Lipopolysaccharides(LPS) contamination in herbal crude polysaccharides is inevitable. The present study was performed to explore the effect of polymyxin B on abolishing the influence of LPS contamination in mononuclea...Lipopolysaccharides(LPS) contamination in herbal crude polysaccharides is inevitable. The present study was performed to explore the effect of polymyxin B on abolishing the influence of LPS contamination in mononuclear cells. LPS was pretreated with polymyxin B sulfate(PB) at different concentrations for 1, 5 or 24 h, and then used to stimulate RAW264.7 and mouse peritoneal macrophages(MPMs). The nitric oxide(NO) and tumor necrosis factor-α(TNF-α) in cell culture supernatant, as the indications of cell response, were assayed. Bupleurum chinensis polysaccharides(BCPs) with trace amount contamination of LPS was treated with PB. 30 μg·mL^(–1) of PB, treating LPS(10 and 1000 ng·mL^(–1) in stimulating RAW264.7 and MPMs respectively) at 37 ℃ for 24 h, successfully abolished the stimulating effect of LPS on the cells. When the cells were stimulated with LPS, BCPs further promoted NO production. However, pretreated with PB, BCPs showed a suppression of NO production in MPMs and no change in RAW264.7. In the in vitro experiments, LPS contamination in polysaccharide might bring a great interference in assessing the activity of drug. Pretreatment with PB(30 μg·mL^(–1)) at 37 °C for 24 h was sufficient to abolish the effects of LPS contamination(10 and 1 000 ng·mL^(–1)).展开更多
基金supported by the National Natural Science Foundation of China(Nos.81330089,30925042,and 81274165)the State Key Program for New Drugs from the Ministry of Science and Technology,China(No.2012ZX09301001-003)the Science and Technology Commission of Shanghai Municipality(Nos.10XD1405900 and 12JC1400800)
文摘Lipopolysaccharides(LPS) contamination in herbal crude polysaccharides is inevitable. The present study was performed to explore the effect of polymyxin B on abolishing the influence of LPS contamination in mononuclear cells. LPS was pretreated with polymyxin B sulfate(PB) at different concentrations for 1, 5 or 24 h, and then used to stimulate RAW264.7 and mouse peritoneal macrophages(MPMs). The nitric oxide(NO) and tumor necrosis factor-α(TNF-α) in cell culture supernatant, as the indications of cell response, were assayed. Bupleurum chinensis polysaccharides(BCPs) with trace amount contamination of LPS was treated with PB. 30 μg·mL^(–1) of PB, treating LPS(10 and 1000 ng·mL^(–1) in stimulating RAW264.7 and MPMs respectively) at 37 ℃ for 24 h, successfully abolished the stimulating effect of LPS on the cells. When the cells were stimulated with LPS, BCPs further promoted NO production. However, pretreated with PB, BCPs showed a suppression of NO production in MPMs and no change in RAW264.7. In the in vitro experiments, LPS contamination in polysaccharide might bring a great interference in assessing the activity of drug. Pretreatment with PB(30 μg·mL^(–1)) at 37 °C for 24 h was sufficient to abolish the effects of LPS contamination(10 and 1 000 ng·mL^(–1)).
