| First Author | Toporsian M | Year | 2005 |
| Journal | Circ Res | Volume | 96 |
| Issue | 6 | Pages | 684-92 |
| PubMed ID | 15718503 | Mgi Jnum | J:107645 |
| Mgi Id | MGI:3621594 | Doi | 10.1161/01.RES.0000159936.38601.22 |
| Citation | Toporsian M, et al. (2005) A role for endoglin in coupling eNOS activity and regulating vascular tone revealed in hereditary hemorrhagic telangiectasia. Circ Res 96(6):684-92 |
| abstractText | Decreased endothelial NO synthase (eNOS)-derived NO bioavailability and impaired vasomotor control are crucial factors in cardiovascular disease pathogenesis. Hereditary hemorrhagic telangiectasia type 1 (HHT1) is a vascular disorder associated with ENDOGLIN (ENG) haploinsufficiency and characterized by venous dilatations, focal loss of capillaries, and arteriovenous malformations (AVMs). We report that resistance arteries from Eng+/- mice display an eNOS-dependent enhancement in endothelium-dependent dilatation and impairment in the myogenic response, despite reduced eNOS levels. We have found that eNOS is significantly reduced in endoglin-deficient endothelial cells because of decreased eNOS protein half-life. We demonstrate that endoglin can reside in caveolae and associate with eNOS, suggesting a stabilizing function of endoglin for eNOS. After Ca2+-induced activation, endoglin-deficient endothelial cells have reduced eNOS/Hsp90 association, produce less NO, and generate more eNOS-derived superoxide (O2-), indicating that endoglin also facilitates eNOS/Hsp90 interactions and is an important regulator in the coupling of eNOS activity. Treatment with an O2- scavenger reverses the vasomotor abnormalities in Eng(+/-) arteries, suggesting that uncoupled eNOS and resulting impaired myogenic response represent early events in HHT1 pathogenesis and that the use of antioxidants may provide a novel therapeutic modality. |
