Yin J, et al. - Researchers inquired the role of dihydroartemisinin (DHA) in regulating cyclooxygenase (COX)/prostaglandin (PG)E synthase [PGES]/PGE₂ cascade and inflammation in endothelial cells (ECs). In time- and dose-dependent manners, striking upregulation of the mRNA and protein levels of COX-2 was evident following DHA treatment, however, significant downregulation of COX-1 was noted. They observed that in line with the upregulation of 15-hydroxyprostaglandin dehydrogenase (15-PGDH, a key enzyme for prostaglandin degradation), a significant attenuation of PGE₂ levels was obvious after DHA treatment. Overall, DHA played an important role in the regulation of PGE₂ synthesis cascade and inflammation in ECs. These data are suggestive of a potential of DHA for the treatment of inflammatory vascular diseases.