Résumé
ObjectiveTo investigate the therapeutic effect of Scutellariae Radix-Coptidis Rhizoma （SRCR） on atherosclerosis （AS） in mice and the effect of SRCR on macrophage pyroptosis in plaques via NOD-like receptor thermal protein domain-associated protein 3 （NLRP3） inflammasomes. MethodApoE-/- mice were fed with a high-fat diet for the modeling of AS and randomized into model， atorvastatin （5 mg·kg-1）， and low-， medium-， and high-dose （1.95， 3.9， 7.8 g·kg-1， respectively） SRCR groups. Normal C57BL/6J mice were selected as the control group. After 8 weeks of administration， hematoxylin-eosin staining was used to observe the pathological status of the aortic plaque. The lipid accumulation in aortic plaque was observed by oil red O staining. The serum levels of total cholesterol （TC）， triglyceride （TG）， high-density lipoprotein cholesterol （HDL-C）， and low-density lipoprotein cholesterol （LDL-C） in mice were measured. Immunofluorescence double staining was employed to detect the co-localized expression of EGF-like module-containing mucin-like hormone receptor-like 1 （EMR1）/NLRP3 and EMR1/gasdermin D （GSDMD）. The serum levels of interleukin-1β （IL-1β） and interleukin-18 （IL-18） were determined by enzyme-linked immunosorbent assay （ELISA）. The protein levels of NLRP3， apoptosis-associated speck-like protein （ASC）， Caspase-1， cleaved Caspase-1， GSDMD， N-terminus of GSDMD （GSDMD-NT）， pro-IL-1β， IL-1β， and IL-18 were determined by Western blot， and the mRNA levels of NLRP3， ASC， Caspase-1， GSDMD， IL-1β， and IL-18 were determined by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. ResultCompared with the control group， the model group showed obvious plaques， elevated serum levels of TG， TC， LDL-C， IL-1β， and IL-18 （P<0.01）， lowered serum level of HDL-C （P<0.01）， and up-regulated expression of NLRP3 inflammasomes and molecules related to pyroptosis in the aortic plaques （P<0.01）. Compared with the model group， SRCR， especially at the medium and high doses， alleviated the plaque pathology， reduced the lipid content in plaques （P<0.05， P<0.01）， recovered the serum lipid levels （P<0.05）， reduced the macrophage recruitment （P<0.01）， activation of NLRP3 inflammasomes， and pyroptosis in aortic root plaques （P<0.05）， lowered the serum IL-1β and IL-18 levels （P<0.01）， and down-regulated the protein levels of NLRP3， ASC， Caspase-1， cleaved Caspase-1， GSDMD， GSDMD-NT， pro-IL-1β， IL-1β， and IL-18 （P<0.05） and the mRNA levels of NLRP3， ASC， Caspase-1， GSDMD， IL-1β， and IL-18 in the aortic tissue （P<0.05）. ConclusionSRCR exerts a therapeutic effect on high-fat diet-induced AS in mice by inhibiting the activation NLRP3 inflammasomes and reducing the pyroptosis of macrophages in plaques.