TY - JOUR
T1 - Perinatal changes in superoxide generation in the ovine lung
T2 - Alterations associated with increased pulmonary blood flow
AU - Sharma, Shruti
AU - Kumar, Sanjiv
AU - Wiseman, Dean A.
AU - Kallarackal, Suphin
AU - Ponnala, Sumant
AU - Elgaish, Manal
AU - Tian, Jing
AU - Fineman, Jeffrey R.
AU - Black, Stephen M.
N1 - Funding Information:
This research was supported in part by grants HL60190 , HL6784 , HL84739 , HD57406 (all to SMB), HL61284 (to JRF) all from the National Institutes of Health , by a Transatlantic Network Development Grant from the Fondation LeDucq (to SMB & JRF), an AHA Southeast affiliates Beginning Grant In Aid Award ( 09BGIA2310050 , to SS), and Seed Awards (to SS and SK) from the Cardiovascular Discovery Institute at the Medical College of Georgia . DAW was supported in part by HL90198 .
PY - 2010/7
Y1 - 2010/7
N2 - Although alterations in ROS generating systems are well described in several vascular disorders, there is very limited information on the perinatal regulation of these systems in the lung both during normal development and in pulmonary hypertension. Thus, this study was undertaken to explore how the two predominant superoxide generating systems, nicotinamide adenine dinucleotide phosphate-oxidase (NADPH oxidase) and xanthine oxidase (XO), are developmentally regulated in control lambs and in our established lamb model of increased pulmonary blood flow (Shunt) over the first 2 months of life. We found that the levels of p47phox, p67phox, and Rac1 subunits of NADPH oxidase complex were altered. During the first two months of life there was no change in p47phox protein levels in either normal or Shunt lambs. However, both p67phox and Rac1 protein levels decreased over time. In addition, p47phox protein levels were significantly increased in shunt lambs at 2- and 4-, but not 8-weeks of age compared to age-matched controls while levels of the p67phox subunit were decreased at 8-weeks of age in the Shunts but unchanged at other time periods. Furthermore, Rac1 protein expression was significantly increased in the Shunts only at 4 weeks of age. These data correlated with a significant increase in NADPH oxidase dependent superoxide generation at 2- and 4-, but not 8-weeks of age in the Shunts. During normal development XO levels significantly increased over time in normal lambs but significantly decreased in the Shunts. In addition, XO protein levels were significantly increased in the Shunt at 2- and 4-weeks of age but significantly decreased at 8-weeks. Again this correlated with a significant increase in XO dependent superoxide generation at 2- and 4-, but not 8-weeks of age in the Shunts. Collectively, our findings suggest that NADPH oxidase and XO are major contributors to superoxide generation both during the normal development and during the development of pulmonary hypertension.
AB - Although alterations in ROS generating systems are well described in several vascular disorders, there is very limited information on the perinatal regulation of these systems in the lung both during normal development and in pulmonary hypertension. Thus, this study was undertaken to explore how the two predominant superoxide generating systems, nicotinamide adenine dinucleotide phosphate-oxidase (NADPH oxidase) and xanthine oxidase (XO), are developmentally regulated in control lambs and in our established lamb model of increased pulmonary blood flow (Shunt) over the first 2 months of life. We found that the levels of p47phox, p67phox, and Rac1 subunits of NADPH oxidase complex were altered. During the first two months of life there was no change in p47phox protein levels in either normal or Shunt lambs. However, both p67phox and Rac1 protein levels decreased over time. In addition, p47phox protein levels were significantly increased in shunt lambs at 2- and 4-, but not 8-weeks of age compared to age-matched controls while levels of the p67phox subunit were decreased at 8-weeks of age in the Shunts but unchanged at other time periods. Furthermore, Rac1 protein expression was significantly increased in the Shunts only at 4 weeks of age. These data correlated with a significant increase in NADPH oxidase dependent superoxide generation at 2- and 4-, but not 8-weeks of age in the Shunts. During normal development XO levels significantly increased over time in normal lambs but significantly decreased in the Shunts. In addition, XO protein levels were significantly increased in the Shunt at 2- and 4-weeks of age but significantly decreased at 8-weeks. Again this correlated with a significant increase in XO dependent superoxide generation at 2- and 4-, but not 8-weeks of age in the Shunts. Collectively, our findings suggest that NADPH oxidase and XO are major contributors to superoxide generation both during the normal development and during the development of pulmonary hypertension.
KW - Allopurinol
KW - Apocynin
KW - NADPH oxidase
KW - Pulmonary hypertension
KW - Xanthine oxidase
UR - http://www.scopus.com/inward/record.url?scp=77952428833&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77952428833&partnerID=8YFLogxK
U2 - 10.1016/j.vph.2010.03.005
DO - 10.1016/j.vph.2010.03.005
M3 - Article
C2 - 20362073
AN - SCOPUS:77952428833
SN - 1537-1891
VL - 53
SP - 38
EP - 52
JO - Vascular Pharmacology
JF - Vascular Pharmacology
IS - 1-2
ER -