f action was investigated by testing for involvement of NF ��B, MAP kinases and TLR2. Methods General e perimental design As an inflammatory environment is thought to be present in patients with discogenic back pain, human intervertebral disc cells were pretreated with recombinant IL 1B, thus increasing the levels of proinflammatory cytokines and matri de grading enzymes. Thereafter, different solvents were used to prepare sequential curcuma e tracts and tested for their ability to reduce inflamma tory and catabolic Cilengitide gene e pression after 6 hours. The presumably most abundant bioactive substance in the most potent e tract was chosen based on structure based solubility, information in the literature and identi fication using HPLC MS analysis and tested in the same setting, using various concentrations.
A mechanistic investigation, looking at involvement of the NF ��B, MAP kinase and TLR2 pathway, was per formed for curcumin as well. Human intervertebral disc cell culture Human intervertebral disc tissue was removed from 27 patients under going spinal surgery for discectomy or interbody fusion for degenerative disc disease or disc herniation. Informed consent was obtained from all patients prior to surgery in accordance with the institutional review board. Intervertebral disc cells were released from the tissue by enzymatic digestion with 0. 2% collagenase NB4 and 0. 3% dispase II in PBS for appro i mately 4 hours. After digestion, the tissue suspension was filtered, washed and cells were seeded and e panded in DMEM F12 supplemented with 10% FCS, penicillin, streptomycin and ampicillin, with medium changes once to twice a week and e pansion up to passage 2 or 3.
Preparation of curcuma e tracts Organic curcuma from McCormick was used to prepare sequential DMSO and ethanol e tracts. Briefly, curcuma was dispersed in DMSO at a concentra tion of 320 mg ml, incubated on the shaker at room temperature for 10 min and centrifuged at 2000 rpm for 10 min before taking off the DMSO fraction. The remaining pellet was then dispersed in 100% ethanol and the procedure was repeated. After removal of the ethanol fraction, the thereafter remaining pellet was discarded. For each e periment, the fractions were prepared freshly in order to avoid any damage due to freezing thawing.
HPLC MS analysis of the curcuma DMSO and EtOH e tracts The DMSO and EtOH e tracts of curcuma were analysed by high performance liquid chromatography, coupled to a mass spectrometer. The chromatography of the curcuma e tracts was performed according to Wichitnithad et al, using a RP C18 column. For identification of the curcuminoids, measurements were carried out with a multimode source ionization mode positive mode. drying gas flow 12 l min. drying gas temperature 350 C. nebulizer pressure 50 psig. fragmentor voltage 70 V. capillary voltage 4000 V. The quantification of the most abundant curcuminoids was done at a wave length of 425 nm, with commercially available curcumin as an e ternal standar