412 research outputs found
AMH in PCOS: Controlling the ovary, placenta, or brain?
Polycystic ovary syndrome (PCOS) is a very heterogeneous disease of which the exact pathophysiological mechanisms remain unknown. In PCOS, serum anti-Müllerian hormone (AMH) levels are significantly increased. AMH is a member of the transforming growth factor β family and is expressed by growing follicles in the ovaries. In PCOS, the transcriptional regulation of AMH and AMHR2 is altered, increasing and prolonging its temporal expression pattern. Moreover, the recently discovered extragonadal effects of AMH suggest that there might be a crosstalk between the ovary–placenta–brain. This review summarizes the recent findings concerning AMH and its role in the etiology of PCOS
Anti-Müllerian Hormone and Ovarian Reserve: Update on Assessing Ovarian Function
CONTEXT: Anti-müllerian hormone (AMH) is produced by granulosa cells of small, growing follicles in the ovary. Serum AMH levels strongly correlate with the number of growing follicles, and therefore AMH has received increasing attention as a marker for ovarian reserve. This review summarizes recent findings and limitations in the application of serum AMH in ovarian reserve assessment. EVIDENCE ACQUISITION: A PubMed search was conducted to find recent literature on the measurements and use of serum AMH as a marker for ovarian reserve. EVIDENCE SYNTHESIS: Serum AMH levels are measured to assess the "functional ovarian reserve," a term that is preferred over "ovarian reserve," since AMH levels reflect the pool of growing follicles that potentially can ovulate. Serum AMH levels are used in individualized follicle-stimulating hormone dosing protocols and may predict the r
Anti-Mullerian Hormone: Molecular Mechanism of Action
During early fetal development. the primitive urogenital system is
bipotential and can develop into a male or female direction, depending on
the chromosomal sex of the fetus. In this chapter, regulatory factors of sex
determination and differentiation are described. The roles of two testicular
hormones, testosterone and anti-Mullerian hormone (AMH), which are
essential for proper differentiation of the internal genitalia, are discussed
Regulation of ovarian function: the role of anti-Mullerian hormone
Anti-Mullerian hormone (AMH), also known as Mullerian inhibiting
substance, is a member of the transforming growth factor beta superfamily
of growth and differentiation factors. In contrast to other members of the
family, which exert a broad range of functions in multiple tissues, the
principal function of AMH is to induce regression of the Mullerian ducts
during male sex differentiation. However, the patterns of expression of
AMH and its type II receptor in the postnatal ovary indicate that AMH may
play an important role in ovarian folliculogenesis. This review describes
several in vivo and in vitro studies showing that AMH participates in two
critical selection points of follicle development: it inhibits the
recruitment of primordial follicles into the pool of growing follicles and
also decreases the responsiveness of growing follicles to FSH
Circulating steroid hormone variations throughout different stages of prostate cancer
Steroid hormones play a central role in the maintenance and progression of prostate cancer. The androgen receptor is the primary driver of tumor cell proliferation and is activated by the androgens testosterone and 5α-dihydrotestosterone. Inhibition of this pathway through medical or surgical castration improves survival in the majority of advanced prostate cancer patients. However, conversion of adrenal androgen precursors and alternative steroidogenic pathways have been found to contribute to tumor progression and resistance to treatment. The emergence of highly accurate detection methods allows us to study steroidogenic mechanisms in more detail, even after treatment with potent steroidogenic inhibitors such as the CYP17A1 inhibitor abiraterone. A clear overview of steroid hormone levels in patients throughout the local, metastatic and castration-resistant stages of prostate cancer and treatment modalities is key toward a better understanding of their role in tumor progression and treatment resistance. In this review, we summarize the currently available data on steroid hormones that have been implicated in the various stages of prostate cancer. Additionally, this review addresses the implications of these findings, highlights important studies in this field and identifies current gaps in literature
Sex Difference in Corticosterone-Induced Insulin Resistance in Mice
Prolonged exposure to glucocorticoids (GCs) causes various metabolic derangements. These include obesity and insulin resistance, as inhibiting glucose utilization in adipose tissues is a major function of GCs. Although adipose tissue distribution and glucose homeostasis are sexdependently regulated, it has not been evaluated whether GCs affect glucose metabolism and adipose tissue functions in a sex-dependent manner. In this study, high-dose corticosterone (rodent GC) treatment in C57BU6J mice resulted in nonfasting hyperglycemia in male mice only, whereas both sexes displayed hyperinsulinemia with normal fasting glucose levels, indicative of insulin resistance. Metabolic testing using stable isotope-labeled glucose techniques revealed a sex-specific corticosterone-driven glucose intolerance. Corticosterone treatment increased adipose tissue mass in both sexes, which was reflected by elevated serum leptin levels. However, female mice showed more metabolically protective adaptations of adipose tissues than did male mice, demonstrated by higher serum total and high-molecular-weight adiponectin levels, more hyperplastic morphological changes, and a stronger increase in mRNA expression of adipogenic differentiation markers. Subsequently, in vitro studies in 3T3-L1 (white) and T37i (brown) adipocytes suggest that the increased leptin and adiponectin levels were mainly driven by the elevated insulin levels. In summary, this study demonstrates that GC-induced insulin resistance is more severe in male mice than in female mice, which can be partially explained by a sex-dependent adaptation of adipose tissues.</p
Sex difference in thermal preference of adult mice does not depend on presence of the gonads
Background: The thermoneutral zone (TNZ) is a species-specific range of ambient temperature (T a), at which mammals can maintain a constant body temperature with the lowest metabolic rate. The TNZ for an adult mouse is between 26 and 34 °C. Interestingly, female mice prefer a higher T a than male mice although the underlying mechanism for this sex difference is unknown. Here, we tested whether gonadal hormones are dominant factors controlling temperature preference in male and female mice. Methods: We performed a temperature preference test in which 10-week-old gonadectomized and sham-operated male and female C57BL/6J mice were allowed to choose to reside at the thermoneutral cage of 29 °C or an experimental cage of 26, 29, or 32 °C. Results: All mice preferred a T a higher than 26 °C, especially in the inactive phase. Choosing between 29 and 32 °C, female mice resided more at 32 °C while male mice had no preference between the temperatures. Hence, the preferred T a for female mice was significantly higher (0.9 ± 0.2 °C) than that for male mice. However, gonadectomy did not
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