Rosmarinic acid (RA) is a natural
phenol that exerts different
biological activities, such as
antioxidant activity and
neuroprotective effects. In this study, we hypothesized that administration of RA (8, 16, and 32 mg/kg, p.o.) for 7 days would effect on
scopolamine-induced
cognitive dysfunction as an extensively used model of
cognitive impairment. The rats were divided into 10 groups. The acquisition trial was done 1h after the last administration of RA. Animals were divided into control, RA (8, 16, and 32 mg/kg) and
donepezil (2 mg/kg) treated controls,
scopolamine, RA (8, 16, and 32 mg/kg), and
donepezil (2 mg/kg) treated
scopolamine groups. Memory impairment was induced by
scopolamine treatment (1 mg/kg, i.
p.) 30 min after the administration of RA,
donepezil, or saline.
Scopolamine administration caused cognition deficits in the PAL and memory paradigm. While orally RA administration (16 and 32 mg/kg) improved learning and memory in control rats, it reversed learning and
memory deficits of
scopolamine received groups. Administration of RA at the dose of 8 mg/kg did not alter cognitive function in control and
scopolamine treated groups. The combination of
anticholinesterase, neuroprotective, and
antioxidant properties of RA may all be responsible for the observed effects. These results indicate the beneficial effects of subchronic RA administration in passive avoidance learning and memory in control rats as well as in a pharmacological model of
cholinergic deficit which continue to expand the knowledge base in creating new treatment strategies for cognition deficits and
dementia. Of course, further studies are warranted for clinical use of RA in the management of demented subjects.