PERSONAL DE APOYO
CACCIAMANI Valeria
congresos y reuniones científicas
Título:
Effect of Losartan on Caveolin-1 and Hsp70 Expression in Vascular Smooth Muscle Cells (VSMC) From Spontaneously Hypertensive Rats
Autor/es:
GIL LORENZO ANDREA; CACCIAMANI VALERIA; BENARDON MARÍA EUGENIA; LOPEZ APPIOLAZZA MARTÍN; GARRAMUÑO VALLÉS, PATRICIA
Lugar:
La Punta, San Luis
Reunión:
Congreso; XXVII Reunión Científica Anual Sociedad de Biología de Cuyo; 2009
Institución organizadora:
Sociedad de Biología de Cuyo
Resumen:
79.
EFFECT OF LOSARTAN ON CAVEOLIN-1 AND Hsp70
EXPRESSION IN VASCULAR SMOOTH MUSCLE CELLS
(VSMC) FROM SPONTANEOUSLY HYPERTENSIVE RATS
Gil Lorenzo AF, Cacciamani V, Benardon ME, Lopez Apiazzola M,
Vallés P.
IMBECU, CONICET, FCM, UNCuyo, Mendoza, 5500. E-mail:
gil.andrea@fcm.uncu.edu.ar
Full expression of Angiotensin II signaling in VSMCs is dependent
on the ROS derived from NADPH oxidase and the dynamic
association of the Ang II (Ang II) type I receptor (AT1
R) with
caveolae/lipid rafts.The chaperone Hsp70 regulates a diverse set
of signaling pathways through their interactions with proteins. We
examined the AT1
receptor antagonist Losartan effect, on Caveolin-
1 and Hsp70 protein and its involvement on oxidative stress in
VSMCs from SHR and WKY rats. VSMCs stimulated with Ang II
(100 μmol/L) for 15 min in the presence or absence of Losartan
(100 μmol/L) added 30 min before Ang II stimulation were subjected
to RT-PCR and Western blot analysis. The exposure of SHR
VSMCs to Ang II for 15 minutes downregulated membrane caveolin
expression and overexpressed p22 and Nox4 NADHP oxidase
isoforms, whereas Losartan increased Cav-1 expression, lightly
increased Hsp70 and decreased p22 and Nox4 protein levels in SHR
VSM cell membranes. VSMCs from WKY rats pretreated with
Losartan 100 μmol/L and subsequently stimulated with Ang II (100
μmol/L) for 15 minutes decreased NADHP isoforms p22 and Nox4,
and increased Hsp70 expression in cell membrane. Furthermore,
Losartan abolished the phosphorylation of ERK1/2 that was induced
by Ang II in SHR VSM cells. These findings suggest that
after Losartan administration, translocation of Hsp70 to VSM cell
membranes might exert a cytoprotective effect on oxidative stress.