Frankincense improves memory retrieval in rats treated with Lipopolysaccharide

Abstract

Introduction: Frankincense has been shown to possess anti-inf lammatory activity. In this studythe effect of pretreatment with the hydro-alcoholic extract of frankincense on memory retrievalwas assessed in lipopolysaccharide (LPS) treated rats.Methods: Forty-two adult male Wistar rats were distributed into 7 groups of 6 each. One groupreceived LPS (1 mg/kg; i.p) pre-test. The control group received saline (1 ml/kg; i.p). 2 groups ofanimals received frankincense (50 mg/kg; P.O) or DMSO 5% (1 ml/kg; P.O) and 30 minutes laterLPS (1 mg/kg; i.p). Two other groups of animals received frankincense (50 mg/kg; P.O) or DMSO5% (1 ml/kg; P.O) and 30 minutes later saline (1 ml/kg; i.p). Another group of rats received LPS(1 mg/kg; i.p) and 30 minutes later Ibuprofen (100 mg/kg; P.O). In all the experimental groups,memory retrieval was assessed 4 hours following the last injection, using a passive avoidancetask (PAT). Hippocampal TNF-α levels were measured by ELISA as an index of LPS-inducedneuroinf lammation.Results: LPS impaired memory retrieval by decreasing step-through latency (STL), significantly.LPS also increased levels of TNF-α in the hippocampus as compared to the control group.Administration of frankincense (50 mg/kg; P.O) before LPS (1 mg/kg; i.p) improved memoryretrieval as compared to the control group. Frankincense reduced hippocampal TNF-α level in theLPS treated rats, significantly, compared to the control group.Conclusion: The results indicate that the hydro-alcoholic extract of frankincense has the potentialto improve memory retrieval in LPS treated rats, possibly via an anti-neuroinf lammatory activity.

Keywords: Lipopolysaccharide, Memory, Frankincense, Neuroinflammation