肝纤维化的基因治疗

Expression of α-adrenergic receptor (AR), β1-AR and β2-AR in liver tissue of nonalcoholic fatty liver disease rats

AIM: To investigate the expression of α-adrenergic receptor (α-AR), β₁-AR and β₂-AR in liver tissue of nonalcoholic fatty liver disease (NAFLD) rats.

METHODS: An NAFLD model was developed by feeding a high-fat diet. HE staining was used to determine hepatic morphological changes. Western blot and real-time Q-PCR were used to measure the dynamic changes of α-AR, β₁-AR, and β₂-AR protein and mRNA expression, respectively, during the development process of NAFLD.

RESULTS: HE staining showed that NAFLD was induced successfully in rats. Western blot analysis showed that the protein expression of α-AR, β₁-AR and β₂-AR increased with the progression of NAFLD (P < 0.05). Real-time Q-PCR analysis showed that the α-AR, β₁-AR and β₂-AR mRNA expression increased with the progression of NAFLD, too (P < 0.01).

CONCLUSION: The expression of α-AR, β₁-AR, and β₂-AR increases at both protein and mRNA levels during the developmental process of NAFLD.

Effect of norepinephrine on expression of leptin and leptin receptor in hepatic stellate cells

AIM: To investigate the effect of sympathetic neurotransmitter norepinephrine (NE) on the expression of leptin and leptin receptor in hepatic stellate cells (HSCs) in vitro.

METHODS: Different concentrations of NE were applied on HSCs for 24, 48 or 72 h. Immunohistochemical staining was used to detect the expression of α-smooth muscle actin (α-SMA) in activated HSCs. Western blot was used to detect the expression of leptin and soluble leptin receptor (sOB-R) proteins. Real-time PCR was used to examine the effect of NE on mRNA expression of leptin and sOB-R in HSCs.

RESULTS: Immunohistochemistry results showed that after 1, 10, or 100 μmol/L NE was used on HSCs, the expression of α-SMA increased significantly at 24 h (14.1 ± 4.4, 17.5 ± 5.2, 19.8 ± 4.1 vs 11.3 ± 4.5; P < 0.05), suggesting that NE could activate HSCs and promote their proliferation. When 10 μmol/L NE was applied for 24, 48 or 72 h, α-SMA expression gradually increased (17.5 ± 5.2; 18.5 ± 5.4; 19.2 ± 6.2, P < 0.05), indicating that NE induced HSC proliferation in a time-dependent manner. Western blot analysis showed that leptin protein expression was significantly higher in HSCs after treatment with 1, 10 and 100 μmol/L NE for 24 h compared with the control group (1.54 ± 0.08, 2.72 ± 0.09, 2.84 ± 0.18 vs 0.85 ± 0.12, P < 0.05); the expression of leptin receptor protein was also significantly higher than that in the control group (1.57 ± 0.18, 2.51 ± 0.17, 2.89 ± 0.19 vs 0.98 ± 0.15, P < 0.05). Real-time PCR was used to detect mRNA expression of leptin and leptin receptor, and the results showed that leptin mRNA expression was significantly higher than that in the control group (1.51 ± 0.08, 2.58 ± 0.09, 3.63 ± 0.12 vs 1.00 ± 0.07, P < 0.05); the expression of leptin receptor mRNA was also significantly higher than that in the control group (1.71 ± 0.08, 2.87 ± 0.10, 4.01 ± 0.14 vs 1.00 ± 0.08, P < 0.05).

CONCLUSION: The sympathetic neurotransmitter NE plays a role in the process of liver fibrosis possibly by promoting leptin and sOB-R expression in activated HSCs.

Effects of salidroside on expression of ROCK in rats with liver fibrosis

AIM: To observe the effects of salidroside on the expression of ROCK in liver tissue of CCl₄-induced liver fibrosis in rats, and to explore its probable mechanism.

METHODS: Ninety healthy SD rats were randomly divided into 3 groups: control group (n = 10), salidroside group (n = 40) and liver fibrosis group (n = 40). Experimental liver fibrosis was induced by (with the concentration of 300 mL/L soluted in liquid paraffin) subcutaneous injection of CCl₄ (at the dosage of 3 mL/kg, twice per wk, 8 wks). The salidroside was injected into the peritoneal cavity at the dosage of 5 mg/kg, twice per week for 8 weeks. Liver tissues from each group were stained with Masson and HE staining to observe the collagen deposition. Expressions of ROCKⅠand ROCKⅡ in the liver tissue were detected with in situ hybridization (ISH) and immunohistochemistry (IH) respectively. All the figures were scanned with electronic computer, and the data were analyzed with Image-Plus software.

RESULTS: A significant collagen deposition and rearrangement of the parenchyma were noted in liver tissue of CCl₄-treated rats. There were lots of pseudolobule in liver tissue. The semiquantitative histological scores and average area of collagen were significantly increased when compared with control rats (2.1 ± 0.3 vs 3.6 ± 0.8, 74.82 ± 21.51 μm²vs 290.86 ± 89.37 μm², both P < 0.05). Compared with control group, the expressions of ROCKⅠ, ROCKⅡ and ROCKⅠmRNA, ROCKⅡmRNA were decreased significantly in salidroside group (0.203 ± 0.068 vs 0.357 ± 0.182, 0.237 ± 0.056 vs 0.394 ± 0.238; 0.197 ± 0.019 vs 0.394 ± 0.238, 0.185 ± 0.031 vs 0.279 ± 0.112, P < 0.05 or 0.01).

CONCLUSION: The expressions of ROCKⅠand ROCKⅡ in liver tissues are inhibited significantly with salidroside treatment. Salidroside could interfere with the signal transduction of Rho-ROCK pathway and then inhibit liver fibrosis in rats.