Reduced peripheral blood superoxide dismutase 2 expression in sickle cell disease.

Sickle cell disease (SCD), a hereditary form of chronic hemolytic anemia, is characterized by acute vascular occlusion and chronic complications as pulmonary hypertension (PH), a hallmark of higher mortality. This study aimed to determine peripheral blood expression of superoxide dismutase 2 (SOD2), a major mitochondrial antioxidant enzyme in SCD patients on the mRNA level and compared it with SOD2 expression in healthy individuals. It also aimed to detect possible differences in SOD2 expression among patients with/without specific SCD complications and to detect possible correlations with patient laboratory parameters. SOD2 mRNA levels were significantly lower in SCD patients in comparison with controls and correlated with red blood cell count, reticulocyte count, platelet count, C-reactive protein, ferritin, and brain natriuretic peptide values. SCD patients with echocardiographic indications of PH featured significantly reduced SOD2 expression in comparison with patients without such indications. Consequently, SOD2 expression emerges as a potential biomarker of PH in SCD being a link among hemolysis, inflammation, iron overload, oxidative stress, and SCD cardiopathy.

Data on eNOS T786 and G894T polymorphisms and peripheral blood eNOS mRNA levels in Sickle Cell Disease.

In this article, we present data on endothelial Nitric Oxide Synthase (eNOS) gene T786C and G894T polymorphisms in Greek steady-state Sickle Cell Disease patients in comparison to healthy controls. Moreover, eNOS mRNA levels were determined in peripheral blood samples from 18 patients and 9 controls. This article complements our recently published article named "Prognostic value of eNOS T786C and G894T polymorphisms in Sickle Cell Disease" (I. Armenis, V. Kalotychou, R. Tzanetea, Z. Kontogeorgiou, D. Anastasopoulou, M. Mantzourani, M. Samarkos, K. Pantos, K. Konstantopoulos, I. Rombos, 2016) [1].

Prognostic value of T786C and G894T eNOS polymorphisms in sickle cell disease.

Endothelial Nitric Oxide Synthase (eNOS) is crucial for vascular homeostasis. Polymorphisms T786C and G894T affect eNOS regulation and have been related to various diseases. Sickle Cell Disease (SCD), a clinically diverse chronic hemolytic anemia, implies impaired nitric oxide bioavailability. Our aim was to determine eNOS genotype for T786C and G894T polymorphisms in Greek patients with SCD and to elucidate its consequences and effects if any on clinical phenotype. Seventy nine steady state cases, mostly compound heterozygous for Sickle Cell anemia/beta thalassemia and 48 controls were measured. Peripheral blood DNA was extracted and genotyped with PCR-RFLPs and Sanger sequencing. Total RNA was extracted from 18 patients and 9 controls and eNOS mRNA levels were determined by real-time PCR. Genotypes, allele distribution and eNOS mRNA levels did not differ between patients and controls, or among patients with different beta globin gene mutations. The 786CC genotype was more common in S/S and ß0/S patients with retinopathy. Moreover, 894TT S/S and ß0/S patients tended to have a higher hematocrit than 894GG and GT ones. However, the T786C eNOS genotype does not seem to affect peripheral blood cell-derived eNOS mRNA levels, at least in steady state conditions. This work is the first one describing the effects of eNOS polymorphisms on different forms of SCD, the first enrolling SCD patients of Caucasian origin and the first determining eNOS mRNA levels in peripheral blood from steady-state SCD patients.