Effect and mechanism of verbascoside on hypoxic memory injury in plateau

Verbascoside is a water-soluble natural phenylethanoid glycoside and distributes widely in plants. It has been proved with antioxidant, neuroprotective, anti-inflammatory, antibacterial, and immunomodulatory bioactivities. In this experiment, the effect and mechanism of verbascoside on hypoxic memory injury were studied in a low-pressure and low-oxygen chamber. Verbascoside (50, 150, and 300 mg/kg) was intragastrically administered once a day for 7 days. On the fourth day, rats were placed in the chamber to simulate a 7,500 m high-altitude environment The eight-arm maze was used to test the memory ability. The levels of MDA, GSH, and T-SOD in plasma, brain-NH, and hippocampus were detected. The mRNA expression of mTOR, P70S6K, and 4E-BP1 in the hippocampus tissue was determined by PCR. The protein expression of P-mTOR, P-P70S6K, P-4E-BP1, and Cleaved Caspase-3 in the hippocampus tissue was determined by western blot. The results indicated that administration with verbascoside could obviously reduce the working memory error, reference memory error, total errors, and total time; relieve the neuron damage in CA₁ region of the hippocampus; and decrease the oxidative stress correlation enzyme activity in plasma, brain, and hippocampus. The amelioration of verbascoside on high altitude-induced memory impairment may be associated with the adjustment of oxidative stress and mTOR signaling pathway.