RESUMEN
Zingiber cassumunar Roxb. was previously shown to possess potent anti-inflammatory activity. We investigated the effect of its ethanol extract on hyaluronan (HA), an extracellular matrix compound with proinflammatory activity synthesis in human oral fibroblasts. Cultured fi broblasts were treated at various times with different concentrations of the extract (0.1-50 μg/mL) with or without retinoic acid (RA; 10 μM), or left untreated as a control. Culture medium was analyzed for HA quantities by the ELISA-based assay. Total RNA was harvested and RT-PCR analyses were performed to determine mRNA expression of hyaluronan synthase (HAS) -1, -2, and –3. Z. cassumunar extract, at 25 and 50 μg/mL, with or without 10 μM of RA, significantly decreased HA levels (p \< 0.05). Consistent with decreased HA levels, mRNA expression of HAS-2, but not HAS-1 or HAS-3, was selectively down-regulated by the extract. Collectively, these data indicate that the ethanol extract of Z. cassumunar inhibits HA synthesis in human oral fibroblasts, which may be involved in chronic inflammatory disorders, particularly in the oral cavity.