Article

The flavouring phytochemical 2-pentanone reduces prostaglandin production and COX-2 expression in colon cancer cells.

Division of Pharmacognosy, Department of Medicinal Chemistry, Biomedical Centre, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden.
Biological & Pharmaceutical Bulletin (Impact Factor: 1.78). 04/2008; 31(3):534-7. DOI: 10.1248/bpb.31.534
Source: PubMed

ABSTRACT Many phytochemicals found in the diet may prevent colon carcinogenesis by affecting biochemical processes in the colonic mucosa. Inflammation and subsequent elevation of the enzyme cyclooxygenase-2 (COX-2) are two such factors involved in the development of colon cancer, and inhibition of these processes could be important targets for chemoprevention. We have previously shown COX-2 inhibitory activity locally in the colon; e.g. in human fecal water from a group of vegetarians. In this study we focus on 2-pentanone, a frequently occurring compound in common foods such as banana and carrot. The aim was to study the inhibitory effects on prostaglandin production and COX-2 protein expression in tumour necrosis factor-alpha stimulated colon cancer cells (HT29) by radioimmunoassay and Western blotting. 2-Pentanone inhibited both prostaglandin production and COX-2 protein expression in human colon cancer cells. A concentration of 400 mumol/l 2-pentanone inhibited the prostaglandin production by 56.9+/-12.9% which is in the same range as the reference compound NS398 (59.8+/-7.6%). The two highest concentrations of 2-pentanone were further analyzed by Western blot, and 400 micromol/l and 200 micromol/l 2-pentanone resulted in a 53.3+/-9.6% and +/-27.1% reduction of the COX-2 protein levels respectively. Further studies on flavouring compounds, for example 2-pentanone, as colon cancer chemopreventives would be very valuable, and such results may contribute to future dietary recommendations.

1 Follower
 · 
94 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Standardized extraction procedures for herb are as important as their authentication to maintain their quality and ensure their safe use. We had prepared a standardized and purified Scutellaria baicalensis Georgi extract, PF2405, which was enriched with three major components, baicalein, oroxylin A and wogonin. In the present study, we investigated the potential anti-inflammatory effects of PF2405 in vitro and in two different experimental animal models of inflammatory bowel disease. Effect of PF2405 studied in tumor necrosis factor (TNF)-α-induced HT-29 cells in vitro. In vivo experimental colitis models were induced by administration of trinitrobenzene sulfonic acid (TNBS) or dextran sulfate sodium (DSS). PF2405 (50 μg/ml) decreased TNF-α-induced cyclooxygenase (COX)-2 expressions through inhibition of phosphorylation of c-Jun N-terminal kinases and p38 mitogen-activated protein kinase in HT-29 cells. Combination of baicalein (20 μg/ml), oroxylin A (8 μg/ml), and wogonin (2 μg/ml) markedly inhibits TNF-α-induced COX-2 expression when compared with individual components. PF2405 (25 mg/kg b.w.) treatment significantly reduced histopathological severity; suppressed expression of COX-2, TNF-α, and interleukin-1β in TNBS-induced mice. Moreover, PF2405 (25 mg/kg b.w.) has both potent preventive and therapeutic activities in DSS-induced colitis. Collectively, PF2405 shows prominent anti-inflammatory effect that can be used as a new therapeutic approach for intestinal inflammatory disorders.
    Archives of Pharmacal Research 01/2015; DOI:10.1007/s12272-015-0553-3 · 1.75 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Although the Scanning Electron Microscope (SEM) has been in existence for many decades, it cannot be yet regarded as a true quantitative instrument—certainly when applied at the nanoscale. This is due to the presence of carbonaceous deposits at the surface and a poor understanding of the emission of secondary electrons from materials. In this paper, a short review is given of some of the progress made in the efforts to improve quantification in the SEM at York. We present results which strongly suggest that the currently accepted theory, which explains why there is a correlation between the secondary electron yield and the work function of a metal, is incorrect. In addition, we show that the backscattering coefficient from materials can be strongly influenced by surface layers at low primary electron energy. Finally, we present Auger electron spectra, which have been acquired at high speed at high vacuum (10−7mbar) and thus represent a new way to determine the composition of nanostructures in the SEM.
    Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment 07/2011; 645(1):68-73. DOI:10.1016/j.nima.2010.12.133 · 1.32 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Expanding the chemical diversity of microbial fermentation products enables green production of fuel, chemicals, and pharmaceuticals. In recent years, coenzyme A (CoA) dependent chain elongation, resembling the reversed β-oxidation pathway, has attracted interest for its use in producing higher alcohols, fatty acids, and polyhydroxyalkanoate. To expand the chemical diversity of this pathway, we metabolically engineered Escherichia coli to produce 2-pentanone, which is not a natural fermentation product of E. coli. We describe the first demonstration of 2-pentanone synthesis in E. coli by coupling the CoA-dependent chain elongation with the acetone production pathway. By bioprospecting for enzymes capable of efficient hydrolysis of 3-keto-hexanoyl-CoA, production of 2-pentanone increased 20 fold, reaching a titer of 240 mg/L. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3167–3175, 2013
    AIChE Journal 09/2013; 59(9). DOI:10.1002/aic.14086 · 2.58 Impact Factor