scholarly journals Di(2-ethylhexyl) phthalate inhibits antral follicle growth, induces atresia, and inhibits steroid hormone production in cultured mouse antral follicles

2015 ◽  
Vol 284 (1) ◽  
pp. 42-53 ◽  
Author(s):  
Patrick R. Hannon ◽  
Katherine E. Brannick ◽  
Wei Wang ◽  
Rupesh K. Gupta ◽  
Jodi A. Flaws
Keyword(s):  
Steroid Hormone ◽  
Antral Follicle ◽  
Follicle Growth ◽  
Hormone Production ◽  
Antral Follicles ◽  
Ethylhexyl Phthalate

scholarly journals Dysregulation of Ovarian Follicular Development in Female Rat: LH Decreases FSH Sensitivity During Preantral-Early Antral Transition

Endocrinology ◽  
2013 ◽  
Vol 154 (8) ◽  
pp. 2870-2880 ◽  
Author(s):  
Makoto Orisaka ◽  
Katsushige Hattori ◽  
Shin Fukuda ◽  
Tetsuya Mizutani ◽  
Kaoru Miyamoto ◽  
...  
Keyword(s):  
Androgen Receptor ◽  
Polycystic Ovary ◽  
Follicular Development ◽  
Antral Follicle ◽  
Fsh Receptor ◽  
Mrna Levels ◽  
Female Rat ◽  
Preantral Follicle ◽  
Follicle Growth ◽  
Antral Follicles

Abstract Several clinical studies have shown a correlation of hypersecretion of LH and polycystic ovary syndrome (PCOS), infertility, and miscarriage in women, suggesting that chronically elevated LH impairs fertility. Growth arrest of small antral follicles in PCOS is also assumed to be associated with an abnormal endocrine environment involving increased LH stimulation, a hyperandrogenic milieu, and subsequent dysregulated FSH action in the ovarian follicles. In this study, we examined whether and how LH modulates follicular development and steroid production during preantral-early antral follicle transition by using a rat preantral follicle culture system. LH augments testosterone and estradiol production in preantral follicles via up-regulating mRNA abundance of CYP17A1 and CYP19A1. LH promotes rat preantral follicle growth, and the follicular size reaches that of early antral follicles in vitro, a response attenuated by the specific androgen receptor antagonist and a targeted disruption of androgen receptor gene. Sustained follicle stimulation by LH, but not by androgen, decreases FSH receptor mRNA levels and FSH receptor signaling and inhibits FSH-induced follicular growth. The data suggest that LH promotes preantral-early antral transition via the increased synthesis and growth-promoting action of androgen. However, chronic LH stimulation impairs FSH-dependent antral follicle growth by suppressing granulosa cell FSHR expression via the modulation of intraovarian regulators, including LH-induced thecal factors.

Recombinant FSH (Org32489) induces follicle growth and ovulation in the adult cyclic rat

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 ◽  
...  
Keyword(s):  
Mating Behaviour ◽  
Follicular Development ◽  
Antral Follicle ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Follicle Growth ◽  
Antral Follicles ◽  
Normal Number ◽  
Lhrh Antagonist ◽  
65 H

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

Ultrastructure of the basal lamina of bovine ovarian follicles and its relationship to the membrana granulosa

Reproduction ◽  
2000 ◽  
pp. 221-228 ◽  
Author(s):  
HF Irving-Rodgers ◽  
RJ Rodgers
Keyword(s):  
Basal Lamina ◽  
Granulosa Cells ◽  
Light And Electron Microscopy ◽  
Single Layer ◽  
Antral Follicle ◽  
Basal Cells ◽  
Preantral Follicles ◽  
Antral Follicles ◽  
Cellular Processes ◽  
Innermost Layer

Different morphological phenotypes of follicular basal lamina and of membrana granulosa have been observed. Ten preantral follicles (< 0. 1 mm), and 17 healthy and six atretic antral follicles (0.5-12 mm in diameter) were processed for light and electron microscopy to investigate the relationship the between follicular basal lamina and membrana granulosa. Within each antral follicle, the shape of the basal cells of the membrana granulosa was uniform, and either rounded or columnar. There were equal proportions of follicles </= 4 mm in diameter with columnar basal cells and with rounded basal cells. Larger follicles had only rounded basal cells. Conventional basal laminae of a single layer adjacent to the basal granulosa cells were observed in healthy follicles at the preantral and antral stages. However, at the preantral stage, the conventional types of basal lamina were enlarged or even partially laminated. A second type of basal lamina, described as 'loopy', occurred in about half the preantral follicles and in half the antral follicles </= 4 mm diameter. 'Loopy' basal laminae were not observed in larger follicles. 'Loopy' basal laminae were composed of basal laminae aligning the basal surface of basal granulosa cells, but with additional layers or loops often branching from the innermost layer. Each loop was usually < 1 microm long and had vesicles (20-30 nm) attached to the inner aspect. Basal cellular processes were also common, and vesicles could be seen budding off from these processes. In antral follicles, conventional basal laminae occurred in follicles with rounded basal granulosa cells. Other follicles with columnar cells, and atretic follicles, had the 'loopy' basal lamina phenotype. Thus, follicles have different basal laminae that relate to the morphology of the membrana granulosa.

Should fertile women quit drinking alcohol to produce better quality oocytes?

Zygote ◽  
2020 ◽  
pp. 1-3
Author(s):  
Burcu Ozbakir ◽  
Pinar Tulay
Keyword(s):  
Alcohol Consumption ◽  
Young Women ◽  
Antral Follicle ◽  
Antral Follicle Count ◽  
Control Group ◽  
Social Drinkers ◽  
Antral Follicles ◽  
Healthy Women ◽  
Significant Difference

Summary Alcohol consumption has long been shown to affect both fetal health and pregnancy. In this study, antral follicle count, maturation level of oocytes including morphological assessment and number of metaphase I (MI), metaphase II (MII) and germinal vesicle (GV) stage oocytes obtained from young women (age < 30 years old) with or without alcohol consumption were investigated. In total, 20 healthy women who were social drinkers and 36 healthy women who do not consume alcohol were involved in this study. Women in both study and control groups were undergoing controlled ovarian stimulation. The antral follicle count and the number and quality of the oocytes retrieved were evaluated and recorded. In total, 635 antral follicles, 1098 follicles and 1014 oocytes with 820 MII, 72 MI and 78 GV stage oocytes were collected from the social drinkers. In the control group, 628 antral follicles, 1136 follicles and 1085 oocytes with 838 MII, 93 MI and 102 GV stage oocytes were evaluated. The results of this study showed that the antral follicle count was very similar in both groups. The number of oocytes and MII stage oocytes was slightly higher in the control group, although it was not a significant difference. This study showed that although the consumption of alcohol may have adverse effects post-implantation, it may not have a solid effect during oogenesis in young women. The results of this study are especially important in clinical settings as some women who are social drinkers undergo in vitro fertilization treatments.

scholarly journals Mathematical modelling of oxygen transport-limited follicle growth

Reproduction ◽  
2007 ◽  
Vol 133 (6) ◽  
pp. 1095-1106 ◽  
Author(s):  
G P Redding ◽  
J E Bronlund ◽  
A L Hart
Keyword(s):  
Mathematical Modelling ◽  
Oxygen Transport ◽  
Size Range ◽  
Ovarian Follicle ◽  
Antral Follicle ◽  
Follicle Growth ◽  
Preantral Follicles ◽  
Formation Stage ◽  
Ultimate Fate ◽  
Further Development

Mathematical modelling was used to investigate oxygen transport in the developing ovarian follicle. In contrast to previous findings, the results show that oxygen can reach the oocyte in large preantral follicles. This is largely due to the inclusion of fluid voidage in the model and improved estimates of oxygen diffusion coefficients through the granulosa. The results also demonstrate that preantral follicles will eventually reach a size beyond which further growth will result in the follicle becoming increasingly anoxic. The predicted size range at which this occurs is consistent with the size range at which antrum formation is observed in many mammals. This suggests that the antrum formation stage of follicular growth may be pivotal to the further development and ultimate fate of the follicle, and that antrum formation itself may represent a mechanism by which the follicle can overcome oxygen limitations. This was supported through extension of the model to the antral follicle, which showed that antrum formation can provide a way in which the follicle can continue to grow and yet avoid becoming hypoxic. The results of the model were consistent with observed follicle development.

scholarly journals Involvement of hyaluronan synthesis in ovarian follicle growth in rats

Reproduction ◽  
2014 ◽  
Vol 147 (2) ◽  
pp. 189-197 ◽  
Author(s):  
Noriyuki Takahashi ◽  
Wataru Tarumi ◽  
Bunpei Ishizuka
Keyword(s):  
Ovarian Follicle ◽  
Primary Site ◽  
Corpora Lutea ◽  
Follicular Atresia ◽  
Follicle Growth ◽  
Adult Rats ◽  
Antral Follicles ◽  
Cell Layers ◽  
Ha Synthase

Most of the previous studies on ovarian hyaluronan (HA) have focused on mature antral follicles or corpora lutea, but scarcely on small preantral follicles. Moreover, the origin of follicular HA is unknown. To clarify the localization of HA and its synthases in small growing follicles, involvement of HA in follicle growth, and gonadotropin regulation of HA synthase (Has) gene expression, in this study, perinatal, immature, and adult ovaries of Wistar-Imamichi rats were examined histologically and biochemically and byin vitrofollicle culture. HA was detected in the extracellular matrix of granulosa and theca cell layers of primary follicles and more advanced follicles. Ovarian HA accumulation ontogenetically started in the sex cords of perinatal rats, and its primary site shifted to the intrafollicular region of primary follicles within 5 days of birth. TheHas1–3mRNAs were expressed in the ovaries of perinatal, prepubertal, and adult rats, and the expression levels ofHas1andHas2genes were modulated during the estrous cycle in adult rats and following administration of exogenous gonadotropins in immature acyclic rats. TheHas1andHas2mRNAs were predominantly localized in the theca and granulosa cell layers of growing follicles respectively. Treatments with chemicals known to reduce ovarian HA synthesis induced follicular atresia. More directly, the addition ofStreptomyceshyaluronidase, which specifically degrades HA, induced the arrest of follicle growth in anin vitroculture system. These results indicate that gonadotropin-regulated HA synthesis is involved in normal follicle growth.

The dare gene: steroid hormone production, olfactory behavior, and neural degeneration in Drosophila

Development ◽  
1999 ◽  
Vol 126 (20) ◽  
pp. 4591-4602 ◽  
Author(s):  
M.R. Freeman ◽  
A. Dobritsa ◽  
P. Gaines ◽  
W.A. Segraves ◽  
J.R. Carlson
Keyword(s):  
Nervous System ◽  
Steroid Hormones ◽  
Steroid Hormone ◽  
Larval Instar ◽  
Hormone Production ◽  
Ring Gland ◽  
Olfactory Stimuli ◽  
Steroid Hormone Signaling ◽  
Adrenodoxin Reductase ◽  
Strength Result

Steroid hormones mediate a wide variety of developmental and physiological events in insects, yet little is known about the genetics of insect steroid hormone biosynthesis. Here we describe the Drosophila dare gene, which encodes adrenodoxin reductase (AR). In mammals, AR plays a key role in the synthesis of all steroid hormones. Null mutants of dare undergo developmental arrest during the second larval instar or at the second larval molt, and dare mutants of intermediate severity are delayed in pupariation. These defects are rescued to a high degree by feeding mutant larvae the insect steroid hormone 20-hydroxyecdysone. These data, together with the abundant expression of dare in the two principal steroid biosynthetic tissues, the ring gland and the ovary, argue strongly for a role of dare in steroid hormone production. dare is the first Drosophila gene shown to encode a defined component of the steroid hormone biosynthetic cascade and therefore provides a new tool for the analysis of steroid hormone function. We have explored its role in the adult nervous system and found two striking phenotypes not previously described in mutants affected in steroid hormone signaling. First, we show that mild reductions of dare expression cause abnormal behavioral responses to olfactory stimuli, indicating a requirement for dare in sensory behavior. Then we show that dare mutations of intermediate strength result in rapid, widespread degeneration of the adult nervous system.

scholarly journals Effects of Chemical Mixtures on the Ovary

Reproduction ◽  
2021 ◽  
Author(s):  
Vasiliki E. Mourikes ◽  
Jodi A Flaws
Keyword(s):  
Ovarian Development ◽  
Steroid Hormone ◽  
Critical Role ◽  
Corpora Lutea ◽  
Chemical Mixtures ◽  
Hormone Production ◽  
Sex Steroid Hormone ◽  
Cellular Processes ◽  
Female Reproductive Health

The ovaries play a critical role in female reproductive health because they are the site of oocyte maturation and sex steroid hormone production. The unique cellular processes that take place within the ovary make it a susceptible target for chemical mixtures. Herein, we review the available data regarding the effects of chemical mixtures on the ovary, focusing on development, folliculogenesis, and steroidogenesis. The chemical mixtures discussed include those to which women are exposed to environmentally, occupationally, and medically. Following a brief introduction to chemical mixture components, we describe the effects of chemical mixtures on ovarian development, folliculogenesis, and steroidogenesis. Further, we discuss the effects of chemical mixtures on corpora lutea and transgenerational outcomes. Identifying the effects of chemical mixtures on the ovaries is paramount to preventing and treating mixture-inducing toxicity of the ovary that has long-term consequences such as infertility and ovarian disease.

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