Non-genomic actions of sex steroid hormones

• Published in: European journal of endocrinology Vol. 148; no. 3; pp. 281 - 292
• Main Authors: Simoncini, T, Genazzani, AR
• Format: Journal Article
• Language: English
• Published: Colchester European Society of Endocrinology 01.03.2003; Portland Press
• Subjects: Animals; Biological and medical sciences; Cell Membrane - physiology; Cell receptors; Cell structures and functions; Fundamental and applied biological sciences. Psychology; Gonadal Steroid Hormones - physiology; GTP-Binding Proteins - metabolism; Hormone receptors. Growth factor receptors. Cytokine receptors. Prostaglandin receptors; Humans; Ion Channels - metabolism; Molecular and cellular biology; Protein Kinases - physiology; s; Signal Transduction - physiology; Enzyme; Transferases; Central nervous system; Steroid hormone receptor; Ionic channel; Metabolic pathway; Biological activity; Signal transduction; Protein kinase; Plasma membrane; Hormonal regulation; Circulatory system; Sex steroid hormone; G protein
• ISSN: 0804-4643; 1479-683X
• DOI: 10.1530/eje.0.1480281

Steroid hormone receptors have been traditionally considered to act via the regulation of transcriptional processes, involving nuclear translocation and binding to specific response elements, and ultimately leading to regulation of gene expression. However, novel non-transcriptional mechanisms of signal transduction through steroid hormone receptors have been identified. These so-called 'non-genomic' effects do not depend on gene transcription or protein synthesis and involve steroid-induced modulation of cytoplasmic or cell membrane-bound regulatory proteins. Several relevant biological actions of steroids have been associated with this kind of signaling. Ubiquitous regulatory cascades such as mitogen-activated protein kinases, the phosphatidylinositol 3-OH kinase and tyrosine kinases are modulated through non-transcriptional mechanisms by steroid hormones. Furthermore, steroid hormone receptor modulation of cell membrane-associated molecules such as ion channels and G-protein-coupled receptors has been shown. TIssues traditionally considered as 'non-targets' for classical steroid actions are instead found to be vividly regulated by non-genomic mechanisms. To this aim, the cardiovascular and the central nervous system provide excellent examples, where steroid hormones induce rapid vasodilatation and neuronal survival via non-genomic mechanisms, leading to relevant pathophysiological consequences. The evidence collected in the past Years indicates that target cells and organs are regulated by a complex interplay of genomic and non-genomic signaling mechanisms of steroid hormones, and the integrated action of these machineries has important functional roles in a variety of pathophysiological processes. The understanding of the molecular basis of the rapid effects of steroids is therefore important, and may in the future turn out to be of relevance for clinical purposes.