The Protective Effect Of Cardamonin On Oxidative Damage Of Spem And Its Mechanism In Vitro

ObjectivePhysiological level of ROS is necessary to maintain male reproductive physiology function, but excessive ROS is easy to cause oxidative stress damage. P38 MAPK(mitogen- activated protein kinase, MAPK), a kind of ser/thr protein kinase and widespread in the mammals, plays an important role for apoptosis, cytokine production, transcriptional regulation and recognize the cytoskeleton. Studies have shown that Cardamonin can significantly inhibit P38 MAPK phosphorylation. The present study is designed to examine whether CAR can protect sperm from oxidative damage caused by LPS, and explore the possible mechanism, in order to find a safe and effective drug to treat male infertility. Methods 1 Experimental materialSpecimen semen of human 2 Grouping and drug deliverySperm suspensions were divided into six groups: Control group, Earle’s medium; LPS group, LPS; LPS+CAR(0.5 μM) group; LPS+CAR(1 μM) group; LPS+CAR(2 μM) group; LPS+Vic(2 μM) group. LPS final concentration: 1 μg·m L-1. The sperm samples were incubated with atmosphere of 5% CO2 at 37 °C for 15 h. 3 Measurements and methodology 3.1 The total vivability of sperm was meassured by microscope. 3.2 The HOS of sperm was measured by microscope. 3.3 The acrosome integrity of sperm was measured by fluorescence microscope. 3.4 The DFI of sperm was measured by fluorescence microscope. 3.5 The content of ROS was measured by NBT. 3.6 The content of MDA was measured by TBA. 3.7 The activity of SOD was measured by WST. 3.8 The protein expression of P38 MAPK, p-P38 MAPK, were performed byWestern-blot. Results 1 Sperm motility was significantly improved by CAR in oxidative damageinduced by LPS, and CAR also reduced the apoptosis and DFI of sperm(P<0.01). CAR can significantly improve the rate of HOS and acrosomeintegrity(P<0.01), and the effect is stronger in a high dose of CAR treatment. 2 CAR not only obviously reduced the content of ROS and MDA, but alsoincreased the SOD activity(P<0.05), and this effect is also stronger atexposure with high dose of CAR. 3 CAR can inhibit the expression of p-P38 MAPK caused by LPS in adose-dependent manner(P <0.05), however, CAR had no significant effect onthe total protein expression of P38 MAPK. 4 The protein expression of p-P38 MAPK and ROS levels were significantlyhigher in LPS group compared with control group(P<0.05), and the proteinexpression of p-P38 MAPK was positively correlated with the content of ROS. ConclusionsCAR can protect the oxidative damage of sperm induced by increasing SODactivity and reducing the content of ROS and MDA, which is possible involved inphosphyration inhibition of P38 MAPK in a dose-dependent manner.