Ageing of kidneys is a clinical health issue of the society. Age-related renal insufficiency has important implications due to impaired redox homeostasis. We examined protein, DNA and lipid oxidation biomarkers as well as protein-bound sialic acid (SA) in the kidney tissues of D-galactose induced ageing rats, naturally aged rats and their corresponding young control group. Intraperitoneal injection of D-galactose (60 mg/kg/day) for 6 weeks to young male Sprague-Dawley rats (20-week-old) was used to establish mimetic ageing model. In this study, we investigated the levels of protein carbonyl groups (PCO), various thiol fractions such as total thiol groups (T-SH), protein (P-SH) and non-protein thiol groups (NP-SH), lipid oxidation parameters such as lipid hydroperoxides (LHP) and malondialdehyde (MDA), SA and 8-hydroxy-2'deoxyguanosine (8-OHdG) parameters for comparison of naturally aged, induced aged and young rats. In D-galactose induced aged group, PCO, LHP, MDA, and 8-OHdG concentrations were significantly higher than young control group, whereas T-SH, P-SH levels were significantly lower than the young rats. In addition, NP-SH and SA concentrations were similar between the mimetic ageing and young control groups. In naturally ageing rats, PCO and MDA levels were significantly higher, whereas T-SH, P-SH, NP-SH concentrations were low compared to young controls. On the other hand, SA and 8-OHdG levels were not different between the naturally ageing group and the young control group. Our results demonstrated that the rats in the mimetic ageing group, have significant similarities with the naturally aged rats in terms of impaired redox homeostasis and can be used as a reliable animal model for renal ageing.

Background: Diabetes mellitus (DM) causes debilitating complications and, as a result, diabetics frequently require intensive care. Although lungs are not thought to be affected primarily by DM, an increasing number of studies indicate physiological and structural abnormalities in diabetic lungs. Objectives: Pyrrolidine dithiocarbamate (PDTC) is a metal chelator and a potent inhibitor of NF-ĸB. Keeping in mind that NF-ĸB activation may be crucial in end-organ injury due to DM, we studied the role of PDTC on the inhibition of NF-ĸB activation and its effects on possible lung injury in rats with streptozotocin-induced DM. Methods: 36 Sprague-Dawley rats were allocated into 4 groups: diabetes, diabetes + PDTC, control and control + PDTC. At the end of 10 weeks, rats were sacrificed and their lungs were taken for histopathological and immunohistochemical evaluation [for NF-ĸB (p65) and endothelial nitric oxide (eNOS) immunoreactivities]. Protein carbonyl content (PCC), superoxide dismutase (SOD) and reduced glutathione (GSH) activities were measured. Results: Histopathologically, basal membranes were thickened and there was intense inflammatory reaction in diabetic lungs. However, the PDTC group, in which there were poor positive expressions of eNOS and p65 activity compared to diabetes group, revealed fewer inflammatory changes. PCC levels in diabetic lungs were higher, but SOD and GSH activities were lower. However, measurements of these parameters in the PDTC group and controls gave similar results. Conclusion: Lungs are exposed to changes induced by oxidative stress in diabetes through NF-ĸB activation and PDTC seems to be useful to prevent diabetic lung injury.

Heavy metals are naturally occurring elements on the earth's crust and they are also referred to as trace elements [1]. Some of these metals have found application in many areas of human life, such as agriculture, pharmacy, cosmetics, industry, medicine, etc. Human exploitation of these metals has increased the risk of environmental pollution from them. In view of their toxic properties they can be dangerous to all receiving ecosystems [2]. Sources of heavy metals contamination of aquatic ecosystems can be mines, industrial wastewater, fertilizers, pesticides and also deposition and erosion of the geological matrix [3]. Contamination of water with these pollutants can have

A redox basis of the increased oxidative protein damage and free radical-mediated desialylation have not been fully elucidated in aging. It is well known that the incidence of several liver diseases increase with age. This original research focuses on protein oxidation mechanisms and protein-bound sialic acid levels in liver tissue of the mimetic aging rats. Injection of D-galactose (60 mg/kg/day) for six weeks to male Sprague-Dawley rats (20-week-old) used to establish mimetic aging model. We investigated the tissue levels of various protein oxidation markers such as protein carbonyl groups, suitable advanced oxidation protein products and protein thiol groups. Our study also covered protein-bound sialic acid in liver tissue of D-galactose-induced aging rats. PCO (Protein Carbonyl Groups), P-OOH (Protein Hydroperoxides) and AOPP (Advanced Oxidation Protein Products) levels in aging rats were significantly higher compared to young control groups. On the other hand, P-SH (Protein Thiol Groups) levels were not found to be different between two groups. SA (Sialic Acid) levels in D-galactose-induced aging rats were significantly lower compared to control groups. Our results demonstrated greater susceptibility to hepatic oxidative protein damage and desialylation of hepatocellular proteins in Dgalactose- induced aging rats. These molecular mechanisms may be operative in the many age-related liver diseases, which are pertinent to increased oxidative stress and altered redox homeostasis.