Background & objectives: Salvia officinalis is one of the memory-enhancing herbs that were used in the past. On the other hand, iron oxide nanoparticles which are widely used in medicine and industry may impair the brain process related to memory. In this investigation, the effect of hydro-alcoholic extract of Salvia officinalis on iron oxide nanoparticle induced memory impairment and the role of beta-adrenergic receptors in this effect were studied.
Methods: To assess the inhibitory avoidance memory, animals were trained in the step-down task and drugs (saline, hydro-alcoholic extract of sage leaves, nanoparticles of iron oxide and propranolol) were injected immediately after training by intraperitoneal (ip) injections. Long-term memory was tested 24 hours later and step-down latencies were recorded.
Results: Administration of iron oxide nanoparticles (5 mg/kg, ip) impaired memory retrieval. Salvia officinalis extract (40 mg/kg, ip) also prevented iron oxide nanoparticle induced long-term memory impairment. On the other hand, administration of propranolol (5, 10 mg/kg, ip) before Salvia officinalis extract (40 mg/kg, ip) and iron oxide nanoparticles (5 mg/kg, ip) attenuated the effect of Salvia officinalis extract.
Conclusion: It seems that extract of Salvia officinalis leaves decreases iron oxide nanoparticle induced memory impairment. Beta-adrenergic mechanisms are possibly involved in these effects of Salvia officinalis extract.