Manganese superoxide dismutase, glutathione peroxidase and catalase gene polymorphisms and clinical outcomes in acute kidney injury.

INTRODUCTION: The aim of this study was to evaluate the potential association of single gene polymorphisms of manganese superoxide dismutase (MnSOD), glutathione peroxidase 1 (GPX1) and catalase (CAT) with clinical outcomes of acute kidney injury (AKI). MATERIALS AND METHODS: Ninety AKI patients and 101 healthy volunteers were included in the study. Determination of MnSOD rs4880, GPX1 rs1050450 and CAT rs769217 polymorphisms was performed using real-time polymerase chain reaction amplification. The duration of hospitalization of AKI patients, dialysis and intensive care requirements, sepsis, oliguria and in-hospital mortality rates were assessed. RESULTS: The MnSOD, GPX1 and CAT genotypes and allele frequencies of AKI patients did not differ significantly from those of healthy controls. In patients with a T allele in the ninth exon of the CAT gene, intensive care requirements were greater than those of patients with the CC genotype (p = 0.04). In addition, sepsis and in-hospital mortality were observed significantly more frequently in patients with a T allele in the ninth exon of the CAT gene (p = 0.03). Logistic regression analysis determined that bearing a T allele was the primary determinant of intensive care requirements and in-hospital mortality, independent of patient age, gender, presence of diabetes and dialysis requirements (OR 6.10, 95% CI 1.34-27.81, p = 0.02 and OR 10.25, 95% CI 1.13-92.80, p = 0.04, respectively). CONCLUSION: Among AKI patients in the Turkish population, hospital morbidity and mortality were found to be more frequent in patients bearing a T allele of the rs769217 polymorphism of the CAT gene.

Effects of short-term hyperglycemia on the vasoconstriction of the aorta.

BACKGROUND/AIM: To investigate vasoconstrictor responses of healthy blood vessels to short-term hyperglycemic conditions such as postprandial hyperglycemia, gestational diabetes mellitus, and steroid-induced diabetes. MATERIALS AND METHODS: Female Wistar rat aorta rings were incubated in normal (11 mM) and high (22 mM and 44 mM) glucose concentrations for 4 h. Responses of vasoconstriction were measured in reaction to serotonin (10-5 M), phenylephrine (10-6 M), and KC1 (60 mM) compared to the ambient condition, including different glucose concentrations. RESULTS: While the responses of vasoconstriction to KC1 were increased in the presence of Krebs' solution with high glucose, no statistically significant changes were observed in the reaction to serotonin and phenylephrine. In addition, malondialdehyde levels were increased in hyperglycemic conditions. CONCLUSION: Short-term hyperglycemia may lead to augmented contractile response in aorta rings through several mechanisms, and our results showed that oxidative stress is probably one of them.

Esophageal muscle cell interaction with biopolymers.

BACKGROUND: The in vitro interactions of esophageal smooth muscle cells (SMCs) with synthetic absorbable polymers were tested and artificial muscle tissues harvested from subcutaneous implantation were examined. MATERIAL/METHODS: Esophageal tissue samples from adult and fetal (25-day gestational age) rabbits were cut into small pieces and cultured in Dulbecco's Modified Eagle Medium supplemented with 10% fetal bovine serum. Growing cells were identified as SMCs by immunostaining for anti-actin and anti-myosin antibodies. Equal volumes of agar gel and medium were mixed and used for 3-D culture. 5x10(5) cells and 1 mg polyglycolic acid (PGA) and poly-lactide-co-glycolide acid (PLGA) fibers were seeded in six-well tissue culture plates. On days 2 and 7 growing cells were counted by a hemocytometer and cell-polymer interactions were evaluated with light microscopy. Adult and fetal SMCs were seeded onto the PGA and PLGA scaffolds, cultivated for two weeks, and implanted subcutaneously on the backs of the rabbits. Cell-polymer implants were retrieved after four weeks and muscle formation was evaluated histologically and immunohistochemically. RESULTS: Growing cells stained positive for actin and myosin proteins. Cell-polymer interactions were poor after 24 hours, whereas intensive attachment to the fibers was detected 48 hours following cultivation. Both fiber materials supported cell proliferation. PLGA scaffolds improved muscle formation more efficiently than PGA, and fetal and adult SMCs showed similar mass quality. CONCLUSIONS: Scaffolds are important as cell-carrying vehicles, and material-cell interactions should be tested before application. A 3-D culture prepared with agar gel and medium is practical for testing material toxicity.