Effects of VEGF and bFGF on Proliferation and Production of Steroids and Nitric Oxide in Porcine Granulosa Cells

Ovarian angiogenesis, which is currently considered to be of crucial importance in controlling the growth of developing follicles, is a physiological process driven by a variety of angiogenic factors. Among these, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) have been recognized as key players in promoting cell growth and differentiation. Porcine granulosa cells from small (<3 mm), medium (3–5 mm) and large (>5 mm) follicles were seeded at different densities in DMEM:Ham's F12 (1:1) with or without different concentrations of VEGF or bFGF. After 48 h of culture, media were assayed for oestradiol (E2) 17β, progesterone (P4), nitric oxide (NO) and VEGF levels; in addition, cell proliferation was evaluated by ³H‐thymidine incorporation assay. Both bFGF and VEGF effects on E2 and P4 production by cultured granulosa cells resulted to be dependent on follicle size. The bFGF was always ineffective in modulating cell proliferation, while VEGF exerted an inhibitory effect on the proliferation in the small follicle group and a stimulatory one in the medium and large follicle groups. The bFGF consistently reduced NO levels in culture media. The VEGF appeared to be ineffective in modifying NO production in the small follicle group, while it was stimulatory in the medium follicle group and inhibitory in the large follicle group. Basal VEGF production was higher in cells from the large follicle as compared with the small and medium follicle groups, and it was unaffected by bFGF. These results suggest that VEGF plays a modulatory role in granulosa cell functional activity and it is possibly involved in the regulation of follicle growth; on the contrary, bFGF does not appear to represent a significant regulatory factor in our cellular model, except for an inhibitory action on the production of NO, whose anti‐angiogenic properties need to be further substantiated.     

Angiogenic Activity of Swine Granulosa Cells: Effects of Hypoxia and the Role of VEGF

Veterinary Research Communications -     

The Influence of Opioid Peptides on Steroidogenesis in Porcine Granulosa Cells

The present studies were undertaken to examine the influence of mu (beta-endorphin, DAMGO, FK 33-824), delta (met-enkephalin, leu-enkephalin, DPLPE) and kappa opioid receptor agonists (dynorphin A, dynorphin B, U 50488) used at different doses (1-1000 nM) alone and in combination with LH (100 ng/ml) on steroidogenesis in porcine granulosa cells derived from large follicles. The effects of mu, delta and kappa receptor agonists on both basal and LH-induced progesterone (P4) secretion were negligible. Agonists of mu opioid receptors reduced basal androstenedione (A4), testosterone (T) and oestradiol (E2) release. Co-treatment with LH entirely abolished the inhibitory effect of these agonists on A4 and E2 secretion and resulted in an increase in T release. The addition of delta receptor agonists was followed by a decrease in basal A4, T and E2 secretion. The cells incubated in the presence of LH increased the androgen production and abrogated the inhibitory effect of delta agonists on E2 output. Basal A4, T and E2 release was also suppressed by kappa receptor agonists. The presence of LH in culture media extended the inhibitory effect of these opioids on E2 output and caused either abolition of the inhibitory influence of kappa agonists or even augmentation of both androgen release in response to the opioids. In conclusion, these data support the involvement of three major types of opioid receptors in the regulation of porcine granulosa cell steroidogenesis.     

The Influence of Ovarian Stromal/Theca Cells During In Vitro Culture on Steroidogenesis,Proliferation and Apoptosis of Granulosa Cells Derived from the Goat Ovary

Early follicular development is closely related to oocyte‐granulosa cells‐ovarian stromal cells/theca cells. The aim of the present study was to investigate the effects of ovarian cortical, medullary stromal and theca cells on oestradiol and progesterone biosynthesis, proliferation and apoptosis of goat ovary granulosa cells in vitro. Using Transwell coculture system, we evaluated steroidogenesis, cell proliferation and apoptosis, and some molecular expressions regarding steroidogenic enzyme, luteinizing hormone receptor and apoptosis‐related genes in granulosa cells. The results indicated that ovarian stromal/theca cells were able to stimulate oestradiol and progesterone production, promote cell proliferation and inhibit apoptosis of granulosa cells. Among all the three kinds of cells, theca cells affected strongly on granulosa cell function, and ovarian medullary stromal cells had the weakest effect on granulosa cells. These findings would provide an important knowledge of cell interaction among follicular cells during follicular development.     

Factors Modulating Apoptosis: an in-vitro Study in Swine Granulosa Cells

The aim of this study was to investigate the effects of some endocrine and intra‐ovarian factors on the activation/inhibition of apoptosis in swine granulosa cells. Upon incubation in a 10% FCS‐supplemented M199, granulosa cells from small (< 3 mm) follicles programmed their death after 24–48 h of culture; in the absence of FCS, apoptosis was reduced after 24 h of culture. Cells cultured in the presence of FCS were treated with db‐cAMP, LH, FSH, Insulin‐like Growth Factor‐I IGF‐I or PMSG to verify the role of these substances in apoptotic death: all these molecules inhibited apoptosis after 48 h of incubation. A further aim of the study was to investigate the possible involvement of nitric oxide (NO), an intra‐ovarian modulator, in the regulation of granulosa cell apoptosis and its possible role in the modulation of steroidogenesis. After a 48 h incubation with a substrate of NO synthesis ( l ‐arginine, 0.1 and 1 m m ), a NO donor [S‐nitroso‐N‐acetyl‐penicillamine (SNAP) , 0.2 and 1 m m ] or a NO synthase inhibitor [N^ω‐nitro‐ l ‐arginine‐methyl‐ester (NAME, 1 and 5 m m )], the onset of apoptotic death was evaluated: l . arginine and NAME did not induce any significant variation of apoptosis, whereas 1 m m SNAP exerted a protective action. A significant stimulatory effect of l ‐arginine on NO production, associated with a suppressive action on estradiol 17β concentrations was observed; NAME exerted an inhibitory effect on NO production, associated with an increase in estradiol secretion; estradiol 17β production was markedly inhibited by SNAP. In summary, the depletion of FCS could induce a cell cycle arrest in G₀ whereas apoptosis could be the consequence of cell cycle progression mediated by FCS; gonadotropins and IGF‐I could also act as survival factors. NO appeared to represent a ‘trophic’ signal for the follicle, whose involvement in the regulation of ovarian function is substantiated by its modulatory action on steroidogenesis.     

Low Molecular Mass Factors from Follicular Fluid Inhibit Steroidogenesis in Bovine Granulosa Cells

Gonadotropins are required for follicular growth and differentiation, but increasing amounts of evidence indicate that intrafollicular factors modulate their effects at granulosa cell level. In order to study the effect of factors present in bovine follicular fluid, a partial purification of low molecular mass factors from fluids collected from small (< 5 mm), medium (5–8 mm) and large (> 8 mm) follicles was performed and the biological activity of these peptides on steroidogenesis of granulosa cells from small and large follicles was examined. The purification was carried out by filtration through membranes in 25 and 10 kDa molecular weight cutoffs. After filtration, samples were analysed by polyacrylamide gel electrophoresis and protein concentration was measured by spectrophotometric analysis. Granulosa cells from small and large follicles were cultured in serum‐free DMEM/Ham's F12 (1 : 1) plus transferrin (5 mg/l) and selenium (5 µg/l) for 2 days. At the end of the culture period, media were renewed and follicular extracts from two different preparations (< 25 and < 10 kDa) were added at the concentrations of 1–10–100–1000 ng/ml. After 24 h the media were collected and stored until estradiol 17β (E2) and progesterone (P4) determination by validated radio‐immuno‐assays. Basal P4 production was 18.3 ± 1.4 (mean ± SEM)and 9.8 ± 1.8 ng/24 h per 3 × 10⁴ cells from small and large follicles, respectively. Both < 10 and < 25 kDa extracts reduced P4 production by cells from both the types of follicles (p < 0.05). Basal E2 release was 671.8 ± 21.4 and 5500 ± 800 pg/24 h per 3 × 10⁴ cells from small and large follicles, respectively. Both extracts reduced E2 production by either cells from small and large follicles (p < 0.05). No differences were observed in the inhibition of steroidogenesis by purifications obtained from large, medium or small follicles. Results of this study indicate that factors present in bovine follicular fluid can reduce steroidogenesis in granulosa cells in vitro.     

OPN5对鸭颗粒细胞凋亡、增殖及类固醇激素生成的影响

旨在研究视神经蛋白（neuropsin,OPN5）对鸭颗粒细胞凋亡、增殖及类固醇激素生成的影响。本研究分别对鸭颗粒细胞进行OPN5过表达质粒和OPN5 siRNA处理72 h （n=6）,应用EdU细胞增殖检测技术、流式细胞技术、Annexin V-FITC、RT-PCR、Western blot及ELISA技术系统地检测颗粒细胞的增殖、凋亡情况及生殖相关基因的mRNA、蛋白水平及激素水平的变化规律。结果显示,OPN5过表达能促进鸭卵泡颗粒细胞增殖,抑制鸭卵泡颗粒细胞凋亡;能极显著地促进GnRHR、FSHR、LHR的表达 ,并抑制GnIH、GnIHR的表达（P<0.01）;能显著或极显著上调StAR、CYP11A1、3β-HSD、CYP17A1、CYP19A1的mRNA水平（P<0.05或P<0.01）;显著升高OPN5、3β-HSD及CYP19A1的蛋白表达水平（P<0.05）和极显著升高E2、P4分泌水平（P<0.01）,并极显著降低INHβ的水平（P<0.01）。OPN5 siRNA能够显著降低OPN5的表达水平（P<0.01）,抑制卵泡颗粒细胞增殖并促进凋亡,极显著下调GnRH、GnRHR、FSHR、LHR（P<0.01）,促进GnIH、GnIHR的表达（P<0.01）;并极显著抑制StAR、CYP11A1、CYP17A1的表达（P<0.01）;显著降低OPN5、3β-HSD及CYP19A1蛋白表达水平（P<0.05）及极显著降低E2、P4的分泌水平（P<0.01）,并能极显著升高INHβ的水平（P<0.01）。研究表明,OPN5能促进鸭卵泡颗粒细胞的增殖,抑制其凋亡,促进颗粒细胞中类固醇激素的生成和分泌。     

SMAD7对山羊卵泡颗粒细胞增殖、凋亡的影响

旨在探究SMAD7对山羊卵泡颗粒细胞增殖和凋亡的影响。本试验收集3~4月龄大足黑山羊母羊的卵泡颗粒细胞,通过过表达或siRNA干扰、ELISA、qRT-PCR、Western blot及流式细胞术等技术与方法探究SMAD7对颗粒细胞增殖、凋亡及类固醇激素分泌的影响。结果发现,SMAD7过表达显著下调颗粒细胞增殖活力并促进细胞凋亡,抑制PCNA表达（P<0.05）,下调BCL2/BAX的比值（P<0.01）;同时,SMAD7干扰显著上调颗粒细胞增殖活力,显著上调PCNA表达（P<0.05）与BCL2/BAX表达量比值（P<0.05）。SMAD7过表达极显著上调颗粒细胞的孕酮分泌,下调雌二醇表达水平（P<0.01）;同时SMAD7干扰极显著下调孕酮分泌,上调雌二醇分泌（P<0.01）。进一步研究发现,SMAD7过表达显著抑制SMAD2、SMAD3的mRNA和蛋白表达（P<0.05）;SMAD7干扰则显著促进SMAD2、SMAD3的mRNA和蛋白表达（P<0.05）。结果表明,SMAD7抑制山羊卵泡颗粒细胞的增殖和雌二醇分泌,促进凋亡和孕酮的合成,并且抑制SMAD2、SMAD3的表达,进而调节卵泡的发育与闭锁。     

神经生长因子对小鼠卵巢颗粒细胞增殖的影响

本研究旨在探索神经生长因子(nerve growth factor,NGF)对小鼠卵巢颗粒细胞增殖的影响。试验建立了小鼠卵巢颗粒细胞的原代培养体系,并通过免疫荧光技术对颗粒细胞进行鉴定和检测NGF及其受体在卵巢颗粒细胞上的表达,采用MTS法检测不同浓度的NGF对昆明小鼠卵巢颗粒细胞增殖的影响。卵巢颗粒细胞在10、50、100、500 ng/mL NGF作用24 h,用酶标仪测定细胞D_{490 nm}值,试验组与对照组相比均有促进增殖的影响（P<0.05）,50 ng/mL NGF试验组与对照组相比差异极显著（P<0.01）。结果表明,NGF在昆明小鼠的卵巢颗粒细胞中有表达,在一定浓度范围NGF可以促进卵巢颗粒细胞的增殖。     

Effect of Vitamin E on Bovine Granulosa Cells Apoptosis and Proliferation through Cx43

The aim of this study was to determine the effect of vitamin E on Cx43,the mechanism and function of vitamin E on bovine granulosa cells apoptosis and proliferation.In this study,granulosa cells were isolated from bovine ovary and cultivated in vitro by adding different concentration of vitamin E (0,25,50,100,200 and 500 μmol/L) for 24 h.After cultured,apoptotic cells were detected by FCM,mRNA expression levels of BCL2/BAX、P53 and Cx43 genes were determined by Real-time PCR and cell proliferation was detected by CCK8.The results showed that compared to control group,100 μmol/L vitamin E could significantly inhibit the apoptosis of granulosa cells (P<0.05).Real-time PCR detection results showed that vitamin E significantly changed the mRNA expression levels of BCL2/BAX,P53,Cx43 genes (P<0.05).Vitamin E could significantly improve granulosa cells proliferation when granulosa cells were treated for 24 and 36 h (P<0.05).The results provided a theoretical basis on further analysis for studing the influence mechanism of vitamin E on oocytes development and maturity,and improvement of female animal reproduction by influencing granulosa cells proliferation and apoptosis.     

维生素E通过间隙连接蛋白Cx43对牛颗粒细胞凋亡及增殖的影响

本研究旨在研究维生素E对间隙连接蛋白Cx43的影响和其对牛颗粒细胞增殖与凋亡的作用及其机制。将从牛卵巢中分离获得颗粒细胞进行体外培养,用不同浓度的维生素E (0、25、50、100、200、500 μmol/L)处理细胞24 h。采用流式细胞术检测颗粒细胞的凋亡率、实时荧光定量PCR法检测凋亡标志基因BCL2/BAX、P53及Cx43 mRNA的表达变化、CCK8法检测颗粒细胞的增殖变化。结果表明:流式细胞术检测显示,与对照组相比,体外培养过程中添加100 μmol/L维生素E可显著抑制颗粒细胞凋亡(P<0.05),实时荧光定量PCR检测显示维生素E能引起BCL2/BAX、P53及Cx43基因表达显著变化(P<0.05),CCK8检测显示维生素E处理细胞24和36 h时可以显著促进颗粒细胞增殖(P<0.05)。此研究结果为深入解析维生素E通过影响颗粒细胞增殖、凋亡进而影响卵母细胞发育、成熟的机制及提高雌性动物繁殖能力提供了理论依据。     

牛卵泡颗粒细胞无血清培养的形态学观察

McCoy’s5a为基础培养液添加硒、转铁蛋白、雄烯二酮、谷氨酰胺 ,对牛卵巢上大 (直径 >8mm)、中 ( 4mm <直径 <8mm)、小 (直径 <4mm)非闭锁卵泡的颗粒细胞进行无血清培养。McCoy’s5a无血清培养中的颗粒细胞形态与分化特点类似于体内情况 ,说明颗粒细胞在该培养条件下 ,其功能可能更接近体内的生理状况     

牛卵泡颗粒细胞无血清培养的形态学观察

以McCoy＇s 5a为基础培养液添加硒、转铁蛋白、雄烯二酮、谷氨酰胺，对牛卵巢上大（直径＞8mm）、中（4mm＜直径＜8mm）、小（直径＜4mm）非闭销卵泡的颗粒细胞进行无血清培养。结果表明，McCoy＇s 5a无血清培养中的颗粒细胞形态与分化特点类似于体内情况，说明颗粒细胞在该培养条件下，其功能可能更接近体内的生理状况。     

不同浓度GnIH对鸭颗粒细胞周期和增殖的影响

为了研究不同浓度GnIH对鸭颗粒细胞周期、增殖及相关基因表达的影响.本研究分别用不同浓度GnIH(0、0.1、1、10和100 ng ? mL-1)处理体外培养的鸭颗粒细胞24 h(n=3),观察细胞的生长状态,通过流式细胞术和EdU方法检测细胞周期和细胞增殖,并用qRT-PCR方法检测增殖相关基因CDK6、Cycli...     

PPARγ对猪血管内皮细胞增殖、迁移及小管形成的影响

试验旨在研究过氧化物酶体增殖物激活受体γ（peroxisome proliferator-activated receptors γ,PPARγ）对猪血管内皮细胞增殖、迁移及小管形成的影响,并探讨PPARγ在猪体外血管生成中的作用。设置PPARγ激动剂组（5、10、15、20 μmol/L罗格列酮）、抑制剂组（5、10、15、20 μmol/L T0070907）及对照组,通过iCelligence细胞功能分析、划痕试验和Matrigel基质胶三维培养,构建猪体外血管生成的模型,模拟猪体内血管生成的环境,分别对猪血管内皮细胞的增殖、迁移、小管形成能力进行测定,同时根据NCBI已有的相关序列,应用Primer Premier 5.0软件设计PPARγ基因特异性引物,利用SYBR GreenⅠ实时荧光定量PCR检测PPARγ基因mRNA相对表达量,对PPARγ的体外作用效果进行验证。结果显示,5、10 μmol/L罗格列酮能促进猪血管内皮细胞增殖、迁移及小管形成,T0070907的抑制效果在试验浓度区间内（5~15 μmol/L）随浓度升高而加强,较高浓度（20 μmol/L）的两种药物均由于药物毒性的影响对细胞活动产生干扰。此外,5~20 μmol/L罗格列酮和5~20 μmol/L T0070907能分别提高和降低PPARγ基因mRNA相对表达量,且浓度趋势与增殖、迁移、小管形成的试验结果一致。综上所述,通过激活PPARγ可以对猪血管内皮细胞的增殖、迁移及小管形成产生促进效果,提示其在猪体外血管生成中具有积极作用,可为研究PPARγ对猪胎盘血管发生的影响提供参考依据。     

Bcl-2基因RNA干扰对体外培养的鹅卵泡颗粒细胞凋亡、增殖和孕激素分泌的影响

根据已发表的Bcl-2基因序列设计3对siRNA（Small interference RNA）序列，构建干扰表达载体，转染体外培养的鹅卵泡颗粒细胞，48h后利用流式细胞术（Flow cytometry，FCM）检测颗粒细胞Bcl-2蛋白表达量、凋亡和增殖情况，收集细胞培养液用放射免疫分析法检测孕激素（P）的分泌水平；此外，还检测了F1～F4卵泡、最小的排卵前卵泡（The smallest preovulatory follicle，SPF）、小黄卵泡（Small yellow follicle，SYF）和闭锁卵泡（Atresic follicle）颗粒细胞Bcl-2蛋白表达和凋亡情况。结果表明：（1）各级卵泡颗粒细胞Bcl-2蛋白的表达存在着差异，正常卵泡颗粒细胞Bcl-2蛋白表达量显著高于闭锁卵泡（P〈0．05），SPF颗粒细胞Bcl-2蛋白表达水平显著高于SYF（P〈0．05）；（2）干扰组Bcl-2蛋白表达水平显著低于所有对照组（P〈0．05），而细胞凋亡指数（Apoptosis index，AI）、增殖指数（Proliferation index，PI）和P分泌水平均高于对照组。     

维生素E对蛋种鸡卵巢等级前颗粒细胞增殖的影响

通过对蛋种鸡颗粒细胞进行原代培养,研究维生素E(VE)对颗粒细胞增殖的影响.取海兰褐蛋种鸡颗粒细胞,培养7d,观察细胞的生长趋势,确定VE干预方案.细胞培养24 h后,开始VF的干预,试验分为6组,每组分别以含VE 0、10、50、150、200和250 mg/L培养液培养,每组3个重复,连续培养24、48、72 h后,用MTT法进行细胞增殖检测.结果显示:颗粒细胞体外培养的适应期为1d,3d细胞数量达到高峰,之后细胞进入停滞衰退期.VE干预后48 h内,各组细胞增殖率随VE浓度的增加而升高,72 h时,与对照组相比,10 mg/L组细胞增值率基本不变,其他各组随着剂量的升高有降低趋势.结果表明,维生素E能够促进体外培养颗粒细胞增殖,降低细胞凋亡率.     

水牛卵巢颗粒细胞的分离培养及凋亡测定

研究主要是通过比较水牛卵巢颗粒细胞在不同培养基中的生长状态,并对细胞的增殖、核型及凋亡情况进行检测,以了解水牛卵巢颗粒细胞体外生长特性,建立水牛卵巢颗粒细胞的体外培养体系。结果发现,分离获得的水牛卵巢颗粒细胞存活率约为60%;采用DMEM培养基,颗粒细胞的生长速度和生长状态优于TCM-199和DMEM/F12培养基;细胞培养24 h后开始零星增殖,3~5 d增殖速度达到高峰;第1、3、5、7代颗粒细胞正常核型比率差异不显著,均在85%以上;第1代颗粒细胞的凋亡率与第5代差异显著(P<0.05),与第7代差异极显著(P<0.01)。结果表明,DMEM培养基更适宜用于水牛颗粒细胞的体外培养;水牛颗粒细胞能稳定地进行传代培养,染色体的数目不会发生明显改变,但细胞凋亡率会随着培养代数的增加而明显升高。     

广东惠州生猪养殖现状调查及分析

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