Potential of rosmarinic acid from Orthosiphon aristatus extract for inflammatory induced diseases and its mechanisms of action

Orthosiphon aristatus has been traditionally used as a medicinal herb for various illnesses in Southeast Asia and Europe. The most dominant bioactive compound of the herb is rosmarinic acid (RosA) which has been demonstrated for its remarkable anti-inflammatory properties. This review describes the recent progress of studies on multi-target molecular pathways of RosA in relation to targeted inflammatory-associated diseases. An inclusive literature search was conducted using electronic databases such as Google Scholar, Scopus, Springer Link, PubMed, Medline, Wiley and Science Direct for studies reporting on the anti-inflammatory actions of RosA from 2008 until 2023. The keywords of the search were RosA and anti-inflammatory in relation to hepatoprotective, chondroprotective, cardioprotective, neuroprotective and toxicity. Only publications that are written in English are included in this review. The inhibition and deactivation of pro-inflammatory biomolecules by RosA were explained based on the initial inflammation stimuli and their location in the body. The activation of Nrf2/HO-1 expression to inhibit NF-κB pathway is the key mechanism for hepatoprotection. Besides NF-κB inhibition, RosA activates PPARγ to alleviate ischemia/reperfusion (I/R)-induced myocardial injury for cardioprotection. The regulation of MAPK and T-cell activation is important for chondroprotection, whereas the anti-oxidant property of RosA is the main contributor of neuroprotection. Even though less studies on the anti-inflammation of RosA extracts from O. aristatus, but the effective pharmacological properties of RosA has promoted it as a natural potent lead for further investigation.