Arbidol attenuates liver fibrosis and activation of hepatic stellate cells by blocking TGF-β1 signaling

Galactose-modified erythrocyte membrane fusion liposomes enable the targeted delivery of drug nanoparticles to the liver

The safe and efficient delivery of chemicals and biologics remains crucial for liver disease therapy. In this study, we developed a targeted drug delivery system utilizing a galactose-modified erythrocyte membrane coating technique and drug liposome nanoparticles, which were further optimized using orthogonal experiments and response surface analysis. The specificity, precision, accuracy, and stability exhibited satisfactory performance in bioanalytical analysis. Specifically, targeting ligands (Gal-DSPE-PEG3400) were efficiently inserted into red blood cell (RBC) membranes using a facile insertion method. When Gal-DSPE-PEG3400-RBC was fused with fenofibrate liposome nanoparticles (FNB-Lip) by co-extrusion, the resulting galactose-modified erythrocyte membrane fusion liposome nanoparticles (Gal-RBC-FNB-Lip) showed long-term stability, excellent biocompatibility, prolonged retention time, and superior liver accumulation and therapeutic efficacy. These qualities make it suitable for effective drug delivery. The findings of this study will provide a fundamental basis for research and development of liver-targeted drugs and offer novel insights into the treatment of clinical liver diseases.

TRPC6 suppresses liver fibrosis by inhibiting hepatic stellate cell activation via CaMK4-CREB pathway

BACKGROUND AND PURPOSE

Genetic ablation or inhibition of the cation channel TRPC6 is protective against renal, cardiac and intestinal fibrosis. However, TRPC6 expression is decreased in patients with liver diseases. Here, we explored the role of TRPC6 in liver fibrosis and the underlying mechanism.

EXPERIMENTAL APPROACH

Bile duct ligation and thioacetamide gavage were used to model liver fibrosis in C57BL/6J mice. Western blotting, immunolabelling and qPCR were employed for protein and mRNA expression. Liver injury/fibrosis were assessed using serum alanine transaminase and aspartate transaminase assays, haematoxylin-eosin, Masson and Sirius red staining. Adenoviruses were used to overexpress TRPC6 and CREB1Y134F. ChIP and dual-luciferase reporter assays were performed to test the direct inhibition of Acta2 transcription by CREB.

KEY RESULTS

TRPC6 protein levels were decreased in fibrotic liver tissues from both patients and mice, with the decrease being more robust in fibrotic areas. In hepatic stellate cells (HSCs), TRPC6 ablation aggravated liver injury and fibrosis, which was alleviated by overexpressing TRPC6. In primary cultured HSCs, deletion of TRPC6 exacerbated self-activation of HSCs, which was reversed by restoration of TRPC6 expression. Mechanistically, TRPC6 suppressed HSC activation through CaMK4-mediated CREB phosphorylation. CREB directly interacted with the promoter region of Acta2 to inhibit its transcription. Expression of a constitutively active form of CREB1 (CREB1Y134F) in HSCs attenuated BDL-induced liver injury/fibrosis in TRPC6 knockout mice.

CONCLUSION AND IMPLICATIONS

Deficiency of TRPC6 aggravates liver injury/fibrosis through augmentation of HSC activation. Increasing TRPC6 expression/function would be therapeutically beneficial for fibrotic liver diseases.

COVID-19-related liver injury: Mechanisms, diagnosis, management; its impact on pre-existing conditions, cancer and liver transplant: A comprehensive review

AIMS

This review explores the mechanisms, diagnostic approaches, and management strategies for COVID-19-induced liver injury, with a focus on its impact on patients with pre-existing liver conditions, liver cancer, and those undergoing liver transplantation.

MATERIALS AND METHODS

A comprehensive literature review included studies on clinical manifestations of liver injury due to COVID-19. Key areas examined were direct viral effects, drug-induced liver injury, cytokine storms, and impacts on individuals with chronic liver diseases, liver transplants, and the role of vaccination. Data were collected from clinical trials, observational studies, case reports, and review literature.

KEY FINDINGS

COVID-19 can cause a spectrum of liver injuries, from mild enzyme elevations to severe hepatic dysfunction. Injury mechanisms include direct viral invasion, immune response alterations, drug toxicity, and hypoxia-reperfusion injury. Patients with chronic liver conditions (such as alcohol-related liver disease, nonalcoholic fatty liver disease, cirrhosis, and hepatocellular carcinoma) face increased risks of severe outcomes. The pandemic has worsened pre-existing liver conditions, disrupted cancer treatments, and complicated liver transplantation. Vaccination remains crucial for reducing severe disease, particularly in chronic liver patients and transplant recipients. Telemedicine has been beneficial in managing patients and reducing cross-infection risks.

SIGNIFICANCE

This review discusses the importance of improved diagnostic methods and management strategies for liver injury caused by COVID-19. It emphasizes the need for close monitoring and customized treatment for high-risk groups, advocating for future research to explore long-term effects, novel therapies, and evidence-based approaches to improve liver health during and after the pandemic.