The roles and mechanisms of Leydig cells and myoid cells in regulating spermatogenesis

Abstract

Spermatogenesis is fundamental to the establishment and maintenance of male reproduction, whereas its abnormality results in male infertility. Somatic cells, including Leydig cells, myoid cells, and Sertoli cells, constitute the microenvironment or the niche of testis, which is essential for regulating normal spermatogenesis. Leydig cells are an important component of the testicular stroma, while peritubular myoid cells are one of the major cell types of seminiferous tubules. Here we addressed the roles and mechanisms of Leydig cells and myoid cells in the regulation of spermatogenesis. Specifically, we summarized the biological features of Leydig cells and peritubular myoid cells, and we introduced the process of testosterone production and its major regulation. We also discussed other hormones, cytokines, growth factors, transcription factors and receptors associated with Leydig cells and myoid cells in mediating spermatogenesis. Furthermore, we highlighted the issues that are worthy of further studies in the regulation of spermatogenesis by Leydig cells and peritubular myoid cells. This review would provide novel insights into molecular mechanisms of the somatic cells in controlling spermatogenesis, and it could offer new targets for developing therapeutic approaches of male infertility.

Keywords: Cytokines; Growth factors; Hormones; Leydig cells; Myoid cells; Receptors; Spermatogenesis; Transcription factors.

Fig. 1

The factors derived from Leydig cells and myoid cells in regulating spermatogenesis. The diagram illustrates Leydig cells, myoid cells, Sertoli cells, and male germ cells in the testis, as well as the regulation of hormones, cytokines, growth factors, and receptors from Leydig cells and myoid cells in male germ cells

Fig. 2

The interactions of factors from Leydig cells, peritubular myoid cells and Sertoli cells in controlling spermatogenesis. Question marks indicated unknown