Emerging natural products against obesity and metabolic dysfunction-associated steatotic liver disease/metabolic dysfunction-associated steatohepatitis: Direct target discovery and mechanistic insights.

Obesity is a multifactorial metabolic condition characterized by dysregulated lipid accumulation and systemic energy imbalance with escalating global prevalence. This chronic disease drives a spectrum of life-threatening comorbidities, including metabolic dysfunction-associated steatotic liver disease (MASLD) and its progressive form, metabolic dysfunction-associated steatohepatitis (MASH), which now represent a primary cause of liver-related morbidity and transplantation. Both conditions share pathophysiological underpinnings such as insulin resistance, chronic inflammation, and mitochondrial dysfunction, creating a vicious cycle where obesity exacerbates hepatic steatosis and fibrosis. Although US Food and Drug Administration-approved antiobesity agents such as glucagon-like peptide-1 receptor agonists (eg, semaglutide) demonstrate weight loss efficacy, their long-term utility is constrained by gastrointestinal intolerance and variable effects on hepatic outcomes. Similarly, the recent approval of resmetirom for MASH, though groundbreaking, leaves unresolved challenges in durability, accessibility and some adverse effects including gastrointestinal reaction. The intricate molecular crosstalk linking adipose and hepatocyte dysfunction necessitates innovative therapeutics targeting shared pathophysiological pathways or novel molecular targets. Natural products, with inherent structural diversity and multitarget potential, offer a promising avenue for dual intervention in the obesity-MASH continuum. This review systematically evaluates emerging endogenous metabolites and plant-derived compounds, elucidating their directly validated molecular targets and preclinical evidence for metabolic reprogramming against obesity and MASLD/MASH. Furthermore, it synthesizes translational insights from natural product research and clinical trial experiences of related synthetic agonists. By integrating mechanistic discovery with a critical assessment of developmental challenges, this review aims to advance strategic frameworks for the concurrent management of obesity and MASLD/MASH. SIGNIFICANCE STATEMENT: Obesity-driven metabolic dysfunction-associated steatotic liver disease and steatohepatitis are leading causes of liver morbidity with limited treatment options. This review systematically evaluates natural products as multitarget therapeutics for these interconnected conditions. By integrating evidence of their efficacy and target mechanisms with modern discovery approaches, this study emphasizes pathways for clinical translation and aims to stimulate future research into novel, mechanism-based interventions.