L-Carnitine ameliorates glycerol-induced myoglobinuric acute renal failure in rats.

There is increasing evidence indicating that oxidative stress plays an important role in the pathogenesis of rhabdomyolysis-induced myoglobinuric acute renal failure (ARF). During times of war and natural disasters, myoglobinuric ARF can assume epidemic proportions. Thus, early and effective renoprotective treatments are of utmost importance. It has been shown that L-carnitine, used as a safe and effective nutritional supplement for more than three decades, is effective in preventing renal injury in many renal injury models involving oxidative stress. The present study was performed to investigate the effects of L-carnitine in an experimental model of myoglobinuric ARF. Four groups of rats were employed in this study: group 1 served as a control; group 2 was given glycerol (10 mL/kg, i.m.); group 3 was given glycerol plus L-carnitine (100 mg/kg, i.p.), starting at the same time as the glycerol injection; group 4 was given glycerol plus L-carnitine (100 mg/kg, i.p.), starting 48h before the glycerol injection. After glycerol injections, the i.p. injections of L-carnitine were repeated every 24h for four days. Ninety-six hours after glycerol injections, blood samples and kidney tissues were taken from the anesthetized rats. Urea and creatinine levels in plasma, N-acetyl-beta-D-glucosaminidase activity in urine, and malondialdehyde levels and catalase enzyme activity in kidney tissue were determined. Histopathological changes and iron accumulation in the kidney tissue were evaluated. In this study, glycerol administration led to marked renal oxidative stress, as well as severe functional and morphological renal deterioration. L-carnitine, possibly via its antioxidant properties, ameliorates glycerol-induced myoglobinuric kidney injury.

Experimental myoglobinuric acute renal failure: the effect of vitamin C.

During times of war and natural disasters, rhabdomyolysis-induced myoglobinuric acute renal failure (ARF) can assume epidemic proportions. Free radicals play an important role in the pathogenesis of myoglobinuric ARF. Vitamin C is a major antioxidant, scavenging free radicals. We have not found any studies on the effect of vitamin C on myoglobinuric ARF. Thus, we aimed to investigate the effects of vitamin C on the myoglobinuric ARF formed by glycerol in rats. Three groups of rats were employed in this study. Group 1 served as control, group 2 was given 50% glycerol (10 mL/kg, i.m.), and group 3 was given glycerol plus vitamin C (20 mg/kg, i.p. for four days). Ninety-six hours after glycerol injections, blood samples and kidney tissues were taken from the anesthetized rats. Urea and creatinine levels in plasma; N-acetyl-beta-D-glucosaminidase activity in urine; malondialdehyde levels, superoxide dismutase and catalase enzyme activity in kidney tissue were determined. Histopathological changes and iron accumulation in the kidney tissue were evaluated. In this study, glycerol administration led to marked renal oxidative stress and severe renal functional and morphological deterioration. The treatment of animals with vitamin C partially corrected the renal dysfunction and morphological impairment. In this respect, vitamin C appears to be a promising candidate for the prevention of rhabdomyolysis-induced ARF. Higher dosages of vitamin C than in 20 mg/kg may be beneficial for better functional and morphological recovery in this model ARF.

Levels of superoxide dismutase and malondialdehyde in primary spontaneous pneumothorax.

The aim of the present study is to determine whether patients with primary spontaneous pneumothorax (PSP) are subject to oxidative stress. For this purpose, we measured the activities of red blood cell superoxide dismutase, which is an antioxidant enzyme, and the level of plasma malondialdehyde, which is one of the lipid peroxidation markers, in a group of patients with PSP. The study was carried out with 16 patients with PSP and 24 healthy individuals. The two groups were similar to each other in terms of sex, age and smoking attitudes. Erythrocyte superoxide dismutase activity was found to be significantly lower in patients with PSP than in the control group (p < 0.01). The plasma malondialdehyde levels were significantly high in patients with PSP (p < 0.01). Our results suggest that oxidative stress may contribute to the pathogenesis of PSP.

Elevated serum TNF-alpha levels in normal-weight women with polycystic ovaries or the polycystic ovary syndrome.

OBJECTIVE: To compare the serum tumor necrosis factor-alpha (TNF-alpha) levels in nonobese women with those in women with polycystic ovaries (PCO) and polycystic ovary syndrome (PCOS) and healthy controls. STUDY DESIGN: Twenty-one sonographically and biochemically diagnosed women with PCOS, 19 with PCO and 14 healthy women were recruited for the study. Serum TNF-alpha levels were measured in all three groups. Insulin and glucose serum concentrations were analyzed before and after a 75-g oral glucose tolerance test in all samples. The serum TNF-alpha, glucose and insulin levels were compared in PCOS, PCO and controls. RESULTS: Serum TNF-alpha levels were similar in the PCOS and PCO groups (23.67 +/- 5.58 and 13.58 +/- 1.34 pg/mL, respectively) and significantly higher than in the control group. Serum TNF-alpha levels did not significantly correlated with body mass index, serum total testosterone, LH, DHEAS, fasting glucose and fasting insulin levels or glucose and insulin area under the curve values in the three groups. CONCLUSION: We found similar TNF-alpha levels in patients with PCOS and with PCO; however, there was no correlation between the TNF-alpha and insulin, glucose and androgen levels in the study.