The activities of acid DNase and 5'nucleotidase in erosive reflux esophagitis and Barrett's epithelium.

BACKGROUND/AIMS: The study examines the relationship between activity of acid DNase and 5'nucleotidase (5'NT) and histological changes in reflux esophagitis. METHODOLOGY: Thirty-three patients were examined, 15 of whom with mild esophagitis, 12 with severe esophagitis and 6 with Barrett's epithelium. Patients were classified into 3 groups, according to Ismail-Beigi histological criteria: mild esophagitis group (ME); severe esophagitis group (SE); Barrett's esophagitis group (BE). DNase and 5'NT levels were measured biochemically both in healthy and injured tissue samples. RESULTS: Difference of acid DNase and 5'NT activity in healthy tissue versus injured tissue samples was the lowest in ME group: 0.55±4.47 U/g for acid DNase and 11.56±37.11 U/g for 5'NT, the difference increased to 4.43±1.64 U/g for acid DNase and 105.57±54.11 U/g for 5'NT in the SE group, while 6.07±2.92 U/g for acid DNase and 109.83±14.02 U/g for 5'NT as the highest levels were measured in the BE group. Difference in BE group is statistically significantly higher (p <0.05) compared to the ME group, confirmed by ANOVA with Dunnett's post hoc test. CONCLUSIONS: The study shows significant decrease of apotosis level that is detectable even before metaplasia was morphologically defined.

Protective effects of glutathione and lipoic acid against cadmium-induced oxidative stress in rat's kidney.

Cadmium is a widespread, toxic industrial pollutant. The proximal tubule of the mammalian kidney is a major target of Cd-induced toxicity. We analyzed the effects of cadmium exposure on the model system of experimental animals, the thiobarbituric acid (TBA)-reactive substance (TBARS) level, and the activity of xanthine oxidase (XO) and catalase in kidney of rats, with and without glutathione and lipoic acid (LA). The experimental animals were classified into six groups, regarding cadmium, glutathione, and LA intake. The concentration of TBARSs in the homogenate was determined by spectrophotometric method according to Nabavi et al. The specific activity of XO was determined spectrophotometrically by the method of Aygul et al. Catalase activity in tissues was determined by spectrophotometric method according to Nabavi et al. The increased level of TBARS and the increased activity of XO in kidney tissue in cadmium poisoning are statistically significant compared to control (p < 0.001). Glutathione and LA applied along with cadmium lowered TBARS concentration and reduced XO activity (p < 0.001). Catalase activity in the kidney tissue was increased in the group, which was administered cadmium (p < 0.001). In conclusion, glutathione and LA, as physiological antioxidants applied with cadmium, have reduced the level of lipid peroxide and the activity of XO, and can be used as protectors in conditions of cadmium poisoning.