Figure 4

Hepatotoxicity induced by BaP. A. Hierarchical clustering of MAPK genes found differentially transcribed compared to the control. Color scale indicates transcription ratios relative to the control. Gene names or annotations are indicated. HSP701A, heat shock protein 701A. Stars indicate significant transcription variations (>1.5-fold in either direction and adjusted p < 0.05). B. (a) TUNEL staining detecting apoptosis-induced DNA damage in hepatocytes in control and in BaP-exposed animals at 24 hours. Arrows indicate apoptotic hepatocytes. Bars = 50 μm. (b) Percentage of TUNEL-positive nuclei in the livers of control and BaP-exposed animals according to the exposure time points. Data are mean ± SE values for 21 sections replicates. Statistical analysis was performed using the Mann–Whitney test, and asterisks indicate a significant difference from the control: *, p < 0.05. C. (a) Hematoxylin-eosine-safran (HES) staining of liver sections from control and X. tropicalis exposed to BaP. Bars = 100 μm. (b) Percentage of pigment area in liver sections of control and BaP exposed animals. Data are mean ± SE values for 21 sections replicates. Statistical analysis was performed using the Mann–Whitney test (n = 3), and asterisks indicate a significant difference from the control: *, p < 0.05.