Inhibition of hepatitis C virus by vitamin D

Metabolic Dysfunction-Associated Steatotic Liver Disease in Chronic Hepatitis C Virus Infection: From Basics to Clinical and Nutritional Management

Metabolic dysfunction-associated steatotic liver disease (MASLD) is closely associated with obesity and other cardiometabolic risk factors. MASLD has rapidly become the most common cause of liver disease worldwide, currently affecting 38% of the global population. Excess weight causes chronic inflammation and the activation of different pathways involved in liver damage. MASLD can progress from simple steatosis to steatohepatitis, giving way to its inflammatory component, metabolic dysfunction-associated steatohepatitis (MASH), previously recognized as non-alcoholic steatosis hepatitis (NASH). Chronic hepatitis C virus (HCV) infection remains a significant challenge to liver health as it triggers hepatic inflammation, metabolic disruption, and hepatic steatosis. The convergence of MASLD and chronic HCV infection can significantly alter the course of liver disease and accelerate the progression to severe liver damage. Currently, HCV treatment has a high cure rate. However, in patients who achieve a sustained virological response after treatment with direct-acting antivirals, weight gain, and excessive calorie intake may contribute to increased liver steatosis and a higher risk of liver disease progression. Therefore, the effective clinical and nutritional management of HCV patients, both before and after viral eradication, is crucial to reducing the risk of death from hepatocellular carcinoma. Understanding the complex interactions between MASLD and HCV infection is crucial for managing these patients appropriately. Herein, host and viral mechanisms inducing liver damage during the coexistence of MASLD and HCV infection are described, and their therapeutic and dietary management are discussed.

Chronic Hepatitis C Virus Infection, Extrahepatic Disease and the Impact of New Direct-Acting Antivirals

Chronic hepatitis C virus infection is an important cause of liver cirrhosis, hepatocellular carcinoma and death. Furthermore, it is estimated that about 40-70% of patients develop non-hepatic alterations in the course of chronic infection. Such manifestations can be immune-related conditions, lymphoproliferative disorders and metabolic alterations with serious adverse events in the short and long term. The introduction of new Direct-Acting Antivirals has shown promising results, with current evidence indicating an improvement and remission of these conditions after a sustained virological response.

Discovery of a fused bicyclic derivative of 4-hydroxypyrrolidine and imidazolidinone as a new anti-HCV agent

Hepatitis C virus (HCV) infection causes severe liver diseases and remains a major global public health concern. Current direct-acting antiviral (DAA)-based therapies that target viral proteins involving HCV genome replication are effective, however a minority of patients still fail to cure HCV, rendering a window to develop additional antivirals particularly targeting host functions involving in HCV infection. Here, we utilized the HCV infection cell culture system (HCVcc) to screen in-house compounds bearing host-interacting preferred scaffold for the antiviral activity. Compound HXL-10, a novel fused bicyclic derivative of pyrrolidine and imidazolidinone, was identified as a potent anti-HCV agent with a low cytotoxicity and high specificity. Mechanistic studies showed that HXL-10 neither displayed a virucidal effect nor inhibited HCV genomic RNA replication. Instead, HXL-10 might inhibit HCV assembly by targeting host functions. In summary, we developed a novel anti-HCV agent that may potentially offer additive benefits to the current anti-HCV DDA.

Vitamin D-VDR Novel Anti-Inflammatory Molecules-New Insights into Their Effects on Liver Diseases

There is consistent evidence that vitamin D deficiency is strongly associated with liver dysfunction, disease severity, and poor prognosis in patients with liver disease. Vitamin D and its receptor (VDR) contribute to the regulation of innate and adaptive immune responses. The presence of genetic variants of vitamin D- and VDR-associated genes has been associated with liver disease progression. In our recent work, we summarized the progress in understanding the molecular mechanisms involved in vitamin D-VDR signaling and discussed the functional significance of VDR signaling in specific cell populations in liver disease. The current review focuses on the complex interaction between immune and liver cells in the maintenance of liver homeostasis and the development of liver injury, the interplay of vitamin D and VDR in the development and outcome of liver disease, the role of vitamin D- and VDR-associated genetic variants in modulating the occurrence and severity of liver disease, and the therapeutic value of vitamin D supplementation in various liver diseases. The association of the vitamin D-VDR complex with liver dysfunction shows great potential for clinical application and supports its use as a prognostic index and diagnostic tool.