Alzheimer's disease (AD) is the most common fatal neurodegenerative disease (ND),) characterized by loss of neuronal structure and function. Over the past few decades, AD and its associated risk factors have become a major health care problem in most developed countries. In addition, Alzheimer's disease is reported to be the fifth leading cause of death among people over 65 years of age, with an incidence of more than 5 million cases per year in the United States (Alzheimer's Association, 2017). The World Health Organization (WHO) estimates that the prevalence of Alzheimer’s disease worldwide will quadruple to about 114 million people by 2050 (Alzheimer's Association, 2017).
The pathological features of AD include extracellular plaques (extracellular amyloid plaques) and neurofibrillary tangles within neurons (hyperphosphorylated tau protein accumulation; Vanitallie, 2015). These pathological changes gradually lead to loss of neurons, and ultimately lead to neuron death. Although the etiology and pathogenesis of AD is still unclear, the amyloid cascade theory has been widely accepted and supported by some studies (Drachman, 2014; Herrup, 2015). A protective mutation of amyloid precursor protein (APP) (APP) was found near the β -cleavage site of amyloid precursor protein (APP), which could prevent the development of late-onset dementia (Jonsson et al., 2012). This assumption is further reinforced.
In the past few years, the applicability of several Aβ aggregation peptide inhibitors as new therapeutic lead compounds has been studied. In conclusion, very few IA β5, Aβ 12-28P, LPYF Da, Trp-Aib, D-4F and D3 are effective in rodent models. It is not clear whether peptide inhibitors should target Aβ, oligomeric Aβ or Aβ fibrils deposited in plaques. It is not clear whether Aβ 1-40 or Aβ 1-42 should be treated, and weather compounds need to pass through BBB to be effective. More work needs to be done to elucidate the properties of the most synaptotoxic Aβ species in the genesis and development of AD. The ongoing studies on the peptides of different Aβ species and their effects on the aggregation and toxicity of Aβ will provide a basis for further understanding the molecular mechanism of AD.
References
