Effects of polydatin on ALT, AST, TNF-alpha, and COX-2 in sepsis model mice / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the protective effects of polydatin on sepsis-induced acute liver injury (ALI) in mice, and to preliminarily study its mechanisms.</p><p><b>METHODS</b>The sepsis model was established using cecal ligation and puncture (CLP).A sham-operation control group was also set up. Polydatin (50, 100, and 300 mg/kg, respectively) was administrated to mice 1 h before CLP. The survival and liver injury were evaluated subsequently per 6 h after CLP. The survived mice were scarified 24 h later. The serum and the liver tissue sample were collected. The serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were detected by colorimetric method. The content of tumor necrosis factor-alpha (TNF-alpha) was assayed by ELISA. The cyclooxygenase-2 (COX-2) expression in the liver tissue was detected by Western blot. The pathological changes of the hepatic tissue were analyzed by hematoxylin and eosin stain.</p><p><b>RESULTS</b>The mortality of mice reached as high as 50% at 24 h after CLP. The biochemical indices and the pathological changes of the liver tissue showed obvious lesion. The success rate of modeling was 90%. Compared with the sham-operation control group, the serum ALT,AST activity, the TNF-alpha content, and the hepatic COX-2 protein expression markedly increased in the CLP group (P < 0.01). Polydatin improved the sepsis-induced mortality dose-dependently, inhibited increased ALT, AST activity and TNF-alpha, decreased the hepatic COX-2 protein expression, and attenuated the pathological injury of the liver (P < 0.05).</p><p><b>CONCLUSION</b>Polydatin could effectively protect sepsis-induced ALI, which might be achieved possibly through inhibiting serum TNF-alpha production and hepatic COX-2 expression.</p>

Resolvin E1 protects against ox-LDL-induced injury on vascular endothelial cells / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate whether Resolvin E1 (RvE1) could protect against ox-LDL-induced injury on human vein vascular endothelial cells and reveal related molecular mechanisms.</p><p><b>METHODS</b>Human vein vascular endothelial cells were randomly assigned to six groups, which were treated with saline, RvE1, wortmanin, ox-LDL, ox-LDL and RvE1, ox-LDL and RvE1 and wortmanin, respectively. After 48 h, survival rates were determined by MTT, apoptosis rate of cells were determined by flow cytometry, TNF-α contents were assayed by ELISA, caspase 3 and 9 activities were measured by microplate reader, and the expression of p-AKT and LOX-1 were determined by Western blot.</p><p><b>RESULT</b>Compared with normal saline group, survival rate was markedly decreased and apoptosis rate, TNF-α content, caspase 3 and 9 activities, and the expression of LOX-1 were significantly increased in ox-LDL group (P < 0.01). Survival rate was significantly increased and apoptosis rate, TNF-α content, caspase 3 and 9 activities, and the expression of LOX-1 were significantly decreased in ox-LDL + RvE1 group compared to ox-LDL group (P < 0.01), these beneficial effects of RvE1 could be blocked by PI3K inhibitor wortmanin (P < 0.05).</p><p><b>CONCLUSION</b>The present data showed that RvE1 could effectively protect against ox-LDL-induced endothelial cell injury, which might be mediated by PI3K-AKT signaling pathway.</p>

Lipoxin A4 negatively regulates lipopolysaccharide-induced differentiation of RAW264.7 murine macrophages into dendritic-like cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Lipoxins (LXs), endogenous anti-inflammatory and pro-resolving eicosanoids generated during various inflammatory conditions, have novel immunomodulatory properties. Because dendritic cells (DCs) play crucial roles in the initiation and maintenance of immune response, we determined whether LXs could modulate the maturation process of DCs and investigated the effects of lipoxin A(4) (LXA(4)) on lipopolysaccharide (LPS)-induced differentiation of RAW264.7 cells into dendritic-like cells.</p><p><b>METHODS</b>RAW264.7 cells were cultured in vitro with 1 microg/ml LPS in the absence or presence of LXA(4) for 24 hours, and cellular surface markers (MHC-II, CD80 (B7-1), CD86 (B7-2)) were measured by flow cytometry (FCM). Mixed lymphocyte reaction was performed to evaluate the allostimulatory activity. Cytoplastic IkappaB degradation and nuclear factor kappa B (NF-kappaB) translocation were detected by Western blotting. Luciferase reporter plasmid was transiently transfected into RAW264.7 cells, and luciferase activity was determined to measure the transcriptional activity of NF-kappaB.</p><p><b>RESULTS</b>LXA(4) reduced the ratio of LPS-treated RAW264.7 cells to DCs with morphological characteristics and inhibited the expression of MHC II. LPS-induced up-regulation of CD86 was moderately suppressed by LXA(4) but no obvious change of CD80 was observed. Moreover, LXA(4) weakened the allostimulatory activity of LPS-treated RAW264.7 cells. These alterations of LPS+LXA(4)-treated cells were associated with a marked inhibition of IkappaB degradation, NF-kappaB translocation and then the transcriptional activity of NF-kappaB.</p><p><b>CONCLUSIONS</b>LXA(4) negatively regulates LPS-induced differentiation of RAW264.7 cells into dendritic-like cells. This activity reveals an undescribed mechanism of LXA(4) to prevent excessive and sustained immune reaction by regulating maturation of DCs.</p>

Inhibitiory action of asiaiticoside on collagen-induced arthritis in mice / 药学学报

The study is to investigate the effect of asiaticoside on collagen-induced arthritis (CIA). The model of CIA mice was prepared and the change of secondary paw swelling and the arthritis scores were observed. In vitro proliferation of spleen cells was examined using MTT assay. The cell-free protein extracts from the arthritic joints and nonarthritic joints were used for the analysis of protein expression of cyclooxygenase-2 (COX-2). And the level of PGE2 in joints was assayed using PGE2 express EIA kit. The tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) levels in the serum were measured by ELISA. Histopathological examination was performed by hematoxylin-eosin (HE) stain method. Asiaticoside (10, 20 and 40 mg x kg(-1) x d(-1), 22 d, ig) significantly reduced paw swelling, and decreased the arthritis scores. There was a significant reduction in proliferation of spleen cells of CIA mice treated with asiaticoside as compared with that of untreated CIA mice. COX-2, PGE2, TNF-alpha and IL-6 production in CIA mice were inhibited by asiaticoside. Meanwhile, the pathological examination showed that articular cartilage degeneration with synovial hyperplasia and inflammatory cells infiltration in CIA mice was suppressed by asiaticoside. Its active mechanism may be related to inhibiting proliferation of lymphocyte and reduction of expression of COX-2 and inflammatory cytokines.

Effect of tetramethylpyrazine on lipopolysaccharides induced macrophage cyclo-oxidase-2 expression and apoptosis of cardiac myocytes / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effect of tetramethylpyrazine (TMP) on lipopolysaccharides (LPS) induced macrophage cyclo-oxidase-2 (COX-2) gene expression and activity in RAW264.7 mice, and to further investigate the effect and mechanism of TMP on LPS induced apoptosis of cardiac myocytes in suckling mice.</p><p><b>METHODS</b>RT-PCR and Western Blot (WB) were used to investigate the macrophage COX-2 gene expression, ELISA was used to measure its activity, fluorescence microscopy was used to determine the apoptosis of murine neonatal cardiac myocyte, and fluorescence spectrophotometry was used to detect the concentration of intracellular calcium ion (Ca2+).</p><p><b>RESULTS</b>TMP of 10(-6) mol/L could significantly reduce the COX-2 mRNA and protein expression (P < 0.05), in 10(-5) mol/L and 10(-4) mol/L could significantly decrease the COX-2 expression (P < 0.01) stimulated by LPS, but couldn't influence the activity of COX-2 by different TMP concentration. TMP in 10(-5) mol/L could significantly lower the concentration of intracellular Ca2+ in cardiac myocyte, and antagonize the LPS induced apoptosis of cardiac myocyte in suckling mice (P < 0.05).</p><p><b>CONCLUSION</b>TMP has the pharmacological effect in inhibiting LPS induced macrophage COX-2 expression and apoptosis of cardiac myocyte in suckling mice.</p>