may be ” attributed to intrinsic and extrinsic factors such as toxin exposures and Varlitinib web oxidative stress. Thus, we assessed the oxidative stress and apoptotic features in sperm cells in the present study to further investigate the effects of HBs exposure on sperm membrane integrity and functions. Results ROS levels in sperm cells exposed to HBs ROS levels were measured by flow cytometry using a 29,79dichlorodihydrofluorescein diacetate fluorescent probe. The results are shown in 2 Effects of HBs on Sperm Functions pretreated with N-Acetylcysteine also markedly declined . In sperm cells, HBs exposure increased ROS generation in a dose-dependent manner. Effects of HBs on MDA levels and TAC activity in sperm cells Aldetect lipid peroxidation assay and ferric reducing ability of plasma assay were performed to determine the relationship between HBs exposure and lipid peroxidation, and total antioxidant capacity in sperm cells, respectively. As shown in Externalization of PS in sperm cells induced by HBs The apoptosis-inducing effects of HBs were assessed by flowcytomeric analysis using double staining with annexin V and PI. As seen in HBs induces the activation of caspases-3, -8,- 9 in sperm cells Apoptosis is dependent on the activation of a group of proteolytic enzymes called caspases. A possible link between HBs exposure and caspases-3, -8 and -9 activations in sperm cells was investigated to determine whether HBs 
exposure can cause apoptosis. The sperm cells in the test and control groups were labeled with 1 ml of FITC-DEVD-FMK, FITC-IETD-FMK and FITC-LEHD-FMK for 1 h, respectively followed by washing and analysis by flow cytometry. The results showed in Effects 17622149” of HBs exposure on oxidative DNA damage in sperm cells The effects of HBs exposure on oxidative DNA damage in sperm cells in the control and the test groups were assessed by flow-cytomeric analysis using TUNEL assay. The results are shown in Discussion HBV DNA presented in sperm cells was first addressed by French scientists who proposed that HBV may be a cause of male infertility by damaging spermatozoa. Subsequently, it was reported that in the male genital tract, viral infections could lead to an oxidative stress by spermatozoa and leukocytes including neutrophils and macrophages and a lack of antioxidant protection. Although viral infection can affect a man’s fertility, however up to now, only scant information is available on the influence of HBV infection on the sperm function. Effects of HBs on Sperm Functions HBs exposure induced oxidative stress in sperm cell Successful fertilization requires a sperm plasma membrane with normal integrity and functions. The numerous functions of the membrane are related to cell metabolism, for maintaining sperm motility, capacitation, acrosome reaction and sperm-oocyte interactions. It has been documented that ROS plays a key role in inducing sperm damage. In the present study, a significant increase in ROS positive cells was observed after 3 h exposure to 25 mg/ml of HBs when compared with control. Conversely, the average rates of ROS positive cells significantly reduced when sperm cells were pretreated with HBs monoclonal antibody or the ROS scavenger NAC, respectively. These data provided solid evidences that HBs exposure was able to increase ROS production in sperm cells. Furthermore, our results revealed that the exposure of sperm cells to HBs caused a dosedependent ROS generation. In the previous study, however, Zhou et al reported that t