High concentrations of the vascular endothelial growth factor and interleukin-8 in ovarian endometriomata.
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Patients with endometriosis are characterized by the ability of the endometrium to implant and by the peritoneal response to the tissue; angiogenic factors may play a significant role in the aetiology of endometriosis supporting the implantation of ectopic endometrial cells. Vascular endothelial growth factor (VEGF) is a mitogen, morphogen and chemoactractant for endothelial cells and, in vivo, it is a powerful mediator for vessel permeability. Interleukin-8 (IL-8) is a chemoatractant for neutrophils and is a potent angiogenic factor. Women (n = 20) with ovarian endometriomata and 10 women with follicular cysts were enrolled in this study to investigate the role of VEGF and IL-8 in the development and maintenance of ovarian endometriomata. Cystic fluids were collected by laparoscopy, immediately centrifuged and stored until the enzyme-linked immunosorbent assays were performed. The VEGF and IL-8 concentrations were found to be significantly higher in the fluids of the ovarian endometriomata than in those of the follicular cysts of controls (P < 0.001 and P < 0.001 respectively); in addition, a significant inverse correlation between the VEGF cystic fluid concentrations and the diameter of the endometriotic adnexal masses was found (r = -0.56, P = 0.01). The evidence that the high concentrations of VEGF and IL-8 are present in the ovarian endometriomata indicates that angiogenesis could be a specific event both for the progression and maintenance of such cysts. (+info)
Dominant bovine ovarian follicular cysts express increased levels of messenger RNAs for luteinizing hormone receptor and 3 beta-hydroxysteroid dehydrogenase delta(4),delta(5) isomerase compared to normal dominant follicles.
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The objective was to compare ovarian steroids and expression of mRNAs encoding cytochrome P450 side-chain cleavage, cytochrome P450 17 alpha-hydroxylase, cytochrome P450 aromatase, 3 beta-hydroxysteroid dehydrogenase Delta(4),Delta(5) isomerase, LH, and FSH receptors and estrogen receptor-beta in ovaries of cows with dominant and nondominant ovarian follicular cysts and in normal dominant follicles. Estradiol-17 beta, progesterone, and androstenedione concentrations were determined in follicular fluid using specific RIAs. Dominant cysts were larger than young cysts or dominant follicles, whereas nondominant cysts were intermediate. Estradiol-17 beta (ng/ml) and total steroids (ng/follicle) were higher in dominant cysts than in dominant follicles. Expression of LH receptor and 3 beta-hydroxysteroid dehydrogenase mRNAs was higher in granulosa cells of dominant cysts than in dominant follicles. Nondominant cysts had higher follicular concentrations of progesterone, lower estradiol-17 beta concentrations, and lower expression of steroidogenic enzyme, gonadotropin receptor, and estrogen receptor-beta mRNAs than other groups. In summary, increased expression of LH receptor and 3 beta-hydroxysteroid dehydrogenase mRNAs in granulosa and increased follicular estradiol-17 beta concentrations were associated with dominant cysts compared to dominant follicles. Study of cysts at known developmental stages is useful in identifying alterations in follicular steroidogenesis. (+info)
Serous cysts are a benign component of the cyclic ovary in the guinea pig with an incidence dependent upon inhibin bioactivity.
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Ovaries were collected from normal cycling female guinea pigs on each day of the estrous cycle (n = 5 per day) for histological analysis of ovarian morphology. Three types of ovarian cysts were observed: serous cysts, follicular cysts and parovarian cysts. The most common were serous cysts (cystic rete ovarii), which were present throughout the estrous cycle with an overall incidence of 63.5% (54 out of 85 animals). Follicular cysts occurred in 22.4% of guinea pigs overall (19 out of 85). Only one parovarian cyst (1 out of 85) was observed in the present experiment. Follicular cysts always coincided with serous cysts and were less common during diestrus. The incidence of serous cysts did not vary significantly across the estrous cycle. In a second experiment, cycling female guinea pigs were arrested in a prolonged luteal phase by a progesterone implant in order to achieve ovarian synchrony. They were then treated with inhibin antiserum (0.5 or 1 ml per animal i.v.; n = 6 per group) or normal goat serum (controls; n = 6 per group). There was a dose dependent increase in the incidence of serous ovarian cysts following passive immunization against the inhibin alpha-subunit. These results suggest that serous cysts are a normal component of the cyclic guinea pig ovary and that alterations in the inhibin-follicle-stimulating hormone system appear to modulate the incidence of serous ovarian cysts in this species. (+info)
Relationship among insulin-like growth factor-I, blood metabolites and postpartum ovarian function in dairy cows.
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The relationship among nutritional status, systemic insulin-like growth factor-I (IGF-I) and ovarian function early postpartum were investigated. A total of 27 Holstein-Friesian cows, 10 that cycled normally within 20 days postpartum, 5 diagnosed with follicular cysts, 8 with persistent corpus luteum (CL) after the first ovulation postpartum and 4 with inactive ovaries were used for the study. Blood samples were collected 1-3 times per week, for 60 days pre- and postpartum, for IGF-I, progesterone, estradiol, free fatty acids (FFA), blood urea nitrogen (BUN), and aspartate aminotransferase (AST) determination. Inactive ovary and cystic cows had a higher body condition score before calving and lost more condition than normal or persistent CL cows. Immediately postpartum, IGF-I levels were higher and rose sharply in cows that cycled normally than in cystic, inactive ovary or persistent CL cows. At calving and early postpartum, FFA was higher in inactive ovary and cystic than in normal and persistent CL cows. There was a significant strong positive relationship between IGF-I and BUN, and strong negative relationships between IGF-I and FFA and AST in all groups. There was a positive relationship between serum IGF-I and estradiol in normal cystic and inactive ovary cows. This study found that overconditioned cows during the dry period or at calving, lost more body condition postpartum. These cows also had a deeper and longer period of negative energy balance (NEB), poor liver function and low circulating IGF-I concentrations early postpartum. Such cows were likely to have poor reproductive function as seen in development of cystic ovaries, persistent CL and inactive ovary. Changes in serum IGF-I early postpartum may help predict both nutritional and reproductive status in dairy cattle. (+info)
Desmoglein isotype expression in the hair follicle and its cysts correlates with type of keratinization and degree of differentiation.
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Within stratified squamous epithelia, such as the epidermis, desmogleins are generally expressed in a differentiation-specific manner. Similar to the epidermis, the hair follicle is compartmentalized into a hierarchy of cell types based on their level of differentiation. Relatively undifferentiated stem cells in the bulge can generate epidermis, sebaceous gland, and hair bulb matrix cells. The latter give rise to at least six different cell types that keratinize as they move up the hair shaft and inner root sheath. Here, we examined expression patterns of the desmoglein isotypes, desmogleins 1, 2, and 3 in the cutaneous epithelium, and discovered that desmoglein 1 and 2 expression correlated with the state of differentiation of defined populations within the hair follicle. Desmoglein 2 was highly expressed by the least differentiated cells of the cutaneous epithelium, including the hair follicle bulge of the fetus and adult, bulb matrix cells, and basal layer of the outer root sheath. In contrast, desmoglein 1 defined more differentiated cell populations, and was expressed in epidermal suprabasal cells, the inner root sheath, and the innermost layers of the outer root sheath. We found that the expression pattern of desmoglein 3 correlated with different types of keratinization. In areas of trichilemmal keratinization in the follicle, and in cysts arising from these areas, desmoglein 3 was expressed throughout all layers of the outer root sheath and cyst wall. In areas of epidermal-like keratinization, such as in the infundibulum and in epidermal inclusion cysts, desmoglein 3 expression was limited mainly to the basal layer. We conclude that desmoglein expression patterns define compartments of cells in similar states of differentiation within the cutaneous epithelium, and reveal a hierarchy of differentiation among these compartments. (+info)
Adenomatous hyperplasia of the thyroid gland in beluga whales (Delphinapterus leucas) from the St. Lawrence Estuary and Hudson Bay, Quebec, Canada.
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We evaluated thyroid gland lesions in beluga whales (Delphinapterus leucas) from the St. Lawrence Estuary (n = 16) and Hudson Bay (n = 14). Follicular cysts and nodules of adenomatous hyperplasia of the thyroid gland were found in eight and nine adults from the St. Lawrence Estuary (n = 10), respectively, and in four and six adults from Hudson Bay (n = 14), respectively. The total volume of the lesions of thyroid adenomatous hyperplasia was positively correlated with age in both populations. Comparison between populations could not be performed because of differences in age structures of sample groups. Beluga whales from both populations have unique thyroid lesions among marine mammals. (+info)
Immunohistochemical localization of 3beta-hydroxysteroid dehydrogenase in the granulosa and theca interna layers of bovine cystic follicles.
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The aim of the present study was to determine whether the alteration of population of cells containing 3beta-hydroxysteroid dehydrogenase (3beta-HSD) is responsible for the formation of cystic follicles. Paraffin sections of healthy (2 to 5 mm in diameter), atretic (2 to 5 mm) and cystic follicles (more than 25 mm) were immunohistochemically stained with rabbit polyclonal antibody to bovine 3beta-HSD. The 3beta-HSD-positive cells were counted in 4 different regions of the follicles from the apical to the basal side. The frequencies of 3beta-HSD-positive granulosa cells in cystic follicles were significantly higher than those in the healthy follicles (P<0.05), although the number of 3beta-HSD-positive granulosa cells in the cystic follicle were fewer than half the cells (30 to 40%) and was much smaller than that in preovulatory follicles (Conley et al., 1995). The frequencies of 3beta-HSD-positive cells were higher in the granulosa layer and lower in the theca interna layer of the cystic follicles than the atretic follicles. These results suggest that the differentiation of granulosa cells to express 3beta-HSD might be insufficient in cystic follicles and accordingly they fail to ovulate. The differences of frequencies of 3beta-HSD-positive cells in the granulosa and theca interna layers between cystic and atretic follicles may be one of the reasons why regression is delayed in cystic follicles. (+info)
Studies on the regulation of expression of luteinizing hormone receptor in the ovary and the mechanism of follicular cyst formation in ruminants.
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In the series of studies, changes of expression and regulation of luteinizing hormone (LH) receptor in the ovary of domestic ruminants were examined. Furthermore, mechanisms of formation of follicular cysts in domestic ruminants, caused by stress and so on, were endocrinologically elucidated. Results of the studies provide the following conclusions. (1) The quantity of LH receptor in the bovine antral follicles increases rapidly in the latter stage of its development. (2) The quantity of LH receptor and its mRNA in the bovine and caprine corpus luteum increase during their developments. The increase of the receptor in the caprine luteal development is regulated by LH through the receptor mRNA level. (3) At least, three splice variants of LH receptor mRNA exist in the bovine luteal tissue and the variant receptors are expressed at different cellular sites according to its structure. (4) Intracellular consecutive cysteine residues of LH receptor are palmitoylated and thereby inhibit internalization of the receptor. (5) As a mechanism of the bovine follicular cyst caused by stress, it is suggested that increased secretions of progesterone and cortisol from the adrenal gland exert inhibitory effects on the hypothalamus and follicle, respectively, and subsequently LH and FSH surges are blocked, then finally ovulation is suppressed and the follicle becomes cystic. (+info)