The Association Between Extracellular Matrix Metalloproteinase Inducer Polymorphisms and Coronary Heart Disease: A Potential Way to Predict Disease.

Extracellular matrix metalloproteinase inducer (EMMPRIN) had been reported to be involved in the occurrence and development of coronary heart disease (CHD) in previous studies. This study aimed to investigate whether single nucleotide polymorphisms of EMMPRIN and matrix metalloproteinase-9 (MMP-9) contributed to the onset and severity of CHD. One thousand seventy patients suspected to have CHD were enrolled into the study. Each patient had undergone coronary angiogram, and the severity of coronary artery stenosis was assessed by Gensini score. Eight hundred twelve patients were confirmed to have CHD, while 258 patients were selected as non-CHD control. All patients were genotyped for five EMMPRIN polymorphisms (rs8259, rs28915400, rs4919859, rs6758, and rs8637) and one MMP-9 polymorphism (rs3918242) by polymerase chain reaction-restriction fragment length polymorphism and confirmed by direct sequencing. EMMPRIN polymorphism rs8259 and MMP-9 polymorphism rs3918242 were found to be associated with CHD (rs8259: AT vs. AA, adjusted odds ratio [OR] = 2.038, adjusted 95% confidence interval [CI] = 1.080-3.847, p = 0.028; rs3918242: CT vs. CC, adjusted OR = 0.607, adjusted 95% CI = 0.403-0.916, p = 0.017, TT vs. CC, adjusted OR = 2.559, adjusted 95% CI = 1.326-4.975, p = 0.006). No crossover effects were observed although a single environmental or genetic factor had an impact on the occurrence of CHD. The value of the Gensini score revealed that severity of CHD decreased in the rs3918242 CT carriers in both the male and female population. Our study suggested that EMMPRIN rs8259 and MMP-9 rs3918242 polymorphisms may contribute to pathological process of CHD. It could play a critical role in the prediction of CHD.

Effects of high glucose on proliferation and function of circulating fibrocytes: Involvement of CXCR4/SDF­1 axis.

The present study aimed to further investigate the effects of high glucose on the function of circulating fibrocytes and its underlying mechanisms. The total peripheral blood mononuclear cells were obtained from normal glucose tolerance patients and type 2 diabetic mellitus patients. Circulating fibrocytes were stimulated with different glucose concentrations for different time periods (24, 48 and 72 h). Cell proliferation was determined by Cell Counting Kit­8 assay. The expression of connective tissue growth factor (CTGF) was detected by western blotting. The expression of COL­I was detected by flow cytometry. The apoptotic bodies of cells were detected by fluorescence microscopy after Hoechst33258 staining. The invasive and migration abilities of fibrocytes were detected by Transwell chamber assay. Secretion of stromal cell­derived factor 1 (SDF­1) was measured by ELISA. The circulating fibrocytes showed a typical spindle­shape and were double­positive for cluster of differentiation 45 (green) and COL­I (red). Compared with the 5.5 mmol/l glucose group, a high glucose concentration significantly promoted the proliferation of circulating fibrocytes and showed the most significant effects at 30 mmol/l after treatment for 48 h. AMD3100 showed no effects on the proliferation of circulating fibrocytes. Flow cytometry revealed that 30 mmol/l glucose significantly promoted the expression of COL­I vs. 5.5 mmol/l glucose group (P<0.01), while AMD3100 reversed this (P<0.05). Hoechst33258 staining showed no differences in the apoptotic bodies between experimental groups (P>0.05). Western blotting revealed that the expression of CTGF was decreased significantly by AMD3100 pretreatment (P<0.01). Transwell chamber assay showed that 30 mmol/l glucose significantly promoted the invasive and transfer abilities (P<0.01) of fibrocytes when compared with the 5.5 mmol/l glucose group. While AMD3100 reversed the cell migratory effects induced by high glucose (P<0.01). In addition, the secretion of SDF­1 stimulated by 30 mmol/l glucose DMEM showed no differences compared with 5.5 mmol/l glucose DMEM (P>0.05). High glucose stimulated the expressions of CTGF and COL­I, and promoted migration of circulating fibrocytes via the CXC chemokine receptor 4/SDF­1 axis.

Isobaric tags for relative and absolute quantitation­based proteomics reveals potential novel biomarkers for the early diagnosis of acute myocardial infarction within 3 h.

Acute myocardial infarction (AMI) is one of the most common and life­threatening cardiovascular diseases. However, the ability to diagnose AMI within 3 h is currently lacking. The present study aimed to identify the differentially expressed proteins of AMI within 3 h and to investigate novel biomarkers using isobaric tags for relative and absolute quantitation (ITRAQ) technology. A total of 30 beagle dogs were used for establishing the MI models successfully by injecting thrombin powder and a polyethylene microsphere suspension. Serum samples were collected prior to (0 h) and following MI (1, 2 and 3 h). ITRAQ­coupled liquid chromatography­mass spectrometry (LC­MS) technology was used to identify the differentially expressed proteins. The bioinformatics analysis selected several key proteins in the initiation of MI. Further analysis was performed using STRING software. Finally, western blot analysis was used to evaluate the results obtained from ITRAQ. In total, 28 proteins were upregulated and 23 were downregulated in the 1 h/0 h group, 28 proteins were upregulated and 26 were downregulated in the 2 h/0 h group, and 24 proteins were upregulated and 19 were downregulated in the 3 h/0 h group. The Gene Ontology (GO) annotation and functional enrichment analysis identified 19 key proteins. Protein­protein interactions (PPIs) were investigated using the STRING database. GO enrichment analysis revealed that a number of key proteins, including ATP synthase F1 subunit ß (ATP5B), cytochrome c oxidase subunit 2 and cytochrome c, were components of the electron transport chain and were involved in energy metabolism. The western blot analysis demonstrated that the expression of ATP5B decreased significantly at all three time points (P<0.01), which was consistent with the ITRAQ results, whereas the expression of fibrinogen γ chain increased at 2 and 3 h (P<0.01) and the expression of integrator complex subunit 4 increased at all three time points (P<0.01), which differed from the ITRAQ results. According to the proteomics of the beagle dog MI model, ATP5B may serve as the potential biomarkers of AMI. Mitochondrial dysfunction and disruption of the electron transport chain may be critical indicators of early MI within 3 h. These finding may provide a novel direction for the diagnosis of AMI.