Investigation on Anti-atherosclerosis Mechanism of Di'ao Xinxuekang Based on NLRP3 Inflammasome / 中国实验方剂学杂志

ABSTRACT

Objective:To investigate the effects of Di'ao Xinxuekang （DXXK） on NLRP3 inflammasome in mouse RAW264.7 macrophages and thoracic aorta of rats with atherosclerosis （AS）， so as to explore its anti-AS mechanism. Method:RAW264.7 cells were stimulated with oxidized low density lipoprotein （ox-LDL） and then intervened with MCC950 and DXXK. The contents of tumor necrosis factor-<italic>α</italic> （TNF-<italic>α</italic>） and interleukin-1<italic>β</italic> （IL-1<italic>β</italic>） were determined by enzyme linked immunosorbent assay （ELISA）. The mRNA and protein expression levels of Nod-like receptor protein 3 （NLRP3）， inflammasome adaptor protein apoptosis-associated speck-like protein containing CARD （ASC）， and cysteine-dependent aspartate-directed protease-1 （Caspase-1） were detected by real-time polymerase chain reaction （Real-time PCR） and Western blotting. Sixty male SD rats were randomly divided into the normal group， model group， atorvastatin group （2.0 mg·kg^-1）， as well as high-， medium-， and low-dose （100， 30， and 10 mg·kg^-1） DXKK groups， with 10 rats in each group. The rats were exposed to the high-fat diet and vitamin D₂ for inducing AS. The blood lipid level was measured using an automatic biochemical analyzer， followed by the calculation of AS index （AI）. The contents of serum TNF-<italic>α</italic> and IL-1<italic>β</italic> were determined by ELISA， and the mRNA and protein expression levels of NLRP3， ASC， and Caspase-1 in thoracic aorta were assayed by Real-time PCR and Western blotting. HE staining and Sirius red staining were conducted to observe the pathomorphological changes in the abdominal aorta and aortic sinus. Result:Compared with the normal group， the model group exhibited significantly increased TNF-<italic>α</italic> and IL-1<italic>β</italic> contents and up-regulated NLRP3， ASC， and Caspase-1 mRNA and protein expression in RAW264.7 cells （<italic>P</italic><0.01）. The above indexes in each drug administration group were significantly reduced in contrast to those in the model group （<italic>P</italic><0.05， <italic>P</italic><0.01）. The comparison with the model group showed that cholesterol （TC）， triglyceride （TG）， low-density lipoprotein cholesterol （LDL-C）， and AI in each DXXK group significantly declined， while the high-density lipoprotein cholesterol （HDL-C） was significantly elevated （<italic>P</italic><0.05， <italic>P</italic><0.01）. The levels of serum TNF-<italic>α</italic> and IL-1<italic>β</italic> and the mRNA and protein expression levels of NLRP3， ASC， and Caspase-1 in the thoracic aorta were decreased （<italic>P</italic><0.05， <italic>P</italic><0.01）. Abdominal aortic lesions and fibrous hyperplasia of aortic sinus were significantly improved. Conclusion:DXXK has a significant anti-AS effect， which is possibly related to the inhibition of NLRP3 inflammasome.