Jianpi Jieyu Decoction, An Empirical Herbal Formula, Exerts Psychotropic Effects in Association With Modulation of Gut Microbial Diversity and GABA Activity

Relationship Between Depression and Epigallocatechin Gallate from the Perspective of Gut Microbiota: A Systematic Review

Depression, a serious mental illness, is characterized by high risk, high incidence, persistence, and tendency to relapse, posing a significant burden on global health. The connection between depression and gut microbiota is an emerging field of study in psychiatry and neuroscience. Understanding the gut-brain axis is pivotal for understanding the pathogenesis and treatment of depression. Gut microbes influence depression-like behaviors by impacting the hypothalamic-pituitary-adrenal axis (HPA), monoamine neurotransmitters, immune responses, cell signaling, and metabolic pathways. Tea, widely used in clinical practice to improve neuropsychiatric disorders, contains Epigallocatechin gallate (EGCG), a major ingredient of green tea, which effectively regulates intestinal flora. This review examined the risks and causes of depression, the complications associated with intestinal flora, their role in the development and treatment of depression, and how EGCG may alleviate depression through interactions with gut microbiota and other mechanisms.

GABA, epigallocatechin gallate, tea, and the gut-brain axis

Our investigations on GABA-enriched tea and the reduction of stress in a student cohort have shown that more than just GABA may be involved. The effects of other constituents that are changed in the enrichment process are likely to be important. We have concentrated on GABA as well as the major tea flavonoid, epigallocatechin gallate. While this flavonoid is known to get to the brain on oral administration, it is far from clear that GABA does the same. GABA may act primarily on the gut and influence brain function via the gut-brain axis and the gut microbiome. In addition, there may be a microbiome in the brain that has a role. The situation is complex and not clearly understood. Mixtures of bioactive compounds are always difficult to investigate, but even the precise mechanisms of how pure oral GABA acts as a neuro-nutraceutical is unclear.

Chinese Materia Medica in Treating Depression: The Role of Intestinal Microenvironment

Depression is a highly heterogeneous mental illness. Drug treatment is currently the main therapeutic strategy used in the clinic, but its efficacy is limited by the modulation of a single target, slow onset, and side effects. The gut-brain axis is of increasing interest because intestinal microenvironment disorders increase susceptibility to depression. In turn, depression affects intestinal microenvironment homeostasis by altering intestinal tissue structure, flora abundance and metabolism, hormone secretion, neurotransmitter transmission, and immune balance. Depression falls into the category of "stagnation syndrome" according to Traditional Chinese Medicine (TCM), which further specifies that "the heart governs the spirit and is exterior-interior with the small intestine". However, the exact mechanisms of the means by which the disordered intestinal microenvironment affects depression are still unclear. Here, we present an overview of how the Chinese materia medica (CMM) protects against depression by repairing intestinal microenvironment homeostasis. We review the past five years of research progress in classical antidepressant TCM formulae and single CMMs on regulating the intestinal microenvironment for the treatment of depression. We then analyze and clarify the multitarget functions of CMM in repairing intestinal homeostasis and aim to provide a new theoretical basis for CMM clinical application in the treatment of depression.

Effects of Dietary Glycerol Monobutyrate Supplementation on Egg Performance, Biochemical Indices, and Gut Microbiota of Aged Hens

This experiment aimed to determine the effect of dietary supplementation with glycerol monobutyrate (GMB) on egg-laying performance, biochemical indicators, and gut microflora at the late stage of laying hens. A total of 252 healthy Dawu Golden Phoenix laying hens with no difference in body weight were selected and randomly divided into two groups: (1) control group (CG), corn-soybean meal diet, (2) 500 mg glycerol monobutyrate/kg added to the basal diet. Six replicates were set up for each treatment group, with 21 birds per replicate. The trial started at week 55 and lasted for 8 weeks. Compared to the control group, the supplementation with GMB increased egg weight (P = 0.03), shell thickness (P = 0.03) and decreased egg breaking rate (P = 0.04). There was no significant difference in egg production rate, feed-to-egg ratio, egg shape index, eggshell strength, and Haugh unit between the two groups. In addition, dietary GMB decreased the levels of aspartate aminotransferase (P = 0.03) and total bilirubin (P = 0.02) in serum, and increased total antioxidant capacity (P = 0.03) and total superoxide dismutase (P = 0.02). However, alpha diversity indices (Ace, Chao1, Shannon, Simpson, goods_coverage, and PD_whole tree) were not different between the two groups. Notably, dietary GMB significantly decreased the abundances of Proteobacteria at the phylum level and the abundances of Enterobacter at the genus level (P < 0.01), but there was no significant difference in the composition of other cecal microbiota. In summary, the present study revealed that supplementation with 500 mg/kg glycerol monobutyrate improved egg weight, eggshell quality, and antioxidant capacity in serum, but its effect on cecal microbiota composition was limited.

Network Pharmacology Exploration Reveals Gut Microbiota Modulation as a Common Therapeutic Mechanism for Anti-Fatigue Effect Treated with Maca Compounds Prescription

Maca compounds prescription (MCP) is a common botanical used in dietary supplements, primarily to treat exercise-induced fatigue. The aim of this study is to elucidate the multi-target mechanism of MCP on fatigue management via network pharmacology and gut microbiota analysis. Databases and literature were used to screen the chemical compounds and targets of MCP. Subsequently, 120 active ingredients and 116 fatigue-related targets played a cooperative role in managing fatigue, where several intestine-specific targets indicated the anti-fatigue mechanism of MCP might be closely related to its prebiotics of intestinal bacteria. Thus, forced swimming tests (FSTs) were carried and mice fecal samples were collected and analyzed by 16S rRNA sequencing. Gut microbiota were beneficially regulated in the MCP-treated group in phylum, genus and OTU levels, respectively, and that with a critical correlation included Lactobacillus and Candidatus Planktophila. The results systematically reveal that MCP acts against fatigue on multi-targets with different ingredients and reshapes the gut microbial ecosystem.

Anti-fatigue effect of phlorizin on exhaustive exercise-induced oxidative injury mediated by Nrf2/ARE signaling pathway in mice

Oxidative stress plays a crucial role in fatigue, thus it is of significance to develop safe and efficient antioxidant to prevent fatigue. Phlorizin (PHZ) is a major active ingredient of dihydrochalcone from Lithocarpus polystachyus Rehd., which has already been approved as a new food material in China since 2017. The current study was designed to investigate the effect of PHZ on fatigue, and further to elucidate its possible underlying mechanism. Our results revealed that PHZ exerted beneficial effect on exhaustive exercise-induced fatigue in mice, as reflected by rotarod test and exhaustive swimming test. Moreover, PHZ also effectively decreased the levels of blood urea nitrogen, creatine kinase and plasma lactic acid, increased the liver glycogen and skeletal muscle glycogen of fatigued mice, as evidenced by enzyme linked immunosorbent assay. PHZ balanced the redox status through reducing generation of reactive oxygen species, enhancing the activities of antioxidative enzymes. Furthermore, PHZ not only increased the ratio of Bcl2/Bax, but also decreased the level of cleaved-caspase 3. Notably, PHZ facilitated nuclear factor erythroid 2-related factor 2 (Nrf2) translocated from cytoplasm to nucleus, and up-regulated its downstream antioxidant response element including heme oxygenase-1 and NADPH quinone oxidoreductase-1. Intriguingly, PHZ directly bound to Nrf2, as evidenced by molecular docking, and the anti-fatigue effects of PHZ were almost abolished in Nrf2 deficient mice. In summary, our findings suggest that PHZ might be a natural occurring antioxidant with safety profile to relieve fatigue via targeting Nrf2 to inhibit apoptosis.