BID and age-related macular degeneration: Humanin affects cells via both intracellular and extracellular mechanisms.13 Humanin can bind BAX protein, which prevents the coupling of tBid with BAX, and the release of cytochrome c, thereby inhibiting apoptosis.59 In untreated-AMD cybrids, the BAX protein levels were significantly elevated by 146% but declined drastically by 74% after HNG treatment.