Fig. 2: The molecular mechanisms of Parabacteroides in various diseases.
From: Parabacteroides as a promising target for disease intervention: current stage and pending issues
a Obesity: P. goldsteinii could alleviate obesity by increasing the thermogenesis of adipose tissue. P. distasonis significantly alters the bile acid profile and elevates the level of succinate in the gut, thereby facilitating lipid metabolism and glucose metabolism. b Diabetes mellitus: P. distasonis augments the production of its metabolites, namely indoleacrylic acid, nicotinic acid, and TDUAC, thereby activating the AhR signaling pathway, intestinal GPR109a, and regulating glucose tolerance and insulin sensitivity, thereby ameliorating diabetes and its complications. c Depression: The specific mechanism by which Parabacteroides affects the occurrence and development of depression is highly complex, and it might exert its role through metabolites such as GABA and IAld. d Neurological disorders: Parabacteroides can affect a variety of neurological diseases, including Alzheimer’s disease, Parkinson’s disease, epilepsy, autism spectrum disorder, amyotrophic lateral sclerosis, and multiple sclerosis. e Gut barrier and intestinal inflammation: Parabacteroides is capable of promoting intestinal self-repair and ameliorating intestinal inflammation by reducing the production of pro-inflammatory cytokines, down-regulating the NF-κB pathway, facilitating Wnt signaling, and increasing the mRNA level of tight junction proteins. f Tumor: Parabacteroides could inhibit tumor growth by enhancing anti-tumor immune responses, particularly the anti-tumor immunity represented by ICIs. (FBP fructose-1,6-bisphosphate, FBPase fructose-1,6-bisphosphatase, F6P fructose-6-phosphate, Glu6P glucose-6-phosphate, IGN intestinal gluconeogenesis, CA cholic acid, LCA lithocholic acid, FGF15 fibroblast growth factor 15, CDCA chenodeoxycholic acid, UDCA ursodesoxycholic acid, NLRP3 NOD-like receptor, thermal protein domain associated protein 3).
