TY - JOUR
T1 - Endothelin-1 activation of JAK2 in vascular smooth muscle cells involves NAD(P)H oxidase-derived reactive oxygen species
AU - Banes-Berceli, Amy K.L.
AU - Ogbi, Safia
AU - Tawfik, Amany
AU - Patel, Bela
AU - Shirley, Amanda
AU - Pollock, David M.
AU - Fulton, David
AU - Marrero, Mario B.
N1 - Funding Information:
This work was supported by and American Heart Association Scientist Development Grant (AKLB) and by National Institutes of Health Grants HL58139, DK50268 (MBM).
PY - 2005/11
Y1 - 2005/11
N2 - Endothelin-1 (ET-1) and JAK2 are both implicated in diabetic complications. Therefore, we investigated whether ET-1 differentially actives JAK2 under conditions of normal (5 mM) and high (25 mM) glucose. We tested the hypothesis that reactive oxygen species mediate the activation of JAK2 in response to ET-1. In rat aortic vascular smooth muscle cells (VSMC), ET-1 (10-7 M, 5 min) stimulated the activation of JAK2, which was further enhanced under high glucose conditions. Allopurinol (xanthine oxidase inhibitor, 1 μM) and l-NAME (nitric oxide synthase inhibitor, 1 mM) had no effect on ET-1-induced JAK2 activation, while apocynin (NAD(P)H oxidase inhibitor 100 μM) resulted in a significant inhibition of ET-1-induced JAK2 and MAPK activation. Overexpression of SOD did not inhibit ET-1-induced activation of JAK2, but catalase (50 units/mL) treatment resulted in complete inhibition. In vivo administration of apocynin (1.5 mM) resulted in a significant decrease (∼ 50%), while the ETA receptor antagonist ABT-627 completely inhibited phosphorylation of JAK2 in aortae from STZ-induced diabetic rats. Additionally, DHE staining of aortic sections was significantly reduced in diabetic rats treated with ABT-627. These data suggest that in VSMC, ET-1 via the ETA receptor, utilizes NAD(P)H oxidase to activate JAK2.
AB - Endothelin-1 (ET-1) and JAK2 are both implicated in diabetic complications. Therefore, we investigated whether ET-1 differentially actives JAK2 under conditions of normal (5 mM) and high (25 mM) glucose. We tested the hypothesis that reactive oxygen species mediate the activation of JAK2 in response to ET-1. In rat aortic vascular smooth muscle cells (VSMC), ET-1 (10-7 M, 5 min) stimulated the activation of JAK2, which was further enhanced under high glucose conditions. Allopurinol (xanthine oxidase inhibitor, 1 μM) and l-NAME (nitric oxide synthase inhibitor, 1 mM) had no effect on ET-1-induced JAK2 activation, while apocynin (NAD(P)H oxidase inhibitor 100 μM) resulted in a significant inhibition of ET-1-induced JAK2 and MAPK activation. Overexpression of SOD did not inhibit ET-1-induced activation of JAK2, but catalase (50 units/mL) treatment resulted in complete inhibition. In vivo administration of apocynin (1.5 mM) resulted in a significant decrease (∼ 50%), while the ETA receptor antagonist ABT-627 completely inhibited phosphorylation of JAK2 in aortae from STZ-induced diabetic rats. Additionally, DHE staining of aortic sections was significantly reduced in diabetic rats treated with ABT-627. These data suggest that in VSMC, ET-1 via the ETA receptor, utilizes NAD(P)H oxidase to activate JAK2.
KW - Diabetes
KW - Endothelin-1
KW - Reactive oxygen species
KW - Vascular smooth muscle cells
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U2 - 10.1016/j.vph.2005.08.024
DO - 10.1016/j.vph.2005.08.024
M3 - Article
C2 - 16290054
AN - SCOPUS:27744481080
SN - 1537-1891
VL - 43
SP - 310
EP - 319
JO - Vascular Pharmacology
JF - Vascular Pharmacology
IS - 5
ER -
