Diosgenin alleviates nonalcoholic steatohepatitis through affecting liver-gut circulation

Natural bioactive compounds reprogram bile acid metabolism in MAFLD: Multi-target mechanisms and therapeutic implications

Metabolic-associated fatty liver disease (MAFLD) has become an increasingly prevalent liver disorder worldwide, being closely associated with obesity, metabolic syndrome, and insulin resistance. Bile acids (BAs), beyond their traditional role in lipid digestion, play a pivotal part in regulating lipid and glucose metabolism as well as inflammatory responses. Recent investigations have recognized BAs as key factors in the onset and progression of MAFLD, mainly via their interactions with nuclear receptors such as the farnesoid X receptor (FXR) and the G protein-coupled bile acid receptor (TGR5). Additionally, active compounds derived from traditional Chinese medicine (TCM) have shown promising potential in the treatment of MAFLD. This study systematically reviews and analyzes the molecular mechanisms and recent progress in the application of TCM active ingredients for MAFLD treatment, with a focus on their regulation of BAs. These active ingredients, including saponins, flavonoids, polysaccharides, and sterols, exert therapeutic effects through diverse mechanisms, such as modulating BA synthesis and mediating receptor-signaling pathways, and are expected to restore metabolic homeostasis.

Diosgenin alleviates lipid accumulation in NAFLD through the pathways of ferroptosis defensive and executive system

The most prevalent liver condition globally is non-alcoholic fatty liver disease (NAFLD), for which no approved therapies currently exist. Diosgenin, an important component in plants from the Leguminosae, Dioscoreaceae, and Solanaceae families, has demonstrated considerable anti-inflammatory and antioxidant effects. Nonetheless, the specific mechanism by which it may act in managing NAFLD remains unclear. Our research aims to explore the effects and molecular mechanisms of DG on NAFLD by utilizing both in vivo and in vitro experimental approaches. To investigate the effect of DG on hepatic steatosis, we used Sprague-Dawley rats induced by a high-fat diet (HFD) and HepG2 cells exposed to free fatty acids. Oil red O staining and hematoxylin-eosin (H&E) staining were used to explore lipid accumulation and hepatic degeneration. ROS staining, SOD, MDA, and Fe2+kits were used to detect the indexes related to oxidative stress in ferroptosis in hepatic tissues and cells. IFSP1 and pcDNA3.1-ACSL4 plasmid were used to knock down Ferroptosis suppressor protein1 (FSP1) and promote the expression of acyl-CoA synthetase long-chain family member 4 (ACSL4) in HepG2 cells. DG improved lipid metabolism disorders and liver damage induced by a high-fat diet in rats with NAFLD. Furthermore, the administration of DG notably decreased oxidative stress levels and liver Fe2+ concentrations in rats. Additionally, in vitro experiments demonstrated that DG treatment markedly attenuated ferroptosis and ROS accumulation in HepG2 cells induced by FFAs. Moreover, overexpression of hepatic ACSL4 expression by pcDNA3.1-ACSL4 plasmid promoted the regulatory effects of DG on LPCAT3 and ALOX15. Our research shows that DG can alleviate NAFLD by regulating the FSP1/COQ10 pathway of the ferroptosis defense system and the ACSL4/LPCAT3/ALOX15 pathway of the ferroptosis execution system. Therefore, DG may serve as a novel inhibitor of ferroptosis for the treatment of NAFLD.

Fluoride induces hepatointestinal damage and vitamin B2 mitigation by regulating IL-17A and Bifidobacterium in ileum

INTRODUCTION

Fluorosis is a global public health disease affecting more than 50 countries and 500 million people. Excessive fluoride damages the liver and intestines, yet the mechanisms and therapeutic approaches remain unclear.

OBJECTIVES

To explore the mechanisms by which fluoride-induced intestinal-hepatic damage and vitamin B2 alleviation.

METHODS

Fluoride and/or vitamin B2-treated IL-17A knockout and wild-type mouse models were established, the morphological and functional changes of liver and gut, total bile acid biosynthesis, metabolism, transport, and regulation of FXR-FGF15 signaling pathways were evaluated, the ileal microbiome was further analyzed by 16S rDNA sequence. Finally, Bifidobacterium supplementation mouse model was designed and re-examined the above indicators.

RESULTS

The results demonstrated that fluoride induced hepatointestinal injury and enterohepatic circulation disorder by altering the synthesis, transporters, and FXR-FGF15 pathway regulation of total bile acid. Importantly, the ileum was found to be the most sensitive and fluoride changed ileal microbiome particularly by reducing abundance of Bifidobacterium. While vitamin B2 supplementation attenuated fluoride-induced enterohepatic circulation dysfunction through IL-17A and ileal microbiome, Bifidobacterium supplementation also reversed fluoride-induced hepatointestinal injury.

CONCLUSION

Fluoride induces morphological and functional impairment of liver and gut tissues, as well as enterohepatic circulation disorder by altering total bile acid (TBA) synthesis, transporters, and FXR-FGF15 signaling regulation. Vitamin B2 attenuated fluoride-induced enterohepatic circulation disorder through IL-17A knockout and ileal microbiome regulation. The ileum was found to be the most sensitive to fluoride, leading to changes in ileal microbiome, particularly the reduction of Bifidobacterium. Furthermore, Bifidobacterium supplementation reversed fluoride-induced hepatointestinal injury. This study not only elucidates a novel mechanism by which fluoride causes hepatointestinal toxicity, but also provides a new physiological function of vitamin B2, which will be useful in the therapy of fluorosis and other hepatoenterological diseases.

Sophocarpine suppresses MAPK-mediated inflammation by restoring gut microbiota in colorectal cancer

BACKGROUND

Colorectal cancer (CRC), as one of the most common cancers globally, poses a significant challenge to public health due to its high incidence and mortality rates. This underscores the need for continuous exploration of new therapeutic targets and effective drugs. Sophocarpine (SC), a natural compound derived from traditional Chinese medicine, holds considerable therapeutic potential in the treatment of CRC, however, the relevant mechanisms remains unclear.

PURPOSE

This study aims to explore the anti-tumor effects of SC against CRC by modulating gut microbiota, and uncover potential mechanisms linking SC's therapeutic effects to gut microbiota regulation by analyzing the impact of SC on microbiota composition and CRC progression.

MATERIAL

This study explores the impact of SC on the gut microbiota in CRC by constructing subcutaneous xenograft tumors of CRC and integrating 16S rRNA sequencing and RNA transcriptomic sequencing. The fecal microbiota transplantation (FMT) mouse model was used to validate the biological function of SC in correcting gut microbiota dysbiosis to treat CRC. Subsequently, we conducted in vitro studies on the molecular mechanisms by which SC regulates the gut microbiota as an effective hallmark of CRC treatment, using lipopolysaccharide (LPS) to simulate an inflammatory gut microbiota environment and P38 MAPK knockdown cell line.

RESULTS

SC significantly inhibited CRC cell proliferation with IC50 values of 2.547±0.256 μM for HCT116 and 2.851±0.332 μM for LoVo cells. In vivo experiments demonstrated that SC effectively suppressed tumor growth in xenograft models. 16S rRNA sequencing revealed that SC modulated gut microbiota composition, particularly affecting Bacteroides and Alistipes populations. SC significantly reduced the levels of inflammatory factors and inhibited the MAPK signaling pathway, as evidenced by decreased p-JNK, p-p38 MAPK, and p-NF-κB p65 expression.

CONCLUSIONS

Current clinical practice still lacks effective therapeutic agents targeting CRC through gut microbiota modulation. This study presents the first evidence that SC, a natural compound, exhibits dual-action therapeutic efficacy against CRC progression by simultaneously modulating gut microbial composition and suppressing MAPK pathway-mediated inflammatory responses. These findings highlight SC's novel therapeutic potential as a promising microbiota-regulating candidate for CRC intervention, offering an innovative approach that bridges microbial ecology with cancer signaling pathways.

Salidroside attenuates NASH through regulating bile acid-FXR/TGR5 signaling pathway via targeting gut microbiota

Nonalcoholic steatohepatitis (NASH) is a significant threat to human health. Our previous study revealed that salidroside attenuated NASH and regulated the gut microbiota. However, whether the therapeutic effect of salidroside depends on gut microbiota remains to be determined. Therefore, we conducted further experiments to elucidate the essential functions of gut microbiota-associated metabolic pathways in the anti-NASH effects of salidroside. Our results showed that salidroside effectively alleviated lipid accumulation and inflammatory injury in NASH mice. 16S rRNA sequencing revealed that salidroside increased the abundance of Bacteroides. Mice receiving fecal microbiota transplantation (FMT) from salidroside-treated also presented less hepatic steatosis and higher abundance of Bacteroides. Antibiotics eliminated the effects of salidroside on hepatic steatosis and the gut microbiota. Mechanistically, salidroside and FMT from salidroside-treated altered the bile acid (BA) profile by decreasing the levels of conjugated BAs and tauro-α/β-muricholic acid and activated downstream farnesoid X receptor (FXR) and Takeda G protein-coupled receptor 5 (TGR5). Furthermore, we found that inhibitors of bile salt hydrolase (BSH) and FXR/TGR5 abolished the effects of salidroside and reduced downstream carnitine palmitoyltransferase 1α and lipoprotein lipase expression. These data demonstrate that salidroside attenuated NASH via gut microbiota-BA-FXR/TGR5 signaling pathway and reveal the underlying mechanism of salidroside on NASH.

Targeting Metabolism: Innovative Therapies for MASLD Unveiled

The recent introduction of the term metabolic-dysfunction-associated steatotic liver disease (MASLD) has highlighted the critical role of metabolism in the disease's pathophysiology. This innovative nomenclature signifies a shift from the previous designation of non-alcoholic fatty liver disease (NAFLD), emphasizing the condition's progressive nature. Simultaneously, MASLD has become one of the most prevalent liver diseases worldwide, highlighting the urgent need for research to elucidate its etiology and develop effective treatment strategies. This review examines and delineates the revised definition of MASLD, exploring its epidemiology and the pathological changes occurring at various stages of the disease. Additionally, it identifies metabolically relevant targets within MASLD and provides a summary of the latest metabolically targeted drugs under development, including those in clinical and some preclinical stages. The review finishes with a look ahead to the future of targeted therapy for MASLD, with the goal of summarizing and providing fresh ideas and insights.

A study of correlation of the dietary index for gut microbiota with non-alcoholic fatty liver disease based on 2007-2018 National Health and Nutrition Examination Survey

Objective

To explore the correlation of dietary index for gut microbiota (DI-GM) with non-alcoholic fatty liver disease (NAFLD).

Methods

Data of 6,711 participants were extracted from the National Health and Nutrition Examination Survey (NHANES) during 2007-2018. A weighted logistic regression analysis was employed for assessment of the correlation of DI-GM with NAFLD, and a restricted cubic spline (RCS) analysis was implemented to examine potential non-linear associations. Subgroup analyses were conducted to identify particularly susceptible groups. Additionally, the synergistic effects of different DI-GM components on NAFLD risk was assessed by weighted quantile sum (WQS) regression.

Results

The DI-GM exhibited statistically significant correlation with NAFLD [OR (95%CI):0.91 (0.85, 0.98), p = 0.015]. The results of the RCS analysis indicated a linear correlation of DI-GM and NAFLD (p = 0.810 for non-linearity). Further stratified analyses indicated that the negative correlation of DI-GM with NAFLD were significant and consistent for all subgroups. The results of WQS regression revealed that soybean (27%), refined grains (17%), coffee (16%), and red meat (9%) had the highest contribution weights to NAFLD.

Conclusion

As an important tool for assessment of the influences of diet on gut microbiota, DI-GM is negatively correlated with NAFLD risk factors. Soybean, refined grains, coffee, and red meat are key factors influencing NAFLD. The direct correlation of DI-GM with NAFLD shall be explored and the effectiveness of prevention and treatment of NAFLD shall be evaluated by improving DI-GM scores via dietary interventions.

Gut Microbiota and Its Metabolite Taurine-β-Muricholic Acid Contribute to Antimony- and/or Copper-Induced Liver Inflammation

Antimony and copper can contaminate vegetables and enter the human body through the digestive tract, inducing severe and extensive biotoxicity. However, the role of bile acids (BAs) in the pathogenesis of liver inflammation by antimony or copper has not been elucidated. Our results indicated that antimony and/or copper induced liver inflammation, causing the disruption of gut microbiota, with the down-regulation of probiotics and up-regulation of harmful bacteria closely correlated to liver inflammation. Targeted metabolomics of BAs showed that antimony and/or copper significantly up-regulated the levels of taurine-β-muricholic acid (T-β-MCA) in serum and liver, which was due to the reduction of Lactobacillus spp. A farnesoid X receptor (FXR) antagonist, T-β-MCA inhibited the FXR-SHP pathway in liver and FXR-FGF15 pathway in ileum, thereby promoting the transcription of cholesterol 7-alpha hydroxylase (CYP7A1) and increasing total bile acid concentrations, ultimately leading to liver inflammation. These findings provide new insights into the underlying mechanisms of antimony- and/or copper-induced liver inflammation.

Network pharmacology-based investigation of the pharmacological mechanisms of diosgenin in nonalcoholic steatohepatitis

The prevalence of nonalcoholic steatohepatitis (NASH) is rising annually, posing health and economic challenges, with limited treatments available. Diosgenin, a natural steroidal compound found in various plants, holds potential as a therapeutic candidate. Recent studies have confirmed diosgenin's anti-inflammatory and metabolism-modulating properties. However, its therapeutic effects on NASH and the underlying mechanisms are still unclear. This study aims to explore diosgenin's protective effects and pharmacological mechanisms against NASH using network pharmacology, molecular docking, and experimental validation. We gathered potential targets of diosgenin and NASH from various databases to generate protein-protein interaction (PPI) networks. GO and KEGG pathway enrichment analyses identified key targets and mechanisms. Molecular docking confirmed the binding capacity between diosgenin and core target proteins. Additionally, a NASH cell model was developed to validate the pharmacological effects of diosgenin. Our investigation identified nine key targets (ALB, AKT1, TP53, VEGFA, MAPK3, EGFR, STAT3, CASP3, IGF1) that interact with diosgenin. Molecular docking indicated potential bindings interactions, while enrichment analyses revealed that diosgenin may enhance fatty acid metabolism via the PI3K-Akt pathway. Cellular experiments confirmed that diosgenin activates this pathway, reduces SCD1 expression, and decreases triglyceride and IL-6 levels. Our study elucidates that diosgenin may ameliorate triglyceride deposition and inflammation through the PI3K-Akt pathway.

Folic acid alleviates the negative effects of dexamethasone induced stress on production performance in Hyline Brown laying hens

Multiple stressors are believed to deteriorate production performance and cause substantial economic losses in commercial poultry farming. Folic acid (FA) is an antioxidant compound that can improve oocyte function and regulate gut microbiota composition. The current study was conducted to investigate the role of FA in alleviating stress and improving production performance. Sixty Hyline Brown laying hens at 21 weeks of age were randomly divided into three groups, with 10 replicates in each group and each replicate containing two chickens. Each group received basic diet and saline injection (Con group), basic diet with dexamethasone (DXM) injection (DXM group), or basic diet supplemented with FA (13 mg/kg in the premix) with DXM injection (FA group). The feeding trial lasted five weeks. Birds in the DXM and FA groups receiving subcutaneous DXM injections at a dosage of 4.50 mg/kg per day during the first seven days of the trial. Results showed that the levels of corticosterone, triglyceride, total cholesterol, and malondialdehyde in serum were significantly increased in the DXM group (P < 0.05), while the concentrations of FA and 5-methyltetrahydrofolate were decreased in the DXM group (P < 0.05). Laying hens in the DXM group had lower laying rates and egg quality, including egg weight, eggshell thickness, eggshell strength, albumen height, and Haugh units (P < 0.05). Conversely, FA alleviated these negative impacts. Through transcriptome analysis, a total of 247 and 151 differentially expressed genes were identified among the three groups, and 32 overlapped genes were further identified. Moreover, 44 and 59 differential metabolites were influenced by DXM and FA, respectively. Kyoto Encyclopedia of Genes and Genomes enrichment from the transcriptome and metabolomics showed that the reduced production performance may be due to the disturbance of oocyte production, calcium metabolism, and oxidative stress. Analysis of 16S rRNA gene amplicon sequences revealed the differential microbial composition and potential functional changes among the different groups. LEfSe analysis showed that Mucispirillum and Nautella were the predominant bacteria in the DXM group, while Clostridium was the predominant bacteria in the FA group. Functional prediction demonstrated that stressors enhanced fatty acid biosynthesis, while betaine biosynthesis and retinol metabolism were elevated in the FA group. Dietary FA reversed the elevated levels of bile acids (BA), including cholic acid, taurodeoxycholic acid, and taurochenodeoxycholic acid (P < 0.05). The DXM group showed an overall decrease in short-chain fatty acids (SCFA), but FA restored the concentrations of acetic acid, propionic acid, and isobutyric acid (P < 0.05). In conclusion, this study reveals that dietary FA can alleviate the degradation of production performance caused by stress through improving circulating antioxidant capacity, maintaining intestinal microbiota homeostasis, and regulating SCFA and BA biosynthesis. Thus, highlighting the prominent role of gut microbe-host interactions in alleviating multi-stresses.

Drug Advances in NAFLD: Individual and Combination Treatment Strategies of Natural Products and Small-Synthetic-Molecule Drugs

Non-alcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease and is closely associated with metabolic diseases such as obesity, type 2 diabetes mellitus (T2DM), and metabolic syndrome. However, effective treatment strategies for NAFLD are still lacking. In recent years, progress has been made in understanding the pathogenesis of NAFLD, identifying multiple therapeutic targets and providing new directions for drug development. This review summarizes the recent advances in the treatment of NAFLD, focusing on the mechanisms of action of natural products, small-synthetic-molecule drugs, and combination therapy strategies. This review aims to provide new insights and strategies in treating NAFLD.

Diosgenin attenuates nonalcoholic fatty liver disease through mTOR-mediated inhibition of lipid accumulation and inflammation

Excessive hepatic lipid accumulation and inflammatory injury are significant pathological manifestations of nonalcoholic fatty liver disease (NAFLD). Our previous research discovered that diosgenin, a natural steroidal saponin derived from Chinese herbs, can reduce hepatic lipid accumulation and steatosis; however, the exact mechanism remains unclear. This study aimed to investigate the protective mechanisms of diosgenin against NAFLD. We utilized network pharmacology and molecular docking approaches to identify the pathways through which diosgenin improves NAFLD. In high-fat diet (HFD)-fed rats, we measured biochemical markers in the serum and liver. Liver histopathology was assessed using HE and oil-red O staining. In free fatty acids (FFAs)-induced HepG2 cells, we employed the cell transfection overexpression method to verify the regulatory relationship of the identified pathways. The mechanisms in vitro and in vivo were examined using quantitative polymerase chain reaction and Western blot analyses. Bioinformatics analysis indicated that the mTOR-FASN/HIF-1α/RELA/VEGFA pathway may be the target pathway for diosgenin in alleviating NAFLD. Diosgenin inhibited hepatic lipid accumulation and pro-inflammatory cytokines in HFD-fed rats, and reduced intracellular lipid accumulation as well as TG, TC, IL-1β, and TNF-α levels in FFAs-induced HepG2 cells. Mechanistically, diosgenin downregulated the expression of p-mTOR, FASN, HIF-1α, RELA, and VEGFA, which are associated with lipid synthesis and inflammation. Overexpression of mTOR abolished the beneficial effects of diosgenin on lipid reduction and inflammation, as well as its inhibitory effects on the expression of FASN, HIF-1α, RELA, and VEGFA. In conclusion, diosgenin alleviates NAFLD through mTOR-mediated inhibition of lipid accumulation and inflammation.

Multidimensional Uses of Bitter Melon (Momordica charantia L.) Considering the Important Functions of its Chemical Components

Bitter melon (Momordica charantia L.) is a member of the Cucurbitaceae, which is also known as bitter squash, bitter gourd, karela, Goya melon and balsam pear. It is a rich source of different vitamins, potassium, zinc and other nutrients. The main pharmaceutical benefits of bitter melon are "antiinflammatory", "antioxidant activity", "antimicrobial characteristic", "anticancer activity", and "antihelmintic activity", "antidiabetic effects", "antiinflammation activity" and "treat skin conditions". Its fruit is the main part of the plant which has been used for medicinal and food purposes. The primary metabolites in bitter gourd are common sugars, chlorophyll and proteins while secondary metabolites are carotenoids, alkaloids, phenolics, curcubitane triterpenoids, saponins, etc. The present review aims to study and survey on the nearly up-to-date results and findings regarding the pharmaceutical advantages and health benefits of bitter melon in an organic life.

Gut Microbiota as Mediator and Moderator Between Hepatitis B Virus and Hepatocellular Carcinoma: A Prospective Study

BACKGROUND

The impact of gut microbiome on hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) is unclear. We aimed to evaluate the potential correlation between gut microbiome and HBV-related HCC and introduced novel machine learning (ML) signatures based on gut microbe to predict the risk of HCC.

MATERIALS AND METHODS

A total of 640 patients with chronic liver diseases or HCC were prospectively recruited between 2019 and 2022. Fecal samples were collected and subjected to 16S rRNA gene sequencing. Univariate and multivariate logistic regression was applied to identify risk characteristics. Several ML methods were employed to construct gut microbe-based models and the predictive performance was evaluated.

RESULTS

A total of 571 patients were involved in the study, including 374 patients with HCC and 197 patients with chronic liver diseases. After the propensity score matching method, 147 pairs of participants were enrolled in the analysis. Bacteroidia and Bacteroidales were demonstrated to exert mediating effects between HBV and HCC, and the moderating effects varied across Bacilli, Lactobacillales, Erysipelotrichaceae, Actinomyces, and Roseburia. HBV, alpha-fetoprotein, alanine transaminase, triglyceride, and Child-Pugh were identified as independent risk factors for HCC occurrence. Seven ML-based HBV-gut microbe models were established to predict HCC, with AUCs ranging from 0.821 to 0.898 in the training set and 0.813-0.885 in the validation set. Furthermore, the merged clinical-HBV-gut microbe models exhibited a comparable performance to HBV-gut microbe models.

CONCLUSIONS

Gut microbes are important factors between HBV and HCC through its potential mediating and moderating effects, which can be used as valuable biomarkers for the pathogenesis of HBV-related HCC.

Pueraria Extract Ameliorates Alcoholic Liver Disease via the Liver-Gut-Brain Axis: Focus on Restoring the Intestinal Barrier and Inhibiting Alcohol Metabolism

Alcoholic liver disease (ALD) is one of the causes of hepatocellular carcinoma, accompanied by intestinal leakage and microbial changes. Pueraria has protective effects on liver injury. The aim of this study was to investigate the mechanism of pueraria in the treatment of ALD. UPLC-Q/TOF-MS was used to analyze the composition of the pueraria extract (PUE). Acute and chronic ALD models were established to evaluate the antialcoholic and hepatoprotective effects of PUE. As a result, PUE treatment reduced the serum levels of ALT, AST, TC, and TG and inflammatory factors and alleviated liver inflammation and drunk state. PUE decreased the gene expression of ADH1 and the serum level of acetaldehyde (ACH) to inhibit the generation of ACH from ethanol metabolism, increased the gene level of ALDH2 to accelerate the decomposition of ACH, and thereby alleviated liver inflammation and intestinal barrier damage. Meanwhile, 16 S rDNA revealed that PUE altered the microbiota composition, reduced the amount of Proteobacteria and Desulfobacterota, and thus inhibited the generation of lipopolysaccharide and its downstream-like TLR4/MyD88/NF-κB pathway. PUE also increased the abundance of Bacteroides, Ruminococcus, and Prevotella and producted short-chain fatty acids to protect the intestinal wall. Treatment with fecal microbiota transplantation further confirmed that PUE gut microbiota dependently alleviated ALD. Therefore, PUE regulated gut microbiota and inhibited ethanol metabolism to alleviate ALD through the liver-gut-brain axis. It has good prospects in the future.

Litchi Procyanidins Ameliorate DSS-Induced Colitis through Gut Microbiota-Dependent Regulation of Treg/Th17 Balance

Ulcerative colitis (UC) is a common chronic, relapsing inflammatory bowel condition. Procyanidins (PC) are known for their antiangiogenic, anti-inflammatory, antioxidant, and antimetastatic properties. However, there is comparatively limited information on how PC interacts with UC. In this study, 5 mg/10 mL/kg body weight of PC was administered to mice with dextran sulfate sodium (DSS)-induced colitis mice. PC treatment prolonged the survival period of mice, ameliorated UC symptoms, reduced damage to the intestinal mucosal barrier, and increased the protein expression of ZO-1 and occludin in the DSS-treated mice. Importantly, PC treatment significantly reduced gene expression related to Th17 cell differentiation, including STAT3, SMAD3, TGF-β, and JAK1. The results of the flow cytometry analysis indicated significant increase in the number of Treg cells and a concomitant decrease in the proportion of Th17 cells in the colon following PC treatment. Additionally, PC increased the abundance of gut microbiota such as Bacteroidota, Oscillospiraceae, Muribaculaceae, and Desulfovibrionaceae, as well as the concentrations of acetate acid, propionate acid, and butyrate acid in the feces. PC also activated short-chain fatty acid receptors, such as G-protein coupled receptor 43 in the colon, which promoted the proliferation of Treg cells. The depletion of gut microbiota and subsequent transplantation of fecal microbiota demonstrated that PC's effects on gut microbiota were effective in improving UC and restoring intestinal Th17/Treg homeostasis in a microbiota-dependent manner. This suggests that PC could be a promising functional food for the prevention and treatment of UC in the future.

Yellow tea polysaccharides protect against non-alcoholic fatty liver disease via regulation of gut microbiota and bile acid metabolism in mice

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a major clinical and global public health issue, with no specific pharmacological treatment available. Currently, there is a lack of approved drugs for the clinical treatment of NAFLD. Large-leaf yellow tea polysaccharides (YTP) is a natural biomacromolecule with excellent prebiotic properties and significant therapeutic effects on multiple metabolic diseases. However, the specific mechanisms by which YTP regulates NAFLD remain unclear.

PURPOSE

This study aims to explore the prebiotic effects of YTP and the potential mechanisms by which it inhibits hepatic cholesterol accumulation in NAFLD mice.

METHODS

The effects of YTP on lipid accumulation were evaluated in NAFLD mice through obesity trait analysis and bile acids (BAs) metabolism assessment. Additionally, fecal microbiota transplantation (FMT) was performed, and high-throughput sequencing was employed to investigate the mechanisms underlying YTP's regulatory effects on gut microbiota and BA metabolism.

RESULTS

Our study demonstrated that YTP altered the constitution of colonic BA, particularly increasing the levels of conjugated BA and non-12OH BA, which suppressed ileum FXR receptors and hepatic BA reabsorption, facilitated BA synthesis, and fecal BA excretion. The modifications were characterized by a decrease in the levels of FXR, FGF15, FGFR4, and ASBT proteins, and an increase in the levels of Cyp7a1 and Cyp27a1 proteins. YTP might affect enterohepatic circulation and by the activated the hepatic FXR-SHP pathway. Meanwhile, YTP reshaped the intestinal microbiome structure by decreasing BSH-producing genera and increasing taurine metabolism genera. The correlation analysis implied that Muribaculaceae, Pseudomonas, acterium_coprostanoligenes_group, Clostridiales, Lachnospiraceae_NK4A136_group, Delftia, Dubosiella, and Romboutsia were strongly correlated with specific BA monomers.

CONCLUSIONS

YTP modulates bile salt hydrolase-related microbial genera to activate alternative bile acid synthesis pathways, thereby inhibiting NAFLD progression. These results suggest that YTP may serve as a potential probiotic formulation, offering a feasible dietary intervention for NAFLD.

Diosgenin attenuates metabolic-associated fatty liver disease through the hepatic NLRP3 inflammasome-dependent signaling pathway

Metabolic-associated fatty liver disease (MAFLD) is one of the most common liver diseases worldwide; however, its pathogenesis and treatment methods have not been perfected. NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) is a promising therapeutic target for MAFLD. Diosgenin (DG) is a natural compound that was identified in a traditional Chinese herbal medicine, which has pharmacological effects, such as anti-inflammatory, antioxidant, hepatoprotective, and hypolipidemic activities. In this study, we examined the effects and molecular mechanisms of DG on MAFLD in vitro and in vivo. We established a rat model by administering a high-fat diet (HFD). We also generated an in vitro MAFLD model by treating HepG2 cells with free fatty acids (FFAs). The results indicated that DG attenuated lipid accumulation and liver injury in both in vitro and in vivo models. DG downregulated the expression of NLRP3, apoptosis-associated speckle-like protein (ASC), cysteinyl aspartate specific proteinase-1 (caspase-1), gasdermin D (GSDMD), GSDMD-n, and interleukin-1β (IL-1β). In addition, we silenced and overexpressed NLRP3 in vitro to determine the effects of DG on antiMAFLD. Silencing NLRP3 enhanced the effect of DG on the treatment of MAFLD, whereas NLRP3 overexpression reversed its beneficial effects. Taken together, the results show that DG has a favorable effect on attenuating MAFLD through the hepatic NLRP3 inflammasome-dependent signaling pathway. DG represents a natural NLRP3 inhibitor for the MAFLD treatment.

The role of botanical triterpenoids and steroids in bile acid metabolism, transport, and signaling: Pharmacological and toxicological implications

Bile acids (BAs) are synthesized by the host liver from cholesterol and are delivered to the intestine, where they undergo further metabolism by gut microbes and circulate between the liver and intestines through various transporters. They serve to emulsify dietary lipids and act as signaling molecules, regulating the host's metabolism and immune homeostasis through specific receptors. Therefore, disruptions in BA metabolism, transport, and signaling are closely associated with cholestasis, metabolic disorders, autoimmune diseases, and others. Botanical triterpenoids and steroids share structural similarities with BAs, and they have been found to modulate BA metabolism, transport, and signaling, potentially exerting pharmacological or toxicological effects. Here, we have updated the research progress on BA, with a particular emphasis on new-found microbial BAs. Additionally, the latest advancements in targeting BA metabolism and signaling for disease treatment are highlighted. Subsequently, the roles of botanical triterpenoids in BA metabolism, transport, and signaling are examined, analyzing their potential pharmacological, toxicological, or drug interaction effects through these mechanisms. Finally, a research paradigm is proposed that utilizes the gut microbiota as a link to interpret the role of these important natural products in BA signaling.

Formosanin C inhibits pulmonary metastasis by targeting stearyl CoA desaturase-1

BACKGROUND

Cisplatin (DDP) as the first-line drug has been used in cancer therapy. However, side effects and drug resistance are the challenges of DDP. Disordered lipid metabolism is related to DDP resistance.

STUDY DESIGN

In this study, formosanin C (FC) as the main compound of Rhizoma Paridis saponins (RPS) inhibits pulmonary metastasis by targeting stearyl CoA desaturase-1.

METHODS AND RESULTS

RPS prolonged the survival period of mice, reduced pulmonary metastases and alleviated colon toxicity caused by DDP. FC as the main compound of RPS enhanced the anti-tumor and anti-metastatic effects of DDP. FC decreased the mRNA level of SCD1 and the content of lipid droplets (LDs) in lung cancer cells. Molecular dynamics and isothermal titration calorimetry verified the binding stability and spontaneously between FC and SCD1. SiSCD1 reduced the content of LDs in cell lines and increased mitochondria (mtROS), which was consistent with the results of FC treatment. The combination group decreased DNA repair associated protein as well as DDP resistance markers such as ERCC1 and 53bp1, and increased DNA damage marker like γH2AX, which indirectly confirmed the occurrence of mtROS. In addition, FC combination with DDP also affected epithelial-mesenchymal transition-related protein like VIM and CDH1 in vivo experiments, and thereby inhibited pulmonary metastasis.

CONCLUSION

Our research indicated that the FC as the main compound of RPS targeted the CY2 domain of SCD1, inhibited lipid metabolism in mice, and thereby suppressed cancer metastases. This provided support for use of FC to treat cancer based on lipid metabolism pathway.

Effects of Saponins on Lipid Metabolism: The Gut-Liver Axis Plays a Key Role

Unhealthy lifestyles (high-fat diet, smoking, alcohol consumption, too little exercise, etc.) in the current society are prone to cause lipid metabolism disorders affecting the health of the organism and inducing the occurrence of diseases. Saponins, as biologically active substances present in plants, have lipid-lowering, inflammation-reducing, and anti-atherosclerotic effects. Saponins are thought to be involved in the regulation of lipid metabolism in the body; it suppresses the appetite and, thus, reduces energy intake by modulating pro-opiomelanocortin/Cocaine amphetamine regulated transcript (POMC/CART) neurons and neuropeptide Y/agouti-related peptide (NPY/AGRP) neurons in the hypothalamus, the appetite control center. Saponins directly activate the AMP-activated protein kinase (AMPK) signaling pathway and related transcriptional regulators such as peroxisome-proliferator-activated-receptors (PPAR), CCAAT/enhancer-binding proteins (C/EBP), and sterol-regulatory element binding proteins (SREBP) increase fatty acid oxidation and inhibit lipid synthesis. It also modulates gut-liver interactions to improve lipid metabolism by regulating gut microbes and their metabolites and derivatives-short-chain fatty acids (SCFAs), bile acids (BAs), trimethylamine (TMA), lipopolysaccharide (LPS), et al. This paper reviews the positive effects of different saponins on lipid metabolism disorders, suggesting that the gut-liver axis plays a crucial role in improving lipid metabolism processes and may be used as a therapeutic target to provide new strategies for treating lipid metabolism disorders.

Construction of nanoparticles from blueberry anthocyanins-lecithin/gum Arabic improves lipid droplet accumulation and gut microbiota disturbance in HFD-induced obese mice

The digestive instability of anthocyanins (ACNs) limits their application in food nutrition, especially precision nutrition. Blueberry ACNs-loaded nanoparticles (Lipo/GA-ACNs NPs) were prepared using gum arabic (GA) as the delivery carrier and liposomal vesicles (Lipo) prepared from soy lecithin as the targeting scaffold. The average particle size of the NPs was 99.4 nm, and the polydispersion index (PDI) was 0.46. The results showed that the presence of the Lipo-GA matrix enhanced the NPs' in vitro stability and antioxidant activity. In addition, the in vitro biocompatibility, uptake ability, lipid-lowering activity, and free-radical scavenging ability were improved to a certain extent. In a high-fat diet (HFD)-induced obese mouse model, oral administration of ACNs-LNP (LNP, liver-targeted nanoparticle) showed better effects on body weight, liver injury, and lipid droplet accumulation in the liver than ACNs. In addition, ACNs-LNP also played a role in regulating HFD-induced gut microbiota imbalance. These results provide a promising ACNs delivery strategy with the potential to be developed into a functional food that targets the liver to prevent fatty liver.

Therapeutic Potential of Diosgenin in Amelioration of Carbon Tetrachloride-Induced Murine Liver Injury

Diosgenin is a sapogenin with antidiabetic, antioxidant, and anti-inflammatory properties. The current study investigated whether diosgenin could ameliorate carbon tetrachloride (CCL4)-induced liver injury. To cause liver injury, CCL4 was injected intraperitoneally twice a week for 8 weeks. Daily oral administration of diosgenin at doses of 20, 40, and 80 mg/kg was started one day before CCL4 injection and continued for 8 weeks. Finally, serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and also albumin were assessed. Catalase and superoxide dismutase (SOD) activities in addition to glutathione (GSH) and malondialdehyde (MDA) levels were also quantified in the liver homogenate and routine histological evaluation was also conducted. Elevated serum levels of liver enzymes and decreased serum level of albumin caused by CCL4 were significantly restored following diosgenin administration at doses of 40 and 80 mg/kg. Long-term administration of CCL4 increased inflammatory and apoptotic factors such as IL-1β, caspase 3, TNF-α, and IL-6 and decreased SOD and catalase activities as well as GSH level in liver homogenates; while MDA level was increased. Treatment with diosgenin increased SOD and catalase activities and GSH levels in the liver of injured animals. In addition, liver MDA, IL-1β, caspase 3, TNF-α, and IL-6 level or activity decreased by diosgenin treatment. Additionally, diosgenin aptly prevented aberrant liver histological changes. According to obtained results, diosgenin can dose-dependently diminish CCl4-induced liver functional deficits and histological changes in a dose-dependent manner, possibly due to its antioxidant and anti-inflammation properties, and its beneficial effect is comparable to known hepatoprotective agent silymarin.

Diosgenin as a substitute for cholesterol alleviates NAFLD by affecting CYP7A1 and NPC1L1-related pathway

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) rapidly becomes the leading cause of end-stage liver disease or liver transplantation. Nowadays, there has no approved drug for NAFLD treatment. Diosgenin as the structural analogue of cholesterol attenuates hypercholesterolemia by inhibiting cholesterol metabolism, which is an important pathogenesis in NAFLD progression. However, there has been no few report concerning its effects on NAFLD so far.

METHODS

Using a high-fat diet & 10% fructose-feeding mice, we evaluated the anti-NAFLD effects of diosgenin. Transcriptome sequencing, LC/MS analysis, molecular docking simulation, molecular dynamics simulations and Luci fluorescent reporter gene analysis were used to evaluate pathways related to cholesterol metabolism.

RESULTS

Diosgenin treatment ameliorated hepatic dysfunction and inhibited NAFLD formation including lipid accumulation, inflammation aggregation and fibrosis formation through regulating cholesterol metabolism. For the first time, diosgenin was structurally similar to cholesterol, down-regulated expression of CYP7A1 and regulated cholesterol metabolism in the liver (p < 0.01) and further affecting bile acids like CDCA, CA and TCA in the liver and feces. Besides, diosgenin decreased expression of NPC1L1 and suppressed cholesterol transport (p < 0.05). Molecular docking and molecular dynamics further proved that diosgenin was more strongly bound to CYP7A1. Luci fluorescent reporter gene analysis revealed that diosgenin concentration-dependently inhibited the enzymes activity of CYP7A1.

CONCLUSION

Our findings demonstrated that diosgenin was identified as a specific regulator of cholesterol metabolism, which pave way for the design of novel clinical therapeutic strategies.