1. Volume 132, Issue 1, Pages 372-383 (January 2007)
Mild Hypothermia Attenuates Liver Injury and Improves Survival in Mice With Acetaminophen Toxicity 
Javier Vaquero, Mireille Bélanger, Laura James, Raquel Herrero, Paul Desjardins, Jean Côté, Andres T. Blei, Roger F. Butterworth 
Gastroenterology 
Volume 132, Issue 1, Pages (January 2007)
DOI: /j.gastro
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2. Figure 1
Effect of body temperature on survival in mice treated with acetaminophen (APAP; 300 mg/kg intraperitoneally). (A) Rectal temperature in control mice (Saline), APAP-treated mice maintained at normothermia (NT), and APAP-treated mice allowed to become mildly hypothermic (mild HT). The body temperature of both NT and mild-HT mice was maintained within normal values in the first 2 hours after APAP challenge. The mean ± SEM of each group is plotted at each time point. (B) Survival rates of NT and mild-HT mice (n = 9–10 per group) in the first 24 hours after APAP challenge. Log-rank test was used for statistical analysis.
Gastroenterology  , DOI: ( /j.gastro )
Copyright © 2007 AGA Institute Terms and Conditions

3. Figure 2
Effect of body temperature on the progression of liver injury in mice after an acetaminophen (APAP) challenge (300 mg/kg intraperitoneally). (A) Percentage area of hepatocyte necrosis in APAP-treated normothermic (NT; open circles) and mildly hypothermic (mild-HT; filled circles) mice. Each point represents the mean percentage area of hepatocyte necrosis in a single mouse, calculated from 6 low-power fields. Horizontal lines represent the mean percentage area of necrosis in each group. (B) Plasma ALT values in saline-treated mice (Sal) and APAP-treated NT (hatched bars) and Mild-HT (filled bars) mice. The number of mice analyzed for each time point is indicated in the abscissa axis. Bars represent mean ± SEM. *P < .001 vs Sal; #P < .05 NT vs mild HT; ##P < .01 NT vs mild HT. (C, D) Representative histological liver sections from mice followed for 24 hours showing hemorrhagic congestion and extensive centrilobular necrosis in NT mice (C) and smaller areas of necrosis in mild-HT mice (D). Hematoxylin-phloxine-saffron. Calibration marks in the lower right are 100 μm.
Gastroenterology  , DOI: ( /j.gastro )
Copyright © 2007 AGA Institute Terms and Conditions

4. Figure 3
Effect of body temperature on the formation of acetaminophen (APAP)-protein adducts and on the depletion of hepatic glutathione stores in mice after an APAP challenge (300 mg/kg intraperitoneally). (A, B) Concentration of (A) APAP-protein adducts and (B) total glutathione (reduced GSH plus oxidized GSSG) in liver tissue of saline-treated mice (Sal), APAP-treated mice maintained at normothermia (NT; hatched bars), and APAP-treated mice allowed to develop mild hypothermia after the first 2 hours of APAP injection (mild HT, filled bars). (C, D) Concentration of APAP-protein adducts (C) and total glutathione (D) in liver tissue when mild hypothermia was allowed to develop immediately after the APAP injection (filled bars). The number of mice analyzed for each time point is indicated in the abscissa axes. Bars represent mean ± SEM. *P < .05 vs Sal; **P < .001 vs Sal; #P < .05 NT vs mild HT.
Gastroenterology  , DOI: ( /j.gastro )
Copyright © 2007 AGA Institute Terms and Conditions

5. Figure 4
Effect of body temperature on hepatic hemorrhagic congestion and hepatic glycogen content in mice after an acetaminophen (APAP) challenge (300 mg/kg intraperitoneally). (A, B) Hepatic hemoglobin (Hb; A) and glycogen (B) content in liver tissue of saline-treated mice (Sal), and APAP-treated normothermic (NT; hatched bars) and hypothermic (mild HT; filled bars) mice. The number of mice analyzed for each time point is indicated in the abscissa axes. Bars represent mean ± SEM. *P < .01 NT vs Sal; **P < .001 vs Sal; #P < .001 NT vs mild HT.
Gastroenterology  , DOI: ( /j.gastro )
Copyright © 2007 AGA Institute Terms and Conditions

6. Figure 5
Representative periodic acid–Schiff-stained liver sections for histological assessment of hepatic glycogen stores in mice after an acetaminophen (APAP) challenge (300 mg/kg intraperitoneally). In fasted mice treated with saline, glycogen stores were observed predominantly around central veins (A). In mice treated with APAP that were maintained at normothermia (NT), periodic acid–Schiff staining was strongly reduced at 2 hours (B) and 4 hours (not shown) and subsequently was increased at 8 hours around portal areas (C). In APAP-treated mice that were allowed to develop mild hypothermia (mild HT), glycogen started to increase around portal areas at 4 hours (not shown) and was strongly increased over basal levels at 8 hours (D). Calibration marks in the lower right are 100 μm.
Gastroenterology  , DOI: ( /j.gastro )
Copyright © 2007 AGA Institute Terms and Conditions

7. Figure 6
Evaluation of apoptosis in mice after an acetaminophen (APAP) challenge (300 mg/kg intraperitoneally). (A) Western blot analysis of poly(ADP-ribose) polymerase (PARP) expression at 8 hours and 12 hours in liver from saline-treated mice (Sal), and APAP-treated normothermic (NT) and hypothermic (mild HT) mice. Whole protein liver extracts (50 μg per lane) were resolved on 8% sodium dodecyl sulfate–polyacrylamide gels. Liver protein from a mouse treated with Fas-agonistic antibody was used as positive control. The 85-kDa band corresponding to the proteolytic cleavage of PARP was visible only in NT mice. No cleavage of PARP was observed at 4 hours in any group (not shown). Actin is shown as loading control. (B) Quantification of hepatocytes positive for terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling (TUNEL) in liver sections from saline-treated mice and from APAP-treated NT and mild-HT mice at 12 hours after APAP challenge. Graph shows the average number of TUNEL-positive hepatocytes per low-power field (LPF) in each group (n = 6–9 per group). Bars represent mean ± SEM. *P < .05 vs Sal and mild HT; #P < .05 vs Sal and NT. (C) High-power field of a representative TUNEL-stained liver section from an APAP-treated mouse. Notice the presence of hepatocytes with distinct nuclear staining and others with staining of both nucleus and cytosol. Calibration mark in the lower right is 20 μm.
Gastroenterology  , DOI: ( /j.gastro )
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8. Figure 7
Hepatocyte DNA synthesis evaluated by BrdU immunohistochemistry in mice after an acetaminophen (APAP) challenge (300 mg/kg intraperitoneally). (A) Quantification of hepatocyte DNA synthesis in liver sections from saline-treated mice and APAP-treated mice maintained at normothermia (NT; hatched bars) or allowed to develop mild hypothermia (mild HT; filled bars). Graph shows the average number of BrdU positively stained hepatocyte nuclei per low-power field (LPF) in each group (n = 5–9 per group). Bars represent mean ± SEM. *P < .01 vs Sal; **P < .001 vs Sal; #P < .001 NT vs mild HT. (B) Relationship between body temperature, extent of liver injury, and liver regeneration in NT (open circles) and mild HT (filled circles) mice surviving 48 hours after the APAP challenge. Data points represent the percentage area of hepatocyte necrosis in individual mice (assessed in hematoxylin-phloxine-saffron stained liver sections), plotted against the average number of BrdU–labeled hepatocyte nuclei per low-power field of BrdU immunohistochemistry liver sections. The dotted line represents the linear regression line. (C, D) Representative photomicrographs of BrdU immunohistochemistry in an NT and a mild-HT mouse killed 48 hours after the injection of APAP. Arrows indicate BrdU–labeled hepatocyte nuclei. Calibration mark in the lower right is 100 μm.
Gastroenterology  , DOI: ( /j.gastro )
Copyright © 2007 AGA Institute Terms and Conditions