Serotonin or called 5-hydroxytryptamine (5-HT), is a chemical found in the human body. It is mainly found in the brain, bowels and blood platelets. It's a neurotransmitter that is synthesized, stored, and released by specific neurons in the brain. Serotonin regulates many important processes, such as mood, sleep, appetite and memory. Abnormalities in the levels of serotonin are associated with a variety of diseases, including anxiety, panic attacks, obesity, insomnia, and fibromyalgia. According to a study published online 31 May 2016 in the journal Nature, researchers have found that a protein called TLR2, which helps detect gut microbes, also modulates the level of a neurotransmitter, serotonin. The study, led by Prof José E. Mesonero at Universidad de Zaragoza, may lead to a better understanding of how gut microbes can affect our physiology. TLR2 is a member of the Toll-like receptor (TLR) family, which plays a critical role in pathogen recognition and activation of innate immunity. Previous studies have demonstrated that TLR2 helps maintain intestinal homeostasis and improves inflammatory intestinal injury. Another molecule called serotonin regulates peristaltic and secretory reflexes in the gut. Evidence shows that serotonin is also involved in intestinal inflammation. Mesonero's team set out the investigate the effect of TLR2 on intestinal serotonin transporter (SERT). Using cultured cells, they discovered that TLR2 activation inhibits SERT activity by decreasing the level of SERT protein. This discovery was confirmed by experiments in mice. In mice that lacked TLR2, the researchers observed an increase in intestinal SERT expression. "The protein TLR2 alters the availability of serotonin," said study first author, Dr Eva Latorre. SERT is an important target for a variety of diseases. There is a view that gut microbes can interfere with SERT and thus control serotonin level. Intestinal epithelial cells express TLRs, which help to discriminate between beneficial and harmful microbes in the gut. In another word, TLR activation plays a role in maintaining gut health. Moreover, if TLR function is impaired, inflammatory bowel disease may occur. TLR2 is activated by molecules produced by microbes. This study may help to understand how gut microbes affect our physiology and the pathogenesis of inflammatory bowel disease and other diseases, which would facilitate the development of new treatments. Cusabio offers TLR2, SERT and FITC conjugated antibody.
