Abstract: BACKGROUND: Activation of nuclear factor-κB/NOD-like receptor thermal protein domain associated protein 3 (NLRP3) signaling leads to endothelial dysfunction, oxidative stress, and plays a key role in the initiation of lipid metabolism disorders and arteriosclerosis. However, currenty, the effect of walnut oil and peanut oil on skeletal muscle inflammatory factors in arteriosclerotic rats remains unclear.
OBJECTIVE: To discuss the effect and mechanism of walnut oil and peanut oil on atherosclerosis.
METHODS: Forty 8-week-old SD male rats were randomly divided into normal control group (n=10) and high fat group (n=30) after 1 week of adaptive feeding. The atherosclerosis model was established by high-fat diet combined with vitamin D3 injection. The rats with successful modeling were randomly divided into model group (n=10), peanut oil group (n=8) and walnut oil group (n=8). The latter two groups were gavaged with peanut oil or walnut oil for 4 weeks (5 days/week, 1.2 g/kg per day). After the intervention, ELISA was used to detect the related indexes of blood lipids in rats. The morphological changes of aorta were observed by hematoxylin-eosin staining. The RT-qPCR and western blot assay were used to detect nuclear factor-κB, NLRP3, Caspase-1, interleukin-1β, interleukin-18 mRNA and nuclear factor-κB, NLRP3, interleukin-1β protein expression levels in skeletal muscle. The protein expressions of nuclear factor-κB and NLRP3 were detected by immunofluorescence immunohistochemical staining.
RESULTS AND CONCLUSION: (1) Compared with the normal control group, the aortic wall of rats in the model group was thickened, the damage and lipid precipitation were more serious, the blood lipid levels and arteriosclerosis index were significantly increased (P < 0.01). The mRNA levels of nuclear factor-κB, NLRP3, Caspase-1, interleukin-1β, and interleukin-18, and the protein expressions of nuclear factor-κB, NLRP3, and interleukin-1β in skeletal muscle were significantly increased (P < 0.01). (2) Compared with model group, the vulnerable area of aortic tissue in peanut oil group and walnut oil group was significantly reduced, the levels of total cholesterol, triglyceride, low density lipoprotein cholesterol in serum, and atherosclerosis index were decreased (P < 0.01), and the mRNA expressions of nuclear factor-κB, NLRP3, Caspase-1, interleukin-1β, and interleukin-18 and the protein expressions of nuclear factor-κB, NLRP3, and interleukin-1β in skeletal muscle were significantly decreased (P < 0.01 or P < 0.05). (3) Compared with peanut oil group, the serum total cholesterol, triglyceride, and low density lipoprotein cholesterol levels in walnut oil group were significantly decreased (P < 0.01 or P < 0.05), and the mRNA levels of nuclear factor-κB, NLRP3, Caspase-1, interleukin-18, and the protein levels of nuclear factor-κB, NLRP3, interleukin-1β decreased significantly in skeletal muscle (P < 0.01 or P < 0.05). It is concluded that both peanut oil and walnut oil have ameliorative effect on atherosclerotic damage, which may be related to nuclear factor-κB/NLRP3 signaling pathway, and walnut oil has better ameliorative effect than peanut oil. 

中国组织工程研究杂志出版内容重点：组织构建；骨细胞；软骨细胞；细胞培养；成纤维细胞；血管内皮细胞；骨质疏松；组织工程

Key words: walnut oil, peanut oil, atherosclerosis, rat, signaling pathway, skeletal muscle, inflammatory factor, engineered tissue construction