Diarylheptanoids with neuroprotective effects from Alpinia officinarum rhizomes

Forty-three diarylheptanoids were isolated from Alpinia officinarum rhizomes among them eight ones (1-6) were undescribed compounds whose structures were identified by UV, IR, HRESIMS, and NMR. The neuroprotective effects of these diarylheptanoids were evaluated on H₂O₂-damaged SH-SY5Y cells. Compounds 7, 10, 12, 20, 22, 25, 28, 33, 35, 37, and 42 presented significant neuroprotective effects than that of the positive control (EGCG) at the concentrations of 5, 10 or 20 μM. Compounds 10, 22, 25, and 33 significantly reduced the ROS levels and inhibited the generations of MDA and NO in oxidative injured cells to display neuroprotective effects. This study lay the foundation for the application of Alpinia officinarum rhizomes.