Effect of Salvia miltiorrhiza root extract on brain acetylcholinesterase and butyrylcholinesterase activities, their mRNA levels and memory evaluation in rats.

Salvia miltiorrhiza (Lamiaceae), one of the most important and popular plants of traditional medicine of Asia, is used for the prevention and treatment of cardiovascular diseases and in central nervous system disturbances. The main aim of this study was to assess the influence of subchronic (28-fold) administration of Salvia miltiorrhiza root extract (SE, 200mg/kg, p.o.) on behavioural activity and memory of rats and to evaluate the activities of cholinesterases (AChE and BuChE) and gene expression levels of AChE and BuChE as well as of beta-secretase (BACE1) in the hippocampus and frontal cortex in vivo. Huperzine A (HU, 0.5mg/kg b.w., p.o.) served as a positive control substance, whereas scopolamine (0.5mg/kg, i.p.) injection was used as a well-known model of memory impairment. The results showed that subchronic administration of SE led to an improvement of long-term memory of rats. Strong inhibition of AChE and BuChE mRNA transcription in the frontal cortex of rats treated with SE or HU was observed. The BACE1 transcript level was significantly decreased. AChE activity was statistically significantly inhibited in the frontal cortex and the hippocampus by SE (47% and 55%, respectively). Similar effects were observed in the case of HU. In summary, activity of SE provides evidence that the plant can be a source of drugs used in the treatment of Alzheimer disease.