Humanin: a novel central regulator of peripheral insulin action.
Muzumdar. Radhika H RH; Huffman. Derek M DM; Atzmon. Gil G; Buettner. Christoph C; Cobb. Laura J LJ; Fishman. Sigal S; Budagov. Temuri T; Cui. Lingguang L; Einstein. Francine H FH; Poduval. Aruna A; Hwang. David D; Barzilai. Nir N; Cohen. Pinchas P
Key Findings
- Central (brain) infusion of Humanin improves whole‑body insulin sensitivity via hypothalamic STAT‑3 activation
- Peripheral infusion of potent Humanin analogues mimics the brain effect, but the liver benefit still depends on brain STAT‑3 signaling
- A single dose of a high‑potency Humanin analogue reduces blood glucose in Zucker diabetic fatty rats
- Humanin levels decline with age in mouse and human tissues and blood, correlating with higher risk of diabetes and neurodegeneration
Practical Outcomes
- For biohackers, the data suggest that boosting Humanin—especially using stable, high‑potency analogues—could be a strategy to enhance insulin sensitivity and lower blood sugar. While direct brain infusion isn’t practical, peripheral administration (e.g., subcutaneous or IV peptide) might work if a suitable analogue is available. However, human trials are still lacking, so any self‑experiment should start with low doses, monitor glucose and insulin markers closely, and consider the regulatory and safety uncertainties.
Summary
Humanin is a naturally‑occurring peptide that drops with age and seems to boost insulin sensitivity when given directly to the brain or as a powerful analogue in the bloodstream. In animal studies, it activates a brain pathway (STAT‑3) that improves how the liver handles sugar, and a single dose of a strong analogue lowered blood glucose in diabetic rats. Human levels also fall with age, linking the peptide to both diabetes and Alzheimer’s risk.
Abstract
Decline in insulin action is a metabolic feature of aging and is involved in the development of age-related diseases including Type 2 Diabetes Mellitus (T2DM) and Alzheimer's disease (AD). A novel mitochondria-associated peptide, Humanin (HN), has a neuroprotective role against AD-related neurotoxicity. Considering the association between insulin resistance and AD, we investigated if HN influences insulin sensitivity. Using state of the art clamp technology, we examined the role of central and peripheral HN on insulin action. Continuous infusion of HN intra-cerebro-ventricularly significantly improved overall insulin sensitivity. The central effects of HN on insulin action were associated with activation of hypothalamic STAT-3 signaling; effects that were negated by co-inhibition of hypothalamic STAT-3. Peripheral intravenous infusions of novel and potent HN derivatives reproduced the insulin-sensitizing effects of central HN. Inhibition of hypothalamic STAT-3 completely negated the effects of IV HN analog on liver, suggesting that the hepatic actions of HN are centrally mediated. This is consistent with the lack of a direct effect of HN on primary hepatocytes. Furthermore, single treatment with a highly-potent HN analog significantly lowered blood glucose in Zucker diabetic fatty rats. Based upon the link of HN with two age-related diseases, we examined if there were age associated changes in HN levels. Indeed, the amount of detectable HN in hypothalamus, skeletal muscle, and cortex was decreased with age in rodents, and circulating levels of HN were decreased with age in humans and mice. We conclude that the decline in HN with age could play a role in the pathogenesis of age-related diseases including AD and T2DM. HN represents a novel link between T2DM and neurodegeneration and along with its analogues offers a potential therapeutic tool to improve insulin action and treat T2DM.
Study Information
pubmed
2009
2009-07-22T00:00:00.000Z
10.1371/journal.pone.0006334
223
44