Cell experiment:

Rutaecarpine is dissolved in DMSO and diluted with appropriate medium before use. COX-1 and COX-2 cDNA-transfected HEK293 cells are prepared. For measuring inhibitory activity on COX-1 and COX-2 by rutaecarpine, cells in 1 mL of culture medium are seeded into each well of 24-well. After culture for 4 days, the supernatants are removed and 250 mL of fresh medium is added to the cells with or without rutaecarpine. After preincubation for 5 h at 37℃, the cells are further incubated at 37℃ for 30 min with 50 mM arachidonic acid. All reactions are stopped by centrifugation at 120 g at 4℃ for 5 min. Concentrations of PGE2 in the supernatant are measured[1].

Animal experiment:

Rats: Rutaecarpine is dissolved in 0.1% carboxymethyl cellulose and diluted with appropriate medium before use. Male Splague-Dawley (SD) rats (180-220 g) are used in the study. Rutaecarpine administered intraperitoneally and, 1 h later, l-carrageenan solution is injected to right hind paw of rats. Paw volumes are measured using plethysmometer 5 h after l-carrageenan injection[1]. Mice: For the antibody response to SRBCs, rutaecarpine is administered at a single dose of 10 mg/kg, 20 mg/kg, 40 mg/kg or 80 mg/kg in 10 mL of 1% povidone solution intravenously. Control animals are given 1% povidone solution at 10 mL/kg. Specific pathogen-free female BALB/c mice are used in the study[3].

Rutaecarpine, an alkaloid of Evodia rutaecarpa, is an inhibitor of COX-2 with an IC50 value of 0.28 μM.

Rutaecarpine has shown a variety of intriguing biological properties such as anti-thrombotic, anticancer, anti-inflammatory and analgesic, anti-obesity and thermoregulatory, vasorelaxing activity, as well as effects on the cardiovascular and endocrine systems[2]. Rutaecarpine inhibits COX-2 and COX-1 dependent phases of PGD2 generation in BMMC in a concentration-dependent manner with an IC50 of 0.28 μM and 8.7 μM, respectively. It inhibits COX-2-dependent conversion of exogenous arachidonic acid to PGE2 in a dose-dependent manner by the COX-2-transfected HEK293 cells[1].

Rutaecarpine showed in vivo anti-inflammatory activity on rat l-carrageenan induced paw edema by intraperitoneal administration[1]. Rutaecarpine significantly decreases the number of antibody-forming cells and causes weight decrease in spleen in a dose-dependent manner. In addition, rutaecarpine administered mice exhibit reduced splenic cellularity, decreased numbers of total T cells, CD4+ cells, CD8+ cells, and B cells in spleen. IL-2, interferon and IL-10 mRNA expressions are suppressed significantly by rutaecarpine treatment. The number of CD4+IL-2+ cells is reduced significantly following administration of mice with rutaecarpine[3].

References:
[1]. Moon TC, et al. A new class of COX-2 inhibitor, rutaecarpine from Evodia rutaecarpa. Inflamm Res. 1999 Dec;48(12):621-5.
[2]. Lee SH, et al. Progress in the studies on rutaecarpine. Molecules. 2008 Feb 6;13(2):272-300.
[3]. Jeon TW, et al. Immunosuppressive effects of rutaecarpine in female BALB/c mice.Toxicol Lett. 2006 Jul 1;164(2):155-66.