Link Clarified Between Gut Microbes and Emotions
A 2017 article in the journal Microbiome suggests that gene-regulating molecules called microRNAs in the brain may be the link between microbes in the gut and emotions.
The research by Alan E. Hoban and colleagues looked at mice raised in a sterile, microbe-free environment. These mice had fewer anxiety-like behaviors than mice raised among the usual bacteria, viruses, and fungi. This finding implies that the microbiome—the trillions of microbes that live in and around our bodies—affects brain functions. In this case, the affected regions were the prefrontal cortex and the amygdala, which both play a role in the detection and response to fearful stimuli. These regions showed alterations in the level of microRNAs present.
When Hoban and colleagues introduced microbes into the animal’s systems, some microRNAs did not bounce back, suggesting that there may be a crucial window early in life when the presence of microbes is needed for the brain to develop normally.
In general, this research shows that microRNAs are key to understanding the link between the microbiome and the brain.
Music, Mindfulness and Exercise Improve Brain Functioning
Psychiatrists should take the lead in endorsing general wellness and encouraging healthy behaviors, says researcher James Hudziak. He suggests that opportunities to practice music, mindfulness, and exercise should be made available to all school children to increase brain health, and that more intensive efforts are necessary for children in families that are at risk for mood and behavioral difficulties or in children who show some dysfunction in these areas. Hudziak has implemented a statewide program in Vermont that encourages families to engage in these healthy practices.
Hudziak and colleagues analyzed brain scans of 232 children ages 6 to 18, looking for relationships between cortical thickness and musical training. They found that practicing an instrument such as the piano or violin increased working memory, gray matter volume in the brain, and the ability to screen out irrelevant noise. Practicing mindfulness increased white matter volume and reduced anxiety and depression. Exercise also increased brain volume and neuropsychological abilities.
Now Hudziak urges parents to advocate for the teaching of music, mindfulness, and exercise in schools as a way of improving general health, especially since music and gym are often the first programs to be cut when schools face budget shortages. Hudziak suggests that opportunities for athletics should be provided to all children, independent of their skill level, rather than only for the best athletes who “make the team.” Intramural teams should be open to all children, including those with less ability or minimal athletic skills. Exercise, teamwork, and friendships benefit all children.
For more information about the programs Hudziak implemented in Vermont, use the internet to search for the Vermont Family Based Approach, see his book Developmental Psychopathology and Wellness: Genetic and Environmental Influences, or call the University of Vermont Medical Center at (802)847-0000 or (800)358-1144.
Another tool that may be useful to parents of children aged 2 to 12 who are at risk for mood disorders is our Child Network, a secure online portal where parents can complete quick weekly ratings of their child’s mood and behavior, which is then graphed over time and can be used to show the child’s doctors how his or her symptoms are fluctuating and how well any treatment is working.
Vitamin D Important for Brain Function, and Often Deficient
Vitamin D plays an important role in many brain functions, including synapse creation, calcium signaling, reduction of free radicals, neurotransmitter production, immune regulation, and brain development. Deficiencies in vitamin D have been linked to depression and schizophrenia. Some research has suggested that vitamin D supplementation can improve depressive symptoms, but there is still debate about a possible role for vitamin D in treating bipolar disorder.
At the 2014 meeting of the International Society for Bipolar Disorders, researcher Baseok Cha discussed the importance of vitamin D supplementation in bipolar patients, who often have deficient or insufficient levels. People receive 50 to 90% of their vitamin D from sunlight, and the rest from diet and supplements. Too much sunscreen can be a problem if it prevents a person from receiving enough vitamin D from sunlight.
The type of vitamin in supplements, D3, is converted to 25 hydroxy vitamin D in the liver, and then to 1,25 hydroxy vitamin D in the kidney. Levels of 25 hydroxy vitamin D below 20 indicate deficiency while levels between 20 and 29 indicate insufficiency. Low levels of 25 hydroxy vitamin D3 in newborns is a risk factor for schizophrenia, and vitamin D supplementation reduces this risk. Fish oils increase vitamin D, and it is possible that some of the therapeutic effects of omega-3 fatty acids in depression relate to vitamin D.
Two out of four recent studies of vitamin D supplementation have been positive, the last by Khoraminya et al. in the Australia and New Zealand Journal of Psychiatry in 2013, in which daily doses of 1,500 IU were used. Cha et al. found significantly lower levels of 25 hydroxy vitamin D in a Korean study of 21 patients with schizophrenia, 86 patients with bipolar disorder, and 42 patients with depression (mean levels about 15 µg/ml) compared to 31 controls (mean levels about 20 µg/ml).
