• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    Oxidants and Anti-Oxidants in Turbot Seminal Plasma and Their Effects on Sperm Quality

    2015-06-01 09:24:20HANMingmingDINGFuhongMENGZhenandLEIJilin
    Journal of Ocean University of China 2015年4期

    HAN Mingming, DING Fuhong, MENG Zhen, and LEI Jilin*

    1)Fisheries College,Ocean University of China,Qingdao266003,P. R. China

    2)Yellow Sea Fisheries Research Institute,Chinese Academy of Fishery Science,Qingdao266071,P. R. China

    Oxidants and Anti-Oxidants in Turbot Seminal Plasma and Their Effects on Sperm Quality

    HAN Mingming1),2), DING Fuhong2), MENG Zhen2), and LEI Jilin1),*

    1)Fisheries College,Ocean University of China,Qingdao266003,P. R. China

    2)Yellow Sea Fisheries Research Institute,Chinese Academy of Fishery Science,Qingdao266071,P. R. China

    In this research, the concentration and activity of oxidants and anti-oxidants in turbot semen, and their effects on sperm quality were studied. The results showed that superoxide dismutase (SOD), catalase, glutathione reductase (GR), uric acid, vitamin E (VE) and vitamin C (VC) were more abundant in seminal plasma than in spermatozoa. The variation for each of them was specific. In seminal plasma, the activity of SOD and GR increased from November 15, November 30 to December 15, and then decreased on December 30. The concentrations of both VCand uric acid decreased during the first 3 sampling times and increased on December 30. The oxidants in seminal plasma accumulated to the highest on December 30. Lactic acid (LA) and ATP levels decreased to the lowest on December 30. The correlation analysis showed that GR had the significant positive relevance to sperm motility and VSL/VCL, while ·OH had negative relevance to them.

    anti-oxidant; seminal plasma; sperm quality

    1 Introduction

    Increased reactive oxygen species (ROS) concentrations can impair membrane fluidity, decrease sperm motility and damage the genetic material in spermatozoa by base degradation, point mutation, DNA fragmentation and cross-linking of proteins for example, which can result in decreased semen quality and sperm motility, even the loss of their ability of fertilizing the oocytes (Agarwalet al., 2005; Bucaket al., 2010; Sharmaet al., 2004).

    The antioxidants in the seminal plasma may provide the protection to the sperm (Franzet al., 2010; Sikka, 2004). Several effective antioxidant systems in the seminal plasma, including SOD, catalase, glutathione peroxidase (GPx) and glutathione reductase (GR) have been studied thoroughly (Bucaket al., 2007). In teleost fish species, early studies have demonstrated that the seminal plasma have anti-oxidative function (Ciereszkoet al., 1999; Ciereszko and Dabrowski, 2000). In rainbow trout, SOD, ascorbic acid (VC) and uric acid have been considered as important semen antioxidants with higher concentration in seminal plasma than in blood plasma (Ciereszko and Dabrowski, 1995; Metwally and Fouad, 2009; Ciereszkoet al., 1999). In brown trout semen, Franzet al. (2010) found that uric acid and catalase showed a positive effect on sperm viability and supposed that uric acid maybe the main antioxidant since it could increase the quantity of spermatozoa with intact membranes, improve sperm motility and swimming velocity, and decrease LPO (lipid peroxidation) in sperm plasma membrane. Besides these, the glutathione and methionine antioxidant systems also exist in the seminal plasma (Franzet al., 2010). Franz and Mansour also found the superoxide dismutase and uric acid had the highest activity and concentration among the antioxidants and oxidant defensive enzymes in semen ofLota lota,Perca fluviatilis,Alburnusalburnus, andSalmo trutta. They concluded that the antioxidant systems in semen of the four species were quite uniform with only minor inter-specific differences (Franz and Mansour, 2010).

    As an important commercial fish species, turbot is drawing more and more attentions. Our previous study analyzed the turbot sperm with Computer Aided Semen Analysis (CASA) and found that the sperm quality varied during the four sampling times, Nov. 15, Nov. 30, Dec. 15 and Dec. 30, 2011 (Hanet al., 2013). In this experiment, the activities and concentrations of oxidants /antioxidants in turbot seminal plasma and their effects on sperm quality were studied. The sperm quality variation was tested according to the authors’ previous study (Hanet al., 2013). The quality parameters included semen volume, motility rate, straight line velocity (VSL), curvilinear velocity (VCL), VSL/VCL, seminal plasma protein (spp) content, sperm protein (sp) content, lactic acid (LA) and ATP levels. The anti-oxidants included SOD, catalase, uric acid, vitamin E, vitamin C, and GR. And the oxidants include H2O2, hydroxyl radicals (OH·) and the oxidizedglutathione (GSSG).

    2 Materials and Methods

    2.1 Collection of Materials

    The culture of male turbot and the semen collection followed authors’ previous study (Hanet al., 2013). The semen was collected in sterile EP tube, and stored in an ice box. Semen was centrifuged at 3000×g at 4℃ for 10 min to separate seminal fluid and spermatozoa. The supernatant of seminal fluid was collected in the sterile EP tube. The spermatozoa were homogenized in 1 mol L-1Tris-HCL, pH7.8 at a rate of 1:10 for 2-3 min. After being centrifuged at 3000×g for 10 min, the supernatant was collected into sterile EP tubes, and both the supernatant of seminal plasma and spermatozoa were separated and stored at -80℃.

    2.2 Sperm Quality Analysis

    The sperm quality was analyzed with Computer Aided Semen Analysis (CASA) and sperm concentration was calculated following our previous study (Hanet al., 2013). The concentration of seminal plasma protein and sperm protein were analyzed with the Coomassie Brilliant Blue G-250 staining kit. Bovine serum albumin was used as the standard according to the manufacturer’s instructions.

    The LA and ATP levels in the supernatant of sperm homogenate were analyzed. The LA concentration was analyzed with Vassault method (Vassault, 1983). The analysis of ATP concentration was instructed with the phosphomolybdic acid colorimetric method from the supporter. The absorbance was read with an ultravioletvisible spectrophotometer at 636 nm.

    2.3 Analysis of Antioxidants and Oxidants in Sperm and Seminal Plasma

    The supernatant of spermatozoa and seminal plasma stored at -80℃ freezer was incubated at 4℃ before analysis. All parameters were determined strictly following the instructions of the kit manufacturer (Nanjing Jiancheng Industry, China).

    According to the direction of manufacturer, in the presence of phenanthroline, both vitamin E and vitamin C can reduce Fe3+to Fe2+, and Fe2+will react with the phenanthroline to form pink compounds, after colorimetry, the content of VEand VCcan be figured up with the standard curve of formula.

    With the H+provider, NADPH, glutathione reductase can reduce oxidized glutathione (GSSG) to reduce glutathione (GSH). Through detecting the drop-out value of absorption at 340 nm of NADPH and calculating, we obtained the activity of the glutathione reductase (GR). Catalase activity was detected with a spectrophotometer (Beers and Sizer, 1952).

    Superoxide dismutase (SOD) can catalyze the superoxide anion (O2-.) into oxygen and hydrogen peroxide (H2O2). O2-.can oxidize hydroxylamine to nitrite. At the end, an amaranth reaction occurs when color agent exists. In this study, control group and experimental group were set. For the experimental group contained SOD, and less nitrite was produced. Finally, the absorbance of it was lower than the control group, and the activity of SOD was obtained at 550nmwith the formula supplied by the manufacturer.

    Hydrogen peroxide (H2O2) can react with molybdic acid and also with Fe2+to produce a kind of complex and Hydroxyl radicals (·OH), respectively, and the content of H2O2and ·OH can be determined at 405nmand 550nm.

    Through DTNB reaction, the absorbance of GSH and GSSG can be obtained at 405nm, and their concentration can be figured up according to the standard curve.

    2.4 Statistics

    Data are presented as mean ± standard deviation (n=5). Analysis of variance (ANOVA) was used to find if the concentration of antioxidants, oxidants and sperm quality changed significantly. The correlation analysis was also performed to analyze if there is a close relevance among antioxidants, oxidants and sperm quality with the ‘Analyze-Correlate-Bivariate’ function of SPSS 16.0 (P< 0.05 andR> 0.7 were considered to be significant).

    3 Results

    3.1 The Activity and Concentration of Antioxidants and Oxidants in Semen

    The activity of anti-oxidants (SOD, catalase, GR, vitamin C and uric acid) and oxidants (H2O2, ·OH and GSSG) are shown in Table 1.

    The variation for each antioxidant was specific. In seminal plasma, the activity of SOD increased significantly during the first 3 sampling times and reached the highest on Dec. 15 of 123.01 U mL-1and then decreased to 36.22 U mL-1on Dec. 30. The difference was significant during the experiment (P< 0.05). GR and vitamin C both got their highest points on Dec. 15, and then decreased to a lower point. Catalase activity varied with no significance during the experiment.

    In sperm, except for ·OH, all of the antioxidants and oxidants changed with no significance in activity or concentration during the experiment.

    3.2 Changes in Sperm Quality

    Seminal plasma protein (SPP) content, sperm protein (SP) content, lactic acid (LA) and ATP levels are shown in Table 2.

    Sperm protein concentration remained nearly constant during the four stages, while seminal plasma protein concentration (mg mL-1) varied significantly during the 4 stages and decreased from 34.56 to 13.09 (P< 0.05). LA concentration varied between 10.02 and 12.57 mmol L-1with no significant difference (P> 0.05). ATP concentration increased from 24.5 to 40.97 μmol g-1protein in the first 3 stages, and decreased to 3.21 μmol g-1protein on Dec. 30, with the significance only appearing betweenDec. 15 and Dec. 30 (P< 0.05).

    3.3 The Relevance (Rvalue) Between (Anti-)oxidants and Sperm Quality

    As shown in Table 3, among the 5 antioxidants, GR had the significant positive relevance to motility (R= 0.903,P= 0.000) and VSL/VCL (R= 0.855,P= 0.000). Both of hydroxyl radical (Rr= -0.811,P= 0.001) and hydrogen peroxide (Rp= -0.836,P= 0.001) had an negative relevance to VSL/VCL and the sperm motility rate.Notes:?These data were from author’s previous study (Hanet al., 2013). Data are mean ± standard deviation (n=5). The results marked with different letters were significantly different (P< 0.05).

    Table 1 Activity and concentration of oxidants and anti-oxidants in turbot semen at four sampling times

    Table 2 The sperm quality of turbot at four different sampling times

    Table 3 Correlations between anti-oxidants and sperm quality (n=12)

    4 Discussion

    In this experiment, we determined several kinds of anti-oxidants and oxidants in turbot semen from Nov. 15 to Dec. 30 with the intervals of two weeks. Based on the authors’ previous study and with correlation analysis, we also explored the relationship between antioxidants and sperm quality.

    Our results showed that the anti-oxidants and oxidants were more abundant in seminal plasma than in sperm, which was necessary for protecting the seminal plasma (Sikka, 2004). In seminal plasma, to anti-oxidative enzymes, SOD had the higher concentration than GR, and CAT, which was similar with the results found in brown trout (Franzet al., 2010). To the anti-oxidative metabo-lites, the concentration of vitamin C was higher than uric acid and vitamin E. Vitamin E was only found in the first two sampling times in seminal plasma, which needed more works to confirm. Though uric acid was considered the most important antioxidant in brown trout semen (Franzet al., 2010), this conclusion was inconsistent with our results. The correlation analysis showed that uric acid had no significant relevance to sperm motility, VSL/VCL, LA and ATP.

    Generally, we found that the anti-oxidants reached the lowest concentration and activity on Dec. 15, while the oxidants had the highest content on Dec. 15. The sperm quality also showed the same variation in our previous study (Hanet al., 2013). We hypothesized that during the oxidants scavenging process, though part of the oxidants were scavenged by the anti-oxidants at the beginning, as experiment proceeded, more of the oxidants were produced or accumulated because more damages were caused to anti-oxidants and this prevented the oxidantsscavenging process (Agarwalet al., 2005; Bucaket al., 2010; Sharmaet al., 2004).

    SOD and uric acid had the highest concentrations among the anti-oxidants in semen of the four species,L. lota,P. fluviatilis,A. alburnus, andS. trutta(Franz and Mansour, 2010), while through correlation analysis, we found GR had a highest positive relevance to sperm motility and VSL/VCL than others. According to glutathione peroxidase/reductase system, glutathione peroxidase (Se-GSH-Px) could act with glutathione (GSH) as the electron donor to remove reactive oxygen species (ROS) from various peroxides including H2O2, which is responsible to the lipid per-oxidation (Raghuveeret al., 2010). But with the lowest content of GR, the efficiency of it among the antioxidants need more work to find out.

    Both ·OH and H2O2had a negative relevance to sperm motility and VSL/VCL according to our correlation analysis. With the highest concentration of oxidants and lowest content of LA and ATP on Dec. 30, we inferred that as experiment proceeded, more oxidants accumulated And then this caused more damage to the intact membrane and broke up the energy production chain. Finally, the production of ATP and LD was hindered or stopped. With less energy provided, leading to the sperm had the poor motility.

    In a conclusion, the turbot seminal plasma contained more anti-oxidants and oxidants than sperm, the activity and concentration of the anti-oxidants varied as sperm quality changed. Among the several kinds of antioxidants, GR had a much higher relevance to motility and VSL/ VCL than others.

    Acknowledgements

    We thank the Tong Yong Aquaculture Industry for providing the male brood stock. We also thank those workers who collected the semen for us, and thank Dr. Guodong WANG for his support to our experiment. This study was supported by the Special Funds of Modern Agriculture Industry System Construction (CARS-50), the National Natural Science Foundation of China (3110188) and the Natural Science Foundation of Shandong Province (ZR2011CQ004).

    Agarwal, A., Gupta, S., and Sharma, R. K., 2005. Role of oxidative stress in female reproduction.Reproductive Biology and Endocrinology, 3: 1-21.

    Beers, R. F., and Sizer, I. W., 1952. A spectrophotometric method for measuring the breakdown of hydrogen peroxide by catalase.Journal of Biological Chemistry, 195 (1): 133-140.

    Bucak, M. N., Atesshin, A., Varis, O., Tekin, N., and Akcay, A., 2007. The influence of trehalose, taurine, cysteamine and hyaluronan on ram semen. Microscopic and oxidative stress parameters after freeze-thawing process.Theriogenology, 67:1060-1067.

    Bucak, M. N., Sari?zkan, S., and Tuncer, P. B., 2010. The effect of antioxidants on post-thawed Angora goat (Capra hircusancryrensis) spermparameters, lipid peroxidation and antioxidantactivities.Small Ruminant Research, 89: 24-30.

    Ciereszko, A., and Dabrowski, K., 1995. Sperm quality and ascorbic acid concentration in rainbow trout semen are affected by dietary vitamin C: An across-season study.Biology of Reproduction, 52: 982-988.

    Ciereszko, A., and Dabrowski, K., 2000. Effect of ascorbic acid supplementin vitroon rainbow trout sperm viability.Aquaculture International, 8: 1-8.

    Ciereszko, A., Dabrowski, K., Kucharczyk, D., Dobosz, S., Goryczko, K., and Glogowski, J., 1999. The presence of uric acid, an antioxidative substance, in fish seminal plasma.Fish Physiology and Biochemistry, 21: 313-315.

    Franz, L., and Mansour, N., 2010. A comparative study on antioxidant systems in semen of species of the Percidae, Salmonidae, Cyprinidae, and Lotidae for improving semen storage techniques.Aquaculture, 307: 130-140.

    Franz, L., Nabil, M., and Kristjan, P., 2010. Antioxidant systems of brown trout (Salmotrutta f. fario) semen.Animal Reproduction Science, 119: 314-321.

    Han, M. M., Ding, F. H., Meng, Z., Liu, X. F., Zhang, H. S., and Lei, J. L., 2013. The sperm quality analysis during spawning season in turbot.The Progress in Fishing Science, 34 (5): 31-35.

    Metwally, M. A. A., and Fouad, I. M., 2009. Effects of l-ascorbic acid on sperm viability in male grass carp (Ctenopharyngodonidellus).Global Veterinary, 3: 132-136.

    Raghuveer, C., Chawala, V. K., Soni, N. D., Jayant, K., and Vyas, R. K., 2010. Oxidative stress and rile of antioxidants in male infertility.Pakistan Journal of Physiology, 6 (2): 54-59.

    Rurangwa, E., Volckaert, F. A. M., and Huyskens, G., 2001. Quality control of refrigerated and cryopreserved semen using computer-assissted sperm analysis (CASA), viable staining and standardized fertilization in African catfish (Clarias gar iepinus).Theriogenology, 55: 751-769.

    Sharma, R. K., Said, T., and Agarwal, A., 2004. Sperm DNA damage and its clinical relevance in assessing reproductive outcome.Asian Journal of Andrology, 6: 139-148.

    Sikka, S. C., 2004. Role of oxidative stress and antioxidants in andrology and assisted reproductive technology.Journal of Andrology, 25: 5-18.

    Vassault, A., 1983.Methods of Enzymatic Analysis. Academic Press, New York, 118-126.

    (Edited by Qiu Yantao)

    (Received November 13, 2013; revised January 6, 2014; accepted March 31, 2015)

    ? Ocean University of China, Science Press and Spring-Verlag Berlin Heidelberg 2015

    * Corresponding author. Tel: 0086-532-85821347 E-mail: leijl35@126.com

    18+在线观看网站| 国产亚洲精品久久久久久毛片| 久久热精品热| 丰满乱子伦码专区| 熟女人妻精品中文字幕| 亚洲人成网站在线观看播放| 日本黄大片高清| 一进一出好大好爽视频| 俺也久久电影网| 精品日产1卡2卡| 在线国产一区二区在线| 婷婷精品国产亚洲av在线| 变态另类丝袜制服| 久久精品夜色国产| 18+在线观看网站| 久久热精品热| 舔av片在线| 99久国产av精品国产电影| 久久久国产成人免费| 一边摸一边抽搐一进一小说| а√天堂www在线а√下载| 欧美日韩乱码在线| 免费大片18禁| 久久人人精品亚洲av| 婷婷色综合大香蕉| 亚洲成人中文字幕在线播放| 草草在线视频免费看| 看非洲黑人一级黄片| 久久亚洲精品不卡| 日韩精品有码人妻一区| 男女下面进入的视频免费午夜| 欧美日韩精品成人综合77777| 男女视频在线观看网站免费| 亚洲人成网站在线播| 日本熟妇午夜| 草草在线视频免费看| 卡戴珊不雅视频在线播放| 久久久国产成人精品二区| 午夜免费男女啪啪视频观看 | 国产成人福利小说| 最近在线观看免费完整版| 又爽又黄a免费视频| 亚洲经典国产精华液单| 丰满的人妻完整版| 禁无遮挡网站| 可以在线观看毛片的网站| 国产午夜福利久久久久久| 99热只有精品国产| 亚洲va在线va天堂va国产| 99久久成人亚洲精品观看| 亚洲无线观看免费| 国语自产精品视频在线第100页| av卡一久久| 一级毛片电影观看 | 观看美女的网站| 99国产精品一区二区蜜桃av| 日韩成人av中文字幕在线观看 | 亚洲色图av天堂| 亚洲av五月六月丁香网| 看十八女毛片水多多多| 国内精品美女久久久久久| 一进一出抽搐gif免费好疼| 一进一出抽搐gif免费好疼| 精华霜和精华液先用哪个| 国产精品久久久久久精品电影| 日韩三级伦理在线观看| 深爱激情五月婷婷| 女人十人毛片免费观看3o分钟| 亚洲高清免费不卡视频| 插阴视频在线观看视频| 久99久视频精品免费| 在线看三级毛片| 国产大屁股一区二区在线视频| 精品不卡国产一区二区三区| 国产亚洲91精品色在线| 美女高潮的动态| 精品少妇黑人巨大在线播放 | 国产视频内射| 亚洲人成网站在线播放欧美日韩| 18+在线观看网站| 亚洲中文日韩欧美视频| 国产伦一二天堂av在线观看| 两性午夜刺激爽爽歪歪视频在线观看| 又黄又爽又免费观看的视频| 伊人久久精品亚洲午夜| 99视频精品全部免费 在线| av天堂中文字幕网| 国产精品综合久久久久久久免费| 蜜臀久久99精品久久宅男| 婷婷六月久久综合丁香| 国产亚洲91精品色在线| 亚洲aⅴ乱码一区二区在线播放| 亚洲精品456在线播放app| 少妇熟女aⅴ在线视频| 色噜噜av男人的天堂激情| 毛片一级片免费看久久久久| 国产色婷婷99| 亚洲成人精品中文字幕电影| 一边摸一边抽搐一进一小说| 麻豆一二三区av精品| 亚洲精品在线观看二区| 美女内射精品一级片tv| 成人一区二区视频在线观看| 久久国产乱子免费精品| 亚洲va在线va天堂va国产| 国内精品久久久久精免费| 在线观看av片永久免费下载| 天美传媒精品一区二区| 十八禁国产超污无遮挡网站| 在线天堂最新版资源| 久久精品久久久久久噜噜老黄 | 99riav亚洲国产免费| 国内精品宾馆在线| 免费看av在线观看网站| 成熟少妇高潮喷水视频| 亚洲精品乱码久久久v下载方式| 青春草视频在线免费观看| 在线播放无遮挡| 亚洲色图av天堂| 悠悠久久av| 欧美bdsm另类| 日韩三级伦理在线观看| 天美传媒精品一区二区| 欧美在线一区亚洲| 成人无遮挡网站| 少妇人妻精品综合一区二区 | 国产成人福利小说| 成人特级av手机在线观看| 久久久久国内视频| 99久国产av精品国产电影| 久久草成人影院| 国产单亲对白刺激| 直男gayav资源| 18+在线观看网站| h日本视频在线播放| 波多野结衣高清无吗| 亚洲精品一区av在线观看| 日本精品一区二区三区蜜桃| 欧美一区二区亚洲| 亚洲内射少妇av| 哪里可以看免费的av片| 99国产精品一区二区蜜桃av| 蜜桃亚洲精品一区二区三区| 精品不卡国产一区二区三区| 久久久精品欧美日韩精品| 如何舔出高潮| 免费在线观看影片大全网站| 久久6这里有精品| 老女人水多毛片| 亚洲成人久久性| 听说在线观看完整版免费高清| 老司机午夜福利在线观看视频| 在线观看66精品国产| 国产亚洲91精品色在线| 女的被弄到高潮叫床怎么办| 国产精品一区二区性色av| 亚洲性夜色夜夜综合| 精品日产1卡2卡| 免费观看在线日韩| 91在线精品国自产拍蜜月| 国产综合懂色| 美女大奶头视频| 最后的刺客免费高清国语| 国产精品野战在线观看| 精品人妻视频免费看| 亚洲欧美日韩卡通动漫| 日本欧美国产在线视频| 99热网站在线观看| 少妇丰满av| 亚洲av.av天堂| 亚洲内射少妇av| or卡值多少钱| 国产精品精品国产色婷婷| 嫩草影院新地址| 久久九九热精品免费| 少妇人妻精品综合一区二区 | 精品久久国产蜜桃| 18禁裸乳无遮挡免费网站照片| 欧美高清性xxxxhd video| 丝袜喷水一区| 国产精品亚洲美女久久久| 少妇熟女aⅴ在线视频| 国产三级中文精品| 日韩欧美一区二区三区在线观看| 久久久久久国产a免费观看| 国产亚洲av嫩草精品影院| 亚洲美女搞黄在线观看 | 精品午夜福利在线看| 国产精品三级大全| 美女内射精品一级片tv| 午夜精品国产一区二区电影 | 亚洲精品日韩av片在线观看| 五月玫瑰六月丁香| 国产精品精品国产色婷婷| 变态另类丝袜制服| 99在线人妻在线中文字幕| 久久韩国三级中文字幕| 国产欧美日韩一区二区精品| 国产综合懂色| 内射极品少妇av片p| 我的老师免费观看完整版| 九九久久精品国产亚洲av麻豆| 日本免费a在线| 亚洲熟妇熟女久久| av在线蜜桃| 国内少妇人妻偷人精品xxx网站| 人人妻人人澡欧美一区二区| 日日啪夜夜撸| 国产私拍福利视频在线观看| 精品免费久久久久久久清纯| 国产人妻一区二区三区在| 亚洲国产精品国产精品| 日韩,欧美,国产一区二区三区 | 97超级碰碰碰精品色视频在线观看| 国产色婷婷99| av福利片在线观看| 黄片wwwwww| 国产精品女同一区二区软件| 国产精品嫩草影院av在线观看| 亚洲三级黄色毛片| 大型黄色视频在线免费观看| 国产精华一区二区三区| 两性午夜刺激爽爽歪歪视频在线观看| 久久久久久大精品| 天堂网av新在线| 亚洲成人精品中文字幕电影| 欧美在线一区亚洲| av专区在线播放| 深夜a级毛片| 国产黄色小视频在线观看| 国产精品永久免费网站| 五月伊人婷婷丁香| 国产视频内射| 国产一级毛片七仙女欲春2| 五月玫瑰六月丁香| 最近手机中文字幕大全| 99久久成人亚洲精品观看| 日韩精品中文字幕看吧| eeuss影院久久| 搡老妇女老女人老熟妇| 国产69精品久久久久777片| 午夜视频国产福利| 亚洲成人久久性| 免费不卡的大黄色大毛片视频在线观看 | 国产一区二区在线观看日韩| 免费大片18禁| 夜夜夜夜夜久久久久| 久久亚洲国产成人精品v| 免费av不卡在线播放| 国产高清激情床上av| 午夜亚洲福利在线播放| aaaaa片日本免费| 亚洲欧美日韩东京热| 国产精品免费一区二区三区在线| 国产精品久久久久久久久免| 2021天堂中文幕一二区在线观| 男人和女人高潮做爰伦理| 欧美最新免费一区二区三区| 淫秽高清视频在线观看| 精品日产1卡2卡| av在线亚洲专区| 男人和女人高潮做爰伦理| 人人妻人人看人人澡| 99国产极品粉嫩在线观看| 国模一区二区三区四区视频| 大又大粗又爽又黄少妇毛片口| 久久精品人妻少妇| 天美传媒精品一区二区| 国产 一区 欧美 日韩| 精品一区二区三区人妻视频| 少妇裸体淫交视频免费看高清| 亚洲欧美中文字幕日韩二区| 国内精品一区二区在线观看| 色哟哟·www| 国产91av在线免费观看| 在线观看av片永久免费下载| 夜夜爽天天搞| 国产色婷婷99| eeuss影院久久| 国产一区二区亚洲精品在线观看| 如何舔出高潮| 精品一区二区三区人妻视频| 久久6这里有精品| 免费人成在线观看视频色| 国内揄拍国产精品人妻在线| 国产麻豆成人av免费视频| 大香蕉久久网| 亚洲精品粉嫩美女一区| 中文字幕免费在线视频6| 国产精品一区二区三区四区免费观看 | 国产一区二区激情短视频| 一卡2卡三卡四卡精品乱码亚洲| 悠悠久久av| 久久久精品94久久精品| 亚洲精品乱码久久久v下载方式| 国产精品久久久久久亚洲av鲁大| 99国产精品一区二区蜜桃av| 国产精品一区二区免费欧美| 久久热精品热| 精品久久久久久久末码| 亚洲精华国产精华液的使用体验 | 黑人高潮一二区| 51国产日韩欧美| 又黄又爽又免费观看的视频| 欧美精品国产亚洲| 少妇熟女欧美另类| 97超碰精品成人国产| www日本黄色视频网| 国产精品久久视频播放| 国产色婷婷99| av天堂在线播放| 一个人免费在线观看电影| 国产乱人偷精品视频| 日韩av不卡免费在线播放| 性色avwww在线观看| 欧美人与善性xxx| 久久精品国产清高在天天线| 午夜激情福利司机影院| 久久久久国产网址| 波多野结衣高清作品| 极品教师在线视频| 久久精品人妻少妇| 国产精品久久久久久av不卡| 久久久欧美国产精品| 国产精品免费一区二区三区在线| 日本黄色片子视频| 日本黄色视频三级网站网址| 欧美一区二区亚洲| 日本一本二区三区精品| 97人妻精品一区二区三区麻豆| 亚洲精品国产av成人精品 | a级毛片免费高清观看在线播放| 99久久成人亚洲精品观看| 日韩欧美精品v在线| 给我免费播放毛片高清在线观看| 日韩国内少妇激情av| 国产高清视频在线观看网站| 午夜激情欧美在线| 免费无遮挡裸体视频| 国产精品日韩av在线免费观看| 直男gayav资源| 国产av在哪里看| 欧美xxxx黑人xx丫x性爽| 蜜桃亚洲精品一区二区三区| 天天躁夜夜躁狠狠久久av| 六月丁香七月| 在线播放国产精品三级| 亚洲欧美精品自产自拍| 国产精品国产三级国产av玫瑰| 99热这里只有是精品在线观看| 永久网站在线| 亚洲欧美日韩卡通动漫| 可以在线观看毛片的网站| 成人国产麻豆网| aaaaa片日本免费| 在线观看免费视频日本深夜| av免费在线看不卡| 一本久久中文字幕| 大香蕉久久网| or卡值多少钱| 黄色欧美视频在线观看| 村上凉子中文字幕在线| 久99久视频精品免费| 亚洲电影在线观看av| 午夜亚洲福利在线播放| a级一级毛片免费在线观看| 日日撸夜夜添| 秋霞在线观看毛片| 欧美区成人在线视频| 免费高清视频大片| 在线看三级毛片| 日韩欧美 国产精品| 嫩草影院入口| 国产精品乱码一区二三区的特点| 97超视频在线观看视频| 国产视频内射| 国产午夜福利久久久久久| av卡一久久| 午夜日韩欧美国产| 国产欧美日韩精品亚洲av| 欧美高清性xxxxhd video| 亚洲激情五月婷婷啪啪| 性色avwww在线观看| 伊人久久精品亚洲午夜| 我要看日韩黄色一级片| 天堂网av新在线| 3wmmmm亚洲av在线观看| 国产片特级美女逼逼视频| 欧美绝顶高潮抽搐喷水| 亚洲18禁久久av| 又爽又黄无遮挡网站| 精品一区二区三区视频在线观看免费| 免费观看人在逋| 国产 一区 欧美 日韩| 欧美日韩在线观看h| 一本一本综合久久| 国产视频一区二区在线看| 亚洲av第一区精品v没综合| 国产激情偷乱视频一区二区| 久久中文看片网| 久久精品国产亚洲av天美| 亚洲欧美日韩无卡精品| 最近2019中文字幕mv第一页| 我的老师免费观看完整版| 日韩欧美精品免费久久| 成人高潮视频无遮挡免费网站| 我要看日韩黄色一级片| 国产av麻豆久久久久久久| www.色视频.com| 成人二区视频| 久久欧美精品欧美久久欧美| 麻豆成人午夜福利视频| 高清毛片免费观看视频网站| av在线老鸭窝| 美女大奶头视频| 给我免费播放毛片高清在线观看| 一级毛片aaaaaa免费看小| 亚洲欧美日韩无卡精品| 亚洲欧美日韩卡通动漫| 亚洲国产日韩欧美精品在线观看| 99在线人妻在线中文字幕| 亚洲av成人精品一区久久| 国产成人91sexporn| 中文字幕免费在线视频6| 日韩欧美精品v在线| a级毛色黄片| 麻豆久久精品国产亚洲av| 春色校园在线视频观看| 两性午夜刺激爽爽歪歪视频在线观看| 亚洲自偷自拍三级| 在线播放国产精品三级| 12—13女人毛片做爰片一| 岛国在线免费视频观看| 日韩欧美在线乱码| 18禁黄网站禁片免费观看直播| 久久久色成人| 国产伦精品一区二区三区四那| 热99在线观看视频| 国产美女午夜福利| av天堂中文字幕网| 中文字幕熟女人妻在线| 国产中年淑女户外野战色| 在线a可以看的网站| 91在线精品国自产拍蜜月| 国产成人a区在线观看| 18禁黄网站禁片免费观看直播| 麻豆精品久久久久久蜜桃| 国产视频一区二区在线看| 日本爱情动作片www.在线观看 | 国产精品亚洲一级av第二区| 在线免费观看的www视频| 男人和女人高潮做爰伦理| 亚洲欧美成人精品一区二区| 国内揄拍国产精品人妻在线| 给我免费播放毛片高清在线观看| 色综合色国产| a级毛片免费高清观看在线播放| 十八禁国产超污无遮挡网站| 男人舔女人下体高潮全视频| 亚洲精品色激情综合| 国产女主播在线喷水免费视频网站 | 成人特级黄色片久久久久久久| 亚洲av熟女| 精品少妇黑人巨大在线播放 | 伊人久久精品亚洲午夜| 久久精品影院6| 淫妇啪啪啪对白视频| 深夜a级毛片| 亚洲人与动物交配视频| 身体一侧抽搐| 亚洲高清免费不卡视频| 不卡视频在线观看欧美| a级毛片免费高清观看在线播放| 久久久久精品国产欧美久久久| 国产不卡一卡二| 蜜桃亚洲精品一区二区三区| 自拍偷自拍亚洲精品老妇| 可以在线观看的亚洲视频| 身体一侧抽搐| 精品欧美国产一区二区三| 久久精品91蜜桃| 99久久精品国产国产毛片| 亚洲人成网站在线播放欧美日韩| 国产精品久久视频播放| 看十八女毛片水多多多| 91久久精品国产一区二区成人| 国产精品国产高清国产av| 国产高清有码在线观看视频| 国产免费男女视频| 免费看美女性在线毛片视频| 国产精品不卡视频一区二区| 日韩强制内射视频| 亚洲,欧美,日韩| 在线观看午夜福利视频| 成人毛片a级毛片在线播放| 久99久视频精品免费| 大型黄色视频在线免费观看| 成人性生交大片免费视频hd| 国产免费一级a男人的天堂| 男插女下体视频免费在线播放| 女同久久另类99精品国产91| 精品久久久久久久末码| 国产精品1区2区在线观看.| 久久久久九九精品影院| 亚洲精品在线观看二区| 尤物成人国产欧美一区二区三区| 欧美性猛交黑人性爽| 色综合色国产| 久99久视频精品免费| 婷婷色综合大香蕉| 精品国内亚洲2022精品成人| av视频在线观看入口| 亚洲一区二区三区色噜噜| 女人被狂操c到高潮| 丰满人妻一区二区三区视频av| 免费av观看视频| 男女视频在线观看网站免费| 大型黄色视频在线免费观看| 亚洲精品乱码久久久v下载方式| 有码 亚洲区| 少妇熟女aⅴ在线视频| 精品欧美国产一区二区三| 亚洲国产精品sss在线观看| 国产精品一区二区免费欧美| 午夜亚洲福利在线播放| 国产一级毛片七仙女欲春2| 一级av片app| 黑人高潮一二区| 欧美激情国产日韩精品一区| 午夜精品在线福利| av国产免费在线观看| 中文字幕久久专区| 女人十人毛片免费观看3o分钟| 两个人的视频大全免费| 欧美另类亚洲清纯唯美| 久久精品综合一区二区三区| 婷婷精品国产亚洲av| 少妇人妻精品综合一区二区 | 色吧在线观看| 亚洲,欧美,日韩| 毛片女人毛片| 五月伊人婷婷丁香| 一级毛片aaaaaa免费看小| 91久久精品国产一区二区成人| 成人毛片a级毛片在线播放| 精品99又大又爽又粗少妇毛片| 国产精品三级大全| 免费av不卡在线播放| 韩国av在线不卡| 色吧在线观看| 久久精品国产亚洲av涩爱 | 亚洲在线自拍视频| 最近中文字幕高清免费大全6| 两个人的视频大全免费| 九九爱精品视频在线观看| 久久久精品94久久精品| 精品不卡国产一区二区三区| 日本黄色片子视频| 十八禁网站免费在线| 免费看光身美女| 简卡轻食公司| 菩萨蛮人人尽说江南好唐韦庄 | 一级av片app| 99在线人妻在线中文字幕| 成年版毛片免费区| 一级黄片播放器| 精品乱码久久久久久99久播| 免费看光身美女| 国产精品一区www在线观看| 久久精品国产亚洲av香蕉五月| 天堂av国产一区二区熟女人妻| videossex国产| 国产精品福利在线免费观看| 精品久久久久久久久久免费视频| 欧美激情在线99| 日韩精品青青久久久久久| 午夜久久久久精精品| 一个人免费在线观看电影| 国产高潮美女av| 久久久久久久久久久丰满| 乱人视频在线观看| 不卡一级毛片| 蜜桃久久精品国产亚洲av| 嫩草影院精品99| 精品熟女少妇av免费看| 精品日产1卡2卡| 91久久精品国产一区二区三区| 在线天堂最新版资源| 中文字幕人妻熟人妻熟丝袜美| 亚洲av一区综合| 欧美一区二区精品小视频在线| 九九爱精品视频在线观看| 中国国产av一级| 在线天堂最新版资源| 欧美成人免费av一区二区三区| 色综合站精品国产| 欧美日韩一区二区视频在线观看视频在线 | 最近在线观看免费完整版| 亚洲美女视频黄频| 国产成人一区二区在线| av女优亚洲男人天堂| www.色视频.com| 国产探花极品一区二区| 欧美xxxx性猛交bbbb| 久久久久久久久久黄片| 亚洲国产精品合色在线| 99热6这里只有精品| 亚洲一级一片aⅴ在线观看| 日韩精品中文字幕看吧| 在线看三级毛片| 久久精品影院6| 在线观看免费视频日本深夜| 亚洲欧美精品综合久久99| 狂野欧美激情性xxxx在线观看| 国产成人精品久久久久久|