title: Nitrite anion therapy protects against chronic ischemic tissue injury in db/db diabetic mice in a NO/VEGF-dependent manner.
abstract: Nitrite anion has been demonstrated to be a prodrug of nitric oxide (NO) with positive effects on tissue ischemia/reperfusion injury, cytoprotection, and vasodilation. However, effects of nitrite anion therapy for ischemic tissue vascular remodeling during diabetes remain unknown. We examined whether sodium nitrite therapy altered ischemic revascularization in BKS-Lepr(db/db) mice subjected to permanent unilateral femoral artery ligation. Sodium nitrite therapy completely restored ischemic hind limb blood flow compared with nitrate or PBS therapy. Importantly, delayed nitrite therapy 5 days after ischemia restored ischemic limb blood flow in aged diabetic mice. Restoration of blood flow was associated with increases in ischemic tissue angiogenesis activity and cell proliferation. Moreover, nitrite but not nitrate therapy significantly prevented ischemia-mediated tissue necrosis in aged mice. Nitrite therapy significantly increased ischemic tissue vascular endothelial growth factor (VEGF) protein expression that was essential for nitrite-mediated reperfusion of ischemic hind limbs. Nitrite significantly increased ischemic tissue NO bioavailability along with concomitant reduction of superoxide formation. Lastly, nitrite treatment also significantly stimulated hypoxic endothelial cell proliferation and migration in the presence of high glucose in an NO/VEGF-dependent manner. These results demonstrate that nitrite therapy effectively stimulates ischemic tissue vascular remodeling in the setting of metabolic dysfunction that may be clinically useful.
authors.affiliation: Department of Pathology, Louisiana State University Health Sciences Center-Shreveport, Shreveport, LA.
authors.forename: Shyamal C
authors.initials: SC
authors.lastname: Bir
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Pattillo
authors.forename: Sibile
authors.initials: S
authors.lastname: Pardue
authors.forename: Gopi K
authors.initials: GK
authors.lastname: Kolluru
authors.forename: Xinggui
authors.initials: X
authors.lastname: Shen
authors.forename: Tony
authors.initials: T
authors.lastname: Giordano
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Kevil
mesh_terms: D000818:Animals; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000378:metabolism / Q000473:pathology; D005263:Femoral Artery / Q000187:drug effects / Q000378:metabolism; D006614:Hindlimb / Q000098:blood supply / Q000187:drug effects; D007511:Ischemia / Q000150:complications / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D051379:Mice; D009389:Neovascularization, Pathologic / Q000150:complications / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control; D009566:Nitrates / Q000494:pharmacology / Q000627:therapeutic use; D009569:Nitric Oxide / Q000378:metabolism*; D012977:Sodium Nitrite / Q000494:pharmacology / Q000627:therapeutic use*; D013997:Time Factors; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
chemical_list: D009566:Nitrates; D042461:Vascular Endothelial Growth Factor A; D009569:Nitric Oxide; C031618:sodium nitrate; D012977:Sodium Nitrite