AIM: To explore the effect of Astraga/us mongholicus polysaccharide (APS) on gene expression and mitogenactivated protein kinase (MAPK) transcriptional activity in intestinal epithelial cells (IEC). METHODS: I...AIM: To explore the effect of Astraga/us mongholicus polysaccharide (APS) on gene expression and mitogenactivated protein kinase (MAPK) transcriptional activity in intestinal epithelial cells (IEC). METHODS: IEC were divided into control group, lipopolysaccharide (LPS) group, LPS+ 50 μg/mL APS group, LPS+ 100 μg/mL APS group, LPS+ 200 μg/mL APS group, and LPS+ 500 μg/mL APS group. Levels of mRNAs in LPS-induced inflammatory factors, tumor necrosis factor (TNF)-α and interleukin (IL)-8, were measured by reverse transcription-polymerase chain reaction. MAPK protein level was measured by Western blotting. RESULTS: The levels of TNF-α and IL-8 mRNAs were significantly higher in IEC with LPS-induced damage than in control cells. APS significantly abrogated the LPS-induced expression of the TNF-α and IL-8 genes. APS did not block the activation of extracellular signal- regulated kinase or c Jun amino-terminal kinase, but inhibited the activation of p38, suggesting that APS inhibits LPS-induced production of TNF-α and IL-8 mRNAs, possibly by suppressing the p38 signaling pathway.CONCLUSION: APS-modulated bacterial productmediated p38 signaling represents an attractive strategy for prevention and treatment of intestinal inflammation.展开更多
The incidence of obesity has dramatically increased in recent years.Consequently,obesity and associated disorders such as nonalcoholic fatty liver disease constitute a serious problem.Therefore,the contribution of adi...The incidence of obesity has dramatically increased in recent years.Consequently,obesity and associated disorders such as nonalcoholic fatty liver disease constitute a serious problem.Therefore,the contribution of adipose tissue to metabolic homeostasis has become a focus of interest.In this review,we discuss the latest discoveries that support the role of lipids in nonalcoholic fatty liver disease.We describe the common mechanisms(cJun aminoterminal kinases,endoplasmic reticulum stress,unfolded protein response,ceramide,lowgrade chronic inflammation)by which lipids and their derivatives impair insulin responsiveness and contribute to inflammatory liver and promote plaque instability in the arterial wall.Presenting the molecular mechanism of lipid activation of proinflammatory pathways,we attempt to find a link between nonalcoholic fatty liver disease,metabolic syndrome and cardiovascular diseases.Describing the common mechanisms by which lipid derivatives,through modulation of macrophage function,promote plaque instability in the arterial wall,impair insulin responsiveness and contribute to inflammatory liver and discussing the molecular mechanism of lipid activation of proinflammatory pathways,the key roles played by the proliferatoractivated receptor and liver X receptorα,nuclear receptorslipid sensors that link lipid metabolism and inflammation,should be emphasized.Further studies are warranted of antiinflammatory drugs such as aspirin,antiinterleukin6 receptors,immunemodulators(calcineurin inhibitors),substances enhancing the expression of heat shock proteins(which protect cells from endoplasmic reticulum stressinduced apoptosis),and anticJun aminoterminal kinases in welldesigned trials to try to minimize the high impact of these illnesses,and the different expressions of the diseases,on the whole population.展开更多
To determine the mechanism of all trans retinoic acid (ATRA) on growth inhibition in human gastric cancer cells Methods Gastric cancer cell lines: MGC80 3, BGC 823, SGC 7901 and MKN 45 CAT assay, Northern blo...To determine the mechanism of all trans retinoic acid (ATRA) on growth inhibition in human gastric cancer cells Methods Gastric cancer cell lines: MGC80 3, BGC 823, SGC 7901 and MKN 45 CAT assay, Northern blot, Western blot, gene transfection and MTT assay Results ATRA can inhibit the activator protein 1 (AP 1) activity in ATRA sensitive cell lines, but not in ATRA resistant cell line, and the anti AP 1 activity of ATRA is mediated by its receptor, retinoic acid receptor α (RARα) ATRA can also inhibit the expression of cJun and cFos One of the mechanisms for ATRA to inhibit the growth of gastric cancer cells may be through its inhibitory effect on the AP 1 activity and its influence on up regulation of RARα expression The inhibition of cJun and cFos expressions by ATRA may also contribute to the anti AP 1 activity Conclusions ATRA inhibits the growth of gastric cancer cells through the regulation of AP 1 activity This action is mediated by RARα展开更多
文摘AIM: To explore the effect of Astraga/us mongholicus polysaccharide (APS) on gene expression and mitogenactivated protein kinase (MAPK) transcriptional activity in intestinal epithelial cells (IEC). METHODS: IEC were divided into control group, lipopolysaccharide (LPS) group, LPS+ 50 μg/mL APS group, LPS+ 100 μg/mL APS group, LPS+ 200 μg/mL APS group, and LPS+ 500 μg/mL APS group. Levels of mRNAs in LPS-induced inflammatory factors, tumor necrosis factor (TNF)-α and interleukin (IL)-8, were measured by reverse transcription-polymerase chain reaction. MAPK protein level was measured by Western blotting. RESULTS: The levels of TNF-α and IL-8 mRNAs were significantly higher in IEC with LPS-induced damage than in control cells. APS significantly abrogated the LPS-induced expression of the TNF-α and IL-8 genes. APS did not block the activation of extracellular signal- regulated kinase or c Jun amino-terminal kinase, but inhibited the activation of p38, suggesting that APS inhibits LPS-induced production of TNF-α and IL-8 mRNAs, possibly by suppressing the p38 signaling pathway.CONCLUSION: APS-modulated bacterial productmediated p38 signaling represents an attractive strategy for prevention and treatment of intestinal inflammation.
文摘The incidence of obesity has dramatically increased in recent years.Consequently,obesity and associated disorders such as nonalcoholic fatty liver disease constitute a serious problem.Therefore,the contribution of adipose tissue to metabolic homeostasis has become a focus of interest.In this review,we discuss the latest discoveries that support the role of lipids in nonalcoholic fatty liver disease.We describe the common mechanisms(cJun aminoterminal kinases,endoplasmic reticulum stress,unfolded protein response,ceramide,lowgrade chronic inflammation)by which lipids and their derivatives impair insulin responsiveness and contribute to inflammatory liver and promote plaque instability in the arterial wall.Presenting the molecular mechanism of lipid activation of proinflammatory pathways,we attempt to find a link between nonalcoholic fatty liver disease,metabolic syndrome and cardiovascular diseases.Describing the common mechanisms by which lipid derivatives,through modulation of macrophage function,promote plaque instability in the arterial wall,impair insulin responsiveness and contribute to inflammatory liver and discussing the molecular mechanism of lipid activation of proinflammatory pathways,the key roles played by the proliferatoractivated receptor and liver X receptorα,nuclear receptorslipid sensors that link lipid metabolism and inflammation,should be emphasized.Further studies are warranted of antiinflammatory drugs such as aspirin,antiinterleukin6 receptors,immunemodulators(calcineurin inhibitors),substances enhancing the expression of heat shock proteins(which protect cells from endoplasmic reticulum stressinduced apoptosis),and anticJun aminoterminal kinases in welldesigned trials to try to minimize the high impact of these illnesses,and the different expressions of the diseases,on the whole population.
基金ThisstudywassupportedbytheNationalNaturalScienceFoundationofChina (No 39880 0 1 5 )andtheNationalOutstandingYouthScienceFoun
文摘To determine the mechanism of all trans retinoic acid (ATRA) on growth inhibition in human gastric cancer cells Methods Gastric cancer cell lines: MGC80 3, BGC 823, SGC 7901 and MKN 45 CAT assay, Northern blot, Western blot, gene transfection and MTT assay Results ATRA can inhibit the activator protein 1 (AP 1) activity in ATRA sensitive cell lines, but not in ATRA resistant cell line, and the anti AP 1 activity of ATRA is mediated by its receptor, retinoic acid receptor α (RARα) ATRA can also inhibit the expression of cJun and cFos One of the mechanisms for ATRA to inhibit the growth of gastric cancer cells may be through its inhibitory effect on the AP 1 activity and its influence on up regulation of RARα expression The inhibition of cJun and cFos expressions by ATRA may also contribute to the anti AP 1 activity Conclusions ATRA inhibits the growth of gastric cancer cells through the regulation of AP 1 activity This action is mediated by RARα