Role of the receptor for advanced glycation end products in hepatic fibrosis

Table 1 Expression of RAGE and ECM-related genes in rats cirrhotic due to BDL and TAA treatment

	Control	BDL	TAA
RAGE	1.00 ± 0.31	3.89 ± 0.92b	1.44 ± 0.47
α-SMA	1.00 ± 0.49	5.60 ± 1.59a	10.39 ± 6.78
Procollagen-α1(I)	1.00 ± 0.99	26.45 ± 3.37d	21.92 ± 8.48
MMP-13	1.00 ± 0.38	3.68 ± 2.50	52.88 ± 25.34a
TIMP-1	1.00 ± 0.46	6.50 ± 1.55b	25.47 ± 15.02

RAGE, α-SMA, procollagen-α1(I), MMP-13, and TIMP-1 transcript levels relative to β2-microglobulin ± SD of four animals per group. Data are expressed as n-fold increase compared to sham-operated and normal rats, respectively.

^aP < 0.05,

^bP < 0.01,

^dP < 0.001 vs normal controls. RAGE: Receptor for advanced glycation end products; ECM: Extracellular matrix; BDL: Bile duct ligation; TAA: Thioacetamide; SMA: Smooth muscle actin; MMP: Matrix metalloproteinase; TIMP: Tissue inhibitor of metalloproteinase.

Table 2 Cell-specific expression of RAGE as determined by immunohistochemistry

	RAGE	CD3	CD68	α-SMA
Normal liver
P	2.8 ± 0.71	3.3 ± 0.7	0.3 ± 0.5	0.8 ± 0.72
L	1.0 ± 0.7	1.5 ± 0.6	0.7 ± 0.6	0.2 ± 0.4
BDL
P	11.1 ± 1.53	13.8 ± 1.2	15.2 ± 1.7	8.1 ± 1.24
L	8.1 ± 1.7	13.2 ± 1.9	13.8 ± 1.6	4.8 ± 1.0
TAA
P	7.3 ± 1.9	8.4 ± 1.1	8.5 ± 1.1	6.8 ± 1.25
L	5.7 ± 1.0	6.6 ± 1.1	6.0 ± 1.1	1.9 ± 0.7

Quantitative analysis of the immunohistochemical co-expression of RAGE with CD3, CD68 and α-SMA in normal controls and livers with cirrhosis due to BDL or TAA-intoxication using double staining immunohistochemistry and image analysis. Mean of cells [%] (± SD) per 10 high power fields. Quantitative assessment as described in material and methods.

¹Mainly endothelial cells in the portal areas;

²Vascular smooth muscle cells, subset of activated HSC;

³Focally highly expressed by proliferating bile duct epithelia;

⁴Mainly around proliferating bile ducts;

⁵Mainly at the portal interface and septa. P: Portal; L: Lobular.

Table 3 Expression of RAGE and ECM-related genes after incubation of HSC with AGE

	BSA	AGE-BSA	CML-BSA
RAGE	1.00 ± 0.14	1.20 ± 0.11	1.26 ± 0.07
TGF-β1	1.00 ± 0.06	1.12 ± 0.21	0.99 ± 0.07
Procollagen-α1(I)	1.00 ± 0.08	1.23 ± 0.06a	1.12 ± 0.19
α-SMA	1.00 ± 0.14	1.20 ± 0.20	1.16 ± 0.04
MMP-13	1.00 ± 0.05	1.09 ± 0.14	0.97 ± 0.09

CFSC-2G HSC were incubated with 50 μg/mL BSA, AGE-BSA, or CML-BSA for 24 h. RAGE, TGF-β1, procollagen-α1(I), α-SMA, and MMP-13 transcript levels are expressed relative to GAPDH and as n-fold increase compared to cells treated with BSA alone (means ± SD of at least three individual experiments).

^aP < 0.05 vs BSA. ECM: Extracellular matrix; HSC: Hepatic stellate cells; AGE: Advanced glycation end product; BSA: Bovine serum albumin; CML: N^ε-(carboxymethyl) lysine; TGF: Transforming growth factor.