Hmox1 Deficiency Sensitizes Mice to Peroxynitrite Formation and Diabetic Glomerular Microvascular Injuries

Abstract EN

Objective.

Indirect evidence suggests a role for heme oxygenase-1 (HO-1) in limiting diabetic vasculopathy.

The goal of this study was to assess the role of HO-1 in the development of microvascular lesions within glomeruli during diabetes mellitus using a mouse model with specific alteration of the Hmox1 gene.

Approach and Results.

The effects of Hmox1 haploinsufficiency were studied as a means of assessing the intrinsic contribution of HO-1 in the development of renal microvascular lesions during diabetes.

Renal function and histology were analyzed 10 weeks after diabetes induction with streptozotocin.

Diabetic Hmox1+/− mice showed higher levels of albuminuria and blood urea compared to their wild-type diabetic littermates.

More severe glomerular microvascular lesions were also observed in the diabetic Hmox1+/− mice.

This was associated with a renal increase in the expression of the oxidative stress marker, nitrotyrosine.

Conclusions.

Genetic Hmox1 partial deficiency is sufficient to sensitize mice to the development of diabetic glomerular microvascular lesions.

HO-1 exerts antioxidant effects in the kidney during diabetes mellitus.

These have protective effects on the development of glomerular endothelial injury.