Progesterone receptors and proliferating cell nuclear antigen expression in equine luteal tissue

Steroid hormones act via specific receptors, and these play an important physiological role in the ovary. The objective of this study was to evaluate the cellular distribution of progesterone receptors and their staining intensity in different equine luteal structures during the breeding season, as well as their relationship to luteal cell composition, cell proliferation pattern and plasma progesterone (P4) concentration. There was an increase in proliferating cell nuclear antigen (PCNA) expression in large luteal cells from the corpus hemorrhagicum (CH) to mid-luteal phase, followed by a decrease toward the late luteal stage. In the CH, the number of large luteal cells was lower than in other structures. Only large luteal cells showed positive staining for P4 receptors. An increase in staining intensity for P4 receptors was observed between CH and mid-phase corpus luteum, and CH and late-phase corpus luteum. Synthesis of P4 started at a very early stage of the luteal structure and was accompanied by an increase in P4 receptors and PCNA expression, and proliferation of large luteal cells, until mid-luteal phase. These data suggest that large luteal cells might play an important role in the regulation or synthesis of P4 in equine luteal structures.

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Cell Proliferation as Assessed by Expression of Proliferating Cell Nuclear Antigen or the Uptake of Bromodeoxyuridine in a Rabbit Model of Leg-lengthening

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.1055/s-0038-1632511 ◽

1996 ◽

Vol 09 (03) ◽

pp. 95-100 ◽

Cited By ~ 2

Author(s):

G. Li ◽

A. H. R. W. Simpson ◽

J. Kenwright ◽

J. T. Triffitt

Keyword(s):

Cell Proliferation ◽

Proliferating Cell Nuclear Antigen ◽

Rabbit Model ◽

Experimental System ◽

Nuclear Antigen ◽

Positive Staining ◽

Leg Lengthening ◽

Staining Index ◽

Proliferating Cell ◽

Distraction Rate

SummaryAn experimental model of leg lengthening has been used to study the cellular responses of the regenerating bone to different rates of distraction. Cell proliferation were assessed by detection of proliferating cell nuclear antigen using a monoclonal antibody, PC10. The technique was verified by comparison with bromodeoxyuridine uptake and subsequent detection with specific antibody (Bu20A). The positive staining index (PSI) was calculated for a variety of tissues and the PC10 PSI was greater than that of Bu20A, as described by the expression: PC10 PSI = 1.6 Bu20A PSI + 12.9, with a correlation coefficient 0.79. The results suggest that PC10 may be used as an alternative marker to assess cell proliferation in rabbit regenerating bone tissue. In addition, the rate of cell proliferation during leg-lengthening was found to reach a maximum at a distraction rate of 0.7 mm/day without further change at higher rates.Cell proliferation was assessed in an experimental system of leg-lengthening by two separate methods. The presence of proliferating cell nuclear antigen or the uptake of bromodeoxyuridine were determined immuno-histochemically. Both methods indicated cell proliferation during leg-lengthening reaches a maximum at a distraction rate of 0.7 mm/day.

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Proliferating cell nuclear antigen (PCNA) immunoreactivity in ovarian serous and mucinous neoplasms: diagnostic and prognostic value

International Journal of Gynecological Cancer ◽

10.1046/j.1525-1438.1993.03060391.x ◽

1993 ◽

Vol 3 (6) ◽

pp. 391-394 ◽

Cited By ~ 2

Author(s):

N. Wilkinson ◽

C. H. Buckley ◽

H. Fox ◽

R. J. Hale ◽

L. Chawner ◽

...

Keyword(s):

Proliferating Cell Nuclear Antigen ◽

Prognostic Value ◽

Malignant Tumors ◽

Nuclear Antigen ◽

Malignant Neoplasms ◽

Positive Staining ◽

Patient Death ◽

Mucinous Neoplasms ◽

Positive Immunoreactivity ◽

Proliferating Cell

Sixty-two serous and mucinous ovarian tumors, an admixture of benign, borderline and malignant neoplasms, were immunostained for proliferating cell nuclear antigen (PCNA), with the monoclonal antibody PC10. The PC10 index, the proportion of cells showing nuclear positive staining, was calculated in each case. All the tumors showed positive immunoreactivity for PCNA. There was no overlap of PC10 counts between benign, borderline and malignant serous tumors but within the mucinous group of neoplasms there was considerable overlap between the counts for borderline and malignant tumors. There was no relationship between the PC10 index and the surgical stage of the malignant neoplasms and the index could not be correlated with patient death. Staining for PCNA does not, therefore, appear to be of any prognostic value in ovarian adenocarcinomas.

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Expression and role of resistin on steroid secretion in the porcine corpus luteum

Reproduction ◽

10.1530/rep-21-0236 ◽

2021 ◽

Author(s):

Patrycja Kurowska ◽

Monika Sroka ◽

Monika Dawid ◽

Ewa Mlyczyńska ◽

Natalia Respekta ◽

...

Keyword(s):

Protein Kinase ◽

Corpus Luteum ◽

Luteal Phase ◽

Cell Function ◽

Orphan Receptor ◽

Mitogen Activated Protein Kinase ◽

Luteal Cell ◽

Steroid Synthesis ◽

Steroid Secretion ◽

Luteal Cells

Resistin plays an important role in adipogenesis, obesity, insulin resistance and reproduction. Previous studies showed resistin action on ovarian follicular cells; however, whether resistin regulates steroid secretion in luteal cells is still unknown. Our aim was first to determine the expression of resistin and its potential receptors (tyrosine kinase-like orphan receptor 1 [ROR1] and Toll-like receptor 4 [TLR4]) in the porcine corpus luteum (CL), regulation of its expression, effect on kinases phosphorylation and luteal steroidogenesis. Our results showed that the expression of resistin and its receptors was dependent on the luteal phase and this was at the mRNA level higher in the late compared with the early and middle luteal phase. At the opposite, resistin protein expression was higher in the middle and late compared with the early luteal phase, while ROR1 and TLR4 expression was highest in the early luteal phase. Additionally, we observed cytoplasmic localisation of resistin, ROR1 and TLR4 in small and large luteal cells. We found that luteinising hormone, progesterone (P4), insulin and insulin-like growth factor 1 regulated the protein level of resistin, ROR1 and TLR4. Resistin decreased P4 and increased oestradiol (E2) secretion via changing in steroidogenic enzymes expression and via the activation of protein kinase A (PKA) and mitogen-activated protein kinase (MAP3/1), increased the expression of receptors LHCGR and ESR2 and decreased the expression of PGR. Moreover, resistin decreased PKA phosphorylation and enhanced MAP3/1 phosphorylation. Taken together, resistin could act directly on steroid synthesis and serve as an important factor in in vivo luteal cell function.

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Proliferating cell nuclear antigen, estradiol and progesterone receptors as markers for different phases of rat estrous cycle

Steroids ◽

10.1016/s0039-128x(97)89557-8 ◽

1997 ◽

Vol 62 (11) ◽

pp. 747

Keyword(s):

Estrous Cycle ◽

Proliferating Cell Nuclear Antigen ◽

Progesterone Receptors ◽

Nuclear Antigen ◽

Proliferating Cell

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Expression of matrix metalloproteinases to induce the expression of genes associated with apoptosis during corpus luteum development in bovine

PeerJ ◽

10.7717/peerj.6344 ◽

2019 ◽

Vol 7 ◽

pp. e6344

Author(s):

Sang Hwan Kim ◽

Ji Hye Lee ◽

Jong Taek Yoon

Keyword(s):

Cell Death ◽

Matrix Metalloproteinases ◽

Corpus Luteum ◽

Luteal Phase ◽

Expression Patterns ◽

Basal Membrane ◽

Luteal Cell ◽

Luteal Cells ◽

Expression Of Genes ◽

Programed Cell Death

Here we investigated the expressions of apoptosis-associated genes known to induce programed cell death through mRNA expressions of two matrix metalloproteinases (MMPs) that are involved in the degradation of collagen and basal membrane in luteal cells cultured in the treatment media. Our results show that the activity of MMP-2 gelatinase was higher in the CL2 and CL1 of luteal phase, was gradually decreased in the CH2 and CH3 of luteal phase. In particular, the expressions of P4-r and survival-associated genes (IGFr, PI3K, AKT, and mTOR) were strongly induced during CL3 stage, whereas the levels of these genes in corpus luteum (CL) were lower during CL2 and CL1 stages. In the cultured lutein cells analyzed, we found that as MMPs increase, genes related to apoptosis (20α-hydroxy steroid dehydrogenase and caspase-3) also increase. In other words, the results for P4-r and survival-related gene expression patterns in the luteal cells were contrary to the MMPs activation results. These results indicate that active MMPs are differentially expressed to induce the expression of genes associated with programed cell death from the degrading luteal cells. Therefore, our results suggest that the MMPs activation may lead to luteal cell development or death.

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Localization of oxytocin and neurophysin in baboon (Papio anubis) corpus luteum by immunocytochemistry

Acta Endocrinologica ◽

10.1530/acta.0.1130570 ◽

1986 ◽

Vol 113 (4) ◽

pp. 570-575 ◽

Cited By ~ 15

Author(s):

Firyal S. Khan-Dawood

Keyword(s):

Corpus Luteum ◽

Rabbit Serum ◽

Corpora Lutea ◽

Positive Staining ◽

Normal Rabbit Serum ◽

Fallopian Tubes ◽

Papio Anubis ◽

Luteal Cells ◽

Luteal Tissue ◽

Immunocytochemical Reaction

Abstract. Immunoreactive oxytocin is detectable in the corpora lutea of women and cynomolgus monkeys by radioimmunoassay. To localize the presence of oxytocin and neurophysin I in ovarian tissues of subhuman primates, three corpora lutea and ovarian stromal tissues and two Fallopian tubes obtained during the menstrual cycle of the baboon and decidua from two pregnant baboons were examined using highly specific antisera against either oxytocin or neurophysin I and preoxidase-antiperoxidase light microscopy immunohistochemistry. Oxytocin-like as well as neurophysin I-like immunoreactivities were found in some cells of all the corpora lutea only, but could not be demonstrated in ovarian stromal tissues, Fallopian tubes and decidua. Specificity of the immunocytochemical reaction was further confirmed by immunoabsorption of the antiserum with excess oxytocin or neurophysin, after which the immunoreactivities for both oxytocin and neurophysin in the luteal tissue were negative. Similar controls using normal rabbit serum gave no positive staining for either oxytocin or neurophysin. Counterstaining of the positive immunoreactivities for oxytocin and neurophysin I with Mayer's haematoxylin and eosin demonstrated clearly that the oxytocin and neurophysin I appeared as granular material mainly within the cytoplasm of the luteal cells. The localization of immunoreactive oxytocin and neurophysin I in the corpus luteum of the baboon demonstrates directly the presence of these two neurohypophysial peptides within primate luteal cells and suggests their local production.

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