Abstract:

Growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis not only participates in body growth and development as well as energy homeostasis maintenance, but also plays a significant role in the regulation of male reproductive function. At the central level, IGF-1 can participate in the regulation of gonadotropin-releasing hormone and luteinizing hormone secretion through influencing the excitability of hypothalamic Kisspeptin/neurokinin B/dynorphin (KNDy) neurons. At the testicular level, the GH/IGF-1 axis can affect testosterone synthesis and spermatogenesis by regulating the functions of Leydig cells and Sertoli cells, enhancing the responsiveness of testis to gonadotropin, and improving the local microenvironment of spermatogenesis. At the peripheral effect level, GH/IGF-1 axis may participate in the regulation of erectile function by maintaining endothelial cell function, regulating the nitric oxide/cyclic guanosine monophosphate (NO/cGMP) signal pathway, supporting nerve repair and maintaining the stability of the smooth muscle of the corpus cavernosum. However, the existing evidence is mainly based on animal experiments, in vitro studies and small-sample clinical observations, and the impact of the GH/IGF-1 axis on male reproductive functions is not a one-way promotion. There is still a lack of high-quality clinical intervention studies to support its routine application.

Key words: Growth hormone, Insulin-like growth factor Ⅰ, Infertility, male, Pituitary hormones, Erectile dysfunction