Phytosterol-enriched corn and wheat germ blended oil improves lipid metabolism in hyperlipidemia via the AMPK/PPARα/CPT1 pathway.

Abstract

While plant sterol-enriched oils are known to improve lipid profiles, the effects and mechanisms of phytosterol-enriched corn and wheat germ blended oil (PCWGO) remain unclear. This study evaluated the lipid-regulating effects of PCWGO in individuals with borderline dyslipidemia and hyperlipidemic rats, and explored the underlying mechanisms. A randomized, single-blind, parallel-controlled trial was conducted in 60 adults assigned to PCWGO or peanut oil (PO) for 3 months. Serum lipids and oxidative stress markers were measured. In parallel, high-fat diet-induced hyperlipidemic rats received PCWGO or PO for 8 weeks, followed by assessment of lipid levels, liver histology, and AMPK/PPARα/CPT1 pathway proteins. In the human trial, the PCWGO group showed significant reductions in serum total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and apolipoprotein B (Apo B), along with increased superoxide dismutase (SOD), glutathione (GSH), and total antioxidant capacity (TAOC), and decreased reactive oxygen species (ROS) (P < 0.05). In hyperlipidemic rats, PCWGO similarly reduced serum TC, TG, and LDL-C after eight weeks (P < 0.05). Western blot analysis showed upregulated hepatic expression of phosphorylated AMP-activated protein kinase (p-AMPK), peroxisome proliferator-activated receptor α (PPARα), and carnitine palmitoyltransferase 1 (CPT1) in the PCWGO group versus the PO group (P < 0.05). PCWGO effectively improved lipid metabolism in both humans and animal models and may have beneficial effects on oxidative status. Its hypolipidemic effects may be related to activation of the AMPK/PPARα/CPT1 pathway, promoting fatty acid β-oxidation. These findings support phytosterol-enriched blended germ oil as a potential dietary strategy for managing dyslipidemia.