scholarly journals 221CYSTIC BOVINE FOLLICLES ARE ASSOCIATED WITH AN ALTERATION IN LOCAL GENE AND PROTEIN EXPRESSION

2004 ◽  
Vol 16 (2) ◽  
pp. 232
Author(s):  
J. Greenaway ◽  
N. Linnerth ◽  
J. Petrik
Keyword(s):  
Growth Factor ◽  
Dairy Cattle ◽  
Protein Expression ◽  
Granulosa Cells ◽  
Follicular Development ◽  
Reproductive Function ◽  
Immunohistochemical Analysis ◽  
Receptor Expression ◽  
Gene And Protein Expression ◽  
Follicular Cysts

Formation of persistent follicular cysts is a prevalent problem for producers of domestic agricultural animals in North America. The most common group of animals affected is dairy cattle. This condition is problematic as it renders cattle anovulatory and infertile for the duration of the cyst. Various studies have assessed the incidence of follicular cysts in dairy cattle, revealing a range of prevalence of 9–26%. Although there is information regarding the incidence of this disorder, little is known of the etiology. It is known that a complex interaction occurs between the hypothalamus, anterior pituitary, and ovary to regulate normal reproductive function. Dysregulation at any of these sites could contribute to the formation of persistent follicular cysts. The objective of this study was to determine whether local changes in gene and protein expression are present in cystic follicles. Transvaginal aspirations from follicles that had been greater than 2.5-cm diameter for at least 10 days were collected. Aspirates were centrifuged, and granulosa cells and follicular fluid were separated. Granulosa cells were lysed, and RNA and protein was isolated. For immunohistochemistry, bovine slaughterhouse ovaries with follicles greater than 2.5cm in diameter were dissected, fixed, and processed. Western blot analysis and RT-PCR were performed on protein and RNA samples, respectively. Cystic and control follicles were analyzed for expression of vascular endothelial growth factor (VEGF) and its receptor VEGF-R2 and members of the insulin-like growth factor (IGF) family, which are known to mediate a host of cellular events during follicular development. Cystic follicles exhibited a significant increase in VEGF and IGF-I protein concentrations and a reduction in VEGF-R2 and the type 1 IGF receptor. Immunohistochemical analysis demonstrated increased ligand staining and reduced receptor expression in granulosa cells of cystic follicles. These results indicate that there is an altered growth factor profile in cystic follicles and suggest that intra- as well as extra-follicular dysregulation is important in the etiology of this reproductive disorder.

scholarly journals The effects of IGF-I on bovine follicle development and IGFBP-2 expression are dose and stage dependent

Reproduction ◽  
2006 ◽  
Vol 131 (3) ◽  
pp. 515-523 ◽  
Author(s):  
Kirsty A Walters ◽  
John P Binnie ◽  
Bruce K Campbell ◽  
David G Armstrong ◽  
Evelyn E Telfer
Keyword(s):  
Growth Factor ◽  
Granulosa Cells ◽  
Size Range ◽  
Regulatory System ◽  
Follicular Development ◽  
High Dose ◽  
Insulin Like Growth Factor ◽  
High Concentration ◽  
Antral Follicles ◽  
Igf I

This study aimed to determine the effect of insulin-like growth factor-I (IGF-I) on early antral bovine follicular development, and the expression of insulin-like growth factor-binding protein-2 (IGFBP-2). Antral follicles separated into three different size groups were cultured for 6 days in medium supplemented with either a low (10 ng/ml) or high (1 μg/ml) dose of human recombinant IGF-I. Oestradiol production by follicles in all size ranges, cultured in the presence of the high concentration of IGF-I, significantly increased by day 6 (P < 0.05). Follicles in the smallest size range, 165–215 μm, cultured in a high dose of IGF-I, were found to be significantly increased in size (P < 0.01). Oocyte health of the largest follicles (281–380 μm) was significantly improved by the addition of IGF-I to the culture medium. mRNA expression of IGFBP-2 was decreased in the granulosa cells of follicles, size range 216–280 μm, cultured with a high dose of IGF-I (P < 0.05). Granulosa cells (P < 0.05) and oocytes (P < 0.01) of the largest follicles (281–380 μm) showed a decrease in IGFBP-2 expression (protein) when cultured in the control and low-IGF-I treatment groups. Therefore, the response of a bovine follicle to IGF-I is both dose and stage dependent. This work supports a role for IGF-I in modulating somatic and germ-cell maturation and development in early antral follicles. Furthermore, the inverse relationship between the level of IGF-I stimulation and IGFBP-2 expression suggests a local regulatory system modulating IGF-I availability.

Daidzein affects steroidogenesis and oestrogen receptor expression in medium ovarian follicles of pigs

2013 ◽  
Vol 61 (1) ◽  
pp. 85-98 ◽  
Author(s):  
Anna Nynca ◽  
Dominika Słonina ◽  
Olga Jablońska ◽  
Barbara Kamińska ◽  
Renata Ciereszko
Keyword(s):  
Protein Expression ◽  
Granulosa Cells ◽  
Oestrogen Receptor ◽  
Receptor Expression ◽  
Progesterone Production ◽  
Progesterone Secretion ◽  
Mrna And Protein Expression ◽  
Induced Changes ◽  
Reproductive Processes

Daidzein, a phytoestrogen present in soybean products used in swine feed, has been demonstrated to affect both reproductive and endocrine functions. The aims of this study were to examine the in vitro effects of daidzein on (1) progesterone (P4) and oestradiol (E2) secretion by porcine luteinised granulosa cells harvested from medium follicles, and (2) the mRNA and protein expression of oestrogen receptors α and β (ERα and ERβ) in these cells. The influence of E2 on P4 secretion and ERα and ERβ expression in the granulosa cells of pigs was also investigated. It was found that daidzein inhibited progesterone secretion by luteinised granulosa cells isolated from medium follicles. In contrast, E2 did not affect progesterone production by these cells. Moreover, daidzein did not alter the granulosal secretion of E2. Both daidzein and E2 decreased mRNA expression of ERα in the cells examined. The expression of ERβ mRNA was not affected by daidzein but was inhibited by E2. ERα protein was not detected while ERβ protein was found in the nuclei of the cells. Daidzein and E2 upregulated the expression of ERβ protein in the cells. In summary, the phytoestrogen daidzein directly affected the porcine ovary by inhibiting progesterone production and increasing ERβ protein expression. Daidzein-induced changes in follicular steroidogenesis and granulosal sensitivity to oestrogens may disturb reproductive processes in pigs.

scholarly journals Heat stress diminishes gonadotropin receptor expression and enhances susceptibility to apoptosis of rat granulosa cells

Reproduction ◽  
2005 ◽  
Vol 129 (4) ◽  
pp. 463-472 ◽  
Author(s):  
Takashi Shimizu ◽  
Izumi Ohshima ◽  
Manabu Ozawa ◽  
Satoko Takahashi ◽  
Atsushi Tajima ◽  
...  
Keyword(s):  
Heat Stress ◽  
Granulosa Cells ◽  
Follicular Fluid ◽  
Follicular Development ◽  
Receptor Expression ◽  
Female Rats ◽  
Aromatase Activity ◽  
Mrna Levels ◽  
Gonadotropin Receptor ◽  
Estradiol Levels

Heat stress inhibits ovarian follicular development in mammalian species. We hypothesized that heat stress inhibits the function of follicular granulosa cells and suppresses follicular development. To test this, immature female rats were injected with pregnant mare serum gonadotropin (PMSG) at 48 h after the start of temperature treatment (control: 25 °C, 50% RH; heat stress: 35 °C, 70% Relative Humidity). The ovaries and granulosa cells of follicles at different developmental stages were analyzed for gonadotropin receptor levels and aromatase activity; estradiol levels were measured in follicular fluid. Before injection, heat stress diminished only the amount of FSH receptor on granulosa cells of antral follicles. During PMSG-stimulated follicular development, heat stress strongly inhibited gonadotropin receptor levels and aromatase activity in granulosa cells, and estradiol levels in the follicular fluid of early antral, antral and preovulatory follicles. To examine apoptosis and mRNA levels of bcl-2 and bax in granulosa cells, follicles harvested 48 h after PMSG injection were cultured in serum-free conditions. Heat-stressed granulosa cells showed a time-dependent increase in apoptosis. The bcl-2 mRNA levels were similar in control and heat-stressed granulosa cells; bax mRNA levels were increased in heat-stressed granulosa cells. According to these results, heat stress inhibits expression of gonadotropin receptors in granulosa cells and attenuates estrogenic activity of growing follicles, granulosa cells of heat-stressed follicles are susceptible to apoptosis, and the bcl2/bax system is not associated with heat-stress-induced apoptosis of granulosa cells. Our study suggests that decreased numbers and function of granulosa cells may cause ovarian dysfunction in domestic animals in summer.

IL-13-induced Clara cell secretory protein expression in airway epithelium: role of EGFR signaling pathway

2002 ◽  
Vol 283 (1) ◽  
pp. L67-L75 ◽  
Author(s):  
Suil Kim ◽  
Jae Jeong Shim ◽  
Pierre-Regis Burgel ◽  
Iris F. Ueki ◽  
Trang Dao-Pick ◽  
...  
Keyword(s):  
Growth Factor ◽  
Protein Expression ◽  
Tyrosine Kinase ◽  
Tyrosine Kinase Inhibitor ◽  
Kinase Inhibitor ◽  
Growth Factor Receptor ◽  
Secretory Protein ◽  
Clara Cell ◽  
Clara Cell Secretory Protein ◽  
Gene And Protein Expression

Previous work showed that the Th2 cytokine interleukin (IL)-13 induces goblet cell metaplasia via an indirect mechanism involving the expression and subsequent activation of epidermal growth factor receptor (EGFR). Because Clara cell secretory protein (CCSP) expression has been reported in cells that express mucins, we examined the effect of IL-13 on CCSP gene and protein expression in pathogen-free rat airways and in pulmonary mucoepidermoid NCI-H292 cells. Intratracheal instillation of IL-13 induced CCSP mRNA in epithelial cells without cilia within 8–16 h, maximal between 24 and 48 h; CCSP immunostaining increased in a time-dependent fashion, maximal at 48 h. The CCSP immunostaining was localized in nongranulated secretory cells and goblet cells and in the lumen. Pretreatment with the selective EGFR tyrosine kinase inhibitor BIBX1522, cyclophosphamide (an inhibitor of bone marrow leukocyte mobilization), or a blocking antibody to IL-8 prevented CCSP staining. Treatment of NCI-H292 cells with the EGFR ligand transforming growth factor-α, but not with IL-13 alone, induced CCSP gene and protein expression. Selective EGFR tyrosine kinase inhibitors, BIBX1522 and AG1478, prevented CCSP expression in NCI-H292 cells, but the platelet-derived growth factor receptor tyrosine kinase inhibitor AG1295 had no effect. These findings indicate that IL-13 induces CCSP expression via an EGFR- and leukocyte-dependent pathway.

Evaluation of vascular endothelial growth factor gene and protein expression in canine metastatic mammary carcinomas

2016 ◽  
Vol 79 (11) ◽  
pp. 1097-1104 ◽  
Author(s):  
Talita M.M. Raposo-Ferreira ◽  
Rosana C.L. Salvador ◽  
Erika M. Terra ◽  
Juarez H. Ferreira ◽  
Ivan José Vechetti-Junior ◽  
...  
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Growth Factor ◽  
Protein Expression ◽  
Vascular Endothelial ◽  
Factor Gene ◽  
Mammary Carcinomas ◽  
Growth Factor Gene ◽  
Gene And Protein Expression ◽  
Endothelial Growth Factor
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