Regulation Of Expression Of MMP9,ABCA,SR-BI And Its Mechanism By Acetyl Salicylic Acid In THP-1 Macrophage

Aspirin, namely Acetyl salicylic acid, is a typical antipyretic and pain killer, which is usually prescribed to alleviate the headache,toothache,muscleache and fever through inhibiting the sythensize of COX and setting obstacle for the production of PG that has close association with the inflammation. In inflammation tissue (e.x. atheroscleorosis), amount of PG exist.The pathology mechanism of atherosclerosis is still not be understood, with the development of molecule biology techniques, scholars found that inflammation is the basic pathology phenomena of the mutiple-factor diseases, given it is the chronic inflammational diseases involved in many inflammatory cells and inflammatory factors, many scholars suggested that the atherosclerosis should be changed to athero-inflammation. PG affects the local inflammation and mediate the general physiological response, and its rate-limiting enzyme COX-2 is expressed in human atherosclerosis plaque. At present, COX has been the target of drugs to prevent atherosclerosis, and the expression level has also been an important element to evaluate whether the drug can inhibit the inlammation. Macrophage, the most predominant leucocyte in atherosclerosis plaque, promotes the production of foam cell through the following ways, such as mediating the production of inflammatory mediator and binding the lipoprotein by virtue of surface receptors.Considering the anti-inflammation of aspirin and the inflammation mechanism of atherosclerosis, the projects focus on the study whether aspirin can regulate the MMP9, which involved in the stability of atherosclerosis plaque, and SR-BI, ABCA1, which can control the cholesterol efflux, and we elucidated that ASA problely can alleviate the atherosclerosis development and following related accidents.In our study, the THP-1 cell line as a research object, we investigate the potential effect of ASA on the expression and function of MMP9,ABCA,SR-BI and discuss the probable mechanism. The main methods and results as following:1. THP-1 monocyte was successfully induced by 200nM Phorbol ester (PMA) and become macrophage after 48h, which was consistent with the characteristic of macrophage, so we set up a solid foundation for the following experiment. MTT assays shows that low-dose ASA have no effect on the proliferation of THP-1 macrophage and wasn't concentration-dependent and time-dependent.2. RT-PCR shows that ASA can inhibit the MMP-9 expression in transcription level in THP-1 macrophage and the inhibiting effect is best in 1200μM ASA, the relate expression level is only 0.53 of control group.3. Zymographic assays shows that the activity of MMP-9 at 24h group was higher then 48h group and 72h group, and the relative expression leve is 0.72, 0.56 compared to the control group. The significant result is the 1200μM can markably inhibit the activity of MMP9.4. Western blotting results shows that ASA can inhibit the nuclear translocation of NF-кB p65 submit.5. ASA can increase the ABCA1,SR-BI expression in THP-1 macrophage and is dose-dependently rising. When the concentration of ASA reaches to 1200μM, the m RNA relative expression level, which is 1.8 and 2.1 respectively, has a significant difference with the control group. The protein relative expression level is 1.7 and 1.6 and similar to mRNA level.6. After the THP-1 was successfully induced by PMA, oil red"o"affirmed that the foam cell induction is successful, the cholesterol efflux assay revealed that ASA can promote the cholesterol efflux mediated by Apo-A, at the concentration is 600μM,1200μM, the cholesterol efflux level had a significant different with the control group.