Beneficial effects of mate-herb, Ilex paraguariensis St. Hil. against potassium dichromate-induced oxidative stress and nephrotoxicity

Chimarrão is a typical beverage made from the infusion of dried and ground leaves and stems of Ilex paraguariensis (popularly known as Yerba mate or mate herb) which is widely consumed in parts of South America. The aim of this study was to examine the effects of the chimarrão against nephrotoxicity and oxidative stress induced by the potassium dichromate (PD) salt in male Wistar rats. The experiment lasted 17 days, and in the first 15 days animals ingested a chimarrão infusion or control drinking water and then submitted to an intraperitoneal injection (15 mg/kg) of PD (or saline solution) and euthanized after 48 hr at which time animals still received infusion or drinking water. Blood plasma and 24 hr-urine samples were collected to measure creatinine levels as an estimate of glomerular filtration rate (GFR). Concomitantly oxidative stress was determined in the kidneys as evidenced by levels of carbonyl groups, malondialdehyde (MDA) and antioxidant capacity against peroxyl radicals. Potassium dichromate induced oxidative stress in the kidneys and reduced GFR. Treatment with chimarrão during the 15 days prior to PD injection reduced PD salt-mediated oxidative stress. Further, treatment with post-injection chimarrão to PD-administered rats improved the GFR. Our findings support that the use of the chimarrão beverage may be considered as an important nephroprotective substance.