Department of Pharmacology, Fudan University, Shanghai 201203, China.
Acta Biochim Biophys Sin (Shanghai). 2013 Mar;45(3):194-202. doi: 10.1093/abbs/gms121. Epub 2013 Jan 7.
In the present study, we investigated the effects of apolipoprotein A-I (apoA-I) on matrix metalloproteinase-2 (MMP-2) expression in vivo and in vitro. First, we detected the effects of apoA-I on aorta MMP-2, peroxisome proliferator-activated receptor α/γ (PPAR α/γ), cyclooxygenase-2 (COX-2), and nuclear factor kappa B (NF-κB) expressions in atherosclerotic rabbit models using immunohistochemical methods. The results showed that the expressions of MMP-2, COX-2, and NF-κB were decreased in aortas of atherosclerotic rabbits treated with apoA-I, while PPAR α/γ expression was increased. Then, we chose the important inflammation cells, macrophages to testify those effects in vitro. Macrophages were divided into six groups and treated with different concentrations of apoA-I, the mRNA expressions of MMP-2, PPAR α/γ, and COX-2 were then determined using reverse-transcription polymerase chain reaction, and protein expression of PPAR γ, NF-κB were detected by western blot analysis. The levels of MMP-2 and PPAR α in cultured supernatants were determined using enzyme-linked immunosorbent assays. Interestingly, the in vitro results were similar to the results of the in vivo study. After incubation with apoA-I for 24 h, the expressions of MMP-2, COX-2, and NF-κB were decreased, while PPAR α/γ expression was increased. In consideration of their particular roles in the process of making plaque stable in vivo and in vitro, we speculate that the inhibitory effect of apoA-I on MMP-2 expression may have a close relationship with the effects of apoA-I on PPAR α/γ, COX-2, and NF-κB expressions. Although further research is needed to clarify the underlying mechanisms of these effects, our findings provide a novel insight into the anti-atherosclerotic plaque rupture effects of apoA-I.
在本研究中，我们研究了载脂蛋白 A-I (apoA-I) 在体内和体外对基质金属蛋白酶-2 (MMP-2) 表达的影响。首先，我们采用免疫组化方法检测 apoA-I 对动脉粥样硬化兔模型主动脉 MMP-2、过氧化物酶体增殖物激活受体α/γ (PPARα/γ)、环氧化酶-2 (COX-2) 和核因子 kappa B (NF-κB) 表达的影响。结果表明，apoA-I 处理的动脉粥样硬化兔主动脉 MMP-2、COX-2 和 NF-κB 的表达减少，而 PPARα/γ 的表达增加。然后，我们选择了重要的炎症细胞——巨噬细胞，在体外验证这些作用。巨噬细胞分为六组，用不同浓度的 apoA-I 处理，然后用逆转录聚合酶链反应测定 MMP-2、PPARα/γ 和 COX-2 的 mRNA 表达，用 Western blot 分析测定 PPARγ、NF-κB 的蛋白表达，用酶联免疫吸附试验测定培养上清液中 MMP-2 和 PPARα 的水平。有趣的是，体外结果与体内研究结果相似。孵育 24 小时后，MMP-2、COX-2 和 NF-κB 的表达减少，而 PPARα/γ 的表达增加。考虑到它们在体内和体外稳定斑块过程中的特殊作用，我们推测 apoA-I 对 MMP-2 表达的抑制作用可能与 apoA-I 对 PPARα/γ、COX-2 和 NF-κB 表达的影响密切相关。虽然需要进一步研究来阐明这些作用的潜在机制，但我们的研究结果为 apoA-I 抗动脉粥样硬化斑块破裂作用提供了新的见解。
