Tetrandrine ameliorates sevoflurane‑induced cognitive impairment via the suppression of inflammation and apoptosis in aged rats.

Tetrandrine is a bisbenzylisoquinoline alkaloid extracted from Stephania tetrandra, a traditional Chinese herbal medicine, which has been observed to exert anti‑inflammatory effects. The aim of the current study was to investigate whether tetrandrine was able to ameliorate sevoflurane‑induced cognitive impairment in aged rats. Male 20‑month‑old Sprague‑Dawley rats underwent sevoflurane‑induction in an environment containing 2% sevoflurane for 5 h. The Morris water maze test was used to measure the effect of tetrandrine on learning and memory in sevoflurane‑treated aged rats. Western blot analysis of the protein expression levels of cyclooxygenase‑2 (COX‑2), inducible nitric oxide synthase (iNOS) and Bcl‑2 was conducted. ELISAs were used to measure the levels of interleukin (IL)‑1β, tumor necrosis factor (TNF‑α), nuclear factor‑κB (NF‑κB) and caspase‑3. In the present study, tetrandrine improved the learning and memory deficits observed in sevoflurane‑treated aged rats. Treatment with tetrandrine reduced the expression levels of COX‑2, IL‑1β, TNF‑α, NF‑κB, iNOS and caspase‑3, and increased the Bcl‑2 protein expression in sevoflurane‑treated aged rats. In conclusion, the current study indicated that tetrandrine ameliorates sevoflurane‑induced cognitive impairment via the suppression of inflammation and apoptosis in aged rats. Thus, tetrandrine may be a potential novel candidate to protect against the effects of sevoflurane anesthesia on cognitive function.