An overview of traditional Chinese medicine affecting gut microbiota in obesity.

Obesity, a chronic metabolic disease with a complex pathophysiology, is caused by several variables. High-fat diets lead to the disruption of the gut microbiota and impaired gut barrier function in obese people. The dysbiosis and its metabolites through the intestinal barrier lead to an imbalance in energy metabolism and inflammatory response, which eventually contributes to the development of chronic diseases such as diabetes, hypertension, and cardiovascular disease. Current medicines are therapeutic to obesity in the short term; however, they may bring significant physical and emotional problems to patients as major side effects. Therefore, it is urgent to explore new therapeutic methods that have definite efficacy, can be taken for a long time, and have mild adverse effects. Numerous studies have demonstrated that traditional Chinese medicine (TCM) can control the gut microbiota in a multi-targeted and comprehensive manner, thereby restoring flora homeostasis, repairing damaged intestinal mucosal barriers, and eventually curbing the development of obesity. The active ingredients and compounds of TCM can restore the normal physiological function of the intestinal mucosal barrier by regulating gut microbiota to regulate energy metabolism, inhibit fat accumulation, affect food appetite, and reduce intestinal mucosal inflammatory response, thereby effectively promoting weight loss and providing new strategies for obesity prevention and treatment. Although there are some studies on the regulation of gut microbiota by TCM to prevent and treat obesity, all of them have the disadvantage of being systematic and comprehensive. Therefore, this work comprehensively describes the molecular mechanism of obesity mediated by gut microbiota based on the research state of obesity, gut microbiota, and TCM. A comprehensive and systematic summary of TCM targeting the regulation of gut microbiota for the treatment of obesity should be conducted in order to provide new strategies and ideas for the treatment of obesity.

Li D ，Tang W ，Wang Y ，Gao Q ，Zhang H ，Zhang Y ，Wang Y ，Yang Y ，Zhou Y ，Zhang Y ，Li H ，Li S ，Zhao H ... -  《Frontiers in Endocrinology》

Repairing gut barrier by traditional Chinese medicine: roles of gut microbiota.

Gut barrier is not only part of the digestive organ but also an important immunological organ for the hosts. The disruption of gut barrier can lead to various diseases such as obesity and colitis. In recent years, traditional Chinese medicine (TCM) has gained much attention for its rich clinical experiences enriched in thousands of years. After orally taken, TCM can interplay with gut microbiota. On one hand, TCM can modulate the composition and function of gut microbiota. On the other hand, gut microbiota can transform TCM compounds. The gut microbiota metabolites produced during the actions of these interplays exert noticeable pharmacological effects on the host especially gut barrier. Recently, a large number of studies have investigated the repairing and fortifying effects of TCM on gut barriers from the perspective of gut microbiota and its metabolites. However, no review has summarized the mechanism behand this beneficiary effects of TCM. In this review, we first briefly introduce the unique structure and specific function of gut barrier. Then, we summarize the interactions and relationship amidst gut microbiota, gut microbiota metabolites and TCM. Further, we summarize the regulative effects and mechanisms of TCM on gut barrier including physical barrier, chemical barrier, immunological barrier, and microbial barrier. At last, we discuss the effects of TCM on diseases that are associated gut barrier destruction such as ulcerative colitis and type 2 diabetes. Our review can provide insights into TCM, gut barrier and gut microbiota.

Zhou Y ，Zhang D ，Cheng H ，Wu J ，Liu J ，Feng W ，Peng C ... -  《-》

Crosstalk between traditional Chinese medicine-derived polysaccharides and the gut microbiota: A new perspective to understand traditional Chinese medicine.

Polysaccharide is a kind of macromolecule polymer composed of monosaccharides connected by glycosidic bonds. Traditional Chinese medicine (TCM), composed of various bioactive ingredients, is usually rich in polysaccharides. In recent years, extensive research on TCM polysaccharides has demonstrated their pharmacological effects. Polysaccharides can hardly be catabolized by enzymes encoded by the human genome but can be degraded to absorbable metabolites by bacteria inhabiting the colon. Hence, the gut microbiota plays a vital role in degrading TCM polysaccharides into short-chain fatty acids (SCFAs) which exert physiological functions locally and systemically. Besides, TCM polysaccharides can also modulate the composition and activities of the gut microbiota by promoting the growth of beneficial bacteria and inhibiting the colonization of pathogenic bacteria, ultimately restoring gut homeostasis and improving human health. In this review, we discuss the extraction and pharmacological effects of TCM polysaccharides, various functions of the gut microbiota, and the interactions between TCM polysaccharides and the gut microbiota, illuminating the mechanisms of TCM polysaccharides modulating host physiology via the gut microbiota. To firmly establish the clinical efficacy of TCM polysaccharides, further high-quality studies especially clinical trials are needed. Generally, discussion on the interplay between TCM polysaccharides and the gut microbiota is expected to elucidate their application prospects and inspire new thoughts in the development of TCM.

Yue B ，Zong G ，Tao R ，Wei Z ，Lu Y ... -  《-》

Gut microbiota: A new target for traditional Chinese medicine in the treatment of depression.

The causes of depression are complex. Many factors are involved in its pathogenesis, including the individual's biological and social environment. Although numerous studies have reported that the gut microbiota plays a significant role in depression, drugs that regulate the gut microbiota to treat depression have not yet been comprehensively reviewed. At the same time, more and more attention has been paid to the characteristics of traditional Chinese medicine (TCM) in improving depression by regulating gut microbiota. In ancient times, fecal microbiota transplantation was recorded in TCM for the treatment of severe diseases. There are also records in Chinese ancient books about the use of TCM to adjust gut microbiota to treat diseases, which has opened up a unique research field in TCM. Therefore, this article focuses on the pharmacological effects, targets, and mechanisms of TCM in improving depression by mediating the influence of gut microbiota. To summarize the role the gut microbiota plays in depression, highlight potential regulatory targets, and elucidate the anti-depression mechanisms of TCMs through regulation of the gut microbiota. A systematic review of 256 clinical trials and pharmaceutical studies published until June 2022 was conducted in eight electronic databases (Web of Science, PubMed, SciFinder, Research Gate, ScienceDirect, Google Scholar, Scopus, and China Knowledge Infrastructure), according to the implemented PRISMA criteria, using the search terms "traditional Chinese medicine," "depression," and "gut microbiota." Numerous studies reported the effects of different gut bacteria on depression and that antidepressants work through the gut microbiota. TCM preparations based on compound Chinese medicine, the Chinese Materia Medica, and major bioactive components exerted antidepressant-like effects by improving levels of neurotransmitters, short-chain fatty acids, brain-derived neurotrophic factor, kynurenine, and cytokines via regulation of the gut microbiota. This review summarized the anti-depression effects of TCM on the gut microbiota, providing evidence that TCMs are safe and effective in the treatment of depression and may provide a new therapeutic approach.

Li B ，Xu M ，Wang Y ，Feng L ，Xing H ，Zhang K ... -  《-》

Intestinal Escherichia coli and related dysfunction as potential targets of Traditional Chinese Medicine for respiratory infectious diseases.

Traditional Chinese medicine (TCM) has saved countless lives and maintained human health over its long history, especially in respiratory infectious diseases. The relationship between the intestinal flora and the respiratory system has been a popular research topic in recent years. According to the theory of the "gut-lung axis" in modern medicine and the idea that "the lung stands in an interior-exterior relationship with the large intestine" in TCM, gut microbiota dysbiosis is a contributing factor to respiratory infectious diseases, and there is potential means for manipulation of the gut microbiota in the treatment of lung diseases. Emerging studies have indicated intestinal Escherichia coli (E. coli) overgrowth in multiple respiratory infectious diseases, which could exacerbate respiratory infectious diseases by disrupting immune homeostasis, the gut barrier and metabolic balance. TCM is an effective microecological regulator, that can regulate the intestinal flora including E. coli, and restore the balance of the immune system, gut barrier, and metabolism. This review discusses the changes and effects of intestinal E. coli in respiratory infection, as well as the role of TCM in the intestinal flora, E. coli and related immunity, the gut barrier and the metabolism, thereby suggesting the possibility of TCM therapy regulating intestinal E. coli and related immunity, the gut barrier and the metabolism to alleviate respiratory infectious diseases. We aimed to make a modest contribution to the research and development of new therapies for intestinal flora in respiratory infectious diseases and the full utilization of TCM resources. Relevant information about the therapeutic potential of TCM to regulate intestinal E. coli against diseases was collected from PubMed, China National Knowledge Infrastructure (CNKI), and so on. The Plants of the World Online (https://wcsp.science.kew.org) and the Plant List (www.theplantlist.org) databases were used to provide the scientific names and species of plants. Intestinal E. coli is a very important bacterium in respiratory infectious diseases that affects the respiratory system through immunity, the gut barrier and the metabolism. Many TCMs can inhibit the abundance of E. coli and regulate related immunity, the gut barrier and the metabolism to promote lung health. TCM targeting intestinal E. coli and related immune, gut barrier, and metabolic dysfunction could be a potential therapy to promote the treatment and prognosis of respiratory infectious diseases.

Wei L ，Zhang L ，Zhang Y ，Yan L ，Liu B ，Cao Z ，Zhao N ，He X ，Li L ，Lu C ... -  《-》