| First Author | Xu M | Year | 2012 |
| Journal | Free Radic Biol Med | Volume | 52 |
| Issue | 2 | Pages | 357-65 |
| PubMed ID | 22100343 | Mgi Jnum | J:179385 |
| Mgi Id | MGI:5302145 | Doi | 10.1016/j.freeradbiomed.2011.10.485 |
| Citation | Xu M, et al. (2012) NAD(P)H oxidase-dependent intracellular and extracellular O2*- production in coronary arterial myocytes from CD38 knockout mice. Free Radic Biol Med 52(2):357-65 |
| abstractText | Activation of NAD(P)H oxidase has been reported to produce superoxide (O(2)(*-)) extracellularly as an autocrine/paracrine regulator or intracellularly as a signaling messenger in a variety of mammalian cells. However, it remains unknown how the activity of NAD(P)H oxidase is regulated in arterial myocytes. Recently, CD38-associated ADP-ribosylcyclase has been reported to use an NAD(P)H oxidase product, NAD(+) or NADP(+), to produce cyclic ADP-ribose (cADPR) or nicotinic acid adenine dinucleotide phosphate, which mediates intracellular Ca(2+) signaling. This study was designed to test a hypothesis that the CD38/cADPR pathway as a downstream event exerts feedback regulatory action on the NAD(P)H oxidase activity in production of extra- or intracellular O(2)(*-) in mouse coronary arterial myocytes (CAMs). By fluorescence microscopic imaging, we simultaneously monitored extra- and intracellular O(2)(*-) production in wild-type (CD38(+/+)) and CD38 knockout (CD38(-/-)) CAMs in response to oxotremorine (OXO), a muscarinic type 1 receptor agonist. It was found that CD38 deficiency prevented OXO-induced intracellular but not extracellular O(2)(*-) production in CAMs. Consistently, the OXO-induced intracellular O(2)(*-) production was markedly inhibited by CD38 shRNA or the CD38 inhibitor nicotinamide in CD38(+/+) CAMs. Further, Nox4 siRNA inhibited OXO-induced intracellular but not extracellular O(2)(*-) production, whereas Nox1 siRNA attenuated both intracellular and extracellular O(2)(*-) production in CD38(+/+) CAMs. Direct delivery of exogenous cADPR into CAMs markedly elevated intracellular Ca(2+) and O(2)(*-) production in CD38(-/-) CAMs. Functionally, CD38 deficiency or Nox1 siRNA and Nox4 siRNA prevented OXO-induced contraction in isolated perfused coronary arteries in CD38 WT mice. These results provide direct evidence that the CD38/cADPR pathway is an important controller of Nox4-mediated intracellular O(2)(*-) production and that CD38-dependent intracellular O(2)(*-) production is augmented in an autocrine manner by CD38-independent Nox1-derived extracellular O(2)(*-) production in CAMs. |
