induction of quinone reductase and heat shock protein 70 by some phytochemicals

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Abstracts / Toxicology 240 (2007) 164–192 171 Induction of quinone reductase and heat shock protein 70 by some phytochemicals Ahmed Hamed , Andrew Wilkinson, Waisun Kok, Jeffrey Fry School of Biomedical Sciences, Medical School, University of Nottingham, Nottingham NG7 2UH, UK E-mail address: [email protected] (A. Hamed). Medicinal and edible plants have been considered as rich sources of cancer-chemopreventive phytochemicals and there is a growing interest in identifying phytochem- icals which have multiple cytoprotective properties. In a previous report (Hamed and Fry, 2006), we have shown the ability of sulforaphane (SN), a well-known chemo- preventive phytochemical, to induce heat shock protein 70 (HSP70) and quinone reductase (QR) in rat (FGC4) and murine (hepa1c1c7) hepatoma cell lines, respec- tively. The aim of this work is to test other QR-inducing phytochemicals (Curcumin (CM) and Indole-3-carbinol (I3C); Kang and Pezzuto, 2004) for their potential mul- tiple cytoprotective effects. Cultured FGC4 and hepa1c1c7 cells were exposed to different concentrations of CM or I3C for 24 h after which cells were lysed and the cytosolic fraction pre- pared from these lysates. Toxicity of the phytochemicals was tested in an identical set of experiments using neutral red uptake assay to determine the maximum non-toxic dose for each phytochemical. QR activities in hepa1c1c7 cell lysates were monitored kinetically using dichlorophenolindophenol (DCPIP) reduction assay. The effect of CM or I3C on the QR and HSP70 expres- sion was monitored by Western blotting using 10 g total protein per lane. As summarized in Table 1, SN produced a significant induction of QR activity and expression in hepa1c1c7 cells at non-toxic concentration of 25 M. Also, the treatment of hepa1c1c7 cells with I3C (100 M) and Table 1 Effect of SN, I3C and CM on QR activity, QR expression and HSP70 expression (QR in hepa1c1c7 cells; HSP70 in FGC4 cells) QR activity (%) QR protein (%) HSP70 protein (%) SN (25/12.5 M) 380 ± 20 ** 430 ± 143 * 220 ± 19 * I3C (100 M) 260 ± 20 ** 210 ± 30 * 72 ± 17 CM (25 M) 260 ± 25 ** 256 ± 6 * 77 ± 5 Data are means ± S.E.M. (% to relevant control) of at least three exper- iments. Where indicated, values in treated cells are significantly greater than those in control cells at * P < 0.05, ** P < 0.01 (ANOVA, Dunnett’s test). CM (25 M) revealed significant induction of QR activity and expression. The treatment of FGC4 cells with I3C and CM produced no increase of the expression of HSP70 protein at non-toxic concentration whilst treatment of FGC4 with SN (12.5 M) elicited a signif- icant up-regulation of HSP70 expression. However, CM caused a significant induction of HSP70 (220% ± 32, relevant to control) at the toxic concentration of 100 M. The results indicate that the multiple cytoprotective effects of SN are not matched by I3C and CM. The cellu- lar response to CM at 100 M (up-regulation of HSP70) appears to be a consequence of its toxicity at this concen- tration. Further work will be directed towards elucidating the mechanism of HSP70 induction by SN, and towards the study of additional plant products for their potential multiple cytoprotective effects. References Hamed, A., Fry, J, 2006. Planta Med. 72, 1055. Kang, Y., Pezzuto, J.M., 2004. Methods Enzymol. 382, 380–414. doi:10.1016/j.tox.2007.06.050 Comparison of gene expression changes in whole pancreas with isolated pancreatic acinar cells of rats fed diets containing Wyeth 14,643 or ammonium perfluorooctanoate Simon M. Plummer 1 , David G. Farrar 2 , Clifford R. Elcombe 1 1 CXR Biosciences Ltd., James Lindsay Place, Dundee, UK; 2 Ineos Chlor, Runcorn, Cheshire, UK E-mail address: [email protected] (S.M. Plummer). The non-genotoxin APFO (300 ppm in the diet) has been shown to induce pancreatic acinar cell tumours in rats Biegel et al. (2001). In order to identify pancre- atic gene expression changes associated with pancreatic carcinogenesis in ‘target’ cells for this process male Sprague–Dawley rats (6–7 weeks old) were fed either (1) the potent pancreatic carcinogen Wyeth 14,643 (Wy) in the diet at 50 ppm (carcinogenic dose) or (2) APFO at 300 ppm for up to 4 weeks. Transcriptional profiling analysis at 1, 7 and 28 days, using a rat whole genome 60 mer oligonucleotide array containing 44,000 genes was performed on purified preparations of pancreatic acinar cells. Pancreatic acinar cells were purified using a method involving collagenase digestion and centrifugation through BSA (10%). Immunohis-

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Page 1: Induction of quinone reductase and heat shock protein 70 by some phytochemicals

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Abstracts / Toxico

nduction of quinone reductase and heat shockrotein 70 by some phytochemicals

hmed Hamed, Andrew Wilkinson, Waisun Kok,effrey Fry

School of Biomedical Sciences, Medical School,niversity of Nottingham, Nottingham NG7 2UH, UK

-mail address: [email protected] (A. Hamed).

Medicinal and edible plants have been considered asich sources of cancer-chemopreventive phytochemicalsnd there is a growing interest in identifying phytochem-cals which have multiple cytoprotective properties. In arevious report (Hamed and Fry, 2006), we have shownhe ability of sulforaphane (SN), a well-known chemo-reventive phytochemical, to induce heat shock protein0 (HSP70) and quinone reductase (QR) in rat (FGC4)nd murine (hepa1c1c7) hepatoma cell lines, respec-ively. The aim of this work is to test other QR-inducinghytochemicals (Curcumin (CM) and Indole-3-carbinolI3C); Kang and Pezzuto, 2004) for their potential mul-iple cytoprotective effects.

Cultured FGC4 and hepa1c1c7 cells were exposedo different concentrations of CM or I3C for 24 h afterhich cells were lysed and the cytosolic fraction pre-ared from these lysates. Toxicity of the phytochemicalsas tested in an identical set of experiments usingeutral red uptake assay to determine the maximumon-toxic dose for each phytochemical. QR activities inepa1c1c7 cell lysates were monitored kinetically usingichlorophenolindophenol (DCPIP) reduction assay.he effect of CM or I3C on the QR and HSP70 expres-ion was monitored by Western blotting using 10 �g totalrotein per lane.

As summarized in Table 1, SN produced a significantnduction of QR activity and expression in hepa1c1c7ells at non-toxic concentration of 25 �M. Also, thereatment of hepa1c1c7 cells with I3C (100 �M) and

able 1ffect of SN, I3C and CM on QR activity, QR expression and HSP70xpression (QR in hepa1c1c7 cells; HSP70 in FGC4 cells)

QR activity(%)

QR protein(%)

HSP70protein (%)

N (25/12.5 �M) 380 ± 20** 430 ± 143* 220 ± 19*

3C (100 �M) 260 ± 20** 210 ± 30* 72 ± 17M (25 �M) 260 ± 25** 256 ± 6* 77 ± 5

ata are means ± S.E.M. (% to relevant control) of at least three exper-ments. Where indicated, values in treated cells are significantly greaterhan those in control cells at *P < 0.05, **P < 0.01 (ANOVA, Dunnett’sest).

(2007) 164–192 171

CM (25 �M) revealed significant induction of QRactivity and expression. The treatment of FGC4 cellswith I3C and CM produced no increase of the expressionof HSP70 protein at non-toxic concentration whilsttreatment of FGC4 with SN (12.5 �M) elicited a signif-icant up-regulation of HSP70 expression. However, CMcaused a significant induction of HSP70 (220% ± 32,relevant to control) at the toxic concentrationof 100 �M.

The results indicate that the multiple cytoprotectiveeffects of SN are not matched by I3C and CM. The cellu-lar response to CM at 100 �M (up-regulation of HSP70)appears to be a consequence of its toxicity at this concen-tration. Further work will be directed towards elucidatingthe mechanism of HSP70 induction by SN, and towardsthe study of additional plant products for their potentialmultiple cytoprotective effects.

References

Hamed, A., Fry, J, 2006. Planta Med. 72, 1055.Kang, Y., Pezzuto, J.M., 2004. Methods Enzymol. 382, 380–414.

doi:10.1016/j.tox.2007.06.050

Comparison of gene expression changes in wholepancreas with isolated pancreatic acinar cells of ratsfed diets containing Wyeth 14,643 or ammoniumperfluorooctanoate

Simon M. Plummer 1, David G. Farrar 2, Clifford R.Elcombe 1

1 CXR Biosciences Ltd., James Lindsay Place, Dundee,UK; 2 Ineos Chlor, Runcorn, Cheshire, UK

E-mail address: [email protected](S.M. Plummer).

The non-genotoxin APFO (300 ppm in the diet) hasbeen shown to induce pancreatic acinar cell tumours inrats Biegel et al. (2001). In order to identify pancre-atic gene expression changes associated with pancreaticcarcinogenesis in ‘target’ cells for this process maleSprague–Dawley rats (6–7 weeks old) were fed either(1) the potent pancreatic carcinogen Wyeth 14,643(Wy) in the diet at 50 ppm (carcinogenic dose) or (2)APFO at 300 ppm for up to 4 weeks. Transcriptionalprofiling analysis at 1, 7 and 28 days, using a ratwhole genome 60 mer oligonucleotide array containing

∼44,000 genes was performed on purified preparationsof pancreatic acinar cells. Pancreatic acinar cells werepurified using a method involving collagenase digestionand centrifugation through BSA (10%). Immunohis-