Advances in Alzheimer’s disease therapeutics: biochemistry, exploring bioactive compounds and novel approaches

Figures & data

Figure 1. Kinases and phosphatases control how the tau protein stabilizes microtubules. The production of intractable cytoplasmic tau oligomers and protomers, which assemble to create protomers, are the results of abnormal hyperphosphorylation of tau proteins, which has disastrous effects on microtubule depolymerization. PHFs, which are made up of two protomers coiled around one another, come together to form neurofibrillary tangles (NFTs)^[50].

Figure 2. The processing of APP by beta-site AβPPcleaving enzyme (BACE1) and the mechanisms of actions of phytochemicals in AD.

Table 1. A Summary of the Information on the Pharmacological Effects of Plant Chemicals as possible agents for the Treatment of AD.

Plant Chemicals	Origin	Effects	Experimental Model	References
Catechin	Tea Plant (Camellia sinensis)	Antioxidant Anti-cholinesterase Anti-amyloidogenic	Acetylcholinesterase mouse modelIn vitro PC12 cells In vitro PC12 cells	^[Citation249–251]
Galantamine	Caucasian snowdrop (Galanthus alpinus)	Anti-inflammatory Antioxidant Anti-cholinesterase Anti-amyloidogenic	In vitro APPswe/PS1dE9 mouse model Neuroblastoma SH-5ySy cells	^[Citation252–254]
Berberine	Tree Turmeric (Berberis aristata); Barberry (Berberis vulgaris)	Tau Anti-hyperphosphorylation Antioxidant Anti-amyloidogenic Anti-neuroinflammatory	In vivo transgenic mice model	^[Citation255,Citation256]
Curcumin	Turmeric (Curcuma longa)	Anti-amyloidogenic Antioxidant	AD-model of Caenorhabditis elegans	^[Citation257,Citation258]
Trans-Resveratrol	Grape (Vitis vinifera)	Anti-neuroinflammatory Antioxidant Tau Anti-hyperphosphorylation Anti-amyloidogenic	Mouse model SH-5ySy cells Microglia Munira BV-2	^[Citation259,Citation260]
Anthocyanin	Blueberry (Vaccinium corymbosum), Common Bean (Phaseolus vulgaris)	Anti-amyloidogenic Antioxidant	Mouse model neuroblastoma cells APP/PS1 mouse model	^[Citation261,Citation262]

Table 2. A summary of the Information on the Vaccines that might be used to treat AD.

Candidate Vaccine’s Target in AD	Name of Vaccine and Producer	Effects	References
Tau Vaccines	ACI-35.030 (AC Immune)	1. No beneficial effect on tau 2. Bolster the immunological system	^[Citation117]
	AADvac1 (Axon Neuroscience)	Enhance mental capacity	^[Citation118]
Amyloid-beta Vaccines	UB-311 (Vaxxinity)	Enhance mental capacity	^[Citation119]
	ABvac 40 (Araclon Biotech’s)	Enhance mental capacity	^[Citation120]
	ACI-24 (AC Immune)	Accelerated removal of β-amyloid plaques	^[Citation121]
Immunomodulatory Vaccines	GV1001 GemVax (KAEL Bio)	Facilitated the removal of tau tangles and β-amyloid plaques – anti-neuroinflammatory	^[Citation122]
	Bacillus Calmette-Guerin (Mindful Diagnostics and Therapeutics)	Immunostimulatory effect on β-amyloid plaques via nasal administration	^[Citation123]
	Protollin (Brigham and Women’s Hospital)	Bolster immunological defense	^[Citation124]

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Data availability statement

Data available on request from the authors.