Angiotensin II blockade: how its molecular targets may signal to mitochondria and slow aging. Coincidences with calorie restriction and mTOR inhibition

Abstract

de Cavanagh EM, Inserra F, Ferder L. Angiotensin II blockade: how its molecular targets may signal to mitochondria and slow aging. Coincidences with calorie restriction and mTOR inhibition. Am J Physiol Heart Circ Physiol 309: H15-H44, 2015. First published May 1, 2015; doi:10.1152/ajpheart.00459.2014, renin angiotensin system blockade (RAS-bl), and rapamycin-mediated mechanistic target of rapamycin (mTOR) inhibition increase survival and retard aging across species. Previously, we have summarized CR and RAS-bl's converging effects, and the mitochondrial function changes associated with their physiological benefits. mTOR inhibition and enhanced sirtuin and KLOTHO signaling contribute to the benefits of CR in aging. mTORC1/mTORC2 complexes contribute to cell growth and metabolic regulation. Prolonged mTORC1 activation may lead to age-related disease progression; thus, rapamycin-mediated mTOR inhibition and CR may extend lifespan and retard aging through mTORC1 interference. Sirtuins by deacetylating histone and transcription-related proteins modulate signaling and survival pathways and mitochondrial functioning. CR regulates several mammalian sirtuins favoring their role in aging regulation. KLOTHO/fibroblast growth factor 23 (FGF23) contribute to control Ca 2ϩ , phosphate, and vitamin D metabolism, and their dysregulation may participate in age-related disease. Here we review how mTOR inhibition extends lifespan, how KLOTHO functions as an aging suppressor, how sirtuins mediate longevity, how vitamin D loss may contribute to age-related disease, and how they relate to mitochondrial function. Also, we discuss how RAS-bl downregulates mTOR and upregulates KLOTHO, sirtuin, and vitamin D receptor expression, suggesting that at least some of RAS-bl benefits in aging are mediated through the modulation of mTOR, KLOTHO, and sirtuin expression and vitamin D signaling, paralleling CR actions in age retardation. Concluding, the available evidence endorses the idea that RAS-bl is among the interventions that may turn out to provide relief to the spreading issue of age-associated chronic disease. mechanistic target of rapamycin; vitamin D; caloric restriction; renin-angiotensin system EFFORTS AIMED AT DECIPHERING the mechanisms that underlie the aging process have unveiled three interventions that can increase survival and retard age-related diseases from lower organisms to mammals, i.e., caloric restriction (CR) (84,85,140,160,334), mechanistic target of rapamycin (mTOR; originally mammalian TOR) inhibition by rapamycin (173,196,281), and renin-angiotensin system blockade (RAS-bl) (20, 21, 26,63,253,284,354), although the latter has been less studied. In light of these findings, some intriguing questions come to mind: Do these interventions attenuate aging by interfering with common mechanisms? Do the mechanisms that are interfered with by CR, rapamycin, and RAS-bl mutually affect each other? Are there any pathways involved exclusively with a certain intervention?Previously (101), we have discussed the converging effects d...

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“…140 As previously described, cytokines and Ang II are strong inducers of cellular senescence. 4 Notably, Ang II is a neurohumoral factor that is closely related to cellular senescence and provokes cytokine production in cardiomyocytes, which could synergistically induce a phenotypic alteration associated with aging. 3 For instance, isolated adult cardiomyocytes prepared from a hypertrophied heart of a rat by pressure overload secrete TNFα, IL-1β, and IL-6 after Ang II administration.…”

“…Herein, we define aging and senescence as a decline in normal physiological functioning, including the robustness and flexibility observed in mature organisms over time. In general, it is thought that proinflammatory cytokines and neurohumoral factors, such as angiotensin II (Ang II), are involved in senescence progression, ie, a decline in physiological functioning caused by aging, 3,4 and multiple signaling pathways play dominant roles in the aging process. At the cellular level, aging and senescence represent the declining cellular capacity for proliferation or regeneration.…”