Prevention of adipose tissue depletion during food deprivation in angiotensin type 2 receptor-deficient mice

L Yvan-Charvet, P Even, N Lamandé, P Ferré… - …, 2006 - academic.oup.com
L Yvan-Charvet, P Even, N Lamandé, P Ferré, A Quignard-Boulangé
Endocrinology, 2006academic.oup.com
Angiotensin (Ang) II is produced locally in various tissues, but its role in the regulation of
tissue metabolism is still unclear. Recent studies have revealed the role of type 2 Ang II
receptor (AT2 R) in the control of energy homeostasis and lipid metabolism. The contribution
of the AT2 R to adaptation to starvation was tested using AT2 R-deficient (AT2 R y/−) mice.
Fasted AT2 R y/− mice exhibited a lower loss of adipose tissue weight associated to a
decreased free fatty acid (FFA) release from stored lipids than the controls. In vitro studies …
Angiotensin (Ang) II is produced locally in various tissues, but its role in the regulation of tissue metabolism is still unclear. Recent studies have revealed the role of type 2 Ang II receptor (AT2R) in the control of energy homeostasis and lipid metabolism. The contribution of the AT2R to adaptation to starvation was tested using AT2R-deficient (AT2Ry/−) mice. Fasted AT2Ry/− mice exhibited a lower loss of adipose tissue weight associated to a decreased free fatty acid (FFA) release from stored lipids than the controls. In vitro studies show that Ang II causes an AT1R-mediated antilipolytic effect in isolated adipocytes. AT1R expression is up-regulated by fasting in both genotypes, but the increase is more pronounced in AT2Ry/− mice. In addition, the increased muscle β-oxidation displayed in AT2Ry/− mice on a fed state, persists after fasting compared with wild-type mice. In liver from fed mice, AT2R deficiency did not modify the expression of genes involved in fatty acid oxidation. However, in response to fasting, the large increase of the expression of this subset of genes exhibited by wild-type mice, was impaired in AT2Ry/− mice. Taken together, decreased lipolytic capacity and increased muscle fatty acid oxidation participate in the decreased plasma FFA observed in fasted AT2Ry/− mice and could account for the lower FFA metabolism in the liver. These data reveal an important physiological role of AT2R in metabolic adaptations to fasting.
Oxford University Press