Attenuation of diet-induced hepatic steatosis by capric acid-rich MLM structured lipids in an obese mouse model.

Metabolic dysfunction-associated steatotic liver disease (MASLD) has emerged as a major hepatic manifestation of obesity and insulin resistance and represents a growing global health burden. Dietary lipid structure plays a decisive role in lipid metabolic fate and hepatic lipid accumulation, highlighting structured lipids as a promising nutritional strategy to modulate metabolic dysfunction. To evaluate whether capric acid (C10)-based medium-long-medium (MLM) structured lipids can remodel hepatic lipid metabolism and promote the reversal of established MASLD in a diet-induced obese mouse model. MASLD was induced in male C57BL/6 J mice by feeding a long-chain saturated high-fat diet for 8 weeks. Subsequently, mice received a 4-week dietary intervention with microencapsulated C10-enriched MLM structured lipids. Body weight, adipose tissue accumulation, insulin resistance markers, adipokines, biochemical parameters of lipid metabolism, liver enzyme activity, tissue fatty acid profiles, and hepatic histopathology were evaluated. The structured lipid intervention resulted in marked metabolic improvements, including a 40% reduction in body weight gain, normalization of insulin resistance (HOMA-IR ≈1), and significant decreases in hepatic triglycerides (55%) and cholesterol (30%). Histological analysis revealed a 66% reduction in total hepatic steatosis, with substantial decreases in both macrovesicular and microvesicular fat accumulation. Improvements were also observed in adipokine profiles and liver injury markers, indicating recovery of hepatic metabolic function. Capric acid-based MLM structured lipids effectively reversed diet-induced hepatic steatosis and improved systemic metabolic dysfunction in obese mice. These findings highlight lipid molecular structuring as a powerful food-based strategy for the development of functional dietary fats targeting MASLD and related metabolic disorders.