ACTUALITIES IN MUTATIONS OF LUTEINIZING HORMONE (LH) AND FOLLICLE-STIMULATING HORMONE (FSH) RECEPTORS

Mechanisms and rescue measures of female ovarian dysfunction induced by environmental endocrine chemicals: A review

Environmental endocrine chemicals (EDCs) constitute a class of exogenous chemicals with the capacity to imitate or impede the processes of synthesis, secretion, transport, conjugation, reaction, and metabolism of natural hormones in living organisms. They elicit a broad spectrum of physiological effects, which may either mirror those of natural hormones or exhibit anti-natural characteristics. Prolonged exposure to EDCs has been demonstrated to exert significant effects on animal reproduction and development. It is noteworthy that the female reproductive system is more susceptible to the effects of EDCs than the male reproductive system. EDCs have the potential to cause significant damage to the structure and function of the female reproductive organs, and have been linked to an increased incidence of various tumors in the female reproductive system, including ovarian cancer. A growing body of evidence suggests that exposure to EDCs affects reproduction in five main ways: competitively binding to cell membrane-specific receptors, disruption of cellular signaling within germ cells, intracellular imbalance between reactive oxygen species and antioxidants, alteration of epigenetic modifications, and control of early apoptosis. Nevertheless, the same in vivo and in vitro studies have indicated that the reproductive toxicity produced by EDCs can also be attenuated in a multitude of ways, such as by antioxidants, hormones, and compensatory mechanisms of signal transduction. Through comprehensive analysis of epidemiological studies, laboratory experiments, and clinical observations, this review details the mechanisms of the effects of EDCs leading to ovarian dysfunction and proposes a series of strategies to prevent EDCs exposure.

Luteinizing Hormone Induces Murine Hair Loss through Transient Receptor Potential Canonical Channel-Mediated Cell Aging Responses: Implications for Female Pattern Hair Loss Pathogenesis

Menopause-related hormonal imbalances, particularly the decline in estrogen and the rise in luteinizing hormone (LH), are implicated in female-pattern hair loss (FPHL). This study investigated the role of LH in FPHL, because its precise function has remained unclear. Our results found a significant association between elevated LH levels and FPHL. The binding of LH to LH receptor activates downstream transient receptor potential canonical channels (TRPCs), which potentially mediate excess calcium ion signals to initiate cell-aging responses. We revealed that LH causes ROS accumulation, calcium ion elevation and senescence in vibrissa follicles, and cell damage through DNA damage response, senescence, and senescence-associated secretory phenotype activation in dermal papilla cells. Hair loss in mice was due to LH-induced hair follicle damage and aging. The involvement of TRPCs in LH-induced pathogenesis was examined by treatment with TRPC inhibitors. Similarly, the balding area of FPHL showed higher levels of LH receptor than the nonbalding area, whereas expressions of DNA damage response-related genes, senescence-associated secretory phenotype-related genes, and TRPCs were upregulated in scalp biopsies. Overall, we identified the impacts of LH/LH receptor signaling on the pathogenesis of FPHL, including TRPC-mediated cell-aging responses in hair follicles.

Follicle-stimulating hormone (FSH) receptor gene polymorphisms in Iraqi patients with non-obstructive azoospermia

Background: Follicle-stimulating hormone (FSH) is a pivotal hormone for male fertility, and its action on gonads is exerted by FSH receptors (FSHRs). Objectives: To examine whether the presence of FSHR gene single nucleotide polymorphisms (SNPs), G919A and A2039G, involved in non-obstructive azoospermia (NOA) in Iraqi infertile men. Methods: Two common SNPs, A919G and A2039G, in the FSHR gene were analyzed in 104 subjects (70 infertile patients with NOO: 33 NOA patients were not receiving treatment and 37 were on infertility treatment, and 34 normozoospermic fertile men as controls). Results: The results revealed that the homozygous wild genotype (AA) of rs6165 FSHR gene SNP was more abundant than (AG) and (GG) genotypes in both groups of infertile NOA patients with a frequency of 49% in those who untreated, 81% in patients undergoing treatment and in the control group 41%. Whereas, the highest percentage of heterozygous genotype (AG) in the fertile control group was 41% when compared to NOApatients with a genotype frequency of 24% (for those who untreated) and 11% (for patients on treatment), respectively; with (A) allele frequency of 86% and the observed frequency of (G) allele was only 14% in the patients’ group as compared to that of controls that were  (65 %) and (35 %), respectively. The rs6166 genotyping revealed that the homozygous wild genotype (GG) of FSHR gene was more abundant than (AG) and (AA) genotypes in NOA patients receiving infertility treatment with a frequency of (68%), in NOA patients who didn’t receive treatment 49%, while the lowest frequency was detected in the healthy fertile control group (47%). Conclusions: These results support the evidence that rs6165 and rs6166, FSHR SNPs, might be involved in the pathogenesis and protection against NOA, respectively.

Glycoprotein G-protein Coupled Receptors in Disease: Luteinizing Hormone Receptors and Follicle Stimulating Hormone Receptors

Signal transduction by luteinizing hormone receptors (LHRs) and follicle-stimulating hormone receptors (FSHRs) is essential for the successful reproduction of human beings. Both receptors and the thyroid-stimulating hormone receptor are members of a subset of G-protein coupled receptors (GPCRs) described as the glycoprotein hormone receptors. Their ligands, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) and a structurally related hormone produced in pregnancy, human chorionic gonadotropin (hCG), are large protein hormones that are extensively glycosylated. Although the primary physiologic functions of these receptors are in ovarian function and maintenance of pregnancy in human females and spermatogenesis in males, there are reports of LHRs or FSHRs involvement in disease processes both in the reproductive system and elsewhere. In this review, we evaluate the aggregation state of the structure of actively signaling LHRs or FSHRs, their functions in reproduction as well as summarizing disease processes related to receptor mutations affecting receptor function or expression in reproductive and non-reproductive tissues. We will also present novel strategies for either increasing or reducing the activity of LHRs signaling. Such approaches to modify signaling by glycoprotein receptors may prove advantageous in treating diseases relating to LHRs or FSHRs function in addition to furthering the identification of new strategies for modulating GPCR signaling.

FSH RECEPTOR AND FSH BETA CHAIN POLYMORPHISM INVOLVEMENT IN INFERTILITY AND ENDOMETRIOSIS DISEASE

OBJECTIVES

The purpose of this study was to evaluate the association between the follicle-stimulating hormone (FSH) receptor (c.-29G>A) and FSH beta chain (c.-280G>T) polymorphisms and endometriosis in Romanian women.

MATERIAL AND METHODS

We performed the polymorphic analysis of the FSH receptor gene and FSH beta chain in 44 patients with endometriosis and 34 controls. Genomic DNA was obtained from peripheral blood and polymorphisms were investigated using restriction fragment length polymorphism analysis (RFLP).

RESULTS

There were no significant differences in genotype frequencies of FSH receptor gene between endometriosis patients and controls. For the heterozygous type of the FSH receptor polymorphism (c.-29G>A) we did not find a significant difference in its frequency between patients with minimal/mild and moderate/severe endometriosis (p = 0.136). Also, the FSH beta chain (c.-280G> T) polymorphism frequency was not significantly associated with the severity of endometriosis (p = 0.966).

CONCLUSIONS

FSH receptor and FSH beta chain polymorphisms do not seem to influence the severity of endometriosis, but they could be correlated with female infertility (primary or secondary), therefore further studies are required to debate this topic.