Mutual Interactions Between GnRH and Kisspeptin in GnRH- and Kiss-1-Expressing Immortalized Hypothalamic Cell Models

KISS-1 knockdown inhibits cell growth, migration, and invasion in HTR-8/SVneo cells by regulating the GRP54-mediated PI3K/AKT signaling pathway

Recurrent spontaneous abortions (RSA) affect reproductive health and increase the risk of subsequent abortions. To investigate the role of KISS-1/GPR-54 signaling in RSA progression. Villus tissue was collected from RSA patients, and human trophoblastic HTR-8/SVneo cells were used. KISS-1 and GRP54 levels were detected using RT-qPCR and immunohistochemistry. Western blotting was performed to analyze ZO-1 and ZEB1 levels. Cell proliferation was determined via CCK-8 and cell clone formation assays. Transwell assays were performed to assess cell migration and invasion abilities. KISS-1 was down-regulated in the villus tissues of RSA patients. KISS-1 overexpression dramatically inhibited trophoblast proliferation, migration, and invasion. Mechanistically, ZEB1 expression was down-regulated, whereas ZO-1 expression was up-regulated, after KISS-1 overexpression. GPR54 silencing neutralized the effect of KISS-1 in HTR-8/SVneo cells. Additionally, KISS-1 overexpression inactivated the PI3K/AKT signaling pathway through GRP54. The KISS-1/GPR-54 signaling axis regulates RSA progression by regulating the PI3K/AKT signaling pathway.

Kisspeptin induces Kiss-1 and GnRH gene expression in mHypoA-55 hypothalamic cell models: Involvement of the ERK and PKA signaling pathways

mHypoA-55 cells are kisspeptin-expressing neuronal cells originating from the arcuate nucleus of the mouse hypothalamus. These cells are called KNDy neurons because they co-express kisspeptin, neurokinin B, and dynorphin A. In addition, they express gonadotropin-releasing hormone (GnRH). Here, we found that kisspeptin 10 (KP10) increased Kiss-1 (encoding kisspeptin) and GnRH gene expression in kisspeptin receptor (Kiss-1R)-overexpressing mHypoA-55 cells. KP10 greatly increased serum response element (SRE) promoter activity, which is a target of extracellular signal-regulated kinase (ERK) (20.0 ± 2.54-fold). KP10 also increased cAMP-response element (CRE) promoter activity in these cells (2.32 ± 0.36-fold). KP10-increased SRE promoter activity was significantly prevented in the presence of PD098095, a MEK kinase (MEKK) inhibitor, and KP10-induced CRE promoter activity was also inhibited by PD098059. Similarly, H89, a protein kinase A (PKA) inhibitor, significantly inhibited the KP10 induction of SRE and CRE promoters. KP10-induced Kiss-1 and GnRH gene expressions were inhibited in the presence of PD098059. Likewise, H89 significantly inhibited the KP10-induced increase in Kiss-1 and GnRH. Transfection of mHypoA-55 cells with constitutively active MEKK (pFC-MEKK) increased SRE and CRE promoter activities by 9.75 ± 1.77- and 1.36 ± 0.12-fold, respectively. Induction of constitutively active PKA (pFC-PKA) also increased SRE and CRE promoter activities by 2.41 ± 0.42- and 40.71 ± 7.77-fold, respectively. Furthermore, pFC-MEKK and -PKA transfection of mHypoA-55 cells increased both Kiss-1 and GnRH gene expression. Our current observations suggest that KP10 increases both the ERK and PKA pathways and that both pathways mutually interact in mHypoA-55 hypothalamic cells. Activation of both ERK and PKA signaling might be necessary to induce Kiss-1 and GnRH gene expressions.

Study of serum level of kisspeptin and interferon-beta in genital wart patients

Background

Researchers are interested in genital wart (GW) studies due to their increased incidence. In a single experimental research, virally infected mouse models showed elevated kisspeptin levels and low interferon levels.

Objective

The objective of the study was to evaluate the serum levels of kisspeptin and interferon (INF)-beta in GW patients.

Patients and Methods

Forty patients with GWs and forty healthy participants of comparable age and sex as a control group were included in this case-control study. Serum levels of kisspeptin and IFN-beta were measured using ELISA during the period from December 2021 to April 2022.

Results

Kisspeptin was significantly higher among cases than controls, whereas IFN-beta level was lower among cases than controls (P < 0.001). There were no significant relations between kisspeptin and IFN-beta levels and the clinical data for the studied participants, and there was no significant correlation between both (P > 0.05).

Conclusion

The reported increased kisspeptin level which was associated with decreased interferon-beta level in patients with GWs might indicate a new insight into viral infection pathogenesis. Further research including all steps in kisspeptin/G protein-coupled receptor 54 pathway is required. Targeted therapy for this pathway may be of value for those patients.

Putative Role of the Kisspeptin/Kiss1R System in Promoting Hypothalamic GnRH Release, Pubertal Maturation, and Regulation of Ovulation Considering the Central Reproductive Axis

Kisspeptin is a class of neuropeptides that are the product of the Kiss1 gene. These neuropeptides play an important role in maintaining gonadotropin-releasing hormone (GnRH) levels and their release through hypothalamic neurons. Subsequently, they also play an important role in maintaining gonadotropin levels, as GnRH levels stimulate the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which allow induction of gametogenesis of pubertal maturation. The importance of the Kiss1 gene in reproduction became evident when natural mutations in this gene were discovered, which were associated with hypothalamic hypogonadism (HH) and delayed puberty. Kisspeptin and its KISS1R receptors are expressed in the mammalian ovary. The putative role of the Kisspeptin system in the ovary directly controls oocyte maturation, follicular development, and ovulation in an autocrine and paracrine fashion. These essential facts of kisspeptin and its receptor are necessary to maintain the central reproductive axis.