No abstract

Hexavalent chromium Cr (VI) causes various toxic and carcinogenic effects. The main carcinogenic effect is observed in the pulmonary system through inhalation route. Reduction of Cr (VI) to Cr (V, IV, and III) reactive intermediates within the cells by intracellular reducing agents such as glutathione is an important event leading to oxidative stress and oxidative DNA damage. This study evaluated the effects of intraperitoneal administration of Cr (VI) and GSH on total oxidant status (TOS), total antioxidant capacity (TAC), oxidative stress index, and oxidative DNA damage by evaluating the level of 8-hydroxy-2́-deoxyguanosine (8-OHdG) in Swiss-Albino mice. Seventy two mice were divided into 6 groups and treated intraperitoneally as follow: control (saline), group GSH (30 mg/kg GSH) groups of Cr-20 (20 mg/kg, KCrO), Cr-30 (30 mg/kg KCrO), Cr-20 + GSH (20 mg/kg KCrO + 30 mg/kg GSH), Cr-30 + GSH (30 mg/kg KCrO + 30 mg/kg GSH). Total oxidant capacities of Cr-20 and Cr-30 were increased compared to control, Cr-20 + GSH, and Cr-30 + GSH. TOS levels in Cr-20 + GSH and Cr-30 + GSH were lower than in Cr-20 and Cr-30. No difference in TAC was observed among the groups. 8-Hydroxy-2́-deoxyguanosine levels were increased in groups Cr-20 and Cr-30 compared with control and groups Cr-20 + GSH and Cr-30 + GSH. No difference was determined in 8-OHdG levels among control, groups GSH, Cr-20 + GSH and Cr-30 + GSH. Results indicate that Cr (VI) given i.p. route causes increased oxidative stress and oxidative DNA damage in the blood of Swiss-Albino mice. Administration of GSH via i.p. route protects from oxidative stress and DNA damage.

Abstract. The aim of this study was to investigate the effects of boric acid (BA) and borax (BX) on live weight and obesity associated molecules including leptin, L-carnitine, insulin-like growth factor 1 (IGF-I), and heat shock proteins 70 (HSP70) in rats fed with high-fat diet. A total of 60 rats were equally allocated as ND (normal diet), HF (high-fat diet), HF+BA, HF+BX, ND+BX, ND+BA. Body weight increases in HF+BA (85 g) and HF+BX (86 g) were significantly lower (p<0.05) compared to HF group (126 g). Boron treatment decreased serum L-carnitine level in high-fat diet (HF+BA 11.12 mg/L, HF+BX 10.51 mg/L, p<0.05) compared to HF group (15.57 mg/L), while no change was observed in groups ND+BA (7.55 mg/L) and ND+BX (7.57 mg/L) compared to group ND (8.29 mg/L). Neither BA nor BX supplementation in ND and HF groups altered the serum levels of HSP70 and leptin. BA and BX supplementation in rats fed HF resulted in a significant reduction in live weight. Boron compounds altered L-carnitine and IGF-1 levels in rats. These results indicate that boron compounds are beneficial in the treatment of obesity as well as in the prevention of high-fat diet-induced weight increase. Alterations in serum L-carnitine and IGF-1 levels in boron treated rats also indicate possible role of boron compounds in energy metabolism in response to high fat diet.

Free radicals, which are formed as a consequence of endogenic and exogenic factors in cells, that cause oxidative stress in living organisms can be neutralized through catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), A, E, C vitamins, glutathione, ubiquinone, and flavonoids. The aim of this study is to investigate the effect of trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), a type of vitamin E, on rabbits regarding the total oxidant and antioxidant capacity (TOC, TAC) levels together with the NO levels. In this study, 0.5 ml physiological saline and 1 µmol kg -1 trolox were given respectively to control and experiment rabbits via intraperitoneal (i.p.) route, Plasmas of blood samples, which were obtained in the 1 st , 3 rd , and 6 th hours following injection, were separated and stored at -20 o C until to be analyzed. Plasma TOC, TAC and NO levels were determined spectrophotometrically. When the TOC, TAC, NO levels and OSI values of rabbits that were given trolox were compared to those of the control group, statistically, it was observed that the NO levels were high (p< 0,01) in the 1 st , 3 rd , and 6 th hours; however, there was no alteration in their TAC, TOC levels and OSI values. As a result, it was concluded that trolox given as a single dose to healthy rabbits did not affect TAC TOC levels and OSI value, but the increasing levels of NO might be due to trolox's increasing activity of eNOS.

Endotoxin molecules in lipopolysaccharides are among most important molecules that initiate a cascade of events in sepsis/ endotoxemia. Lipopolysaccharide exposure may result in strong immune responses, disrupt the intracellular oxidant/antioxidant balance, and cause excessive reactive oxygen species generation. The purpose of the study was to examine if reduced glutathione (GSH) has a protective role against lipopolysaccharides. The effects of lipopolysaccharide (LPS) or GSH alone or in combination on the levels of the plasma antioxidant system, NO, and liver HSP70 were investigated. A total of 100 Swiss albino mice were divided into 4 groups as Group I (control), Group II (20 µg/kg LPS), Group III (10 mg/kg GSH), and Group IV (20 µg/kg LPS + 10 mg/kg GSH). Blood and liver samples both pre-and post-LPS and/or GSH injections after 1, 3, and 6 h were collected. Total antioxidant capacity was demonstrated with a reduction in response to lipopolysaccharide. Total oxidant capacity was higher after the injection of lipopolysaccharide alone or in combination with GSH. NO levels were elevated in response to lipopolysaccharide. The liver HSP70 level was determined to be higher in the lipopolysaccharide-treated group. These results indicate that exogenously administered GSH may have regulatory effects on liver HSP70 and plasma NO levels, and GSH treatment might have beneficial effects on antioxidant status by inhibiting the increase of oxidant molecules in endotoxemia-induced mice.