Dual Effects of a Combination of Scutellaria baicalensis and Nelumbo nuciferaon Inflammation and Hyperuricemia

This study developed an effective combination of Scutellaria baicalensis and Nelumbo nucifera (SNE) and evaluated its anti-inflammatory and anti-hyperuricemic effects under in vivo conditions. First, the effect of SNE was tested on in vitro xanthine oxidase (XOD) activity. To investigate the anti-inflammatory effect of SNE, nitric oxide (NO) production was detected by Griess assay, and proinflammatory cytokines were measured by enzyme-linked immunosorbent assay in RAW264.7 cells. Next, we examined the effect of SNE on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) production using Western blot analysis. NF-κB transcriptional activity was measured using the NF-κB-SEAP reporter plasmid. To confirm the anti-hyperuricemia effect of SNE, potassium oxonate (PO)-induced mouse model was established, and the serum was used to measure glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, blood urea nitrogen, creatinine, and XOD levels. Through extensive screening for a herbal medicine library, we found that SNE exhibited a potent inhibitory effect on XOD activity. In addition, SNE remarkably inhibited the production of proinflammatory cytokines [e.g., NO, interleukin (IL)-1β, and IL-6] in lipopolysaccharide-induced RAW264.7 cells and suppressed the promoter activity of NF-κB. SNE also inhibited iNOS and COX-2 expression. Finally, SNE showed anti-hyperuricemic effects in a mouse model of PO-induced hyperuricemia and did not exhibit any toxicity to liver and kidney functions. SNE, a water extract from a mixture of S. baicalensis and N. nucifera at a ratio of 1:1 (w/w), is a good herbal combination that possesses dual therapeutic activities on inflammation and hyperuricemia.