Bioaccumulation and distribution of Pb, Ni, Zn and Fe in stinging nettle (Urtica dioica) tissues and heavy metal-contamination assessment in the industrial zone of smelter Ferronikeli (Drenas-Kosovo).

Here, we determined the concentrations of Pb, Ni, Zn and Fe in the soil and in vegetative organs of stinging nettle (Urtica dioica) collected from the banks of the Drenica River in the vicinity of the Ferronikeli smelter. The results were compared with samples collected from the banks 20 km (Shalë village) upriver. In addition, the bioaccumulation factor (BCF) and translocation factor (TF) were determined. Meanwhile, to evaluate the level of pollution in the study area was used the contamination factor (CF), potential ecological risk factor (Eri) and the potential ecological risk index (RI). The order of heavy metals according to their concentration in the soil samples at both sampling sites was as follows: Fe > Ni > Zn > Pb. Concentrations in excess of the limits allowed for soils in the samples collected in the vicinity of the smelter were recorded for Pb (173.13 mg kg-1), Zn (1217.48 mg kg-1), and Ni (1443.93 mg kg-1), while at the control site, Zn (270.82 mg kg-1) and Ni (375.47 mg kg-1) were found in excess concentrations. But lead (Pb) level was under allowed limit. The data showed that the stinging nettle is not a hyperaccumulator because BCF < 1 at both sites for all metals under study. Furthermore, analysis of the translocation factor (TFsteam/root) showed that at low of heavy metal concentrations, their mobility was higher (TF > 1). The lowest mobility (TF < 1) was observed at site I (Poklek), where the concentration of heavy metals was higher, except for Fe. The opposite was shown for mobility of metals from stems to leaves (TFleave/steam). The evaluation of CF showed that the area near the Ferronikeli smelter had low degree of Pb, moderate degree of Zn and considerable degree of Ni contamination. The values of RI indicate low potential ecological risk index.

Increased protein oxidation and loss of protein-bound sialic acid in hepatic tissues of D-galactose induced aged rats.

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.

Comparison of oxidative stress biomarkers in renal tissues of D-galactose induced, naturally aged and young rats.

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.

Protective effect of the nuclear factor kappa B inhibitor pyrrolidine dithiocarbamate in lung injury in rats with streptozotocin-induced diabetes.

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-kappaB. Keeping in mind that NF-kappaB activation may be crucial in end-organ injury due to DM, we studied the role of PDTC on the inhibition of NF-kappaB 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-kappaB (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-kappaB activation and PDTC seems to be useful to prevent diabetic lung injury.