Alzheimer’s disease and its related Dementia types: A review on their management via nanotechnology based therapeutic strategies

Background Dementia and its related types such as Alzheimer's disease, vascular dementia and mixed dementia belong to brain associated diseases, resulting in long-term progressive memory loss. These diseases are so severe that can affect a person's daily routine. Up to date, treatment of de- mentias is still an unmet challenge due to their complex pathophysiology and unavailable efficient pharmacological approaches. The use of nanotechnology based pharmaceutical products could possibly improve the management of dementia given that nanocarriers could more efficiently deliver drugs to the brain. Objective The objective of this study is to provide the current nanotechnology based drug delivery systems for the treatment of various dementia types. In addition, the current diagnosis biomarkers for the mentioned dementia types along with their available pharmacological treatment are being dis- cussed. Method An extensive review of the current nanosystems such as brain drug delivery systems against Alzheimer's disease, vascular dementia and mixed dementia was performed. Moreover, nan- otheranostics as possible imaging markers for such dementias were also reported. Results The field of nanotechnology is quite advantageous for targeting dementia given that nanoscale drug delivery systems easily penetrate the blood brain barrier and circulate in the body for prolonged time. These nanoformulations consist of polymeric nanoparticles, solid lipid nanoparticles, nanostruc- tured lipid carriers, microemulsions, nanoemulsions, and liquid crystals. The delivery of the nan- otherapeutics can be achieved via various administration routes such as transdermal, injectable, oral, and more importantly, through the intranasal route. Nonetheless, the nanocarriers are mostly limited to Alzheimer's disease targeting; thus, nanocarriers for other types of dementia should be developed. Conclusion To conclude, understanding the mechanism of neurodegeneration and reviewing the cur- rent drug delivery systems for Alzheimer's disease and other dementia types are significant for medical and pharmaceutical society to produce efficient therapeutic choices and novel strategies based on mul- tifunctional and biocompatible nanocarriers, which can deliver the drug sufficiently into the brain.