105 P75 Neuronal Cells and Fibers in the Bovine Ovary

2018 ◽  
Vol 30 (1) ◽  
pp. 192
Author(s):  
R. Carrasco ◽  
C. E. Leonardi ◽  
J. Singh ◽  
G. P. Adams

Neurotrophins are molecules involved in the development and survival of neurons and its cellular projections. Results of recent studies have implicated the local role of the high affinity neurotropin receptor, trkA, in bovine ovarian follicle selection and early luteogenesis (Carrasco et al. 2016 Reprod. Biol. Endocrinol. 14, 47), but innervation and neuropeptide control remains an unexplored aspect of ovarian function. P75 is the low-affinity receptor for all neurotrophins and is expressed in ovarian tissue. The objective of this study was to explore the distribution of P75 neurons and fibres within the ovary and to examine the relationship of these components with follicular development. The ovaries of cows (n = 5) were collected at the time of slaughter, 36 h after induced luteolysis (i.e. proestrus). The ovaries were fixed in 4% paraformaldehyde for 48 h, and samples from the ovarian hilus, medulla, and cortex (3 blocks per ovary) were cryo-sectioned (20–50 µm). Tissue sections were incubated for 48 h with a rabbit antibody against rat P75 or a mouse monoclonal antibody against neurofilament. Immunodetection was visualised by an amplification procedure with horseradish peroxidase using nickel DAB as a chromogen. Sections were counterstained with nuclear fast red for follicle identification. Immunoreactive cell bodies were counted in 10 to 20 fields (40×) per section, and data were expressed based on ovarian areas (cortex, medulla, or hilus) as an average count per 40× field per animal. Data among ovarian regions were compared by ANOVA; differences were considered significant when P < 0.05. Antral follicles ≤5 mm displayed strong immunoreactivity in the theca layer, without reaction in the granulosa cells. In contrast, preovulatory follicles were devoid of P75 immuno-reactivity in the theca layer. Oval P75 immunoreactive neuron-like cells were present in all ovarian areas studied. The neuronal nature of the P75 immunoreactive cells was confirmed by the presence of a similar pattern when adjacent sections were stained for neurofilaments, a protein characteristic of neurons. In the stroma of the ovarian cortex and medulla, neurons were present individually (scattered) rather than grouped; however, a dense network of neurons and fibres was detected immediately beneath the ovarian surface epithelium. No differences between the cortex, medulla, and hilus were found in the mean number of immunoreactive cells (10.6 ± 2.8, 14.4 ± 3.6 and 13.9 ± 2.0 cells/40× field, respectively). Immunoreactive neuron-like cells and fibres were in close proximity to blood vessels in the ovarian medulla. Corpora lutea were devoid of P75 immunoreactivity. In conclusion, results document the existence of a neuronal network in the bovine ovary, displaying an association with follicles at different stages of development. The abundance of neuronal components (i.e. neuron cell bodies and axons) in the ovarian stromal and surface epithelium implies a role of innervation (either extrinsic or intrinsic) in the control of ovarian follicular development and function. Research was supported by the Natural Sciences and Engineering Research Council of Canada.

2004 ◽  
Vol 16 (9) ◽  
pp. 279 ◽  
Author(s):  
D. L. Russell

Female infertility has been reported in two lines of mice with mutation of the Egr-1 gene. One underlying cause of this defect is deficient LH production by pituitary gonadotropes. However, Egr-1 is also acutely regulated by both FSH and LH in ovarian granulosa cells (1). A role for this transcription factor in regulating gonadotrophin responsive target genes and ovarian function is hypothesised. Indeed the LH-receptor is a proposed target of Egr-1 regulation, but this has not been investigated in detail in vivo and is difficult to reconcile with the pattern of Egr-1 expression. In this study, the role of Egr-1 within the ovarian follicle was investigated using exogenous gonadotropin replacement in Egr-1–/– mice . Adult Egr-1–/– female mice superovulated by sequential PMSG and hCG stimulation and mated with proven male breeders failed to produced offspring while 90% of heterozygous females got pregnant and produced litters (7.4 � 2.9 pups per litter) within 22 days of stimulation. Recovery of oocytes from oviducts of immature superovulated mice revealed a reduced ovulation rate in null females (6.3 � 3.8 oocytes) compared to their heterozygous (18.0 � 6.5) and WT (17.8 � 6.8) littermates. Gross morphology and histology of exogenously stimulated ovaries were indistinguishable from their heterozygous or WT counterparts. Surprisingly, no alteration was detectable in the mRNA expression of previously reported direct Egr-1 responsive genes, namely LH-receptor and membrane prostaglandin E synthase (mPGES). Nor were mRNA for two critical ovulatory genes with putative Egr-1 response elements, ADAMTS-1 or versican V1 altered. Temporal and spatial expression of genes involved in ovarian steroidogenesis, P450scc and Cyp17 and LH-receptor, were indistinguishable from normal littermates during exogenously controled follicular development. Combined observations of acute Egr-1 induction by gonadotropins, reduced ovulation and complete infertility suggest an important role for Egr-1 in ovarian function. However, genes identified as targets of Egr-1 regulation in other studies proved to be Egr-1 independent in this model. (1) Russell et al. (2003) Mol. Endo. 17, 520.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
A Volodarsky-Perel ◽  
M Zajicek ◽  
D Shai ◽  
H Raanani ◽  
N Gruber ◽  
...  

Abstract Study question What is the predictive value of ovarian reserve evaluation in patients with non-iatrogenic primary ovarian insufficiency (NIPOI) for follicle detection in ovarian tissue harvested for cryopreservation? Summary answer Ovarian tissue cryopreservation (OTCP) should be considered if patients present at least one of the following parameters: detectable AMH, FSH≤20mIU/ml, detection of ≥ 1 antral follicle. What is known already In pre-pubertal girls suffering from NIPOI, which majorly has a genetic etiology, fertility preservation using OTCP is commonly practiced. When OTCP was performed in an unselected group of children and adolescents with NIPOI, only 26% of them had follicles in ovarian tissue while 74% did not benefit from the surgery. The role of preoperative evaluation of anti-müllerian hormone (AMH) serum level, follicular stimulating hormone (FSH) serum level, and trans-abdominal ultrasound for the antral follicle count to predict the detection of primordial follicles in the harvested ovarian tissue is unclear. Study design, size, duration We conducted a retrospective analysis of all patients ≤ 18 years old who were referred for fertility preservation counseling due to NIPOI at a single tertiary hospital between 2010 and 2020. If initial evaluation suggested a diminished ovarian reserve and at least one positive parameter indicating a follicular activity (AMH &gt; 0.16ng/ml, FSH ≤ 20mIU/ml, detection of ≥ 1 antral follicle by transabdominal sonography), OTCP was offered. Patients with 46XY gonadal dysgenesis were excluded. Participants/materials, setting, methods OTCP was performed laparoscopically in all cases. A fresh sample of cortical tissue was fixed in buffered formaldehyde for histological analysis. The rest of the ovarian tissue was cut into small cuboidal slices 1–2 mm in thickness and cryopreserved. After the serial sections, the histological slides were evaluated for the presence of follicles by a certified pathologist. Follicles were counted and categorized as primordial, primary, and secondary. Main results and the role of chance During the study period, 39 patients with suspected NIPOI were referred to the fertility preservation center. Thirty-seven patients included in the study were diagnosed with Turner’s syndrome (n = 28), Galactosemia (n = 3), Blepharophimosis-Ptosis-Epicanthus Inversus syndrome (n = 1), and idiopathic NIPOI (n = 6). Of 28 patients with Turner’s syndrome, 6 had 45X monosomy, 15 had mosaicism and 7 had structural anomalies in X-chromosome. One patient with gonadal dysgenesis and one with the presence of Y-chromosome in 20% of somatic cells were excluded from the study. OTCP was conducted in 14 patients with at least one positive parameter suggesting ovarian function. No complications of the surgical procedure or the anesthesia were observed. Primordial follicles were found in all patients with two or three positive parameters (100%) and in three of six cases with one positive parameter (50%). In total, of the 14 patients who underwent OTCP with at least one positive parameter, 11 (79%) had primordial follicles at biopsy (mean 23.9, range 2–47). This study demonstrates a positive predictive value of 79% for the detection of primordial follicles in patients who had at least one positive parameter of ovarian reserve evaluation. If two or three parameters were positive, the positive predictive value increased to 100%. Limitations, reasons for caution This study did not examine the negative predictive value of our protocol as OTCP was not recommended in the absence of positive parameters. The future fertility potential of cryopreserved tissue in the population with NIPOI is unclear and should be discovered in further studies. Wider implications of the findings: We suggest the evaluation of ovarian reserve by antral follicles count, AMH, and FSH serum levels prior to OTCP in patients with NIPOI. By recommendation of OTCP only if ≥ 1 parameter suggesting the ovarian function is positive, unnecessary procedures can be avoided. Trial registration number Not applicable


2014 ◽  
Vol 53 (3) ◽  
pp. R103-R118 ◽  
Author(s):  
Annu Makker ◽  
Madhu Mati Goel ◽  
Abbas Ali Mahdi

Abnormalities in ovarian function, including defective oogenesis and folliculogenesis, represent a key female reproductive deficiency. Accumulating evidence in the literature has shown that the PI3K/PTEN/Akt and TSC/mTOR signaling pathways are critical regulators of ovarian function including quiescence, activation, and survival of primordial follicles, granulosa cell proliferation and differentiation, and meiotic maturation of oocytes. Dysregulation of these signaling pathways may contribute to infertility caused by impaired follicular development, intrafollicular oocyte development, and ovulation. This article reviews the current state of knowledge of the functional role of the PI3K/PTEN/Akt and TSC/mTOR pathways during mammalian oogenesis and folliculogenesis and their association with female infertility.


Reproduction ◽  
2001 ◽  
pp. 711-721 ◽  
Author(s):  
H Vermeirsch ◽  
P Simoens ◽  
M Coryn ◽  
W Van den Broeck

Androgens play an essential role as autocrine or paracrine agents in ovarian follicular growth, maturation and luteinization. The aim of this study was to describe the normal cellular distribution of androgen receptors in the canine ovary at different stages of the oestrous cycle. Samples of both ovaries were obtained from 34 dogs, including six pregnant animals and three that had just produced litters. Presence of androgen receptors was visualized by immunohistochemistry on paraffin wax sections using a polyclonal antibody. Nuclear staining for androgen receptors was observed in the surface epithelium, cortical tubules, rete ovarii, follicle cells, thecal cells, luteal cells, granulosa cell cords and ovarian stroma, indicating that androgens have important roles in ovarian function in bitches. In theca interna cells of tertiary follicles, androgen production seems to be more important than androgen receptivity, as immunostaining for androgen receptors in these cells was weak compared with that in other ovarian stromal cells. In primordial and primary follicles, the immunostaining for androgen receptors was rather weak, indicating that androgens are of minor importance in early preantral follicles. In follicle cells of larger preantral and antral follicles, the immunostaining for androgen receptors increased with the stage of the follicle. Corpora lutea expressed less immunostaining, which was not correlated with serum progesterone concentrations, although local actions of progesterone on androgen receptors in corpora lutea cannot be excluded. In general, few correlations were found between immunostaining for androgen receptors and serum sex steroid concentrations, indicating that other factors regulate androgen receptors in the canine ovary.


1992 ◽  
Vol 134 (1) ◽  
pp. 11-18 ◽  
Author(s):  
R. G. Glencross ◽  
E. C. L. Bleach ◽  
B. J. McLeod ◽  
A. J. Beard ◽  
P. G. Knight

ABSTRACT To study the effects of immunoneutralization of endogenous inhibin on gonadotrophin secretion and ovarian function, prepubertal heifers (n = 6) were actively immunized against a synthetic peptide replica of the N-terminal sequence of bovine inhibin α subunit bIα(1–29)Tyr30) coupled to ovalbumin. In contrast to ovalbumin-immunized controls (n=6), bIα(1–29)Tyr30-immunized heifers had detectable inhibin antibody titres (% binding to 125I-labelled bovine inhibin at 1:2000 dilution of plasma) of 17 ± 3% (s.e.m.) at puberty, rising to 31 ± 5% by the end of the study period 7 months later. Neither age (immunized: 295 ± 8 days; controls: 300 ± 5 days) nor body weight (immunized: 254 ± 13 kg; controls 251 ± 9 kg) at onset of puberty differed between groups. Although the difference did not reach statistical significance, mean plasma FSH concentrations recorded in inhibin-immunized heifers remained 35–40% higher than in controls throughout the 12-week period leading up to puberty (P = 0·14) and during nine successive oestrous cycles studied after puberty (P=0·10). Plasma LH concentrations did not differ between groups at any time during the study. Inhibin immunization had no effect on oestrous cycle length (immunized: 19·8±0·5 days; controls: 19·9±0·5 days). However, in comparison with controls, inhibinimmunized heifers had more medium sized (≥0·5 to <1 cm diameter) follicles during both the preovulatory (95%, P<0·001) and post-ovulatory (110%, P < 0·05 waves of follicular growth and more large (>1 cm diameter) follicles during the preovulatory wave (49%, P<0·05). In addition, the number of corpora lutea observed during the post-ovulatory phase of each cycle was significantly greater in the inhibin-immunized group (43%, P<0·01), as was the recorded incidence of cycles with multiple ovulations (19/56 in the inhibin-immunized group compared with 0/54 in controls; P<0·001). All six inhibinimmunized heifers had at least one cycle with multiple ovulation whereas none of the control heifers did so. These results support the conclusion that immunoneutralization of endogenous inhibin using a synthetic peptide-based vaccine can enhance ovarian follicular development and ovulation rate in heifers. Whether this ovarian response is dependent upon the expected increase in secretion of FSH remains to be established. Journal of Endocrinology (1992) 134, 11–18


2016 ◽  
Vol 28 (2) ◽  
pp. 197
Author(s):  
R. Carrasco ◽  
J. Singh ◽  
G. P. Adams

Classical studies established that the removal of one of the paired organs produces a compensatory effect on the remaining organ. In the bovine ovary this aspect has not been examined in detail. We took advantage of follicular and luteal profiles from a previous study to retrospectively examine the effects of ovariectomy before and after ovulation on follicular dynamics of the remaining ovary in cattle. To characterise the prevalence and distribution of tyrosine kinase receptor A in the bovine ovary, the original design involved unilateral ovariectomy of cows at different stages of the periovulatory period. For the purposes of the present study, we combined data into 2 groups, a preovulatory group (n = 6 cows) and a post-ovulatory group (n = 5 cows), to provide sufficient data for statistical interpretation. The cows were examined daily by transrectal ultrasonography to determine the ovarian status. For the preovulatory group, a luteolytic dose of prostaglandin was administered when the dominant follicle of the second follicular wave reached ≥10 mm, and the ovary containing the dominant follicle was removed within 48 h. For the post-ovulatory group, ovariectomy was performed on the ovary containing the newly formed corpus luteum between Days 2 to 6 (Day 0 = ovulation). Unilateral ovariectomy was performed by colpotomy under caudal epidural anaesthesia using a chain ecraseur. After ovariectomy, cows were examined daily by ultrasonography from ovariectomy to the completion of an interovulatory interval (period between 2 ovulations). Single-point data were compared between groups by t-test, and binomial data were compared between groups by Fisher’s exact test. Double ovulations were detected in 3/6 ovariectomized in the preovulatory period and 2/5 ovariectomized in the post-ovulatory period. The first ovulation after ovariectomy tended to occur earlier in the preovulatory group than in the post-ovulatory group (P = 0.08), which was attributed primarily to the development of oversized persistent dominant follicles (~20 mm in diameter for ≥7 days in absence of a corpora lutea) in 2 of 5 cows in the post-ovulatory ovariectomy group. The interovulatory interval after ovariectomy was shorter in the post-ovulatory group than in the preovulatory group (14.6 ± 0.3 v. 20.3 ± 0.6 days; P = 0.01). No distinct patterns were detected in follicular and luteal dynamics between the pre- and post-ovulatory ovariectomy groups. The number of follicles ≥3 mm detected by ultrasonography was greater in the post-ovulatory ovariectomy group than in the preovulatory group on Days 6, 7, 8, and 16 of the first interovulatory interval after ovariectomy. In conclusion, results of this retrospective study support the concept that follicular and luteal effects of removal of one ovary are influenced by the timing of ovariectomy relative to ovulation. A prospective study involving a comparison of ovarian dynamics of the same cows before and after unilateral ovariectomy will provide a better understanding of the disruption that take place and the mechanisms controlling it. Research was supported by the Natural Sciences and Engineering Research Council of Canada.


2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e17019-e17019
Author(s):  
Valeria Bandovkina ◽  
Elena Mikhaylovna Frantsiyants ◽  
Nailya Guskova ◽  
Tatiana Moiseenko ◽  
Marina Vovkochina ◽  
...  

e17019 Background: The purpose of the study was to analyze hormonal disorders in tissues of histologically unchanged ovaries of patients with cervical cancer infected with HPV/Chlamydia trachomatis. Methods: We studied levels of estrone (E1), estradiol (E2), free estriol (E3), free (fT) and total (T) testosterone, progesterone (P4), steroid-binding globulin (SBG) and prolactin (PRL) by the ELISA in intact ovaries of 25 patients aged 53.4±3.2 years with cervical cancer T1b-2aN0M0. HPV presence was determined by Е7 protein expression, Chlamydia trachomatis (Ch. tr.) – by IgG and IgА to Ch. tr. and antigen/DNA by ELISA and Real-time PCR. Tissues of intact ovaries obtained during hysterectomy from 22 non-infected women of similar age with endometrial cancer T1N0M0 were used as the control. Results: The data demonstrated a sharp decrease in E2 level by 9.3 times and increase in E1 by 2.3 times in intact ovaries of cervical cancer patients infected with HPV and Ch. tr., compared with the values in controls. Changes were noted in the balance between some estrogen fractions: E1 percentage increased by 5 times, E3 – by 2.4 times and E2 percentage decreased by 4 times. Androgenic status in intact ovaries in cervical cancer was characterized with increased levels of T (by 5.1 times) and fT (by 1.6 times). We noted an increase in SBG concentration by more than 3 times in response to the release of androgens registered in ovarian tissue, as well as significant (by 4.4 times) increase in PRL and decrease in P4 by 1.5 times compared with non-infected tissues. Estrogens to P4 ratio in co-infected patients reduced by 1.6 times, while the PRL to P4 ratio increased by 6.4 times, mainly due to disorders in hormone-producing ovarian function. Conclusions: The development of malignant process in the cervix in a combined HPV and Chlamydia trachomatis infection is accompanied by disorders of the endocrine status in tissues of intact ovaries and shows the undeniable role of consequences of HPV/Chlamydia trachomatis coinfection in this process.


Reproduction ◽  
2017 ◽  
Vol 153 (2) ◽  
pp. R59-R68 ◽  
Author(s):  
Gonzalo Cruz ◽  
Daniela Fernandois ◽  
Alfonso H Paredes

Successful reproduction is the result of a myriad interactions in which the ovary and the ovarian follicular reserve play a fundamental role. At present, women who delay maternity until after 30 years of age have a decreased fertility rate due to various causes, including damaged follicles and a reduction in the reserve pool of follicles. Therefore, the period just prior to menopause, also known as the subfertile period, is important. The possibility of modulating the follicular pool and the health of follicles during this period to improve fertility is worth exploring. We have developed an animal model to study the ovarian ageing process during this subfertile period to understand the mechanisms responsible for reproductive senescence. In the rat model, we have shown that the sympathetic nervous system participates in regulating the follicular development during ovarian ageing. This article reviews the existing evidence on the presence and functional role of sympathetic nerve activity in regulating the follicular development during ovarian ageing, with a focus on the subfertile period.Free Spanish abstract: A Spanish translation of this abstract is freely available athttp://www.reproduction-online.org/content/153/2/R59/suppl/DC1.


Endocrinology ◽  
2004 ◽  
Vol 145 (11) ◽  
pp. 5373-5383 ◽  
Author(s):  
Yasuhiro Kobayashi ◽  
Fermin Jimenez-Krassel ◽  
Qinglei Li ◽  
Jianbo Yao ◽  
Ruiping Huang ◽  
...  

Abstract We recently obtained evidence that cocaine- and amphetamine-regulated transcript (CART), a potent anorectic neuropeptide, is expressed in the bovine ovary. The objectives of this study were to characterize bovine ovarian CART and determine its localization, regulation, and regulatory role during follicular development. CART mRNA was detected in stroma of adult ovaries and in large follicles, but was undetectable in several peripheral tissues, fetal ovaries, and corpora lutea. Within the ovary, CART mRNA and peptide were localized to the granulosal layer of some, but not all, antral follicles, with low, but detectable, expression in oocytes and cumulus cells. CART mRNA was undetectable in granulosal cells of dominant ovulatory follicles collected before and after the preovulatory gonadotropin surge, but was detected in the granulosal layer of adjacent subordinate follicles. In addition, amounts of CART mRNA and follicular fluid concentrations of CART peptide were greater in subordinate follicles vs. dominant follicles of the first follicular wave. Furthermore, CART treatment inhibited basal estradiol production, but not progesterone production, by granulosal cells in a dose-dependent fashion, and the effect was dependent on stage of cell differentiation. We conclude that granulosal cell CART expression is temporally regulated and potentially associated with follicle health status, and CART can inhibit granulosal cell estradiol production. Thus, CART may be a novel local regulator of follicular atresia in the bovine ovary.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jihyun Kim ◽  
Sooseong You

AbstractSamul-tang (SM), a traditional herbal medicine, has been used to treat menstrual irregularities and infertility in women. However, the cellular and molecular mechanisms underlying the effects of SM remain elusive. We investigated the potential protective effect of SM against chronic ovarian dysfunction and used bioinformatics analysis to identify its underlying mechanism in a mouse model of cyclophosphamide (CP)-induced diminished ovarian reserve. Female C57BL/6 mice were intraperitoneally injected with CP three times a week, followed by oral administration of distilled water (CP group) or SM (CP + SM group) for 4 weeks. Four weeks later, the effect of SM was assessed by ovarian tissue histological analysis, steroid hormone measurement, oocyte quality, and mRNA and microRNA microarray analysis in the ovaries. Although SM administration did not prevent CP-induced follicle loss in mice, the quality of oocytes was better in CP + SM mice than in CP mice. Gene expression analysis revealed that the expression of fertilisation- and ovarian follicle development-related genes was altered by CP treatment but normalized after SM administration. Further bioinformatics analysis showed possible interactions between differentially expressed mRNAs and microRNAs. Therefore, we demonstrated the protective effects of SM on ovarian function and oocyte maturation against CP-induced damage via multiple epigenetic mechanisms.


Sign in / Sign up

Export Citation Format

Share Document