Abstract:
Objective To observe the effects of curcumin on nephrotoxicity of rats induced by sub-chronic cadmium exposure, and provide experimental evidence for the mechanism of cadmium poisoning and its prevention and treatment.
Methods Forty-eight Wistar rats were randomly divided into four groups by body weight:control group (saline), low-dose cadmium chloride group (3 μmol/kg cadmium chloride), high-dose cadmium chloride group (6 μmol/kg), and curcumin intervention group (6 μmol/kg). Exposure started from Monday to Friday by daily intraperitoneal injection and lasted for six weeks. Two hours before the exposure on every Monday, Wednesday, and Friday, the rats in the control, low-dose, and high-dose groups were injected subcutaneously with normal saline, while the rats in the intervention group was injected subcutaneously with 50 mg/kg curcumin, all lasted for six weeks. After the last injection of cadmium chloride, the following indicators were determined:24-hour urine lactate dehydrogenase (LDH), alkaline phosphatase (ALP), N-acetyl-beta-D-glucosaminidase (NAG), urine protein, serum urea nitrogen (BUN), glutathione (GSH), malonydialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and renal cells reactive oxygen species (ROS) and apoptosis.
Results Compared with the control group, the increased body weights in the cadmium administered rats were reduced. In the high-dose cadmium chloride group, the contents of urine protein(2.51±0.57) g/g creatinine and BUN(32.82± 4.99) mmol/L, the activities of LDH(1180.54±293.55) U/g creatinine, ALP(211.53±46.39) U/g creatinine, and NAG(104.94± 18.58) U/g creatinine, the content of MDA(4.59±0.67) μmol/g protein, ROS(527.50±60.12) median fluorescence intensity and the apoptosis rate of renal samples(41.88±4.10)% were increased, while the content of GSH(26.75±6.92) μmol/g protein and the activities of SOD(35.65±6.27) U/mg protein and GSH-Px(62.91±20.50) U/mg protein were decreased. Compared with the highdose cadmium chloride group, the curcumin intervention group showed varying degrees of antagonistic activity against nephrotoxicity of cadmium.
Conclusion Sub-chronic administration of cadmium could result in renal damage, and curcumin might present a potential antagonistic effect on the renal damage induced by cadmium.