Adriamiycine induced nephrotic syndrome in rats cyclosporine a and mycophenolate mofetil combination therapy

Nephrotic syndrome is one of the commonest nephrologic problems in children, a heading cause of chronic renal failure. Although many therapeutic options have been tried, a net effective treatment for steroid resistant nephrotic syndrome has not been found yet. Besides, serious side effects of available drugs trigger the need for search of new treatment options. Though cyclosporine a is an effective immunesupressive drug in the treatment of nephrotic syndrome, various side effects and frequent relaps rate after cessation of the treatment limit its use. Its most serious side effect is nephrotoxicity which is the most important factor limiting its use. Recent studies has pointed to somehow effectiveness in restricting proteinuria, also mycophenolate mofetil (MMF) less side effects. As there is not an enough effective treatment for steroid resistant nephrotic syndrome, new therapeutic options and combined therapies are now being discussed. In this study, we aimed to decrease side effects of cyclosporine a by decreasing its dosage and increase its effectiveness by adding MMF to the treatment. Rats with nephrotic syndrome caused by adriamycine were divided into groups according to different treatment modalities which were cyclosporin a, MMF, low – dose cyclosporine a and combined therapy (low – dose CsA and MMF). Efficacy and side effects of these treatments were evaluated biochemically and pathologically. 50 Wistar albino type adult male rats, being 10 rats in each group, were included in the study. Study groups were; Group A: Rats with nephrotic syndrome caused by adriamycine who were not given any treatment. Group B: Rats with nephrotic syndrome caused by adriamycine who were given 25 mg / kg cyclosporine a. Group C: Rats with nephrotic syndrome caused by adriamycine who were given 20 mg / kg / day mycophenolate mofetil. Group D: Rats with nephrotic syndrome caused by adriamycine who were given low – dose cyclosporine a (10 mg / kg / day). Group E: Rats with nephrotic syndrome caused by adriamycine who were given low – dose cyclosporine a plus mycophenolate mofetil (combined regimen). Treatments were initiated on the 22th day after the second injection of adriamycine. Body weights of rats were measured once a week, blood pressures were measured once a month under minimal dose ether anesthesia. Blood and 24 hour urine samples were collected on 0th week (before injection of adriamycine), 4th and 8th weeks after injection of adriamycine. These samples were preserved at – 70 degree C till the end of the study. Blood samples were analysed for serum total protein, albumin, creatinine, total cholesterol, triglycerides, total oxidant status (TOS) and total anti – oxidant status (TAS). 24 hour urine samples were analysed for total protein and creatinine. Creatinine clearance, urine protein / creatinine ratio, 24 hour urine protein and oxidative stress index were calculated. At the end of the study, all the rats were sacrificed. Their kidneys were removed out and weighed. Pathology samples were examined after treating with hematoxylin eosin, masson – trichrome, TGF – Beta, osteopontine dyes, then GSI (glomerulosclerotic index), IFS (interstitial fibrosis score), total injury score (TIS) were calculated. Interstitium for TGF – Beta and tubules for OPN (osteopontine) were examined. This study were designed to last for 16 weeks; however it was cessated on the 9th week due to some rat waste. A total of 12 rats (5 from both cyclosporine a and combined regimen groups, 2 from low – dose cyclosporine a group) died. On the 4th week, hypoalbuminemia and hypoproteinemia together with hyperlipidemia were detected. However, there was not an increase in proteinuria on the 4th week. On the 8th week, urine protein / creatinine ratio was found to be significantly lower in MMF and low – dose cyclosporine groups when compared to 4th week. Serum total protein and albumin levels were preserved better in combined regimen group compared to other groups. Control of hyperlipidemia was also easier in combined regimen group. Best results came from low – dose cyclosporine a and combined regimen groups in means of oxidative injury. There was not a statistically significant difference between serum creatinine clearances of all groups. Serum creatinine level was higher in cyclosporine a group compared to the other groups. In histopathologic evaluation, GSI and TIS were found to be significantly higher in cyclosporine a group compared to the other groups. IFS was significantly higher in MMF group compared to combined regimen group. TGF – Beta was significantly higher in MMF group compared to cyclosporine a group. OPN was significantly lower in cyclosporine a group compared to the other groups. In conclusion, MMF yields a similar effectivity with low – dose cyclosporine a in preserving serum protein and creatinine while low – dose cyclosporine a is limiting oxidative stress and combined therapy is controlling hyperlipidemia. This study has shown that cyclosporine a can cause glomerulosclerosis and renal injury without increasing the release of OPN and TGF – Beta which is opposite to literature. Also, low – dose cyclosporine a and combined therapy were found to be more effective in controlling both systolic and diastolic blood pressures.