Genetic Polymorphisms in Endothelin-1 as Predictors for Long-Term Survival and the Cardiac Index in Patients Undergoing On-Pump Cardiac Surgery

Endothelin-1 gene polymorphism (G8002A) and endothelial monocyte-activating polypeptide II: Role in vascular dysfunction in pediatric patients with β-thalassemia major

BACKGROUND

Endothelin-1 (ET-1), a potent endogenous vasoconstrictor, stimulates production of reactive oxygen species. Endothelial monocyte-activating polypeptide-II (EMAP-II) is a multifunctional polypeptide.

AIM

To assess ET-1 gene polymorphism (G8002A) in pediatric patients with β-thalassemia major (β-TM) as a potential genetic marker for vascular dysfunction and its possible relation to EMAP II, oxidative stress and vascular complications.

METHODS

β-TM patients (n = 95) without symptomatic cardiac or renal disease were compared with 95 healthy controls. Markers of hemolysis, serum ferritin, urinary albumin-to-creatinine ratio, serum EMAP II, malondialdehyde (MDA) and antioxidant enzymes; superoxide dismutase (SOD), glutathione peroxidase (GPx), reduced glutathione (GSH), glutathione reductase and catalase were measured. ET-1 gene polymorphism (G8002A) was determined using polymerase chain reaction‑restriction fragment length polymorphism.

RESULTS

β-TM patients had significantly higher EMAP II than healthy controls. EMAP II was significantly higher among patients with cardiac disease, pulmonary hypertension (PH) risk, nephropathy, poor compliance to therapy and ferritin ≥ 2500 μg/L. There were significant correlations between EMAP II and transfusion index, LDH, ferritin and oxidative stress markers. The AA genotype of ET-1 gene polymorphism (G8002A) was significantly higher among β-TM patients than controls. The number of patients with cardiac disease, PH risk or nephropathy was significantly higher among AA genotype compared with GG and GA genotypes. Lactate dehydrogenase (LDH), serum ferritin, EMAP II, MDA, SOD and GPx were significantly higher in AA genotype.

CONCLUSION

ET-1 gene polymorphism (G8002A) could be a possible genetic marker for prediction of increased susceptibility to cardiopulmonary and renal complications among pediatric patients with β-TM.

The CTLA-4 rs231775 GG genotype is associated with favorable 90-day survival in Caucasian patients with sepsis

Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is a surface protein on T cells, that has an inhibitory effect on the host immune reaction and prevents overreaction of the immune system. Because the functional single-nucleotide polymorphism (SNP) rs231775 of the CTLA-4 gene is associated with autoimmune diseases and because of the critical role of the immune reaction in sepsis, we intended to examine the effect of this polymorphism on survival in patients with sepsis. 644 septic adult Caucasian patients were prospectively enrolled in this study. Patients were followed up for 90 days. Mortality risk within this period was defined as primary outcome parameter. Kaplan-Meier survival analysis revealed a significantly lower 90-day mortality risk among GG homozygous patients (n = 101) than among A allele carriers (n = 543; 22% and 32%, respectively; p = 0.03565). Furthermore, the CTLA-4 rs231775 GG genotype remained a significant covariate for 90-day mortality risk after controlling for confounders in the multivariate Cox regression analysis (hazard ratio: 0.624; 95% CI: 0.399-0.975; p = 0.03858). In conclusion, our study provides the first evidence for CTLA-4 rs231775 as a prognostic variable for the survival of patients with sepsis and emphasizes the need for further research to reveal potential functional associations between CTLA-4 and the immune pathophysiology of sepsis.