Pulmonary oxidative stress in diabetic rats exposed to hyperoxia

Abstract

Pulmonary oxidative stress in diabetic rats exposed to hyperoxia 1 1-Experimental SurgeryActa Cir Bras. 2017;32(7):503-514 AbstractPurpose: To evaluate the pulmonary oxidative stress in diabetic rats exposed to hyperoxia for 90 minutes. Methods: Forty male Wistar rats were divided into four groups, each one containing 10 animals, according to the oxygen concentration to which they were exposed: 21%, 50%, 75% and 100% (hyperoxia). In each group five animals were randomly induced to diabetes by means of at a dose of 55 mg/kg of streptozotocin (STZ). Results: Seventy two hours after diabetes induction, a significant difference was seen in blood glucose in the experimental groups in comparison with the control. In the experimental groups a significant difference was observed in the concentration of malondialdehyde (MDA) in lung tissue and blood plasma (p<0.05), except the 50% group. In the control group, significant differences in the MDA concentration in plasma and lung tissue were also observed (p<0.05), except the 75% group. The MDA concentration in lung tissue in comparison with the diabetic and non-diabetic groups showed a significant difference in the 21% group; however, no difference was seen in the 75 and 100% groups. Conclusion:In diabetic animals high oxygen concentrations (75 and 100%) do not appear to exert deleterious effects on lipid peroxidation in lung tissue.

Characterization of oxidative stress in animal model of neonatal hypoxia

“…At physiological levels, oxidants play a beneficial role in the body in several vital functions, such as energy production and host defense. Excessive presence of oxidants (ROS) in relation to antioxidants is defined as oxidative stress that results in pathological changes in the body 1 , 7 . Thus, it is interesting to determine the antioxidant status, in individuals under different pathological situations, such as our model of neonatal hypoxia, through different parameters such as: lipid peroxidation, SOD, GSH, among others 8 .…”

“…Compounds that can be modified by the action of free radicals, such as lipids and proteins, are also used as indirect measures of oxidative stress, as well as the enzymatic activities involved in cellular redox balance, such as SOD and CAT. Although GSH is not an enzyme, it acts in the conversion of superoxide radicals into peroxides 1 , 15 . Other biomarkers, called oxidative damage products, can also be measured and the main one is MDA, formed at the end of lipoperoxidation processes 7 .…”

“…At physiological levels, oxidants play a beneficial role in energy production, cell signaling and host defense. In excess, they can lead to pathological consequences for tissue and cell damage, disorders and diseases, resulting from the lack of antioxidant protection systems, or defects in the genes that regulate the antioxidant machines 1 , 2 .…”