scholarly journals Kisspeptin is involved in ovarian follicular development during aging in rats

2015 ◽  
Vol 228 (3) ◽  
pp. 161-170 ◽  
Author(s):  
D Fernandois ◽  
E Na ◽  
F Cuevas ◽  
G Cruz ◽  
H E Lara ◽  
...  

We have previously reported that kisspeptin (KP) may be under the control of the sympathetic innervation of the ovary. Considering that the sympathetic activity of the ovary increases with aging, it is possible that ovarian KP also increases during this period and participates in follicular development. To evaluate this possibility, we determined ovarian KP expression and its action on follicular development during reproductive aging in rats. We measured ovarian KP mRNA and protein levels in 6-, 8-, 10- and 12-month-old rats. To evaluate follicular developmental changes, intraovarian administration of KP or its antagonist, peptide 234 (P234), was performed using a mini-osmotic pump, and to evaluate FSH receptor (FSHR) changes in the senescent ovary, we stimulated cultured ovaries with KP, P234 and isoproterenol (ISO). Our results shows that KP expression in the ovary was increased in 10- and 12-month-old rats compared with 6-month-old rats, and this increase in KP was strongly correlated with the increase in ovarian norepinephrine observed with aging. The administration of KP produced an increase in corpora lutea and type III follicles in 6- and 10-month-old rats, which was reversed by P234 administration at 10 months. In addition, KP decreased the number and size of antral follicles in 6- and 10-month-old rats, while P234 administration produced an increase in these structures at the same ages. In ovarian cultures KP prevented the induction of FSHR by ISO. These results suggest that intraovarian KP negatively participates in the acquisition of FSHR, indicating a local role in the regulation of follicular development and ovulation during reproductive aging.

Reproduction ◽  
2002 ◽  
pp. 143-153 ◽  
Author(s):  
D Mattiske ◽  
G Shaw ◽  
JM Shaw

Ovaries from a marsupial, the tammar wallaby (Macropus eugenii), were grafted into a eutherian recipient at known stages of development to ascertain whether normal development would occur. Xenografted ovaries from pouch young < 20 days old, before the onset of meiosis, retained few germ cells and developed tubule-like structures reminiscent of seminiferous cords. Ovaries from 50-day-old pouch young, which contain primordial follicles, developed into antral follicles and corpora lutea within the eutherian host, and produced hormones that stimulated the reproductive tract of the host. The timing of onset of antrum formation and the progress of follicle development were advanced relative to the timing of events in ovaries in situ. Frozen-thawed ovaries from 50-day-old donors developed into preantral follicles, but at a reduced rate and number. This finding shows that gonads of a marsupial species can develop as xenografts in a eutherian, forming large antral follicles. Accelerated follicular development in xenografts provides a potentially valuable model for studying the factors that control follicle development. Assisted reproduction of endangered marsupials may also be feasible using follicles from pouch young grown as xenografts in a eutherian host.


2003 ◽  
Vol 179 (2) ◽  
pp. 195-203 ◽  
Author(s):  
F Shi ◽  
PS LaPolt

FoxO1 is a transcription factor implicated in a growing number of physiological processes, including apoptosis, cell cycle progression, and insulin signaling. Recent findings indicate that FSH and growth factors influence ovarian functions in part through regulation of FoxO1. The present study utilized immunohistochemical analysis to determine the ovarian localization and regulation of FoxO1 protein levels in neonatal rats, immature rats during gonadotropin-induced follicular development, ovulation, and luteinization, and in spontaneously developing ovarian cysts of aging rats. In postnatal rats, FoxO1 immunoreactivity was very faint in ovaries of 5- and 10-day-old females. In contrast, strong immunoreactivity was observed in granulosa cells of larger developing follicles at 25 days of age. To stimulate follicle development, immature female rats received equine chorionic gonadotropin (eCG) followed 52 h later by an ovulatory dose of human chorionic gonadotropin (hCG). Prior to gonadotropin treatment, moderate FoxO1 immunoreactivity was observed in granulosa cells of small follicles. Subsequently, treatment with eCG markedly decreased FoxO1 protein levels in granulosa cells of healthy antral and preovulatory follicles. Interestingly, FoxO1 staining was observed in cumulus and antral, but not mural granulosa cells of preovulatory follicles. Induction of ovulation and luteinization with hCG further decreased ovarian FoxO1 levels, with no staining evident in corpora lutea. At all time points, the most intensive FoxO1 staining was observed in granulosa cells of atretic follicles, with predominantly nuclear localization. Similarly, while FoxO1 levels were low in granulosa cells of preovulatory follicles in proestrous rats, FoxO1 staining was intense in granulosa cells of spontaneously developing cystic follicles in aged, acyclic females. Together, these findings indicate that FoxO1 is expressed in a regulated, cell-specific manner during ovarian follicular development, atresia and luteinization, suggesting roles in these physiological processes.


1996 ◽  
Vol 134 (5) ◽  
pp. 649-654 ◽  
Author(s):  
Grietje Dijkstra ◽  
Dirk G de Rooij ◽  
Frank H de Jong ◽  
Robert van den Hurk

Dijkstra G, de Rooij DG, de Jong FH, van den Hurk R. Effect of hypothyroidism on ovarian follicular development, granulosa cell proliferation and peripheral hormone levels in the prepubertal rat. Eur J Endocrinol 1996;134:649–54. ISSN 0804–4643 The aim of this study was to examine the effects of prepubertal hypothyroidism on ovarian development in rats. Therefore, from birth up to day 40 postpartum, rats were given 6-propyl-2-thiouracil (PTU) via the drinking water of mothers and pups. At ages ranging from 12 to 40 days, ovarian weights were measured and serum was collected to estimate thyrotrophin (TSH), folliclestimulating hormone (FSH) and inhibin levels. Two hours before sacrifice the animals received an injection of bromodeoxyuridine (BrdU) to estimate the proliferative activity of the follicular granulosa cells. Ovaries were fixed in Carnoy's fluid and follicle counts were performed on sections stained with anti-BrdU and with haematoxylin and eosin. The PTU treatment resulted in increased serum TSH levels, indicative of hypothyroidism, and markedly lower body and ovarian weights, whereas serum FSH and inhibin levels were hardly affected. At day 40, ovaries of PTU-treated animals contained relatively more secondary and less antral follicles, smaller non-atretic antral follicles and more atretic follicles when compared with untreated rats, while corpora lutea were absent. It is concluded that this disturbed folliculogenesis is due to inadequate thyroid hormone supply, which hampers the differentiation and not the proliferation of granulosa cells because diameters of antral follicles were significantly smaller whereas the BrdU-labelling index had not changed. Robert van den Hurk, Department of Functional Morphology, Faculty of Veterinary Medicine, PO Box 80.157, 3508 TD Utrecht, The Netherlands


2004 ◽  
Vol 16 (9) ◽  
pp. 220
Author(s):  
R. L. Robker ◽  
W. V. Ingman ◽  
S. A. Robertson

Transforming Growth Factor β1 (TGFβ1) is essential for normal female reproduction. Mice with a targeted deletion in the TGFβ1 gene (TGFβ1–/–) have severely impaired fertility with pregnancy occurring in <25% of mated females. TGFβ1 is implicated in several aspects of ovarian function, including potentiation of granulosa cell proliferation and suppression of luteal cell apoptosis. Our initial observations indicate that estrous cycling is disrupted in TGFβ1–/– mice and that ovulation rate is reduced. To further investigate how impaired ovarian function contributes to the infertility of TGFβ1–/– mice, ovaries were isolated from TGFβ1+/+ and TGFβ1–/– littermates at proestrus and fixed and sectioned for examination of follicle morphology and growth. BrdU labelling was performed to detect granulosa cell proliferation and blood samples were obtained for analysis of gonadotrophins and ovarian steroid hormones. Histological examination showed that ovaries from TGFβ1–/– mice were smaller than those of TGF–1+/+ mice, however large antral follicles were observed, indicating that TGFβ1 is not essential for granulosa cell proliferation. Compared to TGFβ1+/+ ovaries however, there were fewer antral follicles and only rare corpora lutea. Interestingly, in some cases there were large numbers of macrophages surrounding small follicles suggesting increased follicular atresia and/or altered macrophage activity in the TGFβ1–/– ovaries. Ovaries and serum were also isolated from females at d4 post-coital for assessment of corpora lutea morphology. TGFβ1–/– ovaries weighed less and had fewer corpora lutea than TGFβ1+/+ ovaries. TGFβ1–/– corpora lutea also contained increased numbers of apoptotic cells and infiltrating macrophages indicative of premature luteal regression. Circulating progesterone levels were reduced in TGFβ1–/– females, as was progesterone production per corpus luteum further indicating a functional defect in luteal maintenance. Cumulatively these observations show that TGFβ1 has essential roles in regulation of ovarian macrophage populations, in normal follicular development and in the generation, maintenance and steroidogenic function of corpora lutea.


Reproduction ◽  
2014 ◽  
Vol 148 (5) ◽  
pp. 507-517 ◽  
Author(s):  
Ela Lutwak ◽  
Christopher A Price ◽  
Sagit-Sela Abramovich ◽  
Shiri Rabinovitz ◽  
Irit Granot ◽  
...  

Similar expression to FGF (SEF or IL17RD), is a tumor suppressor and an inhibitor of growth factors as well as of pro-inflammatory cytokine signaling. In this study, we examined the regulation ofSefexpression by gonadotropins during ovarian folliculogenesis. In sexually immature mice,in situhybridization (ISH) localizedSefgene expression to early developing oocytes and granulosa cells (GC) but not to theca cells.Sefwas also expressed in mouse ovarian endothelial cells, in the fallopian tube epithelium as well as in adipose tissue venules. SEF protein expression, determined by immunohistochemistry (IHC), correlated well withSefmRNA expression in GC, while differential expression was noticed in oocytes. HighSefmRNA but undetectable SEF protein levels were observed in the oocytes of primary/secondary follicles, while an inverse correlation was found in the oocytes of preantral and small antral follicles.SefmRNA expression dropped after pregnant mare's serum gonadotropin (PMSG) administration, peaked at 6–8 h after human chorionic gonadotropin (hCG) treatment, and declined by 12 h after this treatment. ISH and IHC localized the changes to oocytes and mural GC following PMSG treatment, whereasSefexpression increased in mural GC and declined in granulosa–lutein cells upon hCG treatment. The ovarian expression ofSEFwas confirmed using human samples. ISH localizedSEFtranscripts to human GC of antral follicles but not to corpora lutea. Furthermore,SEFmRNA was detected in human GC recovered from preovulatory follicles. These results are the first to demonstrate Sef expression in a healthy ovary during folliculogenesis. Hormonal regulation of its expression suggests that Sef may be an important factor involved in intra-ovarian control mechanisms.


Zygote ◽  
2006 ◽  
Vol 14 (2) ◽  
pp. 107-117 ◽  
Author(s):  
José R.V. Silva ◽  
Robert van den Hurk ◽  
José R. Figueiredo

SummaryTo examine the possibility that epidermal growth factor (EGF) and its receptor (EGF-R) are expressed throughout folliculogenesis, we studied the presence and distribution of EGF and EGF-R in goat ovaries. Ovaries of goats were collected and either fixed in paraformaldehyde for immunohistochemical localization of proteins, or used for the isolation of follicles, luteal cells and ovarian surface epithelium to study mRNA expression for EGF and EGF-R, using the reverse transcriptase polymerase chain reaction. EGF protein and mRNA were found in primordial, primary and secondary follicles as well as in small and large antral follicles and in surface epithelium, but in corpora lutea only the protein could be detected. Antral follicles expressed EGF mRNA in oocyte, cumulus, mural granulosa and theca cells. For EGF-R, both protein and mRNA were present at all stages of follicular development and in all antral follicular compartments. EGF-R protein and mRNA were also found in corpora lutea and surface epithelium. It is concluded that EGF and its receptor are expressed in goat ovarian follicles at all stages of follicle development, in corpora lutea, and in ovarian surface epithelium.


1985 ◽  
Vol 108 (2) ◽  
pp. 273-276 ◽  
Author(s):  
G. Robinson ◽  
J. J. Evans ◽  
M. E. Forster

Abstract. Injection of oxytocin into normal adult cycling mice caused alterations in ovarian histology. Oxytocin was administered early on the day of pro-oestrus and it induced the appearance of large numbers of corpora lutea by late pro-oestrus, suggesting oxytocin stimulated ovulation. When mice were examined very early on the day of normal oestrus the ovarian population of follicles was different in the experimental group from that in the control mice, there being increased numbers of preantral and antral follicles in treated animals. As oxytocin can cause an alteration in the timing of follicular maturation and ovulation processes study of communications between the adenohypophysis and areas containing oxytocin might be important for understanding physiological details of ovulation. The relative times at which, for instance, antral follicle and corpora lutea populations increased suggested that oxytocin might have more than one activity which affects ovarian behaviour.


1995 ◽  
Vol 144 (1) ◽  
pp. 39-47 ◽  
Author(s):  
W A van Cappellen ◽  
H M A Meijs-Roelofs ◽  
P Kramer ◽  
E C M van Leeuwen ◽  
R de Leeuw ◽  
...  

Abstract The effects of a single injection of recombinant human FSH (rhFSH; Org32489) on ovulation rate and timing and on antral follicle growth were studied in adult 5-day cyclic rats. Rats injected at 1700 h on dioestrus-2 with a dose of 10 IU rhFSH showed, on average, no increase in ovulation rate on the day of expected oestrus. However, an additional, precocious ovulation resulting in a normal number of corpora lutea 13·3±0·4, n=6) was found to take place on the night after injection, i.e. dioestrus-3. No mating behaviour, as shown by the absence of vaginal plugs the next morning, was observed at this ovulation. Follicle counts showed a loss of large antral follicles due to ovulation and increased numbers of healthy small antral follicles at 17 and 41 h after injection, indicating a decrease of atresia of growing follicles as well as additional recruitment of new antral follicles. The endogenous serum FSH concentration on the subsequent day of oestrus (65 h after the rhFSH injection) as well as recruitment of small antral follicles were lower in the rhFSH-treated rats than in saline-treated controls. The ovulation at oestrus, 48 h after the precocious, rhFSH-induced ovulation showed large differences in the number of oocytes between the rats in one treatment group. Similar results in terms of immediate ovulation induction were obtained by using a highly purified human urinary FSH preparation (i.e. metrodin). Furthermore, the direct induction of ovulation by rhFSH or metrodin could not be prevented by the injection of an LHRH antagonist. It was concluded that rhFSH can induce acute ovulation in rats, and stimulates follicular development directly or indirectly through increased FSH levels after ovulation. It induces antral follicle growth and decreases early atresia in small antral follicles. Journal of Endocrinology (1995) 144, 39–47


Endocrinology ◽  
2014 ◽  
Vol 155 (5) ◽  
pp. 1931-1943 ◽  
Author(s):  
Kalyne Bertolin ◽  
Jan Gossen ◽  
Kristina Schoonjans ◽  
Bruce D. Murphy

In the ovary, the follicular granulosa cells express the nuclear receptor Nr5a2 (nuclear receptor subfamily 5 group A member 2), also known as liver receptor homolog-1, and after ovulation, Nr5a2 expression persists in the corpus luteum. Previous studies demonstrated that Nr5a2 is required for both ovulation and luteal steroid synthesis. Our objectives were to analyze the temporal sequence in the regulatory effects of Nr5a2 in the ovary, with focus on its contribution to luteal function. We developed a female mouse model of granulosa-specific targeted disruption from the formation of the antral follicles forward (genotype Nr5a2Cyp19−/−). Mice lacking Nr5a2 in granulosa cells of antral follicles are infertile. Although their cumulus cells undergo expansion after gonadotropin stimulation, ovulation is disrupted in those mice, at least in part, due to the down-regulation of the progesterone receptor (Pgr) gene. The depletion of Nr5a2 in antral follicles permits formation of luteal-like structures but not functional corpora lutea, as evidenced by reduced progesterone levels and failure to support pseudopregnancy. Progesterone synthesis is affected by depletion of Nr5a2 due to, among others, defects in the transport of cholesterol, evidenced by down-regulation of Scarb1, Ldlr, and Star. Comparison of this mouse line with the models in which Nr5a2 is depleted from the primary follicle forward (genotype Nr5a2Amhr2−/−) and after the ovulatory signal (genotype Nr5a2Pgr−/−) demonstrates that Nr5a2 differentially regulates female fertility across the trajectory of follicular development.


2019 ◽  
Vol 12 (2) ◽  
pp. 89
Author(s):  
Janeen H. Trembley ◽  
Betsy T. Kren ◽  
Md. J. Abedin ◽  
Daniel P. Shaughnessy ◽  
Yingming Li ◽  
...  

The prosurvival protein kinase CK2, androgen receptor (AR), and nuclear factor kappa B (NFκB) interact in the function of prostate cells, and there is evidence of crosstalk between these signals in the pathobiology of prostate cancer (PCa). As CK2 is elevated in PCa, and AR and NFκB are involved in the development and progression of prostate cancer, we investigated their interaction in benign and malignant prostate cells in the presence of altered CK2 expression. Our results show that elevation of CK2 levels caused increased levels of AR and NFκB p65 in prostate cells of different phenotypes. Analysis of TCGA PCa data indicated that AR and CK2α RNA expression are strongly correlated. Small molecule inhibition or molecular down-regulation of CK2 caused reduction in AR mRNA expression and protein levels in PCa cells and in orthotopic xenograft tumors by various pathways. Among these, regulation of AR protein stability plays a unifying role in CK2 maintenance of AR protein levels. Our results show induction of various endoplasmic reticulum stress signals after CK2 inhibition, which may play a role in the PCa cell death response. Of note, CK2 inhibition caused loss of cell viability in both parental and enzalutamide-resistant castrate-resistant PCa cells. The present work elucidates the specific link of CK2 to the pathogenesis of PCa in association with AR and NFκB expression; further, the observation that inhibition of CK2 can exert a growth inhibitory effect on therapy-resistant PCa cells emphasizes the potential utility of CK2 inhibition in patients who are on enzalutamide treatment for advanced cancer.


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