Therapeutic approaches to delay the onset of Alzheimer's disease.

The key cytopathologies in the brains of Alzheimer's disease (AD) patients include mitochondrial dysfunction and energy hypometabolism, which are likely caused by the accumulation of small aggregates of amyloid-β (Aβ) peptides. Thus, targeting these two abnormalities of the AD brain may hold promising therapeutic value for delaying the onset of AD. In his paper, we discuss two potential approaches to delay the onset of AD. The first is the use of low dose of diaminophenothiazins (redox active agents) to prevent mitochondrial dysfunction and to attenuate energy hypometabolism. Diaminophenothiazines enhance mitochondrial metabolic activity and heme synthesis, both key factors in intermediary metabolism of the AD brain.The second is to use the naturally occurring osmolytes to prevent the formation of toxic forms of Aβ and prevent oxidative stress. Scientific evidence suggests that both approaches may change course of the basic mechanism of neurodegeneration in AD. Osmolytes are brain metabolites which accumulate in tissues at relatively high concentrations following stress conditions. Osmolytes enhance thermodynamic stability of proteins by stabilizing natively-folded protein conformation, thus preventing aggregation without perturbing other cellular processes. Osmolytes may inhibit the formation of Aβ oligomers in vivo, thus preventing the formation of soluble oligomers. The potential significance of combining diaminophenothiazins and osmolytes to treat AD is discussed.