RESUMO
Alzheimer's disease（AD） is an irreversible neurodegenerative disease with clinical manifestations such as memory impairment， aphasia， impaired visuospatial skills， executive function impairment， and personality changes. AD has brought a heavy burden to the family and society due to its unrevealed pathogenesis and the lack of therapeutic approaches. Saponins， a group of oligoglycosides whose aglycones are triterpenes or spirosteroids， are divided into triterpene saponins and steroidal saponins， which have a variety of biological activities. At present， there is no systematic review on the anti-AD effect of saponins. According to the literature published in recent years， the authors summarized the studies of saponins in improving AD based on animal experiments. The results indicated that saponins enhanced learning ability and improved cognitive impairment by inhibiting amyloid β-protein （Aβ） cascade activity， suppressing microtubule-associated protein （tau） hyperphosphorylation， inhibiting neuronal oxidative stress， inhibiting inflammatory factors， regulating apoptosis， inhibiting cholinergic neuronal degeneration， promoting mitochondrial autophagy， regulating intestinal flora， and enhancing energy metabolism， which in turn improved the pathological state of AD animal models. The therapeutic effects of different saponins on AD are different. The present study discussed the effect of different aglycones and sugar chains on the anti-AD activity based on saponins and anti-AD effect to provide new ideas and a theoretical basis for the development and utilization of saponins.
RESUMO
Alzheimer′s disease (AD) is an incurable disease in the field of major chronic diseases. Subjective cognitive decline (SCD) is a clinical risk factor for AD. The standardized screening and intervention in individuals with SCD are of great importance in early prevention and treatment of AD. According to the clinical criteria proposed by The characterisation of subjective cognitive decline, which was published online in Lancet Neurology, the article summarized the definition of SCD, the latest perspective of clinical standards in SCD, and the results of AD preclinical SCD research. The purpose of this work was to provide concrete guidance and recommendations for making clinical decisions in diagnosis and scientific research on SCD.