Effects of Angelica Polysaccharide on telomere length in mice with benzene-induced aplastic anemia

Objective:To investigate the changes in telomere length and the level of burst-forming units-erythrocyte(BFU-Es)and colony-forming unit-erythrocytes(CFU-Es)in mice with benzene-induced aplastic anemia(AA),and follow-up the therapeutic effects of Angelica Polysaccharide(AP).Methods:Male BALB/c mice(n=120)were randomly divided into three groups(1,2,3):normal control(n=24),AA control(n=48),and treated AA(n=48),respectively.Mice in Group 2 received benzene inhalation for 2.5 months and 1 ml distilled water p.o.per day for 2 weeks after the establishment of AA models.Similar procedure was applied to the mice in Group 3 and AP was given for 2 weeks after the establishment of AA models.Real-time polymerase chain reaction was used to survey relative telomere length measurement of the bone marrow cells.A BFU-Es and CFU-Es survey was done to follow-up the therapeutic effects of AP.Results:Compared with normal control,significant reductions of RBC,WBC,and platelet counts were found in peripheral blood of AA mice.After treatment with AP,counts of BFU-Es and CFU-Es were restored up to 66.8%and 77.25%,respectively,and length of telomere was restored up to 76.34%,of the normal levels.The telomere length in treated AA group was higher than the control AA group.Conclusion:The AP can protect the telomere length and differentiation of hemopoietic stem/progenitor cells,accelerate the recovery of BFU-Es and CFU-Es of AA mice,and then improve the bone marrow failure.

Preparation and Identification of Angelica sinensis Polysaccharide-iron Complex

Angelica sinensis polysaccharide（ASP） was extracted from Angelica sinensis by boiling water. An Angelica sinensis polysaccharide-iron complex（APC） was prepared under the alkaline condition by adding a ferric chloride solution to the ASP solution. Then some identifiable properties of the complex were studied. The content of iron（ Ⅲ ） in the complex was determined with iodometry. The thermal property, the microscopic structure, the spectral characteristics, and N, C, H contents of the complex were examined by a variety of techniques including DSC, TEM, IR, NMR, and elemental analysis. The content of iron（ Ⅲ ） in the complex ranges from 10% to 40%. The DSC result shows that the melting point of the complex is about 450 ℃. The TEM result shows that the complex has an iron（ Ⅲ ） core（β-FeOOH core） linked by hydroxy and oxy bridges, with the polysaccharide chains attached to the surface of the core. The IR and NMR results also show that there is a β-FeOOH core in the complex. The elemental analysis shows that the contents of N, C, H in the complex are, respectively, lower than those of N, C, H in ASP. All our studies indicate that the APC consists of a β-FeOOH core surrounded by ASP.

Angelica sinensis polysaccharides ameliorate 5-flourouracil-induced bone marrow stromal cell proliferation inhibition via regulating Wnt/β-catenin signaling

Chemotherapy may cause cellular oxidative stress to bone marrow.Oxidative damage of bone marrow hematopoietic microenvironment is closely related to chronic myelosuppression after chemotherapeutic treatment.Angelica sinensis polysaccharides(ASP)are major effective ingredients of traditional Chinese medicine Angelica with multi-target anti-oxidative stress features.In the current study,we investigated the protective roles and mechanisms of ASP on chemotherapy-induced bone marrow stromal cell(BMSC)damage.The human bone marrow stromal cell line HS-5 cells were divided into control group,5-FU group,5-FU+ASP group,and 5-FU+LiCl group to investigate the mechanism of ASP to alleviate 5-FU-induced BMSC proliferation inhibition.The results showed that 5-FU inhibits the growth of HS-5 cells in a time and dose-dependent manner;however,ASP partially counteracted the 5-FU-induced decrease in cell viability,whereas Wnt signaling inhibitor Dkk1 antagonized the effect of ASP on HS-5 cells.ASP reversed the decrease in total cytoplasmicβ-catenin,p-GSK-3β,and CyclinD1 following 5-FU treatment and modulated nuclear expression ofβ-catenin,Lef-1,and C-myc proteins.Furthermore,ASP also enhanced the antioxidant capacity of cells and reduced 5-FU-induced oxidative stress,attenuated FoxO1 expression,thus weakened its downstream apoptosis-related proteins and G0/G1 checkpoint-associated p27^(Kip1) expression to alleviate 5-FU-induced apoptosis and to promote cell cycle progression.All the results above suggest that the protective role of ASP in 5-FU-treated BMSCs proliferation for the chemotherapy may be related to its activating Wnt/β-catenin signaling and keeping homeostasis betweenβ-catenin and FoxO1 under oxidative stress.The study provides a potential therapeutic strategy for alleviating chemotherapeutic damage on BMSCs.

Mitochondrial membrane stabilization by Angelica sinensis polysaccharide in murine aplastic anemia

In order to investigate the mechanism of mitochondrial membrane stabilization by Angelica sinensis polysaccharide (ASP) in murine aplastic anemia (AA).ICR mice were randomly divided into control, AA and ASP-treated groups. The AA group mice were treated with 60Coγand intraperitoneal injections of cyclophosphamide and chloramphenicol. The control animals were treated with lead shielding irradiation and saline injection. The treated AA mice were fed with ASP for 2 wk. Mitochondrial ultrastructure of the bone marrow was observed by transmission electron microscopy, and the transmembrane potential of bone marrow-nucleated cells (BMNC)was examined by fluorescence spectrophotometry. The Cox and MDH contents of the medium were also studied in the three groups.The mitochondrial number and transmembrane potential of BMNC in the bone marrow decreased in the AA group as compared to the control group, but improved in the ASP-treated group as compared to the AA group. Complete mitochondrial cleavage in the ASP-treated group was significantly delayed (P<0.05) as compared to the AA group. We conclude that ASP might improve mitochondrial membrane stabilization, and suppress the downregulation of transmembrane potential and apoptosis of BMNC in AA.

Comparison of Two Kinds of Magnetic Nanoparticles In Vivo and In Vitro

This study compared a new type of polysaccharide-coated magnetic nanoparticles （in which the polysaccharide is derived from Angelica sinensis） with the dextran magnetic nanoparticles in terms of preparation, biocompatibility and tissue distribution in vivo and in vitro in order to examine the potential application of Angelica polysaccharide as a novel carrier in magnetic drug targeting （MDT）. Magnetic nanoparticles were prepared by chemical co-precipitation. Their physical and chemical properties were determined by using the transmission electron microscope （TEM）, laser particle size analyzer （DLS） and vibrating sample magnetometer （VSM）, and their purity and structure by using X-ray diffractometer （XRD） and Fourier transform infrared spectroscopy （FTIR）. The atomic absorption spectrometric method was performed for quantification of the iron content in different tissues. Histological sections were stained by Prussian blue staining to observe the disposition of magnetic nanoparticles in the liver and kidney. The results showed that both kinds of magnetic nanoparticles possessed small particle size, good dispersion and good magnetic properties. XRD showed the main component of the two magnetic nanoparticles was Fe3O4 crystals, and FTIR proved Fe3O4 was successfully coated by each polysaccharide, respectively. In vivo, Fe3O4-dextran accumulated in the liver, spleen and lung and Fe3O4-Angelica polysaccharide only in the spleen and lung. It was concluded that Angelica polysaccharide may be applied as a novel carrier in the preparation of magnetic nanoparticles.

Study on Intervenient Effect of Angelica Sinensis Polysaccharide on Immunological Liver Injury and Its Mechanism in Mice

Objective: To study the changes of expressions of nitric oxide synthase (NOS) of the constitutive type (cNOS) and inducible type (iNOS), the apoptosis related genes bax and bcl 2, as well as the tumor necrosis factor (TNF α) in immunological liver injury (ILI) and to explore the preventive effects of Angelica sinensis polysaccharide (ASP) on ILI and its mechanism in mice.Methods: ILI model mice induced by intraperitoneal injection of lipo polysaccharide (LPS) and BCG vaccine were treated with ASP of different doses (30mg/kg, 60mg/kg) by gastrogavage every day for 7 days. The serum alanine transaminase (ALT) and glutathione S transferase (GST) activities and NO content in the liver were detected; the expressions of cNOS, iNOS, bcl 2, bax were assessed with immuno histochemical method, and the TNF α mRNA expression in the liver was observed by reverse transcriptase polymerase chain reaction (RT PCR).Results: Compared with the normal mice , the NO production and ALT, GST levels were raised significantly in the model mice, the TNF α mRNA expression was also raised significantly. But no obvious changes of cNOS was found. Small dose ASP (30mg/kg) could reduce NO production and ALT, GST levels in model mice by 19.5%, 23.7% and 40.0% respectively, decrease the expression of iNOS and bax by 48.3%, and 26.4%, and increase the expression of cNOS, bcl 2 by 66.9% and 337.3%, respectively, but it could not reduce the TNF α mRNA expression in the liver. Large dose of ASP (60mg/kg) was not more effective than that of small dose.Conclusion: Changes of NO production and TNF α mRNA may play an important role in ILI. The mechanism of ASP in intervening ILI may be through modulation on cNOS, iNOS, bax, bcl 2 expression to block the damage of BCG vaccine and LPS on hepatocytes.

Effect of Angelica Sinensis Polysaccharide-lron Complex on Iron Deficiency Anemia in Rats

Objective： To investigate the therapeutic effects of Angelica sinensis polysaccharideiron complex （APIC） on rats with iron deficiency anemia （IDA）. Methods： The IDA rat model was established by adopting low-iron forage with a small amount of regular bloodletting. The rats were randomly divided into a model group, three AIPC groups （high, middle, and low dosage）, an Angelica sinensis polysaccharide （ASP） group, a mixture group （ASP＋FeCl3） and a positive control group （Niferex）. Changes in hemoglobin （Hb）, red blood cell count （RBC）, hematocrit （HCT） and iron content of whole blood were observed. Results： There was a significant difference before and after administration in all treated groups and all indices were restored to near-normal levels in the APIC groups and the positive control group. There was a significant difference among the changes of the indices in all the APIC groups and those of the model group but not between those of the APIC groups and the positive control group. However, the recovery of the indices in the APIC groups was superior to that in the positive control group. Conclusion： APIC not only has a superior therapeutic effect on IDA, but also has the effect of the ASP on supplementing blood and activating blood circulation. Hence, it may be used as a new iron-supplementing agent with a double therapeutic efficacy on blood supplementation for the treatment of IDA.

Fe_(3)O_(4)@Angelica sinensis polysaccharide nanoparticles as an ultralow-toxicity contrast agent for magnetic resonance imaging

Although iron oxide(Fe_(3)O_(4)) nanoparticles have broad application prospects as magnetic resonance imaging(MRI) contrast agent, their biocompatibility and biotoxicity still need to be improved. In this study, we prepared Fe_(3)O_(4)@Angelica sinensis polysaccharide nanoparticles(Fe_(3)O_(4)@ASP NPs) with a 9 nm Fe_(3)O_(4) core and ASP as the coating material. The Fe_(3)O_(4)@ASP NPs are superparamagnetic, can be taken up by liver and spleen macrophages in the circulatory system in vivo, and are a good-biocompatibility and low-toxicity transverse relaxation time(T_(2)) and T_(2)-star(T_(2)^(*)) magnetic resonance imaging(MRI) contrast agent for the liver. The cytotoxicity assessment using HeLa cells and the pathological tests in mice validate that Fe_(3)O_(4)@ASP NPs have low toxicity and good biocompatibility in vivo, which can be attributed to the ASP as a natural polysaccharide with good biocompatibility and its function of protecting the liver. Fe_(3)O_(4)@ASP NPs are a potential new MRI contrast agent with high signal intensity in vivo.