Fig. 5

The effects of MTL-CEBPA on MCD-induced fatty liver disease. a Histological analysis of liver sections from normal diet and MCD diet-fed animals for (a, upper panels) 4 weeks and (a, lower panels) 6 weeks stained with H&E and Masson’s trichome (magnification: × 20). (a, left panel) Analysis of liver sections from normal diet control animals showed normal architecture with hepatocytes arranged in the form of cords (blue arrow) radiating away from the central vein. The portal trip (red arrow) contained an artery, vein, and the bile duct. Normal distribution of the sinusoidal spaces (yellow arrow) was observed. (a, right panel) Analysis of the liver sections from MCD diet animals revealed steatosis (green arrow) and inflammatory cell infiltration (black arrow). b Serum levels of ALT and AST indicate reduction to near normal levels following 2 weeks of MTL-CEBPA treatment. Bilirubin levels do not continue to increase in the presence of 1 and 3 mg/kg of MTL-CEBPA treatment. ¥ = p(0.0002); * = p(0.002); $ = p(0.003). Histological analysis of liver sections from MCD diet-fed animals treated with NOV340/FLUC (3 mg/kg) and MTL-CEBPA at 0.3 mg/kg; 1.0 mg/kg and 3 mg/kg. c Liver sections stained with H&E and Masson’s trichrome. (magnification: × 20). Analysis of liver sections from MCD + NOV340/FLUC revealed steatosis (green arrow) and inflammatory cell infiltration (black arrow) which was more prominent, when compared with MCD diet at week 6. The liver sections from all MTL-CEBPA-treated groups showed reduced steatosis and inflammatory changes, when compared to animals on MCD diet at week 6. The effect of MTL-CEBPA-51 on fat deposits in the liver. d The liver cryosections from animals administered with all doses of MTL-CEBPA were stained with Oil red O. Staining pattern (d, left panel) at magnification: 20 × 20 showed less staining intensity in all animals treated with MTL-CEBPA. The scoring of Oil red O staining as percentage of the section area stained (d, right panel) showed significant reduction in staining from the treated groups. ¥ = p( < 0.0002). e The effect of MTL-CEBPA treatment on liver triglyceride (TG) in MCD diet mice was also measured to consolidate the significant reduction seen from the Red Oil-O staining. Data are expressed as mean ± SEM when compared to NOV340/FLUC. ¥ = p( < 0.0002). The effect of MTL-CEBPA on myofibrolast and macrophage formation. (f, left panel) Alpha SMA (α-SMA) staining of liver sections comparing animals fed on normal and MCD diet at week 6 and the effects of MTL-CEBPA treatment. (magnification: × 20). The liver sections from animals on normal diet revealed no sign of α-SMA staining. Animals fed on MCD diet showed prominent staining (green arrow), which was significantly reduced in MTL-CEBPA treatment at all concentrations. Scoring of the area as a percentage value (f, right panel) showed significant reduction in staining from animals treated with MTL-CEBPA. (g, left panel) F4/80 staining analysis of liver sections comparing animals on normal vs. MCD diet at week 6 and the effects of MTL-CEBPA treatment at increasing doses (magnification: × 20). The liver section revealed minimal F4/80 staining in the normal diet. More punctate staining was observed in the animals on MCD diet (black arrow). Scoring of the stained area (g, right panel) showed significant reduction in F4/80 at all doses of MTL-CEBPA groups compared to the control groups. Data are expressed as mean ± SEM. * = p (0.0026); ** = p (0.0012); $ = p (0.0006)