Guiqi Baizhu Decoction Alleviates Radiation Inflammation in Rats by Modulating the Composition of the Gut Microbiota

The gut microbiota is important in metabolism and immune modulation, and compositional disruption of the gut microbiota population is closely associated with inflammation caused by ionizing radiation (IR). Guiqi Baizhu decoction (GQBZD) is a medicinal compound used in traditional Chinese medicine with anti-inflammatory and antioxidation effects, especially in the process of radiotherapy. However, the effect of GQBZD on reducing the damage to the normal immune system in radiotherapy remains unclear. Here, we show that GQBZD reduces body weights, water intake, food intake, diarrhea level and quality of life score, and inflammation and enhances immunity function in rats treated with X-ray radiation. Meanwhile, our data indicate that GQBZD not only reverses IR-induced gut dysbiosis as indicated change of α-diversity and β-diversity of microbiota, the composition of Desulfovibrio, Bacteroides, and Parabacteroides, except for Roseburia and Lachnoclostridium, but also maintains intestinal barrier integrity and promoting the formation of short-chain fatty acids (SCFAs). GQBZD can also reduce the level of phosphorylation P65 (p-P65). Our results demonstrate that GQBZD can significantly alleviate the inflammatory responses and improve the immune damage against IR, and may be used as prebiotic agents to prevent gut dysbiosis and radiation-related metabolic disorders in radiotherapy.

Potential applications of microfluidics based blood brain barrier (BBB)-on-chips for in vitro drug development

The human blood-brain barrier (BBB) is a complex multi-dimensional reticular barrier system composed of cerebral microvascular endothelial cells, pericytes, astrocytes and a variety of neurons. The conventional in vitro cell culture model fails to truly present the dynamic hemodynamics of BBB and the interaction between neurons. And it is even more impossible to explore brain-related multi-organ diseases, which brings huge obstacles to explore diseases of the central nervous system and the interaction between brain-related multi-organs, and evaluate drug efficacy. Miniaturized microfluidics based BBB chips are being commonly used to co-culture a variety of cells on a small-sized chip to construct a three-dimensional (3D) BBB or BBB-related organ disease models. By combining with other electrophysiological, biochemical sensors or equipment and imaging systems, it can in real time and quickly screen disease-related markers and evaluate drug efficacy. This review systematically summarized the research progress of in vitro BBB and BBB-related organ chips, and analyzed the obstacles of BBB models in depth. Parallelly combined with the current research trends and hot spots, we give the further improvement measures of microfluidic BBB chips.

Gut microbes in cardiovascular diseases and their potential therapeutic applications

Microbial ecosystem comprises a complex community in which bacteria interact with each other. The potential roles of the intestinal microbiome play in human health have gained considerable attention. The imbalance of gut microbial community has been looked to multiple chronic diseases. Cardiovascular diseases (CVDs) are leading causes of morbidity worldwide and are influenced by genetic and environmental factors. Recent advances have provided scientific evidence that CVD may also be attributed to gut microbiome. In this review, we highlight the complex interplay between microbes, their metabolites, and the potential influence on the generation and development of CVDs. The therapeutic potential of using intestinal microbiomes to treat CVD is also discussed. It is quite possible that gut microbes may be used for clinical treatments of CVD in the near future.

Role of gut microbiota in identification of novel TCM-derived active metabolites

Traditional Chinese Medicine (TCM) has been extensively used to ameliorate diseases in Asia for over thousands of years. However, owing to a lack of formal scientific validation, the absence of information regarding the mechanisms underlying TCMs restricts their application. After oral administration, TCM herbal ingredients frequently are not directly absorbed by the host, but rather enter the intestine to be transformed by gut microbiota. The gut microbiota is a microbial community living in animal intestines, and functions to maintain host homeostasis and health. Increasing evidences indicate that TCM herbs closely affect gut microbiota composition, which is associated with the conversion of herbal components into active metabolites. These may significantly affect the therapeutic activity of TCMs. Microbiota analyses, in conjunction with modern multiomics platforms, can together identify novel functional metabolites and form the basis of future TCM research.

A Review of the Effects of Natural Compounds, Medicinal Plants, and Mushrooms on the Gut Microbiota in Colitis and Cancer

The human gastrointestinal tract harbors a diverse array of microorganisms that play fundamental roles in health and disease. Imbalance in the gut microbiota, namely dysbiosis, can lead to various diseases, including cancer and gastrointestinal tract disorders. Approaches to improve gut dysbiosis, such as dietary intervention, intake of probiotics, and fecal microbiota transplantation are emerging strategies to treat these diseases. Various medicinal botanicals have reported anti-cancer and/or anti-inflammatory properties. Preclinical studies have illustrated that some of these natural products are also capable to modulate the gut microbiota, suggesting their use as possible alternative approach to improve gut dysbiosis and thereby assist diseases treatment. In this review article, we have summarized the current knowledge on the effects of natural compounds, medicinal plants, and mushrooms on the gut microbiota in various cancers and colitis in preclinical animal models. Challenges towards the clinical use of these medicinal botanicals as modulators of the gut microbiota in cancer and colitis treatment are also discussed.

Gegen Qinlian decoction maintains colonic mucosal homeostasis in acute/chronic ulcerative colitis via bidirectionally modulating dysregulated Notch signaling

BACKGROUND

Gegen Qinlian decoction (GQ) is a well-known traditional Chinese medicine that has been clinically proven to be effective in treating ulcerative colitis (UC). However, its therapeutic mechanism has not been fully elucidated. Notch signaling plays an essential role in the regeneration of the intestinal epithelium.

PURPOSE

This study was designed to ascertain the mechanism by which GQ participates in the recovery of the colonic mucosa by regulating Notch signaling in acute and chronic UC models.

METHODS

Acute and chronic UC mice (C57BL/6) were established with 3 and 2% dextran sulfate sodium (DSS), respectively, and treated with oral administration of GQ. The expression of the Notch target gene Hes1 and the Notch-related proteins RBP-J, MAML and Math1 was analyzed by western blotting. PTEN mRNA levels were detected by qRT-PCR. Mucin production that is characteristic of goblet cells was determined by Alcian blue/periodic acid-Schiff staining and verified by examining MUC2 mRNA levels by qRT-PCR. Cell proliferation was assayed by immunohistochemistry analysis of Ki67. HT-29 and FHC cells and Toll-like receptor 4 knockout (TLR4^-/-) acute UC mice were also used in this study.

RESULTS

GQ restored the injured colonic mucosa in both acute and chronic UC models. We found that Notch signaling was hyperactive in acute UC mice and hypoactive in chronic UC mice. GQ downregulated Hes1, RBP-J and MAML proteins and augmented goblet cells in the acute UC models, whereas GQ upregulated Hes1, RBP-J and MAML proteins in chronic UC mice, reducing goblet cell differentiation and promoting crypt base columnar (CBC) stem cell proliferation. Hes1 mRNA was suppressed in TLR4^-/- UC mice, and GQ treatment reversed this effect. In vitro, GQ reduced Hes1 protein in Notch-activated HT29 and FHC cells but increased Hes1 protein in Notch-inhibited cells.

CONCLUSIONS

GQ restored the colonic epithelium by maintaining mucosal homeostasis via bidirectional regulation of Notch signaling in acute/chronic UC models.

Phytochemical drug candidates for the modulation of peroxisome proliferator-activated receptor γ in inflammatory bowel diseases

Plant-based compounds or phytochemicals such as alkaloids, glycosides, flavonoids, volatile oils, tannins, resins, and polyphenols have been used extensively in traditional medicine for centuries and more recently in Western alternative medicine. Extensive evidence suggests that consumption of dietary polyphenolic compounds lowers the risk of inflammatory diseases. The anti-inflammatory properties of several phytochemicals are mediated through ligand-inducible peroxisome proliferator-activated receptors (PPARs), particularly the PPARγ transcription factor. Inflammatory bowel disease (IBD) is represented by ulcerative colitis, which occurs in the mucosa of the colon and rectum, and Crohn's disease (CD) that can involve any segment of gastrointestinal tract. Because of the lack of cost-effective pharmaceutical treatment options, many IBD patients seek and use alternative and unconventional therapies to alleviate their symptoms. PPARγ plays a role in the inhibition of inflammatory cytokine expression and activation of anti-inflammatory immune cells. The phytochemicals reported here are ligands that activate PPARγ, which in turn modulates inflammatory responses. PPARγ is highly expressed in the gut making it a potential therapeutic target for IBDs. This review summarizes the effects of the currently published phytochemicals that modulate the PPARγ pathway and reduce or eliminate colonic inflammation.

Intestinal Microbiota-Associated Metabolites: Crucial Factors in the Effectiveness of Herbal Medicines and Diet Therapies

Although the efficacy of herbal medicines (HMs) and traditional Chinese medicines (TCMs) in human diseases has long been recognized, their development has been hindered in part by a lack of a comprehensive understanding of their mechanisms of action. Indeed, most of the compounds extracted from HMs can be metabolized into specific molecules by host microbiota and affect pharmacokinetics and toxicity. Moreover, HMs modulate the constitution of host intestinal microbiota to maintain a healthy gut ecology. Dietary interventions also show great efficacy in treating some refractory diseases, and the commensal microbiota potentially has significant implications for the high inter-individual differences observed in such responses. Herein, we mainly discuss the contribution of the intestinal microbiota to high inter-individual differences in response to HMs and TCMs, and especially the already known metabolites of the HMs produced by the intestinal microbiota. The contribution of commensal microbiota to the inter-individual differences in response to dietary therapy is also briefly discussed. This review highlights the significance of intestinal microbiota-associated metabolites to the efficiency of HMs and dietary interventions. Our review may help further identify the mechanisms leading to the inter-individual differences in the effectiveness of HM and dietary intervention from the perspective of their interactions with the intestinal microbiota.

Gut microbiota modulation with traditional Chinese medicine: A system biology-driven approach

With the development of system biology, traditional Chinese medicine (TCM) is drawing more and more attention nowadays. However, there are still many enigmas behind this ancient medical system because of the arcane theory and complex mechanism of actions. In recent decades, advancements in genome sequencing technologies, bioinformatics and culturomics have led to the groundbreaking characterization of the gut microbiota, a 'forgotten organ', and its role in host health and disease. Notably, gut microbiota has been emerging as a new avenue to understanding TCM. In this review, we will focus on the structure, composition, functionality and metabolites of gut microbiota affected by TCM so as to conversely understand its theory and mechanisms. We will also discuss the potential areas of gut microbiota for exploring Chinese material medica waste, Chinese marine material medica, add-on therapy and personalized precise medication of TCM. The review will conclude with future perspectives and challenges of gut microbiota in TCM intervention.

Gut microbiota in phytopharmacology: A comprehensive overview of concepts, reciprocal interactions, biotransformations and mode of actions

The dynamic and delicate interactions amongst intestinal microbiota, metabolome and metabolism dictates human health and disease. In recent years, our understanding of gut microbial regulation of intestinal immunometabolic and redox homeostasis have evolved mainly out of in vivo studies associated with high-fat feeding induced metabolic diseases. Techniques utilizing fecal transplantation and germ-free mice have been instrumental in reproducibly demonstrating how the gut microbiota affects disease pathogenesis. However, the pillars of modern drug discovery i.e. evidence-based pharmacological studies critically lack focus on intestinal microflora. This is primarily due to targeted in vitro molecular-approaches at cellular-level that largely overlook the etiology of disease pathogenesis from the physiological perspective. Thus, this review aims to provide a comprehensive understanding of the key notions of intestinal microbiota and dysbiosis, and highlight the microbiota-phytochemical bidirectional interactions that affects bioavailability and bioactivity of parent phytochemicals and their metabolites. Potentially by focusing on the three major aspects of gut microbiota i.e. microbial abundance, diversity, and functions, I will discuss phytochemical-microbiota reciprocal interactions, biotransformation of phytochemicals and plant-derived drugs, and pre-clinical and clinical efficacies of herbal medicine on dysbiosis. Additionally, in relation to phytochemical pharmacology, I will briefly discuss the role of dietary-patterns associated with changes in microbial profiles and review pharmacological study models considering possible microbial effects. This review therefore, emphasize on the timely and critically needed evidence-based phytochemical studies focusing on gut microbiota and will provide newer insights for future pre-clinical and clinical phytopharmacological interventions.