Panax Notoginseng Saponins Attenuates Cisplatin Induced Nephrotoxicity Via The Mitochondrial Pathway Of Apoptosis And Autophagy

Objective:To investigate the effects of panax nonstaining saponins (PNS) on the apoptosis and autophagy of renal cell induced by cisplatin via the path of mitochondrion, for providing theoretical treatment of kidney damage induced by cisplatin in clinical.Methods:1.Established the model of cisplatin-induced kidney injury in rats: Male Sprague-Dawley(SD) rats were randomly divided into control group, cisplatin model group and the cisplatin+PNS group; At day 1,4 and 8 after exposure to cisplatin, animals were sacrificed to determine the serum creatinine (Scr), blood urea nitrogen(BUN) and the N-acetyl-(3-D-Glucosaminidase(NAG) concentrations in urine. HE-staining was employed to observe renal pathologies changes. Transmission electron microscopy(TEM) was employed to observe the mitochondria of the rats’injured kidney region.2.Impact of PNS on apoptosis of cisplatin induced kidney injury: Transmission electron microscopy (TEM) was employed to observe the mitochondria of the rats injured kidney region. TUNEL staining was employed to detect the distribution of apoptotic cells. Immunnohistochemistry was used to detect Bax and Caspases9 expression, and expression of Bcl-2 protein was detected by Western blot.3.Impact of PNS on autophagy of cisplatin induced kidney injury: Transmission electron microscopy (TEM) was employed to observe the mitochondria of the rat injured kidney region and the formation of autophagic vacuoles. The expression of HIF-1 was detected by immunohistochemistry. The expressions of microtubule-associated protein-1 light chain 3(LC3), autophagy related gene (Atg) 5, Beclin-1 and BNIP3 in rat renal tissue were detected using western blotting.Results:1.Established the model of cisplatin-induced kidney injury in rats: At day 1,4 and 8 after exposure to cisplatin, compared with the control group, contents of BUN, Scrum Cr and urinary NAG levels of rat in the cisplatin model group were increased(P< 0.01), some mitochondria of the epithelial cells of renal tubules injury seriously. Compared with the cisplatin model group, the levels of serum Cr, BUN and NAG in urine were significantly decreased(P< 0.01) in the cisplatin+PNS group, some mitochondria of the epithelial cells of renal tubules and the damage of kidney tissues were significantly improved.2.Impact of PNS on apoptosis of cisplatin induced kidney injury: Compared with the control group, the apoptosis rate of kidney cell was significantly increased(P<0.01) in the cisplatin model group, the expression of Bax, Caspase9 and Bcl-2 protein was significantly increased(P<0.01) in the cisplatin model group; Compared with the cisplatin model group, the apotosis rate of kidney cell and the expression of Bax, Caspase9 protein were decreased significantly(P<0.01), but the expression of Bcl-2 was significantly increased(P < 0.01) in the cisplatin+PNS group.3.Impact of PNS on autophagy of cisplatin induced kidney injury:The rats exposed to cisplatin after 24h, compared with the control group, autophagosome was detected by TEM increased, the expression of LC3, HIF-1, Beclinl, BNIP3, Atg5 proteins of kidney tissue were significantly increased(P<0.01) in the cisplatin model group. Compared with the cisplatin model group, HIF-1, Beclinl, BNIP3, Atg5 proteins of kidney tissue were significantly increased(P<0.01) in the cisplatin+PNS group.Conclusion:1.PNS significantly protect against cisplatin-induced nephrotoxicity, as evidenced by the decrease in concentration of blood BUN, Scr and urinary NAG, as well as the attenuation of renal histopathological damage. The model of cisplatin-induced kidney damage was made successfully.2.PNS may through increase the expression of Bcl-2 protein and decrease the expression of Bax and caspase-9 proteins to regulate cell apoptosis, which may play a protective role in cisplatin nephritic damage.3.In conclusion, the protective effect of PNS on cisplatin-induced nephrotoxicity was mainly due to its ability to enhancing the mitochondrial autophagy of renal tissue via the HIF-1α/BNIP3/Beclinel/Atg5 pathway.