Androgens are an important class of hormones that play a key role in regulating male sexual characteristics and reproductive development. They are responsible for the development of the external male genitalia, the deepening of the male voice, and the development of facial and body hair. In addition, androgens play a role in male secondary sexual characteristics such as increased muscle mass and strength, and the maintenance of bone density. In women, androgens are important regulators of libido, bone health, and metabolic rate.
Androgens are produced mainly in the testes of males and the ovaries of females, and to a lesser extent, in the adrenal glands. Testosterone is the most prominent androgen, and is responsible for the development of the primary male sex characteristics, such as the male external genitalia and the deepened male voice. In women, testosterone is produced in the ovaries and is responsible for libido, bone health, and metabolic rate.
Androgens are also known to influence various physiological processes, such as the regulation of body fat, muscle mass, and bone density. Androgens have also been linked to a variety of psychological processes, including mood, aggression, motivation, and cognitive functioning. Additionally, androgens have been shown to influence social behavior, such as social dominance and territoriality.
The effects of androgens on the body are mediated by two distinct pathways: the androgen receptor pathway and the non-receptor pathway. The androgen receptor pathway involves the binding of testosterone to the androgen receptor, which then activates a cascade of intracellular signaling pathways that ultimately lead to the physiological effects of androgens. The non-receptor pathway, also known as the non-genomic pathway, is less understood but involves the direct binding of testosterone to membrane proteins, such as G-protein coupled receptors, which then activate a cascade of intracellular signaling pathways.
Overall, androgens play an important role in the development and maintenance of male and female reproductive and sexual characteristics. Additionally, androgens have been linked to a variety of physiological and psychological processes, as well as social behavior.
References
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Meyer, A., & Payne, A.H. (2019). Androgens: Their role in physiology and pathology. Endocrine Reviews, 40(4), 639-676.
Nett, T.M., Heim, T., Oettel, M., & Saad, F. (2016). Androgen action in target tissues: Receptor-dependent and -independent pathways. Molecular and Cellular Endocrinology, 433(1-2), 68-76.
Travison, T.G., Araujo, A.B., O’Donnell, A.B., Kupelian, V., & McKinlay, J.B. (2007). A population-level decline in serum testosterone levels in American men. The Journal of Clinical Endocrinology & Metabolism, 92(1), 196-202.