title: Spatial-temporal distribution of nitric oxide involved in regulation of phenylalanine ammonialyase activation and Taxol production in immobilized Taxus cuspidata cells.
abstract: The generation of nitric oxide (NO) in Taxus cuspidata in immobilized support matrices and the potential role of NO as signal molecular in regulation of Taxol production were investigated. It was found that the immobilization induced a spatial and temporal-dependent NO burst in immobilized supported matrices. NO level reached the maximum in the central zone of immobilized supported matrices on day 20, which was more than twice compared with that in suspended cells. Further investigations showed that the phenylalanine ammonialyase (PAL) activity and Taxol production of the 20-day-old immobilized T. cuspidata cells increased by onefold and 11% after 4h treatment with 20 microM NO donor (sodium nitroprusside), respectively. NO inhibitor N(omega)-nitro-L-arginine and NO scavenger 2-phenyl-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxyde partially blocked PAL activity and Taxol accumulation in immobilized cells. These results suggest that NO plays a signal role in regulation of PAL activity and Taxol production in immobilized T. cuspidata cells.
authors.affiliation: Department of Pharmaceutical Engineering, Key Laboratory of Systems Bioengineering, Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin, PR China.
authors.forename: Wen-Hai
authors.initials: WH
authors.lastname: Xiao
authors.forename: Jing-sheng
authors.initials: JS
authors.lastname: Cheng
authors.forename: Ying-Jin
authors.initials: YJ
authors.lastname: Yuan
mesh_terms: D000704:Analysis of Variance; D018914:Cells, Immobilized / Q000166:cytology / Q000378:metabolism*; D016166:Free Radical Scavengers / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000494:pharmacology; D017239:Paclitaxel / Q000378:metabolism*; D010650:Phenylalanine Ammonia-Lyase / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D020946:Taxus / Q000166:cytology / Q000378:metabolism*
chemical_list: D016166:Free Radical Scavengers; D020030:Nitric Oxide Donors; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D010650:Phenylalanine Ammonia-Lyase; D017239:Paclitaxel