ABSTRACT
This study aimed to investigate the protective effects of hydrogen rich water on the intestinal ischemia/reperfusion (I/R) injury in a rat intestinal intussusception (II) model. Ninety Sprague-Dawley rats were randomly assigned into three groups (n = 30 per group). In sham group, rats received laparotomy, and the intestine was exposed for 15 minutes without II. In I/R + saline group and I/R + hydrogen group, rats received II after laparotomy and then intestine was relocated 8 hours later, followed by immediately intraperitoneal injection of normal saline and hydrogen rich water (HRW) (5 mL/kg), respectively. One hour later, the intestine was collected for hematoxylin-eosin staining and immunohistochemistry for apoptotic cells and 8-oxo-deoxyguanosine, and blood was harvested for detection of tumor necrosis factor-α, malondialdehyde and superoxide dismutase. Hematoxylin-eosin staining showed the intestinal mucosa was significantly damaged in I/R + saline group, which was markedly attenuated after HRW treatment. The serum tumor necrosis factor-α content increased significantly in I/R + saline group, but HRW treatment reduced serum tumor necrosis factor-α content as compared to I/R + saline group (P < 0.05). Serum malondialdehyde content and 8-oxo-deoxyguanosine positive cells in the intestine increased dramatically after II, but HRW significantly reduced them in I/R+hydrogen group (P < 0.05). In addition, superoxide dismutase activity reduced markedly and apoptotic cells increased in I/R + saline group as compared to sham group, but they HRW increased superoxide dismutase activity and reduced apoptotic cells significantly in I/R + hydrogen group (P < 0.05). Our results indicate hydrogen rich water is able to attenuate II induced intestinal I/R injury via inhibiting intestinal inflammation, attenuating intestinal/serum oxidative stress and reducing apoptotic intestinal cells.
ABSTRACT
OBJECTIVES: Butyrate is well known to induce apoptosis in differentiating intestinal epithelial cells. The present study was designed to examine the role of p38 mitogen-activated protein kinase (MAPK) in butyrate-induced intestinal barrier impairment. METHODS: The intestinal barrier was determined by measuring the transepithelial electrical resistance (TER) in a Caco-2 cell monolayer model. The permeability was determined by measuring transepithelial passage of fluorescein isothiocyanate-conjugated inulin (inulin-FITC). The morphology of the monolayers was examined with scanning electron microscopy. The apoptosis status was determined by annexin V-FITC labeling and flow cytometry. The activity of p38 MAPK was determined by the phosphorylation status of p38 with Western blotting. RESULTS: Butyrate at 5 mM increases the apoptosis rate of Caco-2 cells and induces impairment of intestinal barrier functions as determined by decreased TER and increased inulin-FITC permeability. Butyrate treatment activates p38 MAPK in a concentration- and time-dependent manner. SB203580, a specific p38 inhibitor, inhibits butyrate-induced Caco-2 cell apoptosis. Treatment of SB203580 significantly attenuates the butyrate-induced impairment of barrier functions in the Caco-2 cell monolayer model. CONCLUSIONS: p38 MAPK can be activated by butyrate and is involved in the butyrate-induced apoptosis and impairment of intestinal barrier function. Inhibition of p38 MAPK can significantly attenuate butyrate-induced intestinal barrier dysfunction.
Subject(s)
Apoptosis , Butyrates/adverse effects , Intestinal Absorption , Intestinal Diseases/enzymology , Intestinal Mucosa/enzymology , p38 Mitogen-Activated Protein Kinases/metabolism , Annexin A5/metabolism , Apoptosis/drug effects , Caco-2 Cells , Electric Impedance , Enzyme Inhibitors/pharmacology , Fluorescein-5-isothiocyanate/metabolism , Humans , Imidazoles/pharmacology , Intestinal Absorption/drug effects , Intestinal Diseases/metabolism , Intestinal Mucosa/metabolism , Inulin/metabolism , Permeability , Phosphorylation , Pyridines/pharmacology , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitorsABSTRACT
<p><b>OBJECTIVES</b>To study the expression of nicotinamide phosphoribosyl transferase (Nampt) and vascular endothelial growth factor-A (VEGF-A) in gastric carcinoma and investigate their correlations to clinicopathologic features and prognostic significance.</p><p><b>METHODS</b>The proteins of Nampt and VEGF-A in 68 specimens of gastric carcinoma and 59 specimens normal gastric tissue were detected by immunohistochemistry during January 2000 to December 2004, and the 68 patients were followed up.</p><p><b>RESULTS</b>Nampt protein was detected in the cytoplasm of both tissues, and Nampt in gastric carcinoma (13 ± 5) were significantly higher than that in normal gastric tissue (6 ± 3) (t = 7.46, P < 0.01). The expression of Nampt was correlated to invasive depth (F = 4.693, P = 0.034), lymph node metastasis (F = 4.027, P = 0.049), clinical TNM stage (F = 9.979, P = 0.002), but not to gender, age, tumor location, tumor size, differentiation (P > 0.05). The expression of Nampt is correlated with survival of patients that underwent surgical resection for gastric cancer. The survival rate of patients in negative of Nampt was very higher than that of the positive patients, and its co-expression with VEGF-A showed a trend towards poorer survival. The positive correlation was found between the expression of Nampt and VEGF-A in gastric carcinoma (r = 0.293, P = 0.015).</p><p><b>CONCLUSIONS</b>The expression of Nampt is positively correlated to that of VEGF-A in gastric carcinoma. The correlation between the expression of Nampt and VEGF-A in gastric carcinoma plays an important role cooperatively in carcinogenesis, development and metastasis of gastric carcinoma.</p>