ANTIMÜLLERIAN HORMONE AS INDICATOR OF OVARIAN DYSFUNCTION

Anti-Müllerian hormone: biology and role in endocrinology and cancers

Anti-Müllerian hormone (AMH) is a peptide belonging to the transforming growth factor beta superfamily and acts exclusively through its receptor type 2 (AMHR2). From the 8th week of pregnancy, AMH is produced by Sertoli cells, and from the 23rd week of gestation, it is produced by granulosa cells of the ovary. AMH plays a critical role in regulating gonadotropin secretion, ovarian tissue responsiveness to pituitary hormones, and the pathogenesis of polycystic ovarian syndrome. It inhibits the transition from primordial to primary follicles and is considered the best marker of ovarian reserve. Therefore, measuring AMH concentration of the hormone is valuable in managing assisted reproductive technologies. AMH was initially discovered through its role in the degeneration of Müllerian ducts in male fetuses. However, due to its ability to inhibit the cell cycle and induce apoptosis, it has also garnered interest in oncology. For example, antibodies targeting AMHR2 are being investigated for their potential in diagnosing and treating various cancers. Additionally, AMH is present in motor neurons and functions as a protective and growth factor. Consequently, it is involved in learning and memory processes and may support the treatment of Alzheimer's disease. This review aims to provide a comprehensive overview of the biology of AMH and its role in both endocrinology and oncology.

Investigation of common risk factors between polycystic ovary syndrome and Alzheimer's disease: a narrative review

BACKGROUND

The most common endocrine and metabolic disorders in premenopausal women is polycystic ovary syndrome (PCOS), characterized by hyperandrogenism, chronic anovulation, and/or ultrasound evidence of small ovarian cysts. Obesity and insulin resistance are also the main factors influencing the clinical manifestations of this syndrome. Alzheimer's disease (AD) is the most typical progressive neurodegenerative disorder of the brain, and recent studies suggest a relationship between endocrinal dysregulation and neuronal loss during AD pathology.

AIM

This study aimed to evaluate the common risk factors for Alzheimer's and PCOS based on previous studies. Knowing the common risk factors and eliminating them may prevent neurodegenerative Alzheimer's disease in the future.

METHOD

In this narrative review, international databases, including Google Scholar, Scopus, PubMed, and the Web of Science, were searched to retrieve the relevant studies. The relevant studies' summaries were categorized to discuss the possible pathways that may explain the association between Alzheimer's and PCOS signs/symptoms and complications.

RESULTS

According to our research, the factors involved in Alzheimer's and PCOS disorders may share some common risk factors. In patients with PCOS, increased LH to FSH ratio, decreased vitamin D, insulin resistance, and obesity are some of the most important factors that may increase the risk of Alzheimer's disease.

Subfatin and asprosin, two new metabolic players of polycystic ovary syndrome

Asprosin and subfatin are recently discovered two new hormones of adipocyte origin that play a role in the regulation of glucose metabolism. Polycystic ovary syndrome (PCOS) is a gynaecological syndrome presenting with energy turbulence. The aim of this study was to investigate whether asprosin and subfatin play a role in PCOS disease. Thirty participants with a diagnosis of PCOS and thirty control group participants were included in this case-control study. Hormone profiles of the participants (subfatin, asprosin, insulin, prolactin, thyroid-stimulating hormone (TSH), oestradiol (E2), follicle-stimulating hormone (FSH), luteinising hormone (LH), dehydroepiandrosterone sulphate (DHEA-SO₄), lipid profiles [(total testosterone, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglyceride, cholesterol)], fasting blood sugar (FBS) and high-sensitivity C-reactive protein (hs-CRP) values were measured. While the levels of asprosin, LDL and triglyceride, TSH, E2, FSH, LH, DHEA-SO₄ were found to be significantly higher in patients with PCOS compared to controls (p = .005; p = .01), subfatin and HDL levels were found to be low. Significantly decreasing subfatin and increasing asprosin levels in circulation in PCOS may play a role in the etiopathology of this disease and that they may also be new candidate molecules in addition to classical laboratory parameters in the diagnosis and follow-up of PCOS in the future.Impact statementWhat is already known on this subject? The studies investigating the relationship between PCOS and asprosin are contradictory. Although subfatin has been studied in many metabolic diseases, it has not been studied yet whether it is associated with PCOS. Furthermore, whether there is a mutual relationship between subfatin and asprosin in patients with PCOS has not been studied yet.What do the results of this study add? This available data indicates that significantly decreasing subfatin and increasing asprosin levels in the circulation in PCOS may play a role in the etiopathology of this disease.What are the implications of these findings for clinical practice and/or further research? The findings are promising in that decreasing subfatin and increasing asprosin levels will shed new light on reproductive endocrinology changes caused by PCOS and may help to clarify the pathophysiology of PCOS. Furthermore, in our study, the asprosin/subfatin ratio was above three in PCOS disease. This ratio reported here is anticipated to contribute to the course or follow-up of the disease in the future. Also, subfatin has been investigated here for the first time, may also be a new candidate molecule in addition to classical laboratory parameters in the diagnosis and follow-up of PCOS.

Expression of genes that regulate follicle development and maturation during ovarian stimulation in poor responders

RESEARCH QUESTION

Sex hormone-binding globulin (SHBG), androgen receptor (AR), LH beta polypeptide (LHB), progesterone receptor membrane component 1 (PGRMC1) and progesterone receptor membrane component 2 (PGRMC2) regulate follicle development and maturation. Their mRNA expression was assessed in peripheral blood mononuclear cells (PBMC) of normal and poor responders, during ovarian stimulation.

DESIGN

Fifty-two normal responders and 15 poor responders according to the Bologna criteria were enrolled for IVF and intracytoplasmic sperm injection and stimulated with 200 IU of follitrophin alpha and gonadotrophin-releasing hormone antagonist. HCG was administered for final oocyte maturation. On days 1, 6 and 10 of stimulation, blood samples were obtained, serum hormone levels were measured, RNA was extracted from PBMC and real-time polymerase chain reaction was carried out to identify the mRNA levels. Relative mRNA expression of each gene was calculated by the comparative 2^-DDCt method.

RESULTS

Differences between mRNA levels of each gene on the same time point between the two groups were not significant. PGRMC1 and PGRMC2 mRNA levels were downregulated, adjusted for ovarian response and age. Positive correlations between PGRMC1 and AR (standardized beta = 0.890, P < 0.001) from day 1 to 6 and PGRMC1 and LHB (standardized beta = 0.806, P < 0.001) from day 1 to 10 were found in poor responders. PGRMC1 and PGRMC2 were positively correlated on days 6 and 10 in normal responders.

CONCLUSIONS

PGRMC1 and PGRMC2 mRNA are significantly decreased during ovarian stimulation, with some potential differences between normal and poor responders.