scholarly journals Photoperiod-dependent modulation of anti-Müllerian hormone in female Siberian hamsters, Phodopus sungorus

Reproduction ◽  
2008 ◽  
Vol 135 (3) ◽  
pp. 335-342 ◽  
Author(s):  
Esther W Kabithe ◽  
Ned J Place
Keyword(s):  
Granulosa Cells ◽  
Expression Patterns ◽  
Follicular Development ◽  
Day Length ◽  
Phodopus Sungorus ◽  
Reproductive Aging ◽  
Primordial Follicles ◽  
Short Day ◽  
Siberian Hamsters ◽  
Secondary Stage

Fertility and fecundity decline with advancing age in female mammals, but reproductive aging was decelerated in Siberian hamsters (Phodopus sungorus) raised in a short-day (SD) photoperiod. Litter success was significantly improved in older hamsters when reared in SD and the number of primordial follicles was twice that of females held in long days (LD). Because anti-Müllerian hormone (AMH) appears to inhibit the recruitment of primordial follicles in mice, we sought to determine whether the expression patterns of AMH differ in the ovaries and serum of hamsters raised in SD versus LD. Ovaries of SD female hamsters are characterized by a paucity of follicular development beyond the secondary stage and are endowed with an abundance of large eosinophilic cells, which may derive from granulosa cells of oocyte-depleted follicles. In ovaries from 10-week-old SD hamsters, we found that the so-called ‘hypertrophied granulosa cells’ were immunoreactive for AMH, as were granulosa cells within healthy-appearing primary and secondary follicles. Conversely, ovaries from age-matched LD animals lack the highly eosinophilic cells present in SD ovaries. Therefore, AMH staining in LD was limited to primary and secondary follicles that are comparable in number to those found in SD ovaries. The substantially greater AMH expression in SD ovaries probably reflects the abundance of hypertrophied granulosa cells in SD ovaries and their relative absence in LD ovaries. The modulation of ovarian AMH by day length is a strong mechanistic candidate for the preservation of primordial follicles in female hamsters raised in a SD photoperiod.

509. REGULATING MURINE FOLLICLE DEVELOPMENT BY STIMULATION OF THE JAK2/STAT3 SIGNAL TRANSDUCTION PATHWAY

2009 ◽  
Vol 21 (9) ◽  
pp. 108
Author(s):  
R. A. Keightley ◽  
B. Nixon ◽  
S. D. Roman ◽  
D. L. Russell ◽  
R. L. Robker ◽  
...  
Keyword(s):  
Significant Role ◽  
Granulosa Cells ◽  
Ovarian Follicle ◽  
Expression Patterns ◽  
Follicular Development ◽  
Janus Kinase ◽  
Follicle Development ◽  
Mrna Levels ◽  
Primordial Follicles ◽  
Stat3 Signalling

Follicular development requires the recruitment of primordial follicles into the growing follicle pool following initiation of multiple cytokine signalling pathways. Suppression of follicular development is thought to be key to maintaining the population of primordial follicles and allowing for controlled release of these follicles throughout the reproductive lifespan of the female. However, little is known of the processes and signalling molecules that suppress primordial follicle activation and early follicle growth. Our group has identified significant upregulation of the Janus Kinase 2 (JAK2)/ Signal Transducer and Activator of Transcription 3 (STAT3) signalling pathway inhibitor the Suppressor of Cytokine Signalling 4 (SOCS4) that coincides with the initial wave of follicular activation in theneonatal mouse ovary. Further studies by our group have localised the SOCS4 protein to the granulosa cells of activating and growing follicles, suggesting SOCS4 expression may be linked to follicular activation. We have focused on examining protein localisation and gene expression patterns of the eight SOCS family members CIS and SOCS1-7. We have recently demonstrated that co-culture of neonatal ovaries with Kit Ligand (KL) for 2 days increases the mRNA levels of all SOCS genes. We also demonstrated the co-localisation of SOCS2 proteins with the KL receptor c-kit in the mural granulosa cells of antral, and large pre-antral follicles suggesting a significant role for SOCS2 in the later stages of follicular development. We have also shown that culturing ovaries with the potent JAK2 inhibitor AG490 substantially reduces mRNA levels of all SOCS and STAT genes that we have so far measured. We hypothesise a significant role for JAK2/STAT3 signalling in promoting the activation and early growth of ovarian follicles. Our investigations have identified significant roles for JAK2/STAT3 and the SOCS family in the regulation of ovarian follicle development.

scholarly journals Kisspeptin level in the aging ovary is regulated by the sympathetic nervous system

2017 ◽  
Vol 232 (1) ◽  
pp. 97-105 ◽  
Author(s):  
Daniela Fernandois ◽  
Gonzalo Cruz ◽  
Eun Kyung Na ◽  
Hernán E Lara ◽  
Alfonso H Paredes
Keyword(s):  
Adrenergic Receptor ◽  
Follicular Development ◽  
Sympathetic Nerves ◽  
Female Rats ◽  
Reproductive Aging ◽  
Beta Adrenergic Receptor ◽  
Beta Adrenergic ◽  
Primordial Follicles ◽  
Follicular Cyst

Previous work has demonstrated that the increase in the activity of sympathetic nerves, which occurs during the subfertility period in female rats, causes an increase in follicular cyst development and impairs follicular development. In addition, the increase in ovarian sympathetic activity of aged rats correlates with an increased expression of kisspeptin (KISS1) in the ovary. This increase in KISS1 could participate in the decrease in follicular development that occurs during the subfertility period. We aimed to determine whether the blockade of ovarian sympathetic tone prevents the increase in KISS1 expression during reproductive aging and improves follicular development. We performed 2 experiments in rats: (1) an in vivo blockade of beta-adrenergic receptor with propranolol (5.0 mg/kg) and (2) an ovarian surgical denervation to modulate the sympathetic system at these ages. We measured Kisspeptin and follicle-stimulating hormone receptor (FSHR) mRNA and protein levels by qRT-PCR and western blot and counted primordial, primary and secondary follicles at 8, 10 and 12 months of age. The results showed that ovarian KISS1 decreased but FSHR increased after both propranolol administration and the surgical denervation in rats of 8, 10 and 12 months of age. An increase in FSHR was related to an increase in the number of smaller secondary follicles and a decreased number of primordial follicles at 8, 10 and 12 months of age. These results suggest that intraovarian KISS1 is regulated by sympathetic nerves via a beta-adrenergic receptor and participates locally in ovarian follicular development in reproductive aging.

scholarly journals MicroRNA Mediating Networks in Granulosa Cells Associated with Ovarian Follicular Development

2017 ◽  
Vol 2017 ◽  
pp. 1-18 ◽  
Author(s):  
Baoyun Zhang ◽  
Long Chen ◽  
Guangde Feng ◽  
Wei Xiang ◽  
Ke Zhang ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Granulosa Cells ◽  
Messenger Rna ◽  
Expression Patterns ◽  
Follicular Development ◽  
Functional Networks ◽  
Signal Pathways ◽  
Differentially Expressed Mirnas ◽  
Selection Of

Ovaries, which provide a place for follicular development and oocyte maturation, are important organs in female mammals. Follicular development is complicated physiological progress mediated by various regulatory factors including microRNAs (miRNAs). To demonstrate the role of miRNAs in follicular development, this study analyzed the expression patterns of miRNAs in granulosa cells through investigating three previous datasets generated by Illumina miRNA deep sequencing. Furthermore, via bioinformatic analyses, we dissected the associated functional networks of the observed significant miRNAs, in terms of interacting with signal pathways and transcription factors. During the growth and selection of dominant follicles, 15 dysregulated miRNAs and 139 associated pathways were screened out. In comparison of different styles of follicles, 7 commonly abundant miRNAs and 195 pathways, as well as 10 differentially expressed miRNAs and 117 pathways in dominant follicles in comparison with subordinate follicles, were collected. Furthermore, SMAD2 was identified as a hub factor in regulating follicular development. The regulation of miR-26a/b onsmad2messenger RNA has been further testified by real time PCR. In conclusion, we established functional networks which play critical roles in follicular development including pivotal miRNAs, pathways, and transcription factors, which contributed to the further investigation about miRNAs associated with mammalian follicular development.

scholarly journals Pentachloronitrobenzene alters progesterone production and primordial follicle recruitment in cultured granulosa cells and rat ovary†

2019 ◽  
Vol 102 (2) ◽  
pp. 511-520
Author(s):  
Yanrong Kuai ◽  
Xiaobo Gao ◽  
Huixia Yang ◽  
Haiyan Luo ◽  
Yang Xu ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Granulosa Cells ◽  
Crop Production ◽  
Follicular Development ◽  
Mitogen Activated Protein Kinase ◽  
Dependent Manner ◽  
Serum Progesterone ◽  
Primordial Follicles ◽  
Progesterone Production

Abstract Pentachloronitrobenzene (PCNB) is an organochlorine fungicide widely used for crop production and has become an environmental concern. Little is known about the effect of PCNB on ovarian steroidogenesis and follicular development. We found that PCNB stimulated Star expression and progesterone production in cultured rat granulosa cells in a dose-dependent manner. PCNB activated mitogen-activated protein kinase (MAPK3/1) extracellulat regulated kinase (ERK1/2), thus inhibition of either protein kinase A (PKA) or MAPK3/1 signaling pathway significantly attenuated progesterone biosynthesis caused by PCNB, suggesting that PCNB induced progesterone production by activating the cyclic adenosine monophosphate (cAMP/PKA) and MAPK3/1 signaling pathways. Further investigation demonstrated that PCNB induced Star expression and altered MAPK3/1 signaling in ovary tissues of immature SD rats treated with PCNB at the dose of 100, 200, or 300 mg/kg by daily gavage for 7 days, while serum progesterone level was dose-dependently decreased. We demonstrated that PCNB exposure accelerated the recruitment of primordial follicles into the growing follicle pool in ovary tissues, accompanied by increased levels of anti-Mullerian hormone (AMH) in both ovary tissues and serum. Taken together, our data demonstrate for the first time that PCNB stimulated Star expression, altered MAPK3/1 signaling and progesterone production in vivo and in vitro, and accelerated follicular development with a concomitant increase in AMH in ovary tissues and serum. Our findings provide novel insight into the toxicity of PCNB to animal ovary function.

Expression profiling of primary cultured buffalo granulosa cells from different follicular size in comparison with their in vivo counterpart

Zygote ◽  
2020 ◽  
Vol 28 (3) ◽  
pp. 233-240
Author(s):  
Ahmed S.A. Sosa ◽  
Sally Ibrahim ◽  
Karima Gh. M. Mahmoud ◽  
Mohamed M. Ayoub ◽  
Mohamed S.S. Abdo ◽  
...  
Keyword(s):  
Relative Abundance ◽  
Granulosa Cells ◽  
Expression Patterns ◽  
Marker Gene ◽  
Follicular Development ◽  
Nuclear Antigen ◽  
Enzyme Linked Immunosorbent Assay ◽  
Suitable Model ◽  
Follicular Size

SummaryThis study aimed to: (i) characterize cultured granulosa cells (GCs) from different follicle sizes morphologically and molecularly; and (ii) select a suitable model according to follicular size that maintained GC function during culture. Buffalo ovaries were collected from a slaughterhouse and follicles were classified morphologically into: first group ≤ 4 mm, second group 5–8 mm, third group 9–15 mm and fourth group 16–20 mm diameter. GC pellets were divided into two portions. The first portion served as the control fresh pellet, and the secondwas used for 1 week for GC culture. Total RNA was isolated, and qRT-PCR was performed to test for follicle-stimulating hormone receptor (FSHR), cytochrome P450 19 (CYP19), luteinizing hormone/choriogonadotropin receptor (LHCGR), proliferating cell nuclear antigen (PCNA), apoptosis-related cysteine peptidase (CASP3), anti-Müllerian hormone (AMH), and phospholipase A2 group III (PLA2G3) mRNAs. Estradiol (E2) and progesterone (P4) levels in the culture supernatant and in follicular fluids were measured using enzyme-linked immunosorbent assay (ELISA). Basic DMEM-F12 medium maintained the morphological appearance of cultured GCs. The relative abundance of FSHR, CYP19, and LHCGR mRNAs was 0.001 ≤ P ≤ 0.01 and decreased at the end of culture compared with the fresh pellet. There was a fine balance between expression patterns of the proliferation marker gene (PCNA) and the proapoptotic marker gene (CASP3). AMH mRNA was significantly increased (P < 0.001) in cultured GCs from small follicles, while cultured GCs from other three categories (5–8 mm, 9–15 mm and 16–20 mm) showed a clear reduction (P < 0.001). Interestingly, the relative abundance of PLA2G3 mRNA was significantly (P < 0.001) increased in all cultured GCs. E2 and P4 concentrations were significantly (P < 0.001) decreased in all cultured groups. Primary cultured GCs from small follicles could be a good model for better understanding follicular development in Egyptian buffaloes.

Perinatal photoperiod organizes adult immune responses in Siberian hamsters (Phodopus sungorus)

2006 ◽  
Vol 290 (6) ◽  
pp. R1714-R1719 ◽  
Author(s):  
Zachary M. Weil ◽  
Leah M. Pyter ◽  
Lynn B. Martin ◽  
Randy J. Nelson
Keyword(s):  
Immune System ◽  
Immune Function ◽  
Breeding Season ◽  
Somatic Growth ◽  
Developmental Trajectory ◽  
Day Length ◽  
Phodopus Sungorus ◽  
Siberian Hamsters ◽  
Time Of Year ◽  
Induced Changes

Individuals of many nontropical rodent species display reproductive, immunological, and somatic responses to day length. In general, short day (SD) lengths inhibit reproduction and enhance immune function in the laboratory when all other conditions are held constant. Most studies to date have focused on seasonal variation in immune function in adulthood. However, perinatal photoperiods also communicate critical day length information and serve to establish a developmental trajectory appropriate for the time of year. Nontropical rodents born early in the breeding season undergo rapid reproductive development, presumably to promote mating success during their first reproductive season. Rodents born late in the breeding season suspend somatic growth and puberty until the following vernal breeding season. We tested the hypothesis that perinatal day lengths have similar enduring effects on the immune system of rodents. Siberian hamsters ( Phodopus sungorus) were maintained prenatally and until weaning (21 days) in either SDs (8 h light:16 h dark) or long days (LD) (16 h light:8 h dark), then they were weaned into either the opposite photoperiod or maintained in their natal photoperiod, forming four groups (LD-LD, LD-SD, SD-LD, and SD-SD). After 8-wk in these conditions, cell-mediated immune activity was compared among groups. SD-SD hamsters of both sexes enhanced immune function relative to all other groups. The reproductive effects of perinatal photoperiod were not evident by the end of the experiment; circulating testosterone and cortisol sampled at the end of the experiment reflected the postweaning, but not the perinatal photoperiod. This experiment demonstrates long-lasting organizational effects of perinatal photoperiod on the rodent immune system and indicates that photoperiod-induced changes in the immune system are dissociable from changes in the reproductive system.

Follistatin but not α or βA inhibin subunit mRNA is expressed in ovine fetal ovaries in late gestation

1994 ◽  
Vol 13 (1) ◽  
pp. 1-9 ◽  
Author(s):  
R Braw-Tal ◽  
D J Tisdall ◽  
N L Hudson ◽  
P Smith ◽  
K P McNatty
Keyword(s):  
Mrna Expression ◽  
Granulosa Cells ◽  
Cell Function ◽  
Follicular Development ◽  
Primordial Follicle ◽  
Late Gestation ◽  
Follicle Growth ◽  
Primordial Follicles ◽  
Fetal Ovary ◽  
Ovine Fetal

ABSTRACT The aim of this study was to investigate the sites of follistatin and α and βA inhibin mRNA expression in the ovaries of female sheep fetuses at 90, 100, 120 and 135 days of gestation (term=day 147). At 90 and 100 days primordial follicles were formed, followed by the appearance of primary follicles at 100 days of gestation. At days 120 and 135, primordial, primary and preantral (i.e. secondary) follicles were present in the ovaries, but antral (i.e. tertiary) follicles were not observed at any of these gestational ages. Two Booroola genotypes were studied: homozygous carriers (BB) and non-carriers (++) of the fecundity gene (FecB). Irrespective of genotype no specific hybridization of the α and βA inhibin riboprobes was detected in any ovarian cells at days 90, 100, 120 or 135 of gestation. In control mature ovaries, on the other hand, strong hybridization in the granulosa cells of antral follicles was observed. In contrast to α and βA inhibin, follistatin antisense (but not sense) riboprobes hybridized specifically to the granulosa cells of preantral follicles with two or more layers of cells at days 120 and 135 of gestation. Moreover, hybridization was also evident in the cells of the ovarian rete at days 120 and 135, but not at 90 or 100 days. No follistatin mRNA expression was observed in the granulosa cells of primordial or primary follicles or in any other ovarian cell type at any of the gestational ages examined. No FecB-specific differences in follistatin expression were noted with respect to stage of preantral follicular development and there were no obvious differences in the intensity of expression. These results show that follistatin mRNA is expressed specifically in the granulosa cells and intraovarian rete. Expression of follistatin in rete cells was coincident with the increasing numbers of growing follicles within the fetal ovary, indicating that rete cell function may have a role in the ontogeny of early follicular growth. Our results suggest that follistatin and α and βA inhibin may not be important for the initiation of follicle growth in the sheep ovary, since these genes are not expressed during the transformation of a primordial follicle to a primary structure. However, the evidence for follistatin mRNA expression in the ovine fetal ovary implies that this hormone is likely to play a role during the early stages of follicle growth.

scholarly journals Morphological classification of bovine ovarian follicles

Reproduction ◽  
2010 ◽  
Vol 139 (2) ◽  
pp. 309-318 ◽  
Author(s):  
R J Rodgers ◽  
H F Irving-Rodgers
Keyword(s):  
Basal Lamina ◽  
Granulosa Cells ◽  
Follicular Development ◽  
Basal Cells ◽  
Morphological Classification ◽  
Primordial Follicles ◽  
Antral Follicles ◽  
Different Types ◽  
Biological Differences

Follicle classification is an important aid to the understanding of follicular development and atresia. Some bovine primordial follicles have the classical primordial shape, but ellipsoidal shaped follicles with some cuboidal granulosa cells at the poles are far more common. Preantral follicles have one of two basal lamina phenotypes, either a single aligned layer or one with additional layers. In antral follicles <5 mm diameter, half of the healthy follicles have columnar shaped basal granulosa cells and additional layers of basal lamina, which appear as loops in cross section (‘loopy’). The remainder have aligned single-layered follicular basal laminas with rounded basal cells, and contain better quality oocytes than the loopy/columnar follicles. In sizes >5 mm, only aligned/rounded phenotypes are present. Dominant and subordinate follicles can be identified by ultrasound and/or histological examination of pairs of ovaries. Atretic follicles <5 mm are either basal atretic or antral atretic, named on the basis of the location in the membrana granulosa where cells die first. Basal atretic follicles have considerable biological differences to antral atretic follicles. In follicles >5 mm, only antral atresia is observed. The concentrations of follicular fluid steroid hormones can be used to classify atresia and distinguish some of the different types of atresia; however, this method is unlikely to identify follicles early in atresia, and hence misclassify them as healthy. Other biochemical and histological methods can be used, but since cell death is a part of normal homoeostatis, deciding when a follicle has entered atresia remains somewhat subjective.

scholarly journals MT1 Melatonin Receptors Mediate Somatic, Behavioral, and Reproductive Neuroendocrine Responses to Photoperiod and Melatonin in Siberian Hamsters (Phodopus sungorus)

Endocrinology ◽  
2010 ◽  
Vol 151 (2) ◽  
pp. 714-721 ◽  
Author(s):  
Brian J. Prendergast
Keyword(s):  
Reproductive Function ◽  
Melatonin Receptors ◽  
Day Length ◽  
Phodopus Sungorus ◽  
Receptor Subtypes ◽  
Gonadotropin Secretion ◽  
Siberian Hamsters ◽  
The Central Nervous System ◽  
Necessary And Sufficient ◽  
And Behavior

Environmental day length drives nocturnal pineal melatonin secretion, which in turn generates or entrains seasonal cycles of physiology, reproduction, and behavior. In mammals, melatonin (MEL) binds to a number of receptor subtypes including high-affinity (MT1 and MT2) and low-affinity (MT3, nuclear orphan receptors) binding sites, which are distributed throughout the central nervous system and periphery. The MEL receptors that mediate photoperiodic reproductive and behavioral responses to MEL have not been identified in a reproductively photoperiodic species. Here I tested the hypothesis that MT1 receptors are necessary and sufficient to engage photoperiodic responses by challenging male Siberian hamsters (Phodopus sungorus), a species that does not express functional MT2 receptors, with ramelteon (RAM), a specific MT1/MT2 receptor agonist. In hamsters housed in a long-day photoperiod, late-afternoon RAM treatment inhibited gonadotropin secretion, induced gonadal regression, and suppressed food intake and body mass, mimicking effects of MEL. In addition, chronic (24 h/d) RAM infusions were sufficient to obscure endogenous MEL signaling, and these treatments attenuated gonadal regression in short days. Together, the outcomes indicate that signaling at the MT1 receptor is sufficient and necessary to mediate the effects of photoperiod-driven changes in MEL on behavior and reproductive function in a reproductively photoperiodic mammal.

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