Tianhuang formula reduces the oxidative stress response of NAFLD by regulating the gut microbiome in mice

Abstract

BackgroundThe gut microbiome affects the occurrence and development of NAFLD, but its mechanism has not yet been fully elucidated. Chinese medicine is a new treatment strategy to improve NAFLD by regulating the gut microbiome. Tianhuang formula (TH) has been proved to have a lipid-lowering effect in which constituents of ginsenoside Rb1, ginsenoside Rg1, ginsenoside Rb, ginsenoside Re, and ginsenoside R1 from Panax notoginseng and berberine, palmatine, and coptisine from Coptis chinensis have low drug permeability, which results in poor intestinal absorption into the human body, and are thus able to come into contact with the gut microflora for a longer time. Therefore, it might be able to influence the gut microbial ecosystem, but it still needs to be investigated.MethodThe characteristics of the gut microbiome were represented by 16S rRNA sequencing, and the metabolites in intestinal contents and liver were discovered by non-targeted metabolomics. Correlation analysis and fermentation experiments revealed the relationship between the gut microbiome and metabolites. Blood biochemical indicators, liver function indicators, and oxidation-related indicators were assayed. H&E staining and Oil Red O staining were used to analyze the characteristics of hepatic steatosis. RT-qPCR and western blotting were used to detect the expression of genes and proteins in liver tissues, and fecal microbial transplantation (FMT) was performed to verify the role of the gut microbiome.ResultsGut microbiome especially Lactobacillus reduced, metabolites such as 5-Methoxyindoleacetate (5-MIAA) significantly reduced in the liver and intestinal contents, the level of hepatic GSH and SOD reduced, MDA increased, and the protein expression of Nrf2 also reduced in NAFLD mice induced by high-fat diet (HFD). The normal diet mice transplanted with NAFLD mice feces showed oxidative liver injury, indicating that the NAFLD was closely related to the gut microbiome. TH and TH-treated mice feces both can reshape the gut microbiome, increase the abundance of Lactobacillus and the content of 5-MIAA in intestinal contents and liver, and improve oxidative liver injury. This indicated that the effect of TH improving NAFLD was related to the gut microbiome, especially Lactobacillus. 5-MIAA, produced by Lactobacillus, was proved with fermentation experiments in vitro. Further experiments proved that 5-MIAA activated the Nrf2 pathway to improve oxidative stress in NAFLD mice induced by HFD. TH reshaped the gut microbiome, increased the abundance of Lactobacillus and its metabolite 5-MIAA to alleviate oxidative stress, and improved NAFLD.ConclusionThe study has demonstrated a mechanism by which the gut microbiome modulated oxidative stress in NAFLD mice induced by HFD. The traditional Chinese medicine TH improved NAFLD by regulating the gut microbiome, and its mechanism was related to the “Lactobacillus-5-MIAA-Nrf2” pathway. It provided a promising way for the intervention of NAFLD.

The dysfunction in intestinal microorganisms and enzyme activity as significant contributors to diarrhea with kidney-yang deficiency syndrome

“…Elevated biomarkers of oxidative damage do not consistently signify heightened oxidative stress; they may also result from malfunctioning repair or replacement systems ( Halliwell, 2007 ). Research indicates that the Tianhuang formula can enhance Lactobacillus abundance, along with its metabolite 5-methoxyindole acetic acid, thereby reducing oxidative stress and ameliorating Non-alcoholic fatty liver disease (NAFLD) through the regulation of gut microbiota ( Luo et al, 2022 ). L. paracasei Jlus66 (Jlus66), a probiotic isolated from “milk bumps,” enhances the abundance of Gram-positive bacteria like Firmicutes in the gut microbiota.…”

Decoding the role of immune T cells: A new territory for improvement of metabolic‐associated fatty liver disease

“…For instance, inulin originating from plants alleviated diet‐induced barrier dysfunction by increasing antimicrobial peptides and decreasing the luminal bacteria of Ileum in western‐style diet (WSD) mice [ 180 ]. Tianhuang formula chiefly consists of Panax notoginseng and Coptis chinensis , and reshaped the intestinal flora such as increasing Lactobacillus and its metabolites to improve HFD‐induced MAFLD [ 181 ]. In addition to being influenced by TCM, the gut microbiota is closely related to the immune microenvironment and also has the potential to become a possible effective treatment approach for MAFLD [ 182 , 183 ].…”

Exploring global research status and trends in anti-obesity effects of traditional Chinese medicine through intestinal microbiota: a bibliometric study

“…These findings hold significance in exploring the role of traditional Chinese medicine ingredients in microbiota regulation and health promotion (Sun et al, 2019). Besides, the Tianhuang formula can increase the abundance of Lactobacillus in the gut and liver and 5-Methoxyindoleacetate (5-MIAA), activate NF2, and reduce the expression of oxidative markers GCLC, NQO1, and TXR1 (Luo et al, 2022). Interestingly, TCM can produce effects similar to prebiotics even at doses much lower than those typically used for conventional prebiotics (Anhêet al, 2015b).…”