Effects of aging and high fat diet on endothelial function in middle cerebral arteries is not additive (1070.11)

Abstract

Vascular dysfunction in cerebral arteries has been associated with cognitive impairments with advancing age and disease. It is not known, however, how aging and consumption of a high fat (HF) obesigenic diet interact to impact cerebrovascular function. We examined endothelium dependent dilation (EDD) to acetylcholine in the middle cerebral arteries of young (6‐8 mo) and old (29‐31 mo) normal chow (NC) and HF diet fed mice. Maximal EDD was reduced with aging (68 ± 6 vs. 40 ± 2%, P<0.01) in NC mice. HF reduced EDD in young (41 ± 3%, P<0.01) but was without effect in old (34 ± 5%, P=0.3) mice. Differences in maximal EDD with aging and after HF diet were eliminated after inhibition of nitric oxide (NO) synthase by L‐NAME, indicating that the impairments resulted from reduced NO bioavailability. There were no differences in endothelium independent dilation to sodium nitroprusside between groups (P’s>0.5). Advancing age and consumption of a HF diet independently reduce cerebrovascular endothelial function through reductions in NO, but there is no further decrement in old mice fed HF diet.Grant Funding Source: Supported by NIH grants: R21 AG033755, K01 AG033196, R01 AG040297