Abstract：Mammal's reproductive function is the most vulnerable to heat stress in all physiological functions. The main objectives of this research were to explore the influence of baicalin on oxidative damage of uterus tissue in mice (Mus musculus), and understand the anti-oxidation principle of baicalin. Female mice were divided into control (C) group, baicalin (Bai) group, heat stress (H) group and baicalin plus heat stress (H+Bai) group. TUNEL, spectrophotometry, Western blot and immunohistochemistry were used to detect uterine tissue structure, apoptosis and signal transduction. The results showed that, compared with the H group, the uterine tissue injury and apoptosis in mice treated with heat stress were reduced by baicalin, the content of MDA (malondialdehyde) was extremely significantly decreased (P<0.01), the activity of T-SOD (total superoxide dismutase dismutase) was extremely significantly increased (P<0.01), the activity of CAT(catalase) and GSH-Px (glutathione peroxidase) was significantly increased (P<0.05) in group H+Bai. The expression levels of Keap1 (kelch-like ECH-associated protein-1) and Nrf2 (NF-E2-related factor 2) proteins were remarkably decreased by baicalin (P<0.05), and the expressions of Bcl-2 (B-cell lymphoma-2), Bax (Bcl-2 associated X protein), Apaf-1 (apoptotic protease activating factor-1), Caspase-9 (cysteinyl aspartate specific proteinase-9) and Caspase-3 proteins in endometrial epithelial cells and adenocarcinoma epithelial cells were decreased in group H+Bai. Overall, baicalin might attenuate oxidative damage and apoptosis in endometrial epithelial cells of heat-stressed mice by activating Keap1/Nrf2 signaling pathway and then regulating the activity of antioxidant enzymes. The results of this research provide a theoretical approach to addressing animal heat stress, and provide basic information for screening anti-heat stress drugs and solving the decline of fecundity in summer dairy cattle (Bos taurus).
[1] 陈红艳, 耿淼, 胡亚卓, 等. 2011. 黄芩苷通过上调SIRT1保护SH-SY_5Y氧化应激的损伤[J]. 药学学报, 46(09): 1039-1044. (Chen H Y, Geng M, Hu Y Z, et al.2011. Effects of baicalin against oxidative stress injury of SH-SY5Y cells by up-regulating SIRT1[J]. Acta Pharmaceutica Sinica, 46(09): 1039-1044.) [2] 丛霞, 李华涛, 陈健伟, 等. 2016a. 灯盏乙素抑制热应激诱导猪肾小管上皮细胞凋亡研究[J]. 东北农业大学学报, 47(11): 59-65+84.(Cong X, Li H T, Chen J W, et al.2016. Study on scutellarin attenuates heat stress-induced apoptosis in LLC-PK1 cells[J]. Journal of Northeast Agricultural University, 47(11): 59-65+84.) [3] 丛霞, 张东君, 任婷婷. 2016b. 葛根素对热应激致牛睾丸支持细胞氧化损伤的保护作用[J]. 中国兽医杂志, 52(11): 43-46. (Cong X, Zhang D J, Ren T T.2016. Protective effect of puerarin on heat stress-induced oxidative damage in bovine sertoli cells[J]. Chinese Journal of Veterinary Medicine, 52(11): 43-46.) [4] 高琛, 隋君霞, 周颖璐, 等. 2017.黄芩苷对热应激小鼠睾丸氧化损伤的保护作用[J]. 农业生物技术学报, 25(09): 1470-1477. (Gao C, Sui J X, Zhou Y L, et al.2017. Protective effect of baicalin on oxidative damage of testes in heat stressed mice (Mus musculus)[J]. Journal of Agricultural Biotechnology, 25(09): 1470-1477.) [5] 霍爱华, 孙雪荣, 于文慧, 等. 2016. 热应激诱导猪肾小管上皮(LLC-PK1)细胞线粒体凋亡相关因子的时效表达[J]. 华北农学报, 31(06): 94-99. (Huo A H, Sun X R, Yu W H, et al.2016. Expression of factors related to mitochondrial in pig kidney proximal tubular (LLC-PK1) cells induced by heats stress[J]. Acta Agriculturae Boreali-Sinica, 31(06): 94-99.) [6] 刘琳, 钟友刚, 田金灵, 等. 2012. 热应激小鼠胚胎着床模型的建立[J]. 北京农学院学报, 27(01): 39-41. (liu L, Zhong Y G, Tian J L, et al.2012. Establishment of heat stress model about embryo implantation in mouse[J]. Journal of Beijing University of Agriculture, 27(01): 39-41.) [7] 庞纯, 蒋萍, 季莉莉. 2014. 黄芩素激活核转录因子Nrf2拮抗肝毒性的研究[J]. 中国药理学通报, 30(04): 546-549. (Pang C, Jiang P, Ji L L.2014. Baicalein induced Nrf2 activation and its protection against hepatotoxicity[J]. Chinese Pharmacological Bulletin, 30(04): 546-549.) [8] 齐晓楠, 杨文浩, 张倩, 等. 2015. 黄芩苷促进体外培养小鼠胚胎发育的研究[J]. 农业生物技术学报, 23(12): 1604-1610. (Qi X N, Yang W H, Zhang Q, et al.2015. Effects of baicalin on the development of mouse (Mus musculus) embryos cultured in vitro[J]. Journal of Agricultural Biotechnology, 23(12): 1604-1610.) [9] 任浩文, 丛霞, 李华涛, 等. 2015. 黄芩苷黄芩素小檗碱对LLC-PK1细胞炎症模型中TNF-α IL-1β及IL-6表达的影响[J]. 中国兽医杂志, 51(04): 55-58. (Ren H W, Cong X, Li H T, et al.2017. Effect of baicalin and baicalein on the expression of TNF-α, IL-1β and IL-6 in the model of LLC-PK1 cell inflammation[J]. Chinese Journal of Veterinary Medicine, 51(04): 55-58.) [10] 宋旦哥, 孟庆刚. 2009. 黄芩药理作用研究述评[J]. 中华中医药学刊, 27(08): 1619-1622. (Song D G, Meng Q G.2009. Baicalin pharmacological effects commentary[J]. Chinese Archives of Traditional Chinese Medicine, 27(08): 1619-1622.) [11] 孙春玲, 国晓瞳, 赵园, 等. 2014. 黄芩苷对热应激条件下猪近端肾小管(LLC-PK1)细胞凋亡率及B细胞淋巴瘤-2基因(Bcl-2)和Bcl-2相关X蛋白基因(Bax)表达的影响[J]. 农业生物技术学报, 22(12): 1553-1560. (Sun C L, Guo X T, Zhao Y, et al.2014. Effects of baicalin on expression of B-cellymphoma-2 (Bcl-2) and Bcl-2 assaciated X protein gene (Bax) and apoptosis rates of pig kidneyproximal tubular (LLC-PK1) cells subjected to heat stress[J]. Journal of Agricultural Biotechnology, 22(12): 1553-1560.) [12] 王雪, 姜忠玲, 王新, 等. 2017. 黄芩苷抗热应激小鼠输卵管氧化损伤的研究[J]. 华北农学报, 32(06): 147-153. (Wang X, Jiang Z L, Wang X, et al.2017. Effect of baicalin on oxidative damage of mouse oviduct induced by heat stress[J]. Acta Agriculturae Boreali-Sinica, 32(06): 147-153.) [13] 赵园, 齐晓楠, 田文儒. 2015. 热应激影响奶牛繁殖力及其应对措施[J]. 黑龙江畜牧兽医, (11): 109-112. (Zhao Y, Qi X N, Tian W R. 2015. Effect of heat stress on cow fecundity and its countermeasures[J]. Heilongjiang Animal Science and Veterinary Medicine, (11): 109-112.) [14] 周颖璐, 高琛, 姜忠玲, 等. 2018. 黄芩苷对热应激小鼠卵巢氧化损伤的保护作用[J]. 中国兽医杂志, 54(01): 21-24+66.(Zhou Y L, Gao C, Jiang Z L, et al. 2018. Protective effect of baicalin on oxidative damage of ovary in heat stressed mice[J]. Chinese Journal of Veterinary Medicine, 54(01): 21-24+66.) [15] Abed D A, Goldstein M, Albanyan H, et al.2015. Discovery of direct inhibitors of Keap1-Nrf2 protein-protein interaction as potential therapeutic and preventive agents[J]. Acta Pharmaceutica Sinica B, 5(4): 285-99. [16] Cui Y, Liu B, Xie J, et al.2014. Effect of heat stress and recovery on viability, oxidative damage, and heat shock protein expression in hepatic cells of grass carp (Ctenopharyngodon idellus)[J]. Fish Physiology and Biochemistry, 40(3): 721-729. [17] Guo X, Chi S K, Cong X, et al.2015. Baicalin protects sertoli cells from heat stress-induced apoptosis via activation of the Fas/FasL pathway and Hsp72 expression[J]. Reproductive Toxicology, 57:196-203. [18] Huang K, Gao X, Wei W.2017. The crosstalk between Sirt1 and Keap1/Nrf2/ARE anti-oxidative pathway forms a positive feedback loop to inhibit FN and TGF-beta1 expressions in rat glomerular mesangial cells[J]. Experimental Cell Research, 361(1): 63-72. [19] Sanz A B, Santamaría B, Ruiz-Ortega M, et al.2008. Mechanisms of renal apoptosis in health and disease[J]. Journal of the American Society of Nephrology, 19(9): 1634-1642. [20] Singh J, Chaudhari B P, Kakkar P.2017. Baicalin and chrysin mixture imparts cyto-protection against methylglyoxal induced cytotoxicity and diabetic tubular injury by modulating RAGE, oxidative stress and inflammation[J]. Environmental Toxicology and Pharmacology, 50: 67-75. [21] Tillerson J L, Caudle W M, Reverón M E, et al.2002. Detection of behavioral impairments correlated to neurochemical deficits in mice treated with moderate doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine[J]. Experimental Neurology, 178(1): 80-90. [22] Waisundara V Y, Hsu A, Tan B K, et al.2009. Baicalin reduces mitochondrial damage in streptozotocin-induced diabetic Wistar rats[J]. Diabetes-Metabolism Research and Reviews, 25(7): 671-677. [23] Ye L, Tao Y, Wang Y, et al.2015. The effects of baicalin on the TLR2/4 signaling pathway in the peripheral blood mononuclear cells of a lipopolysaccharide-induced rat fever model[J]. International Immunopharmacology, 25(1): 106-111.
