Angiotensin-(1-7) relieved renal injury induced by chronic intermittent hypoxia in rats by reducing inflammation, oxidative stress and fibrosis.

Abstract

We aimed to study the renal injury and hypertension induced by chronic intermittent hypoxia (CIH) and the protective effects mediated by angiotensin 1-7 [Ang(1-7)]. We randomly assigned 32 male Sprague-Dawley rats (body weight 180-200 g) to normoxia control, CIH, Ang(1-7)-treated normoxia, and Ang(1-7)-treated CIH groups. Systolic blood pressure (SBP) was monitored at the start and end of each week. Renal sympathetic nerve activity (RSNA) was recorded. CTGF and TGF-β were detected by immunohistochemistry and western blotting. Tissue parameters of oxidative stress were also determined. In addition, renal levels of interleukin-6, tumor necrosis factor-α, nitrotyrosine, and hypoxia-inducible factor-1α were determined by immunohistochemistry, immunoblotting, and ELISA. TUNEL assay results and cleaved caspase 3 and 12 were also determined. Ang(1-7) induced a reduction in SBP together with a restoration of RSNA in the rat model of CIH. Ang(1-7) treatment also suppressed the production of reactive oxygen species, reduced renal tissue inflammation, ameliorated mesangial expansion, and decreased renal fibrosis. Thus, Ang(1-7) treatment exerted renoprotective effects on CIH-induced renal injury and was associated with a reduction of oxidative stress, inflammation and fibrosis. Ang(1-7) might therefore represent a promising therapy for obstructive sleep apnea-related hypertension and renal injury.

• Authors: W Lu, J Kang, K Hu, S Tang, X Zhou, S Yu, L Xu
• Journal: Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas (Braz J Med Biol Res) Vol. 50 Issue 1 Pg. e5594 (Jan 09 2017) ISSN: 1414-431X [Electronic] Brazil
• PMID: 28076452 (Publication Type: Journal Article)

Chemical References

• IL6 protein, human
• Interleukin-6
• Peptide Fragments
• Angiotensin I
• angiotensin I (1-7)

Topics

• Acute Kidney Injury (drug therapy)
• Angiotensin I (administration & dosage)
• Animals
• Disease Models, Animal
• Inflammation (drug therapy)
• Interleukin-6 (metabolism)
• Kidney (metabolism, pathology)
• Male
• Oxidative Stress (drug effects)
• Peptide Fragments (administration & dosage)
• Rats
• Rats, Sprague-Dawley