Neuroprotective and Antiherpetic Properties of Polyphenolic Compounds from Heartwood.

In this study, we isolated a new isoflavanostilbene maackiapicevestitol () as a mixture of two stable conformers and as well as five previously known dimeric and monomeric stilbens: piceatannol (), maackin (), scirpusin A (), maackiasine (), and maackolin () from heartwood, using column chromatography on polyamide, silicagel, and C-18. The structures of these compounds were elucidated by NMR, HR-MS, and CD techniques. Maksar obtained from heartwood and polyphenolics - possessed moderate anti-HSV-1 activity in cytopathic effect (CPE) inhibition and RT-PCR assays. A model of PQ-induced neurotoxicity was used to study the neuroprotective potential of polyphenolic compounds from . Maksar showed the highest neuroprotective activity and increased cell viability by 18% at a concentration of 10 μg/mL. Maackolin () also effectively increased the viability of PQ-treated Neuro-2a cells and the value of mitochondrial membrane potential at concentrations up to 10 μΜ. Maksar and compounds - possessed higher FRAP and DPPH-scavenging effects than quercetin. However, only compounds and at concentrations of 10 μM as well as Maksar (10 μg/mL) statistically significantly reduced the level of intracellular ROS in PQ-treated Neuro-2a cells.