Comparative expression analysis of the renin–angiotensin system components between white and brown perivascular adipose tissue

Abstract

Recent studies have demonstrated that the rat adipose tissue expresses some of the components necessary for the production of angiotensin II (Ang II) and the receptors mediating its actions. The aim of this work is to characterize the expression of the renin-angiotensin system (RAS) components in perivascular adipose tissue and to assess differences in the expression pattern depending on the vascular bed and type of adipose tissue. We analyzed Ang I and Ang II levels as well as mRNA levels of RAS components by a quantitative RT-PCR method in periaortic (PAT) and mesenteric adipose tissue (MAT) of 3-month-old male Wistar-Kyoto rats. PAT was identified as brown adipose tissue expressing uncoupling protein-1 (UCP-1). It had smaller adipocytes than those from MAT, which was identified as white adipose tissue. All RAS components, except renin, were detected in both PAT and MAT. Levels of expression of angiotensinogen, Ang-converting enzyme (ACE), and ACE2 were similar between PAT and MAT. Renin receptor expression was five times higher, whereas expression of chymase, AT 1a , and AT 2 receptors were significantly lower in PAT compared with MAT respectively. In addition, three isoforms of the AT 1a receptor were found in perivascular adipose tissue. The AT 1b receptor was found at very a low expression level. Ang II levels were higher in MAT with no differences between tissues in Ang I. The results show that the RAS is differentially expressed in white and brown perivascular adipose tissues implicating a different role for the system depending on the vascular bed and the type of adipose tissue.

CYP3A5 Genotype-Phenotype Analysis in the Human Kidney Reveals a Strong Site-Specific Expression of CYP3A5 in the Proximal Tubule in Carriers of the CYP3A5*1 Allele

“…Correctness of genotyping results was confirmed by direct sequencing using the ABI Prism 3130 Genetic Analyzer (Applied Biosystems, Foster City, CA). After reverse transcription of total RNA (n ϭ 93 samples) using the First Strand cDNA Synthesis Kit (Fermentas GmbH, St. Leon-Rot, Germany), mRNA expression levels of genes of interest, i.e., CYP3A4 and CYP3A5, were quantified as reported previously (Gálvez-Prieto et al, 2008). Details of the primers and probes used for quantitative real-time polymerase chain reaction are summarized in Supplemental Table 1.…”

Periadventitial Adipose Tissue Promotes Endothelial Dysfunction via Oxidative Stress in Diet-Induced Obese C57Bl/6 Mice

“…PVAT, which surrounds most blood vessels, is now considered an active endocrine organ, generating and secreting a wide range of biological substances that critically influence vascular tone. 1 PVAT attenuates the contractile responses to a variety of agonists in isolated large arteries obtained from mice, rats and humans. 2- 6 The attenuation of vasoconstriction depends on the amount of physiological adipose tissue and is based on continuous release of adipose tissue-derived relaxing factors, which enhance vasodilatation via both endothelium-dependent and -independent mechanisms.…”

Adipose tissue and vascular phenotypic modulation by voluntary physical activity and dietary restriction in obese insulin-resistant OLETF rats

“…Given the growing appreciation for phenotypic and functional heterogeneity among AT depots, including visceral, subcutaneous, brown, and perivascular adipose tissue (16,17,42,48), we also reasoned that the extent of the effects of physical activity and diet restriction on AT inflammation would be AT depotspecific. Furthermore, we tested the hypothesis that reduced AT expression and secretion of cytokines caused by physical activity or dietary restriction would be accompanied by a less proatherogenic vascular phenotype and enhanced insulin-stimulated vascular relaxation.…”