Circulating humanin levels are associated with preserved coronary endothelial function.
Widmer. R J RJ; Flammer. A J AJ; Herrmann. J J; Rodriguez-Porcel. M M; Wan. J J; Cohen. P P; Lerman. L O LO; Lerman. A A
Key Findings
- Patients with coronary endothelial dysfunction had lower circulating humanin (1.3 ng/ml) than those with normal function (2.2 ng/ml).
- Humanin levels positively correlated with the increase in coronary blood flow after acetylcholine, a sign of better endothelial health.
- Traditional atherosclerosis markers (CRP, Lp‑Pla(2), homocysteine) did not correlate with humanin levels.
Practical Outcomes
- For biohackers, the study hints that boosting humanin could support vascular health, but no dosing or supplement form is established yet. Keep an eye on emerging humanin or analog products and consider monitoring vascular function if such interventions become available.
Summary
Higher levels of the tiny protein humanin in the blood are linked to better function of the heart's blood vessels, while lower levels are seen in people with poor vessel function. This suggests humanin might be a useful marker or even a treatment for heart health, but we don’t yet know how to safely raise its levels in humans.
Abstract
Humanin is a small endogenous antiapoptotic peptide, originally identified as protective against Alzheimer's disease, but subsequently also found on human endothelium as well as carotid artery plaques. Endothelial dysfunction is a precursor to the development of atherosclerotic plaques, which are characterized by a highly proinflammatory, reactive oxygen species, and apoptotic milieu. Previous animal studies demonstrated that humanin administration may improve endothelial function. Thus the aim of this study was to test the hypothesis that patients with coronary endothelial dysfunction have reduced systemic levels of humanin. Forty patients undergoing coronary angiography and endothelial function testing were included and subsequently divided into two groups based on coronary blood flow (CBF) response to intracoronary acetylcholine (normal ≥ 50% increase from baseline, n = 20 each). Aortic plasma samples were obtained at the time of catheterization for the analysis of humanin levels and traditional biomarkers of atherosclerosis including C-reactive protein, Lp-Pla(2), and homocysteine. Baseline characteristics were similar in both groups. Patients with coronary endothelial dysfunction (change in CBF = -33 ± 25%) had significantly lower humanin levels (1.3 ± 1.1 vs. 2.2 ± 1.5 ng/ml, P = 0.03) compared with those with normal coronary endothelial function (change in CBF = 194 ± 157%). There was a significant and positive correlation between improved CBF and humanin levels (P = 0.0091) not seen with changes in coronary flow reserve (P = 0.76). C-reactive protein, Lp-Pla(2), and homocysteine were not associated with humanin levels. Thus we observed that preserved human coronary endothelial function is uniquely associated with higher systemic humanin levels, introducing a potential diagnostic and/or therapeutic target for patients with coronary endothelial function.
Study Information
pubmed
2012
2012-12-07T00:00:00.000Z
10.1152/ajpheart.00765.2012
114
31