• <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

    国产伦理片在线播放av一区| 国产男人的电影天堂91| 女人十人毛片免费观看3o分钟| 18禁在线无遮挡免费观看视频| 欧美xxⅹ黑人| 人妻 亚洲 视频| 男女那种视频在线观看| 高清在线视频一区二区三区| 六月丁香七月| 欧美精品国产亚洲| av免费观看日本| 国产一区二区三区av在线| 男人舔奶头视频| 欧美精品一区二区大全| 纵有疾风起免费观看全集完整版| av.在线天堂| 我的老师免费观看完整版| h日本视频在线播放| 亚洲经典国产精华液单| 熟女电影av网| 欧美精品一区二区大全| 日韩精品有码人妻一区| 色吧在线观看| 一级片'在线观看视频| 免费看a级黄色片| 亚洲av日韩在线播放| 白带黄色成豆腐渣| 大香蕉久久网| 国产老妇女一区| av福利片在线观看| 99视频精品全部免费 在线| 亚洲国产高清在线一区二区三| 国产老妇女一区| 欧美日韩一区二区视频在线观看视频在线 | 精品久久久久久久末码| 国产淫片久久久久久久久| 日日啪夜夜爽| 熟女电影av网| 大码成人一级视频| 国产精品熟女久久久久浪| 极品少妇高潮喷水抽搐| 欧美最新免费一区二区三区| 日韩制服骚丝袜av| 亚洲国产最新在线播放| 亚洲av成人精品一区久久| 最近中文字幕2019免费版| 视频区图区小说| 最近中文字幕高清免费大全6| 欧美丝袜亚洲另类| 欧美日本视频| 亚洲熟女精品中文字幕| 嫩草影院新地址| 国产精品伦人一区二区| 高清视频免费观看一区二区| 日本色播在线视频| 在线观看美女被高潮喷水网站| 久久99热6这里只有精品| 欧美老熟妇乱子伦牲交| 欧美亚洲 丝袜 人妻 在线| 一级毛片电影观看| 韩国高清视频一区二区三区| 日韩国内少妇激情av| 街头女战士在线观看网站| 99九九线精品视频在线观看视频| 超碰97精品在线观看| 亚洲在久久综合| 97人妻精品一区二区三区麻豆| 色视频在线一区二区三区| 日本黄色片子视频| 中文资源天堂在线| 日韩中字成人| 视频中文字幕在线观看| 免费黄色在线免费观看| 国产伦精品一区二区三区四那| 三级国产精品欧美在线观看| 国产黄a三级三级三级人| 一本一本综合久久| 九九在线视频观看精品| 在线观看一区二区三区| 国产精品久久久久久av不卡| tube8黄色片| 免费观看在线日韩| 国产一区二区亚洲精品在线观看| 在线免费观看不下载黄p国产| 国产成人午夜福利电影在线观看| 国产精品无大码| 综合色丁香网| 欧美成人精品欧美一级黄| 日本熟妇午夜| 91aial.com中文字幕在线观看| 日韩三级伦理在线观看| 青青草视频在线视频观看| 少妇裸体淫交视频免费看高清| 欧美日韩国产mv在线观看视频 | 中文乱码字字幕精品一区二区三区| 国产中年淑女户外野战色| 国产成人a∨麻豆精品| 国产片特级美女逼逼视频| 国产一级毛片在线| 免费少妇av软件| 九草在线视频观看| 天堂中文最新版在线下载 | 国产av国产精品国产| 亚洲精品成人av观看孕妇| 欧美老熟妇乱子伦牲交| 日韩精品有码人妻一区| 男人和女人高潮做爰伦理| 联通29元200g的流量卡| 欧美亚洲 丝袜 人妻 在线| 一级二级三级毛片免费看| 青春草国产在线视频| 不卡视频在线观看欧美| www.色视频.com| 日本一二三区视频观看| 秋霞伦理黄片| 久久精品夜色国产| 高清在线视频一区二区三区| 亚洲精品一二三| 国产免费一级a男人的天堂| 自拍偷自拍亚洲精品老妇| 免费av毛片视频| 国产高清国产精品国产三级 | 免费观看的影片在线观看| 黄色视频在线播放观看不卡| 99热这里只有精品一区| 国产午夜精品一二区理论片| 波野结衣二区三区在线| 神马国产精品三级电影在线观看| 中国三级夫妇交换| 久久久久久久精品精品| 国产精品一区www在线观看| 中文字幕人妻熟人妻熟丝袜美| 你懂的网址亚洲精品在线观看| 免费不卡的大黄色大毛片视频在线观看| 亚洲最大成人手机在线| 97超碰精品成人国产| 亚洲一区二区三区欧美精品 | 国产免费又黄又爽又色| av在线观看视频网站免费| 天美传媒精品一区二区| 别揉我奶头 嗯啊视频| 一级毛片黄色毛片免费观看视频| 在线观看国产h片| 亚洲精品456在线播放app| 亚洲色图av天堂| 丰满人妻一区二区三区视频av| 熟女人妻精品中文字幕| 亚洲最大成人中文| 自拍欧美九色日韩亚洲蝌蚪91 | 大香蕉97超碰在线| 国产欧美日韩一区二区三区在线 | av在线app专区| 大又大粗又爽又黄少妇毛片口| 99re6热这里在线精品视频| 午夜福利网站1000一区二区三区| 精品国产三级普通话版| 欧美国产精品一级二级三级 | 亚洲欧美日韩无卡精品| 国产黄a三级三级三级人| 欧美日韩国产mv在线观看视频 | 新久久久久国产一级毛片| 精品少妇黑人巨大在线播放| 日韩av在线免费看完整版不卡| 国产成年人精品一区二区| 国精品久久久久久国模美| 国产黄色视频一区二区在线观看| 中文字幕亚洲精品专区| 国产 一区 欧美 日韩| 18+在线观看网站| 麻豆久久精品国产亚洲av| 五月伊人婷婷丁香| 色哟哟·www| 禁无遮挡网站| 直男gayav资源| 一个人看视频在线观看www免费| 蜜臀久久99精品久久宅男| 777米奇影视久久| 久久午夜福利片| 国产成人freesex在线| 九九在线视频观看精品| 欧美日韩精品成人综合77777| 亚洲精品国产成人久久av| 国产精品久久久久久精品电影小说 | 新久久久久国产一级毛片| 国产成人精品福利久久| 久久久成人免费电影| 最近2019中文字幕mv第一页| 国产毛片a区久久久久| 777米奇影视久久| 婷婷色av中文字幕| 国产女主播在线喷水免费视频网站| 嫩草影院精品99| 九九爱精品视频在线观看| 亚洲精品aⅴ在线观看| 超碰av人人做人人爽久久| 99久久人妻综合| 日韩av在线免费看完整版不卡| 丝袜美腿在线中文| 久热这里只有精品99| 亚洲天堂av无毛| 国产亚洲精品久久久com| 国产伦在线观看视频一区| 免费av毛片视频| 久久精品国产亚洲网站| 制服丝袜香蕉在线| 卡戴珊不雅视频在线播放| 精品久久久噜噜| 亚洲欧美精品专区久久| 国产精品嫩草影院av在线观看| 91狼人影院| 国产精品偷伦视频观看了| 久久影院123| 麻豆乱淫一区二区| a级一级毛片免费在线观看| 寂寞人妻少妇视频99o| 免费播放大片免费观看视频在线观看| 深爱激情五月婷婷| 国产成人aa在线观看| 国产综合懂色| www.av在线官网国产| 97人妻精品一区二区三区麻豆| 视频中文字幕在线观看| 欧美3d第一页| 日日摸夜夜添夜夜添av毛片| 成人毛片a级毛片在线播放| 丰满人妻一区二区三区视频av| 卡戴珊不雅视频在线播放| 又爽又黄无遮挡网站| 欧美日本视频| 亚洲一区二区三区欧美精品 | 亚洲丝袜综合中文字幕| 国内精品美女久久久久久| 各种免费的搞黄视频| 丰满少妇做爰视频| 大陆偷拍与自拍| 国产伦精品一区二区三区视频9| 一区二区三区免费毛片| 久久久久久久久久久丰满| 网址你懂的国产日韩在线| 麻豆久久精品国产亚洲av| 不卡视频在线观看欧美| 精品国产乱码久久久久久小说| 欧美日韩国产mv在线观看视频 | 香蕉精品网在线| 国产一区二区三区综合在线观看 | 成人毛片a级毛片在线播放| 免费大片18禁| 欧美成人精品欧美一级黄| 在线a可以看的网站| 一本色道久久久久久精品综合| 日本欧美国产在线视频| 久热这里只有精品99| 亚洲欧洲国产日韩| 热re99久久精品国产66热6| 亚洲av日韩在线播放| 亚洲国产精品成人综合色| 18+在线观看网站| 18禁裸乳无遮挡动漫免费视频 | 最近最新中文字幕免费大全7| 亚洲精品456在线播放app| av网站免费在线观看视频| 大片免费播放器 马上看| 欧美日本视频| 又粗又硬又长又爽又黄的视频| 国产久久久一区二区三区| 2021天堂中文幕一二区在线观| 大香蕉97超碰在线| 欧美区成人在线视频| 亚洲精品久久午夜乱码| 91精品一卡2卡3卡4卡| 大码成人一级视频| 真实男女啪啪啪动态图| 最新中文字幕久久久久| 成人二区视频| 免费看a级黄色片| 亚洲欧美中文字幕日韩二区| 国产精品一区二区性色av| 久久午夜福利片| 十八禁网站网址无遮挡 | 大码成人一级视频| 国产 一区 欧美 日韩| 久久精品国产自在天天线| 免费在线观看成人毛片| 亚洲精品亚洲一区二区| 久久久久网色| av在线蜜桃| 一级毛片我不卡| 人妻制服诱惑在线中文字幕| 亚洲av一区综合| 成年女人在线观看亚洲视频 | 欧美变态另类bdsm刘玥| 男女边吃奶边做爰视频| 大又大粗又爽又黄少妇毛片口| 草草在线视频免费看| 又爽又黄无遮挡网站| 日韩av不卡免费在线播放| 国产精品熟女久久久久浪| 国产高清不卡午夜福利| 男男h啪啪无遮挡| 国产探花极品一区二区| 偷拍熟女少妇极品色| 秋霞伦理黄片| 男女边吃奶边做爰视频| 国产久久久一区二区三区| 两个人的视频大全免费| 国产亚洲av嫩草精品影院| 伦理电影大哥的女人| 青青草视频在线视频观看| 国产午夜精品一二区理论片| 成人特级av手机在线观看| 国产成人精品一,二区| 亚洲综合色惰| 国产综合懂色| 亚洲精品乱久久久久久| 久久久a久久爽久久v久久| 国产伦精品一区二区三区视频9| 香蕉精品网在线| av播播在线观看一区| 亚洲欧美日韩另类电影网站 | 亚洲自拍偷在线| 亚洲欧美日韩另类电影网站 | av国产免费在线观看| 久久人人爽人人片av| av.在线天堂| 日韩欧美精品免费久久| 99视频精品全部免费 在线| 久久久精品94久久精品| 特大巨黑吊av在线直播| 成人黄色视频免费在线看| 日韩亚洲欧美综合| 久久鲁丝午夜福利片| 丰满乱子伦码专区| 亚洲精品一二三| 成人特级av手机在线观看| 大又大粗又爽又黄少妇毛片口| 爱豆传媒免费全集在线观看| 真实男女啪啪啪动态图| 亚洲国产欧美在线一区| 久久久久久久亚洲中文字幕| 亚洲精品色激情综合| 免费黄频网站在线观看国产| 日本wwww免费看| 中文字幕亚洲精品专区| 少妇人妻 视频| 欧美 日韩 精品 国产| 国产精品无大码| 性色av一级| av在线观看视频网站免费| 韩国av在线不卡| 亚洲精品日韩在线中文字幕| 建设人人有责人人尽责人人享有的 | 久久久久久久久久久免费av| 亚洲高清免费不卡视频| 精品国产露脸久久av麻豆| 亚洲国产最新在线播放| 肉色欧美久久久久久久蜜桃 | 国产精品国产三级专区第一集| 精品人妻熟女av久视频| 日韩av在线免费看完整版不卡| 国产成人aa在线观看| 久久热精品热| 99热6这里只有精品| 在线观看av片永久免费下载| 久久久久国产精品人妻一区二区| 男的添女的下面高潮视频| 国产淫片久久久久久久久| 国产免费一级a男人的天堂| 久久久色成人| av网站免费在线观看视频| 人妻少妇偷人精品九色| 亚洲精品日韩在线中文字幕| 成人鲁丝片一二三区免费| 亚洲欧美日韩无卡精品| 国产91av在线免费观看| 国内揄拍国产精品人妻在线| 久久久久久久久久久丰满| 国产精品久久久久久精品电影小说 | 国产永久视频网站| 久久久久网色| 亚洲精品日韩在线中文字幕| 欧美3d第一页| 免费播放大片免费观看视频在线观看| av在线app专区| 一级毛片 在线播放| 真实男女啪啪啪动态图| 亚洲国产欧美人成| 成人午夜精彩视频在线观看| 青春草亚洲视频在线观看| 人人妻人人爽人人添夜夜欢视频 | 免费观看a级毛片全部| 国产精品久久久久久久久免| 久久久久精品久久久久真实原创| 国产日韩欧美亚洲二区| 大码成人一级视频| 少妇的逼水好多| 亚洲av电影在线观看一区二区三区 | 亚洲精品色激情综合| 国产免费又黄又爽又色| 亚洲精品国产成人久久av| 亚洲精品一二三| 国产综合精华液| 一个人看视频在线观看www免费| 精品一区在线观看国产| 欧美高清性xxxxhd video| 免费看a级黄色片| 亚洲精品国产av成人精品| 在线播放无遮挡| 一本—道久久a久久精品蜜桃钙片 精品乱码久久久久久99久播 | 国产日韩欧美亚洲二区| 两个人的视频大全免费| 久久6这里有精品| 国产淫语在线视频| 精品久久久久久久久亚洲| 一本一本综合久久| 九草在线视频观看| a级毛片免费高清观看在线播放| 伊人久久国产一区二区| 久久精品人妻少妇| 毛片一级片免费看久久久久| 欧美老熟妇乱子伦牲交| 亚洲精品色激情综合| 亚洲成人一二三区av| 在线看a的网站| 精品少妇久久久久久888优播| 日本一本二区三区精品| 深夜a级毛片| 老司机影院成人| 看十八女毛片水多多多| 亚洲精品国产色婷婷电影| av在线老鸭窝| 一级毛片电影观看| 天天一区二区日本电影三级| 最后的刺客免费高清国语| 亚洲欧美一区二区三区黑人 | 日本一二三区视频观看| 日韩人妻高清精品专区| 国产一级毛片在线| 最近最新中文字幕免费大全7| 国产一区有黄有色的免费视频| 亚洲国产av新网站| 国产一级毛片在线| 汤姆久久久久久久影院中文字幕| 亚洲av免费高清在线观看| 国产男女超爽视频在线观看| 一级毛片久久久久久久久女| 看黄色毛片网站| 亚洲av男天堂| 亚洲美女搞黄在线观看| 亚洲欧美精品专区久久| 乱系列少妇在线播放| 国产有黄有色有爽视频| 亚洲欧美日韩卡通动漫| 亚洲色图av天堂| 午夜福利视频1000在线观看| 22中文网久久字幕| 晚上一个人看的免费电影| 一区二区av电影网| 国产免费又黄又爽又色| 欧美一区二区亚洲| 在线a可以看的网站| 久久久久网色| 国产一区二区三区av在线| 99久久人妻综合| 久久人人爽人人爽人人片va| 日韩成人伦理影院| 精品久久久久久久末码| 国内少妇人妻偷人精品xxx网站| 国产亚洲一区二区精品| 精品一区二区免费观看| 久热这里只有精品99| 日韩成人av中文字幕在线观看| 亚洲国产日韩一区二区| 深爱激情五月婷婷| 特级一级黄色大片| 黄色怎么调成土黄色| 岛国毛片在线播放| 久久6这里有精品| 白带黄色成豆腐渣| 卡戴珊不雅视频在线播放| 女人久久www免费人成看片| 国产成人a∨麻豆精品| 亚洲成人av在线免费| 最近手机中文字幕大全| 欧美三级亚洲精品| 中文乱码字字幕精品一区二区三区| 亚洲第一区二区三区不卡| 色婷婷久久久亚洲欧美| 纵有疾风起免费观看全集完整版| 在线免费十八禁| 亚洲av中文av极速乱| 日韩 亚洲 欧美在线| 国产永久视频网站| 少妇人妻精品综合一区二区| 91久久精品电影网| 在现免费观看毛片| 久久久久久九九精品二区国产| 色婷婷久久久亚洲欧美| 国产高潮美女av| 久久久久精品性色| 日韩av不卡免费在线播放| 国产中年淑女户外野战色| 神马国产精品三级电影在线观看| 韩国高清视频一区二区三区| 日韩中字成人| av黄色大香蕉| 在线观看三级黄色| 成人综合一区亚洲| 麻豆国产97在线/欧美| 人妻 亚洲 视频| 一边亲一边摸免费视频| 夜夜爽夜夜爽视频| xxx大片免费视频| 日韩电影二区| 亚洲内射少妇av| 久久这里有精品视频免费| 爱豆传媒免费全集在线观看| 成人综合一区亚洲| 国产成人福利小说| 国产伦精品一区二区三区四那| 久久精品综合一区二区三区| 亚洲人成网站在线观看播放| 嫩草影院精品99| 欧美+日韩+精品| 午夜免费鲁丝| 看十八女毛片水多多多| 丰满少妇做爰视频| 精品熟女少妇av免费看| 久久久久网色| 亚洲av中文av极速乱| 久久99热6这里只有精品| 久久国产乱子免费精品| a级毛色黄片| 亚洲自拍偷在线| 久久久久久久大尺度免费视频| 国内揄拍国产精品人妻在线| 成年女人在线观看亚洲视频 | 欧美激情久久久久久爽电影| 国产成人免费无遮挡视频| av网站免费在线观看视频| 午夜精品国产一区二区电影 | 国产综合懂色| 偷拍熟女少妇极品色| 欧美三级亚洲精品| 久热久热在线精品观看| 少妇的逼好多水| 亚洲色图av天堂| 免费黄色在线免费观看| 国产伦精品一区二区三区视频9| 看黄色毛片网站| 欧美日韩国产mv在线观看视频 | 一级毛片久久久久久久久女| 精品熟女少妇av免费看| 国产精品蜜桃在线观看| 一级片'在线观看视频| 亚洲欧美日韩东京热| 麻豆成人午夜福利视频| 日韩不卡一区二区三区视频在线| 国产精品国产av在线观看| 亚洲婷婷狠狠爱综合网| 只有这里有精品99| 一级爰片在线观看| 日日摸夜夜添夜夜爱| 成人毛片a级毛片在线播放| 免费黄网站久久成人精品| 亚洲精品国产色婷婷电影| 精品国产露脸久久av麻豆| 又爽又黄无遮挡网站| 国产亚洲91精品色在线| 五月开心婷婷网| 97精品久久久久久久久久精品| 亚洲av男天堂| 人人妻人人爽人人添夜夜欢视频 | 国产av不卡久久| 三级经典国产精品| 麻豆精品久久久久久蜜桃| 国产欧美另类精品又又久久亚洲欧美| 人妻制服诱惑在线中文字幕| 亚洲欧美一区二区三区国产| 精品久久久久久电影网| 欧美日本视频| 五月天丁香电影| 亚洲美女视频黄频| 国产毛片在线视频| 国产淫片久久久久久久久| 成人国产麻豆网| 在线播放无遮挡| 久久久色成人| 亚洲美女视频黄频| 色5月婷婷丁香| 久久久久网色| 日韩制服骚丝袜av| 高清视频免费观看一区二区| av女优亚洲男人天堂| 日本wwww免费看| 亚洲性久久影院| 插阴视频在线观看视频| 美女主播在线视频| 久久久欧美国产精品| 亚洲最大成人手机在线| 精品国产三级普通话版| 色5月婷婷丁香| 亚洲欧美中文字幕日韩二区| 久久久久久久久大av| 国产探花极品一区二区| 最近的中文字幕免费完整| 97超视频在线观看视频| 精品酒店卫生间| 国产精品一二三区在线看| 又粗又硬又长又爽又黄的视频| 波野结衣二区三区在线| 成人二区视频| 男女国产视频网站| 日本-黄色视频高清免费观看| 99热这里只有精品一区| 久久综合国产亚洲精品|