Hypoxia-inducible factor-1α polymorphisms link to coronary artery collateral development and clinical presentation of coronary artery disease

Hypoxia Inducible Factors as Central Players in the Pathogenesis and Pathophysiology of Cardiovascular Diseases

Cardiovascular (CV) diseases are the major cause of death in industrialized countries. The main function of the CV system is to deliver nutrients and oxygen to all tissues. During most CV pathologies, oxygen and nutrient delivery is decreased or completely halted. Several mechanisms, including increased oxygen transport and delivery, as well as increased blood flow are triggered to compensate for the hypoxic state. If the compensatory mechanisms fail to sufficiently correct the hypoxia, irreversible damage can occur. Thus, hypoxia plays a central role in the pathogenesis and pathophysiology of CV diseases. Hypoxia inducible factors (HIFs) orchestrate the gene transcription for hundreds of proteins involved in erythropoiesis, glucose transport, angiogenesis, glycolytic metabolism, reactive oxygen species (ROS) handling, cell proliferation and survival, among others. The overall regulation of the expression of HIF-dependent genes depends on the severity, duration, and location of hypoxia. In the present review, common CV diseases were selected to illustrate that HIFs, and proteins derived directly or indirectly from their stabilization and activation, are related to the development and perpetuation of hypoxia in these pathologies. We further classify CV diseases into acute and chronic hypoxic states to better understand the temporal relevance of HIFs in the pathogenesis, disease progression and clinical outcomes of these diseases. We conclude that HIFs and their derived factors are fundamental in the genesis and progression of CV diseases. Understanding these mechanisms will lead to more effective treatment strategies leading to reduced morbidity and mortality.

The association of functional polymorphisms in genes expressed in endothelial cells and smooth muscle cells with the myocardial infarction

Background

The association of platelet endothelial cell adhesion molecule 1 (PECAM1), hypoxia-inducible factor 1 subunit alpha (HIF1A), and KIAA1462 in myocardial infarction (MI) was investigated. The study included 401 Han Chinese MI patients and 409 controls. Three tag single-nucleotide polymorphisms (SNPs)—PECAM1 rs1867624, HIF1A rs2057482, and KIAA1462 rs3739998—were selected. SNP genotyping was performed by an improved multiplex ligation detection reaction assay. A systematic review and meta-analysis of studies including 3314 cases and 2687 controls on the association of 5 HIF1A SNPs and the overall risk of MI or coronary artery disease (CAD) was performed.

Results

The rs1867624 variants were associated with high TG concentrations (p = 0.040) and the rs2057482 variants were associated with decreased HDL-C in MI patients compared with the control group (p = 0.003). Rs2057482 SNP interacted with age to influence TC levels. The SNP of rs3739998 interacted with sex and hypertension to modulate CRE and TG levels, respectively (p < 3.04E-5-0.002). No association between the three SNPs and susceptibility to MI was found (p > 0.05 for all). In the meta-analysis of HIF1A, the rs11549465 C > T and rs10873142 T > C polymorphisms, but not rs2057482, rs11549467, and rs41508050, were correlated with overall MI or CAD risk.

Conclusions

Taken together, this study provides additional evidence that genetic variation of the PECAM1 rs1867624 and HIF1A rs2057482 can mediate lipid levels in MI patients.

Electronic supplementary material

The online version of this article (10.1186/s40246-018-0189-8) contains supplementary material, which is available to authorized users.

Association of hypoxia inducible factor-1 alpha exon 12 mutation in diabetic patients with and without diabetic foot ulcer

Hypoxia inducible factor 1 alpha (HIF-1α) is a key regulator of the genes involved in the cellular response to hypoxia. This study aims to determine the HIF-1α gene polymorphism and its association with protein expression in diabetic subjects with and without diabetic foot ulcers (DFU). A total of 529 patients with T2DM (N = 185), DFU (N = 199) and Control (N = 145) were accounted for the study. PCR-RFLP experiment was carried out in order to find the allelic and genotypic comparison of HIF-1α gene in various groups of patients. There was a highly increased frequency of GA, RR value of 3.533(2.099-5.950) with p-value of 0.0001 on DFU patients when compared to that of control subjects with risk allele of GA, RR value of 1.756 (1.294-2.384) with p-value of 0.00001. Thus, we found that there was a significant association of HIF-1α polymorphism in exon 12 among DFU patients when compared to control groups. The circulatory HIF-1α protein expression study indicated a decreased expression in DFU levels when compared to T2DM and control. Overall, the study showed that there is an association of HIF-1α polymorphism (G1970A) in diabetes and DFU patients when compared to the healthy group.

A comparison of gene expression profiles in patients with coronary artery disease, type 2 diabetes, and their coexisting conditions

Background

To support a hypothesis that there is an intrinsic interplay between coronary artery disease (CAD) and type 2 diabetes (T2D), we used RNA-seq to identify unique gene expression signatures of CAD, T2D, and coexisting conditions.

Methods

After transcriptome sequencing, differential expression analysis was performed between each disordered state and normal control group. By comparing gene expression profiles of CAD, T2D, and coexisting conditions, common and specific patterns of each disordered state were displayed. To verify the specific gene expression patterns of CAD or T2D, the gene expression data of GSE23561 was extracted.

Results

A strong overlap of 191 genes across CAD, T2D and coexisting conditions, were mainly involved in a viral infectious cycle, anti-apoptosis, endocrine pancreas development, innate immune response, and blood coagulation. In T2D-specific PPI networks involving 64 genes, TCF7L2 (Degree = 169) was identified as a key gene in T2D development, while in CAD-specific PPI networks involving 64 genes, HIF1A (Degree = 124), SMAD1 (Degree = 112) and SKIL (Degree = 94) were identified as key genes in the CAD development. Interestingly, with the provided expression data from GSE23561, the three genes were all up-regulated in CAD, and SMAD1 and SKIL were specifically differentially expressed in CAD, while HIF1A was differentially expressed in both CAD and T2D, but with opposite trends.

Conclusions

This study provides some evidences in transcript level to uncover the association of T2D, CAD and coexisting conditions, and may provide novel drug targets and biomarkers for these diseases.

Electronic supplementary material

The online version of this article (doi:10.1186/s13000-017-0630-7) contains supplementary material, which is available to authorized users.

Correlation between genetic polymorphisms within the MAPK1/HIF-1/HO-1 signaling pathway and risk or prognosis of perimenopausal coronary artery disease

BACKGROUND

Mitogen-activated protein kinase-1 (MAPK1), as well as its downstream factors of hypoxia-inducible factor-1 (HIF-1) and heme oxygenase-1 (HO-1), have been documented to be involved in modulating development of coronary artery disease (CAD).

HYPOTHESIS

Genetic mutations within the MAPK1/HIF-1/HO-1 signaling pathway could alter the risk of perimenopausal CAD in Chinese patients.

METHODS

Peripheral blood samples were gathered from 589 CAD patients and 860 healthy controls, and 12 potential single-nucleotide polymorphisms (SNPs) were obtained from HapMap database and previously published studies. Genotyping of SNPs was implemented with the TaqMan SNP Genotyping Assays. Odds ratios (OR) and 95% confidence intervals (CI) were utilized to evaluate the correlations between SNPs and CAD risk.

RESULTS

Regarding MAPK1 , rs6928 (OR: 1.71, 95% CI: 1.47-1.98, P < 0.05), rs9340 (OR: 0.85, 95% CI: 0.73-0.99, P < 0.05), and rs11913721 (OR: 0.70, 95% CI: 0.52-0.95, P < 0.05) were remarkably associated with susceptibility to perimenopausal CAD. Of these, rs9340 and rs11913721 were also regarded as protective factors for perimenopausal CAD patients. Moreover, results of HIF-1 indicated noticeable correlations between combined SNPs of rs1087314 and rs2057482 and risk of perimenopausal CAD (OR: 1.24, 95% CI: 1.01-1.53, P < 0.05; and OR: 0.71, 95% CI: 0.55-0.91, P < 0.05, respectively). Nonetheless, rs2071746 in HO-1 was found to be only associated with perimenopausal CAD risk (OR: 0.67, 95% CI: 0.58-0.78, P < 0.05).

CONCLUSIONS

The genetic mutations within MAPK1 (rs6928, rs9340, rs11913721), HIF-1 (rs1087314, rs2057482), and HO-1 (rs2071746) could alter susceptibility to perimenopausal CAD in this Chinese population.