HKBU discovers new treatment for diarrhea-predominant irritable bowel syndrome targeting low-protein foods can reduce symptoms

About 7% of adults in Hong Kong suffer from IBS. Symptoms include irregular bowel movements, abdominal discomfort, bloating or diarrhea.

A study by the School of Chinese Medicine of Baptist University found for the first time that the human intestinal bacterium Ruminococcus vivata is the main trigger factor of diarrhea-predominant irritable bowel syndrome, and the phenylethylamine, tryptamine or TAAR1 pathway can act as a trigger for diarrhea-predominant irritable bowel syndrome. New therapeutic targets for irritable bowel syndrome.

Studies have also found that eating low-protein foods such as fresh fruits, vegetables, and bread may help reduce intestinal peristalsis in diarrhea-predominant irritable bowel syndrome.

The research results have been published in the internationally renowned scientific journal "Cell Host & Microbe".

Professor Bian Zhaoxiang, Director of the Clinical Department of the School of Chinese Medicine and Tsang Shiu Tim Clinical Research Professor of Chinese Medicine (middle), Dr. Wang Kailiang, Assistant Professor of the Department of Teaching and Research (right), and postdoctoral researcher Dr. Lixiang Zhai (left), have discovered the human intestinal tract for the first time. The gut bacterium Ruminococcus mobilis is a major trigger of diarrhea-predominant IBS.

(Provided by HKBU)

Diarrhea-predominant IBS is the most common form of the condition. There is no cure and most clinical treatments focus on symptom relief.

The research team led by Bian Zhaoxiang, Director of the Clinical Department of the School of Chinese Medicine and Tsang Shiu Tim Clinical Research Professor of Chinese Medicine, Wang Kailiang, Assistant Professor of the Department of Teaching and Research, and Zhai Lixiang, a postdoctoral researcher, took stool samples from 290 patients earlier to implement the study. Thousands of food components and their decomposition products were found to contain a large amount of phenylethylamine and tryptamine in their feces. related to the severity of diarrhea symptoms.

Phenylethylamine and tryptamine are mainly produced by "Ruminococcus gnavus". The research team found a large number of this bacteria in the stool samples, and transplanted the bacteria into the intestines of mice, and found that the mice developed diarrhea Diarrhea symptoms of irritable bowel syndrome type.

In addition, mice fed directly with phenylethylamine or tryptamine had increased stool frequency and colonic secretions.

The results demonstrate that phenylethylamine and tryptamine produced by Ruminococcus mobilis can induce diarrhea-predominant IBS in mammals without other risk factors.

Experiments also found that phenylethylamine and tryptamine directly stimulate the "chromaffin cells" in the intestine to produce serotonin by activating the "trace amine-associated receptor" (TAAR1), which in turn induces intestinal peristalsis and secretion disorders. Symptoms of Irritable Syndrome.

The research team experimented with mice transplanted with stool samples of diarrhea-predominant irritable bowel syndrome and found that using specific inhibitors to prevent the activation of TAAR1 can effectively reduce diarrhea symptoms, that is, the phenylethylamine, tryptamine or TAAR1 pathway, is New therapeutic targets for diarrhea-predominant irritable bowel syndrome.

In addition, the research team also found that a diet low in "phenylalanine" content can reduce the production of phenylethylamine and tryptamine by microorganisms, thereby inhibiting intestinal peristalsis in mice.

Dietary phenylalanine is an amino acid that is digested and broken down into phenylethylamine.

Foods with low protein content, such as fresh fruits, vegetables, bread, etc., have relatively low phenylalanine content.

Wang Kailiang said that developing strategies to reduce the conversion of dietary amino acids into phenylethylamine and tryptamine by microorganisms, such as controlling diet to reduce the intake of high-protein foods with high phenylalanine content, or controlling the risk of diarrhea-predominant irritable bowel syndrome feasible method.

City University’s storm drain drainage contains plasticizers research reveals the highest concentration of Streptococcus beta in Kwai Chung may threaten the health of residents｜Government study: 20% of pregnant women in Hong Kong are screened for bacteria and successfully reduce infant infection How many cups do you drink a day to reduce the risk of diabetes and urine by 17%?

Epidemic｜British study shows anti-epidemic oral drug Monapiravir can speed up recovery