title: High-throughput screening assays for cyclooxygenase-2 and 5-lipoxygenase, the targets for inflammatory disorders.
abstract: High-throughput screening (HTS) involves testing of compound libraries against validated drug targets using quantitative bioassays to identify 'hit' molecules that modulate the activity of target, which forms the starting point of a drug discovery effort. Eicosanoids formed via cyclooxygenase (COX) and lipoxygenase (LOX) pathways are major players in various inflammatory disorders. As the conventional non-steroidal anti-inflammatory drugs (NSAIDs) that inhibit both the constitutive (COX-1) and the inducible (COX-2) isoforms have gastric and renal side effects and the recently developed COX-2 selective anti-inflammatory drugs (COXIBs) have cardiac side effects, efforts are being made to develop more potent and safer antiinflammatory drugs. Current assay methods for these enzymes, such as oxygraphic, radioisotopic, spectrophotometric etc. are not compatible for screening of large number of compounds as in drug discovery programs. In the present study, HTS-compatible assays for COX-1, COX-2 and 5-LOX were developed for screening of compound libraries with the view to identify potential anti-inflammatory drug candidates. A spectrophotometric assay involving co-oxidation of tetramethyl-p-phenylene diamine (TMPD) during the reduction of prostaglandin G2 (PGG2) to PGH2 was adopted and standardized for screening of compounds against COX-1 and COX-2. Similarly, the HTS-compatible FOX (ferrous oxidation-xylenol orange) based spectrophotometric assay involving the formation of Fe3+/xylenol orange complex showing absorption in the visible range was developed for screening of compounds against 5-LOX.
authors: Department of Animal Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
authors: K Anil
authors: KA
authors: Kumar
authors: T Chandramohan
authors: TC
authors: Reddy
authors: Gorla V
authors: GV
authors: Reddy
authors: D Bharat Kumar
authors: DB
authors: Reddy
authors: S V K
authors: SV
authors: Mahipal
authors: Sudhir
authors: S
authors: Sinha
authors: Anil N
authors: AN
authors: Gaikwad
authors: P
authors: P
authors: Reddanna
mesh_terms: D000818:Animals; D001094:Arachidonate 5-Lipoxygenase / Q000378:metabolism*; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D007249:Inflammation / Q000188:drug therapy / Q000201:enzymology*; D020128:Inhibitory Concentration 50; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D018411:Spodoptera
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D016859:Lipoxygenase Inhibitors; D001094:Arachidonate 5-Lipoxygenase; D051546:Cyclooxygenase 2