Expression Of ADRP And PKC In Atherosclerotic Plaque And Their Relationship With The Stability Of Plaque

For many years, modification and accumulation of lipid in arterial endothelium has been considered the beginning of atherosclerosis. Recent studies have found that adipose differentiation-related protein (ADRP, adipophilin) is an important role in the pathogenesis of atherosclerotic disease. ADRP is a lipid droplets around the main protein, which distributed a large number of lipid droplets in the presence of cells. It is a specific marker of lipid accumulation.In early differentiation in the fat cells, it has high expression, but in mature fat cells its expression was decreased. ADRP involved in adipocyte lipid metabolism, lipid droplets and liver triglyceride (TG) synthesis and metabolism. Also promote macrophage, smooth muscle cell foam, and promote the long-chain fatty acid intake, milk secretion. ADRP expression was associated with the pathological processes of atherosclerosis, insulin resistance and tumor closely. Studies have confirmed that ADRP expression in animal models of atherosclerosis increased, but the mechanism in the formation of atherosclerosis is not fully understood. Recent years` study found, individe the plaque into stable plaque and unstable plaque based on anatomical characteristics atherosclerotic is more reasonable. Because of its tendency to thrombosis and rapid development of acute vascular events can lead to "criminal patch", how to effectively identify unstable plaques and inhibit plaque formation and development becomes more important. At present, the research of ADRP expression in unstable plaques is relatively less. This experiment has done research on this, and to explore the expression of protein kinase C in unstable atherosclerotic plaques, which may participate the pathogenesis of atherosclerosis.This study based on deriving atheroscleros sample from lower limb artery. Limited in clinical conditions the control group failed to obtain lower limb artery, take the mesenteric artery as control group, they are all medium-sized artery. By HE staining the plaque lesion group are divided into two subgroups :stable and unstable plaque group. Observe the ADRP expression in atherosclerotic plaques by immunohistochemistry and reverse transcription polymerase chain reaction, and observe the expression of both PKC and CD36 in atherosclerotic plaques with different stability by immunohistochemistry experiments for they may have association with the Regulation of ADRP`s expression.Objective: To evaluate the expressions of adipophilin, PKC and CD36 in atherosclerotic lesion plaque, and to further explore the relationship between plaque stability and their expression.Methods: Take the popliteal artery in 18 patients of arteriosclerosis obliterans who take treatment of amputation or prosthetic vessel replacement as the experimental group, Individe the samples at prominent plaque place into two part, one fixed with 10% formaldehyde solution for HE staining and immunohistochemical analysis, the other freese in -80℃refrigerator for PCR. Take mesenteric artery from pations ofgastrectomy and without risk factors of atherosclerosis as normal control group, samples were also divided into two parts for formaldehyde fixed and frozen in -80℃refrigerator. Take all of formaldehyde fixed paraffin embedded samples, sections, first HE staining. Select the HE stained specimens with clear structure for the study. Then divided the tissues into stable plaque and unstable plaque group in accordance with the reference criteria Currently widely used for the classification of plaque instability(lipid core plaque area of more than 40%). Frozen samples of atherosclerosis group were divided into a stable plate group and an unstable plaque group according to the corresponding mark. Specimens of each group take ADRP,PKC and CD36 immunohistochemistry respectively. Select five clear stain specimens from stable plaque group and unstable plaque group respectively ,observe each specimen under a 200 optical microscope of consecutive detection of 4-5 fields of vision. Images collected under the same conditions and analyzed the relative average gray of the observation site. Frozen samples of atherosclerosis group were divided into a stable plate group and an unstable plaque group according to the corresponding mark. Randomly selected six samples from unstable plaque group and control group respectively.Take all the samples in the stablegroup, determination for PT-PCR detection of ADRP expression. Analyze the PCR products by agarose gel electrophoresis, and analyze the optical density of electrophoresis strip by gel electrophoresis image ,determine their content with the ratio of the target gene and internal reference GAPDH . The experimental data were expressed with mean±standard deviation ( x±S) ,comparisons between groups were analyzed using analysis of variance and t test, completed by the software SPSS11.0, determined significant difference by P<0.05.Results: 1.HE pathological staining: intima of vascular wall is smooth in normal control group, luminal side of endothelial cells stained blue, arranged in neat rows ,medial smooth muscle cells were spindle, no hyperplasia. Experimental group are of severely damaged vessel wall and typical of formation plaque, intimal thickening, fibrosis, vascular intimal the lumen prominent, visible plaque lipid deposition and foam cells can be seen. There are large number of inflammatory cells and intimal proliferation of smooth muscle cells in endomembrane, endocardium and calcium deposition in necrotic material, significant proliferation of medial smooth muscle cells and calcification were spotty or flake.2. Semi-quantitative immunohistochemical analysis showed that: ADRP,PKC and CD36 expressed high in the experimental group , they are slightly higher in unstable plaques than in stable plaques. 3.RT-PCR test results: ADRP expression increase in atherosclerotic plaques, it is higher in unstable plaques than in stable plaques.Conclusion: 1. ADRP,PKC and CD36 in the atherosclerotic plaque are upregulationed; 2.the expression of ADRP and PKC in unstable plaques is higher than in stable plaques ;3.The high expression of ADRP,PKC and CD36 in plaques may be associated with instability of plaque.