Protective Effects Of Ganoderma Lucidum Spore On Subacute Cadmium Nephrotoxicity In Male Rat

Objective: To investigate the protection of Ganoderma lucidum spore(GLS)to the kidney of male rat treated with cadmium for 42 days and explore the possible mechanism.Methods: 50 male SD rats were stratified by weight,and were randomly divided into the control group(C,saline+saline,by gavage),the Cd group [Cd,Cd Cl2(6.5 mg/kg)+saline,by gavage],and 3 treatment groups: GCd L [Cd Cl2(6.5mg/kg)+ GLS(0.1 g/kg),by gavage],GCd M [Cd Cl2(6.5 mg/kg)+(0.5 g/kg),by gavage],GCd H [Cd Cl2(6.5 mg/kg)+(1.0 g/kg),by gavage],10 in each group,and all were treated for 42 days.Rats were weighed regularly,and their common behavior were observed.At the completion of the experiment,rats were sacrificed by anesthetization,blood was sampled from abdominal aorta to biochemical tests,and kidney was stored in-80℃ refrigerator.The cadmium content of Kidney and Mitochondria,microsome,and cytoplasm were tested by atomicabsorption spectrophotometry,and kidney were examined by histopathology.Rate of apoptosis and cell cycle in kidney were measured by the Flow Cytometry.p53,Gadd45α,Bax,Bcl-2 and Caspase-3 gene expression were analized by fluorescence-based real-time PCR.Results: Compared with Cd group,creatinine,urea,uric acid,serum cystatinc were reduced in synchronization group,and creatinine in GCd M,GCd H were significantly reduced(P<0.05).The cadmium contents in Mitochondria,microsome,and cytoplasm reduced after receiving GLS(P<0.05).Kidney histopathological observation showed severe engorgement of the interstitium,tubular dilatation,tubular atrophy,karyolysis of tubular epithelial cells in kidneys of Cd group rats than that of GLS treated rat,and the protective effect of high dose GLS showed better than medium one.In Cd group,the rate of kidney apoptosis was significantly higher than that of the control group,and the rate of kidney cell apoptosis in were significantly reduced after GLS application(P<0.05),and the rate of GCdH was lower the that of GCd L(P<0.05).Compared with Cd group,the renal cells G2/M phase was higher than control group(P<0.05).After GLS intervention,the renal cells G2/M phase was decreased in each pretreatment group(P<0.05).Rats were exposed to cadmium,the gene expression of p53,Gadd45α,Bax,caspase-3 was higher than control group.The above genes expression were significantly reduced in GLS pretreatment group(P<0.05),with the exception of higher Bcl-2 gene expression(P<0.05).Conclusions: GLS can play a protective role to Cd affected rat kidney,and the underlying mechanism may be related to reduce the rate of apoptosis and DNA damage and the expression of genes that are critical for the control of apoptosis.