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Yang R, Ji CL, Zhang M, Zhang J, Yuan HJ, Luo MJ, Jiao GZ, Tan JH. Role of calcium-sensing receptor in regulating activation susceptibility of postovulatory aging mouse oocytes. J Reprod Dev 2023; 69:185-191. [PMID: 37245986 PMCID: PMC10435528 DOI: 10.1262/jrd.2023-026] [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: 03/17/2023] [Accepted: 05/02/2023] [Indexed: 05/30/2023] Open
Abstract
The mechanisms underlying postovulatory oocyte aging (POA) remain largely unknown. The expression of the calcium-sensing receptor (CaSR) in mouse oocytes and its role in POA need to be explored. Our objective was to observe CaSR expression and its role in the susceptibility to activating stimuli (STAS) in POA mouse oocytes. The results showed that, although none of the newly ovulated oocytes were activated, 40% and 94% of the oocytes recovered 19 and 25 h after human chorionic gonadotropin (hCG) injection were activated, respectively, after ethanol treatment. The level of the CaSR functional dimer protein in oocytes increased significantly from 13 to 25 h post hCG. Thus, the CaSR functional dimer level was positively correlated with the STAS of POA oocytes. Aging in vitro with a CaSR antagonist suppressed the elevation of STAS, and cytoplasmic calcium in oocytes recovered 19 h post hCG, whereas aging with a CaSR agonist increased STAS, and cytoplasmic calcium of oocytes recovered 13 h post hCG. Furthermore, the CaSR was more important than the Na-Ca2+ exchanger in regulating oocyte STAS, and T- and L-type calcium channels were inactive in aging oocytes. We conclude that the CaSR is involved in regulating STAS in POA mouse oocytes, and that it is more important than the other calcium channels tested in this connection.
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Affiliation(s)
- Rui Yang
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City 271018, Shandong, P. R. China
- Laboratory Animal Center, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan 250021, Shandong, P. R. China
| | - Chang-Li Ji
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City 271018, Shandong, P. R. China
| | - Min Zhang
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City 271018, Shandong, P. R. China
| | - Jie Zhang
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City 271018, Shandong, P. R. China
| | - Hong-Jie Yuan
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City 271018, Shandong, P. R. China
| | - Ming-Jiu Luo
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City 271018, Shandong, P. R. China
| | - Guang-Zhong Jiao
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City 271018, Shandong, P. R. China
- Department of Reproductive Medicine, the Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai City 264000, Shandong Province, P. R. China
| | - Jing-He Tan
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an City 271018, Shandong, P. R. China
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Liu H, Zhou D, Liu C, Zhuan Q, Luo Y, Mo X, Fu X, Hou Y. The Calcium-Sensing Receptor Is Involved in Follicle-Stimulating Hormone-Induced Cumulus Expansion in in vitro Cultured Porcine Cumulus-Oocyte Complexes. Front Cell Dev Biol 2021; 9:625036. [PMID: 34095106 PMCID: PMC8173154 DOI: 10.3389/fcell.2021.625036] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 04/07/2021] [Indexed: 12/02/2022] Open
Abstract
The Calcium-Sensing Receptor (CASR) is a G protein-coupled receptor of the C family that reportedly promotes maturation of porcine oocytes. However, its role in cumulus expansion of cumulus-oocyte complexes (COCs) is not well known. This study was conducted to determine the role of CASR and potential mechanisms involved during in vitro maturation (IVM) of porcine COCs. After culture of COCs in follicle-stimulating hormone (FSH)-supplement maturation medium for 24 h, the time of breakdown of the germinal vesicle (GVBD), indicative of initiation of meiotic maturation, resulted in an increased (p < 0.05) CASR mRNA expression level in cumulus cells. Moreover, IVM of COCs in 10 μM of the CASR agonist NPS R-568 promoted (p < 0.05) cumulus expansion but only in FSH-containing medium. Conversely, 20 μM of the CASR inhibitor NPS2390 precluded cumulus expansion. We next tested the effect of the CASR agonist/inhibitor on the expression of cumulus expansion-related genes. The CASR agonist significantly upregulated the expression of hyaluronan acid synthase 2 (HAS2), whereas the CASR inhibitor downregulated the expression of all HAS2, prostaglandin-endoperoxide synthase 2 (PTGS2), and tumor necrosis factor a-induced protein 6 (TNFAIP6). Altogether, these results suggest that CASR activity is involved in FSH-stimulated porcine cumulus expansion.
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Affiliation(s)
- Huage Liu
- Institute of Reproductive Medicine, Nantong University, Nantong, China.,State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Dan Zhou
- Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Cong Liu
- School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Qingrui Zhuan
- Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Yan Luo
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Xianhong Mo
- College of Life Sciences, Chifeng University, Chifeng, China
| | - Xiangwei Fu
- Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Yunpeng Hou
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
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Sagvekar P, Kumar P, Mangoli V, Desai S, Mukherjee S. DNA methylome profiling of granulosa cells reveals altered methylation in genes regulating vital ovarian functions in polycystic ovary syndrome. Clin Epigenetics 2019; 11:61. [PMID: 30975191 PMCID: PMC6458760 DOI: 10.1186/s13148-019-0657-6] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 03/27/2019] [Indexed: 12/12/2022] Open
Abstract
Background Women with polycystic ovary syndrome (PCOS) manifest a host of ovarian defects like impaired folliculogenesis, anovulation, and poor oocyte quality, which grossly affect their reproductive health. Addressing the putative epigenetic anomalies that tightly regulate these events is of foremost importance in this disorder. We therefore aimed to carry out DNA methylome profiling of cumulus granulosa cells and assess the methylation and transcript expression profiles of a few differentially methylated genes contributing to ovarian defects in PCOS. A total of 20 controls and 20 women with PCOS were selected from a larger cohort of women undergoing IVF, after carefully screening their sera and follicular fluids for hormonal and biochemical parameters. DNA extracted from cumulus granulosa cells of three women each, from control and PCOS groups was subjected to high-throughput, next generation bisulfite sequencing, using the Illumina HiSeq 2500® platform. Remaining samples were used for the validation of methylation status of some identified genes by pyrosequencing, and the transcript expression profiles of these genes were assessed by quantitative real-time PCR. Results In all, 6486 CpG sites representing 3840 genes associated with Wnt signaling, G protein receptor, endothelin/integrin signaling, angiogenesis, chemokine/cytokine-mediated inflammation, etc., showed differential methylation in PCOS. Hypomethylation was noted in 2977 CpGs representing 2063 genes while 2509 CpGs within 1777 genes showed hypermethylation. Methylation differences were also noted in noncoding RNAs regulating several ovarian functions that are dysregulated in PCOS. Few differentially methylated genes such as aldo-keto reductase family 1 member C3, calcium-sensing receptor, resistin, mastermind-like domain 1, growth hormone-releasing hormone receptor and tumor necrosis factor, which predominantly contribute to hyperandrogenism, premature luteolysis, and oocyte development defects, were explored as novel epigenetic candidates in mediating ovarian dysfunction. Methylation profiles of these genes matched with our NGS findings, and their transcript expression patterns correlated with the gene hypo- or hypermethylation status. Conclusion Our findings suggest that the epigenetic dysregulation of genes involved in important processes associated with follicular development may contribute to ovarian defects observed in women with PCOS. Electronic supplementary material The online version of this article (10.1186/s13148-019-0657-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Pooja Sagvekar
- Department of Molecular Endocrinology, ICMR-National Institute for Research in Reproductive Health, J.M. Street, Parel, Mumbai, Maharashtra, 400012, India
| | - Pankaj Kumar
- Colin Jamura Lab, Institute for Stem Cell Biology and Regenerative Medicine (inStem), National Centre for Biological Sciences (NCBS), GKVK, Bellary Road, Bangalore, 560065, India
| | - Vijay Mangoli
- Fertility Clinic and IVF Center, 12-Springfield, 19-Vachha Gandhi Road, Gamdevi, Mumbai, Maharashtra, 400007, India
| | - Sadhana Desai
- Fertility Clinic and IVF Center, 12-Springfield, 19-Vachha Gandhi Road, Gamdevi, Mumbai, Maharashtra, 400007, India
| | - Srabani Mukherjee
- Department of Molecular Endocrinology, ICMR-National Institute for Research in Reproductive Health, J.M. Street, Parel, Mumbai, Maharashtra, 400012, India.
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Liu C, Liu Y, Larsen K, Hou YP, Callesen H. Calcium-sensing receptor (CASR) is involved in porcine in vitro fertilisation and early embryo development. Reprod Fertil Dev 2018; 30:391-398. [PMID: 28712411 DOI: 10.1071/rd16338] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Accepted: 06/25/2017] [Indexed: 11/23/2022] Open
Abstract
It has been demonstrated that extracellular calcium is necessary in fertilisation and embryo development but the mechanism is still not well understood. The present study mainly focussed on the extracellular calcium effector called the calcium-sensing receptor (CASR) and examined its expression in porcine gametes and embryos and its function during fertilisation and early embryo development. By using reverse transcription polymerase chain reaction, CASR was found to be expressed in porcine oocytes, spermatozoa and embryos at different developmental stages. Functionally, medium supplementation with a CASR agonist or an antagonist during in vitro fertilisation (IVF) and in vitro culture (IVC) was tested. During fertilisation, the presence of a CASR agonist increased sperm penetration rate and decreased polyspermy rate leading to an increased normal fertilisation rate. During embryo development, for the IVF embryos, agonist treatment during IVC significantly increased cleavage rate and blastocyst formation rate compared with the control group. Furthermore, parthenogenetically activated embryos showed similar results with lower cleavage and blastocyst formation rates in the antagonist group than in the other groups. It was concluded that CASR, as the effector of extracellular calcium, modulates porcine fertilisation and early embryo development.
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Affiliation(s)
- C Liu
- State Key Laboratory for Agrobiotechnology, College of Biological Sciences, China Agricultural University, No. 2, Yuanmingyuan West Road, Haidian District, Beijing 100193, China
| | - Y Liu
- Department of Animal Science, Aarhus University, Blichers Allé 20, DK-8830 Tjele, Denmark
| | - K Larsen
- Department of Molecular Biology and Genetics, Aarhus University, Blichers Allé 20, DK-8830 Tjele, Denmark
| | - Y P Hou
- State Key Laboratory for Agrobiotechnology, College of Biological Sciences, China Agricultural University, No. 2, Yuanmingyuan West Road, Haidian District, Beijing 100193, China
| | - H Callesen
- Department of Animal Science, Aarhus University, Blichers Allé 20, DK-8830 Tjele, Denmark
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5
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Do Gametes Woo? Evidence for Their Nonrandom Union at Fertilization. Genetics 2018; 207:369-387. [PMID: 28978771 DOI: 10.1534/genetics.117.300109] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 07/10/2017] [Indexed: 12/18/2022] Open
Abstract
A fundamental tenet of inheritance in sexually reproducing organisms such as humans and laboratory mice is that gametes combine randomly at fertilization, thereby ensuring a balanced and statistically predictable representation of inherited variants in each generation. This principle is encapsulated in Mendel's First Law. But exceptions are known. With transmission ratio distortion, particular alleles are preferentially transmitted to offspring. Preferential transmission usually occurs in one sex but not both, and is not known to require interactions between gametes at fertilization. A reanalysis of our published work in mice and of data in other published reports revealed instances where any of 12 mutant genes biases fertilization, with either too many or too few heterozygotes and homozygotes, depending on the mutant gene and on dietary conditions. Although such deviations are usually attributed to embryonic lethality of the underrepresented genotypes, the evidence is more consistent with genetically-determined preferences for specific combinations of egg and sperm at fertilization that result in genotype bias without embryo loss. This unexpected discovery of genetically-biased fertilization could yield insights about the molecular and cellular interactions between sperm and egg at fertilization, with implications for our understanding of inheritance, reproduction, population genetics, and medical genetics.
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Ellinger I. The Calcium-Sensing Receptor and the Reproductive System. Front Physiol 2016; 7:371. [PMID: 27625611 PMCID: PMC5003915 DOI: 10.3389/fphys.2016.00371] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 08/11/2016] [Indexed: 12/14/2022] Open
Abstract
Active placental transport of maternal serum calcium (Ca2+) to the offspring is pivotal for proper development of the fetal skeleton as well as various organ systems. Moreover, extracellular Ca2+ levels impact on distinct processes in mammalian reproduction. The calcium-sensing receptor (CaSR) translates changes in extracellular Ca2+-concentrations into cellular reactions. This review summarizes current knowledge on the expression of CaSR and its putative functions in reproductive organs. CaSR was detected in placental cells mediating materno-fetal Ca2+-transport such as the murine intraplacental yolk sac (IPYS) and the human syncytiotrophoblast. As shown in casr knock-out mice, ablation of CaSR downregulates transplacental Ca2+-transport. Receptor expression was reported in human and rat ovarian surface epithelial (ROSE) cells, where CaSR activation stimulates cell proliferation. In follicles of various species a role of CaSR activation in oocyte maturation was suggested. Based on studies in avian follicles, the activation of CaSR expressed in granulosa cells may support the survival of follicles after their selection. CaSR in rat and equine sperms was functionally linked to sperm motility and sperm capacitation. Implantation involves complex interactions between the blastocyst and the uterine epithelium. During early pregnancy, CaSR expression at the implantation site as well as in decidual cells indicates that CaSR is important for blastocyst implantation and decidualization in the rat uterus. Localization of CaSR in human extravillous cytotrophoblasts suggests a role of CaSR in placentation. Overall, evidence for functional involvement of CaSR in physiologic mammalian reproductive processes exists. Moreover, several studies reported altered expression of CaSR in cells of reproductive tissues under pathologic conditions. However, in many tissues we still lack knowledge on physiological ligands activating CaSR, CaSR-linked G-proteins, activated intracellular signaling pathway, and functional relevance of CaSR activation. Clearly, more work is required in the future to decode the complex physiologic and pathophysiologic relationship of CaSR and the mammalian reproductive system.
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Affiliation(s)
- Isabella Ellinger
- Pathophysiology of the Placenta, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University Vienna Vienna, Austria
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7
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Macías-García B, Rocha A, González-Fernández L. Extracellular calcium regulates protein tyrosine phosphorylation through calcium-sensing receptor (CaSR) in stallion sperm. Mol Reprod Dev 2016; 83:236-45. [DOI: 10.1002/mrd.22615] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 01/11/2016] [Indexed: 12/27/2022]
Affiliation(s)
- Beatriz Macías-García
- CECA/ICETA: Centro de Estudos de Ciência Animal/Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto; University of Porto; Portugal
- ICBAS: Instituto de Ciências Biomédicas Abel Salazar; University of Porto; Portugal
| | - Antonio Rocha
- CECA/ICETA: Centro de Estudos de Ciência Animal/Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto; University of Porto; Portugal
- ICBAS: Instituto de Ciências Biomédicas Abel Salazar; University of Porto; Portugal
| | - Lauro González-Fernández
- CECA/ICETA: Centro de Estudos de Ciência Animal/Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto; University of Porto; Portugal
- ICBAS: Instituto de Ciências Biomédicas Abel Salazar; University of Porto; Portugal
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Martino NA, Lange-Consiglio A, Cremonesi F, Valentini L, Caira M, Guaricci AC, Ambruosi B, Sciorsci RL, Lacalandra GM, Reshkin SJ, Dell'Aquila ME. Functional expression of the extracellular calcium sensing receptor (CaSR) in equine umbilical cord matrix size-sieved stem cells. PLoS One 2011; 6:e17714. [PMID: 21437284 PMCID: PMC3060090 DOI: 10.1371/journal.pone.0017714] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Accepted: 02/10/2011] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND The present study investigates the effects of high external calcium concentration ([Ca(2+)](o)) and the calcimimetic NPS R-467, a known calcium-sensing receptor (CaSR) agonist, on growth/proliferation of two equine size-sieved umbilical cord matrix mesenchymal stem cell (eUCM-MSC) lines. The involvement of CaSR on observed cell response was analyzed at both the mRNA and protein level. METHODOLOGY/PRINCIPAL FINDINGS A large (>8 µm in diameter) and a small (<8 µm) cell line were cultured in medium containing: 1) low [Ca(2+)](o) (0.37 mM); 2) high [Ca(2+)](o) (2.87 mM); 3) NPS R-467 (3 µM) in presence of high [Ca(2+)](o) and 4) the CaSR antagonist NPS 2390 (10 µM for 30 min.) followed by incubation in presence of NPS R-467 in medium with high [Ca(2+)](o). Growth/proliferation rates were compared between groups. In large cells, the addition of NPS R-467 significantly increased cell growth whereas increasing [Ca(2+)](o) was not effective in this cell line. In small cells, both higher [Ca(2+)](o) and NPS R-467 increased cell growth. In both cell lines, preincubation with the CaSR antagonist NPS 2390 significantly inhibited the agonistic effect of NPS R-467. In both cell lines, increased [Ca(2+)](o) and/or NPS R-467 reduced doubling time values.Treatment with NPS R-467 down-regulated CaSR mRNA expression in both cell lines. In large cells, NPS R-467 reduced CaSR labeling in the cytosol and increased it at cortical level. CONCLUSIONS/SIGNIFICANCE In conclusion, calcium and the calcimimetic NPS R-467 reduce CaSR mRNA expression and stimulate cell growth/proliferation in eUCM-MSC. Their use as components of media for eUCM-MSC culture could be beneficial to obtain enough cells for down-stream purposes.
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Affiliation(s)
- Nicola Antonio Martino
- Department of Animal Production, Faculty of Biotechnological Sciences, University of Bari, Valenzano, Bari, Italy.
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De Santis T, Casavola V, Reshkin SJ, Guerra L, Ambruosi B, Fiandanese N, Dalbies-Tran R, Goudet G, Dell'Aquila ME. The extracellular calcium-sensing receptor is expressed in the cumulus-oocyte complex in mammals and modulates oocyte meiotic maturation. Reproduction 2009; 138:439-52. [PMID: 19494043 DOI: 10.1530/rep-09-0078] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The extracellular calcium-sensing receptor (CASR) plays an important role in cells involved in calcium (Ca2+) homeostasis by directly sensing changes in the extracellular Ca2+ ion concentration. We previously reported the localization and quantitative expression of CASR protein in human oocytes. In this study, we examined the expression and the functional role of CASR during oocyte meiotic maturation in a large mammal animal model, the horse. As in humans, CASR protein was found to be expressed in equine oocytes and cumulus cells. Western-blot analysis revealed a single 130 kDa band in denuded oocytes and a doublet of 130-120 kDa in cumulus cells. CASR labeling was observed by confocal microscopy in cumulus cells and in oocytes on the plasma membrane and within the cytoplasm at all examined stages of meiosis. Functionally, the CASR allosteric effector NPS R-467, in the presence of 2.92 mM external Ca2+, increased oocyte maturation rate in a dose-dependent manner and its stimulatory effect was attenuated by pre-treatment with the CASR antagonist NPS 2390. NPS R-467 had no effect in suboptimal external Ca2+ (0.5 mM), indicating that it requires higher external Ca2+ to promote oocyte maturation. In oocytes treated with NPS R-467, CASR staining increased at the plasmalemma and was reduced in the cytosol. Moreover, NPS R-467 increased the activity of MAPK, also called ERK, in cumulus cells and oocytes. These results provide evidence of a novel signal transduction pathway modulating oocyte meiotic maturation in mammals in addition to the well-known systemic hormones.
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Affiliation(s)
- Teresa De Santis
- Department of Animal Production, University of Bari, 70010 Valenzano, Bari, Italy
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Hammond CM, White D, Tomic J, Shi Y, Spaner DE. Extracellular calcium sensing promotes human B-cell activation and function. Blood 2007; 110:3985-95. [PMID: 17724142 DOI: 10.1182/blood-2007-05-088468] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Calcium is a second messenger for many signaling pathways in B cells, but its role as a receptor ligand has not been well characterized. However, pulses of free calcium were found to cause the rapid release of internal calcium stores in normal human B cells. This response appeared to be mediated by a cell surface protein with receptor properties as it could be blocked by pretreatment with trypsin and with kinase and phospholipase Cgamma inhibitors. The calcium receptor on B cells was not the conventional calcium-sensing receptor (CaSR) since B cells did not express CaSR and calcium-induced responses could not be blocked by specific CaSR inhibitors. B-cell responses to extracellular calcium activated phosphoinositide-3 kinase/AKT, calcineurin, extracellular signal regulated kinase, p38 mitogen-activated protein kinase, protein kinase C, Ca(2+)/calmodulin kinase II, and nuclear factor-kappaB signaling pathways, and resulted in transcription of the early response gene, CD83. This extracellular calcium sensor enhanced B-cell responses to Toll-like receptor, B-cell receptor, and cytokine receptor agonists. These findings suggest a means by which B cells prepare to engage in immune responses by responding to calcium fluctuations in their environment.
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MESH Headings
- Antigens, CD/biosynthesis
- Antigens, CD/immunology
- B-Lymphocytes/enzymology
- B-Lymphocytes/immunology
- Calcineurin/immunology
- Calcineurin/metabolism
- Calcium/immunology
- Calcium/metabolism
- Calcium Signaling/immunology
- Humans
- Immunoglobulins/biosynthesis
- Immunoglobulins/immunology
- Lymphocyte Activation/immunology
- Membrane Glycoproteins/biosynthesis
- Membrane Glycoproteins/immunology
- NF-kappa B/immunology
- NF-kappa B/metabolism
- Phospholipase C gamma/immunology
- Phospholipase C gamma/metabolism
- Phosphotransferases/immunology
- Phosphotransferases/metabolism
- Receptors, Antigen, B-Cell/immunology
- Receptors, Antigen, B-Cell/metabolism
- Receptors, Calcium-Sensing/antagonists & inhibitors
- Receptors, Calcium-Sensing/immunology
- Receptors, Calcium-Sensing/metabolism
- Receptors, Cytokine/agonists
- Receptors, Cytokine/immunology
- Receptors, Cytokine/metabolism
- Toll-Like Receptors/immunology
- Toll-Like Receptors/metabolism
- Transcription, Genetic/drug effects
- Transcription, Genetic/immunology
- CD83 Antigen
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Affiliation(s)
- Caitlin M Hammond
- Division of Molecular and Cellular Biology, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
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