Solution structure of Ser14Gly-humanin, a potent rescue factor against neuronal cell death in Alzheimer's disease.
Benaki. Dimitra D; Zikos. Christos C; Evangelou. Alexandra A; Livaniou. Evangelia E; Vlassi. Metaxia M; Mikros. Emmanuel E; Pelecanou. Maria M
Key Findings
- S14G‑humanin is ~1,000‑fold more potent than regular humanin in neuroprotection
- In aqueous solution the peptide is flexible with turn‑like structures from residues Pro3 to Glu15
- In 30% TFE (more lipophilic) it adopts an α‑helical segment spanning Phe6‑Thr13
- Flexibility appears important for its neuroprotective activity
Practical Outcomes
- The key takeaway for DIY health enthusiasts is that the S14G version of humanin is dramatically more potent, and its effectiveness may depend on how it folds, which can be influenced by the surrounding environment. Formulations that provide a slightly lipophilic milieu might boost its activity, but the study does not give dosage or direct usage instructions.
Summary
Scientists mapped the shape of a modified humanin peptide (S14G‑humanin) that is about 1,000 times stronger at protecting brain cells from Alzheimer‑related damage. In water the peptide is flexible, while in a more oily setting it forms a helix, and this flexibility may help it interact with its targets.
Abstract
The NMR solution study of Ser14Gly-humanin (S14G-HN), a 1000-fold more potent derivative of humanin (HN), is reported. HN is 24-residue peptide that selectively suppresses neuronal cell death caused by Alzheimer's disease (AD)-specific insults and offers hope for the development of a cure against AD. In aqueous solution the NMR data show that S14G-HN is a flexible peptide with turn-like structures in its conformational ensemble distributed over an extensive part of its sequence from Pro3 to Glu15. In the more lipophilic environment of 30% TFE, an alpha-helical structure spanning residues Phe6 to Thr13 is identified. Comparison of these findings to the NMR structure of the parent HN and to existing structure-function relationship literature data outlines the important for activity structural features for this class of neuroprotective peptides, and brings forth flexibility as an important characteristic that may facilitate interactions with functional counterparts of the neuroprotection pathway.
Study Information
pubmed
2006
2006-08-23T00:00:00.000Z
10.1016/j.bbrc.2006.08.087