Causal link found between vitamin D, serotonin synthesis and autism in new study

Date: February 26, 2014
Source: Children's Hospital & Research Center Oakland
 

Summary:
Serotonin and vitamin D have been proposed to play a role in autism, however, no causal mechanism has been established. Now, researchers show that serotonin, oxytocin, and vasopressin, three brain hormones that affect social behavior related to autism, are all activated by vitamin D hormone. Supplementation with vitamin D and tryptophan would be a practical and affordable solution to help prevent autism and possibly ameliorate some symptoms of the disorder.
 
This study suggests dietary intervention with vitamin D, tryptophan and omega-3 fatty acids would boost brain serotonin concentrations and help prevent and possibly ameliorate some of the symptoms associated with ASD without side effects.
Credit: © Bob Rannells / Fotolia

A new study by Rhonda Patrick, PhD and Bruce Ames, PhD of Children's Hospital Oakland Research Institute (CHORI) demonstrates the impact that Vitamin D may have on social behavior associated with Autism Spectrum Disorder (ASD). Dr. Patrick and Dr. Ames show that serotonin, oxytocin, and vasopressin, three brain hormones that affect social behavior, are all activated by vitamin D hormone. Autism, which is characterized by abnormal social behavior, has previously been linked to low levels of serotonin in the brain and to low vitamin D levels, but no mechanism has linked the two until now.

In this study, Dr. Patrick and Dr. Ames show that vitamin D hormone activates the gene that makes the enzyme tryptophan hydroxylase 2 (TPH2), that converts the essential amino acid tryptophan, to serotonin in the brain. This suggests that adequate levels of vitamin D may be required to produce serotonin in the brain where it shapes the structure and wiring of the brain, acts as a neurotransmitter, and affects social behavior. They also found evidence that the gene that makes the enzyme tryptophan hydroxylase 1 (TPH1) is inhibited by vitamin D hormone, which subsequently halts the production of serotonin in the gut and other tissues, where when found in excess it promotes inflammation.

This mechanism explains many of the known, but previously not understood, facts about autism including: 1) the "serotonin anomaly" low levels of serotonin in the brain and high levels in the blood of autistic children; 2) the preponderance of male over female autistic children: estrogen, a similar steroid hormone, can also boost the brain levels of serotonin in girls; 3) the presence of autoimmune antibodies to the fetal brain in the mothers of autistic children: vitamin D regulates the production of regulatory T-cells via repression of TPH1. The Patrick/Ames mechanism is relevant to the prevention of autism, and likely its treatment.

The current guidelines for adequate vitamin D levels are concentrations above 30 ng/ml. Most Americans' vitamin D is made in the skin from exposure to UVB radiation; however, melanin pigment and sunscreen inhibit this action. This is an important cause of the well-known widespread vitamin D deficiency among dark-pigmented Americans, particularly those living in Northern latitudes. The most recent National Health and Examination survey reports that greater than 70% of U.S. population does not meet this requirement and that adequate vitamin D levels have plummeted over the last couple of decades. This precipitous drop in adequate levels of vitamin D in the US is concurrent with the rise in autism rates.

The study suggests dietary intervention with vitamin D, tryptophan and omega 3 fatty acids would boost brain serotonin concentrations and help prevent and possibly ameliorate some of the symptoms associated with ASD without side effects. There is little vitamin D present in food and fortification is still inadequate as is the amount in most multivitamin and prenatal supplements. Vitamin D supplements are inexpensive and offer a simple solution to raise vitamin D levels to an adequate status. In addition, vitamin D levels should be routinely measured in everyone and should become a standard procedure in prenatal care.

Story Source:

The above story is based on materials provided by Children's Hospital & Research Center Oakland. Note: Materials may be edited for content and length.

Journal Reference:
R. P. Patrick, B. N. Ames. Vitamin D hormone regulates serotonin synthesis. Part 1: relevance for autism. The FASEB Journal, 2014; DOI: 10.1096/fj.13-246546

Cite This Page:

Children's Hospital & Research Center Oakland. "Causal link found between vitamin D, serotonin synthesis and autism in new study." ScienceDaily. ScienceDaily, 26 February 2014. <www.sciencedaily.com/releases/2014/02/140226110836.htm>.
 

Link:
http://www.sciencedaily.com/releases/2014/02/140226110836.htm  

Why breastfed babies are so smart: Moms who breastfeed are often responsive and read to their babies

Date:February 26, 2014
Source: Brigham Young University

Summary:
Research has shown that children who were breastfed score higher on IQ tests and perform better in school, but the reason why remained unclear. Now a new study shows that two parenting skills deserve the credit. Responsiveness to children's emotional cues boosts kids' math and reading skills. Reading to children as early as 9 months of age also significantly improves school readiness. These two skills can give kids an extra 2-3 months' worth of brain development.
 

Two parenting skills form the real source of cognitive boost in breastfed babies: Responding to children's emotional cues and reading to children starting at 9 months of age. Breastfeeding mothers tend to do both of these things. Credit: Image courtesy of Brigham Young University

Loads of studies over the years have shown that children who were breastfed score higher on IQ tests and perform better in school, but the reason why remained unclear.

Is it the mother-baby bonding time, something in the milk itself or some unseen attribute of mothers who breastfeed their babies?

Now a new study by sociologists at Brigham Young University pinpoints two parenting skills as the real source of this cognitive boost: Responding to children's emotional cues and reading to children starting at 9 months of age. Breastfeeding mothers tend to do both of those things, said lead study author Ben Gibbs.

"It's really the parenting that makes the difference," said Gibbs. "Breastfeeding matters in others ways, but this actually gives us a better mechanism and can shape our confidence about interventions that promote school readiness."

Gibbs authored the study with fellow BYU professor Renata Forste for the March issue of The Journal of Pediatrics. According to their analysis, improvements in sensitivity to emotional cues and time reading to children could yield 2-3 months' worth of brain development by age 4 (as measured by math and reading readiness assessments).

"Because these are four-year-olds, a month or two represents a non-trivial chunk of time," Gibbs said. "And if a child is on the edge of needing special education, even a small boost across some eligibility line could shape a child's educational trajectory."

The BYU scholars utilized a national data set that followed 7,500 mothers and their children from birth to five years of age. The data set is rich with information on the home environment, including how early and how often parents read to their kids. Additionally, each of the mothers in the study also participated in video-taped activities with their children. As the child tried to complete a challenging task, the mother's supportiveness and sensitivity to their child's emotional cues were measured.

The study gained editorial praise from child development expert Sandra Jacobson of Wayne State University School of Medicine. She noted that children in the study who were breastfed for 6 months or longer performed the best on reading assessments because they also "experienced the most optimal parenting practices.

"Gibbs and Forste found that reading to an infant every day as early as age 9 months and sensitivity to the child's cues during social interactions, rather than breastfeeding per se, were significant predictors of reading readiness at age 4 years," wrote Jacobson.

The BYU researchers note that the most at-risk children are also the least likely to receive the optimal parenting in early childhood. Single moms in the labor force, for example, don't have the same luxuries when it comes to breastfeeding and quality time with the children. Parents with less education don't necessarily hear about research-based parenting practices, either.

"This is the luxury of the advantaged," Forste said. "It makes it harder to think about how we promote environments for disadvantaged homes. These things can be learned and they really matter. And being sensitive to kids and reading to kids doesn't have to be done just by the mother."

Story Source:

The above story is based on materials provided by Brigham Young University. Note: Materials may be edited for content and length.

Journal Reference:
Benjamin G. Gibbs, Renata Forste. Breastfeeding, Parenting, and Early Cognitive Development. The Journal of Pediatrics, 2014; 164 (3): 487 DOI: 10.1016/j.jpeds.2013.10.015

Cite This Page:

Brigham Young University. "Why breastfed babies are so smart: Moms who breastfeed are often responsive and read to their babies." ScienceDaily. ScienceDaily, 26 February 2014. <www.sciencedaily.com/releases/2014/02/140226155645.htm>.

Link:
http://www.sciencedaily.com/releases/2014/02/140226155645.htm