Abstract
Recent findings have improved our understanding of the multifactorial nature of AD. While in early asymptomatic stages of AD, increased amyloid-β synthesis and tau hyperphosphorylation play a key role, while in the latter stages of the disease, numerous dysfunctions of homeostatic mechanisms in neurons, glial cells, and cerebrovascular endothelium determine the rate of progression of clinical symptoms. The main driving forces of advanced neurodegeneration include increased inflammatory reactions in neurons and glial cells, oxidative stress, deficiencies in neurotrophic growth and regenerative capacity of neurons, brain insulin resistance with disturbed metabolism in neurons, or reduction of the activity of the Wnt-β catenin pathway, which should integrate the homeostatic mechanisms of brain tissue. In order to more effectively inhibit the progress of neurodegeneration, combination therapies consisting of drugs that rectify several above-mentioned dysfunctions should be used. It should be noted that many widely-used drugs from various pharmacological groups, "in addition" to the main therapeutic indications, have a beneficial effect on neurodegeneration and may be introduced into clinical practice in combination therapy of AD. There is hope that complex treatment will effectively inhibit the progression of AD and turn it into a slowly progressing chronic disease. Moreover, as the mechanisms of bidirectional communication between the brain and microbiota are better understood, it is expected that these pathways will be harnessed to provide novel methods to enhance health and treat AD.
Keywords: Alzheimer’s disease, inflammation, oxidative stress, Wnt-β catenin pathway, combination therapy, brain insulin resistance.
Graphical Abstract
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