Rosemary (Rosmarinic Acid)

Rosmarinic acid (RosA) is a naturally occurring ester of caffeic acid and 3,4-dihydroxyphenyllactic acid. It is widely distributed in Labitae herbs, which include rosemary, sweet basil, and perilla. RosA has a broad range of applications that include use as a food preservative, in cosmetics, and medicinal uses as an antimicrobial and an antioxidant. In addition, it has been reported that RosA has the ability to block complement fixation and inhibit lipoxygenase and cyclooxygenase activity. Recently, the inhibition of T-cell receptor (TCR)-mediated signaling has been identified as one of the many effects of anti-inflammatory drugs. Despite the fact that their points of action are quite different, nonsteroidal anti-inflammatory drugs (NSAIDs) such as tacrolimus, pimecrolimus and hydroxychloroquine have been found to inhibit TCR-induced signaling events, including Ca2+ mobilization, activation of p38 mitogen-activated protein kinase (MAPK), and expression of the CD40 ligand. Similarly, RosA was recently found to inhibit the Ca2+− dependent pathways by which TCR-mediated signaling occurs by inhibiting PLC-γ1 and Itk activities. In addition, the results of many studies evaluating the anti-inflammatory and immunomodulatory effects of RosA have suggested that it has many beneficial and healthpromoting effects.