Chronic liver disease and fibrosis: A review of emerging biomarkers and therapeutic targets

Abstract

Chronic liver disease (CLD) and fibrosis represent a significant global health burden, driven by a range of etiologies including viral hepatitis, alcohol abuse, and non-alcoholic fatty liver disease (NAFLD). These conditions often progress to cirrhosis, liver failure, and hepatocellular carcinoma (HCC), underscoring the urgent need for effective diagnostic and therapeutic strategies. Emerging biomarkers and therapeutic targets offer promising avenues for early diagnosis and intervention in CLD and fibrosis. Biomarkers are crucial for the early detection and monitoring of CLD and fibrosis, allowing for timely therapeutic intervention. Serum biomarkers such as liver enzymes (ALT, AST), bilirubin, and platelet count have traditionally been used, but they lack specificity and sensitivity. Recent advances have identified novel biomarkers with improved diagnostic performance. For instance, serum levels of fibrosis markers like hyaluronic acid, procollagen type III N-terminal peptide (P3NP), and tissue inhibitor of metalloproteinases-1 (TIMP-1) have shown potential in assessing liver fibrosis. Additionally, non-invasive imaging techniques such as transient elastography and magnetic resonance elastography provide quantitative measures of liver stiffness, correlating with fibrosis stage. The pathogenesis of liver fibrosis involves complex interactions between hepatocytes, hepatic stellate cells (HSCs), and the extracellular matrix (ECM). HSCs play a central role in fibrogenesis by transforming into myofibroblasts that secrete collagen and other ECM components. Targeting the activation and proliferation of HSCs has emerged as a promising therapeutic strategy. Small molecule inhibitors, such as those targeting the PDGF and TGF-? signaling pathways, have shown efficacy in preclinical models. Furthermore, antifibrotic agents like simtuzumab, an anti-LOXL2 monoclonal antibody, are being evaluated in clinical trials for their potential to halt or reverse fibrosis progression. Another promising approach involves the modulation of the gut-liver axis. Dysbiosis and increased intestinal permeability contribute to liver inflammation and fibrosis. Probiotics, prebiotics, and fecal microbiota transplantation (FMT) are being explored for their potential to restore gut homeostasis and mitigate liver injury. Additionally, the role of the immune system in fibrosis has gained attention, with immune checkpoint inhibitors and anti-inflammatory agents being investigated for their ability to modulate immune responses and reduce fibrosis. Keywords:  Chronic Liver Disease, Fibrosis, Biomarkers, Therapeutic Targets.