Alzheimer's disease (AD) is a major neurodegenerative disease in the aging global population. Exploring the underlying mechanism is helpful to develop the novel strategy. Lipid metabolism disorder is the core accelerator of the occurrence and development of AD. Lipid deposition exacerbates the aging of microglia and astrocytes, leading to neural dysfunction, and consequently, neurodegeneration. In recent years, the crosstalk of gut microbiota and lipid metabolism has gained increasing attention. The gut microbiota and its metabolic products interfere with brain lipid metabolism via the gut-brain axis. This review explores the detrimental interactions between the disorder of lipid metabolism and gut microbiota, discusses its implications in potential pathogenesis, and highlights how restoring the imbalance ameliorates AD progression.
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