Pioglitazone and Ezetimibe combination improves Liver histopathology and biochemistry in experimental MASH models

Metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) are common clinico-pathological conditions that affecting over 30% of adults worldwide. Insulin resistance and hepatic lipid accumulation constitute the metabolic foundation of MASLD/MASH. Although previous studies have shown limited efficacy of activation of single PPARs (PPARα or PPARγ), ongoing clinical trials suggest that dual and pan-PPAR agonists may have a broader and more potent therapeutic effect on MASH by simultaneously targeting different inter-related mechanisms in this multisystem disease. Therefore, we hypothesized that a combination of PPARγ agonist (to enhance insulin sensitivity) with lipid lowering therapy (similar to PPARα) could have similar or better effects compared to PPARα/γ dual agonists. In the current study, we have investigated a novel combination of pioglitazone (a PPAR γ/α agonist) and ezetimibe (a cholesterol absorption inhibitor) in two different MASH animal models. We expected that anti-cholesterol absorption property of ezetimibe can augment the poor PPAR-α agonist property of pioglitazone in terms of lipid sensitivity in regulating steatosis. We tested pioglitazone at 2-3-fold reduced clinical dose (15mg/day) in combination to ezetimibe, since there are safety concerns associated with higher doses (30mg and 45mg, daily). Our results revealed that combination of low dose pioglitazone, with ezetimibe hold the ability to regulate the steatosis, hepatocyte inflammation and ballooning, which resulted in superior effects in terms of NAS as well as fibrosis score compared to pioglitazone alone (30mg/kg). Moreover, in vitro studies in human liver microsomes and mouse hepatocytes did not show any drug-drug interaction between pioglitazone and ezetimibe. Overall, this study provides a potential possibility for the clinical treatment of MASH with combination of pioglitazone and ezetimibe.