerve cells and the brain. It was the study of J147 that led the scientists to discover that endocannabinoids are involved in the removal of amyloid beta and the reduction of inflammation.
Other authors on the paper include Oswald Quehenberger and Aaron Armando at the University of California, San Diego; and Pamela Maher and Daniel Daughtery at the Salk Institute.
The study was supported by the National Institutes of Health, The Burns Foundation and The Bundy Foundation.
Story Source:
Materials provided by Salk Institute. Note: Content may be edited for style and length.
Journal Reference:
Antonio Currais, Oswald Quehenberger, Aaron M Armando, Daniel Daugherty, Pam Maher, David Schubert. Amyloid proteotoxicity initiates an inflammatory response blocked by cannabinoids. npj Aging and Mechanisms of Disease, 2016; 2: 16012 DOI: 10.1038/npjamd.2016.12
Cite This Page:
Salk Institute. "Cannabinoids remove plaque-forming Alzheimer's proteins from brain cells." ScienceDaily. ScienceDaily, 29 June 2016. <www.sciencedaily.com/releases/2016/06/160629095609.htm>.
Cannabidiol reduces seizures in children with severe epilepsy
Date: May 26, 2017
Source: Ann & Robert H. Lurie Children's Hospital of Chicago
Summary:
Children with Dravet syndrome, a severe form of epilepsy, had fewer seizures after taking a daily oral solution of the cannabis compound called cannabidiol, which does not have the psychoactive properties of marijuana, results from a double-blind, placebo-controlled trial reveal.
Results from a double-blind, placebo-controlled trial published in The New England Journal of Medicinerevealed that children with Dravet syndrome, a severe form of epilepsy, had fewer seizures after taking a daily oral solution of the cannabis compound called cannabidiol, which does not have the psychoactive properties of marijuana. Over a 14-week treatment with cannabidiol, convulsive seizures dropped from a monthly average of 12.4 to 5.9. In comparison, seizures in the placebo group decreased from a monthly average of 14.9 to 14.1. During the study, seizures stopped completely in 5 percent of patients taking cannabidiol.
"Seizures in Dravet syndrome are extremely difficult to control and they can be deadly," says study co-author Linda Laux, MD, from Stanley Manne Children's Research Institute at Ann & Robert H. Lurie Children's Hospital of Chicago. "Our results are encouraging, especially considering that we don't have any antiepileptic drugs approved for Dravet syndrome in the U.S."
The study included 120 children and young adults with Dravet syndrome and drug-resistant seizures. They were randomly assigned to receive either cannabidiol or a placebo, in addition to standard antiepileptic treatment.
Adverse events were reported in 93 percent of the patients taking cannabidiol, compared to 75 percent of the patients in the placebo group. The most common side effects were drowsiness, diarrhea and decreased appetite.
"We will need more data to determine the long-term efficacy and safety of cannabidiol for Dravet syndrome," says Laux, who is the Medical Director of the Comprehensive Epilepsy Center at Lurie Children's and Assistant Professor of Pediatrics at Northwestern University Feinberg School of Medicine.
Story Source:
Materials provided by Ann & Robert H. Lurie Children's Hospital of Chicago. Note: Content may be edited for style and length.
Journal Reference:
Orrin Devinsky, J. Helen Cross, Linda Laux, Eric Marsh, Ian Miller, Rima Nabbout, Ingrid E. Scheffer, Elizabeth A. Thiele, Stephen Wright. Trial of Cannabidiol for Drug-Resistant Seizures in the Dravet Syndrome. New England Journal of Medicine, 2017; 376 (21): 2011 DOI: 10.1056/NEJMoa1611618
Cite This Page:
Ann & Robert H. Lurie Children's Hospital of Chicago. "Cannabidiol reduces seizures in children with severe epilepsy." ScienceDaily. ScienceDaily, 26 May 2017. <www.sciencedaily.com/releases/2017/05/170526085003.htm>.
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