Decrease of Protease-Resistant PrP Level in ScN2a Cells by Polyornithine and Polyhistidine.

Based on previous studies reporting the anti-prion activity of poly--lysine and poly--arginine, we investigated cationic poly--ornithine (PLO), poly--histidine (PLH), anionic poly--glutamic acid (PLE) and uncharged poly--threonine (PLT) in cultured cells chronically infected by prions to determine their anti-prion efficacy. While PLE and PLT did not alter the level of PrP, PLO and PLH exhibited potent PrP inhibition in ScN2a cells. These results suggest that the anti-prion activity of poly-basic amino acids is correlated with the cationicity of their functional groups.

Application of Centrifugal Partition Chromatography for Bioactivity-Guided Purification of Antioxidant-Response-Element-Inducing Constituents from Atractylodis Rhizoma Alba.

Activity-guided separation of antioxidant response element (ARE)-inducing constituents from the rhizomes of Atractylodis Rhizoma Alba was performed by the combination of centrifugal partition chromatography (CPC) and an ARE luciferase reporter assay. From 3 g of the active -hexane fraction, one polyacetylene, (6,12)-tetradeca-6,12-dien-8,10-diyne-1,3-diyl diacetate (47.3 mg), and two sesquiterpenes, atractylenolide I (40.