Role of gut-liver axis and glucagon-like peptide-1 receptor agonists in the treatment of metabolic dysfunction-associated fatty liver disease

Integrating 16S rDNA sequencing analysis and targeted metabolomics to explore the mechanism of Xiexin Tang in treating atherosclerosis mice induced by high-fat diet

Xiexin Tang (XXT) is a classic Chinese medicine formula that can be used to treat Atherosclerosis (AS). This study aimed to investigate the mechanism by which XXT regulated AS lipid levels. Firstly, the mixture components of XXT were analyzed by High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Then, the AS model based on Apolipoprotein E knockout (ApoE-/-) mice was established. Cytokines related to lipid metabolism and bile acid metabolism were detected by Quantitative Real-time PCR (qRT-PCR). 16S rDNA gene sequencing was performed to analyze differential bacterial populations, and the mechanism of XXT regulation of bile acids affecting lipid metabolism was further explored by targeted metabolomics. Further, antibiotic-treated mice were used to investigate the role of gut microbiota in the anti-AS effect of XXT. The results showed that XXT attenuated the lipid levels and reversed the abnormal elevation of cytokines, such as hepatic lipid metabolism and inflammatory reaction in AS mice. XXT also repaired the gut barrier damage and reversed gut microbiota disorders in AS mice. Furthermore, the metabolic levels of bile acids were reshaped by XXT. Whereas, in the absence of gut microbiota, XXT failed to attenuate lipid levels and inhibit the expression of cytokines related to inflammation and bile acid metabolism in AS mice and failed to play a role in ultimately treating AS. In conclusion, XXT could effectively inhibit the inflammatory reaction and lipid accumulation in AS mice, and this effect was closely related to its remodeling of gut microbiota to regulate bile acid metabolism.

Unlocking the gut-liver axis: microbial contributions to the pathogenesis of metabolic-associated fatty liver disease

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a complex metabolic disorder characterized by hepatic lipid accumulation and subsequent inflammation. This condition is closely linked to metabolic syndrome and obesity, with its prevalence rising due to sedentary lifestyles and high-calorie diets. The pathogenesis of MAFLD involves multiple factors, including insulin resistance, lipotoxicity, oxidative stress, and inflammatory responses. The gut microbiota plays a crucial role in MAFLD development, with dysbiosis contributing to liver inflammation through various mechanisms, such as enhanced intestinal permeability and the translocation of bacterial products like lipopolysaccharide (LPS). Microbial metabolites, including short-chain fatty acids (SCFAs) and bile acids, influence hepatic function and immune responses, with potential implications for disease progression. Specific gut microbiome signatures have been identified in MAFLD patients, offering potential diagnostic and therapeutic targets. Moreover, gut-derived toxins, such as endotoxins, lipopolysaccharides, trimethylamine-N-oxide and bacterial metabolites, significantly influence liver damage and inflammation, highlighting the complex interplay between the gut microbiome and hepatic health. This review comprehensively examines the complex interplay between the gut microbiota and MAFLD, focusing on underlying pathogenic mechanisms, potential biomarkers, and emerging microbiome-targeted therapeutic strategies for disease management.

Glucagon-Like Peptide-1 Receptor Agonists and Liver Outcomes in Patients With MASLD and Type 2 Diabetes

BACKGROUND AND AIMS

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and sodium-glucose cotransporter-2 inhibitors (SGLT2is) have demonstrated long-term liver benefits in patients with metabolic dysfunction-associated steatotic liver disease (MASLD) and type 2 diabetes (T2D). However, no direct comparison between these therapies has been conducted. This study aimed to compare major adverse liver outcomes (MALOs) between GLP-1 RAs and SGLT2is in patients with MASLD and T2D.

METHODS

Using the TriNetX Research Network, a multinational and multi-institutional database, we identified adults with MASLD and T2D who received their first prescription for either a GLP-1 RA or an SGLT2i between January 2010 and June 2023. We conducted a propensity score-matched (PSM) cohort study comparing new users of GLP-1 RAs and SGLT2is. The primary outcome was the risk of MALOs, a composite endpoint consisting of decompensated cirrhosis events, hepatocellular carcinoma, and liver transplantation. Secondary outcomes included all-cause mortality and individual components of the primary outcome.

RESULTS

This study included 15,176 pairs of patients treated with either a GLP-1 RA or a SGLT2i. The adjusted hazard ratio (HR) for MALO associated with GLP-1 RAs relative to SGLT2is was 0.84 (95% confidence interval [CI]: 0.73-0.97; incidence rate: 88.9 versus 105.3 events per 10,000 person-years), primarily driven by reduction in decompensated cirrhosis events (adjusted HR: 0.83, 95% CI: 0.71-0.96). GLP-1 RAs were associated with lower all-cause mortality (adjusted HR: 0.84, 95% CI: 0.75-0.94).

CONCLUSION

GLP-1 RAs are associated with better long-term liver outcomes compared to SGLT2is in patients with MASLD and T2D.

Advances in intrahepatic and extrahepatic vascular dysregulations in cirrhotic portal hypertension

Cirrhotic portal hypertension, the most prevalent and clinically significant complication of liver cirrhosis, manifests as elevated portal venous pressure and is associated with severe complications. Although much research on the mechanisms of portal hypertension has focused on liver fibrosis, less attention has been given to the role of intrahepatic and extrahepatic vascular dysfunction, particularly with respect to extrahepatic vasculature. While the role of hepatic fibrosis in cirrhotic portal hypertension is undeniable, the underlying mechanisms involving intrahepatic and extrahepatic vasculature are highly complex. Sinusoidal capillarization and endothelial dysfunction contribute to increased intrahepatic vascular resistance. Hemodynamic changes in the extrahepatic circulation, including splanchnic vasodilation and hyperdynamic circulation, play a significant role in the development of portal hypertension. Additionally, therapeutic strategies targeting these vascular mechanisms are diverse, including improvement of sinusoidal microcirculation, therapies targeting hepatic stellate cells activation, and pharmacological modulation of systemic vascular tone. Therefore, in this review, we will discuss the vascular-related mechanisms and treatment progress of portal hypertension in cirrhosis to provide a new theoretical basis and practical guidance for clinical treatment.

Interplay of gut microbiota, glucagon-like peptide receptor agonists, and nutrition: New frontiers in metabolic dysfunction-associated steatotic liver disease therapy

The gut-liver axis plays a crucial role in the development and progression of metabolic dysfunction-associated steatotic liver disease (MASLD). Key metabolites, including lipopolysaccharides, short-chain fatty acids (SCFAs), bile acids, and beneficial gut bacteria such as Bifidobacterium and Lactobacillus, are pivotal in this process. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) show promise in managing MASLD by promoting weight loss, enhancing insulin secretion, and improving liver health. They restore gut-liver axis functionality, and their effects are amplified through dietary modifications and gut microbiome-targeted therapies. Emerging research highlights the interplay between GLP-1 RAs and gut microbiota, indicating that the gut microbiome significantly influences therapeutic outcomes. Metabolites produced by gut bacteria, can stimulate glucagon-like peptide-1 (GLP-1) secretion, further improving metabolic health. Integrating dietary interventions with GLP-1 RA treatment may enhance liver health by modulating the gut microbiota-SCFAs-GLP-1 pathway. Future research is needed to understand personalized effects, with prebiotics and probiotics offering treatment avenues for MASLD.

Role of intestinal glucagon-like peptide-1 in hypoglycemia response impairment in type 1 diabetes

This study critically examines the novel findings presented by Jin et al, which explores the role of intestinal glucagon-like peptide-1 (GLP-1) in impaired counterregulatory responses to hypoglycemia in mice with type 1 diabetes. The study identifies intestinal GLP-1 as a significant determinant in the physiological responses to hypoglycemia, offering new insights into its potential implications for diabetes management. The editorial synthesizes these findings, discusses their relevance in the context of current diabetes research, and outlines potential avenues for future investigation of intestinal GLP-1 as a therapeutic target. This analysis underscores the need for continued research into the complex mechanisms underlying impaired hypoglycemia responses and highlights the potential of targeting intestinal GLP-1 pathways in therapeutic strategies for type 1 diabetes.

Gut microbiota: Implications in pathogenesis and therapy to cardiovascular disease (Review)

The gut microbiota refers to the diverse bacterial community residing in the gastrointestinal tract. Recent data indicate a strong correlation between alterations in the gut microbiota composition and the onset of various diseases, notably cardiovascular disorders. Evidence suggests the gut-cardiovascular axis signaling molecules released by the gut microbiota play a pivotal role in regulation. This review systematically delineates the association between dysbiosis of the gut microbiota and prevalent cardiovascular diseases, including atherosclerosis, hypertension, myocardial infarction and heart failure. Furthermore, it provides an overview of the putative pathogenic mechanisms by which dysbiosis in the gut microbiota contributes to the progression of cardiovascular ailments. The potential modulation of gut microbiota as a preventive strategy against cardiovascular diseases through dietary interventions, antibiotic therapies and probiotic supplementation is also explored and discussed within the present study.

Editor-in-Chief articles of choice and comments from January to June 2024

As the Editor-in-Chief of the World Journal of Gastroenterology , I carefully review all articles every week before a new issue’s online publication, including the title, clinical and research importance, originality, novelty, and ratings by the peer reviewers. Based on this review, I select the papers of choice and suggest pertinent changes (e.g. , in the title or text) to the company editors responsible for publication. This process, while time-consuming, is essential for assuring the quality of publications and highlighting important articles that readers may revisit.