Folliculogenesis

Mariana, J. C.; Monniaux, Danielle; Driancourt, Marc Antoine; Mauléon, P.

doi:10.1016/b978-0-08-057109-6.50009-4

Cited by 17 publications

(15 citation statements)

References 300 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In a similar way, LH receptors are expressed by granulosa cells of follicles larger than 3 mm diameter, beyond which the sensitivity of granulosa cells to LH increases to high levels in preovulatory follicles [1,3,39,40]. In parallel with these changes, granulosa cells progressively lose their proliferative activity [14]. In sheep, we have previously shown that the proliferative activity of granulosa cells decreases drastically in follicles between 2 and 6 mm diameter, and that this decrease corresponds to cell cycle exit [21,24].…”

Section: Introductionmentioning

confidence: 80%

Fraction of proliferating cells in granulosa during terminal follicular development in high and low prolific sheep breeds

2000

View full text Add to dashboard Cite

-During terminal development of antral follicles, granulosa cells progressively lose their proliferative activity. Romanov (ovulation rate = 3) and Ile-de-France (ovulation rate = 1) breeds of sheep were compared for fractions of proliferating granulosa cells, determined by in vitro continuous [ 3 H] thymidine labelling. In both breeds, the fraction of proliferating cells decreased with increasing follicular size according to a sigmoid-shaped curve. After linearization, the slope of the regression line was higher (in absolute value) in Romanov, compared to Ile-de-France ewes (p = 0.02). In vivo FSH treatment led to a decrease in the slope of the regression line in Romanov ewes only (p = 0.03). These results suggest that during terminal follicular development (1) the rate of cell cycle exit is higher in granulosa cells of Romanov, compared to Ile-de-France follicles, and (2) Romanov granulosa cells are more responsive to exogenous FSH in term of proliferation. These mechanisms may underlie differential dynamics of follicular development in poly-and mono-ovulating breeds of sheep. ovary / follicle / growth / cell cycle / ovulation rate Résumé -Proportion de cellules de granulosa proliférantes dans les follicules ovariens en cours de développement terminal dans deux races ovines de prolificités différentes. Au cours du développement terminal des follicules ovariens, les cellules de granulosa perdent progressivement leur activité de prolifération. Les proportions de cellules de granulosa proliférantes ont été déterminées par une technique de marquage continu in vitro à la thymidine tritiée, dans deux races ovines de prolificités différentes, la race Romanov (nombre d'ovulations = 3) et la race Ile-de-France (nombre d'ovulations = 1). Dans ces deux races, les résultats ont montré que la proportion de cellules de granulosa proliférantes diminue selon une courbe sigmoïde quand la taille des follicules à antrum augmente. Après linéarisation, la pente de la droite de régression est plus forte (en valeur absolue) dans la race Reprod. Nutr. Dev. 40 (2000) 295-304 295

show abstract

Section: Introductionmentioning

confidence: 80%

Fraction of proliferating cells in granulosa during terminal follicular development in high and low prolific sheep breeds

2000

View full text Add to dashboard Cite

show abstract

“…Our results suggest that ECM components of follicular BM act as survival factors on follicular granulosa cells in porcine ovaries. Key words: Apoptosis, Extracellular Matrix, Granulosa cell, Atretic follicle, Porcine ovary.More than 99% of ovarian follicles undergo atresia at various stages of development in mammalian ovaries [1,2]. Follicular atresia is a key reproductive phenomenon which decided the follicles that will not ovulate in the ovary.…”

mentioning

confidence: 99%

Interactions of Apoptosis and Extracellular Matrices in Granulosa Cells of Atretic Follicles in Porcine Ovaries.

et al. 1999

View full text Add to dashboard Cite

Abstract:The process of apoptosis of follicular granulosa cells in porcine ovaries during follicular atresia was investigated by in situ DNA 3'end-labeling at the level of individual cells. Histochemical changes in the follicular basement membrane (BM) were visualized by immunofluorescent staining of BM extracellular matrix (ECM) components, i.e. type IV collagen, laminin and fibronectin. At the first stage, granulosa cells located on the inner surface of the granulosa layer appeared to undergo apoptosis, followed by neighboring granulosa cells. No apoptotic granulosa cells making tight contact with intact BM were observed. Detachment and degeneration of the granulosa cell layer and fragmentation of BM occurred in follicles at the advanced stage of atresia. Finally, intermittent structures of BM and subsequent invasion of macrophages and fibroblasts were observed. Therefore we concluded that granulosa cell apoptosis is an initial symptom of follicular atresia in the porcine ovaries, and the degradation of BM follows granulosa cell apoptosis in the pig. Our results suggest that ECM components of follicular BM act as survival factors on follicular granulosa cells in porcine ovaries. Key words: Apoptosis, Extracellular Matrix, Granulosa cell, Atretic follicle, Porcine ovary.More than 99% of ovarian follicles undergo atresia at various stages of development in mammalian ovaries [1,2]. Follicular atresia is a key reproductive phenomenon which decided the follicles that will not ovulate in the ovary. Despite its critical role during the recruitment of follicles for ovulation, the mechanisms of the cellular and molecular events are not well understood yet. Despite species-specific differences, it is generally accepted that the earlier stages of ovarian follicular atresia are correlated with disorganization and degeneration of follicular granulosa cells [2,3]. Early studies [4][5][6][7] showed that both enhanced DNA degradation and ladder formation, hallmarks of apoptotic cell death, occur in granulosa cells of atretic follicles, and that apoptosis, originally reported by Kerr et al. [8], plays a key role in mammalian follicular atresia. Our previous detailed studies of the mechanism of follicular atresia in porcine ovaries demonstrated that degeneration of the atretic follicles can be explained in part by apoptosis of granulosa cells [9][10][11][12][13][14][15][16][17][18][19][20][21], and that the alteration of glycoconjugates of cellsurface and intercellular components in granulosa cells during follicular atresia are involved in some processes of ovarian follicular atresia and granulosa cell apoptosis [22][23][24][25].The extracellular matrix (ECM) components play important roles in the maintenance of homeostasis of organs and cells [26]. The relationship between ECM and cells that adhere to it can play important regulatory roles in many basic cellular processes by influencing enzyme activity [27,28] and phospholipid metabolism [29], and by modifying transcriptional and transitional activities of the cell [30]. These...

show abstract

“…In addition, it is thought that some local intraovarian compounds play a role in the atresia of follicles (Webb and Armstrong, 1998). Furthermore, there is a significant decrease in oestradiol and an increase in progesterone content of atretic follicles; the former is seen in parallel with the reduction of aromatase activity of granulosa cells (Mariana et al, 1991;Stevenson, 1997).…”

Section: Discussionmentioning

confidence: 80%

“…Cows with serum progesterone levels below 3.8 nmol/l were classified as being in the follicular phase and those with levels above 3.8 nmol/l in the luteal phase (Mariana et al, 1991). Follicles were classified according to their diameters as large (≥ 8 mm) or small (< 8 mm).…”

Section: Classification Of Folliclesmentioning

confidence: 99%

Comparison of leptin levels in serum and follicular fluid during the oestrous cycle in cows

Dayı¹,

Bediz²,

Musal³

et al. 2005

Acta Veterinaria Hungarica

View full text Add to dashboard Cite

Leptin is mainly synthesised in white adipose tissue. Besides its effects on body weight and metabolic homeostasis, leptin also has effects on puberty, sexual maturation and reproduction. In this study the relationship between leptin, IGF-1, oestradiol (E 2 ) and progesterone levels were investigated in serum and follicular fluid from cows. This study included 72 healthy, Brown Swiss cows aged 4-5 years. Samples from the jugular vein and follicular fluids were collected. Phases of the oestrus cycle of cows were classified according to their serum progesterone levels (< 3.18 nmol/l, follicular phase and the others as luteal phase). Follicles were grouped as large (≥ 8 mm) or small (< 8 mm). Leptin, IGF-1, oestradiol and progesterone levels were measured from serum and follicular fluid. Leptin concentrations were found to be significantly higher in luteal-phase follicular fluid of small follicles (P < 0.05). These were classified as atretic follicles. There was a positive correlation between serum and follicular fluid leptin levels in the luteal phase. Serum leptin was found to have a positive correlation with follicular fluid progesterone level (P = 0.01) in the preovulatory follicles. The present study shows that there is a relationship between the concentration of leptin in follicular fluid and atresia in small follicles.

show abstract

Folliculogenesis

Cited by 17 publications

References 300 publications

Fraction of proliferating cells in granulosa during terminal follicular development in high and low prolific sheep breeds

Fraction of proliferating cells in granulosa during terminal follicular development in high and low prolific sheep breeds

Interactions of Apoptosis and Extracellular Matrices in Granulosa Cells of Atretic Follicles in Porcine Ovaries.

Comparison of leptin levels in serum and follicular fluid during the oestrous cycle in cows

Contact Info

Product

Resources

About