TY - JOUR
T1 - Neurotrophins induce nitric oxide generation in human pulmonary artery endothelial cells
AU - Meuchel, Lucas W.
AU - Thompson, Michael A.
AU - Cassivi, Steven D.
AU - Pabelick, Christina M.
AU - Prakash, Y. S.
N1 - Funding Information:
This work was supported by the National Heart, Lung and Blood Institute of the National Institutes of Health (grant numbers HL088029, HL056470, HL09595), and by a Clinical Innovator Award from the Flight Attendants Medical Research Institute (FAMRI). L.W.M. is a graduate student and is supported by the Mayo Graduate School, Rochester, MN, USA. This paper represents partial satisfaction of his PhD thesis.
PY - 2011/9/1
Y1 - 2011/9/1
N2 - Aims Members of the growth factor family of neurotrophins [NTs; e.g. brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT3)] and their high-affinity receptors (tropomyosin-related kinase; Trk) and low-affinity receptors p75 neurotrophin receptor (p75NTR) have been localized to pulmonary artery (PA) in humans. However, their role is unclear. Based on previous findings of NTs and their receptors within the pulmonary endothelium, we tested the hypothesis that NTs induce nitric oxide (NO) production in pulmonary endothelial cells (ECs), thus contributing to vasodilation. Methods and resultsIn human pulmonary artery ECs loaded with the NO-sensitive fluorescent dye diaminofluorescein-2, both BDNF and NT3 (100 pM, 1 nM, and 10 nM) acutely (<10 min) and substantially increased fluorescence levels in a concentration-dependent fashion (to levels comparable to that induced by 1 μM acetylcholine). NT-induced elevation of NO levels was blunted by the tyrosine kinase inhibitor K252a, the nitric oxide synthase (NOS) inhibitor N GnitroLarginine methyl ester, the Ca 2 chelator 1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid, and the NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide. Suppression of TrkB or TrkC expression via siRNA as well as functional blockade of p75NTR prevented NT-induced NO elevation. Both BDNF and NT3 increased phosphorylation of Akt and endothelial NO synthase (eNOS). In endothelium-intact porcine PA rings, NTs increased cGMP and induced vasodilation in pre-contracted arteries. ConclusionThese results indicate that NTs acutely modulate pulmonary endothelial NO production and contribute to relaxation of the pulmonary vasculature.
AB - Aims Members of the growth factor family of neurotrophins [NTs; e.g. brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT3)] and their high-affinity receptors (tropomyosin-related kinase; Trk) and low-affinity receptors p75 neurotrophin receptor (p75NTR) have been localized to pulmonary artery (PA) in humans. However, their role is unclear. Based on previous findings of NTs and their receptors within the pulmonary endothelium, we tested the hypothesis that NTs induce nitric oxide (NO) production in pulmonary endothelial cells (ECs), thus contributing to vasodilation. Methods and resultsIn human pulmonary artery ECs loaded with the NO-sensitive fluorescent dye diaminofluorescein-2, both BDNF and NT3 (100 pM, 1 nM, and 10 nM) acutely (<10 min) and substantially increased fluorescence levels in a concentration-dependent fashion (to levels comparable to that induced by 1 μM acetylcholine). NT-induced elevation of NO levels was blunted by the tyrosine kinase inhibitor K252a, the nitric oxide synthase (NOS) inhibitor N GnitroLarginine methyl ester, the Ca 2 chelator 1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid, and the NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide. Suppression of TrkB or TrkC expression via siRNA as well as functional blockade of p75NTR prevented NT-induced NO elevation. Both BDNF and NT3 increased phosphorylation of Akt and endothelial NO synthase (eNOS). In endothelium-intact porcine PA rings, NTs increased cGMP and induced vasodilation in pre-contracted arteries. ConclusionThese results indicate that NTs acutely modulate pulmonary endothelial NO production and contribute to relaxation of the pulmonary vasculature.
KW - Brain-derived neurotrophic factor
KW - Lung
KW - Neurotrophin-3
KW - Tropomyosin-related kinase
KW - p75NTR
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U2 - 10.1093/cvr/cvr107
DO - 10.1093/cvr/cvr107
M3 - Article
C2 - 21498417
AN - SCOPUS:80051976998
SN - 0008-6363
VL - 91
SP - 668
EP - 676
JO - Cardiovascular research
JF - Cardiovascular research
IS - 4
ER -