Genetic polymorphisms of myeloperoxidase and their effect on hypertension

Polymorphisms in myeloperoxidase and tissue inhibitor of metalloproteinase-1 genes and their association with preeclampsia in the Chinese Han population

Hypertensive disorders of pregnancy (HDP) are multifaceted syndromes unique to pregnancy, characterized by increased blood pressure, edema, and proteinuria. Patients with HDP exhibit signs of endothelial dysfunction, possibly linked to increased myeloperoxidase (MPO) level and aberrant oxidative stress. Additionally, altered level of tissue inhibitor of metalloproteinase-1 (TIMP1) protein is associated with placental ischemia, hypoxia, and maternal vascular endothelial damage. Preeclampsia (PE) represents a critical stage of HDP that poses severe threats to maternal and fetal safety. This study aimed to determine the relationship between MPO and TIMP1 polymorphisms and the risk of PE in the Chinese Han population. Single nucleotide polymorphisms (SNPs), including MPO rs7208693, MPO rs2243828, and TIMP1 rs6609533, were genotyped in 170 patients with PE and 303 control participants. No significant association was observed between MPO polymorphisms (rs7208693 and rs2243828) and the risk of PE, whereas significant association between the TIMP1 rs6609533 A > G SNP and PE susceptibility was found. Specifically, individuals with the GG or AG genotypes had elevated risk of PE compared to those harboring the AA genotype. Furthermore, in the PE group, patients carrying the G allele were more likely to experience fetal growth restriction (FGR). In the non-PE group, the association between the G allele and the risk of FGR was not evident. In conclusion, the TIMP1 rs6609533 G allele in Chinese Han women was identified as a risk factor for PE. Our results indicated that the TIMP1 rs6609533 SNP can serve as a biomarker for the clinical diagnosis and treatment of PE.

Genetic polymorphisms associated with reactive oxygen species and blood pressure regulation

Hypertension is the most prevalent cause of cardiovascular disease and kidney failure, but only about 50% of patients achieve adequate blood pressure control, in part, due to inter-individual genetic variations in the response to antihypertensive medication. Significant strides have been made toward the understanding of the role of reactive oxygen species (ROS) in the regulation of the cardiovascular system. However, the role of ROS in human hypertension is still unclear. Polymorphisms of some genes involved in the regulation of ROS production are associated with hypertension, suggesting their potential influence on blood pressure control and response to antihypertensive medication. This review provides an update on the genes associated with the regulation of ROS production in hypertension and discusses the controversies on the use of antioxidants in the treatment of hypertension, including the antioxidant effects of antihypertensive drugs.

Role of Myeloperoxidase in Patients with Chronic Kidney Disease

Chronic kidney disease (CKD) is a worldwide public health problem. Patients with CKD have a number of disorders in the organism, and the presence of oxidative stress and systemic inflammation in these patients is the subject of numerous studies. Chronic inflammation joined with oxidative stress contributes to the development of numerous complications: accelerated atherosclerosis process and cardiovascular disease, emergence of Type 2 diabetes mellitus, development of malnutrition, anaemia, hyperparathyroidism, and so forth, affecting the prognosis and quality of life of patients with CKD. In this review we presented the potential role of the myeloperoxidase enzyme in the production of reactive/chlorinating intermediates and their role in oxidative damage to biomolecules in the body of patients with chronic kidney disease and end-stage renal disease. In addition, we discussed the role of modified lipoprotein particles under the influence of prooxidant MPO intermediates in the development of endothelial changes and cardiovascular complications in renal failure.

Gender-specific protective effect of the -463G>A polymorphism of myeloperoxidase gene against the risk of essential hypertension in Russians

The purpose of this study was to investigate whether a common polymorphism -463G>A (rs2333227) in the promoter of myeloperoxidase (MPO) gene, an oxidant enzyme producing hypohalogenic radicals, is associated with the risk of essential hypertension (EH) in Russian population. A total of 2044 unrelated subjects including 1256 EH patients and 788 normotensive controls were recruited for this study. Genotyping of the MPO gene polymorphism was done using TaqMan-based assay. A genotype -463GA was associated with decreased risk of EH (odds ratio = 0.82; 95% confidence interval: 0.68-1.00) at a borderline significance level (P = .05). The gender-stratified analysis showed that a carriage of the -463GA and -463AA genotypes is associated with decreased EH risk only in females (odds ratio = 0.74, 95% confidence interval: 0.56-0.96; P = .02). To the best of our knowledge, this is the first study reporting a negative association between the -463G>A polymorphism of the MPO gene and EH risk. Molecular mechanisms by which MPO gene is involved in the pathogenesis of EH are discussed.

Personalized hypertension management in practice

The revolution occurring in genomic and personalized medicine is likely to have a significant impact on the management of hypertension. However, from the perspective of translating new knowledge into clinical practice, progress has been slow. This review article summarizes recent advances in hypertension-related diagnostics while also offering new perspective on hypertension management for the future. Such new perspectives will likely require a paradigm shift toward more integrated and holistic approaches for better prevention and treatment of hypertension in both individuals and the population as a whole.

Relation of myeloperoxidase-463G/A polymorphism with metabolic syndrome and its component traits in Egyptian women

CONTEXT

Myeloperoxidase is a heme protein secreted by activated macrophages and generates intermediates that oxidize lipoproteins. Myeloperoxidase-463G/A is a functional polymorphism involved in regulation of myeloperoxidase expression.

OBJECTIVE

The aim of this study is to assess the relation of myeloperoxidase-463G/A polymorphism with metabolic syndrome and its component traits in Egyptian women from the Suez Canal area.

METHODS

The study includes 100 healthy female subjects and 100 metabolic syndrome patients. The component traits of metabolic syndrome are determined and the genotypes of the polymorphisms assessed using the PCR-RFLP technique.

RESULTS

There was no significant difference in the allele frequencies between the metabolic syndrome and control groups. However, the GA and AA genotypes were associated with lower total cholesterol, LDL-C, systolic and diastolic blood pressure in the patients.

CONCLUSION

Myeloperoxidase-463G/A polymorphism is not associated with the incidence of metabolic syndrome.

Do salivary and serum collagenases have a role in an association between obstructive sleep apnea syndrome and periodontal disease? A preliminary case-control study

OBJECTIVES

Despite increasing evidence for an association of obstructive sleep apnea syndrome (OSAS) and periodontal disease, the pathophysiological linking mechanisms remain unclear. This study aims to evaluate the salivary and serum matrix metalloproteinase-2, -8, -9 (MMP-2, -8, -9), tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), myeloperoxidase (MPO), neutrophil elastase (NE), neutrophil gelatinase-associated lipocalin (NGAL), as well as degree of activation of MMP-2, -9 of patients with and without OSAS.

DESIGN

A total of 50 individuals were included in the study. There were 13, 17 and 20 individuals, respectively in the control (non-OSAS) group, mild-to-moderate OSAS and severe OSAS groups. Saliva, serum samples and clinical periodontal parameters were collected. Biofluid samples were analysed by immunofluorometric assay (IFMA), enzyme-linked immunosorbent assay (ELISA), western immunoblotting and gelatine zymography. Statistical analyses were performed using D'Agostino-Pearson omnibus normality test, Kruskal-Wallis test and Spearman rho rank correlation analysis.

RESULTS

There were no statistically significant differences in clinical periodontal parameters between the study groups. Salivary NE and proMMP-2 levels were significantly lower in the OSAS groups than the control group (p<0.05). Serum proMMP-9 concentration and the degree of MMP-9 activation in saliva were significantly lower in the severe OSAS group than the control group (p<0.05). There were significant correlations between salivary and serum proMMP-9 and -2 concentrations (p<0.05). Serum proMMP-2, NE and salivary proMMP-9 and -2 negatively correlated with indicators of OSAS severity (p<0.05).

CONCLUSIONS

The present findings do not support a pathophysiological link between the severity of OSAS and clinical periodontal status via neutrophil enzymes or MMPs.