Fig. 1

HYP upregulates the NO production and the expression of nNOS, BDNF, and phosphorylated TrkB in primary hippocampal neurons. (A) Chemical structure of HYP. (B) NO production in neuronal cells was assessed by treating cells with 10 nM (E2) and 0.1 or 1 µM HYP for 24 h. NO levels were measured using the indicator DAF-FM, and fluorescence quantification was done with a microplate reader (excitation: 495 nm, emission: 515 nm). Visualization and cell count of positive NO signals were performed using fluorescence microscopy. (C) Cultured hippocampal neuronal cells were treated with 10 nM E2 and 0.1 or 1 µM HYP for 24 h. Western blot showing the protein expression of nNOS, BDNF and phosphorylated TrkB. Results are presented as mean ± SE. *P < 0.05, **P < 0.01, *** P < 0.001 vs. CTL (vehicle-only treated cell). BDNF, brain-derived neurotrophic factor; E2, 17β-estradiol; HYP, hyperoside; nNOS, neuronal nitric oxide synthase; NO, nitric oxide; TrkB, tropomyosin receptor kinase B