Hepatic stellate cell-intrinsic role of SOCS1 in controlling hepatic fibrogenic response and the pro-inflammatory macrophage compartment during liver fibrosis

Hepatic stellate cells: balancing homeostasis, hepatoprotection and fibrogenesis in health and disease

In the past decades, the pathogenic role of hepatic stellate cells (HSCs) in the development of liver fibrosis and its complications has been deeply characterized, rendering HSCs a primary target for antifibrotic therapies. By contrast, the beneficial roles of HSCs in liver homeostasis and liver disease are only beginning to emerge, revealing critical regulatory and fibrosis-independent functions in hepatic zonation, metabolism, injury, regeneration and non-parenchymal cell identity. Here, we review how HSC mediators, such as R-spondin 3, hepatocyte growth factor and bone morphogenetic proteins, regulate critical and homeostatic liver functions in health and disease via cognate receptors in hepatocytes, Kupffer cells and endothelial cells. We highlight how the balance shifts from protective towards fibropathogenic HSC mediators during the progression of chronic liver disease (CLD) and the impact of this shifted balance on patient outcomes. Notably, the protective roles of HSCs are not accounted for in current therapeutic concepts for CLD. We discuss the concept that reverting the HSC balance from fibrogenesis towards hepatoprotection might represent a novel holistic treatment approach to inhibit fibrogenesis and restore epithelial health in CLD simultaneously.

T1/T2 mapping as a non-invasive method for evaluating liver fibrosis based on correlation of biomarkers: a preclinical study

BACKGROUND

Given the inherent limitations of invasive biopsy and the insufficient accuracy of liver-related serum biomarkers, there is an urgent need for the development of reliable, non-invasive imaging techniques for the diagnosis of liver fibrosis. This study aims to investigate the correlation between magnetic resonance imaging (MRI) T1/T2 mapping sequences and biomarkers of collagen deposition and ongoing systemic inflammation, and to evaluate the potential of T1/T2 mapping as a non-invasive method for the accurate diagnosis of liver fibrosis.

METHODS

A mouse model of carbon tetrachloride (CCl4)-induced liver fibrosis was established and T1/T2 mapping were performed at different weeks of treatment. The histopathological analysis, collagen quantification, and inflammatory factors measurements (IL-1, IL-6, TNF-α) were conducted to correlate MRI parameters with collagen deposition and inflammation. Statistical analysis was performed using IBM SPSS Statistics (version 22.0, Chicago, IL, USA) and Origin 2018 (OriginLab Corporation, Northampton, MA, USA).

RESULTS

The principal findings indicated that T1 and T2 values exhibited a progressive increase with the severity of fibrosis, demonstrating a positive correlation with collagen deposition and inflammatory factors, especially the hydroxyproline content (r = 0.880, P < 0.001). The HYP content exhibited a progressive increase with advancing fibrosis stages (ρ = 0.914, P < 0.001). Similarly, T1 values increased significantly across fibrosis stage(ρ = 0.854, P < 0.001). Statistical comparison of these coefficients revealed no significant difference (Z = 1.031, P = 0.303). ROC curve analysis showed that T1 mapping was more accurate than T2 mapping in detecting collagen deposition and inflammation.

CONCLUSIONS

This study highlighted the potential of T1/T2 mapping as non-invasive and quantitative biomarkers for diagnosing and staging liver fibrosis, providing new insights into the onset and progression of liver fibrosis.

NSUN2 knockdown inhibits macrophage infiltration in diabetic nephropathy via reducing N5-methylcytosine methylation of SOCS1

OBJECTIVE

N5-methylcytosine (m5C) methylation is involved in various disease progression; however, its role in diabetic nephropathy (DN) has not been studied. The aim of this study was to investigate the role of NSUN2 in DN and the underlying mechanism.

METHODS

Streptozotocin-induced experimental mouse model was generated to analyze the role of NSUN2 in vivo, and high glucose (HG)-treated Raw264.7 cells were used to assess the effect of NSUN2 on macrophage infiltration in vitro. The regulation of NSUN2 on SOCS1 m5C methylation was evaluated using m5C methylated RNA immunoprecipitation, luciferase reporter analysis, and RNA stability determination assay.

RESULTS

The results indicated that NSUN2 was highly expressed in the blood and kidney of DN mice. Knockdown of NSUN2 alleviated kidney damage, reduced blood glucose and urine albumin, and suppressed macrophage infiltration in DN mice. Moreover, NSUN2 interacted with SOCS1, and silenced NSUN2 inhibited m5C levels of SOCS1 to reduce SOCS1 mRNA stability. Additionally, interference with NSUN2 suppressed macrophage migration, invasion, and infiltration by positively regulating SOCS1 expression under HG conditions.

CONCLUSION

In conclusion, silencing of NSUN2 inhibits macrophage infiltration by reducing m5C modification of SOCS1, and thereby attenuates renal injury. The findings suggest a novel regulatory mechanism between NSUN2-mediated m5C modification and DN.

Diagnosis and Treatment of Liver Disease: Current Trends and Future Directions

This narrative review delves into the intricate landscape of liver diseases, providing a comprehensive background of the diverse conditions that afflict this vital organ. Liver diseases, ranging from viral hepatitis and non-alcoholic fatty liver disease (NAFLD) to cirrhosis and hepatocellular carcinoma (HCC), pose significant global health challenges. Understanding these diseases' multifaceted origins and progression is pivotal for developing effective diagnostic and therapeutic strategies. The epidemiology and etiology of liver diseases emphasize the global impact of viral hepatitis, with hepatitis B and C as significant contributors. Concurrently, the rising prevalence of NAFLD, linked to lifestyle factors and metabolic syndrome, underscores the intricate relationship between modern living and liver health. Chronic liver diseases often evolve insidiously, progressing from inflammation to fibrosis and, ultimately, to cirrhosis - a stage characterized by irreversible scarring and compromised function. The heightened risk of HCC in advanced liver disease stages further underscores the urgency of effective diagnostic and therapeutic interventions. The evolving landscape of non-invasive diagnostic tools is explored for their role in enabling early detection and accurate staging of liver diseases. In the realm of treatment, there is a continuous transition toward personalized medicine, customized to suit the unique profiles of individual patients. This shift encompasses a broad spectrum, ranging from personalized pharmacological interventions to lifestyle modifications and surgical options. Delving into innovative therapies, such as gene editing and immunomodulation, offers a glimpse into the promising future directions that have the potential to redefine the landscape of liver disease diagnosis and treatment.