Crosstalk between angiogenesis, cytokeratin-18, and insulin resistance in the progression of non-alcoholic steatohepatitis

Figure 1 Representative microphotographs of CD34-positive neovessels and cytokeratin-18 (CK-18)-positive cells in the liver of patients. A: Marked CD34-positive immunopositive vessels could be found in NASH along with liver fibrosis development; B: The immunopositivity of CK-18 was mainly observed in the hepatocytes. The arrows indicate CD34 and CK-18-immunopositivity in A and B, respectively. The original magnification was × 100.

Figure 2 Semi-quantitative analysis of CD34 and possible correlation with liver fibrosis development. A: Semi-quantitative analysis of the CD34-positive neovessels in the liver in non-alcoholic fatty liver disease (NAFLD). There was no difference between the control healthy liver and simple FL. In NASH, a marked augmentation of neovascularization was found in the liver of NASH as compared with FL. The magnitude of neovascularization in high-grade (F2 to F4) liver fibrosis was more than in low-grade (F0, F1) fibrosis. The proportional increase in neovascularization was almost parallel to the development of liver fibrosis. ^bP < 0.01 vs control group; ^dP < 0.01 vs low-grade fibrosis with NASH group. The number of patients in each group was as follows: Control (n = 3), FL (n = 11), low-grade fibrosis (F0 and F1: n = 10), and high-grade fibrosis (F2 to F4: n = 18). MV: Microvessel density; B: The relationship between the development of CD-34-positive vessels and fibrosis grade in NAFLD. The degree of angiogenesis correlated with the development of fibrosis. The equation was y = 509.82x - 6.7958. The correlation coefficient was 0.6288.

Figure 3 Semi-quantitative analysis of the CK-18-positive cells in the liver (A) and HOMA-IR (B) in NAFLD. Similar to the CD34-positive neovascularization, there was no difference between the control healthy liver and FL. In NASH, a marked augmentation of CK-18 (A) and HOMA-IR (B) was found in the liver of NASH as compared with FL. The magnitude of neovascularization in high-grade (F2 to F4) liver fibrosis was more than in low-grade (F0, F1) fibrosis. The number of patients in each group was as follows; C (n = 3), FL (n = 11), low-grade fibrosis (F0 and F1: n = 10), and high-grade fibrosis (F2 to F4: n = 18). ^bP < 0.01 vs control group; ^dP < 0.01 vs low-grade fibrosis with NASH group.

Figure 4 The relationship between angiogenesis, CK-18-positive vessels (A), and HOMA-IR (B). The degree of angiogenesis correlated with the CK-18-positive cells (A) and HOMA-IR (B). A: The magnitude of expression of CK-18 correlated positively with CD34-positive neovascularization. The equation was y = 500.63x + 4.6606. The correlation coefficient was 0.6512; B: Similarly, there was a positive correlation between HOMA-IR and hepatic neovascularization. The equation was y = 233.75x - 339.39. The correlation efficient was 0.6184.