Brazilin-rich extract from Sappan wood attenuates neuroinflammation through the restoration of the gut microbiota: improving cognitive function in mice with age-related Alzheimer’s disease

Alzheimer’s disease is an age-related neurodegenerative disorder characterized by amyloid-β accumulation, which leads to memory impairment, neuroinflammation, and imbalance in the gut microbiota. Targeting neuroinflammation and correcting the imbalance in the gut microbiota may be promising strategies for treating age-related Alzheimer’s disease. Sappan wood, a traditional Chinese medicine known for its neuroprotective and anti-inflammatory properties, has not been extensively studied for its effects on cognitive function in age-related Alzheimer’s disease and neuroinflammation. In this study, we demonstrated that Sappan wood extract, brazilin, is nontoxic and reduces the degree of cytotoxicity induced by amyloid-β oligomers in PC12 cells. Sappan wood extract can alleviate cognitive deficits and protect hippocampal neurons in the mouse model of age-related Alzheimer’s disease by reducing neuroinflammation caused by amyloid-β42 oligomers. Furthermore, Sappan wood extract significantly reverses the imbalance in the gut microbiota caused by amyloid-β oligomers, enhancing resistance to inflammatory damage and age-related Alzheimer’s disease. Therefore, Sappan wood extract shows significant potential for combating age-related Alzheimer’s disease by improving cognitive impairment and inhibiting neuroinflammation through the modulation of the gut microbiota.