Inhibition of COX-2 expression in PMA differentiated THP-1 macrophages by extracts of Epipremnum pinnatum

COX-2 is a mediator of inflammation and highly expressed in diseased conditions like rheumatoid arthritis, asthma and several autoimmune diseases. Since many anti-inflammatory agents on the market treating these diseases cause severe side effects, natural sources offer a great pool for discovering novel lead compounds targeting COX-2 [1].

Epipremnum pinnatum (L.) Engl. (Araceae) is traditionally used as an analgesic and anti-inflammatory agent in various areas of Asia [2]. Little is known about the mode of action and the chemical composition of this plant. With a PMA differentiated, LPS stimulated THP-1 inflammation model [3], we evaluated the influence of leaf extracts (hexan, dichlormethan, methanol) on COX-2 gene expression. At the concentration of 20 µg/mL, the methanol extract showed potent COX-2 mRNA inhibition (54.3% +/- 9.2). Extracts prepared by two different extraction methods (ASE, Soxhlet) were compared and showed similar inhibition of COX-2 gene expression.

We could demonstrate for the first time that the methanol extract of Epipremnum pinnatum exerts strong COX-2 gene expression inhibition in vitro. The observed effect may help us to understand the traditional use of Epipremnum pinnatum and possibly lead to identification and isolation of novel COX-2 gene expression inhibitors.

References:

[1] Tsatsanis C, Androulidaki A, Venihaki M, Margioris A N. Signalling networks regulating cyclooxygenase-2. The International Journal of Biochemistry & Cell Biology 2006; 38: 1654 – 1661

[2] Zumbroich T J. To strengthen the teeth and harden the gums – teeth blackening as medicinal practice in Asia, Micronesia and Melanesia. Ethnobotany Research & Applications 2011; 9: 97 – 113

[3] Galasso S, Pacifico S, Kretschmer N, Pan S, Marciano S, Piccolella S, Monaco P, Bauer R. Influence of seasonal variation on Thymus longicaulis C. Presl chemical composition and its antioxidant and anti-inflammatory properties. Phytochemistry 2014; 107: 80 – 90