首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 78 毫秒
1.
The aim of this study was to document the expression and localization of VEGF system comprising of VEGF isoforms (VEGF 120, VEGF 164 and VEGF 188) and their receptors (VEGFR1 and VEGFR2) in buffalo corpus luteum (CL) obtained from different stages of the oestrous cycle. Real‐time RT‐PCR (qPCR), Western blot and immunohistochemistry were applied to investigate mRNA expression, protein expression and localization of examined factors. In general, all the components of VEGF system (the VEGF isoforms and their receptors) were found in the water buffalo CL during the oestrous cycle. The mRNA as well as protein expression of VEGF system was highest during the early and mid‐luteal phase, which later steadily decreased (p < 0.05) after day 10 to reach the lowest level in regressed CL. As demonstrated by immunohistochemistry, VEGF protein was localized predominantly in luteal cells; however, VEGFR1 and VEGFR2 were localized in luteal cells as well as in endothelial cells. In conclusion, the dynamics of expression and localization of VEGF system in buffalo corpora lutea during the luteal phase were demonstrated in this study, indicating the possible role of VEGF system in the regulation of luteal angiogenesis and proliferation of luteal as well as endothelial cells through their non‐angiogenic function.  相似文献   

2.
Water buffaloes are easily adaptable animals, whose raising and economical exploitation have been growing in the last three decades all over the world. Hyperstimulation of ovarian function in this species is a common technique aiming to improve reproductive performance. Superovulatory treatment affects corpus luteum (CL) function, which is highly correlated to angiogenic process. The aim of this study was therefore to assess the temporal protein and mRNA expression of VEGF and its receptors in the CL of non-treated and superovulated buffaloes. For that purpose blood samples and CL from 36 healthy (30 untreated, groups 1–5, and 6 superovulated, group 6) non-pregnant buffaloes were collected and the samples were divided into 6 groups according to the age of CL. Plasma samples were submitted to RIA to measure progesterone concentration and CL were subjected to immunohistochemistry and real time PCR for VEGF (vascular endothelial growth factor), Flt-1 (fms-like tyrosine kinase receptor 1) and KDR (kinase insert domain containing region). The VEGF system protein and mRNA expression during CL life span of untreated animals showed a specific time-dependent profile, although protein did not always reflect mRNA concentrations. VEGF expression in luteal cells was high correlated to plasma progesterone levels. Superovulated CL showed a significant increase of the VEGF-system protein and a significant decrease of mRNA expression compared to untreated animals in the same stage of the oestrous cycle. We conclude that VEGF, Flt-1 and KDR protein and mRNA expression in buffalo CL is dependent of estrous cycle stage and superovulatory treatment is able to increase the translation rate of this system.  相似文献   

3.
The objective of this study was to document the expression and localization of angiopoietin (ANGPT) family members comprising of angiopoietin (ANGPT1 and ANGPT2), and their receptors (Tie1 and Tie2) in buffalo corpus luteum (CL) obtained from different stages of the oestrous cycle, and the modulatory role of ANGPT1 and ANGPT2 alone or in combinations on progesterone (P4) secretion and mRNA expression of phosphotidylinositide‐3kinase‐protein kinase B (PI3K‐AKT), phosphoinositide‐dependent kinase (PDK), protein kinase B (AKT), Bcl2 associated death promoter (BAD), caspase 3 and von willebrand factor (vWF) in luteal cells obtained from midluteal phase (MLP) of oestrous cycle in buffalo. Real‐time RT‐PCR (qPCR), Western blot and immunohistochemistry were applied to investigate mRNA expression, protein expression and localization of examined factors whereas, the P4 secretion was assessed by RIA. The mRNA and protein expression of ANGPT1 and Tie2 was maximum (p < .05) in mid luteal phase (MLP) of oestrous cycle. The ANGPT2 mRNA and protein expression was maximum (p < .05) in early luteal phase, decreased in MLP and again increased in late luteal phase of oestrous cycle. ANGPT family members were localized in luteal cells and endothelial cells with a stage specific immunoreactivity. P4 secretion was highest (p < .05) with 100 ng/ml at 72 hr when luteal cells were treated with either protein alone. The mRNA expression of PDK, AKT and vWF was highest (p < .05) and BAD along with caspase 3 were lowest (p < .05) at 100 ng/ml at 72 hr of incubation period, when cultured luteal cells were treated with either protein alone or in combination. To conclude, our study explores the steroidogenic potential of angiopoietins to promote P4 secretion, luteal cell survival and angiogenesis through an autocrine and paracrine actions in buffalo CL.  相似文献   

4.
  相似文献   

5.
  相似文献   

6.
  相似文献   

7.
Adiponectin is an adipocyte‐derived hormone regulating energy metabolism, insulin sensitivity and recently found to regulate reproduction. The current study was carried out to investigate gene and protein expression, immunolocalization of adiponectin and its receptors AdipoR1 and AdipoR2 in ovarian follicles of different developmental stages in water buffalo (Bubalus bubalis) and to investigate the effect of adiponectin on steroid production in cultured bubaline granulosa cells. qPCR, western blotting and immunohistochemistry were applied to demonstrate mRNA expression, protein expression and immunolocalization, respectively. The results indicate that adiponectin, AdipoR1 and AdipoR2 were present in granulosa cells (GC) and theca interna (TI) of ovarian follicles and the expression of adiponectin, AdipoR1, AdipoR2 in GC and AdipoR1 and AdipoR2 in TI increased with increase in follicle size (p < .05). Expression of adiponectin was high in small and medium size follicles in TI. The adiponectin and its receptors were immunolocalized in the cytoplasm of GC and TI cells. Further, in the in‐vitro study, GCs were cultured and treated with recombinant adiponectin each at 0, 1 and 10 µg/ml alone or with follicle stimulating hormone (FSH) at 30 ng/ml) or Insulin‐like growth factor I (IGF‐I) at 10 ng/ml for 48 hr after obtaining 75%–80%s confluency. Adiponectin at 10 µg/ml increased IGF‐I‐induced estradiol (E2) and progesterone (P4) secretion and FSH‐induced E2 secretion from GC and also increased the abundance of factors involved in E2 and P4 production (cytochrome P45019A1 [CYP19A1] and 3‐beta‐hydroxysteroid dehydrogenase [3β‐HSD]). In conclusion, this study provides novel evidence for the presence of adiponectin and its receptors in ovarian follicles and modulatory role of adiponectin on steroid production in buffalo.  相似文献   

8.
In the ovary, the development of new capillaries from pre‐existing ones (angiogenesis) is a complex event regulated by numerous local factors. The dominant regulators of angiogenesis in ovarian follicles and corpora lutea are the vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), insulin‐like growth factor (IGF), angiopoietin (ANPT) and hypoxia‐inducible factor (HIF) family members. Antral follicles in our study were classified according to the oestradiol‐17‐beta (E2) content in follicular fluid (FF) and were divided into five classes (E2 < 0.5, 0.5–5, 5–20, 20–180 and >180 ng/ml FF). The corresponding sizes of follicles were 5–7, 8–10, 10–13, 12–14 and >14 mm, respectively. Follicle tissue was separated in theca interna (TI) and granulosa cells (GC). The corpora lutea (CL) in our study were assigned to the following stages: days 1–2, 3–4, 5–7, 8–12 13–16 and >18 of the oestrous cycle and months 1–2, 3–4, 6–7 and >8 of pregnancy. The dominant regulators were measured at mRNA and protein expression levels; mRNA was quantified by RT‐qPCR, hormone concentrations by RIA or EIA and their localization by immunohistochemistry. The highest expression for VEGF‐A, FGF‐2, IGF‐1 and IGF‐2, ANPT‐2/ANPT‐1 and HIF‐1‐alpha was found during final follicle maturation and in CL during the early luteal phase (days 1–4) followed by a lower plateau afterwards. The results suggest the importance of these factors for angiogenesis and maintenance of capillary structures for final follicle maturation, CL development and function.  相似文献   

9.
The aim of the study and short review was to present evidence that growth hormone (GH), locally produced insulin-like growth factors (IGFs), and IGF-binding proteins (IGFBPs) may have an important role in the control of ovarian function. There is clear evidence for a distinct GH-receptor mRNA expression and protein production in follicles (oocytes and granulosa-cumulus cells) and corpus luteum (CL). In hypophysectomized ewes, GH and LH are necessary for normal CL development. IGF-1 mRNA in the follicles is expressed in theca interstitial cells (TIC) and granulosa cells (GC) with already higher levels in the TIC before follicle selection. In contrast, IGF-2 is mainly expressed in the TIC. The IGFR-1 mRNA is expressed in both the TIC and GC, with increasing levels in GC during the final development of dominant follicles. IGF-1 is a very potent stimulator of progesterone and oxytocin release in GC. IGFBP-1, -2, -3, -4, -5, and -6 have been isolated from follicular fluid or ovarian tissue. Studies indicate that IGFBP expression and production in the developing follicle is dependent on both cell type and follicle size and is regulated by IGF-1 and gonadotropins. The highest expression of IGF-1 and IGFR-1 mRNA was demonstrated during the early luteal phase. Distinct receptors for IGF-1 and IGF-2 were present in CL membrane preparations at all stages investigated. Intense immunostaining for IGF-1 was observed mainly in bovine large and small luteal cells and in a limited number of endothelial cells. In contrast, IGF-2 protein was localized in perivascular fibroblast and pericytes of the capillaries. With the use of a microdialysis system, we found that in vitro and in vivo IGF-1, IGF-2, and GH stimulated the release of progesterone in cultures of luteal cells or intact tissues. In conclusion, there is clear evidence for a central role of the IGFs, IGFBPs, and GH in follicular development and CL function.  相似文献   

10.
  相似文献   

11.
  相似文献   

12.
Follicle selection is associated with an increase in the expression of vascular endothelial growth factor (VEGF) and its receptors in granulosa cells, however, the roles of VEGF in regulating the function of these or other non-endothelial cells in the ovary have not been explored in detail. The current study used bovine cell cultures to investigate potential roles of VEGF in the regulation of granulosa cell function during follicle development. Granulosa cells were obtained from morphologically healthy follicles 4 to 8 mm or 9 to 14 mm in diameter (corresponding to diameters before and after the establishment of dominance, respectively, during a bovine follicular wave) and exposed to a range of VEGF concentrations (1 to 100 ng/mL) encompassing concentrations found naturally in bovine dominant follicles. A concentration of VEGF of 1 ng/mL induced significant proliferation of granulosa cells from 4- to 8-mm follicles (P = 0.024) and increased the proliferative response of these cells to follicle-stimulating hormone (FSH; P = 0.045); whereas higher doses of VEGF had no effect on proliferation (P = 0.9). Treatment with VEGF induced an overall increase in mean extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation (P = 0.02). In contrast, VEGF, alone or in combination with FSH, had no effect on expression of the steroidogenic enzyme, CYP11A1, by cells from 4- to 8-mm follicles (P = 0.9). Granulosa cells from 9- to 14-mm follicles responded to 1 ng/mL VEGF with an increase in expression of the ovulation-associated gene, PTGS2 (P = 0.003) but higher VEGF doses had no effect (P = 0.9). The PTGS2 response to 1 ng/mL VEGF was similar to that induced by treatment with luteinizing hormone (LH). Interestingly, the stimulatory effects of LH on ERK1/2 phosphorylation (P = 0.003) and PTGS2 expression (P < 0.01) in granulosa cells from 9- to 14-mm follicles were abolished (P = 0.2) by specific chemical inhibition of VEGF receptor 2 (VEGFR2). These results suggest novel and important roles of VEGF and its receptor, VEGFR2, in mediating and/or enhancing the effects of gonadotropins in granulosa cells.  相似文献   

13.
对24只关中奶山羊采用“促卵泡素+前列腺素+孕酮”激素组合进行超排。依据不同的放栓处理,将其分为2组,每组12只。组Ⅰ在放栓后第15天早去栓,组Ⅱ在首次放栓后的第8天早换新栓,并于第15天晚去栓。结果表明:两组间平均黄体数和平均采胚数差异均不显著(P>0.05);两组间平均大卵泡数差异显著(P<0.05)。组Ⅰ有3只山羊发生未成熟黄体退化现象,2只伴有大卵泡;组Ⅱ有2只山羊发生未成熟黄体退化现象,且伴有大卵泡。对正常黄体和未成熟退化黄体的结构分析发现,未成熟退化黄体的特点是各种类型细胞萎缩,细胞间存在大量胶原纤维;大黄体细胞占优势,而小黄体细胞、成纤维细胞和上皮细胞很少见。  相似文献   

14.
In order to investigate the expression pattern of C-type natriuretic peptide（CNP）and its receptors（NPR）in buffalo follicles,firstly,the mRNA expression level of ANP,BNP,CNP,NPR1 and NPR2 in ovary were assayed by Real-time quantitative PCR;Secondly,the protein expression of CNP and NPR2 in buffalo follicles were detected by immunohistochemical stainning method;Lastly,the mRNA expression level of CNP and NPR2 in granule cells and cumulus cells were assayed by Real-time quantitative PCR.The results showed that CNP gene and its receptor NPR2 mainly expressed in buffalo ovary,the protein of CNP and NPR2 expressed in all stages of follicles,CNP mainly expressed in mural granulosa cells and NPR2 primarily presented in cumulus cells,the mRNA expression of CNP gene in granule cells was significantly higher than cumulus cells（P<0.05),whereas the mRNA expression of NPR2 gene in cumulus cells was significantly higher than granule cells（P<0.05).In conclusion,among the main members of natriuretic peptides and its receptors,CNP and NPR2 presented strong expression in buffalo ovary.CNP mainly expressed in mural granulosa cells,but NPR2 primarily presented in cumulus cells which arounding oocytes.  相似文献   

15.
为了探明C型利钠肽（C-type natriuretic peptide,CNP）及其受体（natriuretic peptide receptor,NPR）在水牛卵泡中的表达模式,本研究首先采用实时荧光定量PCR技术检测水牛卵巢中利钠肽家族主要成员A型、B型、C型利钠肽（ANP、BNP、CNP）及其Ⅰ型、Ⅱ型受体（NPR1、NPR2）的mRNA表达情况,然后利用免疫组化技术对水牛卵泡中CNP及NPR2蛋白进行定位,最后利用实时荧光定量PCR技术检测颗粒细胞和卵丘细胞中CNP及NPR2的mRNA表达规律。结果显示,水牛卵巢主要表达CNP及NPR2,且在各级卵泡中均有表达,其中,CNP主要在壁层颗粒细胞中表达,NPR2主要在卵丘细胞中表达;颗粒细胞上CNP mRNA表达水平显著高于卵母细胞周围的卵丘细胞（P<0.05）,而卵丘细胞上NPR2 mRNA表达水平显著高于颗粒细胞（P<0.05）。综上所述,在利钠肽主要家族成员和受体中,CNP和NPR2在水牛卵巢中呈现强表达,CNP主要在壁层颗粒细胞中表达,而NPR2主要在卵母细胞周围的卵丘细胞中表达。  相似文献   

16.
Endothelin-1 (ET-1), a 21-amino acid peptide was initially identified as a potent vasoconstrictor, ET-1 plays an important role in the female reproductive cycle: its quick ascent during luteal regression, ability to inhibit steroidogenesis in vitro and in vivo, combined with the observation that the luteolytic effects of prostaglandin F2alpha (PGF2alpha) were delayed by pretreatment with ET-1 receptors type A (ETA) antagonists suggest that this peptide functions as an important element of the luteolytic cascade. The observation that ETA receptor expression was inversely correlated with steroidogenesis in luteal cells; namely factors which stimulated steroidogenesis inhibited ETA receptor levels is also in accord with the inhibitory role of ET-1 in corpus luteum (CL) function. Contrary to the mature mid cycle CL, the CL of early cycle is refractory to PGF2alpha-induced luteolysis. PGF2alpha administered at early luteal phase (day 4 of the cycle) failed to increase luteal ET-1 gene expression or its ETA receptors. In contrast, both genes were markedly induced in mid cycle CL exposed to PGF2alpha. ET-1 gene is transcribed as prepro ET-1 (ppET-1) and the active form of peptide is derived from the inactive intermediate big ET-1, by endothelin-converting enzyme-1 (ECE-1), therefore alterations in mature ET-1 levels can be achieved by modulating the expression of ppET-1 and/or ECE-1. Analysis using in situ hybridization and enriched luteal cell subpopulations showed that both steroidogenic and endothelial cells of the CL expressed high levels of ECE-1 mRNA. The ppET-1 mRNA, on the other hand, was only expressed by resident endothelial cells, suggesting that luteal parenchymal and endothelial cells cooperate in the biosynthesis of mature bioactive ET-1. A significant, four-fold elevation in ECE-1 expression (mRNA and protein levels) occurred during the transition of the CL from early to mid luteal phase. This increase was accompanied by a significant rise in ET-1 peptide. Surprisingly however, ppET-1 mRNA levels remained similar during early and mid luteal phase. Collectively, these studies demonstrate that: (a) the various components of ET-1 system (ET-1/ECE-1/ETA) are dynamically and independently regulated during bovine luteal life span. (b) The CL becomes PGF2alpha-responsive only when both ppET-1 and ECE-1 genes are expressed at a level which enable an uninterrupted ET-1 biosynthesis.  相似文献   

17.
Tumour necrosis factor-α (TNF-α) is a cytokine that plays multiple important roles in corpus luteum (CL). Immunolocalization of expression of TNF-α in CL of buffalo was studied in different stages of its development and regression. Corpus luteum of healthy buffaloes (24) was collected from local slaughterhouses and categorized into early (stage I, 1–5 days, n = 6), mid (stage II, 6–11 days, n = 6), late luteal (stage III, 12–16 days, n = 6) and regressing phase (stage IV, 17–20 days, n = 6). In earliest phase of cyclic CL, per cent immunoexpression of TNF-α was significantly (p < .05) lower as compared to all phases with its expression being restricted to few developing luteal cells, usually in neutrophils. A significantly (p < .05) higher number of neutrophils with TNF-α immunoexpression were observed as compared to mid-luteal phase that indicated its role in initiation of angiogenesis at this stage. TNF-α immunoexpression almost doubled in mid-luteal phase, but the number of neutrophils exhibiting TNF-α was significantly (p < .05) lower with respect to all phases of CL. Immunoexpression percentage in late luteal phase increased sharply being significantly (p < .05) higher than earlier two phases of CL. In regressing phase, per cent immunostaining was maximum with highly significant (p < .05) difference as compared to all other stages, observed in all degrading luteal cells, abundant immune cells, that is neutrophils and macrophages which finally led to apoptosis and phagocytosis. Immunoexpression of TNF-α in early luteal phases served its role in initiation of angiogenesis, and its intense expression in regressing phase of CL suggested a shift in its role to apoptosis and structural luteal regression signifying both luteotropic and luteolytic roles in buffalo. This is probably the first study of its kind in buffaloes.  相似文献   

18.
Improving our understanding of the mechanisms controlling the corpus luteum (CL) and its role in regulating the reproductive cycle should lead to improvements in the sustainability of today's global animal industry. The corpus luteum (CL) is a transient endocrine organ composed of a heterogeneous mixture steroidogenic, endothelial and immune cells, and it is becoming clear that immune mechanisms play a key role in CL regulation especially in luteolysis. Toll‐like receptors (TLR) mediate innate immune mechanisms via the production of pro‐inflammatory cytokines, especially within various tissues, although the role of TLR within CL remains unknown. Thus, the objectives of this study were to characterize TLR mRNA expression in the CL during the oestrous cycle and in pregnancy (day 30–50), and to examine the role of TLR signalling in luteal cells. Corpora lutea were collected at various stages of the cycle and pregnancy and analysed for TLR and cytokine mRNA expression. In addition, luteal cells were cultured with the TLR4 ligand (lipopolysaccharide, LPS) for 24 h to evaluate the role of TLR4 in regulating luteal function. Toll‐like receptors 1, 2, 4, 6, tumour necrosis factor alpha (TNF), interferon gamma (IFN‐G), and interleukin (IL)‐12, mRNA expressions were greatest in regressing CL compared with earlier stages (p < .05), whereas no change was observed for IL‐6 mRNA expression. Cytokine mRNA expression in cultured luteal cells was not altered by LPS. Based on these data, one or more of the TLRs found within the CL may play a role in luteolysis, perhaps via pro‐inflammatory cytokine mRNA expression.  相似文献   

19.
This study applied in vivo and in vitro methods to investigate the effect of dietary N-carbamoylglutamate (NCG) on lipid metabolism, inflammation and apoptosis related-gene expression in visceral adipose tissue and isolated adipocytes of Japanese seabass (Lateolabrax japonicus). A basal diet and a test diet supplemented with 720 mg/kg NCG were fed to the fish for 10 weeks. During the growth trial, no mortality and no significant differences in growth performance were observed in fish between the 2 groups (P > 0.05). Plasma Arg content and mRNA level of argininosuccinate synthetase (ASS) in adipose tissue were significantly increased, which indicated that NCG inclusion promoted endogenous Arg synthesis. Thereafter, the potential effects of NCG treatment on lipid metabolism-related genes expression were studied through in vivo and in vitro methods. In the present study, we successfully established a primary adipocytes culture system and isolated pre-adipocytes in vitro of Japanese seabass for the first time. Both the results in vivo and in vitro showed that NCG treatment decreased the mRNA levels of genes related to adipogenesis (fatty acid synthase, FASN), cholesterol synthesis (3-hydroxy-3-methylglutaryl-CoA reductase, HMGCR) and fat deposition (lipoprotein lipase [LPL] and leptin), which revealed the underlying mechanism of NCG on reducing fat deposition. The results of this study demonstrated that NCG inclusion reduced the expression of inflammatory and apoptosis cytokines markedly in vivo and in vitro. In conclusion, NCG did exert beneficial effects on ameliorating adipogenesis, inflammation and apoptosis via promoting Arg endogenous synthesis in Japanese seabass.  相似文献   

20.
The vascular endothelial growth factor (VEGF) is essential for follicular development by promoting follicular angiogenesis, as well as for the proliferation and survival of granulosa cells. The biological effects of VEGF are regulated by two membrane receptors, VEGFR1 and VEGFR2, and two soluble receptors, sVEGFR1 and sVEGFR2, which play an antagonistic role. Thus, the objective of this study was to identify the mRNA expression pattern of total VEGF, VEGFR1, VEGFR2, sVEGFR1 and sVEGFR2 in bovine preselected follicles (PRF) and post‐selected follicles (POF). The mRNA expression of these five genes in both granulosa cells (GC) and theca cells (TC) was compared between follicles classified as PRF and POF based on their diameter and on their ratio of estradiol/progesterone (E2/P4). Results showed a lower expression of mRNA of sVEGFR1 and sVEGFR2 in POF than in PRF (p < .05). Regarding the mRNA expression of total VEGF, VEGFR1 and VEGFR2, there was no difference between POF and PRF follicles (p > .05). Our results showed that the mRNA expression of VEGFR2 and sVEGFR1 was more abundant than the expression of VEGFR1 and sVEGFR2, while GC was the main source of mRNA for total VEGF. On the other hand, TC was the follicular compartment where the receptors were most expressed. Our results suggest that non‐dominant follicles maintain a greater concentration of the mRNA expression of both membrane and soluble VEGF receptors. On the other hand, follicular dominance is related to a reduction in the mRNA expression of sVEGFR1 and sVEGFR2, which may favour VEGF binding with VEGFR2 and, hence, improve the follicular health and development.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号