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Zhao M, Subudeng G, Zhao Y, Hao S, Li H. Effect of Cyclic Adenosine Monophosphate on Connexin 37 Expression in Sheep Cumulus-Oocyte Complexes. J Dev Biol 2024; 12:10. [PMID: 38651455 PMCID: PMC11036199 DOI: 10.3390/jdb12020010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/10/2024] [Accepted: 03/26/2024] [Indexed: 04/25/2024] Open
Abstract
Gap junctional connection (GJC) in the cumulus-oocyte complex (COC) provides necessary support for message communication and nutrient transmission required for mammalian oocyte maturation. Cyclic adenosine monophosphate (cAMP) is not only a prerequisite for regulating oocyte meiosis, but also the key intercellular factor for affecting GJC function in COCs. However, there are no reports on whether cAMP regulates connexin 37 (Cx37) expression, one of the main connexin proteins, in sheep COCs. In this study, the expression of Cx37 protein and gene in immature sheep COC was detected using immunohistochemistry and PCR. Subsequently, the effect of cAMP on Cx37 expression in sheep COCs cultured in a gonadotropin-free culture system for 10 min or 60 min was evaluated using competitive ELISA, real-time fluorescent quantitative PCR (RT-qPCR), and Western blot. The results showed that the Cx37 protein was present in sheep oocytes and cumulus cells; the same results were found with respect to GJA4 gene expression. In the gonadotropin-free culture system, compared to the control, significantly higher levels of cAMP as well as Cx37 gene and protein expression were found in sheep COCs following treatment in vitro with Forskolin and IBMX (100 μM and 500 μM)) for 10 min (p < 0.05). Compared to the controls (at 10 or 60 min), cAMP levels in sheep COCs were significantly elevated as a result of Forskolin and IBMX treatment (p < 0.05). Following culturing in vitro for 10 min or 60 min, Forskolin and IBMX treatment can significantly promote Cx37 expression in sheep COCs (p < 0.05), a phenomenon which can be counteracted when the culture media is supplemented with RP-cAMP, a cAMP-specific competitive inhibitor operating through suppression of the protein kinase A (PKA). In summary, this study reports the preliminary regulatory mechanism of cAMP involved in Cx37 expression for the first time, and provides a novel explanation for the interaction between cAMP and GJC communication during sheep COC culturing in vitro.
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Affiliation(s)
- Mengyao Zhao
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China; (M.Z.); (G.S.); (Y.Z.); (S.H.)
- Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot 010018, China
- Key Laboratory of Animal Embryo and Development Engineering of Autonomous Region Universities, Hohhot 010018, China
| | - Gerile Subudeng
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China; (M.Z.); (G.S.); (Y.Z.); (S.H.)
- Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Yufen Zhao
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China; (M.Z.); (G.S.); (Y.Z.); (S.H.)
- Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Shaoyu Hao
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China; (M.Z.); (G.S.); (Y.Z.); (S.H.)
- Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Haijun Li
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China; (M.Z.); (G.S.); (Y.Z.); (S.H.)
- Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot 010018, China
- Key Laboratory of Animal Embryo and Development Engineering of Autonomous Region Universities, Hohhot 010018, China
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Yin L, Wang W, Pang W, Yang G, Gao L, Chu G. Insulin regulates gap junction intercellular communication in porcine granulosa cells through modulation of connexin43 protein expression. Theriogenology 2023; 212:172-180. [PMID: 37738821 DOI: 10.1016/j.theriogenology.2023.09.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 09/11/2023] [Accepted: 09/13/2023] [Indexed: 09/24/2023]
Abstract
Gap junction intercellular communication (GJIC) among granulosa cells plays an important role in folliculogenesis, and it is temporal-spatially regulated during follicular development. Connexin (Cx) proteins predominantly form the basal structure of gap junctions in granulosa cells. In our study, immunohistochemical analysis revealed that Cx43 is the most widely expressed connexin in porcine follicles, especially among the large antral follicles. With application of insulin on porcine granulosa cells, we found that insulin significantly facilitated the protein level of Cx43, not mRNA level. This process is dependent on the phosphorylated activities of AKT and Erk since selective AKT and Erk inhibitors, LY294002 and U0126, respectively, hampered the potential of insulin to up-regulate Cx43 protein expression. As a consequence, the insulin-enhanced Cx43-couple GJIC activity in porcine granulosa cells was corresponding attenuated by the administration of LY294002 and U0126. Our findings provide a new insight into the molecular mechanisms by which insulin mediates cell-cell communication in porcine granulosa cells and sheds light on nutrition-reproduction interactions.
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Affiliation(s)
- Lin Yin
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Wusu Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Weijun Pang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Gongshe Yang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Lei Gao
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China.
| | - Guiyan Chu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China.
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De Los Reyes M, Palomino J, Villagra A, Ramirez G, Peralta OA, Parraguez VH, Aspee K. Effect of progesterone on in vitro meiotic maturation of canine oocytes associated with Cx37 and Cx43 gene expression. Theriogenology 2023; 204:50-57. [PMID: 37068395 DOI: 10.1016/j.theriogenology.2023.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 04/05/2023] [Accepted: 04/05/2023] [Indexed: 04/19/2023]
Abstract
Progesterone (P4) concentrations in canines are exceptionally high in the periovulatory period. However, the mechanisms by which P4 modulates final oocyte development in dogs remain to be characterized. The aim of this study was to evaluate the effect of P4 on meiotic development related to the gene expression of connexin 37 (Cx37) and connexin 43 (Cx43) in the canine cumlus oocyte complexes (COCs). COCs were isolated from 120 canine ovaries after a routine ovariohysterectomy. In each experiment, groups of COCs retrieved from the antral follicles were subjected to in vitro maturation (IVM) for 72 h without (control) or with P4 (50 μg/mL and 100 μg/mL) or the P4 receptor antagonist, aglepristone (RU534 at 1 μM and 10 μM). Some of the COCs recovered (from each group) after 72 h of IVM were subjected to meiotic evaluation; the remaining COCs, and those not subjected to IVM, were used to analyze the gene expression of Cx37 and Cx43 by qPCR. The results were evaluated using ANOVA. The addition of P4 increased (P < 0.05) the meiotic development compared to that in the control or aglepristone groups. The highest (P < 0.05) percentage of oocytes in the MII stage was observed upon P4 supplementation. In contrast, the highest percentage (P < 0.05) of oocytes arrested in the GV stage and the lowest (P < 0.05) percentages in the MII stage were observed for COCs cultured with aglepristone. Although a significant decrease in the mRNA levels of both connexins was observed after culturing, no effect on Cx37 and Cx43 gene expression was observed when exogenous P4 was added compared to those of the control group. However, COCs cultured with aglepristone exhibited higher (P < 0.05) expression of Cx37 and Cx43 than COCs in the control IVM-group, regardless of the concentration. In conclusion, our results suggest that a high dosage of P4 during IVM enhances the nuclear maturation of canine oocytes without altering the gene expression levels of Cx37 and Cx43. However, the increase in their expression upon treatment with a P4 antagonist indicates an in vivo role for this hormone in the endogenous modulation of both Cx37 and Cx43.
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Affiliation(s)
- Monica De Los Reyes
- Laboratory of Animal Reproduction, Faculty of Veterinary Sciences, University of Chile, Santiago, Chile.
| | - Jaime Palomino
- Laboratory of Animal Reproduction, Faculty of Veterinary Sciences, University of Chile, Santiago, Chile; College of Veterinary Medicine, Bernardo O'Higgins University, Santiago, Chile
| | - Allison Villagra
- Laboratory of Animal Reproduction, Faculty of Veterinary Sciences, University of Chile, Santiago, Chile
| | - George Ramirez
- Laboratory of Animal Reproduction, Faculty of Veterinary Sciences, University of Chile, Santiago, Chile
| | - Oscar A Peralta
- Laboratory of Animal Reproduction, Faculty of Veterinary Sciences, University of Chile, Santiago, Chile
| | - Victor H Parraguez
- Laboratory of Animal Physiology, Faculty of Veterinary Sciences, University of Chile, Santiago, Chile
| | - Karla Aspee
- Laboratory of Animal Reproduction, Faculty of Veterinary Sciences, University of Chile, Santiago, Chile
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Di Berardino C, Liverani L, Peserico A, Capacchietti G, Russo V, Bernabò N, Tosi U, Boccaccini AR, Barboni B. When Electrospun Fiber Support Matters: In Vitro Ovine Long-Term Folliculogenesis on Poly (Epsilon Caprolactone) (PCL)-Patterned Fibers. Cells 2022; 11:cells11121968. [PMID: 35741097 PMCID: PMC9222101 DOI: 10.3390/cells11121968] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 06/17/2022] [Indexed: 12/14/2022] Open
Abstract
Current assisted reproduction technologies (ART) are insufficient to cover the slice of the population needing to restore fertility, as well as to amplify the reproductive performance of domestic animals or endangered species. The design of dedicated reproductive scaffolds has opened the possibility to better recapitulate the reproductive 3D ovarian environment, thus potentially innovating in vitro folliculogenesis (ivF) techniques. To this aim, the present research has been designed to compare ovine preantral follicles in vitro culture on poly(epsilon-caprolactone) (PCL)-based electrospun scaffolds designed with different topology (Random vs. Patterned fibers) with a previously validated system. The ivF performances were assessed after 14 days under 3D-oil, Two-Step (7 days in 3D-oil and on scaffold), or One-Step PCL protocols (14 days on PCL-scaffold) by assessing morphological and functional outcomes. The results show that Two- and One-Step PCL ivF protocols, when performed on patterned scaffolds, were both able to support follicle growth, antrum formation, and the upregulation of follicle marker genes leading to a greater oocyte meiotic competence than in the 3D-oil system. In conclusion, the One-Step approach could be proposed as a practical and valid strategy to support a synergic follicle-oocyte in vitro development, providing an innovative tool to enhance the availability of matured gametes on an individual basis for ART purposes.
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Affiliation(s)
- Chiara Di Berardino
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, 64100 Teramo, Italy; (A.P.); (G.C.); (V.R.); (N.B.); (U.T.); (B.B.)
- Correspondence:
| | - Liliana Liverani
- Institute of Biomaterials, Department of Materials Science and Engineering, Friedrich-Alexander University of Erlangen-Nuremberg, 91054 Erlangen, Germany; (L.L.); (A.R.B.)
| | - Alessia Peserico
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, 64100 Teramo, Italy; (A.P.); (G.C.); (V.R.); (N.B.); (U.T.); (B.B.)
| | - Giulia Capacchietti
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, 64100 Teramo, Italy; (A.P.); (G.C.); (V.R.); (N.B.); (U.T.); (B.B.)
| | - Valentina Russo
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, 64100 Teramo, Italy; (A.P.); (G.C.); (V.R.); (N.B.); (U.T.); (B.B.)
| | - Nicola Bernabò
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, 64100 Teramo, Italy; (A.P.); (G.C.); (V.R.); (N.B.); (U.T.); (B.B.)
| | - Umberto Tosi
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, 64100 Teramo, Italy; (A.P.); (G.C.); (V.R.); (N.B.); (U.T.); (B.B.)
| | - Aldo Roberto Boccaccini
- Institute of Biomaterials, Department of Materials Science and Engineering, Friedrich-Alexander University of Erlangen-Nuremberg, 91054 Erlangen, Germany; (L.L.); (A.R.B.)
| | - Barbara Barboni
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, 64100 Teramo, Italy; (A.P.); (G.C.); (V.R.); (N.B.); (U.T.); (B.B.)
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Hao T, Xu X, Hao H, Du W, Pang Y, Zhao S, Zou H, Yang S, Zhu H, Yang Y, Zhao X. Melatonin improves the maturation and developmental ability of bovine oocytes by up-regulating GJA4 to enhance gap junction intercellular communication. Reprod Fertil Dev 2021; 33:760-771. [PMID: 34585659 DOI: 10.1071/rd21145] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 08/05/2021] [Indexed: 01/03/2023] Open
Abstract
Melatonin (MT) increases oocyte maturation by reducing reactive oxygen species level and enhancing oocyte antioxidant capacity. However, the mechanisms via which MT works are still poorly understood. In the present study, the effects of MT on the maturation rate and development ability of bovine oocytes were investigated. Then, the transcriptome of oocytes treated by MT was sequenced. Finally, the expression of gap junction protein alpha 4 (GJA4) protein and cAMP level were detected in bovine oocytes, and isoprenaline (enhancer of gap junctional intercellular communication (GJIC)) and heptanol (inhibitor of GJIC) were used to investigate the effect of MT on GJIC activity in bovine oocytes. Our results showed that MT significantly improved the maturation, developmental ability and mRNA expression of GJA4 of bovine oocytes. Meanwhile, MT significantly increased GJA4 protein level and cAMP level in bovine oocytes. In contrast to heptanol, both isoproterenol and MT significantly increased GJIC activity, nuclear maturation and the development ability of bovine oocytes. However, MT significantly restored the nuclear maturation and developmental ability of oocytes treated by heptanol. In conclusion, our results showed that MT improves the maturation and developmental ability of bovine oocytes by enhancing GJIC activity via up-regulating GJA4 protein expression in IVM progress.
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Affiliation(s)
- Tong Hao
- Embryo Biotechnology and Reproduction Laboratory, Institute of Animal Sciences (IAS), Chinese Academy of Agricultural Sciences (CAAS), No. 2 Yuanmingyuan Western Road, Haidian District, Beijing 100193, PR China
| | - Xi Xu
- Embryo Biotechnology and Reproduction Laboratory, Institute of Animal Sciences (IAS), Chinese Academy of Agricultural Sciences (CAAS), No. 2 Yuanmingyuan Western Road, Haidian District, Beijing 100193, PR China
| | - Haisheng Hao
- Embryo Biotechnology and Reproduction Laboratory, Institute of Animal Sciences (IAS), Chinese Academy of Agricultural Sciences (CAAS), No. 2 Yuanmingyuan Western Road, Haidian District, Beijing 100193, PR China
| | - Weihua Du
- Embryo Biotechnology and Reproduction Laboratory, Institute of Animal Sciences (IAS), Chinese Academy of Agricultural Sciences (CAAS), No. 2 Yuanmingyuan Western Road, Haidian District, Beijing 100193, PR China
| | - Yunwei Pang
- Embryo Biotechnology and Reproduction Laboratory, Institute of Animal Sciences (IAS), Chinese Academy of Agricultural Sciences (CAAS), No. 2 Yuanmingyuan Western Road, Haidian District, Beijing 100193, PR China
| | - Shanjiang Zhao
- Embryo Biotechnology and Reproduction Laboratory, Institute of Animal Sciences (IAS), Chinese Academy of Agricultural Sciences (CAAS), No. 2 Yuanmingyuan Western Road, Haidian District, Beijing 100193, PR China
| | - Huiying Zou
- Embryo Biotechnology and Reproduction Laboratory, Institute of Animal Sciences (IAS), Chinese Academy of Agricultural Sciences (CAAS), No. 2 Yuanmingyuan Western Road, Haidian District, Beijing 100193, PR China
| | - Sha Yang
- Embryo Biotechnology and Reproduction Laboratory, Institute of Animal Sciences (IAS), Chinese Academy of Agricultural Sciences (CAAS), No. 2 Yuanmingyuan Western Road, Haidian District, Beijing 100193, PR China
| | - Huabin Zhu
- Embryo Biotechnology and Reproduction Laboratory, Institute of Animal Sciences (IAS), Chinese Academy of Agricultural Sciences (CAAS), No. 2 Yuanmingyuan Western Road, Haidian District, Beijing 100193, PR China
| | - Yuze Yang
- Beijing General Station of Animal Husbandry, Beijing 100101, PR China
| | - Xueming Zhao
- Embryo Biotechnology and Reproduction Laboratory, Institute of Animal Sciences (IAS), Chinese Academy of Agricultural Sciences (CAAS), No. 2 Yuanmingyuan Western Road, Haidian District, Beijing 100193, PR China
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Namei E, Sun W, Pan D, Zhao Y, Yang B, Weng Y, Du C, Li H, Yu B, Subudeng G. The advanced paraffin-section preparation technique based on multiple cumulus-oocyte complexes rather than ovaries in ovine. Reprod Biol 2020; 21:100473. [PMID: 33373929 DOI: 10.1016/j.repbio.2020.100473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/09/2020] [Accepted: 12/12/2020] [Indexed: 11/17/2022]
Abstract
Immunohistochemical staining is the important method for the identification of protein expression in mammal ovaries, in particular in the follicles with the potential to develop into cumulus-oocyte complexes (COCs), which are able to support oocyte maturation regardless of in vivo or in vitro. Here, we reported an advanced immunohistochemical method based on an artificial structure gathering multiple COCs by paraffin embedding for rapid and highly sensitive detection of co-expressed proteins in ovine COCs rather than ovaries. Compared with the conventional immunohistochemistry on ovine ovaries, the advanced COC paraffin sectioning technique showed the better immunostaining effect and featured the higher generation rate for COCs, the distincter cumulus layers, and the more simplified procedures. These results indicate that the COC paraffin sectioning technique is highly effectively applied for identification of protein expression in ovine COC.
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Affiliation(s)
- Erge Namei
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, PR China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot, 010018, PR China
| | - Wei Sun
- College of Life Science, Inner Mongolia University, Hohhot, 010070, PR China
| | - Deng Pan
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, PR China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot, 010018, PR China
| | - Yufen Zhao
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, PR China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot, 010018, PR China
| | - Bingxue Yang
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, PR China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot, 010018, PR China
| | - Yu Weng
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, PR China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot, 010018, PR China
| | - Chenguang Du
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, PR China
| | - Haijun Li
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, PR China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot, 010018, PR China.
| | - Boyang Yu
- College of Basic Medical, Inner Mongolia Medical University, Hohhot, 010110, PR China.
| | - Gerile Subudeng
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, PR China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Inner Mongolia Agricultural University, Hohhot, 010018, PR China.
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Kordowitzki P, Kranc W, Bryl R, Kempisty B, Skowronska A, Skowronski MT. The Relevance of Aquaporins for the Physiology, Pathology, and Aging of the Female Reproductive System in Mammals. Cells 2020; 9:cells9122570. [PMID: 33271827 PMCID: PMC7760214 DOI: 10.3390/cells9122570] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/23/2020] [Accepted: 11/29/2020] [Indexed: 12/26/2022] Open
Abstract
Aquaporins constitute a group of water channel proteins located in numerous cell types. These are pore-forming transmembrane proteins, which mediate the specific passage of water molecules through membranes. It is well-known that water homeostasis plays a crucial role in different reproductive processes, e.g., oocyte transport, hormonal secretion, completion of successful fertilization, blastocyst formation, pregnancy, and birth. Further, aquaporins are involved in the process of spermatogenesis, and they have been reported to be involved during the storage of spermatozoa. It is noteworthy that aquaporins are relevant for the physiological function of specific parts in the female reproductive system, which will be presented in detail in the first section of this review. Moreover, they are relevant in different pathologies in the female reproductive system. The contribution of aquaporins in selected reproductive disorders and aging will be summarized in the second section of this review, followed by a section dedicated to aquaporin-related proteins. Since the relevance of aquaporins for the male reproductive system has been reviewed several times in the recent past, this review aims to provide an update on the distribution and impact of aquaporins only in the female reproductive system. Therefore, this paper seeks to determine the physiological and patho-physiological relevance of aquaporins on female reproduction, and female reproductive aging.
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Affiliation(s)
- Paweł Kordowitzki
- Department of Basic and Preclinical Sciences, Institute for Veterinary Medicine, Nicolaus Copernicus University, 87-100 Torun, Poland;
- Institute of Animal Reproduction and Food Research of Polish Academy of Sciences, 10-243 Olsztyn, Poland
| | - Wiesława Kranc
- Department of Anatomy, Poznan University of Medical Sciences, 60-781 Poznan, Poland; (W.K.); (R.B.); (B.K.)
| | - Rut Bryl
- Department of Anatomy, Poznan University of Medical Sciences, 60-781 Poznan, Poland; (W.K.); (R.B.); (B.K.)
| | - Bartosz Kempisty
- Department of Anatomy, Poznan University of Medical Sciences, 60-781 Poznan, Poland; (W.K.); (R.B.); (B.K.)
- Department of Histology and Embryology, Poznan University of Medical Sciences, 60-781 Poznan, Poland
- Department of Veterinary Surgery, Institute for Veterinary Medicine, Nicolaus Copernicus University, 87-100 Torun, Poland
| | - Agnieszka Skowronska
- Department of Human Physiology and Pathophysiology, School of Medicine, Collegium Medicum, University of Warmia and Mazury, Warszawska Street 30, 10-082 Olsztyn, Poland;
| | - Mariusz T. Skowronski
- Department of Basic and Preclinical Sciences, Institute for Veterinary Medicine, Nicolaus Copernicus University, 87-100 Torun, Poland;
- Correspondence: ; Tel.: +48-56-611-2231
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Bus A, Szymanska K, Pintelon I, Leroy JLMR, Leybaert L, Bols PEJ. Preservation of connexin 43 and transzonal projections in isolated bovine pre-antral follicles before and following vitrification. J Assist Reprod Genet 2020; 38:479-492. [PMID: 33159276 DOI: 10.1007/s10815-020-01993-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 10/26/2020] [Indexed: 02/07/2023] Open
Abstract
PURPOSE Gap junctions and transzonal projections play a crucial role in intercellular communication between different follicular components and are necessary for follicle development. We aimed to demonstrate gap junction protein connexin 43 (Cx43) and transzonal projections (TZPs) in viable, category 1, isolated bovine pre-antral follicles (PAFs) during short-term culture and after vitrification and warming. METHODS This study involved four experimental groups: fresh control, 2-day culture, 4-day culture, and vitrified secondary PAFs. Isolated PAFs were vitrified using a simple and efficient cryopreservation method by means of mini cell strainers. RESULTS Cx43 and TZPs were detected in pre-antral follicles of all stages, as well as in every experimental group. The group fresh follicles showed a higher percentage of follicles that were positive for Cx43 (91.7%) than the follicles that were vitrified (77.4%). All follicles that were cultured for 2 days were Cx43-positive (100%). Follicles cultured for 4 days (65.8%) (P = 0.002) showed the lowest percentage of follicles that were Cx43-positive. The percentages of the presence or (partial) absence of the TZP network were shown to be very heterogeneous between follicles in different treatment groups. CONCLUSIONS These results suggest the maintenance of communication between the oocyte and the somatic companion cells after vitrification and warming. The varying percentages of the expression of the TZP network within groups suggests that it will be of interest to investigate whether this is truly due to variability in TZP integrity and follicle quality or due to methodological limitations.
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Affiliation(s)
- Anniek Bus
- Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, Laboratory of Veterinary Physiology and Biochemistry, Gamete Research Centre, University of Antwerp, Universiteitsplein 1, U building, 2610, Wilrijk, Belgium.
| | - Katarzyna Szymanska
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, 310 Cedar Street, New Haven, CT, 06510, USA.,Faculty of Medicine and Health Sciences, Department of Basic and Applied Medical Sciences (BAMS), Physiology group, Ghent University, C. Heymanslaan 10, B-9000, Ghent, Belgium
| | - Isabel Pintelon
- Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, Laboratory of Cell Biology and Histology, University of Antwerp, Universiteitsplein 1, T building, 2610, Wilrijk, Belgium
| | - Jo L M R Leroy
- Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, Laboratory of Veterinary Physiology and Biochemistry, Gamete Research Centre, University of Antwerp, Universiteitsplein 1, U building, 2610, Wilrijk, Belgium
| | - Luc Leybaert
- Faculty of Medicine and Health Sciences, Department of Basic and Applied Medical Sciences (BAMS), Physiology group, Ghent University, C. Heymanslaan 10, B-9000, Ghent, Belgium
| | - Peter E J Bols
- Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, Laboratory of Veterinary Physiology and Biochemistry, Gamete Research Centre, University of Antwerp, Universiteitsplein 1, U building, 2610, Wilrijk, Belgium
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9
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De Los Reyes M, Palomino J, Gallegos C, Espinoza R, Dettleff P, Peralta OA, Parraguez VH, Ramirez G. Gene and protein expression of connexins 37 and 43 in cumulus-oocytes complexes throughout the canine oestrous cycle. Reprod Fertil Dev 2020; 32:976-987. [PMID: 32693910 DOI: 10.1071/rd20126] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 05/30/2020] [Indexed: 12/17/2022] Open
Abstract
The aim of this study was to evaluate the expression of connexin (Cx) 37 and Cx43 in canine cumulus-oocyte complexes (COCs) during the oestrous cycle. Cx localisation was analysed by immunohistochemistry and immunofluorescence, whereas protein and gene expression was evaluated by western blotting and quantitative polymerase chain reaction respectively; comparisons were made using analysis of variance. Both Cx37 and Cx43 were expressed in all follicular stages; Cx43 was identified in cumulus cells and Cx37 was identified in cumulus cells, zonae pellucida and oocytes. Immunofluorescence analyses showed that Cx37 remained unchanged during the preovulatory stage but decreased after ovulation, whereas Cx43 remained unchanged before and after ovulation. Cx43 transcripts increased (P<0.05) during anoestrus and dioestrus in medium-sized follicles but remained unaltered during the pro-oestrus and antral stages during oestrus, before and after ovulation. Cx37 mRNA levels decreased in ovulated COCs (P<0.05). The highest levels of Cx37 protein (P<0.05) were detected in the preantral stage during anoestrus. In contrast, strong Cx43 signals were detected in oestrus and in medium-sized antral follicles in dioestrus (P<0.05). Overall, we demonstrated that Cx37 and Cx43 exhibit different expression patterns, suggesting specific roles throughout growth. Maintenance of Cx expression before ovulation indicates the involvement of Cx37 and Cx43 in the prolonged meiotic arrest.
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Affiliation(s)
- Monica De Los Reyes
- Laboratory of Animal Reproduction, Department of Animal Production Faculty of Veterinary Sciences, University of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile; and Corresponding author.
| | - Jaime Palomino
- Laboratory of Animal Reproduction, Department of Animal Production Faculty of Veterinary Sciences, University of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile
| | - Carola Gallegos
- Laboratory of Animal Reproduction, Department of Animal Production Faculty of Veterinary Sciences, University of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile
| | - Roberto Espinoza
- Laboratory of Animal Reproduction, Department of Animal Production Faculty of Veterinary Sciences, University of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile
| | - Phillipe Dettleff
- Laboratory Inviogen, Department of Biological Sciences, Faculty of Veterinary Sciences, University of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile
| | - Oscar A Peralta
- Laboratory of Animal Reproduction, Department of Animal Production Faculty of Veterinary Sciences, University of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile
| | - Victor H Parraguez
- Laboratory of Animal Physiology, Department of Biological Sciences, Faculty of Veterinary Sciences, University of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile
| | - George Ramirez
- Laboratory of Animal Reproduction, Department of Animal Production Faculty of Veterinary Sciences, University of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile
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10
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Alam MH, Miyano T. Interaction between growing oocytes and granulosa cells in vitro. Reprod Med Biol 2020; 19:13-23. [PMID: 31956281 PMCID: PMC6955591 DOI: 10.1002/rmb2.12292] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 07/22/2019] [Accepted: 07/25/2019] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Oocyte growth is accompanied by follicular development in mammalian ovaries. Since the discovery of two oocyte-derived factors, growth differentiation factor 9 (GDF9), and bone morphogenetic protein 15 (BMP15), knowledge of the bidirectional communication between oocytes and granulosa cells for ovarian function and fertility has been accumulated. In addition, the growth culture system of oocytes has been improved, further promoting the studies on the communication between oocytes and granulosa cells in vitro. METHODS We provide an overview of the role of granulosa cells in oocyte growth and the role of oocytes in follicular development along with our recent findings in culture experiments of bovine growing oocytes. MAIN FINDINGS Granulosa cells supply nutrients and metabolites through gap junctions to oocytes and secrete paracrine signals to regulate oocytes. Oocytes regulate granulosa cell proliferation and differentiation and induce antrum formation via GDF9 and BMP15. CONCLUSION Oocytes actively participate in various aspects of follicular development, including antrum formation via the oocyte-derived factors GDF9 and BMP15, whose synthesis is probably regulated by granulosa cells. In vitro studies will reveal the precise communication loop between oocytes and granulosa cells that facilitates the coordinated development of oocytes and granulosa cells in the follicles.
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Affiliation(s)
- Md Hasanur Alam
- Department of Animal Science, Faculty of Animal HusbandryBangladesh Agricultural UniversityMymensinghBangladesh
- Graduate School of Agricultural ScienceKobe UniversityKobeJapan
| | - Takashi Miyano
- Graduate School of Agricultural ScienceKobe UniversityKobeJapan
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11
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Piersanti RL, Santos JEP, Sheldon IM, Bromfield JJ. Lipopolysaccharide and tumor necrosis factor-alpha alter gene expression of oocytes and cumulus cells during bovine in vitro maturation. Mol Reprod Dev 2019; 86:1909-1920. [PMID: 31663199 DOI: 10.1002/mrd.23288] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 10/08/2019] [Indexed: 12/23/2022]
Abstract
Communication between the oocyte and cumulus facilitates oocyte growth, cell cycle regulation, and metabolism. This communication is mediated by direct contact between oocytes and cumulus cells, and soluble secreted molecules. Secreted molecules involved in this process are known inflammatory mediators. Lipopolysaccharide (LPS) is detected in follicular fluid and is associated with reduced fertility, whereas accumulation of inflammatory mediators in follicular fluid, including tumor necrosis factor-α (TNF-α), is associated with female infertility. Maturation of oocytes in the presence of LPS or TNF-α reduces meiotic maturation and the capacity to develop to the blastocyst. Here we evaluated the abundance of 92 candidate genes involved immune function, epigenetic modifications, embryo development, oocyte secreted factors, apoptosis, cell cycle, and cell signaling in bovine cumulus cells or zona-free oocytes after exposure to LPS or TNF-α during in vitro maturation. We hypothesize that LPS or TNF-α will alter the abundance of transcripts in oocytes and cumulus cell in a cell type dependent manner. Exposure to LPS altered abundance of 31 transcripts in oocytes (including ACVR1V, BMP15, DNMT3A) and 12 transcripts in cumulus cells (including AREG, FGF4, PIK3IP1). Exposure to TNF-α altered 1 transcript in oocytes (IGF2) and 4 transcripts in cumulus cells (GJA1, PLD2, PTGER4, STAT1). Cumulus expansion was reduced after exposure to LPS or TNF-α. Exposing COCs to LPS had a marked effect on expression of targeted transcripts in oocytes. We propose that altered oocyte transcript abundance is associated with reduced meiotic maturation and embryo development observed in oocytes cultured in LPS or TNF-α.
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Affiliation(s)
- Rachel L Piersanti
- Department of Animal Sciences, University of Florida, Gainesville, Florida
| | - José E P Santos
- Department of Animal Sciences, University of Florida, Gainesville, Florida
| | - I Martin Sheldon
- Institute of Life Science, Swansea University Medical School, Swansea, United Kingdom
| | - John J Bromfield
- Department of Animal Sciences, University of Florida, Gainesville, Florida
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12
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Read CC, Dyce PW. All‐trans retinoic acid exposure increases connexin 43 expression in cumulus cells and improves embryo development in bovine oocytes. Mol Reprod Dev 2019; 86:1865-1873. [DOI: 10.1002/mrd.23274] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 09/06/2019] [Indexed: 12/16/2022]
Affiliation(s)
- Casey C. Read
- Department of Animal Sciences, College of AgricultureAuburn University Auburn Alabama
| | - Paul W. Dyce
- Department of Animal Sciences, College of AgricultureAuburn University Auburn Alabama
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13
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Is the pre-antral ovarian follicle the 'holy grail'for female fertility preservation? Anim Reprod Sci 2019; 207:119-130. [PMID: 31208845 DOI: 10.1016/j.anireprosci.2019.05.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 05/28/2019] [Accepted: 05/31/2019] [Indexed: 01/18/2023]
Abstract
Fertility preservation is not only a concern for humans with compromised fertility after cancer treatment. The preservation of genetic material from endangered animal species or animals with important genetic traits will also greatly benefit from the development of alternative fertility preservation strategies. In humans, embryo cryopreservation and mature-oocyte cryopreservation are currently the only approved methods for fertility preservation. Ovarian tissue cryopreservation is specifically indicated for prepubertal girls and women whose cancer treatment cannot be postponed. The cryopreservation of pre-antral follicles (PAFs) is a safer alternative for cancer patients who are at risk of the reintroduction of malignant cells. As PAFs account for the vast majority of follicles in the ovarian cortex, they represent an untapped potential, which could be cultivated for reproduction, preservation, or research purposes. Vitrification is being used more and more as it seems to yield better results compared to slow freezing, although protocols still need to be optimized for each specific cell type and species. Several methods can be used to assess follicle quality, ranging from simple viability stains to more complex xenografting procedures. In vitro development of PAFs to the pre-ovulatory stage has not yet been achieved in humans and larger animals. However, in vitro culture systems for PAFs are under development and are expected to become available in the near future. This review will focus on recent developments in (human) fertility preservation strategies, which are often accomplished by the use of in vitro animal models due to ethical considerations and the scarcity of human research material.
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14
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Michalovic L, Currin L, Gutierrez K, Bellefleur A, Glanzner WG, Schuermann Y, Macedo MP, Bohrer RC, Dicks N, Lopez R, Taibi M, Madogwe E, St‐Yves A, Mondadori RG, Gourdon J, Vigneault C, Baldassarre H, Bordignon V. Granulosa cells of prepubertal cattle respond to gonadotropin signaling and upregulate genes that promote follicular growth and prevent cell apoptosis. Mol Reprod Dev 2018; 85:909-920. [DOI: 10.1002/mrd.23066] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 10/05/2018] [Indexed: 01/20/2023]
Affiliation(s)
- Laura Michalovic
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Luke Currin
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Karina Gutierrez
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | | | - Werner G. Glanzner
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Yasmin Schuermann
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Mariana P. Macedo
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Rodrigo C. Bohrer
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Naomi Dicks
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Rosalba Lopez
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Milena Taibi
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Ejimedo Madogwe
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Audrey St‐Yves
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Rafael G. Mondadori
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Jim Gourdon
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
- Comparative Medicine and Animal Resources Centre, McGill UniversityMontreal Quebec Canada
| | | | - Hernan Baldassarre
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
| | - Vilceu Bordignon
- Department of Animal ScienceMcGill UniversitySainte‐Anne‐de‐Bellevue Quebec Canada
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15
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Snoeck F, Szymanska KJ, Sarrazin S, Ortiz-Escribano N, Leybaert L, Van Soom A. Blocking connexin channels during vitrification of immature cat oocytes improves maturation capacity after warming. Theriogenology 2018; 122:144-149. [PMID: 30268031 DOI: 10.1016/j.theriogenology.2018.09.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 09/05/2018] [Accepted: 09/12/2018] [Indexed: 11/28/2022]
Abstract
In the domestic cat, nuclear maturation and embryo development after vitrification of immature oocytes have been obtained but developmental competence after warming remains low. It has been reported that during folliculogenesis, the association and communication between the oocyte and the surrounding cumulus cells through connexin-based gap junctions is essential for normal oocyte and follicular development. Gap junctions result from the head-to-head interaction of two hemichannels; however, there is always a population of hemichannels not incorporated into gap junctions. These unopposed hemichannels are normally closed but may open under certain stress conditions, potentially also during vitrification and warming, turning them into toxic pores inducing cell injury and cell death. The aim of our study was to test whether inhibiting connexin 37 (Cx37) and connexin 43 (Cx43) channels with the connexin-targeting peptide Gap26 during vitrification and warming of cat immature cumulus-oocyte-complexes (COCs) could improve oocyte maturation and competence of resultant blastocysts derived by parthenogenetic activation. In the first experiment, our immunostainings confirmed the presence of Cx43 protein in the cytoplasm of immature cat oocytes and in the plasma membranes of cumulus cells. In the second experiment, COCs were randomly divided in three different groups: a control group (control), a group vitrified without Gap26 (vitrified) and a group vitrified with Gap26 (vitrified-peptide). The maturation rate was checked and oocytes from all three different experimental groups were parthenogenetically activated and cultured in vitro until day 8. After vitrification and warming, 49% of the oocytes in the control group matured, while this was 8% and 19% in the vitrified and vitrified-peptide groups, respectively. Compared to the vitrified group, oocytes in the vitrified-peptide group had significantly larger maturation rates. No blastocysts were detected at day 8 in the vitrified group, while 2% and 13% of the oocytes further developed to blastocyst at day 8 in the vitrified-peptide and control non-vitrified group, respectively. We conclude that the use of Gap26 in vitrification and warming media to vitrify immature cat oocytes improves maturation success and allows such oocytes to reach the blastocyst stage (2%) at day 8 after parthenogenetic activation.
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Affiliation(s)
- Féline Snoeck
- Faculty of Veterinary Medicine, Department of Reproduction, Obstetrics and Herd Health, Ghent University, Merelbeke, Belgium.
| | - Katarzyna Joanna Szymanska
- Faculty of Medicine and Health Sciences, Department of Basic Medical Sciences - Physiology Group, Ghent University, Ghent, Belgium
| | - Steven Sarrazin
- Faculty of Veterinary Medicine, Department of Reproduction, Obstetrics and Herd Health, Ghent University, Merelbeke, Belgium
| | - Nerea Ortiz-Escribano
- Faculty of Veterinary Medicine, Department of Reproduction, Obstetrics and Herd Health, Ghent University, Merelbeke, Belgium
| | - Luc Leybaert
- Faculty of Medicine and Health Sciences, Department of Basic Medical Sciences - Physiology Group, Ghent University, Ghent, Belgium
| | - Ann Van Soom
- Faculty of Veterinary Medicine, Department of Reproduction, Obstetrics and Herd Health, Ghent University, Merelbeke, Belgium
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16
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Del Collado M, Andrade GM, Meirelles FV, da Silveira JC, Perecin F. Contributions from the ovarian follicular environment to oocyte function. Anim Reprod 2018; 15:261-270. [PMID: 34178149 PMCID: PMC8202235 DOI: 10.21451/1984-3143-ar2018-0082] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The magnitude of oocyte's role for embryo development is categorical. This unique cell contains the machineries and cellular components necessary to remodel male and female chromatin, to sustain early development and to, ultimately, generate a complete and complex individual. However, to gain these competences before fertilization, the oocyte undergoes several morphological, cellular and molecular changes during its lifetime enclosed in the ovarian follicle. This review will briefly revisit how the oocyte orchestrate the follicular cells, and how molecules transit to the oocyte from the innermost (cumulus) and outermost (antrum and granulosa cells) layers surrounding the follicle-enclosed oocyte. Finally, we will discuss the interferences of in vitro culture conditions in the communication of the oocyte with its surrounding cells and the potential strategies to modulate these communication systems to increase oocyte competence.
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Affiliation(s)
- Maite Del Collado
- Faculty of Animal Sciences and Food Engineering, Department of Veterinary Medicine, University of São Paulo, Pirassununga, SP, Brazil
| | - Gabriella Mamede Andrade
- Faculty of Animal Sciences and Food Engineering, Department of Veterinary Medicine, University of São Paulo, Pirassununga, SP, Brazil
| | - Flávio Vieira Meirelles
- Faculty of Animal Sciences and Food Engineering, Department of Veterinary Medicine, University of São Paulo, Pirassununga, SP, Brazil
| | - Juliano Coelho da Silveira
- Faculty of Animal Sciences and Food Engineering, Department of Veterinary Medicine, University of São Paulo, Pirassununga, SP, Brazil
| | - Felipe Perecin
- Faculty of Animal Sciences and Food Engineering, Department of Veterinary Medicine, University of São Paulo, Pirassununga, SP, Brazil
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17
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Donfack NJ, Alves KA, Alves BG, Rocha RMP, Bruno JB, Bertolini M, Dos Santos RR, Domingues SFS, De Figueiredo JR, Smitz J, Rodrigues APR. Stroma cell-derived factor 1 and connexins (37 and 43) are preserved after vitrification and in vitro culture of goat ovarian cortex. Theriogenology 2018; 116:83-88. [PMID: 29783047 DOI: 10.1016/j.theriogenology.2018.05.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 05/02/2018] [Accepted: 05/03/2018] [Indexed: 12/13/2022]
Abstract
This study aimed to evaluate the follicular morphology and development (follicular activation, cell proliferation, and hormone production), as well as the distribution pattern of Connexins 37 and 43 and SDF-1α after vitrification and in vitro culture of goat ovarian tissue. The study involved four experimental groups: fresh control, vitrified control, fresh culture and vitrified culture. The ovarian fragments were vitrified by a solid surface technique using the Ovarian Tissue Cryosystem and subsequently in vitro cultured for 7 days. The percentage of normal preantral follicles was similar between vitrified control and vitrified culture. However, both vitrified control and vitrified culture treatments showed a significant reduction of morphologically normal follicles in comparison to fresh control. A higher percentage of developing follicles (transition, primary and secondary) was observed in both fresh culture and vitrified culture treatments. Progesterone and estradiol production decreased (P < 0.05) during in vitro culture. SDF-1α and Cx37 proteins were detected in oocytes and granulosa cells from all the treatments. However, in vitrified cultured tissue, only granulosa cells were labeled with Cx37. Connexin 43 was detected in the granulosa, theca cells and zona pellucida in all the treatments. In conclusion, in vitro culture of vitrified goat ovarian cortex was able to promote follicle survival and did not alter the expression of SDF-1α and 43. However, the expression of Cx 37 was modified after in vitro culture of vitrified tissue.
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Affiliation(s)
- Nathalie Jiatsa Donfack
- Faculty of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil
| | - Kele Amaral Alves
- Faculty of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil
| | - Benner Geraldo Alves
- Faculty of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil
| | - Rebeca Magalhães Pedrosa Rocha
- Faculty of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil
| | - Jamily Bezzera Bruno
- Faculty of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil
| | - Marcelo Bertolini
- Laboratory of Molecular Biology and Development, University of Fortaleza (UNIFOR), CE, Brazil; Federal University of Rio Grande do Sul, Veterinay Faculty, Porto Alegre, RS, Brazil
| | | | | | - José Ricardo De Figueiredo
- Faculty of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil
| | - Johan Smitz
- Follicle Biology Laboratory, Center for Reproductive Medicine, UZ Brussel, Laarbeeklaan 101, B-1090, Brussels, Belgium
| | - Ana Paula Ribeiro Rodrigues
- Faculty of Veterinary Medicine, Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil.
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18
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Read CC, Willhelm G, Dyce PW. Connexin 43 coupling in bovine cumulus cells, during the follicular growth phase, and its relationship to in vitro embryo outcomes. Mol Reprod Dev 2018; 85:579-589. [PMID: 29697878 DOI: 10.1002/mrd.22993] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 04/24/2018] [Indexed: 12/11/2022]
Abstract
Gap junctional coupling between cumulus cells is required for oocytes to reach developmental competence. Multiple connexins, which form these gap junctions, have been found within the ovarian follicles of several species including bovine. The aim of this study was to determine the role of connexin 43 (CX43) and its relationship to embryo development, after in vitro fertilization (IVF). Cumulus-oocyte complexes (COCs) were obtained from abattoir sourced, mixed breed, bovine ovaries. COCs were isolated from follicles ranging from 2 to 5 mm in size, representing the preselected follicle pool. Immediately after isolation, two cumulus cell biopsies were collected and stored for analysis pending determination of developmental outcomes. Using in vitro procedures, COCs were individually matured, fertilized, and cultured to the blastocyst stage. Biopsies were grouped as originating from COCs that arrested at the two-cell stage (low developmental competence [LDC]) or having developed to the late morula/blastocyst stage (high developmental competence [HDC]), after IVF and embryo culture. The expression level of CX43 was found to be significantly higher in cumulus cells from COCs that had an HDC when compared with those that had an LDC. Moreover, the gap junctional intercellular coupling rate was significantly higher in cumulus from COCs deemed to have an HDC. Significantly higher expression of the cumulus health markers luteinizing hormone receptor and cytochrome p450 19A1 was found in the cumulus originating from oocytes with HDC, suggesting that this system may provide a mechanism for noninvasively testing for oocyte health in preselected bovine follicles.
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Affiliation(s)
- Casey C Read
- Department of Animal Sciences, College of Agriculture, Auburn University, Auburn, Alabama
| | - Gabby Willhelm
- Department of Animal Sciences, College of Agriculture, Auburn University, Auburn, Alabama
| | - Paul W Dyce
- Department of Animal Sciences, College of Agriculture, Auburn University, Auburn, Alabama
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19
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Cadoret V, Frapsauce C, Jarrier P, Maillard V, Bonnet A, Locatelli Y, Royère D, Monniaux D, Guérif F, Monget P. Molecular evidence that follicle development is accelerated in vitro compared to in vivo. Reproduction 2017; 153:493-508. [DOI: 10.1530/rep-16-0627] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 01/27/2017] [Accepted: 02/02/2017] [Indexed: 12/18/2022]
Abstract
In this study, we systematically compared the morphological, functional and molecular characteristics of granulosa cells and oocytes obtained by a three-dimensional in vitro model of ovine ovarian follicular growth with those of follicles recovered in vivo. Preantral follicles of 200 µm diameter were recovered and cultured up to 950 µm over a 20-day period. Compared with in vivo follicles, the in vitro culture conditions maintained follicle survival, with no difference in the rate of atresia. However, the in vitro conditions induced a slight decrease in oocyte growth rate, delayed antrum formation and increased granulosa cell proliferation rate, accompanied by an increase and decrease in CCND2 and CDKN1A mRNA expression respectively. These changes were associated with advanced granulosa cell differentiation in early antral follicles larger than 400 µm diameter, regardless of the presence or absence of FSH, as indicated by an increase in estradiol secretion, together with decreased AMH secretion and expression, as well as increased expression of GJA1, CYP19A1, ESR1, ESR2, FSHR, INHA, INHBA, INHBB and FST. There was a decrease in the expression of oocyte-specific molecular markers GJA4, KIT, ZP3, WEE2 and BMP15 in vitro compared to that in vivo. Moreover, a higher percentage of the oocytes recovered from cultured follicles 550 to 950 µm in diameter was able to reach the metaphase II meiosis stage. Overall, this in vitro model of ovarian follicle development is characterized by accelerated follicular maturation, associated with improved developmental competence of the oocyte, compared to follicles recovered in vivo.
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20
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Sampaio da Silva AM, Bruno JB, de Lima LF, Ribeiro de Sá NA, Lunardi FO, Ferreira ACA, Vieira Correia HH, de Aguiar FLN, Araújo VR, Lobo CH, de Alencar Araripe Moura A, Campello CC, Smitz J, de Figueiredo JR, Ribeiro Rodrigues AP. Connexin 37 and 43 gene and protein expression and developmental competence of isolated ovine secondary follicles cultured in vitro after vitrification of ovarian tissue. Theriogenology 2016; 85:1457-67. [PMID: 26876055 DOI: 10.1016/j.theriogenology.2016.01.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 12/01/2015] [Accepted: 01/04/2016] [Indexed: 12/25/2022]
Abstract
Cryoinjuries caused by vitrification of tissues and organs lead to the loss of membrane proteins that mediate intercellular communications, such as connexins 37 (Cx37) and 43 (Cx43). Thus, the present study aimed to evaluate ovine Cx37 and Cx43 gene and protein expressions and developmental competence by in vitro-cultured secondary follicles retrieved from vitrified ovarian tissue. Ovarian fragments for the same ovary pair were distributed into six treatments: (1) fresh ovarian tissue (FOT); (2) vitrified ovarian tissue (VOT); (3) isolated follicles from fresh ovarian tissue (FIF); (4) isolated follicles from vitrified ovarian tissue; (5) isolated follicles from fresh ovarian tissue followed by in vitro culture (CFIF); (6) isolated follicles from vitrified ovarian tissue followed by in vitro culture (CVIF). In all treatments, Cx37 and Cx43 gene and protein expression patterns were evaluated by reverse transcription polymerase chain reaction and immunocytochemistry. In addition, secondary follicles were analyzed according to follicular integrity and growth, apoptosis, and cell proliferation. In vitro-cultured secondary follicles (CFIF and CVIF) were evaluated based on morphology (extruded follicles), antrum formation, and viability. The percentage of intact follicles was higher, whereas antrum formation, oocyte extrusion rate, and follicle viability were lower in CVIF than in CFIF treatment (P < 0.05). Terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphates nick end-labeling assay demonstrated that apoptosis was absent in FIF, whereas follicles from all other treatments showed positive labeling. Cell proliferation index was higher in isolated follicles from vitrified ovarian tissue and CVIF treatments than in follicles from FIF. Expression of Cx43 messenger RNA was lower in CVIF treatment when compared with follicles from all other treatments (P < 0.05). Follicle Cx37 messenger RNA levels did not show alterations in any treatment (P > 0.05). Cx37 and Cx43 immunolabeling was localized mainly on granulosa cells and oocytes, respectively. In conclusion, isolation of ovine secondary follicles could be done successfully after vitrification of ovarian tissue, and the basement membrane integrity remained intact after in vitro culture. Although the gene and protein expression of Cx37 did not change after vitrification of ovarian tissue, Cx43 turned out to be altered in secondary follicles after vitrification and in vitro culture.
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Affiliation(s)
| | - Jamily Bezerra Bruno
- Faculty of Veterinary Medicine, LAMOFOPA, PPGCV, State University of Ceara, Fortaleza, Ceará, Brazil
| | - Laritza Ferreira de Lima
- Faculty of Veterinary Medicine, LAMOFOPA, PPGCV, State University of Ceara, Fortaleza, Ceará, Brazil
| | | | | | | | | | | | - Valdevane Rocha Araújo
- Faculty of Veterinary Medicine, LAMOFOPA, PPGCV, State University of Ceara, Fortaleza, Ceará, Brazil
| | - Carlos Henrique Lobo
- Group of Research in Biology of Reproduction, Department of Animal Science, Federal University of Ceará UFC, Fortaleza, Ceará, Brazil
| | - Arlindo de Alencar Araripe Moura
- Group of Research in Biology of Reproduction, Department of Animal Science, Federal University of Ceará UFC, Fortaleza, Ceará, Brazil
| | - Cláudio Cabral Campello
- Faculty of Veterinary Medicine, LAMOFOPA, PPGCV, State University of Ceara, Fortaleza, Ceará, Brazil
| | - Johan Smitz
- Follicle Biology Laboratory, Center for Reproductive Medicine, UZ Brussel, Brussels, Belgium
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21
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Importância das comunicações intercelulares para o desenvolvimento de folículos ovarianos. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.recli.2015.12.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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22
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Shimada M. Regulation of oocyte meiotic maturation by somatic cells. Reprod Med Biol 2012; 11:177-184. [PMID: 29662364 DOI: 10.1007/s12522-012-0130-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2012] [Accepted: 04/26/2012] [Indexed: 01/21/2023] Open
Abstract
In preovulatory follicles, each oocyte is surrounded by numerous layers of cumulus cells, forming the cumulus cell-oocyte complex. An LH surge induces meiotic resumption of the oocyte to progress to metaphase II. Because the expression of LH receptors is not detected in the oocyte and is minimal (negligible) in cumulus cells as compared with granulosa cells, secondary factors from granulosa cells are required to induce the ovulation process. One of the key factors secreted from granulosa cells is an EGF-like factor that activates the EGFR-ERK1/2 pathway in cumulus cells. The activated ERK1/2 pathway is not only involved in gene expression but also essential for the close of gap-junctional communication among cumulus cells and between cumulus cells and the oocyte. Closing gap-junctional communication decreases the amount of cGMP and/or cAMP to transfer into the oocyte, which requires activation of phosphodiesterase type III (PDE3) in the oocyte. PDE3 brakes down cAMP to decrease PKA activity in the oocyte. This decrease in PKA activity induces activation of CDK1 to resume meiosis from the germinal vesicle stage. Thus, the functions of cumulus cells that are regulated by granulosa cell-secreted factors are essential for oocyte meiotic resumption and maturation with developmental competence.
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Affiliation(s)
- Masayuki Shimada
- Laboratory of Reproductive Endocrinology, Graduate School of Biosphere Science Hiroshima University Higashi 739-8528 Hiroshima Hiroshima Japan
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23
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Grazul-Bilska AT, Vonnahme KA, Bilski JJ, Borowczyk E, Soni D, Mikkelson B, Johnson ML, Reynolds LP, Redmer DA, Caton JS. Expression of gap junctional connexin proteins in ovine fetal ovaries: effects of maternal diet. Domest Anim Endocrinol 2011; 41:185-94. [PMID: 21820266 PMCID: PMC3190047 DOI: 10.1016/j.domaniend.2011.06.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 06/15/2011] [Accepted: 06/20/2011] [Indexed: 12/20/2022]
Abstract
Gap junctions have been implicated in the regulation of cellular metabolism and the coordination of cellular functions during growth and differentiation of organs and tissues, and gap junctions play a major role in direct cell-cell communication. Gap junctional channels and connexin (Cx) proteins have been detected in adult ovaries in several species. Furthermore, it has been shown that several environmental factors, including maternal diet, may affect fetal organ growth and function. To determine whether maternal diet affects expression of Cx26, Cx32, Cx37, and Cx43 in fetal ovaries, sheep were fed a maintenance (M) diet with adequate (A) selenium (Se) or high (H) Se levels from 21 d before breeding to day 132 of pregnancy. From day 50 to 132 of pregnancy (tissue collection day), a portion of the ewes from the ASe and HSe groups was fed a restricted (R; 60% of M) diet. Sections of fetal ovaries were immunostained for the presence of Cxs followed by image analysis. All four Cxs were detected, but the distribution pattern differed. Cx26 was immunolocalized in the oocytes from primordial, primary, secondary, and antral follicles; in granulosa and theca layers of secondary and antral follicles; stroma; and blood vessels. Cx32 was in oocytes, granulosa, and theca cells in a portion of antral follicles; Cx37 was on the borders between oocyte and granulosa/cumulus cells of primordial to antral follicles and in endothelium; and Cx43 was on cellular borders in granulosa and theca layers and between oocyte and granulosa/cumulus cells of primordial to antral follicles. Maternal diet affected Cx26 and Cx43 expression, Cx26 in granulosa layer of antral follicles was decreased (P < 0.01) by HSe in the M and R diets, and Cx43 in granulosa layer of primary and granulosa and theca of antral follicles was increased (P < 0.05) by the M diet with HSe. Thus, Cxs may be differentially involved in regulation of fetal ovarian function in sheep. These data emphasize the importance of maternal diet in fetal growth and development.
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Affiliation(s)
- A T Grazul-Bilska
- Department of Animal Sciences, Center for Nutrition and Pregnancy, North Dakota State University, Fargo, 58108, USA.
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24
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Nitta M, Yogo K, Ohashi M, Akiyama M, Kunitomo Y, Ogawa T, Ishida-Kitagawa N, Miyoshi J, Sato E, Takeya T. Identification and expression analysis of connexin-45 and connexin-60 as major connexins in porcine oocytes. J Anim Sci 2010; 88:3269-79. [PMID: 20562362 DOI: 10.2527/jas.2009-2781] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
During mammalian oogenesis, intercellular communication between oocytes and the surrounding follicle cells through gap junction channels is crucial for oocyte development and maturation. The channel properties of gap junctions may be affected by the composition or combination of connexins, the expression of which is regulated by gonadotropins and other factors. Thus, identification and expression analysis of connexin genes in oocytes and follicle cells will help us to better understand how oogenesis and folliculogenesis are regulated in a species-specific manner in mammals. We previously reported the spatiotemporal expression of multiple connexin genes in porcine follicle cells. Here, we searched for connexin genes specifically expressed in porcine oocytes that may be involved in the formation of gap junctions between oocytes and follicle cells. To achieve this, we constructed an oocyte-specific cDNA library to identify which connexin genes are expressed in these cells and found that gap junction protein, alpha 10, which encodes connexin-60, and a porcine ortholog of mouse gap junction protein, gamma 1 encoding connexin-45, are the major connexins expressed in porcine oocytes during folliculogenesis. Immunostaining and in situ hybridization of sectioned porcine ovaries confirmed oocyte expression of these genes at 3 different stages of ovary development. Furthermore, their gap junction channel activity was assessed using a heterologous cell system. However, gap junction protein, alpha 4, which encodes connexin-37 and is expressed in the oocytes of several other mammals, was undetectable. We demonstrate that there is diversity in the connexin genes expressed in mammalian oocytes, and hence in the gap junctions connecting oocytes and cumulus cells.
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Affiliation(s)
- M Nitta
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara, Japan
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25
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Abstract
To evaluate gene expression of Connexin37 (Cx37) in oocytes from in vitro follicles at different stages, mouse preantral follicles were isolated and cultured for 12 days in vitro. Compared with in vitro follicles, follicles grown in vivo were collected at day 14 (d14), d16, d18, d20, d22 and d24 with the same stages for gene expression of Cx37 in oocytes. Our results showed that Cx37 mRNA increased along with follicular development, reached the highest level at the onset of antrum cavity formation and decreased after antrum formation in both in vivo and in vitro mouse oocytes. However, Cx37 mRNA was significant higher (p < 0.01) in in vitro cultured oocytes than in vivo oocytes. Moreover, significantly higher levels of Cx37 mRNA were found in oocytes from in vitro disrupted follicles (p < 0.01) and non-grown follicles (p < 0.05) than those from normal follicles with a similar size. These data determine temporal gene expression of Cx37 in oocytes from follicules at different stages and indicate that the gene expression level of Cx37 in oocytes could be evaluated as a criterion to the regulatory mechanism of Cx37 in an in vitro model.
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Affiliation(s)
- Bao Ying Yin
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi Province, People's Republic of China
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26
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Molecular cloning and evolutionary analysis of the GJA1 (connexin43) gene from bats (Chiroptera). Genet Res (Camb) 2009; 91:101-9. [DOI: 10.1017/s0016672309000032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
SummaryGap junction protein connexin43 (Cx43), encoded by the GJA1 gene, is the most abundant connexin in the cardiovascular system and was reported as a crucial factor maintaining cardiac electrical conduction, as well as having a very important function in facilitating the recycling of potassium ions from hair cells in the cochlea back into the cochlear endolymph during auditory transduction processes. In mammals, bats are the only taxon possessing powered flight, placing exceptional demand on many organismal processes. To meet the demands of flying, the hearts of bats show many specialties. Moreover, ultrasonic echolocation allows bat species to orientate and often detect and locate food in darkness. In this study, we cloned the full-length coding region of GJA1 gene from 12 different species of bats and obtained orthologous sequences from other mammals. We used the maximum likelihood method to analyse the evolution of GJA1 gene in mammals and the lineage of bats. Our results showed this gene is much conserved in mammals, as well as in bats' lineage. Compared with other mammals, we found one private amino acid substitution shared by bats, which is located on the inner loop domain, as well as some species-specific amino acid substitutions. The evolution rate analyses showed the signature of purifying selection on not only different classification level lineages but also the different domains and amino acid residue sites of this gene. Also, we suggested that GJA1 gene could be used as a good molecular marker to do the phylogenetic reconstruction.
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27
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Berisha B, Bridger P, Toth A, Kliem H, Meyer HHD, Schams D, Pfarrer C. Expression and localization of gap junctional connexins 26 and 43 in bovine periovulatory follicles and in corpus luteum during different functional stages of oestrous cycle and pregnancy. Reprod Domest Anim 2008; 44:295-302. [PMID: 19032438 DOI: 10.1111/j.1439-0531.2008.01068.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The aim of this study was to characterize the regulation of connexins (Cx26 and Cx43) in the bovine ovary (experiment 1-3). Experiment 1: ovaries containing preovulatory follicles or corpora lutea (CL) were collected at 0, 4, 10, 20, 25 (follicles) and 60 h (CL) relative to injection of GnRH. Experiment 2: CL were assigned to the following stages: days 1-2, 3-4, 5-7, 8-12, 13-16, >18 (after regression) of oestrous cycle and of early and late pregnancy (<4 and >4 months). Experiment 3: induced luteolysis, cows on days 8-12 were injected with PGF2alpha analogue (Cloprostenol), and CL were collected by transvaginal ovariectomy before and 0.5, 2, 4, 12, 24, 48 and 64 h after PGF2alpha injection. Real-time RT-PCR was applied to investigate mRNA expression and immunofluorescence was utilized for protein localization. Cx26 mRNA increased rapidly 4 h after GnRH injection (during LH surge) and decreased afterwards during the whole experimental period. Cx43 mRNA expression decreased continuously after GnRH application. Cx26 mRNA in CL increased significantly in the second part of oestrous cycle and after regression. In contrast, the highest mRNA expression for Cx43 in CL was detected during the early luteal phase. After induced luteolysis the mRNA expression of Cx26 increased significantly at 24 h. As shown by immunofluorescence, Cx26 was predominantly localized in the connective tissue and blood vessels of bovine CL, whereas Cx43 was present in the luteal cells and blood vessels. This resulted in a strong increase of Cx26 expression during the late luteal phase and after luteal regression. Subsequently, Cx43 expression was distinctly decreased after luteal regression. These data suggest that Cx26 and Cx43 are involved in the local cellular mechanisms participating in tissue remodelling during the critical time around periovulation as well as during CL formation (angiogenesis), function and regression in the bovine ovary.
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Affiliation(s)
- B Berisha
- Physiology Weihenstephan, Technical University Munich, Weihenstephaner Berg 3, Freising-Weihenstephan, Germany.
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28
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Development, molecular composition and freeze tolerance of bovine embryos cultured in TCM-199 supplemented with hyaluronan. ZYGOTE 2008; 16:39-47. [DOI: 10.1017/s0967199407004467] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
SummaryHyaluronan (HA) is glycosaminoglycan that is present from the start of embryonic development and its role and concentration increases with embryo development. The objective of this study was to evaluate if the presence of HA in TCM-199 culture medium had an effect on the development and quality of bovine embryos. There was no effect of HA on the total number of zygotes developing to blastocysts on day 7, however more expanded and hatched blastocyst stages were observed on days 8 and 9 in the group supplemented with HA (p< 0.05). Following freeze/thawing, significantly more (p< 0.05) embryos cultured in medium supplemented with HA hatched than those cultured in TCM-199 alone or those with BSA. Medium supplemented with HA and BSA significantly increased the level of expression of glucose metabolismGlut-1gene and embryo compactionCx43gene (p< 0.05), and had no effect onGlut-5andIGF-IIexpression. In addition, HA presence in culture decreased the level of expression of apoptosisBaxand oxidative stressSOXgenes (p< 0.05). There was significant difference in total number of nuclei between TCM-199 medium only and the remaining media containing BSA or HA plus BSA, between which there was no difference. In summary, our results indicate that the addition of high molecular weight HA to TCM-199 medium that contains BSA on day 4 of culture improved embryo development to hatching and hatched blastocysts and the quality of produced embryos, which were superior to embryos cultured without HA addition.
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Abstract
Gap junctions that allow the direct communication between cytoplasmic compartments of neighboring cells are present in a variety of tissues and organs and play pivotal roles in a wide range of physiological processes. In the ovary, gap junctions consist mainly of connexin (Cx) 43 and Cx37, and their indispensable role in regulating folliculogenesis and oogenesis is well established. The ovarian Cx43 is regulated by gonadotropins at the transcriptional, translational and post-translational levels whereas the regulation of the ovarian Cx37 is yet unknown. In addition to their involvement in normal ovarian functions, gap junction proteins, particularly Cx43, seem to act as cancer suppressors. A summary of our present knowledge regarding gap junctional communication (GJC) and the ovarian gap junction proteins in normally developing ovaries and under pathological conditions is presented in this review.
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Affiliation(s)
- Eran Gershon
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel
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30
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Willingham-Rocky LA, Golding MC, Wright JM, Kraemer DC, Westhusin ME, Burghardt RC. Cloning of GJA1 (connexin43) and its expression in canine ovarian follicles throughout the estrous cycle. Gene Expr Patterns 2007; 7:66-71. [PMID: 16829210 DOI: 10.1016/j.modgep.2006.05.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2006] [Revised: 05/07/2006] [Accepted: 05/25/2006] [Indexed: 11/29/2022]
Abstract
GJA1 (also known as connexin43 or Cx43) is the most abundant gap junction protein in mammalian tissues including the ovary. Here, it facilitates intercellular communication among granulosa cells and growing oocytes, thereby connecting the developing gamete to the hormonal axis as well as to the essential network of supporting granulosa cells. To date, the pattern of follicular GJA1 expression has not yet been defined for canines, a species with unique reproductive physiology including delays in follicle development, ovulation, oocyte maturation and fertilization. Here, we report the complete mRNA sequence for canine GJA1 and identify not only increases (P<0.05) in GJA1 mRNA expression in follicles at the secondary stage and larger, but also differences in expression levels between estrous cycle stages in both secondary and antral stage follicles. Expression of GJA1 mRNA in secondary follicles during proestrus was higher than in anestrus or estrus (P<0.01), and at diestrus (P<0.10). Antral follicles obtained during estrus expressed lower levels of GJA1 mRNA than any other cycle stage (P<0.01). GJA1 mRNA expression in primary and large antral follicles was similar across the estrous cycle. Despite the extensive length of the canine estrous cycle as compared with that of other mammals, the GJA1 mRNA and protein expression profiles are not significantly different from those reported for other species and suggests that mechanisms regulating GJA1 transcription are not likely to contribute to the extended delays in follicle and oocyte development in the dog.
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Affiliation(s)
- Lauri A Willingham-Rocky
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX, USA
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31
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Borowczyk E, Johnson ML, Bilski JJ, Borowicz PP, Redmer DA, Reynolds LP, Grazul-Bilska AT. Expression of gap junctional connexins 26, 32, and 43 mRNA in ovarian preovulatory follicles and corpora lutea in sheep. Can J Physiol Pharmacol 2006; 84:1011-20. [PMID: 17218967 DOI: 10.1139/y06-054] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The objective of the current study was to evaluate the expression of connexins (Cx)26, Cx32, and Cx43 mRNA in granulosa and theca cells during the peri-ovulatory period (experiment 1) and in the corpus luteum (CL) during the estrous cycle (experiment 2) and during prostaglandin F2alpha (PGF)-induced luteal regression (experiment 3) in FSH-treated ewes. In experiment 1, Cx26, Cx32, and Cx43 mRNA was expressed in granulosa and theca cells, and expression of Cx32 and Cx43 mRNA, but not Cx26, was greater (p<0.001) in granulosa than in theca cells throughout the peri-ovulatory period. Expression of Cx43 mRNA in granulosa and theca cells decreased (p<0.01) 24 h after hCG treatment. In experiment 2, expression of Cx26 mRNA in the CL tended to be greater (p<0.06) on day 10 than on days 5 or 15, but expression of Cx43 mRNA was greater (p<0.01) on day 5 than on days 10 and 15 of the estrous cycle. In experiment 3, expression of Cx26, but not Cx32 or Cx43 mRNA decreased (p<0.001) during PGF-induced luteal regression. In all 3 experiments, expression of Cx32 mRNA was much less than Cx26 and Cx43 mRNA. Moreover, Cx32 mRNA expression was unchanged during the peri-ovulatory period or during several stages of luteal development and PGF-induced regression of the CL. Thus, we have shown that the mRNA expression pattern of Cx26 and Cx43 changes during peri-ovulatory period and during several stages of the luteal development. This suggests that Cx26 and Cx43 play a role in ovarian tissue remodeling during the critical time around ovulation and throughout luteal tissue growth, differentiation, and regression in sheep.
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Affiliation(s)
- Ewa Borowczyk
- Department of Animal and Range Sciences, North Dakota State University, Fargo, ND 58105, USA
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32
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Barrios-de-Tomasi J, Nayudu PL, Brehm R, Heistermann M, Zariñán T, Ulloa-Aguirre A. Effects of human pituitary FSH isoforms on mouse follicles in vitro. Reprod Biomed Online 2006; 12:428-41. [PMID: 16740215 DOI: 10.1016/s1472-6483(10)61995-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The effects of human FSH glycoforms on mouse follicle development and function in vitro were analysed, and an attempt was made to relate markers of follicular maturation to the expression of immunolocalized connexin (Cx) 43 and Cx26-based gap junctions. Three FSH fractions comprising discrete pI ranges [7.10-5.99 (pool I), pI 5.62-4.95 (pool II) and <3.75 (pool III)] were studied. Pool I produced the strongest effect on preantral granulosa cell proliferation and oestradiol production, and was highly effective for stimulating antral formation; this isoform also evoked a peripheral distribution of Cx43-containing gap junctions. Pool II was effective in promoting preantral granulosa cell proliferation but required higher FSH doses. This particular isoform provoked a more central distribution of Cx43-containing gap junctions, which was associated with a lower oestradiol production and less effective antral formation. Pool III was the least active for all markers of follicle development, and this was associated with minimal induction of Cx43-based gap junctions. The effects of the three FSH isoform pools on Cx26 expression were similar. The pattern of differences strongly suggests that FSH isoforms have complementary and specific actions on developing follicles, and that a shifting stage specific balance of isoforms is required for optimal follicle development.
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Affiliation(s)
- J Barrios-de-Tomasi
- Research Unit in Reproductive Medicine, Hospital de Ginecoobstetricia 'Luis Castelazo Ayala', IMSS, Mexico City, Mexico
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Kaiser GG, Kölle S, Boie G, Sinowatz F, Palma GA, Alberio RH. In vivo effect of growth hormone on the expression of connexin-43 in bovine ovarian follicles. Mol Reprod Dev 2006; 73:600-6. [PMID: 16489623 DOI: 10.1002/mrd.20438] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This study assessed the in vivo effects of recombinant growth hormone (rGH) administration on the expression of connexin-43 (Cx43) in bovine ovarian follicles. Two independent experiments were carried out using either estrous unsynchronized or synchronized multiparous Aberdeen Angus cows. rGH-treated animals were inoculated with a single dose of hormone (500 mg, intramuscular) while control animals were inoculated with hormone diluent. Five and 14 days after treatment (Experiments 1 and 2, respectively), ovarian Cx43 and apoptosis expression were assessed using immunohistochemistry. In both experiments primary, secondary, and tertiary follicles from rGH-treated and control groups distinctly expressed Cx43 protein. Primordial and atretic follicles were Cx43-negative. Interestingly, the number of Cx43 dots per granulosa cell did not show significant variation at different folliculogenesis stages neither in the rGH-treated nor in the control group. In unsynchronized animals, Cx43-positive follicles per total number of follicles ratio showed an interaction between stage of folliculogenesis and treatment due to significant differences between treatment groups in the early secondary follicle stage. In synchronized animals, there were significant differences between treatment groups and folliculogenesis stage. In both experiments, atretic follicles showed apoptosis-related DNA-fragmentation as determined by terminal uridin nick end labeling (TUNEL) assay. Tertiary follicles presented moderate TUNEL staining. Our results show significant increment in the number of ovarian follicles expressing the gap junction subunit Cx43 after in vivo rGH treatment. Therefore, we conclude that growth hormone can modulate in vivo gap junction assembly at early stages of folliculogenesis.
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Affiliation(s)
- Germán G Kaiser
- Laboratorio de Biotecnología de la Reproducción, INTA, Balcarce, Argentina.
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34
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Pant D, Reynolds LP, Luther JS, Borowicz PP, Stenbak TM, Bilski JJ, Weigl RM, Lopes F, Petry K, Johnson ML, Redmer DA, Grazul-Bilska AT. Expression of connexin 43 and gap junctional intercellular communication in the cumulus-oocyte complex in sheep. Reproduction 2005; 129:191-200. [PMID: 15695613 DOI: 10.1530/rep.1.00434] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
To evaluate the effects of FSH, LH and/or cAMP on expression of connexin 43 (Cx43) in the ovine cumulus-oocyte complex (COC) and gap junctional intercellular communication (GJIC) of cumulus cells, two experiments were carried out. In experiment 1, Cx43 was immunodetected in the COC, before or after maturation, obtained from non-treated or FSH-treated ewes. The expression of Cx43 in the COC was greater (P < 0.01) on day 16 than on day 15 of the estrous cycle. In vivo FSH treatment decreased (P < 0.02) Cx43 expression on day 16 but not on day 15 of the estrous cycle. In experiment 2, intact COCs or isolated cumulus cells obtained from small and large follicles from FSH-treated ewes were cultured with or without FSH, LH or cAMP agonist and evaluated for GJIC by laser cytometry. For large follicles, the basal rate of GJIC was greater (P < 0.01) for cumulus cells in intact COCs than for isolated cumulus cells. FSH increased (P < 0.04) GJIC in cumulus cells in intact COCs and tended to increase (P < 0.1) GJIC in isolated cumulus cells from small follicles but decreased (P < 0.01) GJIC in cumulus cells in intact COCs from large follicles. LH also increased (P < 0.01) GJIC in isolated cumulus cells from small follicles but decreased GJIC in intact COCs (P < 0.01) and isolated cumulus cells (P < 0.02) from large follicles. cAMP increased (P < 0.01) the GJIC in both intact COCs and cumulus cells from small and large follicles. These results indicate that day of estrous cycle, stage of maturation and duration of FSH treatment affect expression of Cx43 in ovine COCs. In intact COCs, GJIC in cumulus cells was enhanced, probably due to the presence of the oocyte. In addition, the effects of FSH and LH, but not cAMP, on GJIC of cumulus cells depended on the stage of follicular development and on the presence of the oocyte.
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Affiliation(s)
- Disha Pant
- Department of Animal and Range Sciences, North Dakota State University, Fargo, ND 58105, USA
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Teilmann SC. Differential expression and localisation of connexin-37 and connexin-43 in follicles of different stages in the 4-week-old mouse ovary. Mol Cell Endocrinol 2005; 234:27-35. [PMID: 15836950 DOI: 10.1016/j.mce.2004.10.014] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2004] [Accepted: 10/18/2004] [Indexed: 11/17/2022]
Abstract
Mammalian female fertility is critically dependent on timely coordinated intercellular communication between follicle cells. Gap junctions are small, membrane-bound, aqueous channels that couple adjacent cells ionically and gap junction proteins, connexin-37 (Cx37) and connexin-43 (Cx43) both participate in sustaining proper growth and maturation of the oocyte. The purpose of the present study was to localise Cx37 and Cx43 in sections of ovarian mouse follicles of different developmental stage, and compare their relative expression using immunofluorescence and confocal microscopy. Cx37 exclusively localised to oocytes of all follicle stages, and the estimated number of Cx37 gap junctions per mum oocyte circumference in follicles of stage 2 to stage 6 increased in parallel to oocyte and follicle growth, reaching a maximum in the pre-antral stage. Acetylated alpha-tubulin and Cx37 double labelling revealed that the majority of Cx37 gap junctions, irrespective of follicle stage, were located on the outer surface of the oocyte cytoskeleton. Cx43 was detected in granulosa cells of all follicle stages, beginning with distinct spots in resting primordial follicles. The estimated number of Cx43 gap junctions per granulosa cell increased significantly with follicle development, in particular in the transition from pre-antral to the antral stage. A subpopulation of Cx43 in the outer part of the zona pellucida was identified and it is suggested these Cx43 gap junctions connect cumulus trans-zonal projections. Together, these data suggests specific roles for Cx37 and Cx43 in folliculogenesis and offers new insights in patterns of intercellular communication of the mouse follicle.
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Affiliation(s)
- Stefan Cuoni Teilmann
- Laboratory of Reproductive Biology, Juliane Marie Centre, Rigshospitalet section 5712, Blegdamsvej 9, DK-2100 Copenhagen, Denmark.
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Ndiaye K, Fayad T, Silversides DW, Sirois J, Lussier JG. Identification of downregulated messenger RNAs in bovine granulosa cells of dominant follicles following stimulation with human chorionic gonadotropin. Biol Reprod 2005; 73:324-33. [PMID: 15829623 DOI: 10.1095/biolreprod.104.038026] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Molecular determinants and mechanisms involved in ovarian follicular growth, ovulation, and luteinization are not well understood. The objective of this study was to identify genes expressed in bovine granulosa cells (GC) of dominant follicles (DF) and downregulated after hCG-induced ovulation, using the suppression subtractive hybridization (SSH). GC were collected from DF at Day 5 of the estrous cycle and from ovulatory follicles (OF) obtained 23 h following injection of hCG. A subtracted cDNA library (DF-OF) was generated and screened using unsubtracted (DF, OF) and subtracted (DF-OF, OF-DF) cDNAs as complex (32)P-probes. A total of 32 nonredundant cDNAs were identified: 23 cDNAs matched with sequences of known biological function and 9 cDNAs with complete or partial sequences of undefined biological function. Detection of genes known to be downregulated during the periovulatory period in the bovine species, such as CPD, CYP11A1, CYP19A1, FSHR, LRP8/ ApoER2, and SERPINE2, validated the physiological model and analytical techniques used. For a subset of genes, such as ARFGAP3, CYP11A1, CYP19A1, FSHR, FST, GJA1, IDH3, INHBA, LHCGR, LHCGR lacking exon 10, PRC1, PRG1, RPA2, SCD, and TRIB2, gene expression profiles were compared by virtual Northern blot or reverse transcriptase-polymerase chain reaction from follicles obtained at different developmental stages. Results confirmed a downregulation of the respective mRNAs in GC of OF compared with that of DF. We conclude that we have identified novel genes that are downregulated by hCG in bovine GC of DF during the periovulatory period, which may contribute to follicular growth, ovulation, and/or luteinization.
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Affiliation(s)
- Kalidou Ndiaye
- Centre de recherche en reproduction animale, Faculté de médecine vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada J2S 7C6
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37
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Calder MD, Caveney AN, Sirard MA, Watson AJ. Effect of serum and cumulus cell expansion on marker gene transcripts in bovine cumulus-oocyte complexes during maturation in vitro. Fertil Steril 2005; 83 Suppl 1:1077-85. [PMID: 15831278 DOI: 10.1016/j.fertnstert.2004.12.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2004] [Revised: 08/23/2004] [Accepted: 08/23/2004] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To determine the distribution of transcripts encoding the FSH receptor (FSHr), LH receptor (LHr), connexin 43 (Cx43), cyclooxygenase-2 (COX-2), and prostaglandin E(2) receptors 2 and 3 (EP2 and EP3) within bovine cumulus-oocyte complexes (COCs) and denuded oocytes and investigate the influence of gonadotropins, serum, and cumulus cell expansion on the abundance of transcripts encoding these genes. DESIGN Prospective controlled animal study. SETTING University research laboratory. PATIENT(S) Animal models for human studies. INTERVENTION(S) Cumulus-oocyte complexes were treated in culture with serum and gonadotropin-supplemented media to examine the effects to mRNA transcript levels. MAIN OUTCOME MEASURE(S) Variation in mRNA transcript levels. RESULT(S) Luteinizing hormone receptor, FSHr, and EP3 mRNAs were detected in intact COCs and not in cumulus cell-denuded oocytes, whereas Cx43, COX-2, and EP2 mRNAs were found in both COCs and oocytes. The relative abundance of marker gene mRNAs did not vary in media containing no additives or FSH alone, independent of whether the media induced cumulus cell expansion. However, the presence of serum in maturation media significantly decreased expression of all mRNAs except LHr. CONCLUSION(S) The relative abundance of COC mRNAs is altered by serum in the maturation medium, which may signify long-term consequences for embryonic development.
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Affiliation(s)
- Michele D Calder
- Department of Obstetrics and Gynecology, University of Western Ontario, London, Ontario, Canada.
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38
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Feranil JB, Isobe N, Nakao T. Expression of Gap Junction Protein Connexin 43 during Follicular Atresia in the Ovary of Swamp Buffaloes. J Reprod Dev 2005; 51:675-81. [PMID: 16034196 DOI: 10.1262/jrd.17009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The present study was performed to detect the presence of gap junction protein connexin 43 (Cx43) and describe the changes in its expression during ovarian follicular atresia in the swamp buffalo in comparison with cattle. Ovaries of Philippine swamp buffaloes (Bubalus bubalis; SB) and Holstein-Friesian cows (Bos taurus; HF) were collected from slaughterhouses, fixed in 10% formalin in PBS and embedded in paraffin. Sections of healthy follicles and at various follicular stages of atresia were immunostained with anti-Cx43 antibody. Cx43 appeared as punctate staining between granulosa cells (healthy to advanced atretic follicles), indicating assembled gap junctions, but was absent in the theca interna. In SB as well as in HF, granulosa cells showed a dense, moderate, and sparse immunoreactivity to Cx43 in healthy, early atretic, and advanced atretic follicles, respectively. Cumulus cells (in the advanced atretic follicle) surrounding oocytes and adjacent granulosa layers retain the Cx43 protein, although there was only a sparse expression of Cx43 observed in the granulosa layers distant from oocytes in the same follicles. The results indicate that gap junction protein Cx43 decreases in association with atresia and supports the concept that a loss of gap junctional communication plays a coordinating role in the process of atresia. Furthermore, the schema of Cx43 immunoreactivity in SB granulosa cells is similar to that of HF.
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Affiliation(s)
- Jun Babaan Feranil
- Laboratory of Animal Science, Graduate School for International Development and Cooperation, Hiroshima University, Higashi-Hiroshima, Japan
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39
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Dell'Aquila ME, Caillaud M, Maritato F, Martoriati A, Gérard N, Aiudi G, Minoia P, Goudet G. Cumulus expansion, nuclear maturation and connexin 43, cyclooxygenase-2 and FSH receptor mRNA expression in equine cumulus-oocyte complexes cultured in vitro in the presence of FSH and precursors for hyaluronic acid synthesis. Reprod Biol Endocrinol 2004; 2:44. [PMID: 15212696 PMCID: PMC446214 DOI: 10.1186/1477-7827-2-44] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2004] [Accepted: 06/22/2004] [Indexed: 03/30/2023] Open
Abstract
The aim of this study was to investigate cumulus expansion, nuclear maturation and expression of connexin 43, cyclooxygenase-2 and FSH receptor transcripts in equine cumuli oophori during in vivo and in vitro maturation in the presence of equine FSH (eFSH) and precursors for hyaluronic acid synthesis. Equine cumulus-oocyte complexes (COC) were cultured in a control defined medium supplemented with eFSH (0 to 5 micrograms/ml), Fetal Calf Serum (FCS), precursors for hyaluronic acid synthesis or glutamine according to the experiments. After in vitro maturation, the cumulus expansion rate was increased with 1 microgram/ml eFSH, and was the highest with 20% FCS. It was not influenced by precursors for hyaluronic acid synthesis or glutamine. The expression of transcripts related to cumulus expansion was analyzed in equine cumulus cells before maturation, and after in vivo and in vitro maturation, by using reverse transcription-polymerase chain reaction (RT-PCR) with specific primers. Connexin 43, cyclooxygenase-2 (COX-2) and FSH receptor (FSHr) mRNA were detected in equine cumulus cells before and after maturation. Their level did not vary during in vivo or in vitro maturation and was influenced neither by FSH nor by precursors for hyaluronic acid synthesis. Results indicate that previously reported regulation of connexin 43 and COX-2 proteins during equine COC maturation may involve post-transcriptional mechanisms.
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Affiliation(s)
- Maria Elena Dell'Aquila
- Department of Animal Production, University of Bari, Str. Prov. Casamassima, 70010 Valenzano (BA), Italy
| | - Maud Caillaud
- Unité de Physiologie de la Reproduction et des Comportements, UMR 6073 INRA-CNRS-Université F. Rabelais de Tours, 37380 Nouzilly, France
| | - Filippo Maritato
- Department of Animal Production, University of Bari, Str. Prov. Casamassima, 70010 Valenzano (BA), Italy
| | - Alain Martoriati
- Unité de Physiologie de la Reproduction et des Comportements, UMR 6073 INRA-CNRS-Université F. Rabelais de Tours, 37380 Nouzilly, France
| | - Nadine Gérard
- Unité de Physiologie de la Reproduction et des Comportements, UMR 6073 INRA-CNRS-Université F. Rabelais de Tours, 37380 Nouzilly, France
| | - Giulio Aiudi
- Department of Animal Production, University of Bari, Str. Prov. Casamassima, 70010 Valenzano (BA), Italy
| | - Paolo Minoia
- Department of Animal Production, University of Bari, Str. Prov. Casamassima, 70010 Valenzano (BA), Italy
| | - Ghylène Goudet
- Unité de Physiologie de la Reproduction et des Comportements, UMR 6073 INRA-CNRS-Université F. Rabelais de Tours, 37380 Nouzilly, France
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40
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Saez JC, Berthoud VM, Branes MC, Martinez AD, Beyer EC. Plasma membrane channels formed by connexins: their regulation and functions. Physiol Rev 2003; 83:1359-400. [PMID: 14506308 DOI: 10.1152/physrev.00007.2003] [Citation(s) in RCA: 867] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Members of the connexin gene family are integral membrane proteins that form hexamers called connexons. Most cells express two or more connexins. Open connexons found at the nonjunctional plasma membrane connect the cell interior with the extracellular milieu. They have been implicated in physiological functions including paracrine intercellular signaling and in induction of cell death under pathological conditions. Gap junction channels are formed by docking of two connexons and are found at cell-cell appositions. Gap junction channels are responsible for direct intercellular transfer of ions and small molecules including propagation of inositol trisphosphate-dependent calcium waves. They are involved in coordinating the electrical and metabolic responses of heterogeneous cells. New approaches have expanded our knowledge of channel structure and connexin biochemistry (e.g., protein trafficking/assembly, phosphorylation, and interactions with other connexins or other proteins). The physiological role of gap junctions in several tissues has been elucidated by the discovery of mutant connexins associated with genetic diseases and by the generation of mice with targeted ablation of specific connexin genes. The observed phenotypes range from specific tissue dysfunction to embryonic lethality.
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Affiliation(s)
- Juan C Saez
- Departamento de Ciencias Fisiológicas, Pontificia Universidad Católica de Chile, Alameda 340, Santiago, Chile.
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41
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Fayad T, Lévesque V, Sirois J, Silversides DW, Lussier JG. Gene expression profiling of differentially expressed genes in granulosa cells of bovine dominant follicles using suppression subtractive hybridization. Biol Reprod 2003; 70:523-33. [PMID: 14568916 DOI: 10.1095/biolreprod.103.021709] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Development of antral follicles beyond 3 to 4 mm in cattle appears as a wave pattern that occurs two to three times during the estrous cycle. Each wave presents a cyclic recruitment of multiple follicles at the 3- to 4-mm stage, followed by the selection of a single follicle that becomes the dominant follicle (DF). The molecular determinants involved in the follicular dominance process remain poorly understood. The objective of the current study was to compare gene expression in granulosa cells (GCs) between growing dominant follicles from Day 5 of the estrous cycle and nonselected small follicles (<or=4 mm) using the suppression subtractive hybridization (SSH) approach to identify candidate genes differentially expressed in GCs of the DF. Small follicle cDNAs were subtracted from DF cDNAs (DF-SF) and used to establish a DF GC-subtracted cDNA library. A total of 42 nonredundant cDNAs were identified. Detection of previously identified genes such as CX43, CYP19, INHBA, and SERPINE2 supported the validity of our experimental model and the use of SSH as the method of analysis. For selected genes such as ApoER2, CPD, CSPG2, 14-3-3 epsilon, NR5A2/SF2, RGN/SMP30, and SERPINE2, gene expression profiles were compared by virtual Northern blot or reverse transcriptase-polymerase chain reaction, and results confirmed an increase or induction of their mRNA in GCs of dominant follicles compared with that of small follicles. We conclude that we have identified novel genes (known and unknown) that are up-regulated in bovine GCs that may affect follicular growth, dominance, or both.
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Affiliation(s)
- Tania Fayad
- Centre de recherche en reproduction animale, Faculté de médecine vétérinaire, Université de Montréal, St-Hyacinthe, Québec, J2S 7C6, Canada
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42
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Abstract
At birth the ovaries of mammalian females contain a finite store of primordial follicle oocytes. Each oocyte and its surrounding follicle cells share a communication system, the gap junction network, which facilitates the transfer of signals as well as nutrients in to and out off the oocyte and between follicle cells. The connexin family of proteins form the building blocks of this communication network, their expression is specific to the differentiated state of the granulose cell and the stage of folliculogenesis. Factors such as the c-kit receptor and its ligand, IGF-I, IGF-I receptors and the IGF binding proteins, members of the transforming growth factor beta (TGFbeta) family, in particular, some of the bone morphogenetic proteins, play prominent roles in oogenesis, primordial follicle activation and subsequent follicle/oocyte development culminating in oocyte ovulation. The oocyte undergoes a progressive series of morphological modifications as it grows and proceeds through the different stages of development. These structural rearrangements facilitate the increasing energy and nucleic acid synthesis requirements of the developing oocyte and are a prerequisite to the oocytes achievement of meiotic and embryo developmental competence. Several factors determine the ultimate competence of the oocyte, these have been investigated and attempts made to mimic these conditions in vitro. The complexity of the orchestration of the events that control oocyte growth and ultimate acquisition of developmental competence is under continuous investigation. The present review describes some of the findings to date.
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Affiliation(s)
- Trudee Fair
- Department of Animal Science and Production and The Conway Institute for Biomedical and Biomolecular Research, University College Dublin, Lyons Research Farm, Newcastle, County Dublin, Ireland.
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43
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Kölle S, Stojkovic M, Boie G, Wolf E, Sinowatz F. Growth hormone-related effects on apoptosis, mitosis, and expression of connexin 43 in bovine in vitro maturation cumulus-oocyte complexes. Biol Reprod 2003; 68:1584-9. [PMID: 12606495 DOI: 10.1095/biolreprod.102.010264] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Pituitary LH and FSH are known to be the major regulators of ovarian function. In the last few years, however, there has been evidence that growth hormone (GH) is also involved in ovarian regulation. Therefore, the aim of our study was to elucidate the mechanisms of GH action during in vitro maturation (IVM) of bovine cumulus-oocyte complexes (COCs). As shown by detection of the nuclear cell proliferation-associated antigen Ki-67, COCs matured in vitro in the presence of GH revealed a significantly (P < 0.05) higher proportion of proliferating cumulus cells (12.6%) compared with the COCs matured in the control medium TCM 199 (9.9%). In contrast, the percentage of proliferating cells was not increased by supplementation of the medium with a combination of GH and insulin-like-growth factor I (IGF-I). Apoptosis as determined by TUNEL (terminal doxynucleotidyl transferase mediated dUTP nick-end labeling) was significantly (P < 0.05) reduced in the cumulus cells by GH treatment. COCs matured with a combination of GH and IGF-I revealed the lowest percentage of apoptotic cells (11%). The localization and quantification of the gap junction protein connexin 43 (Cx 43) demonstrated that GH induced a significant decrease in the synthesis of the Cx 43 protein in the cumulus cells. Our results imply that GH increases cumulus expansion by promotion of cell proliferation and inhibition of apoptosis. Whereas the increase in cell proliferation is a direct effect of GH, the antiapoptotic effects of GH during in vitro maturation are modulated by IGF-I. Stimulatory effects of GH on oocyte maturation are correlated with changes in the synthesis of gap junction proteins.
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Affiliation(s)
- Sabine Kölle
- Department of Veterinary Anatomy II, University of Munich, Germany.
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44
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Kennedy KL, Floyd AA, Clarkson AM, Lee VH. Epidermal growth factor regulation of connexin 43 in cultured granulosa cells from preantral rabbit follicles. Mol Reprod Dev 2003; 64:61-9. [PMID: 12420300 DOI: 10.1002/mrd.10219] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Connexin 43 (Cx43), a gap junction protein expressed in differentiated granulosa cells, is necessary for normal follicular development. Cx43 expression and regulation by epidermal growth factor (EGF) were characterized in immature rabbit granulosa cells. Cx43 mRNA was expressed in the granulosa cells of primary follicles, but was undetectable in primordial follicles. Abundant expression of Cx43 mRNA was maintained in the granulosa cells of growing follicles through maturity. Granulosa cells were isolated from early preantral follicles and maintained in monolayer cultures for 72 hr. After the first 24 hr of culture, they were maintained for 48 hr in serum-free medium supplemented with 0, 1, 5, or 10 ng/ml of mouse EGF. Granulosa cell proteins were isolated, solubilized, and evaluated for Cx43 by Western blot analysis using antibodies to rat Cx43. Relative amounts of Cx43 protein (both phosphorylated and nonphosphorylated) were increased (P < 0.05) by EGF in a dose-dependent manner. Northern blot analysis of RNA from cultured granulosa cells demonstrated increased amounts of Cx43 mRNA in the EGF treated cultures (10 ng EGF/ml) relative to controls (P < 0.03). In summary, Cx43 gap junctions are synthesized in granulosa cells following the onset of folliculogenesis in vivo and their expression is enhanced by EGF in vitro.
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Affiliation(s)
- Katie L Kennedy
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
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45
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Johnson ML, Redmer DA, Reynolds LP, Bilski JJ, Grazul-Bilska AT. Gap junctional intercellular communication of bovine granulosa and thecal cells from antral follicles: effects of luteinizing hormone and follicle-stimulating hormone. Endocrine 2002; 18:261-70. [PMID: 12450318 DOI: 10.1385/endo:18:3:261] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Throughout each estrous cycle, the gonadotropins, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), are involved in regulation of folliculogenesis. We have shown that LH or FSH affect cellular interactions mediated by gap junctions in bovine granulosa and thecal cells in vitro. To evaluate further the hypothesis that gonadotropins influence gap junctional intercellular communication (GJIC) and expression of gap junctional proteins known as connexins (Cx), throughout antral follicle development, granulosa and thecal cells from large (>10 mm; n = 13), medium (5-10 mm; n = 20), and small (<5 mm; n = 27) follicles were cultured (n = 4 cultures per size) with or without LH, FSH, or LH + FSH for 24 h. GJIC was evaluated (n = 125-150 cells/treatment group) by using the fluorescent recovery after photobleaching technique and laser cytometry. Additionally, Cx43, Cx32, and Cx26 were detected in cultured cells by immunocytochemistry and Cx43 by Western immunoblot analysis. Finally, progesterone production by cultured cells was evaluated by radioimmunoassay. Across all follicles and treatments, GJIC was greater (p < 0.01) for granulosa than thecal cells (4.9 +/- 0.05 vs 3.8 +/- 0.04%/min). For granulosa cells of large and medium follicles, LH and/or FSH did not affect GJIC. For granulosa cells of small follicles, FSH increased (p < 0.05), but LH or LH + FSH had no effect on GJIC. For thecal cells of large follicles, LH increased (p < 0.01) GJIC, whereas FSH or LH + FSH had no effects. For thecal cells of medium and small follicles, LH and/or FSH did not affect GJIC. These results demonstrate that FSH influenced GJIC of granulosa cells from small, but not from medium or large, follicles, and LH influenced GJIC of thecal cells from large, but not from medium or small, follicles. Cx43 was present as punctate staining between granulosa or thecal cells from all cultures, indicating assembled gap junctions. LH + FSH increased (p < 0.05) expression of Cx43 only by thecal cells from large follicles. Cx32 was detected in the perinuclear cytoplasm of cultured granulosa or thecal cells, and in the cytoskeleton of a few cells per culture dish in all sizes of follicles. Cx26 was present in a regular pattern throughout the cytoplasm of granulosa or thecal cells in all sizes of follicles. For granulosa cells from large follicles, progesterone production was stimulated (p < 0.05) with LH or FSH alone but was unaffected by LH + FSH. For granulosa cells from medium and small follicles, progesterone production was unaffected by LH and/or FSH. For thecal cells from all sizes of follicles, LH, FSH, and LH + FSH stimulated (p < 0.05) production of progesterone. These data indicate that LH and FSH influence gap junction function and expression, which likely contributes to the development and maintenance of ovarian follicles.
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46
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Abstract
The presented overview gives clear evidence for steroids as local regulators of follicular and luteal activity. In the follicle, estrogen receptor-alpha (ERalpha) and ERbeta expression are demonstrated in cow, ewe and pig. Besides species specific effects in general, there is evidence that estradiol-17beta (E(2)) exerts a dose-dependent inhibition on the secretion of progesterone (P(4)) by both theca interna cells (TI) and granulosa cells (GC). GC enhance the ability of the TI to produce androstendione by supplying them with progestin precursor. Androgen produced by TI enhances the ability of the GC to make E(2), and high concentrations of E(2) in the preovulatory follicle inhibit 3beta-HSD in both TI and GC and thus, may promote the use of the pathway Delta(5) for TI androgen production. The authors suggest that E(2) acts within the follicle to exert positive feedback on androgen and E(2) production, and exerts mitotic and anti-atretic or anti-apoptotic effects on follicular cells. Parts of the E(2)-mediated local action are regulated by stimulating effects on hormone receptors (LH, FSH, oxytocin). Gap junctions permit transfer of nutrients and cytokines to and from the avascular GC and oocyte, and formation is stimulated by estrogens. In bovine corpus luteum (CL) there is evidence that P(4) may directly regulate the production of P(4), oxytocin and prostaglandins (PGs) in a cycle dependent fashion. In most of domestic animal species, there is clear evidence for CL production of E(2) with clear stimulatory and luteotropic effects on P(4), and an intraluteal circuit that involves paracrine effects of E(2), oxytocin and PGF(2alpha) (especially in pigs). In contrast, there are species (ruminants, mares) in which the evidence for important local effects of E(2) is less clear, although expression of ERalpha, ERbeta and progesterone receptor (PR) is documented. Progesterone is very important for the regulation of CL lifetime by effects on the endometrium and release of the luteolytic signal PGF(2alpha). In conclusion, steroids as local regulators of ovarian activity are now documented and may stimulate further research in this field.
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Affiliation(s)
- D Schams
- Institute of Physiology, Technical University of Munich-Weihenstephan, D-85350 Freising, Germany.
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47
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Bolamba D, Floyd AA, McGlone JJ, Lee VH. Epidermal growth factor enhances expression of connexin 43 protein in cultured porcine preantral follicles. Biol Reprod 2002; 67:154-60. [PMID: 12080012 DOI: 10.1095/biolreprod67.1.154] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Connexin 43 (Cx43) and gap junctional coupling appear to play a critical role in early follicular development because absence of Cx43 disrupts progression of follicles beyond primary stages in transgenic mouse ovaries. Two experimental culture systems were used to determine whether epidermal growth factor (EGF) stimulates expression of Cx43 in early porcine follicular development. Ovarian explants were collected from 32- to 40-day-old gilts and cultured for 6 days on membrane inserts in Waymouth MB 752/1 medium supplemented with 0, 50, or 500 ng/ml mouse EGF. Western blot analysis demonstrated significant increases (P < 0.05) in relative amounts of Cx43 protein (both phosphorylated and nonphosphorylated) with 50 and 500 ng/ml of EGF as compared with control cultures. Preantral follicles were enzymatically isolated from 70- to 86-day-old gilts and cultured for 8 days in collagen matrices. Medium and EGF treatments were the same as previously described. Western blot analysis demonstrated a significant increase (P < 0.05) in relative amounts of Cx43 protein with 50 and 500 ng/ml of EGF as compared with control cultures. EGF increased expression of Cx43 protein in secondary preantral follicles in a dose-dependent manner, which suggests that EGF or similar growth factor molecules may modulate early folliculogenesis by stimulating expression of Cx43 gap junctions.
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Affiliation(s)
- Digbo Bolamba
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, USA
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48
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Nuttinck F, Reinaud P, Tricoire H, Vigneron C, Peynot N, Mialot JP, Mermillod P, Charpigny G. Cyclooxygenase-2 is expressed by cumulus cells during oocyte maturation in cattle. Mol Reprod Dev 2002; 61:93-101. [PMID: 11774380 DOI: 10.1002/mrd.1135] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Prostaglandins could be involved in various aspects of final differentiation of ovarian follicles. Prostaglandins are generated by the cyclooxygenase (cox) pathway. Until now, the expression pattern of isoforms cox-1 and cox-2 of cyclooxygenase in bovine cumulus-oocyte complexes (COCs) was unknown. Using immunodetection procedure, we demonstrated in the present study that cox-2 was expressed by cumulus cells during in vivo and in vitro maturation. Time course induction of cox-2 expression was investigated during in vitro maturation using Western blot analysis. Specific signal of cox-2 was markedly evidenced from 6 hr of culture and increased to reach a maximal level at 24 hr of culture. In vitro, cox-2 expression in COCs was associated with increased concentrations of PGE(2) and PGF(2alpha) in the maturation medium. In addition, the effects of culture conditions on cox-2 expression was considered using RT-PCR and Western-blot analysis. We demonstrated that the addition of 10 ng/ml of EGF to TCM199 clearly increased the expression level of cox-2 mRNA and protein. Higher levels of in vitro cox-2 expression was associated with greater rates of cumulus expansion and oocytes at metaphase II at 24 hr of culture. In conclusion, our present results suggest that cox-2 expression in cumulus cells may be involved in differentiation of COCs that occurs during oocyte maturation.
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Affiliation(s)
- F Nuttinck
- Ecole Nationale Vétérinaire d'Alfort, Unité de Biologie de la Reproduction, Maisons-Alfort, France.
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49
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Melton CM, Zaunbrecher GM, Yoshizaki G, Patiño R, Whisnant S, Rendon A, Lee VH. Expression of connexin 43 mRNA and protein in developing follicles of prepubertal porcine ovaries. Comp Biochem Physiol B Biochem Mol Biol 2001; 130:43-55. [PMID: 11470443 DOI: 10.1016/s1096-4959(01)00403-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A major form of cell-cell communication is mediated by gap junctions, aggregations of intercellular channels composed of connexins (Cxs), which are responsible for exchange of low molecular weight (<1200 Da) cytosolic materials. These channels are a growing family of related proteins. This study was designed to determine the ontogeny of connexin 43 (Cx43) during early stages of follicular development in prepubertal porcine ovaries. A partial-length (412 base) cDNA clone was obtained from mature porcine ovaries and determined to have 98% identity with published porcine Cx43. Northern blot analysis demonstrated a 4.3-kb mRNA in total RNA isolated from prepubertal and adult porcine ovaries. In-situ hybridization revealed that Cx43 mRNA was detectable in granulosa cells of primary follicles but undetectable in dormant primordial follicles. The intensity of the signal increased with follicular growth and was greatest in the large antral follicles. Immunohistochemical evaluation indicated that Cx43 protein expression correlated with the presence of Cx43 mRNA. These results indicate that substantial amounts of Cx43 are first expressed in granulosa cells following activation of follicular development and that this expression increases throughout follicular growth and maturation. These findings suggest an association between the enhancement of intercellular gap-junctional communication and onset of follicular growth.
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Affiliation(s)
- C M Melton
- Department of Animal Science and Food Technology, Texas Tech University, Lubbock, TX 79406, USA
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