Comparative neuroprotective, anti-inflammatory and neurite outgrowth activities of extracts of king oyster mushroom, Pleurotus eryngii (Agaricomycetes)

• Main Authors: Kushairi, Naufal, Phan, Chia Wei, Sabaratnam, Vikineswary, Vidyadaran, Sharmili, Naidu, Murali, David, Pamela
• Format: Article
• Published: Begell House Inc 2020
• Subjects: QD Chemistry; QH301 Biology; RM Therapeutics. Pharmacology
• Online Access: http://eprints.um.edu.my/37074/
• Institution: Universiti Malaya

Pleurotus eryngii (king oyster mushroom) is a renowned culinary mushroom with various medicinal properties that may be beneficial for health maintenance and disease prevention. However, its effect on the nervous system remains elusive. In this study, hot water (PE-HWA) and ethanol (PE-ETH) extracts of P. eryngii were investigated and compared for their neuroprotective, anti-inflammatory, and neurite outgrowth activities in vitro. Based on the results, both extracts up to 400 mu g/mL were nontoxic to PC12 cells and BV2 microglia (p > 0.05). Treatment with 250 mu M hydrogen peroxide (H2O2) markedly (p < 0.0001) reduced the PC12 cell viability to 67.74 +/- 6.47%. Coincubation with 200 mu g/mL and 400 mu g/mL of PE-ETH dose-dependently increased the cell viability to 85.34 +/- 1.91% (p < 0.001) and 98.37 +/- 6.42% (p < 0.0001) respectively, while PE-HWA showed no activity. Nitric oxide (NO) released by BV2 microglia was notably (p < 0.0001) increased by 1 mu g/mL lipopolysaccharides (LPS) from 7.46 +/- 0.73 mu M to 80.00 +/- 3.78 mu M indicating an inflammatory reaction. However, coincubation with 200 and 400 mu g/mL of PE-ETH significantly (p < 0.0001) reduced the NO level to 58.57 +/- 6.19 mu M and 52.86 +/- 3.43 mu M respectively, while PE-HWA was noneffective. PE-ETH and PE-HWA at 40 mu g/mL significantly increased the neurite-bearing cells from 4.70 +/- 3.36% to 13.12 +/- 2.82% (p < 0.01) and 20.93 +/- 5.37% (p < 0.0001) respectively. Pleumtus eryngii, particularly the ethanol extract (PE-ETH) and its potentially bioactive compounds, could be explored as a neurohealth promoting agent, due to its collective neuroprotective, anti-inflammatory, and neurite outgrowth activities.