Inhibitory effect of the compounds isolated from Rhus verniciflua on aldose reductase and advanced glycation endproducts

The aim of this paper was to evaluate active principles for diabetic complications from Rhus verniciflua. Nine compounds were isolated via bioactivity guided fractionation and isolation and tested for their effects on recombinant human aldose reductase and advanced glycation endproducts. Butein and sulfuretin isolated from ethyl acetate fraction were found to possess strongly both forms of aldose reductase and advanced glycation endproducts inhibition. The inhibitory activity of butein against a recombinant human aldose reductase (IC50 value: 0.5 mu M) was 2.6 times more potent that of epalrestat as a positive control (IC50 value: 1.3 mu M). The inhibitory potency of sulfuretin (IC50 value: 124.7 mu M) on advanced glycation end-products was about 10 times more potent that of aminoguanidine as a positive control (IC50 value: 1231.0 mu M). These compounds all displayed antioxidative activity which was measured by Photochem(R) apparatus. It was concluded, therefore, butein and sulfuretin have antioxidative as well as aldose reductase and advanced glycation endproducts inhibitory effects. As a result, these compounds could be proposed as a leading compound for further study as a new natural products drug that could be used for diabetic complications.