The effects of pre-treatment with olibanum and its constituent, boswellic acid on synaptic plasticity impairments induced by lipopolysaccharide in rats

Document Type: Original Research Article

Authors

1 Neurogenic Inflammation Research Center and Department of Physiology, School of Medicine, Mashhad University of Medical Sciences, Iran.

2 Neuroscience Research Center, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran

3 Mollecular Medicine Department, Mashhad University of Medical Sciences, Mashhad, Iran

4 Student Research Committee, Department of Physiology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

5 Division of Neurocognitive Sciences, Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

10.22038/ajp.2020.16145

Abstract

Objective: Olibanum (OLIB) and its component boswellic acid (BOSA) are suggested to have anti-inflammatory, anti-oxidant and neuroprotective effects. In the present work, we examined effect of OLIB, and BOSA on the synaptic plasticity impairment and oxidative stress indicators in a rat model of neuro-inflammation induced by lipopolysaccharide (LPS).
Materials and Methods: Forty rats were divided into the following four groups: (1) Control, (2) LPS, (3) OLIB (200 mg/kg), and (4) BOSA (10 mg/kg). The animals were pre-treated with OLIB extract, BOSA or the vehicle 30 min before LPS (1 mg/kg) administration, for 6 days. On the 6th day, electrophysiological recording was done. Long-term potentiation (LTP) from CA1 area of hippocampus was assessed. The animals were then sacrificed and their brains were removed for evaluation of the levels of interleukin-6 (IL-6), nitric oxide (NO) metabolites, malondialdehyde (MDA), thiol, superoxide dismutase (SOD) and catalase (CAT) in the cortex.
Results: Administration of LPS decreased amplitude (p<0.001) and slope (p<0.01) of field excitatory postsynaptic potential (fEPSP). Pre-treatment enhanced these parameters (p<0.05 to p<0.001). LPS also increased cortical levels of IL-6 (P<0.01), NO, and MDA (p<0.001) while decreased thiol, SOD (p<0.001), and CAT (p<0.05). OLIB and BOSA diminished IL-6 (p<0.05-p<0.001), NO (p<0.01-p<0.001) and MDA level (p<0.01 and p<0.001, respectively) while improved SOD (p<0.05 and p<0.001, respectively), CAT (p<0.05 and p<0.001, respectively) and thiol content (p<0.001).
Conclusion: The results showed that OLIB and BOSA could improve synaptic plasticity impairment induced by LPS as shown by a decrease in an inflammation indicator along with the anti-oxidant effects. 

Keywords