Curcumin improves large elastic artery stiffness and reverses superoxide suppression of nitric oxide‐mediated vascular endothelial function in old mice

Abstract

We tested the hypothesis that curcumin, a polyphenol found in the Indian spice turmeric, improves age‐associated large elastic artery stiffness and vascular endothelial dysfunction. Old control C57 male mice (27 mo, n=8) had greater aortic pulse wave velocity (aPWV) vs. young control (6 mo n=7) (448 ± 15 vs. 349 ± 15 cm/s, p < 0.05) and 4 wk of curcumin supplemented chow (0.2%) reduced aPWV in old mice (396 ± 15 cm/s, n=8). Old control mice had impaired ex‐vivo carotid artery endothelium‐dependent dilation (EDD) to acetylcholine (ACh) vs. young (79 ± 3 vs. 93 ± 2%), mediated by a smaller nitric oxide (NO) component (EDD to ACh + LNAME minus EDD to ACh alone, 39 ± 11 vs 74 ± 6%) (both p < 0.05). Curcumin restored EDD in old mice (92 ± 1%) by restoring its NO component (61 ± 7%). Incubation with the superoxide dismutase mimetic, TEMPOL, selectively improved EDD in old control mice (91 ± 3%, p < 0.05), but had no effect in the other groups. Endothelium‐independent dilation did not differ between groups. Superoxide production (electron paramagnetic resonance spectroscopy) from aortic rings of old mice was greater vs. young control (7748 ± 897 vs. 4820 ± 492, p < 0.05), and was markedly reduced with curcumin supplementation (2486 ± 533, p < 0.05). Curcumin may be a novel therapeutic nutraceutical agent to destiffen large elastic arteries, restore NO‐mediated vascular endothelial function and reduce arterial superoxide production with aging.