Angiotensin II Signal Transduction: An Update on Mechanisms of Physiology and Pathophysiology

Abstract

The renin-angiotensin-aldosterone system plays crucial roles in cardiovascular physiology and pathophysiology. However, many of the signaling mechanisms have been unclear. The angiotensin II (ANG II) type 1 receptor (ATR) is believed to mediate most functions of ANG II in the system. ATR utilizes various signal transduction cascades causing hypertension, cardiovascular remodeling, and end organ damage. Moreover, functional cross-talk between ATR signaling pathways and other signaling pathways have been recognized. Accumulating evidence reveals the complexity of ANG II signal transduction in pathophysiology of the vasculature, heart, kidney, and brain, as well as several pathophysiological features, including inflammation, metabolic dysfunction, and aging. In this review, we provide a comprehensive update of the ANG II receptor signaling events and their functional significances for potential translation into therapeutic strategies. ATR remains central to the system in mediating physiological and pathophysiological functions of ANG II, and participation of specific signaling pathways becomes much clearer. There are still certain limitations and many controversies, and several noteworthy new concepts require further support. However, it is expected that rigorous translational research of the ANG II signaling pathways including those in large animals and humans will contribute to establishing effective new therapies against various diseases.

Clinical and biochemical indexes from 2019-nCoV infected patients linked to viral loads and lung injury

“…A recent article studied the 2019-nCoV genome sequence and predicted that the new coronavirus shared the ACE2 receptor of SARS-CoV , which is a critical enzyme in the renin-angiotensin system (RAS) (Huang et al, 2014;Zou et al, 2014). RAS plays important roles in maintaining blood pressure homeostasis (Forrester et al, 2018), and salt and fluid balance (Lin et al, 2017). ACE and ACE2 play different roles in RAS; ACE generates Angiotensin II, whereas ACE2 is a negative regulator of the system, decreasing Angiotensin II (Crackower et al 2002).…”

Angiotensin receptor subtypes regulate adipose tissue renewal and remodelling

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