Cui Liu

Immunoenhancement effect of rehmannia glutinosa polysaccharide on lymphocyte proliferation and dendritic cell.

The aim of this study is to investigate immunomodulatory effect of rehmannia glutinosa polysaccharide (RGP) on murine splenic lymphocyte and bone marrow derived dendritic cells (DCs). Splenic lymphocytes obtained from mice were co-cultured with RGP for 48 h and then harvested for analyzing with MTT method. The cytokine production of T lymphocytes was measured by ELISA. Effects of RGP treatment on DCs were investigated and assessed by MTT method. The results showed RGP significantly stimulated lymphocyte proliferation and the growth rate of T cell was more significant. The IL-2 and IFN-γ production of T lymphocyte were significantly upregulated after being stimulated with RGP. DCs stimulating on proliferation of T cells and the ability of antigen presenting of DCs have been enhanced under the stimulation of RGP. In conclusion, these findings provided valuable information that RGP possessed strong immunoenhancement activity, which provided the theoretical basis for the further experiment.

Optimization of selenylation conditions for Chinese angelica polysaccharide based on immune-enhancing activity

Chinese angelica polysaccharide (CAP) was extracted by water decoction and ethanol precipitation, purified through eliminating protein by Sevage method and column chromatography of Sephadex G-200, then selenizingly modified by nitric acid-sodium selenite method according to L(9)(3(4)) orthogonal design of three-factors, the usage amount of sodium selenite, reaction temperature and reaction time, at three level to obtain nine selenizing CAPs, sCAP(1)-sCAP(9). Their effects on chicken peripheral lymphocytes proliferation in vitro were compared by MTT assay taking the non-modified CAP as control. The results showed that selenylation modification could significantly enhance the immune-enhancing activity of CAP, sCAP(2) presented best effect and the optimal modification conditions were 200mg of sodium selenite for 500 mg of CAP, the reaction temperature of 70 °C and the reaction time of 6 h.

Optimization of selenylation conditions for lycium barbarum polysaccharide based on antioxidant activity.

Lycium barbarum polysaccharide (LBP) was modified by HNO3-Na2SeO3 method according to L9(3(4)) orthogonal design to obtain nine selenizing LBPs (sLBPs), sLBP1-sLBP9. Their antioxidant activities in vitro were compared by free radical-scavenging test. sLBP6, sLBP8 and sLBP9 presented stronger activity. In vivo test, 14-day-old chickens were injected respectively with sLBP6, sLBP8 and sLBP9 taking LBP as control, and serum GSH-Px and SOD activities and MDA content were determined. The results showed that three sLBPs could significantly enhance GSH-Px and SOD activities and decrease MDA content. The actions of sLBPs were significantly stronger than that of unmodified LBP. These results indicated that selenylation modification could significantly enhance the antioxidant activities of LBP, sLBP6 possessed the best efficacy and could be exploited into an antioxidant. The optimal modification conditions were 400mg of sodium selenite for 500 mg of LBP, reaction temperature of 70 °C and reaction time of 6h.

The immunological activity of propolis flavonoids liposome on the immune response against ND vaccine.

Three hundred and fifty 14-day-old chickens were randomly assigned to 7 groups. At the same time of vaccination with Newcastle disease vaccine, the chickens in experimental groups were injected with propolis flavonoids liposome (PFL) at three doses, PF and blank liposome, respectively. The titer of serum antibody, concentrations of immunoglobulins G (IgG) and immunoglobulins M (IgM), activity of lymphocytes proliferation and concentrations of cytokines were measured. The results showed that three doses of PFL could significantly enhance antibody titer, concentrations of IgG, IgM, and promote lymphocyte proliferation, interferon-γ and interleukin-2 secretion, and its high and medium doses possessed the best efficacy. In general evaluation, the efficacy of PFL was the best, with certain of dose- and time-effect relationships. These findings indicated that the immunological activity of PF could be enhanced with liposome encapsulation.

Astragalus polysaccharide and sulfated epimedium polysaccharide synergistically resist the immunosuppression.

The immunoenhancement of compound polysaccharides, APS-sEPS composed with astragalus polysaccharide (APS) and sulfated epimedium polysaccharide (sEPS), was observed in immunosuppressed model chicken induced by cyclophosphamide (Cy). 11-day-old chickens were injected with Cy once a day for three successive days except vaccine control group. At day-14-old, all chickens were vaccinated with ND vaccine, and in experimental groups simultaneously administrated with APS-sEPS at three dosages, APS and sEPS once a day for three successive days. On days 7, 14, 21 and 28 after the administration, the peripheral T-lymphocyte proliferation, serum antibody titers, IFN-γ, IL-2, IgG and IgM were determined. The results displayed that APS-sEPS could overcome Cy-induced immunosuppression, significantly promote T-lymphocyte proliferation and raised serum antibody titers, IFN-γ, IL-2, IgG and IgM levels, its high and medium doses were superior to single APS or sEPS. This demonstrated that APS and sEPS could synergistically resist the immunosuppression and APS-sEPS was an effective immunopotentiator.

Effect of selenylation modification on immune-enhancing activity of Atractylodes macrocephala polysaccharide

The Atractylodes macrocephala polysaccharide (AMP) was extracted purified and modified in selenylation by Nitric acid-sodium selenite method to get nine selenizing AMPs (sAMPs), sAMP(1)-sAMP(9). In vitro test their effects on chicken peripheral lymphocyte proliferation were determined by MTT assay. The results showed that nine sAMPs and AMP at five concentrations could significantly promote lymphocyte proliferation, the actions in six sAMPs were significantly stronger than that in AMP, and in sAMP(9) was the strongest. In vivo test, 14-day-old chickens vaccinated with ND vaccine were injected respectively with sAMP(9) and AMP, the peripheral lymphocytes proliferation, serum antibody titer, IFN-γ, IL-2 and IL-6 contents were determined. The results displayed that the sAMP could significantly promote lymphocyte proliferation and elevate the antibody titers and content of IFN-γ, IL-2 and IL-6 in comparison with unmodified AMP. These results indicate that selenylation modification can significantly enhance the immune-enhancing activity of AMP.

Optimization on conditions of Lycium barbarum polysaccharides liposome by RSM and its effects on the peritoneal macrophages function

The purpose of this study was to optimize the preparation conditions of Lycium barbarum polysaccharides liposome (LBPL) by response surface methodology (RSM) and to investigate the effect of LBPL activating function of peritoneal macrophages. LBPL was prepared using the reverse-phase evaporation method. The optimal preparation conditions of LBPL by RSM were as follows: the ratio of lipid to drug (w/w) of 25:1, the ultrasound time of 14 min and the ratio of soybean phospholipids to cholesterol (w/w) of 2.4:1. Under these conditions, the experimental encapsulation efficiency of LBPL was 86.37±0.63%, which was close to the predicted value. These indicated that LBPL with high entrapping efficiency and small particle size could be prepared by the reverse-phase evaporation method, which is applied easily. Furthermore, macrophages are the key players in the innate immune system. LBPL could effectively enhance peritoneal macrophages phagocytosis and resulted in inducing NO (nitric oxide) production in mouse peritoneal macrophages.

The optimization of sulfation modification conditions for ophiopogonpolysaccharide based on antiviral activity.

Ophiopogonpolysaccharide (OPS) was extracted by water decoction and ethanol precipitation, purified through eliminating protein by trichloroacetic acid method and column chromatography of DEAE-Cellulose-52, then sulfatedly modified by chlorosulfonic acid-pyridine method according to three-factors, ratio of chlorosulfonic acid to pyridine, reaction temperature and reaction time, and three level L₉(3⁴) orthogonal designed to obtain nine sulfated OPSs, sOPS₁-sOPS₉. Their effects on NDV to infect chick embryo fibroblast were compared by MTT assay taking the non-modified OPS as control. The results showed that sulfation modification could significantly enhance the antiviral activity of OPS, sOPS₃ presented best effect and the optimal modification conditions were the ratio of chlorosulfonic acid to pyridine of 1:4, the reaction temperature of 60 °C and the reaction time of 2 h.

Optimization of selenylation modification for garlic polysaccharide based on immune-enhancing activity.

Garlic polysaccharide (GPS) was modified in selenylation respectively by nitric acid-sodium selenite (NA-SS), glacial acetic acid-selenous acid (GA-SA), glacial acetic acid-sodium selenite (GA-SS) and selenium oxychloride (SOC) methods each under nine modification conditions of L9(3(4)) orthogonal design and each to obtain nine selenizing GPSs (sGPSs). Their structures were identified, yields and selenium contents were determined, selenium yields were calculated, and the immune-enhancing activities of four sGPSs with higher selenium yields were compared taking unmodified GPS as control. The results showed that among four methods the selenylation efficiency of NA-SS method were the highest, the activity of sGPS5 was the strongest and significantly stronger than that of unmodified GPS. This indicates that selenylation modification can significantly enhance the immune-enhancing activity of GPS, NA-SS method is the best method and the optimal conditions are 0.8:1 weight ratio of sodium selenite to GPS, reaction temperature of 70 °C and reaction time of 10h.

The comparison of antioxidative and hepatoprotective activities of Codonopsis pilosula polysaccharide (CP) and sulfated CP

Codonopsis pilosula polysaccharide (CP) was extracted, purified and modified by chlorosulfonic acid-pyridine method to obtain a sulfated CP (sCP). Their antioxidative activities in vitro were compared through the free radical-scavenging test. The results demonstrated that the scavenging capabilities of sCP were significantly stronger than those of CP. In vivo test, the mice hepatic injury model was prepared by BCG/LPS method, then administrated respectively with sCP and CP at three dosages, the biochemical indexes in serum, antioxidative indexes in liver homogenate and histopathological change in liver of the mice were compared. The results showed that in high (200mg/kg) and middle (150mg/kg) dosages of sCP groups, the contents of ALT, AST and TNF-α in serum and MDA in liver homogenate were significantly lower than those in the model group and numerically lower than those in the CP groups, the activities of SOD and GSH-Px in liver homogenate were significantly higher than those in the model group and numerically higher than those in the CP groups. In the model group there were obvious pathological changes in the liver, while in the sCP groups were near normal. These results indicate that sCP and CP possess antioxidative activity in vitro and in vivo, the activity of sCP is stronger than that of CP and sulfation modification can enhance the antioxidative and hepatoprotective activities of Codonopsis pilosula polysaccharide.