Prashar Vikash, Arora Tania, Singh Randeep, Sharma Arti, Parkash Jyoti
Department of Zoology, School of Basic Sciences, Central University of Punjab, Ghudda, Bathinda, 151401, Punjab, India.
Department of Computational Sciences, School of Basic Sciences, Central University of Punjab, Ghudda, Bathinda, 151401, Punjab, India.
Reprod Sci. 2023 Mar;30(3):802-822. doi: 10.1007/s43032-022-01027-5. Epub 2022 Jul 7.
Highly sophisticated and synchronized interactions of various cells and hormonal signals are required to make organisms competent for reproduction. GnRH neurons act as a common pathway for multiple cues for the onset of puberty and attaining reproductive function. GnRH is not directly receptive to most of the signals required for the GnRH secretion during the various phases of the ovarian cycle. Kisspeptin neurons of the hypothalamus convey these signals required for the synchronized release of the GnRH. The steroid-sensitive anteroventral periventricular nucleus (AVPV) kisspeptin and arcuate nucleus (ARC) KNDy neurons convey steroid feedback during the reproductive cycle necessary for GnRH surge and pulse, respectively. AVPV region kisspeptin neurons also communicate with nNOS synthesizing neurons and suprachiasmatic nucleus (SCN) neurons to coordinate the process of the ovarian cycle. Neurokinin B (NKB) and dynorphin play roles in the GnRH pulse stimulation and inhibition, respectively. The loss of NKB and kisspeptin function results in the development of neuroendocrine disorders such as hypogonadotropic hypogonadism (HH) and infertility. Ca signaling is essential for GnRH pulse generation, which is propagated through gap junctions between astrocytes-KNDy and KNDy-KNDy neurons. Impaired functioning of KNDy neurons could develop the characteristics associated with polycystic ovarian syndrome (PCOS) in rodents. Kisspeptin-increased synthesis led to excessive secretion of the LH associated with PCOS. This review provides the latest insights and understanding into the role of the KNDy and AVPV/POA kisspeptin neurons in GnRH secretion and PCOS.
生物体要具备生殖能力，需要各种细胞和激素信号进行高度复杂且同步的相互作用。促性腺激素释放激素（GnRH）神经元是青春期启动和获得生殖功能的多种信号的共同通路。在卵巢周期的各个阶段，GnRH对GnRH分泌所需的大多数信号不具有直接感受性。下丘脑的 kisspeptin 神经元传递GnRH同步释放所需的这些信号。下丘脑腹前室旁核（AVPV）的类固醇敏感型 kisspeptin 神经元和弓状核（ARC）的KNDy神经元分别在生殖周期中传递GnRH激增和脉冲所需的类固醇反馈。AVPV区域的kisspeptin神经元还与合成一氧化氮合酶（nNOS）的神经元和视交叉上核（SCN）神经元进行通信，以协调卵巢周期的进程。神经激肽B（NKB）和强啡肽分别在GnRH脉冲刺激和抑制中发挥作用。NKB和kisspeptin功能丧失会导致神经内分泌疾病的发生，如低促性腺激素性性腺功能减退（HH）和不孕症。钙信号对于GnRH脉冲的产生至关重要，其通过星形胶质细胞-KNDy和KNDy-KNDy神经元之间的缝隙连接进行传递。KNDy神经元功能受损可能会使啮齿动物出现与多囊卵巢综合征（PCOS）相关的特征。Kisspeptin合成增加会导致与PCOS相关的促黄体生成素（LH）过度分泌。本综述提供了关于KNDy以及AVPV/视前区（POA）kisspeptin神经元在GnRH分泌和PCOS中作用的最新见解和认识。
