Perilla seed oil (PSO), rich in alpha-linolenic acid (ALA), has been traditionally used to relieve exterior syndrome and promote digestion, with modern studies confirming its anti-hyperlipidemic and anti-atherosclerotic properties. This study investigated the lipid-lowering effects of PSO and its underlying mechanisms in high-fat-diet-induced hyperlipidemic rats. Chemical standardization by UPLC-MS and GC-MS identified 591 compounds in PSO, with ALA accounting for 57.5% of its composition. The PSO administration significantly improved the general condition of hyperlipidemic rats, reduced body weight, lowered serum total cholesterol and LDL-C levels, and alleviated liver tissue injury and lipid accumulation. Serum metabolomics analysis revealed that PSO upregulated ALA and eicosapentaenoic acid while downregulating pro-inflammatory metabolites, including arachidonic acid, prostaglandin H2, and prostaglandin E2. Integrated network pharmacology and molecular docking studies identified the PI3K/Akt/NOS3 pathway as the primary signaling mechanism, which was further confirmed by Western blot analysis showing that PSO upregulated expression of p-PI3K, p-Akt, and NOS3 proteins. These results demonstrated that PSO-ameliorated hyperlipidemia, through PI3K/Akt/NOS3 pathway activation, coordinately modulated fatty acid metabolism and endogenous inflammatory responses. Our findings provided scientific evidence supporting PSO as a dietary intervention for managing hyperlipidemia and related metabolic disorders.

Background: Perilla seed oil (PSO) is a high-nutritional-value oil and widely used in functional foods, and derives from the mature seeds of Perilla frutescens. This study aimed to systematically evaluate the nutritional characteristics and safety of PSO, as well as to investigate its lipid-modulating effects and the underlying changes in gut microbiota in hyperlipidemic conditions. Methods: The nutritional characteristics of PSO (prepared via seed cleaning, cold-pressing, filtration, and solvent extraction) were evaluated by comparing it with 15 representative vegetable oils, focusing on fatty acid composition, total phenolic and flavonoid contents, metal elements, and physicochemical indices. The safety of PSO was assessed through acute oral toxicity testing in Kunming mice (doses: 2.5, 5, 10 g/kg) with general observations, histopathological examination, and serum biochemical analysis. Additionally, a high-fat diet (HFD)-induced hyperlipidemic Sprague-Dawley (SD) rat model was established to explore PSO’s lipid-modulating effects and its regulatory role in gut microbiota, using serum biochemical detection, liver pathology examination, 16S rRNA gene sequencing, and short-chain fatty acid (SCFA) analysis. Results: PSO possessed the highest α-linolenic acid (ALA) content among the tested oils, along with a favorable unsaturated fatty acid ratio. Notably, PSO was rich in zinc and free of toxic elements. In HFD-fed rats, 10 g/kg PSO significantly reduced serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels, increased high-density lipoprotein cholesterol (HDL-C), and alleviated hepatic damage. Moreover, PSO modulated gut microbiota by enriching probiotic populations and elevating intestinal production of short-chain fatty acids (SCFAs), particularly propionate and butyrate. Conclusions: PSO is a nutritionally rich and safe edible oil with notable lipid-modulating properties, highlighting its potential as a dietary intervention for preventing lipid metabolism disorders.