Molecular mechanism of epididymal protease inhibitor modulating the liquefaction of human semen

Aim： To study the molecular mechanism of epididymal protease inhibitor （Eppin） modulating the process of prostate specific antigen （PSA） digesting semenogelin （Sg）. Methods： Human Sg cDNA （nucleotides 82-849） and Eppin cDNA （nucleotides 70-423） were generated by polymerase chain reaction （PCR） and cloned into pET-100D/TOPO. Recombinant Eppin and Sg （rEppin and rSg） were produced by BL21 （DE3）. The association of Eppin with Sg was studied by far-western immunoblot and radioautography. In vitro the digestion of rSg by PSA in the presence or absence of rEppin was studied. The effect of anti-Q20E （N-terminal） and C-terminal of Eppin on Eppin-Sg binding was monitored. Results： Eppin binds Sg on the surface of human spermatozoa with the C-terminal of Eppin （amino acids 75-133）. rSg was digested with PSA and many low molecular weight fragments were produced. When rEppin is bound to rSg, then digested by PSA, incomplete digestion and a 15-kDa fragment results. Antibody binding to the N-terminal of rEppin did not affect rSg digestion. Addition of antibodies to the C-terminal of rEppin inhibited the modulating effect of rEppin. Conclusion： Eppin protects a 15-kDa fragment of rSg from hydrolysis by PSA.     

Effect of NO on spontaneous acrosome reaction in AsAb positive rat spermatozoa

Objective: To explore the effect of NO on the spontaneous acrosome reaction in antisperm antibody (AsAb) positive rat spermatozoa. Methods: The rat model of AsAb was set up by artificial immunization. The level of AsAb in blood serum was determined by TAT and ELISA. Rat spermatozoa was visualized by staining the acrosome with Coomassie brilliant blue. The NO concentration in rat spermatozoa was assayed by HPLC. Results: The percentage of acrosome reaction, NO concentration, superoxide dismutase (SOD) and Na~ -K~ ATPase activity in AsAb positive rat spermatozoa were significantly decreased compared with the control group. Low dose of NO (SNP 10~(-9)～10~(-8) mol/L) increased the percentage of acrosome reaction and SOD activity, but had no effect on Na~ -K~ ATPase activity. High dose of NO (SNP 10~(-6)～10~(-4) mol/L) decreased the three items. Conclusion: The decrease in acrosome reaction in positive AsAb rat spermatozoa might be related to a decrease in NO and increase in O_2. (the SOD activity was decr     

Evaluation of deoxyribonuclease activity in seminal plasma of ejaculated chicken semen

Aim: To confirm the stability of exogenous genes in the generation of transgenic chickens using ejaculated chicken sperm, the deoxyribonuclease (DNase) activity was evaluated in the seminal plasma of ejaculated semen and the stability of DNA was examined by adding lipofection reagents. Methods: A PCR fragment (249 bp) of pEGFPN-1 vector was used as the DNA substrate and was incubated with the seminal plasma at 40℃for 30 min. Then, the whole reaction solution was subjected to agarose gel electrophoresis and the DNA size was evaluated under UV light.Results: The DNA substrate was completely diminished after incubation with seminal plasma. However, the sub-strate was intact after incubation with heat-treated seminal plasma or incubation with seminal plasma in the presence of 0.5 mmol/L-5 mmol/L EDTA. The substrate was stabilized in the seminal plasma by the addition of commercially available lipofection reagents. Conclusion: The DNase activity is present in the seminal plasma of ejaculated chicken semen. However, DNA is stable in the liposomal-DNA complex. ( Asian JAndro12003 Sep; 5: 213-216)     

重组人前列腺特异性抗原的原核表达、纯化与鉴定

目的:用分子克隆技术体外制备人前列腺特异性抗原(PSA)重组蛋白,并对其活性进行鉴定。方法:用分子克隆技术从前列腺癌cDNA文库中扩增PSAcDNA,再将cDNA和准备插入的质粒载体PET-12α分别用限制性内切酶NdeⅠ和BamHⅠ消化,然后用T4连接酶将两者连接,序列正确的阳性克隆转染BL21(DE3)大肠埃希菌,诱导表达重组人PSA蛋白,从细菌包涵体中纯化PSA蛋白,再用小剂量胰岛素激活PSA活性,观察活化的PSA是否分解其变色底物S-2586和天然底物精囊蛋白Semenogelin(Sg)。结果:利用原核表达技术得到了重组人PSA,在胰岛素作用下PSA被激活,活性PSA水解其天然底物Sg和变色底物S-2586。结论:用基因克隆方法体外获得的重组人PSA蛋白可表现与天然PSA同样的丝氨酸蛋白酶活性和功能。     

Roles of tumor necrosis factor alpha on sperm acrosin activity and acrosome reaction

Aim: To study the roles of tumor necrosis factor alpha (TNF-a)on the sperm acrosin activity and acrosome reaction. Methods:The sperm acrosin activity was tested by the method of BAEE/ADH Unity and the acrosome reaction by the Triple-stain technique. Results: TNF-a decreased the sperm acrosin activityand acrosome reaction (P＜0.01, P＜0.01, respectively);     

趋化因子2对乳腺癌细胞MCF-7趋化活性及趋化因子5mRNA表达的影响

Objective To observe the effects of chemokine 2 (CCL2) on the expression of chemokine 5 ( CCL5) mRNA and chemotactic activity of MCF-7 cells. Methods MCF-7 cells were treated with different concentrations of CCL2, the expression of CCL5 mRNA was detected by using real-time fluorescence quantitative polymerase chain reaction ( RTFQ-PCR), and the chemotactic activity of MCF-7 was measured by using chemotaxis chamber method. Results When the concentration of exogenous CCL2 was 200 μg/L, the MCF-7 cells expressed the highest CCL5 mRNA (15. 22 ± 2. 3, P ＜0. 01). With the prolongation of CCL2 action time, the expression levels of CCL5 mRNA were increased. There was a positive correlation between the chemotactic activity of MCF-7 cells and the concentration of CCL2. When the concentration of exogenous CCL2 was 300 μg/L, the number of penetrating cells was the greatest (88.00 ±11. 53, P ＜0. 01). With the prolongation of CCL2 action time, the chemotactic activity of MCF-7 cells was enhanced. When the action time was 30 h, the number of penetrating cells was the greatest (81.00 ±9. 54, P ＜ 0.05 ). Conclusion Exogenous CCL2 could increase the expression of CCL5 mRNA and the chemotactic activity of MCF-7 cells.     

趋化因子2对乳腺癌细胞MCF-7趋化活性及趋化因子5mRNA表达的影响

Objective To observe the effects of chemokine 2 (CCL2) on the expression of chemokine 5 ( CCL5) mRNA and chemotactic activity of MCF-7 cells. Methods MCF-7 cells were treated with different concentrations of CCL2, the expression of CCL5 mRNA was detected by using real-time fluorescence quantitative polymerase chain reaction ( RTFQ-PCR), and the chemotactic activity of MCF-7 was measured by using chemotaxis chamber method. Results When the concentration of exogenous CCL2 was 200 μg/L, the MCF-7 cells expressed the highest CCL5 mRNA (15. 22 ± 2. 3, P ＜0. 01). With the prolongation of CCL2 action time, the expression levels of CCL5 mRNA were increased. There was a positive correlation between the chemotactic activity of MCF-7 cells and the concentration of CCL2. When the concentration of exogenous CCL2 was 300 μg/L, the number of penetrating cells was the greatest (88.00 ±11. 53, P ＜0. 01). With the prolongation of CCL2 action time, the chemotactic activity of MCF-7 cells was enhanced. When the action time was 30 h, the number of penetrating cells was the greatest (81.00 ±9. 54, P ＜ 0.05 ). Conclusion Exogenous CCL2 could increase the expression of CCL5 mRNA and the chemotactic activity of MCF-7 cells.     

Short-term effects of obestatin on hexose uptake and triacylglycerol breakdown in human subcutaneous adipocytes

AIM To study complete dose-dependent effects of obestatin on lipolytic and glucose transport activities in human adipocyte preparations highly responsive to insulin.METHODS Adipocytes were prepared by liberase digestion from subcutaneous abdominal adipose tissue obtained from overweight subjects undergoing plastic surgery. The index of lipolytic activity was the glycerol released in the incubation medium, while glucose transport was assessed by [~3H]-2-deoxyglucose uptake assay.RESULTS When tested from 0.1 nmol/L to 1 μmol/L, obestatin did not stimulate glycerol release; it did not inhibit the lipolytic effect of isoprenaline and did not alter the insulin antilipolytic effect. Obestatin hardly activated glucose transport at 1 μmol/L only. Moreover, the obestatin stimulation effect was clearly lower than the threefold increase induced by insulin 100 nmol/L.CONCLUSION Low doses of obestatin cannot directly influence lipolysis and glucose uptake in human fat cells.     

Gossypol inhibits proliferation of endometrioma cells in culture

Aim： To evaluate the anti-proliferative activity and mitochondrial toxicity of gossypol in endometrioma cells maintained in short-term cultures. Methods： （A） Three endometrioma cell lines from patients were treated with 25 or 50 nmol/L gossypol for up to 12 days. The effect of gossypol on the cell growth was recorded. （B） A phosphorescence oxygen analyzer was used to determine the effects of gossypol on mitochondrial oxygen consumption of six endometrioma cell lines from patients. （C） Cellular gossypol accumulations in three endometrioma cell lines from patients were measured by high-pressure liquid chromatography. Results： Proliferation of the endometrioma cells was inhibited by 25 and 50 nmol/L gossypol. Respiration of the endometrioma cells was inhibited by 10 μmol/L gossypol. Cellular gossypol was detected in the endometrioma cell lines that were treated for 24 h with l0 and 0.3 μmol/L gossypol. Conclusion： Gossypol invokes a potent toxicity on cultured endometrioma cells.     

趋化因子2对乳腺癌细胞MCF-7趋化活性及趋化因子5mRNA表达的影响

目的 观察趋化因子2(CCL2)对MCF-7表达趋化因子5(CCL5)mRNA的影响,并观察CCL2对MCF-7趋化活性的影响.方法 使用不同浓度的CCL2作用于MCF-7细胞,通过实时荧光定量聚合酶链反应(RTFQ-PCR)测定不同时间CCL5 mRNA的表达,并使用趋化小室法检测CCL2作用下MCF-7趋化活性的改变.结果 当外源性CCL2浓度为200μg/L时,MCF-7中CCL5 mRNA相对表达量最大(15.22±2.32)(P＜0.01),随着作用时间的延长,CCL5 mRNA表达量增加;MCF-7的趋化活性与CCL2浓度呈正相关,当CCL2浓度为300μg/L时,穿膜细胞数最多(88.00±11.53)(P＜0.01);MCF-7的趋化活性与CCL2作用时间呈正相关,当CCL2作用时间为30 h时,穿膜细胞数最多(81.00±9.54)(P＜0.05).结论 加入外源性CCL2,MCF-7中CCL2 mRNA表达量增加,MCF-7趋化活性增强.

Abstract：

Objective To observe the effects of chemokine 2 (CCL2) on the expression of chemokine 5 ( CCL5) mRNA and chemotactic activity of MCF-7 cells. Methods MCF-7 cells were treated with different concentrations of CCL2, the expression of CCL5 mRNA was detected by using real-time fluorescence quantitative polymerase chain reaction ( RTFQ-PCR), and the chemotactic activity of MCF-7 was measured by using chemotaxis chamber method. Results When the concentration of exogenous CCL2 was 200 μg/L, the MCF-7 cells expressed the highest CCL5 mRNA (15. 22 ± 2. 3, P ＜0. 01). With the prolongation of CCL2 action time, the expression levels of CCL5 mRNA were increased. There was a positive correlation between the chemotactic activity of MCF-7 cells and the concentration of CCL2. When the concentration of exogenous CCL2 was 300 μg/L, the number of penetrating cells was the greatest (88.00 ±11. 53, P ＜0. 01). With the prolongation of CCL2 action time, the chemotactic activity of MCF-7 cells was enhanced. When the action time was 30 h, the number of penetrating cells was the greatest (81.00 ±9. 54, P ＜ 0.05 ). Conclusion Exogenous CCL2 could increase the expression of CCL5 mRNA and the chemotactic activity of MCF-7 cells.     

附睾蛋白酶抑制剂Eppin的研究进展

附睾蛋白酶抑制剂Eppin是一种睾丸和附睾特异性分泌的蛋白质,精液中含量极为丰富,精子表面大量存在,用重组Eppin免疫的猴子出现不育,Eppin有望成为人类有效的可逆性的免疫避孕疫苗。现就Eppin基因及其蛋白质结构功能特点,Eppin引起免疫性不育的分子机制以及Eppin调控PSA水解精囊蛋白Semenogelin的研究进展进行了综述。     

壬基酚和镉离子在体外对小鼠精子顶体反应的影响

目的:研究壬基酚和镉离子在体外对小鼠精子顶体反应(AR)的影响。方法:从小鼠的输精管获得精子,体外培养使精子获能,加30μmol/L的A23187诱导精子顶体反应,然后使用不同浓度的壬基酚(10、20、30、60、100μmol/L),或者镉离子(500、2500、5000μmol/L)处理,对照组使用相应的载体溶剂处理。用FITC-PSA荧光染色法分析精子顶体反应。结果:当壬基酚浓度<30μmol/L时,小鼠精子顶体反应率与对照组比较没有显著差异(P>0.05),而当壬基酚浓度>60μmol/L时能够显著地抑制小鼠精子顶体反应发生率(P<0.01),并且观察到精子存活率随着壬基酚浓度增加而降低。与壬基酚作用不同,用镉离子对小鼠精子进行处理,在所选浓度内(500~5 000μmol/L)均对精子顶体反应无显著影响(P>0.05),且精子存活率与镉离子浓度变化无关。结论:壬基酚与镉离子对小鼠精子发生的作用是通过不同的途径来实现的,前者可以直接抑制顶体反应,而后者则与精子顶体反应无关。     

腺病毒介导HSV-TK／GCV自杀基因系统靶向性治疗前列腺癌实验研究

目的观察腺病毒介导单纯疱疹病毒胸苷激酶基因／丙氧鸟苷（HSV-TK／GCV）自杀基因系统在人端粒酶逆转录酶（hTERT）启动子调控下对人前列腺癌细胞的靶向性体外杀伤效应。方珐利用不同感染复数（MOI）的重组腺病毒携带增强型绿色荧光蛋白（EGFP）基因感染前列腺癌细胞LNCaP和人成纤维细胞MRC-5,荧光显微镜下观察其感染效率;利用携带不同启动子的重组腺病毒Ad-hTERT-HSV／TK以及Ad-CMV-HSV／TK感染LNCaP和MRC-5细胞,加入不同浓度GCV,MTT法观察受转染细胞的存活率。结杲重组腺病毒Ad-hTERT-EGFP能特异地转染LNCaP,其转染效率随重组病毒的MOI增加而升高（P〈0.01）,MOI为1时转染率为8.3％,MOI为1000时转染率达100％;应用GCV处理后,Ad-CMV-HSV／TK对LNCaP和MRC-5细胞均有杀伤作用,而Ad-hTERTp-HsV／TK只杀伤LNcaP（P〈0.001）,随着MOI和GCV浓度的增加,LNCaP细胞存活率明显降低（P〈0.01）,MOI为1和GCV浓度为1μmol／L时存活率为95.4％,MOI为100和GCV浓度为1000μmol／L时存活率仅为6.1％,并有旁观者效应。结论重组腺病毒携带EGFP报告基因可准确、简便地确定转染效率;hTERT启动子调控的重组腺病毒介导的HSV-TK／GCV自杀基因系统对人前列腺癌细胞有靶向杀伤作用。     

4′-羰基乙氧苯基4-胍基苯甲酸酯盐酸盐对人精子顶体蛋白酶活性的影响

应用明胶底物膜方法测定了4′-羰基乙氧苯基4-胍基苯甲酸酯盐酸盐(CEGB)对生育男子精子的明胶水解(顶体蛋白酶)活性的抑制作用。实验结果表明当底物膜中 CEGB 的浓度逐渐增加时,精子的晕圈形成率(SHF)逐渐减少,平均晕圈直径(MHD)和平均溶解面积(MLA)都逐渐缩小;当CEGB 的浓度增加到6μmol/L 时则可完全抑制精子的晕圈形成。结果表明 CEGB 能够抑制人精子的明胶水解活性。     

Expression, purification, and characterization of active recombinant prostate-specific antigen in Pichia pastoris (yeast)

BACKGROUND: Prostate-specific antigen (PSA), a member of the kallikrein family of serine proteases, is a chymotrypsin-like glycoprotein produced by the prostate epithelium. Elevated serum PSA (> 4 ng/ml) is a tumor marker for prostatic cancer and benign prostatic hypertrophy; increasing serum PSA over time is indicative of metastatic disease. It has been suggested that PSA may contribute to tumor metastasis through degradation of extracellular matrix glycoproteins, as well as cleavage of IGF binding protein-3, a modulator of IGF-1. To elucidate the role of PSA in the development and progression of prostatic cancer, it is necessary to have a reliable, cost-effective source of enzymatically active protein. Previous efforts to express recombinant PSA (rPSA) produced inactive proPSA, or mixtures of active and inactive PSA requiring activation by removal of the propeptide. We describe the expression of active recombinant mature PSA in yeast. METHODS: Stable chromosomal integration of a construct consisting of the yeast alpha-factor signal sequence preceding the mature PSA sequence resulted in secretion of rPSA. The rPSA was purified from the yeast cell culture supernatant to homogeneity by strong cation-exchange chromatography, and characterized by SDS-PAGE, Western analysis, electrospray mass spectrometry, N-glycanase digestion, N-terminal amino acid sequencing, and inactivation by a PSA-specific inhibitor. RESULTS: We report the production of active, mature rPSA in Pichia pastoris. Two forms of rPSA varying slightly in glycosylation were identified. The specific activity of the rPSA was equal to that of human seminal plasma PSA (0.56 micromol/min mg) as determined using a chromogenic substrate. CONCLUSIONS: Large-scale production of active rPSA will be useful in the exploration of PSA effects on tumor cell proliferation, migration and metastasis. In addition, a large supply of enzyme should facilitate the discovery of novel inhibitors for in vitro and in vivo evaluation, and may provide a reproducible source of rPSA for use as a standard in diagnostic testing.     

不同浓度白藜芦醇对破骨细胞分化的影响及自噬的作用

目的研究不同浓度白藜芦醇(RSV)对破骨细胞分化的影响及自噬在其中的作用。方法RANKL诱导RAW264.7细胞分化过程中,加入不同浓度(0、0.1、0.5、1、5及10μmol/L)RSV,CCK-8检测干预后12、24、48、72 h时的细胞活力;TRAP染色观察破骨细胞分化程度。加或不加入3-甲基嘌呤(3-MA)抑制自噬,RT-PCR检测破骨分化相关标志物TRAP、MMP-9、CTSK和自噬相关标志物LC3、Beclin-1、P62的mRNA表达情况;Western blot检测自噬相关蛋白LC3II/I、Beclin-1、P62的表达情况。结果RANKL诱导分化过程中,细胞增殖活力提高,加入0.1~10μmol/L的RSV,细胞活力先上升后下降,在0.5μmol/L时达到最大;0.1μmol/L和0.5μmol/L的RSV能提高TRAP染色阳性的破骨细胞数和TRAP、MMP-9、CTSK、LC3、Beclin-1、P62的mRNA表达,自噬相关蛋白LC3II/I和Beclin-1也增加,P62的蛋白表达则减少;而1~10μmol/L RSV随浓度升高相关mRNA及蛋白LC3II/I和Beclin-1的表达减少,P62的蛋白表达增加;加入3-MA后,相关mRNA及蛋白LC3II/I和Beclin-1的表达减少,P62的蛋白表达增加。结论RSV浓度在0.1~10μmol/L范围内,破骨细胞分化和自噬水平先升高后降低,抑制自噬可以抑制破骨细胞的分化。白藜芦醇影响破骨细胞分化可能部分是通过调节自噬发挥作用。     

选择性Cox-2抑制剂Celebrex对人胆囊癌GBC-SD细胞系生长的抑制作用

目的: 探讨选择性环氧合酶-2(Cox-2)抑制剂Celebrex对体外培养的人胆囊癌GBC-SD细胞系增殖的影响。方法:采用MTT比色法检测Celebrex对细胞系生长的影响;TUNEL染色法观察细胞凋亡指数,并用流式细胞仪定量分析；透射电镜和荧光显微镜检测细胞凋亡。结果:Celebrex抑制GBC-SD细胞系的生长呈剂量依赖性;40,80,120,160μmol/L浓度的Celebrex对GBC-SD细胞的生长抑制率分别是18.77%,25.32%,46.58%和52.19%（P<0.01）。流式细胞仪定量分析在40,80,120,160μmol/L浓度下的细胞凋亡率分别为（8.51±1.44）%,（12.40±0.87）%,（26.37±1.72）%和（43.21±0.39）%，与对照组（4.87±0.55）%比较有显著的统计学差异；各组间两两比较差异亦有显著性(均P<0.01)。透射电镜和荧光显微镜下能观察到胞核浓缩、碎裂以及凋亡小体的形成。结论:Celebrex 可以有效地抑制人胆囊癌GBC-SD细胞系的增殖并诱导其凋亡。     

重组质粒pEGFP-c1-FLT3L的构建及鉴定

目的：构建重组质粒pEGFP-c1-FLT3L并鉴定,为下一步利用纳米载体介导FL基因移植作用于结肠癌细胞的体内实验奠定基础。方法：应用基因合成和克隆技术构建重组质粒pEGFP-c1-FLT3L,并进行酶切鉴定及序列测定,以检测其核苷酸序列与设计的是否完全一致。结果：重组质粒pEGFP-c1-FLT3L经酶切鉴定分析,琼脂糖凝胶电泳鉴定可见清晰地切出与FLT3L基因大小相符的片段并与DNAmarker相符,同时进行序列测定,证实其核苷酸序列与设计完全一致。结论：成功构建重组质粒pEGFP-c1-FLT3L并得到正确鉴定,为下一步结肠癌的基因治疗打下实验基础。