Regulation of Aldosterone Signaling by MicroRNAs

The mineralocorticoid hormone aldosterone is released by the adrenal glands in a homeostatic mechanism to regulate blood volume. Several cues elicit aldosterone release, and the long-term action of the hormone is to restore blood pressure and/or increase the retrieval of sodium from filtered plasma in the kidney. While the signaling cascade that results in aldosterone release is well studied, the impact of this hormone on tissues and cells in various organ systems is pleotropic. Emerging evidence indicates aldosterone may alter non-coding RNAs (ncRNAs) to integrate the hormonal response, and these ncRNAs may contribute to the heterogeneity of signaling outcomes in aldosterone target tissues. The best studied of the ncRNAs in aldosterone action are the small ncRNAs, microRNAs. MicroRNA expression is regulated by aldosterone stimulation, and microRNAs are able to modulate protein expression at all steps in the renin-angiotensin-aldosterone-signaling system. The discovery and synthesis of microRNAs will be briefly covered followed by a discussion of the reciprocal role of aldosterone/microRNA regulation, including misregulation of microRNA signaling in aldosterone-linked disease states.