Xanthone-enriched fraction of Garcinia mangostana and α-mangostin improve the spatial learning and memory of chronic cerebral hypoperfusion rats.

OBJECTIVES: Xanthones isolated from the pericarp of Garcinia mangostana has been reported to exhibit neuroprotective effect. METHODS: In this study, the effect of xanthone-enriched fraction of Garcinia mangostana (XEFGM) and α-mangostin (α-MG) were investigated on cognitive functions of the chronic cerebral hypoperfusion (CCH) rats. KEY FINDINGS: HPLC analysis revealed that XEFGM contained 55.84% of α-MG. Acute oral administration of XEFGM (25, 50 and 100 mg/kg) and α-MG (25 and 50 mg/kg) before locomotor activity and Morris water maze (MWM) tests showed no significant difference between the groups for locomotor activity. CONCLUSIONS: However, α-MG (50 mg/kg) and XEFGM (100 mg/kg) reversed the cognitive impairment induced by CCH in MWM test. α-MG (50 mg/kg) was further tested upon sub-acute 14-day treatment in CCH rats. Cognitive improvement was shown in MWM test but not in long-term potentiation (LTP). BDNF but not CaMKII was found to be down-regulated in CCH rats; however, both parameters were not affected by α-MG. In conclusion, α-MG ameliorated learning and memory deficits in both acute and sub-acute treatments in CCH rats by improving the spatial learning but not hippocampal LTP. Hence, α-MG may be a promising lead compound for CCH-associated neurodegenerative diseases, including vascular dementia and Alzheimer's disease.

Acute toxicity profiling of the ethyl acetate fraction of Swietenia macrophylla seeds and in-vitro neuroprotection studies.

Swietenia macrophylla (SM) is a medicinally important plant found in tropical and subtropical regions of the world. The ethyl acetate fraction of the seeds of S. macrophylla (SMEAF) is reported to exhibit potent anticancer, antitumor, anti-inflammatory and antifeedant activities. Till date, there have been no studies reported on the acute oral toxicity profile of the ethyl acetate fraction of the seeds of SM. The objective of the present study was to determine the acute toxicity of SMEAF and evaluate the in-vitro neuroprotective activity of SMEAF using primary neuronal cell cultures. In acute oral toxicity study, the SMEAF did not produce any lethal signs of morbidity and mortality. Histo-pathological findings, support the safety of SMEAF, as there were no significant changes observed in any of the parameters studied. Based on the results obtained in MTT assay, we infer that SMEAF has a significant neuroprotective effect, as it increased the cell viability and exhibited protection to the neuronal cells against TBHP induced oxidative stress. Thus, SMEAF can be suggested for use in the development of herbal drug formulations with neuroprotective potential.