Insight into the role of adult hippocampal neurogenesis in aging and Alzheimer's disease

Alzheimer's disease (AD) is the most common form of dementia and seriously affects the quality of life of the elderly. Neurodegeneration is closely related to hippocampal dysfunction in AD patients. The hippocampus is key to creating new memories and is also one of the first areas of the brain to deteriorate with age. Mammalian neurogenesis occurs mainly in the hippocampus. Recent studies have confirmed that neurogenesis in the hippocampus is sustainable but decreases with age, which seriously affects the learning and memory function of AD patients. At present, our understanding of neurogenesis is still relatively shallow, especially pertaining to the influence and role of neurogenesis during aging and cognitive deficits in AD patients. Interestingly, many recent studies have described the characteristics of neurogenesis in animal models. This article reviews the progress of neurogenesis research in the context of aging and AD to provide new insights into neurogenesis. •Neurodegeneration is closely related to hippocampal dysfunction in AD patients.•Extent of neurogenesis is associated with cognitive status, and neurogenesis decline may be an early event in AD.•Glia-mediated neuroinflammation is a hallmark of AD and could have a huge impact on adult hippocampal neurogenesis in AD.•Increasing neurogenesis against disease progression was due to preventing neuronal cell death, thus providing a potentially powerful disease modification strategy for AD.•Single-cell sequencing, spatial metabolomics, and brain organoids can be used to study the molecular characteristics of neurogenic niches.