Inhibitory effect of heparin-derived oligosaccharides on secretion of interleukin-4 and interleukin-5 from human peripheral blood T lymphocytes

AIM: To investigate the inhibitory effect of heparin-derived oligosaccharides (Oligs) on secretion of interleukin-4 (IL-4) and interleukin-5 (IL-5) from human peripheral blood T lymphocytes (PBTLs).METHODS: Oligs were prepared by three different heparin depolymerization methods and separated by gel filtration chromatography. PBTLs from ten adult patients with allergic eosinophilic gastroenteritis were treated with phytahematoagglutinin (PHA) and Oligs. The supernatants from the cell culture of PBTLs were harvested and subjected to the determination of IL-4 and IL-5 contents by ELISA method.RESULTS: At the concentration of 5μg/mL, Oligs with different Mr had different effects on the secretion of IL-4 and IL-5. The tetrasaccharide with Mr of 1 142, produced by depolymerizing heparin with hydrogen peroxide, had the strongest inhibitory effect on the secretion of IL-4. It decreased the IL-4 content from 375.6±39.2 ng/L (PHA group) to 12.5±5.7 ng/L (P<0.01). The hexasaccharide with Mr of I 806, produced by depolymerizing heparin with βelimination method, had the strongest inhibitory effect on the secretion of IL-5. It decreased the IL-5 content from 289.2±33.4 ng/L (PHA group) to 22.0±5.2 ng/L (P<0.01).CONCLUSION: The inhibitory activity of Oligs on the secretion of IL-4 and IL-5 from human PBTLs closely depends on their molecular structure, and there may be an essential structure to act as an inhibitor. The most effective inhibitors of IL-4 and IL-5 secretion are tetrasaccharides and hexasaccharides, respectively.

Pterocarine, a New Diarylheptanoid from Pterocarya tonkinesis, its Cell Cycle Inhibition at G_0/G_1 Phase and Induction of Apoptosis in HCT-15 and K562 Cells

Pterocarine (1), a new diarylheptanoidal compound, was isolated from Pterocaryatonkinesis (Franch.) Dode. together with a known diarylheptanoid, myricatomentogenin (2), througha bioassay-guided fractionation procedure. The structure of 1 was elucidated as (+)-3', 4''-epoxy-1-(4'-hydroxyphenyl)-7-(3''-hydroxyphenyl)-heptane-3-one by the spectroscopic methods.Pterocarine (1) inhibited the proliferation of tsFT210, HCT-15 and K562 cells with the inhibitionrates of 20.2±2.4, 23.8±2.4 and 50.5±1.2% at 100 μg/mL, respectively. Flow cytometric analysisindicated that 1 could inhibit the cell cycle of tsFT210, HCT-15 and K562 cells at the G0/G1 phaseand could also induce apoptosis in HCT-15 (19%) and K562 (11%) cells.

Synthesis of Indomethacin Conjugates with D-Glucosamine

Two series of indomethacin conjugates with D-glucosamine were prepared with theobjectives of reducing ulcerogenic potency, increasing the bioavailability of indomethacin andexerting the coordinative effects on osteoarthritis. The structures of the conjugates were identifiedby H NMR and C NMR. The ester conjugates inhibited edema as potent as indomethacin. 1 13

Effects of dermatan sulfate derivatives on platelet surface P-selectin expression and protein C activity in blood of inflammatory bowel disease patients

AIM: To investigate the effect of derrnatan sulfate (DS) derivatives on platelet surface P-selectin expression and blood activated protein C (APC) activity in patients with inflammatory bowel disease (IBD), and to clarity the antiinflammatory mechanism of DS derivatives.METHODS: Derrnatan sulfate (DS) was sulfated with chlorosulfonic acid to prepare polysulfated derrnatan sulfate (PSDS). The major disaccharides of DS and PSDS were determined by 1H nuclear magnetic resonance spectroscopy (^1H-NMR) and ^13NMR. Both DS and PSDS were depolymerized with hydrogen peroxide. The fragments were separated by gel filtration chromatography. The effects of DS derivatives on P-selectin expression were assayed by ELISA method,and blood APC activity was assayed by the synthetic chrornogenic substrate method.RESULTS: The major disaccharides of DS and PSDS were IdoA-1→3-GalNAc-4-SO3 and IdoA-2SO3-1→3-GalNAc4, 6diSO3, respectively. Compared with the adenosine diphosphate stimulated group and IBD control group, DS and its derivatives all had significant inhibitory effects on P-selectin expression (P<0.01), but there was no difference between DS-derived oligosaccharides (DSOSs) and PSDS-derived oligosaccharides (PSDSOSs). The experiments on APC activity showed that DS and its derivatives all enhanced APC activity. The most active DSOS was the one with a relative molecular weight (Mr) of 4 825, which enhanced the APC activity from106.5±11.5% to 181.8±22.3% (P<0.01). With the decreaseof Mr, the activity of DSOSs decreased gradually. The effect of PSDS on APC activity enhancement was more significant than that of DS, and the APC activity was raised to 205.2±22.1% (P<0.01). All the PSDSOSs were more active than DSOSs on the basis of comparable Mr. With the decrease of Mr, the activity of PSDSOSs increased gradually, and the most active PSDSOS was PSDSOS3 with Mr of 2 749, which enhanced the APC activity to 331.2:1:27.8% (P<0.01), then the activity of PSDSOSs decreased gradually.CONCLUSION: DS and its derivatives can significantly inhibit P-selectin expression on platelet surface, but the effect has no correlation with DS molecular mass and sulfation.The effect of DS or its derivatives on APC activity at molecular level involves complex mechanisms that depend on the molecular mass, the degree of sulfation, and the heterogeneous composition of DS. On the same molecular size, the higher the degree of DS sulfation, the more significant the effect on enhancing APC activity.

Components of Stem Barks of Winchia calophylla A. DC. and Their Bronchodilator Activities

Abstract: The Dai medicinal plant Winchia calophylla A. DC. (Apocynaceae) has efficacy as an anti-cough and anti-asthmatic medication. In order to investigate its relative bioactive components, we studied the chemical constituents of this plant. Using repeated column chromatography, 28 compounds, including loganin, six phenolic compounds, 17 indole alkaloids, three pyridine alkaloids, and a quinoline alkaloid, were isolated from the stem barks of W. calophylla. Loganin, paeonol, N (4)-methyl akuammicine, and cantleyine exhibited a moderate relaxation effect on isolated smooth muscles of guinea-pig tracheal spirals and lung strips and may be the bioactive components responsible for the bronchodilation produced by W. calophylla.