1-Furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) is a chemically synthesized novel compound with a propenone moiety.A recent study demonstrated that FPP-3 could inhibit lipopolysaccharide-stimulated production of nitric oxide and tumor necrosis factor-a in the cultures of RAW 264.7 macrophages.1) In addition, FPP-3 could not only inhibit cyclooxygenase (COX) and 5-lipoxygenase activities but also inhibit COX-2 by 35-times more selectively than COX-1.2) p.o.) significantly suppressed the carrageen-induced paw edema in rats and, most importantly, there were no gastric ulcers formed in FPP-3-treated rats and mice, whereas indomethacin caused gastric mucosal bleeding in a dose-dependent manner.
3)In our previous studies, two metabolites were identified in rat liver cytosol and microsomal fractions in the presence of NADPH by a liquid chromatography-electrospray tandem mass spectrometry (LC/ESI-MS) and 1 H-NMR as M1, 1-furan-2-yl-3-pyridin-2-yl-propan-1-one, and M2, 1-furan-2-yl-3-pyridin-2-yl-propan-1-ol. 4) Moreover, FPP-3 and two metabolites were detected in rat sera by high-performance liquid chromatography with ultraviolet detection.
5)Further investigation on in vivo metabolism of FPP-3 was essential for the development of FPP-3 as an anti-inflammatory drug. The objective of our present study was to characterize in vivo metabolic pathway of FPP-3. The phase 1 and 2 metabolites of FPP-3 were identified by using LC/ESI-MS in male Sprague-Dawley rats.
MATERIALS AND METHODSMaterials FPP-3 (purity, Ͼ99.8%) used in this study was chemically synthesized in our group.2) Metabolites were separated by thin layer chromatography (TLC) in our group. TLC alumina sheets (silica gel 60 F 254 ), ethyl acetate (EtOAc) and acetonitrile (ACN) were HPLC-grades from Merck Ltd. (Poole, U.K.). Formic acid was obtained from Aldrich Chemical Co. (Milwaukee, U.S.A.). All other chemicals were of analytical grade and used as received.Animals Specific pathogen-free male Sprague-Dawley rats were obtained from Orient Co. (Seoul, Korea). The animals received at 5-6 weeks of age were acclimated for at least 1 week. Upon arrival, animals were randomized and housed 3 per cage. The animal quarters were strictly maintained at 23Ϯ3°C and 50Ϯ10% relative humidity. A 12 h light and dark cycle was used with an intensity of 150-300 lux. All animal procedures were followed based on a guideline recommended by the Society of Toxicology (Reston, VA, U.S.A.) in 1989.Urinary and Fecal Extraction Animals were treated intravenously in penile vein with FPP-3 at 4 mg/kg in sterile saline and housed individually in metabolic cages equipped with urine and feces separators. Urine and feces from the test animals were collected and weighed at the following intervals: 0 to 12, 12 to 24 and 24 to 48 h. Four volumes of 50% ACN were added to fecal samples, followed by a homogenization. After centrifugation at 3000 g for 10 min, the supernatant was collected. The samples were stored immediately at Ϫ20°C.For the characterization of phase 1 metabolite, the urinary and fecal s...