Apigenin (AP) as a plant flavonoid is found to attenuate acrylonitrile (ACN) toxicity by reducing ROS production and inhibiting apoptosis. Therefore, the present study aimed to evaluate the role of AP on ACN-induced inflammation and apoptosis in germ cells and whether it is through the NF-κB signaling pathway. AP increased the concentrations of lactate dehydrogenase isozyme (LDH) and sorbitol dehydrogenase (SDH), while the concentrations of interleukin β (IL-1β), tumor-necrosis factor-α (TNF-α), and interleukin-6 (IL-6) were significantly reduced. AP could downregulate the expression of the nuclear factor of kappa B (NF-κB) and inhibit phosphorylation of the inhibitory κBα (IκBα). Cleaved caspase-3 was also upregulated by AP, and the apoptotic were less than those in the ACN group. These results suggest that AP might improve maturation and energy metabolism of testes, inhibit NF-κB activation. Then AP could further downregulate NF-κB signal and inhibit the germ cell apoptosis and reduce inflammatory caused by ACN.

In order to study the effects of acrylonitrile (ACN)-induced oxidative damage on endoplasmic reticulum stress (ERS) signaling pathways in rat liver, 50 healthy adult male SD rats were randomly divided into 5 groups, 10 rats in each group, according to the body weight. The rats' groups were treated with 0, 12.5, 25, 50.0 mg·kg-1 ACN via gavage, respectively. NAC group were treated by intragastric administration of 300.0 mg·kg-1 NAC after 30 min of reperfusion 50.0 mg·kg-1 ACN, 1 time per day, 6 days per week for 13 weeks. The levels of GSH and MDA, the activity of SOD, GSH-Px, CAT in liver tissue were measured by spectrophotometry method. The mRNA and protein expressing levels of ERS-related GRP78, CHOP and caspase-12 were detected by RT-PCR and West-ern Blot. The results showed that the levels of GSH in low and middle ACN group were significantly decreased compared to control group. The activity of GSH-Px and SOD, the levels of MDA in low dose group was signifi-cantly increased compared to control group. CAT activity in middle and high dose groups were significantly de-creased in comparison with the control group. Compared with high ACN group, GSH levels was significantly in-creased in NAC intervention group, and also MDA levels and SOD activity were significantly decreased. GRP78, CHOP and caspase-12 in high ACN group showed significant higher mRNA levels than that in the control group. The expression of CHOP and caspase-12 mRNA in NAC group were significantly lower than that in high ACN group. Western Blot showed that the expression levels of GRP78, CHOP and caspase-12 protein in high ACN group were significantly higher than that in control group. The expression levels of GRP78, CHOP, and caspase-12 protein in NAC group were lower than that in high ACN group. Our study indicated that exposure to ACN could induce oxidative damage on rats' liver, and then activate ERS signaling pathway. NAC could reduce the degree of oxidative damage and antagonize the ERS signaling pathway. Further study is needed to find the mechanism of this oxidative damage inducted by ACN on ERS signaling pathway.

目的 探讨芹菜素(apigenin,AP)对丙烯腈(acrylonitrile,ACN)致大鼠肝内质网应激(ERS)信号通路的影响.方法 40只雄性SD大鼠随机分为对照组(玉米油)、ACN组(50 mg/kg·bw ACN)、低AP干预组(234 mg/kg·bw AP+ 50 mg/kg·bw ACN)和高AP干预组(468 mg/kg·bw AP+ 50 mg/kg·bw ACN),灌胃量均为5 ml/kg·bw,1次/d,每周6d,共13周.末次染毒结束后,次日处死大鼠.分光光度法测定肝组织中丙二醛(MDA)、谷胱甘肽(GSH)含量和谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活力;RT-PCR检测ERS相关基因GRP78、CHOP和Caspase-12 mRNA表达水平;Westem blot检测ERS相关蛋白GRP78、CHOP和Caspase-12表达水平.结果 ACN组大鼠肝SOD活力、GSH-Px活力和GSH含量均低于对照组,MDA含量高于对照组,差异有统计学意义(P＜0.05);低、高AP干预组大鼠肝SOD活力、GSH含量均高于ACN组,GSH-Px活力低于ACN组,差异有统计学意义(P＜0.05).ACN组大鼠肝组织GRP78、CHOP和Caspase-12 mRNA及蛋白表达水平均高于对照组(P＜0.05).低AP干预组大鼠肝组织GRP78、CHOP和Caspase-12 mRNA相对表达水平均低于ACN组(P＜0.05),差异有统计学意义.高AP干预组大鼠肝组织GRP78和CHOP mRNA相对表达水平均低于ACN组(P＜0.05),GRP78、Caspase-12蛋白表达水平均低于ACN组,差异有统计学意义(P＜0.05).结论 ACN可致大鼠肝氧化损伤,激活ERS信号通路,AP可减轻ACN引起的ERS.

To investigate the effect of acrylonitrile (ACN) -induced oxidative stress on nuclear transcription factor-κB (NF-κB) signaling pathway in rats spleen, 60 specific pathogen free (SPF) grade healthy adult male rats were randomly divided into 5 groups: control group (corn oil), low-, medium-, and high-dose groups (11.5, 23, 46 mg·kg-1 ACN) and NAC groups (46 mg·kg-1 ACN + 300 mg·kg-1 NAC), and were treated once/day, 6 days/week, by intragastric gavage for 4 weeks. The spleen was isolated and weighed. The activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT), the contents of glutathione (GSH), malondialdehyde (MDA) and total antioxidant capacity (T-AOC) in spleen were detected by spectrophotometry. The interleukin 6 (IL-6), interleukin 1β (IL-1β), tumor necrosis factor-α (TNF-α) levels were determined by Elisa.The expressions of NF-κB, IκB and p-IκB were measured using western blotting and the expressions of NF-κB and IκB mRNA were determined by RT-qPCR. The results showed that the splenic wet weight of the rats were significantly decreased in the low-and middle-dose groups compared with the control group (P＜0.05). The splenic coefficient was also significantly decreased in the middle-dose group (P＜0.05). The contents of MDA in the spleen of rats were significantly increased in the medium-and high-dose groups (P ＜ 0. 05) and the activities of SOD and GSH-Px were significantly increased in the high-dose group (P＜0.05). The activity of CAT and the contents of TAOC and GSH were all decreased in the low-dose group, whereas, the CAT activity was increased in the high-dose group (P＜0.05).Meanwhile, the activities of SOD, CAT and GSH-Px and the contents of MDA, GSH and T-AOC were significantly decreased in the NAC group compared with the high-dose group (P＜0.05). Compared with the control group, the contents of IL-1β were decreased in the middle-and high-dose groups, and the levels of TNF-αwere increased significantly in all dose groups (P＜0.05). Compared with the high-dose group, the content of TNF-α was significantly decreased in the NAC group (P＜0.05). Western Blot results showed that the expressions of NF-κB, IκB, and p-IκB were significantly increased in the medium-and high-dose groups compared with the control group (P＜0.05). The expressions of IκB and p-IκB in NAC group was decreased in the high ACN group (P ＜0.05). RT-PCR results showed that the expression of NF-κB mRNA were increased in the low-, medium-and highdose ACN groups compared with the control group (P＜0.05). And the expressions of IκB mRNA were increased in the medium-and high-dose ACN groups compared with the control group (P＜0.05). The expression of NF-κB mRNA was decreased in the NAC group compared with the high-dose group (P＜0.05). Therefore, the present study suggests that subacute exposure to ACN could produce oxidative damage and immune system response in rats 'spleen, and NAC might reduce the degree of injury through antagonism.

Objective To explore the effect of acrylonitrile induced oxidative stress on flagella ultrastructure and sperm quality of rat epididymis.Methods According to the body weight,40 adult specific pathogen free Sprague-Dawley male rats were randomly divided into one control group and three exposed groups (each group of 10).Rats in exposed group were treated with ACN at dose of 12.5,25 and 50 mg/kg respectively once a day for thirteen weeks via gavage.The reactive oxygen species (ROS),methane dicarboxylic aldehyde (MDA),superoxide dismutase(SOD) and mitochondrial membrane potential(MMP) levels in sperm and the quality of sperm were tested.and the ultrastructure of sperm flagella was observed.Result Sperm MMP in 50 mg/kg group was significantly lower than that in the control group and other groups (1.34 ± 0.10)(P ＜ 0.05).The concentration of ROS in 50 mg/kg group was significantly higher than that in the control group and other groups (P ＜ 0.05).SOD activity in treatment groups were statistically significant compared with the control group (P ＜ 0.05).Under the transmission electron microscopy,the outer dense fiber and mitochondria in sperm tails were damaged in 25 and 50 mg/kg groups.Sperm density in 50 mg/kg group was (3.52 ± 0.46) × 106/ml significantly decreased compared with the control group,12.5 mg/kg group and 25 mg/kg group [respectively (5.71 ±0.66) × 106/ml,(4.95 ± 1.33) × 106/ml and (5.99 ± 0.78) × 106/ml] (P ＜ 0.05).Sperm motility rate in 50 and 12.5 mg/kg group was respectively (62.18 ± 3.4) ％ and (66.25 ± 7.23) ％,and the difference had statistically significant compared with the control group (27.77 ± 4.85) ％ (P ＜ 0.05).The rate of "d" grade sperm in 50 and 25 mg/kg group were respectively (40.76 ± 1.47)％ and (37.77 ±3.41)％,that were significantly increased compared with the control group (27.77 ±4.85)％ and 12.5 mg/ kg group(31.77 ±4.85)％ (P ＜0.05).The average path velocity in control group was (18.17 ± 2.24) μm/s,and was significantly higher than it in each treated group (P ＜0.05).Straight-line speed of sperm in 50 mg/kg group was significantly decreased compared with the control group (P ＜ 0.05).ROS concentration and sperm MMP was significantly negatively correlated (r =-0.643,P =0.024).ROS concentration was showed a significant negative correlation with SOD activity (r =-0.713,P =0.009).Sperm activity was showed a significant negative correlation with ROS concentration (r =-0.629,P =0.028).The average path velocity was showed a significant negative correlation with ROS concentration (r =-0.839,P =0.001).The rate of "d" grade sperm was showed a significant positive correlation with ROS concentration (r =0.699,P =0.011).Conclusion ACN could induce increasing ROS levels in sperm,damage the outer dense fiber and mitochondria in sperm tail.These may be the reasons that ACN could decrease the sperm motility,viability and movement speed.

Acrylonitrile (ACN) treatment can induce testicular toxicity in Sprague-Dawley (SD) rats, with the toxicity potentially related to apoptosis, mediated by nuclear factor-κB (NF-κB). The present study investigated the potential role of NF-κB in the induction of apoptosis and testicular toxicity in ACN-treated rats. Adult male SD rats were randomly divided into 3 treatment groups: a control group (corn oil), an ACN group (50 mg/kg) in which ACN was administered by gavage, and an ACN and N-acetylcysteine (ACN+NAC) group. The rats were given NAC (300 mg/kg) 30 min prior to the administration of ACN, and ACN was administered by gavage for 90 days. The ACN treatment markedly increased malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activity in the testis. Glutathione (GSH) was significantly depleted in the ACN groups, and the effects of ACN were blocked by the anti-oxidant NAC. The ACN treatment also increased the expression of NF-κB (p65) and phosphorylated-IκB kinase (IKK)-α/β and decreased the expression of an inhibitor of NF-κB (IκB-α). The pretreatment with NAC significantly inhibited the activation of NF-κB. In addition, the expression of Bax increased after the ACN treatment, and the induction of Bax was abolished by NAC. Taken together, the data suggested that ACN-induced oxidative stress activated the NF-κB signaling pathway, which modulated the expression of Bax and contributed to testicular apoptosis.

This study aimed to investigate the protective effects of apigenin (AP), a flavonoid found in plants, against acrylonitrile (ACN)-induced subchronic sperm and testes injury in rats. Male Sprague-Dawley rats were randomly divided into four groups: a control group (corn oil), an ACN group (ACN 50 mg kg-1), an ACN + AP1 group (ACN + AP 234 mg kg-1), and an ACN + AP2 group (ACN + AP 468 mg kg-1). The ACN + AP group received AP by gavage after treatment with 50 mg kg-1 ACN for 30 min, whereas the rats in the control group were given an equivalent volume of corn oil. The gavage was conducted 6 days per week for 12 weeks. The results showed that AP increased the sperm concentration, motility, and mitochondrial membrane potential (MMP) (P < 0.05), which were reduced by ACN. Conversely, reactive oxygen species (ROS) and malondialdehyde (MDA) were significantly decreased by AP (P < 0.05). AP improved the damage of the ultrastructure of sperm caused by ACN. AP reduced the pathological injuries and spermatogenic cell apoptosis caused by ACN in rat testes. AP also increased glutathione peroxidase activity and decreased MDA content. In conclusion, AP reduces ACN-induced decreasing sperm quality by inhibition of inflammation and oxidative stress.

为探索丙烯腈(acrylonitrile,ACN)诱导的氧化应激对大鼠睾丸NF-κB信号通路的影响,将50只SPF级健康SD雄性大鼠按体重随机分为12.5、25、50 mg·kg-1 ACN染毒组,50 mg·kg-1 ACN+300 mg·kg-1 N-乙酰半胱氨酸(N-acetyleysteine,NAC)干预组(NAC干预组),对照组(给予等体积玉米油),每组10只,灌胃,1次/天,6天/周,共90 d.可见光分光光度法检测睾丸组织中超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)、还原型谷胱甘肽/氧化型谷胱甘肽比值(glutathione/oxidized glutathione,GSH/GSSG)、丙二醛(malondialdehyde,MDA).免疫荧光染色法检测睾丸核因子-κB(nuclear factor κB,NF-κB)激活及核转移.Western Blot检测睾丸p65、IκB蛋白表达.结果显示,低、高剂量染毒组大鼠睾丸GSH/GSSG比值、GSH-Px酶活性与对照组比较降低(P,＜0.05).中、高剂量染毒组大鼠睾丸MDA含量与对照组比较升高(P,＜0.05).NAC干预组大鼠睾丸MDA含量与高ACN组比较降低(P＜0.05);NAC干预组大鼠睾丸GSH/GSSG比值与高ACN组比较升高(P＜0.05);免疫荧光结果显示,高ACN组大鼠睾丸NF-κB被激活,并转移入细胞核.NAC干预组与高ACN组比较p65蛋白表达及核转移显著减少.Western Blot结果显示,高剂量染毒组大鼠睾丸p65蛋白表达与对照组比较升高(P＜0.05),IκB蛋白表达与对照组比较降低(P＜0.05);NAC干预组大鼠睾丸p65蛋白表达与高ACN组比较降低,IκB蛋白表达与高ACN组比较升高,差异有统计学意义(P＜0.05).结果表明丙烯腈引起的氧化应激激活了大鼠睾丸生殖细胞NF-κB信号通路.

[目的]探讨丙烯腈亚慢性染毒对雄性大鼠精浆果糖和锌含量的影响以及果糖、锌含量与精液运动参数的相关关系. [方法] SPF级健康成年雄性SD大鼠40只,按体重随机分为对照组(玉米油)、低剂量组(丙烯腈12.5 mg/kg)、中剂量组(丙烯腈25 mg/kg)和高剂量组(丙烯腈50 mg/kg),每组10只.灌胃染毒,1次/d,6d/周,连续13周.于末次染毒后采用颈椎脱臼法分批处死大鼠,检测大鼠精浆中果糖、锌含量以及附睾精子密度、精子活率、精子活力.[结果]中、高剂量染毒组大鼠精囊腺和前列腺系数与对照组比较降低(P=0.045、0.011,P=0.048、0.004).低、中、高剂量染毒组大鼠精浆果糖、锌含量与对照组比较降低(P=0.002、0.000、0.000;P=0.013、0.016、0.001).低、中、高剂量染毒组大鼠精子活率与对照组比较降低(P=0.043、0.004、0.014);高剂量染毒组大鼠精子密度、精子活力与对照组比较降低(P=0.007,P=0.031).精浆果糖、锌含量与精子活率呈正相关(分别r=0.672,P=0.001;r=0.611,P=0.000).[结论]在本实验条件下,丙烯腈亚慢性染毒可以导致雄性大鼠生殖内分泌系统损害,抑制雄性大鼠精囊腺、前列腺分泌果糖和锌,影响精子密度、活率和活力,从而对精子运动及受精能力产生不良影响.