HISTOCHEMICAL OBSERVATIONS ON THE GRANULOSA AND THECA INTERNA DURING FOLLICULAR DEVELOPMENT AND CORPUS LUTEUM FORMATION AND REGRESSION IN THE AMERICAN OPOSSUM

1968 ◽  
Vol 40 (2) ◽  
pp. 237-241 ◽  
Author(s):  
S. S. GURAYA

SUMMARY A study has been made of the histochemical changes which occur during follicular growth and formation and regression of the corpus luteum in the ovary of the American opossum. The granulosa cells show abundant cytoplasmic RNA. Some lipid bodies consisting of phospholipids are sparsely distributed among the granulosa cells. After ovulation, the granulosa cells undergo 'luteinization' to form the large luteal cells. The most striking histochemical change involved in the differentiation (or luteinization) of the granulosa follicle cell into a luteal cell is the development of abundant diffuse lipoproteins throughout the cytoplasm. Fine lipid granules consisting of phospholipids are also formed in the cytoplasm of luteal cells. The stromal elements of the theca interna, which contain some sparsely scattered phospholipid granules, do not show any histochemical change during corpus luteum formation. With the regression of luteal cells, coarse lipid granules consisting of cholesterol and cholesterol esters, triglycerides and some phospholipids accumulate abundantly in the cytoplasm. Some of these regressing luteal cells continue to persist in the ovarian stroma for some time.

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Zonghao Tang ◽  
Jiajie Chen ◽  
Zhenghong Zhang ◽  
Jingjing Bi ◽  
Renfeng Xu ◽  
...  

The increase of oxidative stress is one of the important characteristics of mammalian luteal regression. Previous investigations have revealed the essential role of reactive oxygen species (ROS) in luteal cell death during luteolysis, while it is unknown how ROS is regulated in this process. Considering the decrease of blood flow and increase of PGF2α during luteolysis, we hypothesized that the HIF-1α pathway may be involved in the regulation of ROS in the luteal cell of the late corpus luteum (CL). Here, by using a pseudopregnant rat model, we showed that the level of both HIF-1α and its downstream BNIP3 was increased during luteal regression. Consistently, we observed the increase of autophagy level during luteolysis, which is regulated in a Beclin1-independent manner. Comparing with early (Day 7 of pseudopregnancy) and middle CL (Day 14), the level of ROS was significantly increased in late CL, indicating the contribution of oxidative stress in luteolysis. Inhibition of HIF-1α by echinomycin (Ech), a potent HIF-1α inhibitor, ameliorated the upregulation of BNIP3 and NIX, as well as the induction of autophagy and the accumulation of ROS in luteal cells on Day 21 of pseudopregnancy. Morphologically, Ech treatment delayed the atrophy of the luteal structure at the late-luteal stage. An in vitro study indicated that inhibition of HIF-1α can also attenuate PGF2α-induced ROS and luteal cell apoptosis. Furthermore, the decrease of cell apoptosis can also be observed by ROS inhibition under PGF2α treatment. Taken together, our results indicated that HIF-1α signaling is involved in the regression of CL by modulating ROS production via orchestrating autophagy. Inhibition of HIF-1α could obviously hamper the apoptosis of luteal cells and the process of luteal regression.


1987 ◽  
Vol 40 (3) ◽  
pp. 331 ◽  
Author(s):  
William Hansel ◽  
Hector W Alila ◽  
Joseph P Dowd ◽  
Xiangzhong Yang

Evidence was cited to show that: (1) prostacyclin (PGI2) plays a luteotrophic role in the bovine corpus luteum and that products of the lipoxygenase pathway of arachidonic acid metabolism, especially 5-hydroxyeicosatetraenoic acid play luteolytic roles; (2) oxytocin of luteal cell origin plays a role in development, and possibly in regression, of the bovine corpus luteum; and (3) luteal cells arise from two sources; the characteristic small luteal cells at all stages of the o~strous cycle and pregnancy are of theca cell origin; the large cells are of granulosa cell origin early in the cycle, but a population of theca-derived large cells appears later in the cycle. Results of in vitro studies with total dispersed cells and essentially pure preparations of large and small luteal cells indicate that : (1) the recently described Ca2+ -polyphosphoinositol-protein kinase C second messenger system is involved in progesterone synthesis in the bovine corpus luteum; (2) activation of protein kinase C is stimulatory to progesterone synthesis in the small luteal cells; (3) activation of protein kinase C has no effect on progesterone synthesis in the large luteal cells; and (4) protein kinase C exerts its luteotrophic effect in total cell preparations, in part at least, by stimulating the production of prostacyclin. The protein kinase C system may cause down regulation of LH receptors in the large cells.


Reproduction ◽  
2005 ◽  
Vol 130 (1) ◽  
pp. 71-81 ◽  
Author(s):  
Kelli E Valdez ◽  
S Peder Cuneo ◽  
Adele M Turzillo

During atresia of bovine follicles, granulosa cells are lost through the controlled form of cell death, apoptosis. The purpose of this study was to characterize the regulation of apoptotic death of granulosa cells in dominant bovine follicles during the first wave of follicular development. Dominant follicles were collected from Holstein heifers on days 4, 6 or 8 of the first follicular wave (n= 5/day). Regulation of apoptosis in granulosa cells was examined by annexin V and propidium iodide staining; measurement of relative levels of mRNA encoding Bcl-2, Bcl-xL and Bax; and activity of caspase-3, -8 and -9. Steady-state levels of mRNA encoding four oxidative stress-response proteins were determined. Compared with day 4, the incidence of apoptotic and nonviable granulosa cells tended to increase on day 6, and numbers of nonviable cells were higher on day 8. The ratios of relative levels of mRNA encoding Bcl-2 to Bax and Bcl-xL to Bax were higher on day 6 than days 4 and 8. Activity of caspases-3 and -9 in granulosa cells did not change among the 3 days, while caspase-8 activity decreased on day 8 compared with days 4 and 6. Amounts of GSHPx, MnSOD and Cu/ZnSOD mRNA in granulosa cells were higher on day 8 than day 6. In theca interna, amounts of Cu/ZnSOD mRNA decreased between days 4 and 6. From the decreased production of estradiol and increased numbers of apoptotic and nonviable granulosa cells, we conclude that atresia of the dominant follicle is initiated between days 4 and 6 of the first follicular wave. However, apoptosis of granulosa cells does not appear to be initiated by changes in expression of oxidative stress-response proteins.


2016 ◽  
Vol 231 (3) ◽  
pp. 223-233 ◽  
Author(s):  
Liza Margareth Medeiros de Carvalho Sousa ◽  
Renata dos Santos Silva ◽  
Vanessa Uemura da Fonseca ◽  
Rafael Magdanelo Leandro ◽  
Thiago Senna Di Vincenzo ◽  
...  

This study aimed to determine in the canine corpus luteum throughout the dioestrus (1) the influence of insulin on glucose uptake; (2) the regulation of genes potentially involved; and (3) the influence of hypoxia on glucose transporter expression and steroidogenesis, after treatment with cobalt chloride (CoCl2). Glucose uptake by luteal cells increased 2.7 folds (P < 0.05) in response to insulin; a phenomenon related to increased expression of glucose transporter (GLUT) 4 and phosphorylation of protein kinase B (AKT). The gene expression of insulin receptor and SLC2A4 (codifier of GLUT4) genes after insulin stimulation increased on day 20 post ovulation (p.o.) and declined on day 40 p.o. (P < 0.05). Regarding potentially involved molecular mechanisms, the nuclear factor kappa B gene RELA was upregulated on days 30/40 p.o., when SLC2A4 mRNA was low, and the interleukin 6 (IL6) gene was upregulated in the first half of dioestrus, when SLC2A4 mRNA was high. CoCl2 in luteal cell cultures increased the hypoxia-inducible factor HIF1A/HIF1A and the SLC2A4/GLUT4 expression, and decreased progesterone (P4) production and hydroxyl-delta-5-steroid dehydrogenase 3 beta (HSD3B) mRNA expression (P < 0.05). This study shows that the canine luteal cells are responsive to insulin, which stimulates glucose uptake in AKT/GLUT4-mediated pathway; that may be related to local activity of RELA and IL6. Besides, the study reveals that luteal cells under hypoxia activate HIF1A-modulating luteal function and insulin-stimulated glucose uptake. These data indicate that insulin regulates luteal cells’ glucose disposal, participating in the maintenance and functionality of the corpus luteum.


1967 ◽  
Vol 39 (2) ◽  
pp. 163-171 ◽  
Author(s):  
A. S. EL-SHEIKH ◽  
FRANÇOIS B. SAKLA ◽  
SAFAA O. AMIN

SUMMARY The histological and functional changes of 31 corpora lutea of Egyptian buffaloes during the various phases of the oestrous cycle were studied. The volumes of the corpora lutea were calculated, the volume per cell, the cell volume and the volume of the intercellular spaces were estimated from transverse serial sections stained with haematoxylin and eosin, Mallory's triple stain or van Gieson's stain. The nuclear volumes were also determined and the cytoplasmic volume was calculated. The progesterone content was estimated using column absorption chromatography and a counter-current distribution system. It was concluded that the luteal cells increase both in volume and in number due to mitosis. The luteal cells decrease in volume after the 15th day after ovulation, the cells lose their distinct outlines in the regressive stage and disappear completely in the corpus albicans. There was a parallel increase in luteal cell volume and progesterone content until the 15th post-ovulatory day followed by a decrease in the regressive phase and disappearance of the hormone in the corpus albicans. A highly significant correlation (r = +0·875) was found between the progesterone content and the cytoplasmic volume. Progesterone concentration/g. luteal tissue increased from the corpus haemorrhagicum to the mature corpus luteum, decreased in the regressive corpus luteum and completely disappeared in the corpus albicans.


1998 ◽  
Vol 46 (9) ◽  
pp. 1043-1049 ◽  
Author(s):  
P. Bagavandoss ◽  
E. Helene Sage ◽  
Robert B. Vernon

In adult mammals, growth of new vasculature from extant blood vessels (angiogenesis) is rare in the absence of pathology. However, nonpathogenic angiogenesis occurs in the cycling ovary when the avascular postovulatory follicle transforms into a highly vascularized corpus luteum (CL). To improve our understanding of molecular mechanisms that regulate nonpathogenic vascular growth, we characterized the expression of two secreted matricellular proteins associated with angiogenesis, SPARC and thrombospondin (TSP), in postovulatory preluteal follicles and CL of hormone-primed immature rats. By indirect immunofluorescence with specific antibodies, we found SPARC in the cytoplasm of granulosa cells and thecal cells of preluteal follicles, in connective tissue cells of the ovarian interstitium, and in the oocyte nucleus. Administration of a luteinizing stimulus (chorionic gonadotropin) increased the expression of SPARC in granulosa cells. TSP was prominent in the basement membranes of growing follicles. Many cells in the early vascularizing CL expressed both SPARC and TSP. Neovascularization of CL was accompanied by expression of SPARC in nascent vessels and concentration of TSP in central avascular areas. In mature CL, steroidogenic luteal cells expressed both SPARC and TSP. Luteal cells of regressing CL retained SPARC to a variable degree but did not express TSP. The observed changes in expression of SPARC and TSP during development of the CL support distinct roles for these matricellular proteins in nonpathological morphogenesis and angiogenesis.


2018 ◽  
Vol 30 (1) ◽  
pp. 193
Author(s):  
P. Tanyapanyachon ◽  
O. Amelkina ◽  
K. Chatdarong

Kisspeptin (Kp) is considered one of the main regulators of the reproductive axis, exerting its effects via stimulating GnRH expression in the hypothalamus. Apart from its central localization in the hypothalamus, the presence of Kp has been reported in the ovary, with possible local function. To date, very little is known about the ovarian Kp in the domestic cat. Therefore, our aim was to investigate the presence and localization of Kp at different reproductive stages in domestic cat ovaries. Twenty ovaries were collected from free-ranging domestic cats (body weight 2.7–4.5 kg) after routine ovariohysterectomy. Reproductive stages were classified by ovarian gross morphology, vaginal cytology, and blood progesterone level. Ovarian samples were grouped into inactive (n = 6), follicular (n = 8), and luteal stages (n = 6). Tissues were fixed in 4% paraformaldehyde and processed routinely. Immunohistochemistry was performed using polyclonal rabbit Kp-10 primary antibody (AB9754; Millipore, Billerica, MA, USA) at 1:500 at 4°C overnight. Immunoreactive cells were identified by avidin-biotin-peroxidase system. Rat hypothalamic tissue was used as a positive control. Primary antibody was substituted with PBS and normal rabbit IgG as the negative and isotypic negative controls, respectively. In addition, primary antibody was incubated with metastin overnight and applied for preabsorption test. Negative, isotypic negative, and preabsorption tests showed no staining. Immunoreactive Kp was detected in the ovaries of all reproductive stages with no obvious changes in localization or intensity of staining between stages. Kisspeptin was present in the cytoplasm of oocytes, granulosa cells, and theca cells of preantral (primordial, primary, and secondary) follicles and antral follicles. Interestingly, in most follicles, Kp staining was more prominent in theca cells and oocytes compared with granulosa cells. In corpus luteum, Kp was localised in the cytoplasm of luteal cells, with more intense staining on the periphery of corpus luteum compared with the middle in 3 luteal samples, whereas the rest of the samples demonstrated homogeneous staining distribution. Apart from oocytes and steroidogenic cells, Kp was also present in the cytoplasm of cells of the ovarian surface epithelium. Our study for the first time demonstrated the presence and localization of Kp in the ovary of the domestic cats. The localization of Kp in the cat oocyte is similar to previous reports on hamsters and dogs, indicating a possible function in oocyte development. The staining in steroidogenic cells, mainly theca cells and luteal cells, is in good agreement with studies on hamsters, rats, humans, and marmosets, suggesting the possible local involvement of Kp in steroidogenesis. In addition, Kp staining in the ovarian surface epithelium suggests a possible role in the ovarian remodeling after ovulatory defects, as reported in humans and marmosets. This research was funded by the RGJ PhD program PHD/01882556; RG 7/2559.


Author(s):  
Christian Lee Andersen ◽  
Haeyeun Byun ◽  
Yuehuan Li ◽  
Shuo Xiao ◽  
Doris M Miller ◽  
...  

Abstract Certain chemotherapeutic drugs are toxic to ovarian follicles. The corpus luteum (CL) is normally developed from an ovulated follicle for producing progesterone (P4) to support early pregnancy. To fill in the knowledge gap about effects of chemotherapy on the CL, we tested the hypothesis that chemotherapy may target endothelial cells and/or luteal cells in the CL to impair CL function in P4 steroidogenesis using doxorubicin (DOX) as a representative chemotherapeutic drug in mice. In both mixed background mice and C57BL/6 mice, a single intraperitoneal injection of DOX (10 mg/kg) on 0.5 days post coitum (D0.5, post-ovulation) led to ~58% D3.5 mice with serum P4 levels lower than the serum P4 range in the PBS-treated control mice. Further studies in the C57BL/6 ovaries revealed that CLs from DOX-treated mice with low P4 levels had less defined luteal cords and disrupted collagen IV expression pattern, indicating disrupted capillary, accompanied with less differentiated luteal cells that had smaller cytoplasm and reduced StAR expression. DOX-treated ovaries had increased granulosa cell death in the growing follicles, reduced PCNA-positive endothelial cells in the CLs, enlarged lipid droplets and disrupted F-actin in the luteal cells. These novel data suggest that the proliferating endothelial cells in the developing CL may be the primary target of DOX to impair the vascular support for luteal cell differentiation and subsequently P4 steroidogenesis. This study fills in the knowledge gap about the toxic effects of chemotherapy on the CL and provides critical information for risk assessment of chemotherapy in premenopausal patients.


Reproduction ◽  
2006 ◽  
Vol 131 (1) ◽  
pp. 103-111 ◽  
Author(s):  
Alicia A Goyeneche ◽  
Jacquelyn M Harmon ◽  
Carlos M Telleria

The corpus luteum is a transient endocrine gland specializing in the production of progesterone. The regression of the corpus luteum involves an abrupt decline in its capacity for producing progesterone followed by its structural involution, which is associated with apoptosis of the luteal cells. An in vitro experimental approach is needed to study the molecular mechanisms underlying hormonal regulation of luteal cell death under defined experimental conditions. In this study, we investigated simian virus-40-transformed luteal cells to determine whether they can be driven to apoptosis and, if so, to define the intracellular pathway involved. Luteal cells were cultured in the presence or absence of fetal bovine serum for 24 or 48 h. Under serum starvation conditions, the luteal cells underwent growth arrest accompanied by cell death as evaluated by dye exclusion, and confirmed by two-color fluorescence cell viability/cytotoxicity assay. We next studied whether serum starvation-induced death of luteal cells occurred by apoptosis. Morphologic features of apoptosis were observed in cells stained with hematoxylin after being subjected to serum starvation for 48 h. The apoptotic nature was further confirmed by in situ 3′-end labeling and fragmentation of genomic DNA. Apoptosis of serum-deprived luteal cells was dependent upon caspase activation. Serum starvation induced cleavage of poly (ADP-ribose) polymerase (PARP), suggesting that caspase-3 had been activated under the stress of withdrawal of growth factors. This was confirmed by cleavage of full-length procaspase-3. Finally, the fact that serum starvation promoted the cleavage of full-length procaspase-9 and the decrease in the expression of endogenous Bid, a BH-3-only proapoptotic protein of the Bcl-2 family, indicates that the intrinsic (i.e., mitochondrial) pathway of apoptosis was activated. In summary, we have characterized an in vitro experimental model of luteal cell death that can be utilized to evaluate the role of hormones in apoptosis of luteal cells under defined culture conditions, and to study the mechanism of luteal regression.


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