Matrix metalloproteinase gene polymorphisms and susceptibility to systemic sclerosis.

The major pathological hallmark of the systemic sclerosis (SSc) is skin and internal organ fibrosis, which results from normal tissue architecture alterations and extracellular matrix (ECM) protein deposition. ECM components are degraded by matrix metalloproteinases (MMP). Promoter region polymorphisms in MMP genes may influence gene expression, resulting in an imbalance between ECM protein production and degradation. Here, we analyzed MMP1 -1607 1G/2G (rs1799750), MMP3 -1171 5A/6A (rs3025058), and MMP9 -1562 C/T (rs3918242) polymorphisms in relation to susceptibility to SSc and its clinical features. The patient group included 98 individuals with longstanding or recently diagnosed disease, meeting the American College of Rheumatology or LeRoy and Medsger criteria for SSc; the control group included 100 healthy blood donors. All participants were of European descent. Genotyping was performed by polymerase chain reaction followed by restriction digestion. Genotype and allele frequencies of MMP polymorphisms were similar between the two groups. In secondary analyses, significantly higher frequency of 1G/2G genotype from MMP1 polymorphism was observed for patients testing positive for antinuclear autoantibodies (P = 0.007), while 1G/1G genotype was associated with interstitial lung disease development (P = 0.018). The 6A/6A genotype from MMP3 polymorphism was absent in patients with calcinosis (P = 0.011), while the MMP3 5A/5A genotype correlated with the presence of anti-topoisomerase I antibodies (P = 0.009) and reduced diffusing capacity for carbon monoxide (P = 0.024). These results suggest that MMP polymorphisms are not associated with SSc susceptibility, although MMP1 and MMP3 variants are associated with specific SSc clinical and laboratory features.

Influence of CYP2C19 on Helicobacter pylori eradication in Brazilian patients with functional dyspepsia.

The aim of this study was to examine the effect of polymorphisms in the cytochrome P450 (CYP) 2C19 gene (CYP2C19) on the Helicobacter pylori eradication rate in Brazilian patients with functional dyspepsia. Adults diagnosed with functional dyspepsia based on the ROME III criteria and infected with H. pylori were recruited to this study. The patients were subjected to gastrointestinal endoscopy and the H. pylori status was defined when both urease test and histopathology results were negative or positive. The patients were treated with proton pump inhibitor-based triple therapy (omeprazole, amoxicillin, and clarithromycin). CYP2C19*2 and CYP2C19*3 were genotyped by polymerase chain reaction-restriction fragment length polymorphism. One hundred and forty-eight patients (81.8% women) with a mean (± SD) age of 46.1 (12.2) years were included in this study. Based on the CYP2C19 genotypes, the patients were classified as homozygous extensive metabolizer (HomEM; 67.6%), heterozygous extensive metabolizer (HetEM; 26.3%), or poor metabolizer (PM; 6.1%). The H. pylori eradication rates in patients with HomEM, HetEM, and PM were 85.0, 89.7, and 100.0% (P = 0.376), respectively. The included study population comprised a high frequency of patients carrying the HomEM genotype. Although the genotypes of CYP2C19 variants were not statistically significant, the results of this study suggest a possible effect of the PM genotype on the efficacy of H. pylori eradication.