A Review of the Pathogenesis and Chinese Medicine Intervention of Alzheimer's Disease

Abstract

Alzheimer's disease (AD) is an age-related neurodegenerative disease that is primary characterized as a cognitive disorder. Its pathology is characterized by the formation of senile plaques in the brain from amyloid-beta (Aβ) aggregation, neuronal fibrillary tangles from hyperphosphorylated tau protein aggregation, prolonged inflammatory responses, and neuronal death. The pathogenesis and clinical manifestations of AD are complex, but aging is generally accepted as one of the most important contributing factors. In addition, there are several hypotheses, including the Aβ hypothesis based on amyloid plaques, the tau hypothesis based on neuronal fiber entanglement, the inflammation hypothesis based on long-term inflammatory responses causing brain damage, and the neuroprotection hypothesis based on synaptic dysfunction and neuronal death. Although the pathogenesis of AD has been broadly classified into four major hypotheses, there are multiple forms of interactions, which is one of the reasons for its complex pathogenesis. Numerous epidemiological studies have shown the important role of genes in AD, followed by brain damage, hyperlipidemia, diabetes, hypertension, and obesity as risk factors for the disease. Despite years of research, several mysteries in AD remain unsolved. Drugs based on various pathogenetic hypotheses are being investigated in large numbers, but the effects are unsatisfactory. In recent years, traditional Chinese medicine (TCM) has made excellent progress and is expected to provide a new possibility for AD treatment. In this review, we focus on the latest developments in studies on the risk factors-Aβ aggregates and related factors such as apolipoprotein E, synaptic loss, and fatty acids, and then present the progress in the research of TCM based on the above pathogenesis, intended to provide a research reference and treatment for AD.

The glymphatic system: a new perspective on brain diseases

“…Metabolites in the central nervous system, such as Aβ, α-Synuclein, tau protein, and lactic acid, can also be discharged from the brain through the glymphatic system ( Rasmussen et al, 2022 ). Aβ exists in the brain interstitium, and its abnormal precipitation is closely related to neurodegenerative diseases such as Alzheimer’s ( Zhao J. et al, 2022 ). From investigations, the fluorescence-labeled Aβ is transported along the glymphatic system pathway in the central nervous system.…”

Total flavonoids of Cynomorium songaricum attenuates cognitive defects in an Aβ1-42-induced Alzheimer’s disease rat model by activating BDNF/TrkB signaling transduction

“…Traditional Chinese Medicine (TCM) is a treasury for discovering natural compounds with multiple promising pharmacological effects. Certain natural compounds from TCM have been shown to ameliorate cognitive impairment by improving mitochondrial dysfunction and repairing neuroplasticity in patients with neurodegenerative disorders via multiple mechanisms [3][4][5]. Regarding the treatment of AD, there are some Chinese medicine extracts also showing considerable effects.…”

Meta-analysis of the Efficacy of Traditional Chinese Medicine in the Treatment of Alzheimer's Disease

“…They are agonists or antagonists of neurotransmitter production or neurotransmitter receptors. These drugs have varying degrees of side effects in clinical use and are single-target drugs [6] . Such as acetylcholinase inhibitors (Donepezil, cabaladine, etc.…”