Advanced search
Start date
Betweenand
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Renal Hemodynamic and Morphological Changes after 7 and 28 Days of Leptin Treatment: The Participation of Angiotensin II via the AT(1) Receptor

Full text
Author(s):
Thieme, Karina [1] ; Oliveira-Souza, Maria [1]
Total Authors: 2
Affiliation:
[1] Univ Sao Paulo, Inst Biomed Sci, Dept Physiol & Biophys, Sao Paulo - Brazil
Total Affiliations: 1
Document type: Journal article
Source: PLoS One; v. 10, n. 3 MAR 20 2015.
Web of Science Citations: 9
Abstract

The role of hyperleptinemia in cardiovascular diseases is well known; however, in the renal tissue, the exact site of leptin's action has not been established. This study was conducted to assess the effect of leptin treatment for 7 and 28 days on renal function and morphology and the participation of angiotensin II (Ang II), through its AT(1) receptor. Rats were divided into four groups: sham, losartan (10 mg/kg/day, s.c.), leptin (0.5 mg/kg/day for the 7 days group and 0.25 mg/kg/day for the 28 days group) and leptin plus losartan. Plasma leptin, Ang II and endothelin 1 (ET-1) levels were measured using an enzymatic immuno assay. The systolic blood pressure (SBP) was evaluated using the tail-cuff method. The renal plasma flow (RPF) and the glomerular filtration rate (GFR) were determined by p-aminohippuric acid and inulin clearance, respectively. Urinary Na+ and K+ levels were also analyzed. Renal morphological analyses, desmin and ED-1 immunostaining were performed. Proteinuria was analyzed by silver staining. mRNA expression of renin-angiotensin system (RAS) components, TNF-alpha and collagen type III was analyzed by quantitative PCR. Our results showed that leptin treatment increased Ang II plasma levels and progressively increased the SBP, achieving a pre-hypertension state. Rats treated with leptin 7 days showed a normal RPF and GFR, but increased filtration fraction (FF) and natriuresis. However, rats treated with leptin for 28 showed a decrease in the RPF, an increase in the FF and no changes in the GFR or tubular function. Leptin treatment-induced renal injury was demonstrated by: glomerular hypertrophy, increased desmin staining, macrophage infiltration in the renal tissue, TNF-a and collagen type III mRNA expression and proteinuria. In conclusion, our study demonstrated the progressive renal morphological changes in experimental hyperleptinemia and the interaction between leptin and the RAS on these effects. (AU)

FAPESP's process: 10/19656-5 - Structure and renal function in hypertension and experimental hyperleptinemia: role of renin-angiotensin-aldosterone system
Grantee:Maria Oliveira de Souza
Support type: Regular Research Grants
FAPESP's process: 13/23087-4 - Molecular and functional study of membrane transporters
Grantee:Gerhard Malnic
Support type: Research Projects - Thematic Grants
FAPESP's process: 13/19569-3 - Effects of endothelin-3 and leptin in renal morphology and function in vivo: involvement of the intrarenal renin-angiotensin system
Grantee:Maria Oliveira de Souza
Support type: Regular Research Grants
FAPESP's process: 08/58287-5 - Molecular and functional study of ion transporters in membranes
Grantee:Gerhard Malnic
Support type: Research Projects - Thematic Grants