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.
MATERIALS AND METHODS: Male rats were rendered diabetes mellitus via intraperitoneal injection of streptozotocin and nicotinamide. Following diabetes development, wound was created at the back of the neck. 1% and 2% mangiferin gel and 1% silver sulphurdiazine (SS) gel (positive control) were applied to the wound for twenty-one (21) days. Fasting blood glucose (FBG) levels were weekly monitored. At the end of the treatment, rats were sacrificed and wound was excised and subjected for histopathological and molecular biological analysis.
RESULTS: No changes to serum FBG levels was noted throughout the period of mangiferin treatment. Albeit, a significant decrease in the size of the wound with increased in the skin thickness of surrounding the wound were observed. Increased expression and distribution of EGF, FGF, TGF-β, VEGF, PI3K, MMP and Nrf2 and decreased expression and distribution of TNFα and NF-κB p65 were observed in diabetic wound treated with topical mangiferin.
CONCLUSIONS: Mangiferin has potential to be used as an agent to promote wound healing in diabetic condition.