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Adaptation to acetaminophen exposure elicits major changes in expression and distribution of the hepatic proteome.

Eakins R, Walsh J, Randle L, Jenkins RE, Schuppe-Koistinen I, Rowe C, Starkey Lewis P, Vasieva O, Prats N, Brillant N, Auli M, Bayliss M, Webb S, Rees JA, Kitteringham NR, Goldring CE, Park BK - Sci Rep (2015)

Bottom Line: Acetaminophen overdose is the leading cause of acute liver failure.Genetic ablation of a master regulator of cellular defence, NFE2L2, has little effect, suggesting redundancy in the regulation of adaptation.These data reveal unexpected complexity and dynamic behaviour in the biological response to drug-induced liver injury.

View Article: PubMed Central - PubMed

Affiliation: MRC Centre for Drug Safety Science, University of Liverpool, Liverpool L69 3GE, UK.

ABSTRACT
Acetaminophen overdose is the leading cause of acute liver failure. One dose of 10-15 g causes severe liver damage in humans, whereas repeated exposure to acetaminophen in humans and animal models results in autoprotection. Insight of this process is limited to select proteins implicated in acetaminophen toxicity and cellular defence. Here we investigate hepatic adaptation to acetaminophen toxicity from a whole proteome perspective, using quantitative mass spectrometry. In a rat model, we show the response to acetaminophen involves the expression of 30% of all proteins detected in the liver. Genetic ablation of a master regulator of cellular defence, NFE2L2, has little effect, suggesting redundancy in the regulation of adaptation. We show that adaptation to acetaminophen has a spatial component, involving a shift in regionalisation of CYP2E1, which may prevent toxicity thresholds being reached. These data reveal unexpected complexity and dynamic behaviour in the biological response to drug-induced liver injury.

No MeSH data available.


Related in: MedlinePlus

Widespread changes in protein abundance occur in rat liver following repeated acetaminophen exposure.(a–d) Volcano plots of all common proteins quantified by iTRAQ analysis, at each time-point (a) 24 h, (b) 48 h, (c) 72 h, (d) 96 h, relative to vehicle control. A complete list is provided in Supplementary Tables 1a–d. Coloured circles represent differential expression (blue - raw P value, p < 0.05; red – FDR, p ≤ 0.05). (e) Principal Components Analysis identified the greatest differences between single and repeat dose samples. (f ) Heat map representing the 1169 proteins common to all samples and all time-points identified distinct changes in protein abundance in repeat-dosed animals (red indicates increased abundance, blue indicates decreased abundance). (g) Western blots for GSTP1, NQO1, PCNA and VIM, performed in order to validate proteomic findings. Representative blots of two rats at each time-point are shown. Actin was used as a loading control.
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f2: Widespread changes in protein abundance occur in rat liver following repeated acetaminophen exposure.(a–d) Volcano plots of all common proteins quantified by iTRAQ analysis, at each time-point (a) 24 h, (b) 48 h, (c) 72 h, (d) 96 h, relative to vehicle control. A complete list is provided in Supplementary Tables 1a–d. Coloured circles represent differential expression (blue - raw P value, p < 0.05; red – FDR, p ≤ 0.05). (e) Principal Components Analysis identified the greatest differences between single and repeat dose samples. (f ) Heat map representing the 1169 proteins common to all samples and all time-points identified distinct changes in protein abundance in repeat-dosed animals (red indicates increased abundance, blue indicates decreased abundance). (g) Western blots for GSTP1, NQO1, PCNA and VIM, performed in order to validate proteomic findings. Representative blots of two rats at each time-point are shown. Actin was used as a loading control.

Mentions: Global changes at each time-point were visualised as volcano plots (Fig. 2a–d), in which significance (y) is plotted against fold change (x). Although changes can be seen at 24 h (Fig. 2a), at 48 h (Fig. 2b; peak toxicity) the volcano plots show the greatest change in protein abundance, as indicated by the number of blue points (raw p < 0.05) and red points (FDR ≤0.05). Large numbers of protein changes are still observed at 72 h (Fig. 2c) and 96 h (Fig. 2d). Principal Component (PC) analysis was performed to identify the proteins contributing to the clearest differences in the data set as a whole (Fig. 2e). Comparing PC1 to PC4 allowed separation into three distinct groups (in Fig. 2e, see control and 24 h to the top right, 48 h and 72 h to top left, and 96 h to the bottom of the plot), thereby identifying groups of proteins contributing to the major differences between these groups (Fig. 2e). These proteins are listed in Supplementary Table 2. Numerical descriptions of significant changes are shown in Table 1.


Adaptation to acetaminophen exposure elicits major changes in expression and distribution of the hepatic proteome.

Eakins R, Walsh J, Randle L, Jenkins RE, Schuppe-Koistinen I, Rowe C, Starkey Lewis P, Vasieva O, Prats N, Brillant N, Auli M, Bayliss M, Webb S, Rees JA, Kitteringham NR, Goldring CE, Park BK - Sci Rep (2015)

Widespread changes in protein abundance occur in rat liver following repeated acetaminophen exposure.(a–d) Volcano plots of all common proteins quantified by iTRAQ analysis, at each time-point (a) 24 h, (b) 48 h, (c) 72 h, (d) 96 h, relative to vehicle control. A complete list is provided in Supplementary Tables 1a–d. Coloured circles represent differential expression (blue - raw P value, p < 0.05; red – FDR, p ≤ 0.05). (e) Principal Components Analysis identified the greatest differences between single and repeat dose samples. (f ) Heat map representing the 1169 proteins common to all samples and all time-points identified distinct changes in protein abundance in repeat-dosed animals (red indicates increased abundance, blue indicates decreased abundance). (g) Western blots for GSTP1, NQO1, PCNA and VIM, performed in order to validate proteomic findings. Representative blots of two rats at each time-point are shown. Actin was used as a loading control.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4660393&req=5

f2: Widespread changes in protein abundance occur in rat liver following repeated acetaminophen exposure.(a–d) Volcano plots of all common proteins quantified by iTRAQ analysis, at each time-point (a) 24 h, (b) 48 h, (c) 72 h, (d) 96 h, relative to vehicle control. A complete list is provided in Supplementary Tables 1a–d. Coloured circles represent differential expression (blue - raw P value, p < 0.05; red – FDR, p ≤ 0.05). (e) Principal Components Analysis identified the greatest differences between single and repeat dose samples. (f ) Heat map representing the 1169 proteins common to all samples and all time-points identified distinct changes in protein abundance in repeat-dosed animals (red indicates increased abundance, blue indicates decreased abundance). (g) Western blots for GSTP1, NQO1, PCNA and VIM, performed in order to validate proteomic findings. Representative blots of two rats at each time-point are shown. Actin was used as a loading control.
Mentions: Global changes at each time-point were visualised as volcano plots (Fig. 2a–d), in which significance (y) is plotted against fold change (x). Although changes can be seen at 24 h (Fig. 2a), at 48 h (Fig. 2b; peak toxicity) the volcano plots show the greatest change in protein abundance, as indicated by the number of blue points (raw p < 0.05) and red points (FDR ≤0.05). Large numbers of protein changes are still observed at 72 h (Fig. 2c) and 96 h (Fig. 2d). Principal Component (PC) analysis was performed to identify the proteins contributing to the clearest differences in the data set as a whole (Fig. 2e). Comparing PC1 to PC4 allowed separation into three distinct groups (in Fig. 2e, see control and 24 h to the top right, 48 h and 72 h to top left, and 96 h to the bottom of the plot), thereby identifying groups of proteins contributing to the major differences between these groups (Fig. 2e). These proteins are listed in Supplementary Table 2. Numerical descriptions of significant changes are shown in Table 1.

Bottom Line: Acetaminophen overdose is the leading cause of acute liver failure.Genetic ablation of a master regulator of cellular defence, NFE2L2, has little effect, suggesting redundancy in the regulation of adaptation.These data reveal unexpected complexity and dynamic behaviour in the biological response to drug-induced liver injury.

View Article: PubMed Central - PubMed

Affiliation: MRC Centre for Drug Safety Science, University of Liverpool, Liverpool L69 3GE, UK.

ABSTRACT
Acetaminophen overdose is the leading cause of acute liver failure. One dose of 10-15 g causes severe liver damage in humans, whereas repeated exposure to acetaminophen in humans and animal models results in autoprotection. Insight of this process is limited to select proteins implicated in acetaminophen toxicity and cellular defence. Here we investigate hepatic adaptation to acetaminophen toxicity from a whole proteome perspective, using quantitative mass spectrometry. In a rat model, we show the response to acetaminophen involves the expression of 30% of all proteins detected in the liver. Genetic ablation of a master regulator of cellular defence, NFE2L2, has little effect, suggesting redundancy in the regulation of adaptation. We show that adaptation to acetaminophen has a spatial component, involving a shift in regionalisation of CYP2E1, which may prevent toxicity thresholds being reached. These data reveal unexpected complexity and dynamic behaviour in the biological response to drug-induced liver injury.

No MeSH data available.


Related in: MedlinePlus