Soyasaponin A2 Alleviates Steatohepatitis Possibly through Regulating Bile Acids and Gut Microbiota in the Methionine and Choline-Deficient (MCD) Diet-induced Nonalcoholic Steatohepatitis (NASH) Mice

Traditional Mongolian Medicine Qiqirigan-8 alleviates non-alcoholic fatty liver disease via restoring gut microbiota and metabolism

Background

Mongolian Medicine Qiqirigan-8 (MMQ-8) is a traditional Mongolian medicine formula used to treat fatty liver disease. However, the material basis and in vivo metabolic process of the therapeutic effect of MMQ-8 on non-alcoholic fatty liver disease (NAFLD) remain unclear.

Methods

The chemical composition of MMQ-8 was determined using Ultra-high-performance liquid chromatography-quadrupole Exactive Mass spectrometry analysis (UHPLC-QE-MS). C57BL/6J mice were fed a choline-deficient diet for 12 weeks to induce a NAFLD model. Hematoxylin and Eosin (H&E)-staining, combined with serum biochemical indexes, was used to observe liver appearance and characterize the pathological changes and functions of the liver. HE staining and Alcian Blue-Phosphoric Acid Schiff (AB-PAS) staining of the colon, along with ZO-1 immunofluorescence expression in the colon were used to reveal the effect of MMQ-8 on the disruption of the intestinal epithelial mucosal barrier in the NAFLD. The expression of intestinal tight junction genes was analyzed by qRT-PCR to observe the protective effect of MMQ-8 against intestinal epithelial mucosal barrier disruption. Fecal metagenomics and serum non-targeted metabolomics were used to reveal the effects of MMQ-8 on the gut microbiota and metabolism in mice with NAFLD. Finally, we emphasize the interaction between gut microbiota and metabolites through Spearman correlation coefficient analysis.

Results

Mongolian Medicine Qiqirigan-8 contains 17 active ingredients, which can reduce hepatic steatosis and lobular inflammation in mice with NAFLD, and have protective effects against liver injury. MMQ-8 reduced the infiltration of inflammatory cells in the colon epithelium of model mice while restoring the number of goblet cells. MMQ-8 significantly enhanced ZO-1 protein expression in the colon, as well as the mRNA expression of both ZO-1 and Occludin. Fecal metagenomics results showed that MMQ-8 reduced the Bacillota/Bacteroidota ratio in NAFLD mice. Increased the abundance of beneficial bacteria such as Porphyromonadaceae, Prevotella, and Bacteroidota. and suppressed the abundance of dysfunctional bacteria, such as Bacillota, Acetatifactor, and Erysipelotrichaceae. Furthermore, metabolomics studies revealed that MMQ-8 intervention significantly regulated the expression of metabolites related to glutathione metabolism, butyric acid metabolism, sphingolipid metabolism, and glycerophospholipid metabolism in NAFLD mice compared to the model group. These metabolic pathways play key roles in NAFLD. According to Spearman's correlation coefficient analysis, up-regulation of Porphyromonadaceae, Prevotella, and Bacteroidota after MMQ-8 intervention was negatively correlated with LPC levels in glycerophospholipid metabolic pathways, while positively correlated with PC levels. In contrast, the relationship between Bacillota and Acetatifactor, which were down-regulated after MMQ-8 intervention, was the opposite. In addition, the up-regulation of Porphyromonadaceae, Prevotella, and Bacteroidota after MMQ-8 intervention was positively correlated with fumaric acid, 2-oxoglutaric acid, adenosine, and L-glutathione levels, while those down-regulated after MMQ-8 intervention were positively correlated with the levels of Bacillota, Acetatifactor were negatively correlated with all the above metabolites. Thus, glutathione metabolism, butyric acid metabolism, sphingolipid metabolism, glycerophospholipid metabolism and gut microbial ecosystem are tightly intertwined in this process.

Conclusion

In summary, these findings indicate that MMQ-8 has a synergistic anti-NAFLD effect through its multi-component, multi-target, gut microbiota-modulating and multi metabolic pathway characteristics. The host's regulation of specific gut microbiota and involvement in multiple metabolic pathways may be one of the important mechanisms by which MMQ-8 exerts its therapeutic effects on NAFLD. It is worth noting that metabolic pathways such as glutathione metabolism, butyric acid metabolism, sphingolipid metabolism, glycerophospholipid metabolism, and the gut microbiota ecosystem are closely intertwined in this process.

Broccoli (Brassica oleracea L. var. italica Planch) alleviates metabolic-associated fatty liver disease through regulating gut flora and lipid metabolism via the FXR/LXR signaling pathway

The increased consumption of dietary fats contributes to the development of MAFLD (metabolic fatty liver disease). The ability of broccoli to enhance lipid metabolism has attracted researchers' attention. Researchers fed C57BL/6 mice a 12-week HFD to ensure the induction of MAFLD. The findings indicated that broccoli floret juice could effectively relieve MAFLD. Broccoli is helpful for reducing weight, blood glucose levels, fat accumulation, and insulin resistance associated with MAFLD and reduces the concentrations of TC, TG, LDL-C, GOT, GPT, IL-1β, IL-6, CCL4, and MCP1. Broccoli can increase the concentration of HDL-C, CAT, GSH-Px, SOD, and T-AOC, relieve inflammation and hepatic and ileum damage, and improve the antioxidant capacity of the body. Also, broccoli can optimize the structure of intestinal flora, promote the growth of Allobaculum, Muribaculaceae, Akkermansia, Eubacterium, and Bacteroides, and reduce bile acid deposition. In addition, the FXR/LXRα signaling system is impacted by broccoli, which is capable of raising the average levels of expression of the Fxr, SHP, and Cyp7a1 genes and proteins and reducing those of the genes for Fasn, Lpin 1, Dgat 2, Scd1, LXRα, and SREBP-1c.

Ginsenosides From Panax ginseng Improves Hepatic Lipid Metabolism Disorders in HFD-Fed Rats by Regulating Gut Microbiota and Cholesterol Metabolism Signaling Pathways

A high-fat diet (HFD) is often associated with hepatic lipid metabolism disorders, leading to dysfunction in multiple body systems. Ginsenosides derived from Panax ginseng have been reported to possess potential effects in ameliorating lipid metabolism disorders; however, their underlying mechanisms remain insufficiently explored. This study aims to investigate the bioactivities of ginsenosides in combating lipid metabolism disorders and obesity, with a focus on their mechanisms involving the cholesterol metabolism signaling pathway and gut microbiota. Our results demonstrated that ginsenoside treatment significantly reduced overall body weight, body weight changes, liver weight, and eWAT weight, as well as alleviated hepatic steatosis and dyslipidemia in HFD-fed rats, without affecting food intake. These effects were dose-dependent. Furthermore, 16S rRNA sequencing revealed that ginsenosides significantly increased the relative abundance of Akkermansia muciniphila, Blautia, Eisenbergiella, Clostridium clusters XI, XVIII, and III, while decreasing the relative abundance of Clostridium subcluster XIVa and Dorea. In addition, ginsenoside treatment significantly regulated the expression of hepatic genes and proteins involved in the cholesterol metabolism signaling pathway (FXR, CYP7A1, CYP7B1, CYP27A1, ABCG5, ABCG8, Insig2, and Dhcr7), potentially inhibiting hepatic cholesterol biosynthesis while promoting cholesterol transport to HDL and its excretion via bile and feces. Notably, levels of 7-dehydrocholesterol (7-DHC) and 27-hydroxycholesterol (27-OHC) were reduced, while 5β,6β-epoxycholesterol (5,6β-epoxy) levels were elevated following ginsenoside treatment, indicating significant modulation of oxysterols by ginsenosides. Moreover, bile acid enterohepatic circulation was regulated through the enhancement of hepatic FXR-CYP7A1 signaling and intestinal FXR-FGF15 signaling in HFD-fed rats treated with ginsenosides, which was closely linked to gut microbiota composition. Collectively, our findings suggest that ginsenosides alleviate hepatic lipid metabolism disorders by modulating gut microbiota and the cholesterol metabolism signaling pathway in HFD-fed rats.

Tetrahydrocurcumin Alleviates Metabolic Dysfunction-Associated Steatohepatitis in Mice by Regulating Serum Lipids, Bile Acids, and Gut Microbiota

The aim of this study was to investigate the protective effects and potential mechanisms of Tetrahydrocurcumin (THC) on methionine-choline-deficient diet (MCD)-induced MASH in C57BL/6 mice by using multi-omics techniques. The C57BL/6 mice were fed with the MCD for 8 weeks to establish a MASH model, while THC (100 mg·kg-1·d-1) and obeticholic acid (6.5 mg·kg-1·d-1) were administered via gavage to the THC group and the positive control group, respectively. The biochemical indexes of the serum and liver were detected using kits. Liver tissue sections were taken to observe the pathomorphological changes. Serum lipid and bile acid contents were measured via LC-MS, and the changes in ileal intestinal flora were detected by 16S rDNA high-throughput sequencing technology. The results revealed that THC significantly attenuated oxidative stress and lipid accumulation in NCTC-1469 cells and relieved hepatic injury and oxidative stress, reduced hepatic TG content, and improved hepatic steatosis in mice. THC alleviated 34 lipid abnormalities caused by the MCD; increased the abundance and diversity of intestinal flora, the ratio of Firmicutes to Bacteroidota, and the abundance of the probiotic (Verrucomicrobiota, Christensenellaceae, Akkermansiaceae, Lachnospiraceae, Desulfovibrionaceae); and reduced the abundance of obesity-associated pathogenic flora such as Firmicutes. Bile acid analysis showed that THC administration reduced the levels of serum toxic bile acid 7-KDCA and CA. In addition, RT-qPCR studies showed that THC down-regulated the transcript levels of the hepatic lipogenesis-related genes Srebp1c, Acc1, Scd1, and Fas, and up-regulated the transcript levels of the hepatic bile acid secretion-related genes Mrp2 and Bsep. The above results suggest that THC may alleviate MCD-induced MASH by downregulating liver Srebp1c, Acc1, Scd1, and Fas levels to inhibit lipid synthesis, upregulating Mrp2 and Bsep levels to regulate serum toxic BA levels, up-regulating the abundance of intestinal probiotic flora, and down-regulating the abundance of intestinal harmful bacterial flora. The multi-omics findings from the above study identified potential new mechanisms by which THC alleviates MASH, providing new reference targets for the development of anti-MASH drugs. These results also offer a basis for screening clinical diagnostic biomarkers for MASH and provide new directions for personalized diagnosis and treatment.

Sulforaphane Improves Liver Metabolism and Gut Microbiota in Circadian Rhythm Disorder Mice Models Fed With High-Fat Diets

SCOPE

This study aims to investigate the effect of sulforaphane (SFN) on hepatic metabolism and gut microbiota in a shifted circadian rhythm (CR) mouse model fed with a high-fat diet (HFD).

METHODS AND RESULTS

A shifted CR mouse model with HFD is constructed. Biochemical analyses are used to evaluate the effects of SFN on lipid accumulation and liver function. Targeted metabolomics is used for liver metabolites. Results from hematoxylin and eosin staining and Oil Red O staining show that SFN improves liver lipid accumulation and intestinal inflammatory damage in shifted CR treatment with HFD. The concentrations of amino acid metabolites are increased, and the levels of bile acid metabolites are significantly decreased by SFN treatment. Results from 16S rRNA gene sequencing indicate that SFN modulates gut microbiota, particularly by enhancing beneficial bacteria such as Lachnospiraceae, Lactobacillus, Alistipes, Akkermansia, and Eubacteriaum coprostanoligenes. Correlation analysis confirms a close relationship between intestinal microbiota and hepatic metabolites. SFN significantly regulates CR protein expression in the hypothalamus and liver tissues.

CONCLUSION

SFN alleviates hepatic metabolic disorder and gut microbiota dysbiosis induced by CR disruption under a high-fat diet in a mouse model, indicating the potential of SFN in regulating CR disruption.

Immunobiotic Bacteria Attenuate Hepatic Fibrosis through the Modulation of Gut Microbiota and the Activation of Aryl-Hydrocarbon Receptors Pathway in Non-Alcoholic Steatohepatitis Mice

SCOPE

Nonalcoholic steatohepatitis (NASH) is a leading cause of chronic liver disease worldwide that can progress to liver fibrosis (LF). Probiotics have beneficial roles in reducing intestinal inflammation and gut-associated diseases, but their effects and mechanisms beyond the gut in attenuating the progression of LF are remained unclear.

METHODS AND RESULTS

In a mouse model of NASH/LF induced by a methionine-choline deficient (MCD) diet, immunobiotics are administered to investigate their therapeutic effects. Results show that the MCD diet leads to liver inflammation, steatosis, and fibrosis, which are alleviated by immunobiotics. Immunobiotics reduces serum endotoxin and inflammatory markers while increasing regulatory cytokines and liver weight. They also suppress Th17 cells, known for producing inflammatory cytokines. Furthermore, immunobiotics mitigate collagen deposition and fibrogenic signaling in the liver, while restoring gut-barrier integrity and microbiota composition. Additionally, immunobiotics enhance the activation of the aryl hydrocarbon receptor (AhR) pathway in both colonic and liver tissues.

CONCLUSIONS

Overall, these results demonstrate a novel insight into the mechanisms through which immunobiotic administration improves the gut health which in turn increases the AhR pathway and inhibits HSCs activation and fibrosis progression beyond the gut in the liver tissue of NASH/LF mice.

Gut microbes combined with metabolomics reveal the protective effects of Qijia Rougan decoction against CCl4-induced hepatic fibrosis

Background: The occurrence and development of Hepatic fibrosis (HF) are closely related to the gut microbial composition and alterations in host metabolism. Qijia Rougan decoction (QJ) is a traditional Chinese medicine compound utilized clinically for the treatment of HF with remarkable clinical efficacy. However, its effect on the gut microbiota and metabolite alterations is unknown. Therefore, our objective was to examine the impact of QJ on the gut microbiota and metabolism in Carbon tetrachloride (CCl4)-induced HF. Methods: 40% CCl4 was used to induce HF, followed by QJ administration for 6 weeks. Serum biochemical analyses, histopathology, immunohistochemistry, RT-PCR, 16S rRNA gene sequencing, and non-targeted metabolomics techniques were employed in this study to investigate the interventional effects of QJ on a CCl4-induced HF model in rats. Results: This study demonstrated that QJ could effectively ameliorate CCl4-induced hepatic inflammation and fibrosis. Moreover, QJ upregulated the expression of intestinal tight junction proteins (TJPs) and notably altered the abundance of some gut microbes, for example, 10 genera closely associated with HF-related indicators and TJPs. In addition, metabolomics found 37 key metabolites responded to QJ treatment and strongly associated with HF-related indices and TJPs. Furthermore, a tight relation between 10 genera and 37 metabolites was found post correlation analysis. Among them, Turicibacter, Faecalibaculum, Prevotellaceae UCG 001, and unclassified Peptococcaceae may serve as the core gut microbes of QJ that inhibit HF. Conclusion: These results suggest that QJ ameliorates hepatic inflammation and fibrosis, which may be achieved by improving intestinal tight junctions and modulating gut microbiota composition as well as modulating host metabolism.

Saponins from Chenopodium quinoa Willd. husks alleviated high-fat-diet-induced hyperlipidemia via modulating the gut microbiota and multiple metabolic pathways

BACKGROUND

Hyperlipidemia is characterized by abnormally elevated blood lipids. Quinoa saponins (QS) have multiple pharmacological activities, including antitumor, bactericidal and immune-enhancing effects. However, the lipid-lowering effect and mechanisms of QS in vivo have been scarcely reported.

METHODS

The effect of QS against hyperlipidemia induced by high-fat diet in rats was explored based on gut microbiota and serum non-targeted metabolomics.

RESULTS

The study demonstrated that the supplementation of QS could reduce serum lipids, body weight, liver injury and inflammation. 16S rRNA sequencing demonstrated that QS mildly increased alpha-diversity, altered the overall structure of intestinal flora, decreased the relative richness of Firmicutes, the ratio of Firmicutes/Bacteroidetes (P < 0.05) and increased the relative richness of Actinobacteria, Bacteroidetes, Bifidobacterium, Roseburia and Coprococcus (P < 0.05). Simultaneously, metabolomics analysis showed that QS altered serum functional metabolites with respect to bile acid biosynthesis, arachidonic acid metabolism and taurine and hypotaurine metabolism, which were closely related to bile acid metabolism and fatty acid β-oxidation. Furthermore, QS increased protein levels of farnesoid X receptor, peroxisome proliferator-activated receptor α and carnitine palmitoyltransferase 1, which were related to the screened metabolic pathways. Spearman correlation analysis showed that there was a correlation between gut microbiota and differential metabolites.

CONCLUSION

QS could prevent lipid metabolism disorders in hyperlipidemic rats, which may be closely associated with the regulation of the gut microbiota and multiple metabolic pathways. This study may provide new evidence for QS as natural active substances for the prevention of hyperlipidemia. © 2023 Society of Chemical Industry.

Effects of plant natural products on metabolic-associated fatty liver disease and the underlying mechanisms: a narrative review with a focus on the modulation of the gut microbiota

Metabolic-associated fatty liver disease (MAFLD) is a chronic liver disease characterized by the excessive accumulation of fat in hepatocytes. However, due to the complex pathogenesis of MAFLD, there are no officially approved drugs for treatment. Therefore, there is an urgent need to find safe and effective anti-MAFLD drugs. Recently, the relationship between the gut microbiota and MAFLD has been widely recognized, and treating MAFLD by regulating the gut microbiota may be a new therapeutic strategy. Natural products, especially plant natural products, have attracted much attention in the treatment of MAFLD due to their multiple targets and pathways and few side effects. Moreover, the structure and function of the gut microbiota can be influenced by exposure to plant natural products. However, the effects of plant natural products on MAFLD through targeting of the gut microbiota and the underlying mechanisms are poorly understood. Based on the above information and to address the potential therapeutic role of plant natural products in MAFLD, we systematically summarize the effects and mechanisms of action of plant natural products in the prevention and treatment of MAFLD through targeting of the gut microbiota. This narrative review provides feasible ideas for further exploration of safer and more effective natural drugs for the prevention and treatment of MAFLD.

Bifidobacterium animalis subsp. lactis F1-7 Alleviates Lipid Accumulation in Atherosclerotic Mice via Modulating Bile Acid Metabolites to Downregulate Intestinal FXR

The dysfunction of intestinal microbiota and bile acid metabolism is related to the pathogenesis of atherosclerosis. This study we explored the mechanism of Bifidobacterium animalis subsp. lactis F1-7 (Bif. animalis F1-7), improving atherosclerosis by regulating the bile acid metabolism and intestinal microbiota in the ApoE-/- mice. The Bif. animalis F1-7 effectively reduced aortic plaque accumulation and improved the serum and liver lipid levels in atherosclerotic mice. The untargeted metabolomics revealed that Bif. animalis F1-7 reduced the glycine-conjugated bile acids and the levels of differential metabolite lithocholic acid (LCA) significantly. Downregulation of LCA decreased the intestinal levels of the farnesoid X-activated receptor (FXR) and regulated the bile acid metabolism through the FXR/FGF15/CYP7A1 pathway. Furthermore, the 16srRNA gene sequencing analysis revealed that structural changes in intestinal microbiota with an increase in the abundance of Bifidobacterium, Lactobacillus, Faecalibaculum, Desulfovibrio, and a decrease in Dubosiella, Clostridium_sensu_stricto_1, and Turicibacter following the Bif. animalis F1-7 intervention. Correlation analysis showed that the changes in intestinal microbiota mentioned above were significantly correlated with bile acid metabolism in atherosclerotic mice. In conclusion, this study sheds light on the mechanisms by which Bif. animalis F1-7 regulates atherosclerosis.

Gut Microbiota Plays Essential Roles in Soyasaponin's Preventive Bioactivities against Steatohepatitis in the Methionine and Choline Deficient (MCD) Diet-Induced Non-Alcoholic Steatohepatitis (NASH) Mice

SCOPE

Gut microbiota (GM) is involved in nonalcoholic steatohepatitis (NASH) development. Phytochemicals soyasaponins can prevent NASH possibly by modulating GM. This study aims to investigate the preventive bioactivities of soyasaponin monomers (SS-A1 and SS-Bb) against NASH and explores the mechanisms by targeting GM.

METHODS AND RESULTS

Male C57BL/6 mice are fed with methionine and choline deficient (MCD) diet containing SS-A1 , SS-Bb, or not for 16 weeks. Antibiotics-treated pseudo germ-free (PGF) mice are fed with MCD diet containing SS-A1 , SS-Bb, or not for 8 weeks. GM is determined by 16S rRNA amplicon sequencing. Bile acids (BAs) are measured by UPLC-MS/MS. In NASH mice, SS-A1 and SS-Bb alleviate steatohepatitis and fibrosis, reduce ALT, AST, and LPS in serum, decrease TNF-α, IL-6, α-SMA, triglycerides, and cholesterol in liver. SS-A1 and SS-Bb decrease Firmicutes, Erysipelotrichaceae, unidentified-Clostridiales, Eggerthellaceae, Atopobiaceae, Aerococcus, Jeotgalicoccus, Gemella, Rikenella, increase Proteobacteria, Verrucomicrobia, Akkermansiaceae, Romboutsia, and Roseburia. SS-A1 and SS-Bb alter BAs composition in liver, serum, and feces, activate farnesoid X receptor (FXR) in liver and ileum, increase occludin and ZO-1 in intestine. However, GM clearance abrogates the preventive bioactivities of SS-A1 and SS-Bb against NASH.

CONCLUSION

GM plays essential roles in soyasaponin's preventive bioactivities against steatohepatitis in MCD diet-induced NASH mice.

Therapeutic Role of Polyphenol Extract from Prunus cerasifera Ehrhart on Non-Alcoholic Fatty Liver

Prunus cerasifera Ehrhart (P. cerasifera) flourishes uniquely in the arid landscapes of Xinjiang, China. Preliminary studies have revealed the therapeutic potential of its polyphenol extract (PPE) in mitigating liver lipid accumulation in mice fed a high-fat diet. We established a mouse model that was subjected to a continuous high-fat diet for 24 weeks and administered PPE to investigate the effects of PPE on cholesterol and BA metabolism in NAFLD mice. The results showed that PPE administration (200 and 400 mg/kg/day, BW) led to a reduction in liver TC, an increase in liver T-BAs, and normalization of the disrupted fecal BA profile. Concurrently, it decreased levels of lipotoxic BAs and inhibited hepatic cholesterol synthesis (evidenced by reduced HMGCR activity) and intestinal cholesterol absorption (indicated by lower ACAT2 levels) while enhancing intestinal cholesterol efflux (via LXRα, ABCA1, ABCG5, and ABCG8) and stimulating hepatic BA synthesis (CYP7A1, CYP27A1) and secretion (BSEP). PPE thus led to a significant reduction in lipotoxic BAs metabolized by gut microbiota and a downregulation of the BA secretion pathway under its influence. Our findings reveal the therapeutic effect of PPE on NAFLD mice via regulating cholesterol and BA metabolism, providing a theoretical basis for exploring the potential functions of P. cerasifera.

Naringenin prevents non-alcoholic steatohepatitis by modulating the host metabolome and intestinal microbiome in MCD diet-fed mice

Non-alcoholic steatohepatitis (NASH) is a severe inflammatory phase of the non-alcoholic fatty liver disease (NAFLD) spectrum and can progress to advanced stages of NAFLD if left untreated. This study uses multi-omics data to elucidate the underlying mechanism of naringenin's reported benefit in alleviating (NASH). Male mice were fed a NASH-inducing (methionine-choline-deficient) MCD diet with or without naringenin supplementation for 6 weeks. Naringenin prevented NASH-induced histopathological liver damage and reversed the abnormal levels of hepatic triglyceride (TG)/total cholesterol (TC), serum TG/TC, serum alanine aminotransferase/aspartate transaminase, and hepatic malondialdehyde and glutathione. Importantly, naringenin intervention significantly modulated the relative abundance of gut microbiota and the host metabolomic profile. We detected more than 700 metabolites in the serum and found that the gut genus levels of Anaeroplasma and the [Eubacterium] nodatum group were closely associated with xanthine, 2-picoline, and securinine, respectively. Tuzzerella alterations showed the highest number of associations with host endogenous metabolites such as FAHFA (8:0/10:0), FFA (20:2), carnitine C8:1, tridecanedioic acid, securinine, acetylvaline, DL-O-tyrosine, and Phe-Asn. This study indicates that the interplay between host serum metabolites and gut microbiota may contribute to the therapeutic effect of naringenin against NASH.

Effects of food emulsifiers on high fat-diet-induced obesity, intestinal inflammation, changes in bile acid profile, and liver dysfunction

Obesity has become one of the most prevalent health concerns of our time. A long-term high-fat diet is closely related to obesity. Food emulsifiers are incorporated into high-fat foods to enhance the texture and stability. Whether food emulsifiers exacerbate obesity and metabolic disorders induced by a high-fat diet remains unclear. This study aimed to investigate the effects of polysorbate-80 (P80) and polyglycerol polyricinoleate (PGPR) on lipid metabolism, bile acid profile, and gut microbiota in normal and high-fat-diet-induced obesity in mice. The results of this study showed that P80 and PGPR had little effect on body weight but significantly increased epididymal-fat weight, total energy intake, and blood lipid levels. P80 and PGPR stimulated colon inflammation and improved the expression of inflammatory factors in the colon and liver significantly. P80 and PGPR changed the bile acid profile. However, P80 and PGPR did not aggravate inflammation, obesity and alter bile acid profile by altering the composition of the gut microbiota. The results of this study provide an experimental reference for the rational use of food additives and the adjustment of dietary structure, which are important and have application value.

Intermittent Fasting Alleviates Non-Alcoholic Steatohepatitis by Regulating Bile Acid Metabolism and Promoting Fecal Bile Acid Excretion in High-Fat and High-Cholesterol Diet Fed Mice

SCOPE

Intermittent fasting (IF) has a protective role across a wide range of chronic disorders, including obesity, diabetes, and cardiovascular disease, but its protection against non-alcoholic steatohepatitis (NASH) is still lacking. This study seeks to investigate how IF alleviates NASH by regulating gut microbiota and bile acids (BAs) composition.

METHODS AND RESULTS

Male C57BL/6 mice are fed a high-fat and high-cholesterol (HFHC) diet for 16 weeks to establish a NASH model. Mice then continued HFHC feeding and are treated with or without every other day fasting for 10 weeks. Hepatic pathology is assessed using hematoxylin-eosin staining. Gut microbiota of the cecum are profiled using 16S rDNA gene sequencing and the levels of BAs in serum, colon contents, and feces are measured using ultra-performance liquid chromatography-tandem mass spectrometry. Results indicate that IF significantly decreases murine body weight, insulin resistance, hepatic steatosis, ballooning, and lobular inflammation. IF reshapes the gut microbiota, reduces the accumulation of serum BAs, and increases total colonic and fecal BAs. Moreover, IF increases the expression of cholesterol 7α-hydroxylase 1 in liver, but decreases the expressions of both farnesoid-X-receptor and fibroblast growth factor 15 in the ileum.

CONCLUSION

IF alleviates NASH by regulating bile acid metabolism and promoting fecal bile acid excretion.

Gut microbiota and bile acids partially mediate the improvement of fibroblast growth factor 21 on methionine-choline-deficient diet-induced non-alcoholic fatty liver disease mice

Non-alcoholic fatty liver disease (NAFLD) is characterized by hepatic steatosis, inflammation, and fibrosis, as well as gut dysbiosis. Fibroblast growth factor 21 (FGF21), which regulates glucose and lipid metabolism, has been proven to have a good effect on NAFLD. However, the modulating process between FGF21 and gut microbiota remains unclear in treating NAFLD. Here, the fecal microbiota composition of 30 patients with NAFLD who had undergone liver biopsy and 29 matched healthy participants were studied, together with the fecal bile acid (BA) profile. Treatment with FGF21 was given in methionine-choline-deficient (MCD) diet-induced NAFLD model C57BL/6 mice. An antibiotic cocktail and fecal microbiota transplantation were used to further confirm the benefits of FGF21 that were partially attributable to the change in gut microbiota. Patients with NAFLD had higher serum FGF21 levels and dysregulated fecal microbiota compositions and fecal BA profiles. In NAFLD mice, FGF21 significantly reduced steatohepatitis and collagen deposition in vivo and restored intestinal structure. FGF21 treatment also changed gut microbiota composition and regulated dysbiosis in BA metabolism. After treatment with an antibiotic cocktail, FGF21 partially alleviated hepatic and intestinal damage in NAFLD mice. Furthermore, fecal microbiota transplantation from FGF21-treated mice showed benefits similar to FGF21 therapy. The improvement using FGF21 in MCD diet-induced NAFLD mice is partially mediated via gut microbiota and BA. Gut microbiota-regulated BA metabolism may be a potential target of FGF21 in improving NAFLD.

Dietary spirulina supplementation modifies rumen development, fermentation and bacteria composition in Hu sheep when consuming high-fat dietary

Introduction

This study aims to investigate the long-term effects of spirulina supplementation in a high-fat diet (HFD) on rumen morphology, rumen fermentation, and the composition of rumen microbiota in lambs. Spirulina is a blue-green microalgae that has been shown to have high nutritional value for livestock.

Methods

Fifty-four lambs were randomly divided into three groups: a normal chow diet (NCD) group, a high-fat diet (HFD) group, and a high-fat diet supplemented with 3% spirulina (HFD+S) group. Rumen morphology, rumen fermentation, and rumen microbiota were analyzed at the end of the study.

Results

Spirulina supplementation improved the concentration of volatile fatty acids and rumen papilla length. Additionally, there was a tendency for an increase in rumen weight and an upregulation of the genes Claudin-1, Claudin-4, and Occludin in the HFD+S group. Pyrosequencing of the 16S ribosomal RNA gene also showed that spirulina supplementation significantly changed the rumen microbiota composition in the HFD group, with a decrease in richness and diversity. Specifically, the relative abundance of Prevotella 9 and Megasphaera was significantly increased in the HFD group compared to the NCD group, while spirulina supplementation reversed these changes.

Discussion

This study suggests that 3% spirulina supplementation can improve rumen development and fermentation, and effectively relieve rumen microbe disorders in lambs caused by a high-fat diet. However, further research is needed to confirm the findings and to examine the long-term effects of spirulina supplementation in different types of livestock and under different dietary conditions.

Advances in the Bioactivities of Phytochemical Saponins in the Prevention and Treatment of Atherosclerosis

Atherosclerosis (AS) is a chronic inflammatory disease characterized by hardening and narrowing of arteries. AS leads to a number of arteriosclerotic vascular diseases including cardiovascular diseases, cerebrovascular disease and peripheral artery disease, which pose a big threat to human health. Phytochemicals are a variety of intermediate or terminal low molecular weight secondary metabolites produced during plant energy metabolism. Phytochemicals from plant foods (vegetables, fruits, whole grains) and traditional herb plants have been shown to exhibit multiple bioactivities which are beneficial for prevention and treatment against AS. Many types of phytochemicals including polyphenols, saponins, carotenoids, terpenoids, organic sulfur compounds, phytoestrogens, phytic acids and plant sterols have already been identified, among which saponins are a family of glycosidic compounds consisting of a hydrophobic aglycone (sapogenin) linked to hydrophilic sugar moieties. In recent years, studies have shown that saponins exhibit a number of biological activities such as anti-inflammation, anti-oxidation, cholesterol-lowering, immunomodulation, anti-platelet aggregation, etc., which are helpful in the prevention and treatment of AS. This review aims to summarize the recent advances in the anti-atherosclerotic bioactivities of saponins such as ginsenoside, soyasaponin, astra-galoside, glycyrrhizin, gypenoside, dioscin, saikosaponin, etc.

Astragalus mongholicus polysaccharides ameliorate hepatic lipid accumulation and inflammation as well as modulate gut microbiota in NAFLD rats

Hepatic lipid accumulation, inflammation and gut microbiota dysbiosis are hallmarks of non-alcoholic fatty liver disease (NAFLD), which is the leading cause of chronic liver disease with no therapeutic consensus. The aim of the present study was to elucidate the mechanism of the effects of Astragalus mongholicus polysaccharides (mAPS) on lipid metabolism, inflammation and gut microbiota in a rat model of NAFLD induced by a high-fat diet (HFD). Our results showed that mAPS and Berberine supplementation reduced HFD-induced increases in body weight, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and homeostasis model assessment of insulin resistance (HOMA-IR), and these changes were accompanied by improved histological changes in the liver. Moreover, administration of mAPS and Berberine resulted in lower levels of serum triglycerides, total cholesterol and low-density lipoprotein cholesterol (LDL-c) but higher levels of high-density lipoprotein cholesterol (HDL-c) in HFD-fed rats. mAPS and Berberine treatment markedly reduced HFD-induced hepatic lipid accumulation, which was associated with increased expression of phosphorylated- adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor-α (PPAR-α) but decreased expression of sterol-regulatory element binding proteins (SREBP-1). Pretreatment with mAPS or Berberine reduced HFD-induced expression of proinflammatory cytokines, such as tumor necrosis factor-α (TNF-α). In addition, mAPS downregulated the expression of colonic and hepatic Toll-like receptor 4 (TLR4) as well as phosphorylated- nuclear factor-κB (NF-κB) and nucleotide-binding domain, leucine-rich repeat-containing receptor, pyrin domain-containing-3 (NLRP3) but upregulated the expression of zonula occludens-1 (ZO-1) and occludin in HFD-fed rats. Notably, mAPS treatment reshaped the intestinal microbiome by lowering the Firmicutes to Bacteroidetes (F/B) ratio and increasing the abundance of Proteobacteria and Epsilonbacteria. mAPS supplementation had little effect on the profile of fecal short-chain fatty acids (SCFAs), but it significantly decreased the expression of colonic and hepatic G-protein coupled receptor (GPR) 41 and 43. Therefore, mAPS supplementation ameliorates hepatic inflammation and lipid accumulation in NAFLD by modulating the gut microbiota and SCFA-GPR signaling pathways. The present study provides new evidence for mAPS as a natural active substance in the treatment of NAFLD.

Ilexsaponin A1 Ameliorates Diet-Induced Nonalcoholic Fatty Liver Disease by Regulating Bile Acid Metabolism in Mice

Bile acid (BA) metabolism is an attractive therapeutic target in nonalcoholic fatty liver disease (NAFLD). We aimed to investigate the effect of ilexsaponin A₁ (IsA), a major bioactive ingredient of Ilex, on high-fat diet (HFD)-induced NAFLD in mice with a focus on BA homeostasis. Male C57BL/6J mice were fed an HFD to induce NAFLD and were treated with IsA (120 mg/kg) for 8 weeks. The results showed that administration of IsA significantly decreased serum total cholesterol (TC), attenuated liver steatosis, and decreased total hepatic BA levels in HFD-induced NAFLD mice. IsA-treated mice showed increased BA synthesis in the alternative pathway by upregulating the gene expression levels of sterol 27-hydroxylase (CYP27A1) and cholesterol 7b-hydroxylase (CYP7B1). IsA treatment accelerated efflux and decreased uptake of BA in liver by increasing hepatic farnesoid X receptor (FXR) and bile salt export pump (BSEP) expression, and reducing Na⁺-taurocholic acid cotransporting polypeptide (NTCP) expression. Alterations in the gut microbiota and increased bile salt hydrolase (BSH) activity might be related to enhanced fecal BA excretion in IsA-treated mice. This study demonstrates that consumption of IsA may prevent HFD-induced NAFLD and exert cholesterol-lowering effects, possibly by regulating the gut microbiota and BA metabolism.

Qingrequzhuo capsule alleviated methionine and choline deficient diet-induced nonalcoholic steatohepatitis in mice through regulating gut microbiota, enhancing gut tight junction and inhibiting the activation of TLR4/NF-κB signaling pathway

Qingrequzhuo capsule (QRQZ), composed of Morus alba L., Coptis chinensis Franch., Anemarrhena asphodeloides Bunge, Alisma plantago-aquatica subsp. orientale (Sam.) Sam., Citrus × aurantium L., Carthamus tinctorius L., Rheum palmatum L., Smilax glabra Roxb., Dioscorea oppositifolia L., Cyathula officinalis K.C.Kuan, has been used to treat nonalcoholic steatohepatitis (NASH) in clinic. However, the mechanism of QRQZ on NASH remains unclear. Recent studies have found that the dysfunction of gut microbiota could impair the gut barrier and induce the activation of TLR4/NF-kB signaling pathway, and further contribute to the inflammatory response in NASH. Modulating the gut microbiota to reduce inflammation could prevent the progression of NASH. In this study, a mouse model of NASH was generated by methionine and choline deficient diet (MCD) and treated with QRQZ. First, we evaluated the therapeutic effects of QRQZ on liver injury and inflammation in the NASH mice. Second, the changes in the gut microbiota diversity and abundance in each group of mice were measured through 16S rRNA sequencing. Finally, the effects of QRQZ on gut mucosal permeability, endotoxemia, and liver TLR4/NF-kB signaling pathway levels were examined. Our results showed that QRQZ significantly reduced the lipid accumulation in liver and the liver injury in NASH mice. In addition, QRQZ treatment decreased the levels of inflammatory cytokines in liver. 16S rRNA sequencing showed that QRQZ affected the diversity of gut microbiota and a f f e c t e d t h e r e l a t i v e a b u n d a n c e s o f D u b o s i e l l a , Lachnospiraceae_NK4A136_group, and Blautiain NASH mice. Besides, QRQZ could increase the expression of tight junction proteins (zonula occludens-1 and occludin) in gut and decrease the lipopolysaccharide (LPS) level in serum. Western blot results also showed that QRQZ treatment decreased the protein expression ofTLR4, MyD88 and the phosphorylation of IkB and NF-kBp65 and qPCR results showed that QRQZ treatment down-regulated the gene expression of interleukin (IL)-1b, IL-6, and tumor necrosis factor (TNF)-a in liver. In conclusion, our study demonstrated that QRQZ could reduce the lipid accumulation and inflammatory response in NASH model mice. The mechanisms of QRQZ on NASH were associated with modulating gut microbiota, thereby inducing the tight junction of gut barrier, reducing the endotoxemia and inhibiting the activation of TLR4/NFkB signaling pathway in liver.