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Introduction: Liver fibrosis is a significant global health burden that lacks effective therapies. It can progress to cirrhosis and hepatocellular carcinoma (HCC). Aberrant hedgehog pathway activation is a key driver of fibrogenesis and cancer, making hedgehog inhibitors potential antifibrotic and anticancer agents. Methods: We evaluated simvastatin and STA-9090, alone and combined, in rats fed a high-fat diet (HFD) and exposed to diethylnitrosamine and thioacetamide (DENA/TAA). Simvastatin inhibits HMG-CoA reductase, depleting cellular cholesterol required for Sonic hedgehog (Shh) modification and signaling. STA-9090 directly inhibits HSP90 chaperone interactions essential for Shh function. We hypothesized combining these drugs may provide liver protective effects through complementary targeting of the hedgehog pathway. Endpoints assessed included liver function tests, oxidative stress markers, histopathology, extracellular matrix proteins, inflammatory cytokines, and hedgehog signaling components. Results: HFD and DENA/TAA caused aberrant hedgehog activation, contributing to fibrotic alterations with elevated liver enzymes, oxidative stress, dyslipidemia, inflammation, and collagen deposition. Monotherapies with simvastatin or STA-9090 improved these parameters, while the combination treatment provided further enhancements, including improved survival, near-normal liver histology, and compelling hedgehog pathway suppression. Discussion: Our findings demonstrate the enhanced protective potential of combined HMG CoA reductase and HSP90 inhibition in rats fed a HFD and exposed to DENA and TAA. This preclinical study could help translate hedgehog-targeted therapies to clinical evaluation for treating this major unmet need. [ABSTRACT FROM AUTHOR]

• Hedgehog signaling has been recognized as potentially promoting NASH. • Cholesterol affects hedgehog signaling by modifying PTCH1 and SMO activity. • HSP90 plays a role in the stability of SMO and GLI proteins. • Lovastatin and PU-H71 combined therapy effectively suppressed hedgehog signaling. • Lovastatin and PU-H71 improved biochemical parameters in rats with NASH. Non-alcoholic steatohepatitis (NASH) is characterized by liver inflammation, fat accumulation, and collagen deposition. Due to the limited availability of effective treatments, there is a pressing need to develop innovative strategies. Given the complex nature of the disease, employing combination approaches is essential. Hedgehog signaling has been recognized as potentially promoting NASH, and cholesterol can influence this signaling by modifying the conformation of PTCH1 and SMO activity. HSP90 plays a role in the stability of SMO and GLI proteins. We revealed significant positive correlations between Hedgehog signaling proteins (Shh, SMO, GLI1, and GLI2) and both cholesterol and HSP90 levels. Herein, we investigated the novel combination of the cholesterol-lowering agent lovastatin and the HSP90 inhibitor PU-H71 in vitro and in vivo. The combination demonstrated a synergy score of 15.09 and an MSA score of 22.85, as estimated by the ZIP synergy model based on growth inhibition rates in HepG2 cells. In a NASH rat model induced by thioacetamide and a high-fat diet, this combination therapy extended survival, improved liver function and histology, and enhanced antioxidant defense. Additionally, the combination exhibited anti-inflammatory and anti-fibrotic potential by influencing the levels of TNF-α, TGF-β, TIMP-1, and PDGF-BB. This effect was evident in the suppression of the Col1a1 gene expression and the levels of hydroxyproline and α-SMA. These favorable outcomes may be attributed to the combination's potential to inhibit key Hedgehog signaling molecules. In conclusion, exploring the applicability of this combination contributes to a more comprehensive understanding and improved management of NASH and other fibrotic disorders. The cholesterol-lowering drug lovastatin can disrupt Shh signaling by reducing cholesterol biosynthesis and influencing interaction between PTCH and Shh. PU-H71, an HSP90 inhibitor, could offer promise by inhibiting the chaperone machinery and impacting key proteins within the Shh pathway such as SMO and GLI1. Ch, cholesterol; GLI1, glioma-associated oncogene family zinc finger 1; HSP90, heat shock protein 90; PTCH, patched; Shh, sonic hedgehog; SMO, smoothened; SUFU, suppressor of fused. [Display omitted] [ABSTRACT FROM AUTHOR]

Liver cancer stands as the fourth leading global cause of death, and its prognosis remains grim due to the limited effectiveness of current medical interventions. Among the various pathways implicated in the development of hepatocellular carcinoma (HCC), the hedgehog signaling pathway has emerged as a crucial player. Itraconazole, a relatively safe and cost-effective antifungal medication, has gained attention for its potential as an anticancer agent. Its primary mode of action involves inhibiting the hedgehog pathway, yet its impact on HCC has not been elucidated. The main objective of this study was to investigate the effect of itraconazole on diethylnitrosamine-induced early-stage HCC in rats. Our findings revealed that itraconazole exhibited a multifaceted arsenal against HCC by downregulating the expression of key components of the hedgehog pathway, shh, smoothened (SMO), and GLI family zinc finger 1 (GLI1), and GLI2. Additionally, itraconazole extended survival and improved liver tissue structure, attributed mainly to its inhibitory effects on hedgehog signaling. Besides, itraconazole demonstrated a regulatory effect on Notch1, and Wnt/β-catenin signaling molecules. Consequently, itraconazole displayed diverse anticancer properties, including anti-inflammatory, antiangiogenic, antiproliferative, and apoptotic effects, as well as the potential to induce autophagy. Moreover, itraconazole exhibited a promise to impede the transformation of epithelial cells into a more mesenchymal-like phenotype. Overall, this study emphasizes the significance of targeting the hedgehog pathway with itraconazole as a promising avenue for further exploration in clinical studies related to HCC treatment. [ABSTRACT FROM AUTHOR]