388. Effect of hormonal therapy on plasma progesterone and 17β-estradiol levels in cows suffering from cystic ovarian degeneration

Hypokalemia produced different effects on steroid sex hormone concentrations in plasma and ovary in the mouse. Estradiol levels were slightly increased, whereas circulating progesterone was markedly decreased in all estrous periods. The preovulatory surge of gonadotropins and the secondary surge of follicle-stimulating hormone (FSH) at estrus were also decreased, but basal levels of both gonadotropins were unaffected. Supplementation with luteinizing hormone (LH), FSH, or gonadotropin-releasing hormone (GnRH) at proestrus rapidly normalized plasma and ovarian progesterone levels at this stage of the estrous cycle. Plasma progesterone levels at diestrus were restored only by combined treatment, at the periovulatory stage, with LH and FSH or GnRH but not by LH or FSH alone. The results demonstrate a lack of steroidogenic activity in the corpus luteum of the potassium-deficient mice and, furthermore, that FSH plays an important role in luteinization in the hypokalemic mice. We conclude that alteration of the transcellular potassium gradient may affect the regulation of the periovulatory surge of gonadotropins and progesterone secretion, probably by altering the release of GnRH from the hypothalamus. In addition, the results suggest that FSH may play a certain role as a luteotropic hormone in mice.

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Understanding resistance to hormonal therapy in estrogen avid breast cancer

Journal of Clinical Oncology ◽

10.1200/jco.2006.24.18_suppl.566 ◽

2006 ◽

Vol 24 (18_suppl) ◽

pp. 566-566

Author(s):

H. M. Linden ◽

S. Stekhova ◽

J. M. Link ◽

R. B. Livingston ◽

J. R. Gralow ◽

...

Keyword(s):

Breast Cancer ◽

Endocrine Therapy ◽

Hormonal Therapy ◽

Objective Response ◽

Response To Therapy ◽

Serum Estradiol ◽

Tumor Spread ◽

Imaging Protocol ◽

Estradiol Levels ◽

Er Expression

566 Background: The estrogen receptor (ER) is an essential target for endocrine therapy in breast cancer. We, and others, have tested an in vivo assay of ER function, [F-18]-16α-fluoroestradiol (FES) PET, which allows assessment of all sites of tumor spread and predicts response to hormonal therapy. However, not all patients with tumors bearing functional ER respond to therapy, suggesting the presence of mechanisms of resistance other than ER loss. Methods: 65 postmenopausal female patients with known ER+ metastatic (mostly bone and soft tissue dominant) breast cancer treated with aromatase inhibitors underwent PET FDG and FES imaging on an institutional imaging protocol (majority in second-line therapy). Hormone levels were assayed at the time of imaging, and biopsy specimens from either the primary tumor or metastasis were analyzed for expression of ER, PR, AR, PSA, HER2neu, and TopoIIα. Results: 49 (75%) patients had at least modest levels of retained ER expression, indicated by an average FES SUV > 1.5 at the tumor sites. We found serum estradiol, or estrone, levels >30pg/ml in 30% of patients. We found the majority of patients had PR, or AR expression, but few had EGFR or TopoIIα expression. FES SUV > 1.5 predicted response to therapy (p=.0006); no patient with an FES SUV < 1.5 had an objective response. Only 18/49 patients with SUV >1.5 responded to AI therapy. In the subset with FES SUV > 1.5, factors predicting lack of response to AI included PR negativity (p=.038) and/or detectable serum estradiol levels (p=.05). Conclusions: Quantitative PET FES predicts response to hormonal therapy. Estrogen levels may not be completely suppressed in patients on long-term AI therapy. Estradiol levels > 30pg/ml and lack of PR expression predict resistance to endocrine therapy in patients with tumors bearing functional ER expression. Efforts to monitor and reduce estradiol levels may offer therapeutic benefit to patients. No significant financial relationships to disclose.

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Association of microbial dynamics with urinary estrogens and estrogen metabolites in patients with endometriosis

PLoS ONE ◽

10.1371/journal.pone.0261362 ◽

2021 ◽

Vol 16 (12) ◽

pp. e0261362

Author(s):

Nhung Le ◽

Melissa Cregger ◽

Veronica Brown ◽

Julio Loret de Mola ◽

Pamela Bremer ◽

...

Keyword(s):

Hormonal Therapy ◽

Surgical Intervention ◽

Study Groups ◽

Estrogen Metabolism ◽

Strong Positive Correlation ◽

Microbial Dynamics ◽

Estrogen Metabolites ◽

Α Diversity ◽

17Β Estradiol ◽

Urinary Estrogens

Endometriosis is an estrogen dependent gynecological disease associated with altered microbial phenotypes. The association among endogenous estrogen, estrogen metabolites, and microbial dynamics on disease pathogenesis has not been fully investigated. Here, we identified estrogen metabolites as well as microbial phenotypes in non-diseased patients (n = 9) and those with pathologically confirmed endometriosis (P-EOSIS, n = 20), on day of surgery (DOS) and ~1–3 weeks post-surgical intervention (PSI). Then, we examined the effects of surgical intervention with or without hormonal therapy (OCPs) on estrogen and microbial profiles of both study groups. For estrogen metabolism analysis, liquid chromatography/tandem mass spectrometry was used to quantify urinary estrogens. The microbiome data assessment was performed with Next generation sequencing to V4 region of 16S rRNA. Surgical intervention and hormonal therapy altered gastrointestinal (GI), urogenital (UG) microbiomes, urinary estrogen and estrogen metabolite levels in P-EOSIS. At DOS, 17β-estradiol was enhanced in P-EOSIS treated with OCPs. At PSI, 16-keto-17β-estradiol was increased in P-EOSIS not receiving OCPs while 2-hydroxyestradiol and 2-hydroxyestrone were decreased in P-EOSIS receiving OCPs. GI bacterial α-diversity was greater for controls and P-EOSIS that did not receive OCPs. P-EOSIS not utilizing OCPs exhibited a decrease in UG bacterial α-diversity and differences in dominant taxa, while P-EOSIS utilizing OCPs had an increase in UG bacterial α-diversity. P-EOSIS had a strong positive correlation between the GI/UG bacteria species and the concentrations of urinary estrogen and its metabolites. These results indicate an association between microbial dysbiosis and altered urinary estrogens in P-EOSIS, which may impact disease progression.

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Effect of thymectomy on the female reproductive cycle in neonatal guinea pigs

Clinical and Experimental Reproductive Medicine ◽

10.5653/cerm.2019.02999 ◽

2020 ◽

Vol 47 (1) ◽

pp. 12-19

Author(s):

P. Murali ◽

J. Radhika ◽

D. Alwin

Keyword(s):

Reproductive Cycle ◽

Guinea Pigs ◽

Neonatal Period ◽

Reproductive Function ◽

Normal Female ◽

Vaginal Opening ◽

Estrus Cycle ◽

Reproductive Axis ◽

17Β Estradiol ◽

Estradiol Levels

Objective: The appropriate function of the hypothalamic-pituitary-gonadal axis is essential for maintaining proper reproductive function. In female mammals, the hypothalamic-pituitary-gonadal axis regulates reproductive changes that take place in the estrus cycle and are necessary for successful reproduction. This study was conducted to investigate the effect of thymectomy on the estrus cycle in neonatally thymectomized guinea pigs.Methods: In this study, 12 female guinea pigs, six thymectomized and six sham-operated, were studied. The effects of neonatal thymectomy at 5–7 days of age on parameters of the reproductive axis were examined in female guinea pigs. Gonadotropin and 17β-estradiol levels were assessed at regular intervals (days 0, 3, 6, 9, 12, and 15) of the estrus cycle, and the time of vaginal opening in the thymectomized and shamoperated guinea pigs was determined.Results: Significant reductions in gonadotropins and 17β-estradiol levels during estrus cycle were found in neonatally thymectomized female guinea pigs compared to sham-operated guinea pigs.Conclusion: The results of this study underscore the importance of the thymus in the neonatal period for normal female reproductive function.

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