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Objective To evaluate the relationship between the expression of microRNA-146a (miR-146a) in liver tissue and the inflammatory hepatic injury induced by ischemia/reperfusion (I/R) in rats. Methods One hundred and forty-four Sprague-Dawley (SD) rats were randomly divided into three groups: control (group N), sham operation (group S) and group I/R. Each group was subdivided into four subgroups (n = 12), and different substances were respectively injected intravenously to rats in different subgroups at 1 hour before the experiment: 220 μL physiological saline (group A), 20 μL miR-146a mimic + 200 μL physiological saline (group B), 20 μL miR-146a mimic + 200 μL ultrasound microbubble contrast agent (group C) and 20 μL miR-146a inhibitor + 200 μL ultrasound microbubble contrast agent (group D). Before the experiment and after experiment for 24 hours, the plasma concentrations of alanine aminotransferase (ALT), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected, the reverse transcription-polymerase chain reaction (RT-PCR) was used to measure the expression of miR-146a in liver tissue, and Western Blot was applied to detect protein expressions of Toll-like receptor 4 (TLR4), IL-1 receptor associated kinase 1 (IRAK-1), IL-6 and TNF-α, and the pathological hepatic cell injury was observed. Results Before the experiment and 24 hours after experiment in various subgroups of N and S groups, there were no statistical significant differences in the plasma concentrations of ALT, IL-6 and TNF-α, and the expression of miR-146a level and the protein expressions of TLR4, IRAK-1, IL-6 and TNF-α in liver tissues; the pathological examination also did not show any obvious hepatic cell injury. After the experiment for 24 hours: compared to the group S, the liver tissue miR-146a expression was significantly decreased in the subgroups A and D of group I/R (miR-146a/U6nsRNA: 0.51±0.13, 0.22±0.09 vs. 1.01±0.02, both P < 0.01), and the plasma concentrations of ALT, IL-6 and TNF-α and the protein expressions of TLR4, IRAK-1, IL-6 and TNF-α in liver tissues were significantly increased [ALT (U/L): 103.23±26.64 vs. 44.16±18.55, 176.46±7.26 vs. 49.74±6.83, IL-6 (μg/L): 64.28±16.19 vs. 17.68±7.54, 88.49±3.23 vs. 15.58±2.38; TNF-α (μg/L): 31.28±2.57 vs. 5.58±3.35, 59.12±8.74 vs. 5.27±1.37; TLR4/GAPDH: 2.43±0.36, 3.23±0.71 vs. 0.96±0.24, IRAK-1/GAPDH: 2.34±0.52, 3.14±0.63 vs. 0.76±0.21, IL-6/GAPDH: 1.01±0.22, 1.11±0.16 vs. 0.98±0.37, TNF-α/GAPDH: 2.05±0.48, 2.86±0.27 vs. 0.59±0.16, all P < 0.01], moreover, the hepatic pathological lesions were obvious; the liver tissue expression of miR-146a was significantly increased after being transfected with miR-146a mimic in subgroups B and C of group I/R (miR-146a/U6nsRNA: 1.56±0.31, 2.40±0.53 vs. 1.01±0.02, both P < 0.01), especially in group C combined with ultrasound microbubble (P < 0.01). However, the protein expressions of TLR4, IRAK-1, IL-6 and TNF-α in liver tissues were significantly decreased (TLR4/GAPDH:0.77±0.18, 0.65±0.27 vs. 0.96±0.24, IRAK-1/GAPDH: 0.61±0.14, 0.47±0.20 vs. 0.76±0.21, IL-6/GAPDH:0.80±0.13, 0.54±0.22 vs. 0.98±0.37, TNF-α/GAPDH: 0.41±0.14, 0.16±0.03 vs. 0.59±0.16; all P < 0.01), and the expressions were more significant in the group C combined with ultrasound microbubbles (P < 0.01), and the hepatic pathological damage was mild, however, the plasma concentrations of ALT, IL-6 and TNF-α were of no statistical significant differences. Conclusion Ultrasound microbubble can efficiently transfect miR-146a mimic and inhibitor into the liver tissue, and miR-146a may negatively regulate the I/R inflammatory liver injury mediated by TLR signaling pathway.
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Objective To investigate the changes of plasma ghrelin,growth hormone (GH) and growth hormone releasing hormone (GHRH) and gastric ghrelin in patients with chronic obstructive pulmonary disease( COPD ) and to explore their clinical significances.Methods Plasma ghrelin,GH,GHRH,TNFα,IL-6 and C reactive protein (CRP) were measured in 40 COPD patients and 20 controls with chronic bronchitis. Correlated factors of plasma ghrelin,TNFα,IL-6,CRP were analyzed. Body composition was assessed with bioelectrical impedance analysis.The expression of gastric ghrelin in patients with COPD was detected.Results Plasma ghrelin was higher in the underweight patients than in the normal weight patients and in the controls [ ( 1.78 ± 0.46 ) ng/L,( 1.39 ± 0.46 ) ng/L,( 1.36 ± 0.39 ) ng/L,respectively].Plasma GH was lower in the underweight patients than in the normal weight patients and in the controls [(4.12 ±0.83) μg,/L,(5.17 ±0.72) μg/L,(6.49 ± 1.13) μg/L,respectively].Plasma GHRH was lower in the underweight patients than in the normal weight patients and in the controls [ (20.43 ± 4.41 ) ng/L,(23.47 ± 3.97) ng/L,( 27.48 ± 10.06) ng/L,respectively ].Plasma ghrelin was higher in the underweight patients than in the controls ( P ＜ 0.01 ).Plasma ghrelin was higher in the underweight patients than in the normal weight patients with COPD.Plasma ghrelin (log transformed) was negatively correlated with BMI and percentage of body fat in the COPD patients.Plasma GHRH was positively correlated with ghrelin in the underweight patients ( r =0.515,P ＜ 0.05 ),while no correlation was found between plasma G H and ghrelin in the underweight patients (r =0.415,P ＞ 0.05 ).Plasma ghrelin was positively correlated with TNFα and IL-6 in the underweight patients.The gastric expression of ghrelin showed no evident difference between the patients with COPD and the controls.Conclusions The plasma GH in COPD patients may not be correlated with ghrelin.The plasma ghrelin level may be a useful indicator for malnutrition in COPD patients.Plasma ghrelin might be involved in the pathogenesis of CODP by affecting the body energy metabolism.
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Objective To explore the expression of sterol regulatory element binding protein 1C (SREBP-1C) and glucose-regulated protein 94(GRP-94)in hyperhomocysteinmia and to evaluate the effects of endoplasmic reticulum stress proteins on hepatocytes lipids metabolism. Methods After hyperhomocysteinmia C57BL/6 mice model being induced by high methionine diet, TGE and CHO of Hepatocytes were determined, and the expression of SREBP-1C and GRP-94 was assessed by RT-PCR and Western blot. All data were compared to those in control group′s. Results The level of plasmic homocysteine(Hcy) and hepatocytes TGE or CHO of high methionine diet mice at different time point significantly ascended(P
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AIM:To explore the effect of homocysteine (Hcy)-mediated endoplasmic reticulum stress on lipid metabolism in hepatocytes.METHODS: HepG2 cells used in the study were treated with 5 mmol/L Hcy. The concentrations of Hcy, triglycerides (TGE) and cholesterol (CHO) in the cells were measured. In high methionine diet-induced hyperhomocysteinemia C57BL/6 mice, the concentrations of TGE and CHO in hepatocytes were analyzed. The mRNAs and proteins expressions of glucose-regulated protein 78 (GRP-78) and sterol regulatory element binding protein (SREBP-1) were also assessed.RESULTS: The concentrations of Hcy and lipids (TGE, CHO) in HepG2 cells at different time point were elevated after treated with 5 mmol/L Hcy (P0.05,vs 0 week). The mRNAs and proteins expressions of GRP-78 and SREBP-1 in mice at different time point after high methionine diet were higher than that at 0 week (P