麻黄素对仔鼠睾丸组织结构和Bax蛋白、EGF的影响

为探讨麻黄素对各发育期仔鼠（Mus musculus）睾丸组织结构及Bax蛋白和表皮生长因子（epidermal growth factor,EGF)阳性表达的影响,选取60只雄性仔鼠采用递增剂量腹腔连续注射麻黄素,应用生物显微技术观察睾丸组织结构的变化,用免疫组织化学和体视学半定量方法检测Bax蛋白和EGF在睾丸组织中的表达。结果表明麻黄素组仔鼠各发育阶段生精小管直径及上皮厚度明显小于对照组（P < 0.01或P < 0.05）,初级精母细胞直径小于对照组（P < 0.01或P < 0.05）,生精小管上皮各级生精细胞的发生较晚,且排列疏松而凌乱,细胞间空隙多,发育成熟期管腔内成熟精子较少;麻黄素组各发育期仔鼠睾丸中Bax蛋白和EGF的阳性表达与对照组相比显著增强（P < 0.01或P < 0.05）。上述结果说明,麻黄素影响仔鼠睾丸组织的发育,麻黄素对各发育期仔鼠睾丸组织的损伤可能与Bax蛋白和EGF表达的增强有关。     

孕小鼠注射海洛因对仔鼠体重、行为及肺中相关活性物质表达的影响

为了探讨海洛因对仔鼠行为、体重及肺发育中KGF、c-Fos蛋白和Bax蛋白表达的影响,对4组共48例受孕小鼠(Mus musculus)从第8 d开始,每天早晚分别注射0.2 ml浓度为1.0 g/L、1.5 g/L和2.0 g/L的海洛因溶液和等量的生理盐水直到小鼠分娩,观察测量仔鼠行为及体重变化,采用免疫组织化学染色和体视学半定量方法检测15 d胚胎、出生后1 d.7 d、15 d仔鼠的肺中KGF、c-Fos蛋白和Bax蛋白表达情况.结果表明,海洛因影响仔鼠的行为活动,实验组各发育期仔鼠的体重明显低于对照组,海洛因组各发育期仔鼠肺中KGF、c-Fos蛋白和Bax蛋白的表达强度与对照组相比显著增强(P＜0.01或P＜0.05),且随海洛因浓度的增大表达越强,但随着发育的进行,海洛因组仔鼠肺中KGF、c-Fos蛋白和Bax蛋白的阳性表达减弱.海洛因影响仔鼠的行为与体重,海洛因对各发育期仔鼠肺的损伤可能与肺组织中KGF、c-Fos蛋白和Bax蛋白表达的增强有关.     

妊娠及哺乳期母鼠注射麻黄素对仔鼠肝组织TGF-β1和c-Fos表达的影响

为探讨妊娠及哺乳期小鼠(Mus musculus)注射麻黄素后对仔鼠肝组织TGF-β1及c-Fos表达的影响,将30例受孕小鼠随机分为对照组和麻黄素组。麻黄素组小鼠从受孕第3天开始连续腹腔注射6.0 g/L麻黄素溶液直到分娩后15天,每天注射2次,每次0.2 ml;对照组每天2次注射等量的生理盐水。称量检测仔鼠体重和肝重的变化,同时用免疫组织化学方法检测仔鼠肝组织中细胞生长因子TGF-β1和原癌基因c-Fos蛋白表达的变化。麻黄素组仔鼠体重与对照组相比显著降低(P0.05或P0.01),肝体比与对照组相比明显升高(P0.05或P0.01),仔鼠肝组织中TGF-β1和c-Fos蛋白阳性表达强度与对照组相比有不同程度的增强(P0.05或P0.01),表明妊娠及哺乳期小鼠注射麻黄素影响仔鼠肝的发育。     

X射线辐射对仔鼠消化酶活性及胃中Bax和Ghrelin表达的影响

为了探讨X射线辐射对仔鼠胃蛋白酶活性、十二指肠脂肪酶活性及胃中Bax蛋白和Ghrelin表达的影响,对170只仔鼠用不同辐射剂量（0,4,12,20,28 Gy）X射线进行全身辐射,分别在辐射后1,5,10,20 d用比色法检测仔鼠胃蛋白酶活性和十二指肠中脂肪酶活性的变化,用免疫组织化学方法检测胃中Bax蛋白和Ghrelin的表达和分布,并用Image-proplus 5.0专业图像分析软件检测Bax蛋白和Ghrelin在胃中的表达强度。结果表明,X射线辐射影响发育期仔鼠胃蛋白酶和十二指肠脂肪酶的活性以及胃中Bax蛋白和Ghrelin的表达。仔鼠胃蛋白酶活性除在辐射后1 d时高于对照组外,其它辐射后各期均低于对照组,仔鼠十二指肠中脂肪酶活性在辐射后均低于对照组;Bax蛋白主要在仔鼠胃黏膜上皮细胞中表达,其表达水平随辐射剂量的增大而增强;Ghrelin主要在胃内分泌细胞中表达,辐射后其表达水平降低。X射线辐射影响仔鼠消化酶活性,这可能与胃中Bax蛋白和Ghrelin的表达变化有关。     

邻苯二甲酸酯染毒哺乳期母鼠对雄性仔鼠睾丸Leydig细胞形态及功能的影响

目的:观察邻苯二甲酸二乙基己基酯(DEHP)对哺乳期雄性仔鼠睾丸子Leydig细胞(PLC)形态和功能的影响及作用机制。方法:SD孕鼠20只,随机均分为4组(n=5):正常对照组,低剂量组,中剂量组,高剂量组。仔鼠出生第1天起分别以0、10、100、750 mg/(kg·d)DEHP灌胃染毒母鼠,直到仔鼠出生后21 d。用化学发光法检测雄性仔鼠血清睾酮(T)水平;测量体重、睾丸重量、肛生殖器距离(AGD);光镜及电镜下观察睾丸Leydig细胞形态结构;免疫组化方法检测睾丸类固醇激素合成急性调节蛋白(St AR)表达;Real-time PCR法检测睾丸胰岛素样生长因子Ⅰ(IGF-Ⅰ)mRNA的表达。结果:与正常组比较,低剂量组T无明显变化,中、高剂量组血清T水平明显降低(P0.01)。低剂量组睾丸重量增加(P0.05),高剂量组睾丸重量、仔鼠体重明显下降(P0.01);中、高剂量组AGD明显缩短(P0.01)。低剂量组睾丸Leydig细胞明显增生,呈簇状分布;中、高剂量组睾丸Leydig细胞灶区轻度增生,高剂量组部分生精小管生精细胞层次减少、生精细胞凋亡并脱落。电镜观察各给药组Leydig细胞胞浆脂质颗粒减少,线粒体、内质网减少。低剂量组IGF-ⅠmRNA表达增高(P0.05);中、高剂量组睾丸St AR蛋白表达降低(P0.05)。结论:哺乳期染毒DEHP可干扰仔鼠PLC的睾酮合成,St AR蛋白的降低和Leydig细胞的损伤可能是其机制。     

胚胎期接触双酚A对雄鼠睾丸内PCNA和p53表达的影响

目的研究胚胎期接触双酚A(Bisphenol A,BPA)对雄性胎鼠睾丸发育的影响及睾丸内增殖细胞核抗原(Proliferating Cell Nuclear Antigen,PCNA)和p53表达的影响。方法母鼠怀孕后第2天对其灌服双酚A(剂量5,50,100 mg/ml/day),一直持续分娩,F1代雄性小鼠饲养至75日龄,观察BPA对仔鼠成年后睾丸结构和PCNA和p53表达的影响。结果发现BPA处理组睾丸发育受到抑制,曲细精管直径和管腔直径变小(P0.05),管腔内出现大量胞质残余体,部分管腔出现潴留管腔液,支持细胞生长受到抑制,生精细胞排列紊乱,细胞质出现空泡化。免疫组织化学结果显示在BPA处理组,PCNA除了在精原细胞大量表达外,在初级精母细胞中表达量明显升高(P0.05,P0.01),免疫荧光结果显示胚胎期接触BPA导致成年后睾丸内p53蛋白表达量显著升高(P0.05,P0.01)。结论胚胎期接触BPA对雄鼠睾丸发育有着长期的不良影响,可能源于BPA引起细胞的异常增殖和凋亡。     

C1型尼曼–匹克病小鼠雄性不育的睾丸病理研究

该文主要研究C1型尼曼–匹克病小鼠(Npc1~(–/–)小鼠)雄性不育的睾丸病理变化,并进一步探讨Npc1基因对雄性不育的影响。随机选取P60的Npc1~(–/–)和Npc1~(+/+)雄鼠各12只,观察隐睾发生率;然后,随机选取P20、P40和P60的Npc1~(–/–)和Npc1~(+/+)雄鼠睾丸组织,统计睾丸重量并计算睾丸指数, HE染色观察生殖细胞层数并测量生精小管直径, PAS糖原染色观察生殖细胞周期并统计精母细胞在总细胞数中的相对百分比,油红O染色观察间质细胞的脂质存储;最后,随机选择P60的Npc1~(–/–)和Npc1~(+/+)雄鼠睾丸,通过TUNEL染色观察生殖细胞凋亡,并通过Western blot检测凋亡蛋白Cleaved-caspase-3、Cleaved-caspase-9、p53、Bax和Bcl-2的表达水平。结果显示,与Npc1~(+/+)雄鼠相比, Npc1~(–/–)雄鼠均有隐睾发生,睾丸重量和睾丸指数均显著降低(P0.05, P0.001),生殖细胞层数不明显,生精小管管径显著减小(P0.001),生精周期不规律且精母细胞数量显著减少(P0.001),间质细胞的脂质存储显著减少(P0.001);生殖细胞凋亡大幅增加(P0.001), Cleaved-caspase-3、Cleaved-caspase-9、p53、Bax表达量显著升高(P0.001),Bax/Bcl-2比率显著升高(P0.001)。该文结果提示, Npc1基因突变导致隐睾、睾丸结构异常、间质细胞脂质储存减少及生殖细胞凋亡,因此, Npc1基因可能成为研究男性不育的新靶点。     

全氟辛烷磺酸盐对胚胎期大鼠雄性生殖系统的影响

目的:研究全氟辛烷磺酸盐(PFOS)对胚胎期大鼠雄性生殖系统发育的影响.方法:PFOS分别以5、10、20 mg· kg-1·d-1灌胃染毒孕12-19天的SD母鼠,染毒结束后,测量雄性胎鼠体重、身长、睾丸重量、AGD;酶联免疫吸附法检测雄性胎鼠睾丸内睾酮水平;实时荧光定量PCR法测睾丸组织类固醇激素合成急性调节蛋白(StAR)、胰岛素样因子3(INSL3)mRNA的相对表达量.结果:与对照组相比,高剂量染毒组雄性胎鼠体重、体长、AGD长度显著降低(P＜0.01),睾丸重量减轻(P＜0.05);高剂量染毒组雄性胎鼠睾丸中内睾酮水平下降(P＜0.05);高剂量染毒组雄性胎鼠睾丸组织中StAR mRNA的表达量降低(P＜0.05),而中剂量染毒组StAR mRNA和INSL3 mRNA表达量则明显升高(P＜0.01).结论:孕期染毒PFOS对雄性胚胎生殖系统的发育有毒性作用,其机制可能与PFOS影响睾酮合成和INSL3 mRNA的表达有关.     

双峰驼睾丸和隐睾细胞外基质相关蛋白的组织化学特征及超微结构比较

为探索细胞外基质相关蛋白在隐睾双峰驼的分布情况及其组织化学特征,应用电镜技术和多种组织化学方法比较了隐睾和正常睾丸的超微结构,组织化学特点及层粘连蛋白（LN）、Ⅳ型胶原（Col Ⅳ）和硫酸乙酰肝素糖蛋白（HSPG）的分布特征。结果显示：(1)与正常睾丸间质结构相比,光镜下隐睾生精小管发育不全,间质内胶原纤维稀疏,网状纤维分布明显,间质血管及生精小管固有膜PAS及AB-PAS阳性反应较弱。电镜下,隐睾生精上皮基膜明显增生,外围I型胶原纤维较少,管周肌样细胞不典型;间质毛细血管及Leydig细胞周围纤维细胞多见,而正常睾丸在间质毛细血管及Leydig细胞周围多分布有成纤维细胞。(2) 免疫组织化学染色显示,正常睾丸组织的Col Ⅳ、LN及HSPG在Leydig细胞内均为强阳性表达,Col Ⅳ和LN在毛细血管内皮细胞强阳性表达,后者在Sertoli细胞的表达尤为明显,HSPG在精原细胞无表达;隐睾时Col Ⅳ、LN及HSPG在Leydig细胞内阳性表达均明显减弱,Col Ⅳ、LN在管周肌样细胞及毛细血管内皮细胞阳性表达也减弱明显,HSPG在精原细胞较强阳性表达,且在精子细胞呈强阳性表达。免疫组织化学图像分析结果显示,双峰驼正常睾丸组织中Col Ⅳ和LN的分布显著高于隐睾组织（P<0.05）,HSPG检测结果在正常睾丸与隐睾之间无统计学差异（P>0.01）。该研究表明,双峰驼隐睾生精小管发育异常,间质组织中合成胶原纤维的能力下降,睾丸细胞外基质的重要成分Col Ⅳ,LN与正常组差异显著与生精小管及Leydig细胞异常发育有关,而HSPG在隐睾生精上皮的强阳性表达与精原细胞发育不成熟密切相关。     

哺乳期接触双酚A对子代雄鼠睾丸结构及雌激素受体β表达的影响

目的研究哺乳期接触双酚A(BPA)对雄性小鼠睾丸结构及雌激素受体β(ERβ)表达的影响。方法 20只妊娠母鼠,待分娩后随机分为高、中、低剂量组,BPA染毒剂量为100、50、5 mg/(kg.d)和对照组,母鼠分娩后第2天开始每天灌服BPA,仔鼠通过乳汁暴露于BPA,一直持续到第22天断奶,研究其成年后睾丸组织形态学改变,并用免疫组织化学、RT-PCR和Western blot方法研究BPA对其成年后睾丸内ERβ表达的影响。结果睾丸形态学分析表明BPA处理组睾丸发育受到严重影响,生精细胞排列紊乱,支持细胞和各级生精细胞生长受到不同程度的抑制;免疫组化、RT-PCR及Western blot均显示,高、中、低剂量组雄鼠成年后睾丸组织中ERβ的表达均高于对照组,差异均有统计学意义(P<0.05,P<0.01)。结论哺乳期接触BPA影响雄鼠睾丸发育,改变其成年后睾丸形态,提高睾丸组织内ERβ表达,提示BPA可能通过改变雌激素受体表达从而影响睾丸发育。     

运动干预对肥胖大鼠睾丸自噬和凋亡的影响

目的 探讨肥胖对大鼠生精小管结构及自噬和凋亡相关蛋白质的影响,并探讨运动对睾丸自噬和凋亡的影响及其调控机制。方法 将50只6周龄雄性SD大鼠随机分为标准饲养组（SD组,n=20）和高脂饲养组（HFD组,n=30）。HFD组喂养8周建立肥胖大鼠模型,并随机筛选出20只肥胖大鼠进行运动干预。SD组和HFD组分别随机分为标准对照组（CC组）、标准运动组（CE组）、肥胖对照组（OC组）、肥胖运动组（OE组）,每组10只。其中CE组和OE组进行8周中等强度跑台运动干预,60 min/d,5 d/周,其他两组维持原饲养条件。在最后一次运动结束48 h后,将大鼠腹腔麻醉,称重,取大鼠左右两侧睾丸、称量睾丸重量并计算睾丸指数。制作睾丸石蜡切片,利用HE染色法观察睾丸组织结构。采用蛋白质印迹法（Western blot）检测睾丸组织中p62、LC3II、LC3I、BCL-2、Bax和AMPK蛋白表达量并计算LC3II/LC3I比值,采用免疫荧光检测睾丸中LC3和BCL-2蛋白表达位置。结果 与CC组相比,OC组大鼠睾丸指数降低,生精小管直径显著降低（P<0.01）,精子细胞减少,睾丸组织中有脂滴沉...     

急性力竭运动后小鼠肾细胞凋亡水平的变化及牛磺酸的保护作用

为探讨急性力竭运动后小鼠(Mus musculus)肾细胞凋亡水平的时相性变化及牛磺酸对肾的保护作用,将56只雄性小鼠随机分为对照组、力竭运动组(分为运动后即刻组、12h组、24 h组和48 h组)及牛磺酸运动组(分为12h组和24 h组),每小组8只,一次性力竭游泳运动后检测肾细胞凋亡水平、Bcl-2和Bax蛋白表达、一氧化氮(NO)含量及结构型一氧化氮合酶(cNOS)、诱导型一氧化氮合酶(iNOS)活性的变化.结果显示,力竭运动后各组小鼠肾细胞凋亡水平呈先升高后下降的趋势,其中运动后24 h组的凋亡水平达峰值(P＜0.05).与对照组相比,运动各组Bax表达均显著增强(P＜0.05).除运动后即刻组外,运动各组Bcl-2表达显著减弱(P＜0.05).各组Bax/Bcl-2比值显著升高,并在运动后24 h达峰值(P＜0.01),后出现下降趋势.小鼠力竭游泳后24 h和48 h肾组织NO含量显著高于对照组(P＜0.05),同时iNOS活性升高(P＜0.01),cNOS活性无显著性变化.相比同时刻运动组,牛磺酸运动组小鼠肾细胞凋亡水平、Bax表达及Bax/Bcl-2比值、iNOS活性显著降低(P＜0.05),Bcl-2表达显著升高(P＜0.05).以上结果表明,急性力竭运动可导致肾细胞凋亡的发生,iNOS、Bax、Bcl-2水平及Bax/Bcl-2比值可能在肾细胞凋亡的发生过程中发挥重要的介导作用.牛磺酸可通过调控iNOS活性及Bax/Bcl-2比值,抑制急性力竭运动后小鼠肾细胞凋亡的发生.     

Upregulation of AP1 by tertiary butyl hydroperoxide induced oxidative stress and subsequent effect on spermatogenesis in mice testis

Oxidative stress is detrimental to sperm function and a significant factor in the etiology of male infertility. Present study evaluates the effect of ter butyl hydroperoxide (TBHP)-induced oxidative stress on the spermatogenic process and cell number in the seminiferous tubules. Intraperitoneal injection of TBHP (84 μmol TBHP/100 g body weight) for 2 weeks to male Balb/c mice resulted in enhanced lipid peroxidation (P < 0.0001) decrease in reduced glutathione (P < 0.0001) and increase in the oxidized glutathione levels (P = 0.007) in the testis. Status of spermatogenesis after the treatment was assessed by the quantitative methods of germ cell evaluation in the seminiferous tubules. A significant decrease in the number of young spermatids (P = 0.0003) and pachytene cells (P = 0.022) was observed. A marked reduction was also seen in the mature spermatid number (P < 0.0001). An increase in testicular mRNA levels of redox-regulated cjun (P = 0.008) and cfos (P = 0.0006) subunits of activator protein 1 (AP1) was observed after TBHP treatment. Evaluation of AP1 regulated antioxidant enzymes in the testis revealed an increase in γ-glutamyl cysteine synthetase (GCS) mRNA expression (P = 0.001). These results suggest a potential role of AP1 in oxidative stress-mediated meiotic and post meiotic changes in the spermatogenic process and regulation of cell number in male reproductive system.     

Early prepubertal testis criteria, seminiferous epithelium and hormone concentrations as related to testicular development in beef bulls

The present study was conducted to evaluate testis size, spermatogenesis and hormone concentrations before and when peripheral testosterone reached 1 ng/ml as related to further gonad development of beef bulls (n=28). Blood samples were taken weekly starting at 10 weeks (wk) and when testosterone reached 1 ng/ml (AGE1), the left testis was surgically excised. From AGE1 until 54 wk, blood samples were collected to follow basal and GnRH-stimulated hormone profiles. At 54 wk, the second testis was removed. Testosterone reached 1 ng/ml at 20±0.6 wk and, at this developmental state, the seminiferous tubules occupied 57±1.1% of the testis parenchyma. At this phase, 79.3±1.4% of tubule sections had no germ cells and only 2.4±0.3% of the remaining tubules had spermatocytes as the most advanced germ cell type. Also at AGE1, testis size was correlated with the number of Sertoli cells per testis (r=0.67; P<0.05), but not (P>0.05) with the percentage of tubules with germ cells. There was a consistent increase in body weight and testis size throughout the study showing that hemicastration did not impair the development of the bulls. At 54 wk, seminiferous tubules represented 76±0.7% of the testis parenchyma and 72.3±1.7% of tubule sections were found with either round or elongated spermatids. Quantitative criteria of spermatogenesis in the second testis (excised at 54 wk) were not correlated (P>0.05) with the percentage of seminiferous tubules with germ cells in the first testis (excised at AGE1). As determined by regression analysis, testis diameter measured between 30 and 44 wk (AVTD) was associated with AGE1 and testis diameter averaged at 12 wk and AGE1 (R(2)=0.77; P<0.01). Also, AVTD was related to AGE1, testis diameter at 12 wk and concentrations of 17β-estradiol (estradiol; basal+GnRH-stimulated) averaged between 10 wk and AGE1 (R(2)=0.79; P<0.01). Yearling testis weight, in turn, was linked to AGE1 and testis weight at AGE1 (R(2)=0.49, P<0.01). In conclusion, early detection of 1 ng of testosterone/ml, larger testis size and greater estradiol before and at that developmental period positively relate to future testis attributes. When testosterone reached 1 ng/ml, the seminiferous tubules had Sertoli cells, spermatogonia and a few spermatocytes and events occurring before and at that phase are potential markers of testis growth and sperm-producing capacity of sires.     

Crlz-1 Is Prominently Expressed in Spermatogonia and Sertoli Cells during Early Testis Development and in Spermatids during Late Spermatogenesis

The expression of the Crlz-1 gene in mouse testis, where it was found to be expressed most highly among the tested mouse organs, was analyzed spatiotemporally by employing RT-PCR and in situ hybridization techniques with the aid of immunohistochemistry and/or immunofluorescence methods. In 1-week-old neonatal testis, Crlz-1 was strongly expressed in the spermatogonia and Sertoli cells in its seminiferous cord. In 2- to 3-week-old prepubertal testis, where Sertoli cells cease to proliferate, Crlz-1 expression dropped and remained weakly at the rim layer of seminiferous cords and/or tubules, where spermatogonia are present. In the adult testis at 12 weeks after birth, Crlz-1 was expressed mainly in the spermatids near the lumen of seminiferous tubules. In a further in situ hybridization of Crlz-1 in the 12-week-old adult testis with hematoxylin nuclear counterstaining, Crlz-1 was mainly expressed at step 16 of spermatids between stages VII and VIII of seminiferous tubules as well as in their residual bodies at stage IX of seminiferous tubules.     

Upregulation of heat shock protein 32 in Sertoli cells alleviates the impairments caused by heat shock-induced apoptosis in mouse testis

Heat stress results in apoptosis in testicular germ cells. A small heat shock protein (hsp), hsp32, is induced by heat stress in the testis, but little is known about its definitive function in physiological processes. To clarify the underlying role of hsp32, hsp32 expression and related signals in the heat shock pathway were analysed in mouse testes and Sertoli cells after heat stress in vivo and in vitro; meanwhile, expression of hsp32 was silenced only in the Sertoli cells using three different small interfering RNAs (siRNAs) to further verify the functional role of hsp32 in Sertoli cells, and hsp32-derived carbon monoxide (CO) contents in cultured media were analysed to clarify whether hsp32-derived CO involve in the apoptosis regulation mechanisms. The results from the in vivo experiment showed that the high expression levels of hsp32 (P?<?0.05) were observed whether chronic, moderate or acute, transient heat exposure. The in vitro experiment showed that acute, transient heat exposure resulted in increases in Sertoli cells apoptosis (P?<?0.01), the expression of hsp32 and caspase-3 activity; hsp32-siRNA knockdown of hsp32 expression resulted in upregulated apoptosis (P?<?0.01) and caspase-3 activity (P?<?0.01) in the Sertoli cells and hyperthermia increases CO (P?<?0.01) release by Sertoli cells. The results suggested that upregulating hsp32 in Sertoli cells inhibits caspase-3 activity and alleviates heat-induced impairments in mouse testis; hsp32-derived CO may involve in the regulation mechanism.     

Infection of SARS-CoV-2 causes severe pathological changes in mouse testis

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has affected more than 600 million people worldwide. Several organs including lung, intestine, and brain are infected by SARS-CoV-2. It has been reported that SARS-CoV-2 receptor angiotensin-converting enzyme-2 (ACE2) is expressed in human testis. However, whether testis is also affected by SARS-CoV-2 is still unclear. In this study, we generate a human ACE2 (hACE2) transgenic mouse model in which the expression of hACE2 gene is regulated by hACE2 promoter. Sertoli and Leydig cells from hACE2 transgenic mice can be infected by SARS-CoV-2 pseudovirus in vitro, and severe pathological changes are observed after injecting the SARS-CoV-2 pseudovirus into the seminiferous tubules. Further studies reveal that Sertoli and Leydig cells from hACE2 transgenic mice are also infected by authentic SARS-CoV-2 virus in vitro. After testis interstitium injection, authentic SARS-CoV-2 viruses are first disseminated to the interstitial cells, and then detected inside the seminiferous tubules which in turn cause germ cell loss and disruption of seminiferous tubules. Our study demonstrates that testis is most likely a target of SARS-CoV-2 virus. Attention should be paid to the reproductive function in SARS-CoV-2 patients.     

Characterization of transgenic mice expressing EGFP under the control of the monkey 20α-hydroxysteroid dehydrogenase promoter

To directly assess the molecular function of the monkey 20α-hydroxysteroid dehydrogenase(20α-HSD) promoter, we generated transgenic mice(tg) expressing enhanced green fluorescent protein(EGFP) under control of this promoter. We demonstrated that prostaglandin F2α induced 20α-HSD promoter activity in CHO cells in a dose-dependent manner. Furthermore, forskolin treatment markedly reduced 20α-HSD promoter activity, and prolactin exhibited weak inhibitory activity. The transgenic mouse obtained one positive founder male. The transgene was propagated in 10 successive generations without any notable defects to the progeny. EGFP and 20α-HSD in the tg mice were colocalized in the luteal cells of the ovary during late pregnancy. Strong EGFP and 20α-HSD protein signals were also detected in the adult testis. Immunohistochemical analysis revealed high EGFP levels in the seminiferous epithelium, whereas 20α-HSD was expressed in the seminiferous tubules. Our data suggest that the ovaries in monkey and mouse exhibit similar expression patterns of 20α-HSD during pregnancy. However, the expression pattern of EGFP in tg mice testis slightly differed from that of the endogenous 20α-HSD. Further investigation is required to elucidate the functional mechanisms underlying regulation of the monkey 20α-HSD promoter in the tg mice.     

Piwil2 及Stat3、Bcl-2 蛋白在雄性不育小鼠 睾丸组织中表达

本研究主要是探讨Piwil2、Stat3、Bcl-2蛋白在不育的雄性小鼠中的表达量及三者之间的表达位置相关性。取雄性昆明种小鼠60只,随机分为实验组与对照组,每组30只。实验组采用雷公藤多苷药物灌胃造小鼠不育模型28 d;对照组按照同样剂量的生理盐水进行灌胃,持续时间及频次同实验组。造模后将两组雄性小鼠分别与雌性小鼠交配;再处死雄性小鼠取出两组的睾丸组织,采用免疫组织化学染色法和蛋白印迹检测法分别检测样本中Piwil2、Stat3及Bcl-2蛋白的表达状况。将实验组与对照组的检测结果进行比较,观察两组的蛋白表达差异性及三个蛋白表达的相关性。H.E染色显示,实验组小鼠睾丸组织生精小管结构与对照组相比,明显被破坏,精原细胞及初次级精母细胞数量明显减少,结合与雌鼠交配后受精能力明显下降的结果,说明不育造模成功。免疫组化(IHC)染色结果显示,实验组Piwil2、Stat3及Bcl-2蛋白的染色程度及阳性细胞数均明显低于对照组(P 0.01)。Western Blot结果同样显示,三种蛋白在实验组的表达量明显低于对照组(Piwil2蛋白P 0.05,Stat3蛋白P 0.05,Bcl-2蛋白P 0.01)。本研究说明,Piwil2、Stat3及Bcl-2蛋白在雄性不育小鼠中表达量均显著降低,这三个蛋白对小鼠精子生成及小鼠不育的发生起到重要调节作用。