目的:探究稀土元素钇暴露是否通过诱发睾丸氧化应激而损伤精子质量。方法:使用4周龄清洁级BALB/C雄性小鼠80只,染毒实验40只,分为对照组(NC)、4、20和100 mg/kg硝酸钇组;氧化应激抑制实验40只,分为NC、100 mg/kg N-乙酰半胱氨酸(NAC)组、100 mg/kg硝酸钇组、100 mg/kg硝酸钇组+100 mg/kg NAC组。血细胞计数法计算精子数量,伊红-苯胺黑法检测精子畸形率、流式细胞术检测精子凋亡率、HE法检测小鼠睾丸组织结构、ELISA检测睾丸组织白细胞介素1β(IL-1β)和肿瘤坏死因子α(TNF-α)表达量、试剂盒检测睾丸组织活性氧(ROS)和丙二醛(MDA)含量。结果:(1)与NC组相比,100 mg/kg硝酸钇组的精子数量明显下降(P＜0.01),而畸形率升高(P＜0.001),精子凋亡率增加(P＜0.01);(2)与NC组相比,100 mg/kg硝酸钇组小鼠睾丸生精小管上皮厚度变薄,间质水肿和血管扩张,生精细胞排列松散无序,生精细胞数量减少;(3)100 mg/kg硝酸钇组睾丸IL-1β和TNF-α表达量高于NC组(P＜0.05);(4)与NC组相比,100 mg/kg硝酸钇组小鼠睾丸ROS明显升高(P＜0.01)、MDA水平升高(P＜0.05);(5)与100 mg/kg硝酸钇组相比,100 mg/kg硝酸钇+100 mg/kg NAC组ROS和MDA含量降低(P＜0.05),IL-1β和TNF-α表达量降低(P＜0.05),精子数量明显升高(P＜0.01),而畸形率下降(P＜0.01)。结论:长期暴露于高剂量钇可能诱发睾丸氧化应激,引起睾丸炎症,损伤睾丸组织结构,进而导致精子质量下降。
Objective: To investigate whether exposure to rare earth element yttrium damaging sperm quality by inducing testicular oxidative stress.Methods: A total of 80 BALB/C male mice aged 4 weeks were used, 40 mice were taken for toxicity experiment, and the rest 40 mice for oxidative stress inhibition experiment. Mice in the toxicity experiment were divided into the control group (NC), 4 mg/kg, 20 mg/kg and 100 mg/kg yttrium nitrate groups. Mice in the oxidative stress inhibition experiment were divided into the NC group, 100 mg/kg N-acetylcysteine (NAC) group, 100 mg/kg yttrium nitrate group, 100 mg/kg yttrium nitrate +100 mg/kg NAC group. The number of sperm was calculated using blood cell counting method, and the abnormality rate of sperm was detected by eosin-aniline black method, the apoptosis rate of sperm was detected by flow cytometry, the testicular tissue structure of mouse was detected by HE method, expression levels of IL-1β and TNF-αwere detected using ELISA, while ROS and MDA content in testicular tissue were detected using reagent kit.Results: Compared with the NC group, sperm count in the 100 mg/kg yttrium nitrate group was significantly decreased (P＜0.01), while deformity rate significantly increased (P＜0.001), and sperm apoptosis rate significantly increased (P＜0.01). Compared with the NC group, thinner epithelial thickness, interstitial edema, and vasodilation in the seminiferous tubules were found in mice of the 100 mg/kg yttrium nitrate group, and the arrangement of spermatogenic cells were loose and disordered, with decreased number of spermatogenic cells. Expression levels of IL-1β and TNF-α were higher in the 100 mg/kg yttrium nitrate group than those in the NC control group (P＜0.05). Compared with the NC group, mice in the 100 mg/kg yttrium nitrate group showed a significant increase in testicular ROS (P＜0.01) and MDA levels (P＜0.05). Compared with the 100 mg/kg yttrium nitrate group, mice in the 100 mg/kg yttrium nitrate+100 mg/kg NAC group showed a decrease in ROS and MDA content (P＜0.05), a significant decrease in IL-1βand TNF-α (P＜0.05), a significant increase in sperm count (P＜0.01), and a significant decrease in deformity rate (P＜0.01).Conclusion: Long term exposure to high-dose yttrium may exacerbate testicular oxidative stress, induce orchitis, damage testicular tissue structure, and ultimately lead to a decline in sperm quality.
[1] Wang XD, Wu XL, Zhu ZS, et al. Landscape of RNA editing reveals new insights into the dynamic gene regulation of spermatogenesis[J]. Cell Cycle, 2019, 18(23): 3351-3364.
[2] Jurkowska K, Kratz EM, Sawicka E, et al. The impact of metal loestrogens on the physiology of male reproductive health as a current problem of the XXI century[J]. J Physiol Pharmacol, 2019, 70(3): 337-355.
[3] Yuan HF, Shangguan HF, Zheng Y, et al. Decline in semen concentration of healthy Chinese adults: evidence from 9357 participants from 2010 to 2015[J]. Asian J Androl, 2018, 20: 379-384.
[4] Levine H, Jørgensen N, Martino-Andrade A, et al. Temporal trends in sperm count: a systematic review and meta-regression analysis of samples collected globally in the 20th and 21st centuries[J]. Hum Reprod Update, 2023, 29(2): 157-176.
[5] Tickner BJ, Stasiuk GJ, Duckett SB, et al. The use of yttrium in medical imaging and therapy: historical background and future perspectives[J]. Chemical Society Reviews, 2020, 49(17): 6169-6185.
[6] Guo JD, Yang J, Zhang S, et al. A survey of 16 rare earth elements in the major foods in China[J]. Biomed Environ Sci, 2012, 25(3): 267-271.
[7] Moriyama A, Takahashi U, Mizuno Y, et al. The truth of toxicity caused by yttrium oxide nanoparticles to yeast cells[J]. J Nanosci Nanotechnol, 2019, 19(9): 5418-5425.
[8] Ding YC, Tian YT, Zeng ZY, et al. YCl3 promotes neuronal cell death by inducing apoptotic pathways in rats[J]. Biomed Res Int, 2017, 2017: 2183658.
[9] Xiong L, Huang JY, Wang SH, et al. Yttrium chloride-induced cytotoxicity and DNA damage response via ROS generation and inhibition of Nrf2/PPARγ pathways in H9c2 cardiomyocytes[J]. Arch Toxicol, 2022, 96(3): 767-781.
[10] Hou FP, Huang JY, Qing FR, et al. The rare-earth yttrium induces cell apoptosis and autophagy in the male reproductive system through ROS-Ca2+-CamkII/Ampk axis[J]. Ecotoxicol Environ Saf, 2023, 263: 115262.
[11] Liu N, Chen HG, Li Y, et al. Exogenous metals atlas in spermatozoa at single-cell resolution in relation to human semen quality[J]. Environ Sci Technol, 2023, 57(19): 7358-7369.
[12] Xie XM, Deng T, Duan JF, et al. Exposure to polystyrene microplastics causes reproductive toxicity through oxidative stress and activation of the p38 MAPK signaling pathway[J]. Ecotoxicol Environ Saf, 2019, 190: 110133.
[13] 赖春林, 于巍巍, 钟毅, 等. 几种稀土元素对生殖影响的相关研究进展[J]. 赣南医学院学报, 2019, 39(9): 6.
[14] van Der Zande M, Vandebriel RJ, van Doren E, et al. Distribution, elimination, and toxicity of silver nanoparticles and silver ions in rats after 28-day oral exposure[J]. ACS Nano, 2012, 6(8): 7427-7442.
[15] Shalet SM. Normal testicular function and spermatogenesis[J]. Pediatr Blood Cancer, 2009, 53(2): 285-288.
[16] Wang YM, Yu Z, Zhao ZM, et al. Subchronic toxicity study of yttrium nitrate by 90-day repeated oral exposure in rats[J]. Regul Toxicol Pharmacol, 2017, 90: 116-125.
