The brain-gut axis is of increasing interest to researchers. The mechanism of how stress leads to intestinal distress is being unraveled, and there is now definitive proof that probiotics influence the brain activity of humans.
Finding ways to improve the health of our children is a constant goal for parents and is also a driving factor for medical research. The use of probiotic bacteria to improve children’s health has not been ignored, and researchers are eagerly examining the possible benefits. In Sweden, healthy infants were fed cereal with and without Lactobacillus paracasei ssp. paracasei F19 to see if the bacteria would have beneficial effects on blood lipid parameters associated with obesity. After treatment, the infants displayed significant changes in their blood lipids associated with lowered visceral fat and a healthier gut barrier. Whether these changes actually will lead to improved health still remains to be seen, however.
In Indonesia, researchers also explored the effects of two different probiotics (Lactobacillus casei CRL 431 and Lactobacillus reuteri DSM 17938) on children. Their goal was to see if the probiotics could positively affect the children’s growth. The bacteria were given to the children with a milk ration. After 6 months of supplementation, the researchers found improvements associated with both probiotics, but these improvements were not the same. L. reuteri DSM 17938 appeared to be more beneficial leading to increases in overall weight and speed of growth.
Probiotics and HIV
The Human Immunodeficiency Virus, which causes AIDS, infects primarily T cells leading to a reduction of these cells and a loss of immune response. The virus specifically targets these cells by using a surface marker, called CD4, to enter the cells. Lactobacilli are known to counteract this loss of T cells, but it wasn’t known how. Researchers in China are now one step closer to knowing how this works. It appears that Lactobacilli express a protein that looks a lot like CD4. In this way, the bacteria are able to bind to the virus and reduce the chances that they attach to CD4 expressing T cells.
Beneficial Bacteria and the Brain
It is generally accepted that stress is unhealthy, and most of us know that too much stress can lead to intestinal problems. Still, the details of how stress translates to gut issues aren’t well known. Using mice, researchers from China and the United States, have made progress. The mice were stressed in a way that leads to a form of irritable bowel syndrome (IBS). Using a host of molecular techniques, the researchers discovered that a hormone, called corticotropin-releasing hormone, was released and that this had negative effects on the immune response. The loss of immune responses appeared to affect the composition of the microflora in the intestines leading to the IBS. Therapy designed to prevent the changes in the intestinal flora using probiotics was successful in preventing the IBS-like symptoms.
Another pivotal study this week performed by brain scientists from the US delved into the ability of fermented milk containing Bifidobacterium animalis subsp Lactis, Streptococcus thermophiles, Lactobacillus bulgaricus, and Lactococcus lactis subsp Lactis to change the brain activity. Using functional magnetic resonance imaging they looked at the brain responses of women stimulated by emotional stimuli. They found that the fermented milk reduced them. This result suggests that probiotics may be useful for treating stress and pain associated with intestinal and/or emotional distress.
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- Sun Y, Zhang M, Chen CC, Gillilland M 3rd, Sun X, El-Zaatari M, Huffnagle GB, Young VB, Zhang J, Hong SC, Chang YM, Gumucio DL, Owyang C, Kao JY. Stress-Induced Corticotropin-Releasing Hormone-Mediated NLRP6 Inflammasome Inhibition and Transmissible Enteritis in Mice. Gastroenterology. 2013 Jun;144(7):1478-1487.e8.
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