In this study, we evaluated the chemical property and antioxidant activity of fucoidans isolated from brown algae, Laminaria japonica(LJF), Lessonia nigrescens(LNF), Lessonia trabeculata(LTF), Ascophyllum mackaii(AMF)...In this study, we evaluated the chemical property and antioxidant activity of fucoidans isolated from brown algae, Laminaria japonica(LJF), Lessonia nigrescens(LNF), Lessonia trabeculata(LTF), Ascophyllum mackaii(AMF), and Ecklonia maxima(EMF). LJF was less in sulfate content(14.16%) and more in galactose and mannose content(1.08 and 0.68) than the documented early. EMF contained 20%–30% of sulfate and fucose, 0.97 in molar ratio which was lower than that of sulfate to other four fucoidans(1.21–1.41). AMF(162 kDa) and EMF(150 kDa) were the first two largest in molecular weight, which were followed by LJP(126 kDa), LNF(113 kDa) and LTF(105 kDa). The fucoidans isolated these algae showed a wide range of antioxidant activity in vitro. It was found that the reducing power of the isolated fucoidans was positively correlated with their sulfate content and molecular weight. In addition, LNF and LTF at low concentrations exhibited high superoxide and hydroxyl radical scavenging activity. This demonstrated that low molecular weight fucoidans may perform a high antioxidant activity.展开更多
This study was carried out explore the mechanism underlying the inhibition of platelet activation by kelp fucoidans in deep venous thrombosis(DVT)mouse.In the control and sham mice,the walls of deep vein were regular ...This study was carried out explore the mechanism underlying the inhibition of platelet activation by kelp fucoidans in deep venous thrombosis(DVT)mouse.In the control and sham mice,the walls of deep vein were regular and smooth with intact intima,myometrium and adventitia.The blood vessel was wrapped with the tissue and there was no thrombosis in the lumen.In the DVT model,the wall was uneven with thicken intima,myometrium and adventitia.After treated with fucoidans LF1 and LF2,the thrombus was dissolved and the blood vessel was recanalized.Compared with the control group,the ROS content,ET-1 and VWF content and the expression of PKC-βand NF-κB in the model were significantly higher(P<0.05);these levels were significantly reduced following treatments with LF2 and LF1.Compared with H_(2)O_(2)treated-HUVECs,combined LF1 and LF2 treatment resulted in significant decrease in the expression of PKC-β,NF-κB,VWF and TM protein(P<0.05).It is clear that LF1 and LF2 reduces DVT-induced ET-1,VWF and TM expressions and production of ROS,thus inhibiting the activation of PKC-β/NF-κB signal pathway and the activation of coagulation system and ultimately reducing the formation of venous thrombus.展开更多
In this study,fucoidans were extracted from the sea cucumber Thelenota ananas(Ta-FUCs)by enzymatic degradation.Four products with molecular weights of 1380.3,524.0,182.4,and 110.3 kDa were obtained,and the Ta-FUC show...In this study,fucoidans were extracted from the sea cucumber Thelenota ananas(Ta-FUCs)by enzymatic degradation.Four products with molecular weights of 1380.3,524.0,182.4,and 110.3 kDa were obtained,and the Ta-FUC showing optimal anti-adipogenic activities was determined.Results of MTT and Oil red O staining analyses showed that the Ta-FUCs inhibited the proliferation and differentiation of 3T3-L1 adipocytes.Futhermore,Ta-FUCs significantly downregulated the key transcriptional factors,such as SREBP-1c,PPARγ,and C/EBPαof adipocytes.The Ta-FUCs also activated Wnt/β-catenin pathway-related genes,such asβ-catenin,LRP5,and FrZ.The Ta-FUCs suppressed lipid accumulation in 3T3-L1 adipocytes possibly by decreasing the expression of genes ACC,FAS,ME,GPAT,DGAT,and PILN,which are important in the synthesis of fatty acids and triglycerides;and by increasing the expression of genes PPARα,CPT-1α,and ACOX,which are crucial in fatty acidβ-oxidation.The anti-adipogenic activities initially increased and then declined with decreasing molecular weight.Among the Ta-FUCs,the 182.4 kDa Ta-FUC exhibited optimal bioactivities.This study reports for the first time that Ta-FUCs can prevent obesity by regulating the differentiation and lipid accumulation of adipocytes.展开更多
Five fucoidan fractions from Laminaria japonica with different sulfate content and molecular weight were prepared by anion-exchange chromatography and mild acid hydrolysis. Their antioxidant effects on azo radicals 2-...Five fucoidan fractions from Laminaria japonica with different sulfate content and molecular weight were prepared by anion-exchange chromatography and mild acid hydrolysis. Their antioxidant effects on azo radicals 2-2＇-Azobis （2-amidinopropane） dihydrochloride （AAPH） induced oxidation of human low-density lipoprotein （LDL） were evaluated by monitoring cholesteryl ester hydroperoxides （CHL-OOH） formation kinetics through reverse-phase high performance liquid chromatography （RP-HPLC） analysis. Fucoidan F - C with a low molecular mass of 2 000 ～8 000 and a sulfate content of 24.3% had much stronger protective antioxidant effect than other four fucoidan fractions on the hydrophilic radical AAPH induced LDL oxidation. However, the highly sulfated fucoidan fraction L - B with a molecular mass of 20 000 was completely ineffective in protecting LDL from the AAPH induced oxidation. The results suggested that both molecular mass and sulfate content of fucoidan played very important roles in their effects on the AAPH induced LDL oxidation.展开更多
Objective:To investigate the therapeutic adjuvant potential of fucoidan in cervical cancer and to evaluate its efficacy in combination with immunotherapy.Methods:Fucoidan extracted from Fucus vesiculosus was dissolved...Objective:To investigate the therapeutic adjuvant potential of fucoidan in cervical cancer and to evaluate its efficacy in combination with immunotherapy.Methods:Fucoidan extracted from Fucus vesiculosus was dissolved in phosphate buffered saline and used to treat TC-1 cervical cancer cells in vitro as well as tumor-bearing C57BL/6 mice in vivo.Mice were divided into four groups:the vehicle control group,the mRNA therapy-alone group,the fucoidan-only group,and the combination group.MAPK signaling proteins(p-ERK,T-ERK,p-p38)were analyzed by Western blotting assays.T cell surface markers and intracellular cytokines in splenocytes were assessed by flow cytometry,and plasma cytokine levels were measured by ELISA.Results:Fucoidan decreased the p-ERK/T-ERK ratio and p-p38.Fucoidan combined with mRNA therapy did not significantly affect CD4^(+)T-cell activation but reduced CD8^(+)T-cell activation compared with mRNA therapy alone.MCP-1 and IFN-γwere significantly reduced in the combination therapy group compared with mRNA therapy alone,while IL-6,TNF-α,perforin,and granzyme B did not show significant changes between the two groups.Conclusions:These findings suggest that fucoidan could inhibit excessive T cell activation and cytokine production by suppressing MAPK p-p38 protein expression.展开更多
Mastitis often occurs during women's lactation period,causing great psychological and physical pain to women.Fucoidan,a sulfated polysaccharide obtained from brown algae,has much broader biological properties.Howe...Mastitis often occurs during women's lactation period,causing great psychological and physical pain to women.Fucoidan,a sulfated polysaccharide obtained from brown algae,has much broader biological properties.However,the roles of fucoidan in lipopolysaccharides(LPS)-induced mastitis are still undiscovered.The present study was aimed to evaluate the influences of fucoidan on LPS-induced mouse mastitis and investigate its possible mechanisms.The expression profiles of fucoidan acting on mastitis were analyzed by network pharmacology.Additionally,mechanism experiments verified the mechanism of fucoidan on mastitis.The results of in vivo study displayed that the treatment of fucoidan to LPS-stimulated mouse mastitis decreased the inflammatory damage,proinflammatory cytokines level and repaired the completeness of bloodmilk barrier.In the study of mouse mammary epithelial cells,fucoidan suppressed the secretion of reactive oxygen species(ROS)and enhanced the activity of antioxidant enzymes.Molecular experiments suggested that fucoidan promoted nuclear factor erythroid 2-related factor 2(Nrf2)nuclear import and autophagy via activating the adenosine 5'-monophosphate-activated protein kinase(AMPK)signaling pathway.The above results indicated that in mastitis,fucoidan promoted Nrf2 nuclear import and autophagy via activating the AMPK signaling pathway,thereby suppressing oxidative stress and inflammatory injury to the mammary glands and protecting the blood-milk barrier.展开更多
目的:探讨ERK信号通路在内质网应激时由A类清道夫受体(SR-A)介导的细胞凋亡中的作用。方法:ERK磷酸化和葡萄糖相关蛋白78(GRP78)的表达用Western blot方法检测,细胞活性用四甲基噻唑蓝(MTT)实验检测,同时应用Annexin V FITC/PI双染流式...目的:探讨ERK信号通路在内质网应激时由A类清道夫受体(SR-A)介导的细胞凋亡中的作用。方法:ERK磷酸化和葡萄糖相关蛋白78(GRP78)的表达用Western blot方法检测,细胞活性用四甲基噻唑蓝(MTT)实验检测,同时应用Annexin V FITC/PI双染流式细胞术检测细胞凋亡率。结果:Western blot结果显示,fucoidan可以持续激活ERK,并且在1～4h达到最强,这种作用在SR-A基因敲除小鼠的腹腔巨噬细胞中明显减弱。用PD98059阻断ERK信号途径后,内质网应激时fucoidan诱导RAW264.7细胞凋亡率明显降低。结论:在发生内质网应激时,fucoidan与SR-A结合后激活ERK信号通路,可能是促进巨噬细胞凋亡的机制之一。展开更多
AIM:To evaluate the protective effects of fucoidan on oxidative stress-induced barrier disruption in human intestinal epithelial cells.METHODS:In Caco-2 cell monolayer models,the disruption of barrier function by oxid...AIM:To evaluate the protective effects of fucoidan on oxidative stress-induced barrier disruption in human intestinal epithelial cells.METHODS:In Caco-2 cell monolayer models,the disruption of barrier function by oxidative stress is mediated by H2O2.The integrity of polarized Caco-2 cell monolayers was determined by measuring the transepithelial resistance(TER)and permeability was estimated by measuring the paracellular transport of FITC-labeled4-kDa dextran(FD4).The protective effects of fucoidan on epithelial barrier functions on polarized Caco-2 cell monolayers were evaluated by TER and FD4 flux.The expression of tight junction(TJ)proteins was assessed using reverse-transcription polymerase chain reaction(RT-PCR)and immunofluorescence staining.RESULTS:Without H2O2treatment,fucoidan significantly increased the TER compared to control(P<0.05),indicating a direct enhancement of intestinal epithelial barrier function.Next,H2O2disrupted the epithelial barrier function in a time-dependent manner.Fucoidan prevented the H2O2-induced destruction in a dosedependent manner.Fucoidan significantly decreased H2O2-induced FD4 flux(P<0.01),indicating the prevention of disruption in paracellular permeability.RTPCR showed that Caco-2 cells endogenously expressed claudin-1 and-2,and occludin and that H2O2reduced the mRNA expression of these TJ proteins.Treatment with fucoidan attenuated the reduction in the expressions of claudin-1 and claudin-2 but not occludin.Immunofluorescence staining revealed that the expression of claudin-1 was intact and high on the cell surface.H2O2disrupted the integrity of claudin-1.Treatment with fucoidan dramatically attenuated the expression of claudin-1.CONCLUSION:Fucoidan enhanced intestinal epithelial barrier function by upregulating the expression of claudin-1.Thus,fucoidan may be an appropriate therapy for the treatment of inflammatory bowel diseases.展开更多
The antiviral activity in vitro and in vivo and the effect of the immune system of two fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica(LMW fucoidans) were investigate...The antiviral activity in vitro and in vivo and the effect of the immune system of two fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica(LMW fucoidans) were investigated in order to examine the possible mechanism. In vitro, I-type influenza virus, adenovirus and Parainfluenza virus I were used to infect Hep-2, Hela and MDCK cells, respectively. And 50% tissue culture infective dose was calculated to detect the antiviral activity of two LMW fucoidans. The results indicated that compared with the control group, 2 kinds of LMW fucoidans had remarkable antiviral activity in vitro in middle and high doses, while at low doses, the antiviral activity of 2 kinds of LMW fucoidans was not statistically different from that in the blank control group. And there was no statistically difference between two LMW fucoidans in antiviral activity. In vivo, LMW fucoidans could prolong the survival time of virus-infected mice, and could improve the lung index of virus-infected mice significantly, which have statistical differences with the control group significantly(p < 0.01). However, the survival time of the two LMW fucoidans was not statistically significant(p > 0.05). In this study, it was shown that both of two LMW fucoidans(LF1, LF2) could increase the thymus index, spleen index, phagocytic index, phagocytosis coefficient and half hemolysin value in middle and high doses, which suggested that LMW fucoidans could play an antiviral role by improving the quality of immune organs, improving immune cell phagocytosis and humoral immunity.展开更多
We developed an HPLC method for analysis of the monosaccharide composition of fucoidans. The fucoidan was hydrolyzed into monosaccharides with 2 mol/L trifluoroacetic acid. Using ribose as the internal standard, the m...We developed an HPLC method for analysis of the monosaccharide composition of fucoidans. The fucoidan was hydrolyzed into monosaccharides with 2 mol/L trifluoroacetic acid. Using ribose as the internal standard, the monosaecharide derivatives, obtained with 1-Phenyl-3-methyl-5- pyrazolone （PMP）, were separated by reverse-phase HPLC using a gradient elution process, and monitored by ultraviolet detection at 245 nm. In the concentration range of 0.1-2.0 mmol/L, the peak area of each monosaccharide had a good linear relationship with its concentration （r^2〉0.998）. The average recoveries of mannose, rhamnose, glucuronic acid, glucose, galactose, xylose, and fucose were 86.2%, 95.1%, 62.5%, 102.0%, 94.8%, 66.6%, and 105.1%, respectively. This method was accurate and had good reproducibility and could be used to determine the monosaccharide contents of fucoidans.展开更多
Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminaria japonica, an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, ...Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminaria japonica, an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, phosphorylated, and aminated fucoidan) was examined using in-vitro anticoagulant systems. The correlation between chemical variations within the fucoidan group and anticoagulant activity was determined. The in-vitro anticoagulant properties of fucoidan and its derivatives were determined by measuring activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT). The results indicate anticoagulant activity in all samples using APTT and TT assays; however, only the fucoidan derivatives affected the PT assay. Thus, the fucoidan derivatives were able to inhibit both intrinsic and extrinsic blood coagulants. Fucoidan (FPS) and its derivatives presented better anticoagulant activity than low molecular weight fucoidan (DFPS) and its derivatives, suggesting that molecular weight and proper conformation are contributing factors for anticoagulant activity of polysaccharides. Amino groups have a positive charge and can thus change the charge density of fucoidan. Accordingly, among the tested samples, aminated fucoidan (NF) was the most active reflecting the importance of charge density for anticoagulant activity. Available data obtained using in-vitro models suggest that the sulfate content, sulfate/total-sugar ratio, molecular weight, and the substituted group of fucoidan are important factors for anticoagulant activity but that the influence of sulfate, phosphate and amino groups on anticoagulant activity was different.展开更多
The antithrombotic and antiplatelet effects of two fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica were compared in order to examine the influence of chemical charact...The antithrombotic and antiplatelet effects of two fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica were compared in order to examine the influence of chemical character on their antithrombotic activity and the possible mechanism. Both LMW fucoidan fractions exhibited favorable antithrombotic activity in an Fecl3-induced arterial thrombosis. The antithrombotic activity of LMW fucoidan was related with decrease of TXB2 and whole blood viscosity and hematocrit. LMW fucoidan showed a correlation between anticoagulant, antiaggregant and antithrombotic effects in vivo. For LMW fucoidan, antithrombotic activity required high dose of 5-10 nmol kg-1, concomitantly with increase in anticoagulant activity and inhibition of platelet aggregation. Administration of LMW fucoidan significantly promoted the 6-keto-PGF1α content and decreased the TXB2 content, indicating its inhibition of tissue factor pathway and regulation of metabolism of arachidonic acid. By comparison, highly sulfated fucoidan LF2 with Mw 3900 seemed to be a more suitable choice for antithrombotic drug for its antithrombotic activity accompanied with specific inhibitory activity on platelet aggregation, low anticoagulant activity and low hemorrhagic risk in vivo.展开更多
Summary： Fucoidan is one of the main bioactive components of polysaccharides. The current study was focused on the anti-tumor effects of fucoidan on human heptoma cell line HepG2 and the possible mechanisms. Fucoidan...Summary： Fucoidan is one of the main bioactive components of polysaccharides. The current study was focused on the anti-tumor effects of fucoidan on human heptoma cell line HepG2 and the possible mechanisms. Fucoidan treatment resulted in cell cycle arrest and apoptosis of HepG2 cells in a dose-dependent manner detected by MTT assay, flow cytometry and fluorescent microscopy. The results of flow cytometric analysis revealed that fucoidan induced G2/M arrest in the cell cycle progression. Hoechst 33258 and Annexin V/PI staining results showed that the apoptotic cell number was increased, which was associated with a dose-dependent up-regulation of Bax and down-regulation of Bcl-2 and p-Stat3. In parallel, the up-regulation of p53 and the increase in reactive oxygen species were also observed, Which may play important roles in the inhibition of HepG2 growth by fucoidan. In the meantime, Cyelin B 1 and CDK1 were down-regulated by fucoidan treatment. Down-regulation of p-Stat3 by fucoidan resulted in apoptosis and an increase in ROS in response to fucoidan exposure. We therefore concluded that fucoidan induces apoptosis through the down-regulation of p-Stat3. These results suggest that fucoidan may be used as a novel anti-cancer agent for hepatocarcinoma.展开更多
Fucoidan is an active component of seaweed, which inhibits proliferation and induces apoptosis of several tumor cells while the detailed mechanisms underlying this process are still not clear. In this study, the effec...Fucoidan is an active component of seaweed, which inhibits proliferation and induces apoptosis of several tumor cells while the detailed mechanisms underlying this process are still not clear. In this study, the effect of Fucoidan on the proliferation and apoptosis of human breast cancer MCF-7 cells and the molecular mechanism of Fucoidan action were investigated. Viable cell number of MCF-7 cells was decreased by Fucoidan treatment in a dose-dependent manner as measured by MTT assay. Fucoidan treatment resulted in G1 phase arrest of MCF-7 cells as revealed by flow cytometry, which was associated with the decrease in the gene expression of cyclin D 1 and CDK-4. Annexin V/PI staining results showed that the number of apoptotic cells was associated with regulation of cytochrome C, cas- pase-8, Bax and Bcl-2 at transcriptional and translational levels. Both morphologic observation and Hoechst 33258 assay results confirmed the pro-apoptotic effect of Fucoidan. Meanwhile, the ROS pro- duction was also increased by Fucoidan treatment, which suggested that Fucoidan induced oxidative damage in MCF-7 cells. The results of present study demonstrated that Fucoidan could induce GI phase arrest and apoptosis in MCF-7 cells through regulating the cell cycle and apoptosis-related genes or proteins expression, and ROS generation is also involved in these processes.展开更多
Fucoidan, a polysaccharide containing abundant fucose and sulfate ester group, was prepared from Laminaria japonica. In order to obtain fucoidan-degrading enzyme, bacteria capable of degrading fucoidan were screened f...Fucoidan, a polysaccharide containing abundant fucose and sulfate ester group, was prepared from Laminaria japonica. In order to obtain fucoidan-degrading enzyme, bacteria capable of degrading fucoidan were screened from kelp. A bacterial strain named RC2-3 was obtained, which degraded fucoidan by the maximum extent of 54% ± 1.3%, the highest among all bacterial isolates. High-performance size exclusion chromatography(HPSEC) showed that the molecular weight of fucoidan was gradually reduced by RC2-3 with culturing time, suggesting the production of fucoidan-degrading enzyme by RC2-3. Phylogenetic analysis of partial 16S ribosomal RNA gene(16S rDNA) sequence showed that RC2-3 belonged to the family Flavobacteriaceae. However, it showed different physiological and biochemical characteristics from the known Flavobacteriaceae members producing fucoidan-degrading enzyme, thus RC2-3 was proposed to be a new member of this family.展开更多
In this study, a fucoidan-based theranostic nanogel(CFN-gel) consisting of a fucoidan backbone, redox-responsive cleavable linker and photosensitizer is developed to achieve acti-vatable near-infrared fluorescence ima...In this study, a fucoidan-based theranostic nanogel(CFN-gel) consisting of a fucoidan backbone, redox-responsive cleavable linker and photosensitizer is developed to achieve acti-vatable near-infrared fluorescence imaging of tumor sites and an enhanced photodynamic therapy(PDT) to induce the com-plete death of cancer cells. A CFN-gel has nanomolar a nity for P-selectin, which is overexpressed on the surface of tumor neovascular endothelial cells as well as many other cancer cells. Therefore, a CFN-gel can enhance tumor accumulation through P-selectin targeting and the enhanced permeation and retention e ect. Moreover, a CFN-gel is non-fluorescent and non-phototoxic upon its systemic administration due to the aggregation-induced self-quenching in its fluorescence and singlet oxygen generation. After internalization into cancer cells and tumor neovascular endothelial cells, its photoactivity is recovered in response to the intracellular redox potential, thereby enabling selective near-infrared fluorescence imaging and an enhanced PDT of tumors. Since a CFN-gel also shows nanomolar a nity for the vascular endothelial growth factor, it also provides a significant anti-tumor e ect in the absence of light treatment in vivo. Our study indicates that a fucoidan-based theranostic nanogel is a new theranostic material for imaging and treating cancer with high e cacy and specificity.展开更多
Obesity is an escalating global pandemic posing a serious threat to human health.The intervention therapy using weight-reducing drugs,accompanied by lifestyle modification,is a strategy for the treatment of obesity.In...Obesity is an escalating global pandemic posing a serious threat to human health.The intervention therapy using weight-reducing drugs,accompanied by lifestyle modification,is a strategy for the treatment of obesity.In the present study,we explored the role of fucoidan,a seaweed compound,on high-fat diet(HFD)-induced obesity in mice.We found that fucoidan treatment significantly reduced the body fat and caused redistribution of visceral and subcutaneous fat in HFD-fed mice.Meanwhile,fucoidan treatment inhibited adipocyte hypertrophy and inflammation in adipose tissue.Collectively,these results suggest that fucoidan may be a promising treatment for obesity and obesity-induced complications.展开更多
In Japan, S-1 plus cisplatin has become a standard regimen for the treatment of unresectable advanced gastric cancer;however, many patients are unable to continue effective chemotherapy because of the regimen’s sever...In Japan, S-1 plus cisplatin has become a standard regimen for the treatment of unresectable advanced gastric cancer;however, many patients are unable to continue effective chemotherapy because of the regimen’s severe side effects. Thus, control of drug toxicity is key to prolonging patient survival. Fucoidan is a major sulfated polysaccharide found in brown seaweeds and has a wide range of biological activities. In the present study, we analyzed the effect of fucoidan on suppressing the toxicity of chemotherapy drugs. Twenty-four patients with unresectable advanced gastric cancer underwent treatment with S-1 plus cisplatin and were randomly allocated into a fucoidan treatment group (n = 12) or a control group without fucoidan treatment (n = 12). The study results demonstrated that fucoidan controlled the occurrence of fatigue during chemotherapy and patients could continue chemotherapy for longer time periods by maintaining the patients’ favorable nourishment status. As a result, the survival of patients with fucoidan treatment was longer than that of patients without fucoidan. Thus, fucoidan should be included as a key food supplement for patients with gastrointestinal carcinomas who are suffering from the adverse side effects of chemotherapy.展开更多
基金supported by the Ocean Public Welfare Scientific Research Project, State Ocean Administration of China (No. 201105029-9)
文摘In this study, we evaluated the chemical property and antioxidant activity of fucoidans isolated from brown algae, Laminaria japonica(LJF), Lessonia nigrescens(LNF), Lessonia trabeculata(LTF), Ascophyllum mackaii(AMF), and Ecklonia maxima(EMF). LJF was less in sulfate content(14.16%) and more in galactose and mannose content(1.08 and 0.68) than the documented early. EMF contained 20%–30% of sulfate and fucose, 0.97 in molar ratio which was lower than that of sulfate to other four fucoidans(1.21–1.41). AMF(162 kDa) and EMF(150 kDa) were the first two largest in molecular weight, which were followed by LJP(126 kDa), LNF(113 kDa) and LTF(105 kDa). The fucoidans isolated these algae showed a wide range of antioxidant activity in vitro. It was found that the reducing power of the isolated fucoidans was positively correlated with their sulfate content and molecular weight. In addition, LNF and LTF at low concentrations exhibited high superoxide and hydroxyl radical scavenging activity. This demonstrated that low molecular weight fucoidans may perform a high antioxidant activity.
基金supported by the Special Fund for Clinical Scientific Research of Shandong Medical Association(No.YXH2020ZX058).
文摘This study was carried out explore the mechanism underlying the inhibition of platelet activation by kelp fucoidans in deep venous thrombosis(DVT)mouse.In the control and sham mice,the walls of deep vein were regular and smooth with intact intima,myometrium and adventitia.The blood vessel was wrapped with the tissue and there was no thrombosis in the lumen.In the DVT model,the wall was uneven with thicken intima,myometrium and adventitia.After treated with fucoidans LF1 and LF2,the thrombus was dissolved and the blood vessel was recanalized.Compared with the control group,the ROS content,ET-1 and VWF content and the expression of PKC-βand NF-κB in the model were significantly higher(P<0.05);these levels were significantly reduced following treatments with LF2 and LF1.Compared with H_(2)O_(2)treated-HUVECs,combined LF1 and LF2 treatment resulted in significant decrease in the expression of PKC-β,NF-κB,VWF and TM protein(P<0.05).It is clear that LF1 and LF2 reduces DVT-induced ET-1,VWF and TM expressions and production of ROS,thus inhibiting the activation of PKC-β/NF-κB signal pathway and the activation of coagulation system and ultimately reducing the formation of venous thrombus.
基金This study was supported by the National Key Research and Development Program of China(No.2018YFC0311203)the Key Research and Development Plan in Shandong Province(No.2016YYSP017).
文摘In this study,fucoidans were extracted from the sea cucumber Thelenota ananas(Ta-FUCs)by enzymatic degradation.Four products with molecular weights of 1380.3,524.0,182.4,and 110.3 kDa were obtained,and the Ta-FUC showing optimal anti-adipogenic activities was determined.Results of MTT and Oil red O staining analyses showed that the Ta-FUCs inhibited the proliferation and differentiation of 3T3-L1 adipocytes.Futhermore,Ta-FUCs significantly downregulated the key transcriptional factors,such as SREBP-1c,PPARγ,and C/EBPαof adipocytes.The Ta-FUCs also activated Wnt/β-catenin pathway-related genes,such asβ-catenin,LRP5,and FrZ.The Ta-FUCs suppressed lipid accumulation in 3T3-L1 adipocytes possibly by decreasing the expression of genes ACC,FAS,ME,GPAT,DGAT,and PILN,which are important in the synthesis of fatty acids and triglycerides;and by increasing the expression of genes PPARα,CPT-1α,and ACOX,which are crucial in fatty acidβ-oxidation.The anti-adipogenic activities initially increased and then declined with decreasing molecular weight.Among the Ta-FUCs,the 182.4 kDa Ta-FUC exhibited optimal bioactivities.This study reports for the first time that Ta-FUCs can prevent obesity by regulating the differentiation and lipid accumulation of adipocytes.
基金supported by the National Natural Science Foundation of China under contract No.30471349Guangdong Natural Science Foundation under contract No.011256.
文摘Five fucoidan fractions from Laminaria japonica with different sulfate content and molecular weight were prepared by anion-exchange chromatography and mild acid hydrolysis. Their antioxidant effects on azo radicals 2-2＇-Azobis （2-amidinopropane） dihydrochloride （AAPH） induced oxidation of human low-density lipoprotein （LDL） were evaluated by monitoring cholesteryl ester hydroperoxides （CHL-OOH） formation kinetics through reverse-phase high performance liquid chromatography （RP-HPLC） analysis. Fucoidan F - C with a low molecular mass of 2 000 ～8 000 and a sulfate content of 24.3% had much stronger protective antioxidant effect than other four fucoidan fractions on the hydrophilic radical AAPH induced LDL oxidation. However, the highly sulfated fucoidan fraction L - B with a molecular mass of 20 000 was completely ineffective in protecting LDL from the AAPH induced oxidation. The results suggested that both molecular mass and sulfate content of fucoidan played very important roles in their effects on the AAPH induced LDL oxidation.
文摘Objective:To investigate the therapeutic adjuvant potential of fucoidan in cervical cancer and to evaluate its efficacy in combination with immunotherapy.Methods:Fucoidan extracted from Fucus vesiculosus was dissolved in phosphate buffered saline and used to treat TC-1 cervical cancer cells in vitro as well as tumor-bearing C57BL/6 mice in vivo.Mice were divided into four groups:the vehicle control group,the mRNA therapy-alone group,the fucoidan-only group,and the combination group.MAPK signaling proteins(p-ERK,T-ERK,p-p38)were analyzed by Western blotting assays.T cell surface markers and intracellular cytokines in splenocytes were assessed by flow cytometry,and plasma cytokine levels were measured by ELISA.Results:Fucoidan decreased the p-ERK/T-ERK ratio and p-p38.Fucoidan combined with mRNA therapy did not significantly affect CD4^(+)T-cell activation but reduced CD8^(+)T-cell activation compared with mRNA therapy alone.MCP-1 and IFN-γwere significantly reduced in the combination therapy group compared with mRNA therapy alone,while IL-6,TNF-α,perforin,and granzyme B did not show significant changes between the two groups.Conclusions:These findings suggest that fucoidan could inhibit excessive T cell activation and cytokine production by suppressing MAPK p-p38 protein expression.
基金funded by the National Natural Science Foundation of China(32102733)the Zhejiang Provincial Natural Science Foundation of China(LQ22C180004)the Longyan University&Fujian Provincial Key Laboratory for Prevention and Control of Animal Infectious Diseases and Biotechnology(ZDSYS2022002)。
文摘Mastitis often occurs during women's lactation period,causing great psychological and physical pain to women.Fucoidan,a sulfated polysaccharide obtained from brown algae,has much broader biological properties.However,the roles of fucoidan in lipopolysaccharides(LPS)-induced mastitis are still undiscovered.The present study was aimed to evaluate the influences of fucoidan on LPS-induced mouse mastitis and investigate its possible mechanisms.The expression profiles of fucoidan acting on mastitis were analyzed by network pharmacology.Additionally,mechanism experiments verified the mechanism of fucoidan on mastitis.The results of in vivo study displayed that the treatment of fucoidan to LPS-stimulated mouse mastitis decreased the inflammatory damage,proinflammatory cytokines level and repaired the completeness of bloodmilk barrier.In the study of mouse mammary epithelial cells,fucoidan suppressed the secretion of reactive oxygen species(ROS)and enhanced the activity of antioxidant enzymes.Molecular experiments suggested that fucoidan promoted nuclear factor erythroid 2-related factor 2(Nrf2)nuclear import and autophagy via activating the adenosine 5'-monophosphate-activated protein kinase(AMPK)signaling pathway.The above results indicated that in mastitis,fucoidan promoted Nrf2 nuclear import and autophagy via activating the AMPK signaling pathway,thereby suppressing oxidative stress and inflammatory injury to the mammary glands and protecting the blood-milk barrier.
文摘目的:探讨ERK信号通路在内质网应激时由A类清道夫受体(SR-A)介导的细胞凋亡中的作用。方法:ERK磷酸化和葡萄糖相关蛋白78(GRP78)的表达用Western blot方法检测,细胞活性用四甲基噻唑蓝(MTT)实验检测,同时应用Annexin V FITC/PI双染流式细胞术检测细胞凋亡率。结果:Western blot结果显示,fucoidan可以持续激活ERK,并且在1～4h达到最强,这种作用在SR-A基因敲除小鼠的腹腔巨噬细胞中明显减弱。用PD98059阻断ERK信号途径后,内质网应激时fucoidan诱导RAW264.7细胞凋亡率明显降低。结论:在发生内质网应激时,fucoidan与SR-A结合后激活ERK信号通路,可能是促进巨噬细胞凋亡的机制之一。
文摘AIM:To evaluate the protective effects of fucoidan on oxidative stress-induced barrier disruption in human intestinal epithelial cells.METHODS:In Caco-2 cell monolayer models,the disruption of barrier function by oxidative stress is mediated by H2O2.The integrity of polarized Caco-2 cell monolayers was determined by measuring the transepithelial resistance(TER)and permeability was estimated by measuring the paracellular transport of FITC-labeled4-kDa dextran(FD4).The protective effects of fucoidan on epithelial barrier functions on polarized Caco-2 cell monolayers were evaluated by TER and FD4 flux.The expression of tight junction(TJ)proteins was assessed using reverse-transcription polymerase chain reaction(RT-PCR)and immunofluorescence staining.RESULTS:Without H2O2treatment,fucoidan significantly increased the TER compared to control(P<0.05),indicating a direct enhancement of intestinal epithelial barrier function.Next,H2O2disrupted the epithelial barrier function in a time-dependent manner.Fucoidan prevented the H2O2-induced destruction in a dosedependent manner.Fucoidan significantly decreased H2O2-induced FD4 flux(P<0.01),indicating the prevention of disruption in paracellular permeability.RTPCR showed that Caco-2 cells endogenously expressed claudin-1 and-2,and occludin and that H2O2reduced the mRNA expression of these TJ proteins.Treatment with fucoidan attenuated the reduction in the expressions of claudin-1 and claudin-2 but not occludin.Immunofluorescence staining revealed that the expression of claudin-1 was intact and high on the cell surface.H2O2disrupted the integrity of claudin-1.Treatment with fucoidan dramatically attenuated the expression of claudin-1.CONCLUSION:Fucoidan enhanced intestinal epithelial barrier function by upregulating the expression of claudin-1.Thus,fucoidan may be an appropriate therapy for the treatment of inflammatory bowel diseases.
基金supported by grants from the Technology Development Project (No. 201505022)the NSFC Shandong Joint Fund (No. U1406402)National Natural Science Foundation of China (No. 31371759)
文摘The antiviral activity in vitro and in vivo and the effect of the immune system of two fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica(LMW fucoidans) were investigated in order to examine the possible mechanism. In vitro, I-type influenza virus, adenovirus and Parainfluenza virus I were used to infect Hep-2, Hela and MDCK cells, respectively. And 50% tissue culture infective dose was calculated to detect the antiviral activity of two LMW fucoidans. The results indicated that compared with the control group, 2 kinds of LMW fucoidans had remarkable antiviral activity in vitro in middle and high doses, while at low doses, the antiviral activity of 2 kinds of LMW fucoidans was not statistically different from that in the blank control group. And there was no statistically difference between two LMW fucoidans in antiviral activity. In vivo, LMW fucoidans could prolong the survival time of virus-infected mice, and could improve the lung index of virus-infected mice significantly, which have statistical differences with the control group significantly(p < 0.01). However, the survival time of the two LMW fucoidans was not statistically significant(p > 0.05). In this study, it was shown that both of two LMW fucoidans(LF1, LF2) could increase the thymus index, spleen index, phagocytic index, phagocytosis coefficient and half hemolysin value in middle and high doses, which suggested that LMW fucoidans could play an antiviral role by improving the quality of immune organs, improving immune cell phagocytosis and humoral immunity.
基金Supported by the Key Technology Research & Development Program of Shandong Province (No 2007GG1005007)
文摘We developed an HPLC method for analysis of the monosaccharide composition of fucoidans. The fucoidan was hydrolyzed into monosaccharides with 2 mol/L trifluoroacetic acid. Using ribose as the internal standard, the monosaecharide derivatives, obtained with 1-Phenyl-3-methyl-5- pyrazolone （PMP）, were separated by reverse-phase HPLC using a gradient elution process, and monitored by ultraviolet detection at 245 nm. In the concentration range of 0.1-2.0 mmol/L, the peak area of each monosaccharide had a good linear relationship with its concentration （r^2〉0.998）. The average recoveries of mannose, rhamnose, glucuronic acid, glucose, galactose, xylose, and fucose were 86.2%, 95.1%, 62.5%, 102.0%, 94.8%, 66.6%, and 105.1%, respectively. This method was accurate and had good reproducibility and could be used to determine the monosaccharide contents of fucoidans.
基金Supported by the Ocean Public Welfare Scientific Research Project, State Oceanic Administration of the People's Republic of China (No. 201005024)
文摘Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminaria japonica, an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, phosphorylated, and aminated fucoidan) was examined using in-vitro anticoagulant systems. The correlation between chemical variations within the fucoidan group and anticoagulant activity was determined. The in-vitro anticoagulant properties of fucoidan and its derivatives were determined by measuring activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT). The results indicate anticoagulant activity in all samples using APTT and TT assays; however, only the fucoidan derivatives affected the PT assay. Thus, the fucoidan derivatives were able to inhibit both intrinsic and extrinsic blood coagulants. Fucoidan (FPS) and its derivatives presented better anticoagulant activity than low molecular weight fucoidan (DFPS) and its derivatives, suggesting that molecular weight and proper conformation are contributing factors for anticoagulant activity of polysaccharides. Amino groups have a positive charge and can thus change the charge density of fucoidan. Accordingly, among the tested samples, aminated fucoidan (NF) was the most active reflecting the importance of charge density for anticoagulant activity. Available data obtained using in-vitro models suggest that the sulfate content, sulfate/total-sugar ratio, molecular weight, and the substituted group of fucoidan are important factors for anticoagulant activity but that the influence of sulfate, phosphate and amino groups on anticoagulant activity was different.
基金supported in part by the Notional Natural Science Foundation of China (No.30800858)the Shandong Natural Science Foundation (No.ZR2010 CQ020)
文摘The antithrombotic and antiplatelet effects of two fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica were compared in order to examine the influence of chemical character on their antithrombotic activity and the possible mechanism. Both LMW fucoidan fractions exhibited favorable antithrombotic activity in an Fecl3-induced arterial thrombosis. The antithrombotic activity of LMW fucoidan was related with decrease of TXB2 and whole blood viscosity and hematocrit. LMW fucoidan showed a correlation between anticoagulant, antiaggregant and antithrombotic effects in vivo. For LMW fucoidan, antithrombotic activity required high dose of 5-10 nmol kg-1, concomitantly with increase in anticoagulant activity and inhibition of platelet aggregation. Administration of LMW fucoidan significantly promoted the 6-keto-PGF1α content and decreased the TXB2 content, indicating its inhibition of tissue factor pathway and regulation of metabolism of arachidonic acid. By comparison, highly sulfated fucoidan LF2 with Mw 3900 seemed to be a more suitable choice for antithrombotic drug for its antithrombotic activity accompanied with specific inhibitory activity on platelet aggregation, low anticoagulant activity and low hemorrhagic risk in vivo.
基金supported by grants from the Wuhan Municipal Science and Technology Research Project(No.201260523185)the Public Science and Technology Research Funds Projects of Ocean(No.201005013)
文摘Summary： Fucoidan is one of the main bioactive components of polysaccharides. The current study was focused on the anti-tumor effects of fucoidan on human heptoma cell line HepG2 and the possible mechanisms. Fucoidan treatment resulted in cell cycle arrest and apoptosis of HepG2 cells in a dose-dependent manner detected by MTT assay, flow cytometry and fluorescent microscopy. The results of flow cytometric analysis revealed that fucoidan induced G2/M arrest in the cell cycle progression. Hoechst 33258 and Annexin V/PI staining results showed that the apoptotic cell number was increased, which was associated with a dose-dependent up-regulation of Bax and down-regulation of Bcl-2 and p-Stat3. In parallel, the up-regulation of p53 and the increase in reactive oxygen species were also observed, Which may play important roles in the inhibition of HepG2 growth by fucoidan. In the meantime, Cyelin B 1 and CDK1 were down-regulated by fucoidan treatment. Down-regulation of p-Stat3 by fucoidan resulted in apoptosis and an increase in ROS in response to fucoidan exposure. We therefore concluded that fucoidan induces apoptosis through the down-regulation of p-Stat3. These results suggest that fucoidan may be used as a novel anti-cancer agent for hepatocarcinoma.
基金supported by grants from The National Maritime Bureau Public Science and Technology Research Funds Projects of Ocean(No.201005013)the Wuhan Municipal Science and Technology Research Project of China(No.201260523185)
文摘Fucoidan is an active component of seaweed, which inhibits proliferation and induces apoptosis of several tumor cells while the detailed mechanisms underlying this process are still not clear. In this study, the effect of Fucoidan on the proliferation and apoptosis of human breast cancer MCF-7 cells and the molecular mechanism of Fucoidan action were investigated. Viable cell number of MCF-7 cells was decreased by Fucoidan treatment in a dose-dependent manner as measured by MTT assay. Fucoidan treatment resulted in G1 phase arrest of MCF-7 cells as revealed by flow cytometry, which was associated with the decrease in the gene expression of cyclin D 1 and CDK-4. Annexin V/PI staining results showed that the number of apoptotic cells was associated with regulation of cytochrome C, cas- pase-8, Bax and Bcl-2 at transcriptional and translational levels. Both morphologic observation and Hoechst 33258 assay results confirmed the pro-apoptotic effect of Fucoidan. Meanwhile, the ROS pro- duction was also increased by Fucoidan treatment, which suggested that Fucoidan induced oxidative damage in MCF-7 cells. The results of present study demonstrated that Fucoidan could induce GI phase arrest and apoptosis in MCF-7 cells through regulating the cell cycle and apoptosis-related genes or proteins expression, and ROS generation is also involved in these processes.
基金the financial support from the National Natural Science Foundation of China(No.30800858)
文摘Fucoidan, a polysaccharide containing abundant fucose and sulfate ester group, was prepared from Laminaria japonica. In order to obtain fucoidan-degrading enzyme, bacteria capable of degrading fucoidan were screened from kelp. A bacterial strain named RC2-3 was obtained, which degraded fucoidan by the maximum extent of 54% ± 1.3%, the highest among all bacterial isolates. High-performance size exclusion chromatography(HPSEC) showed that the molecular weight of fucoidan was gradually reduced by RC2-3 with culturing time, suggesting the production of fucoidan-degrading enzyme by RC2-3. Phylogenetic analysis of partial 16S ribosomal RNA gene(16S rDNA) sequence showed that RC2-3 belonged to the family Flavobacteriaceae. However, it showed different physiological and biochemical characteristics from the known Flavobacteriaceae members producing fucoidan-degrading enzyme, thus RC2-3 was proposed to be a new member of this family.
基金supported by the Ministry of Oceans and Fisheries,Korea(the project title:Development of marine material based near infrared fluorophore complex and diagnostic imaging instruments)by a Grant(1910070)from the National Cancer Center
文摘In this study, a fucoidan-based theranostic nanogel(CFN-gel) consisting of a fucoidan backbone, redox-responsive cleavable linker and photosensitizer is developed to achieve acti-vatable near-infrared fluorescence imaging of tumor sites and an enhanced photodynamic therapy(PDT) to induce the com-plete death of cancer cells. A CFN-gel has nanomolar a nity for P-selectin, which is overexpressed on the surface of tumor neovascular endothelial cells as well as many other cancer cells. Therefore, a CFN-gel can enhance tumor accumulation through P-selectin targeting and the enhanced permeation and retention e ect. Moreover, a CFN-gel is non-fluorescent and non-phototoxic upon its systemic administration due to the aggregation-induced self-quenching in its fluorescence and singlet oxygen generation. After internalization into cancer cells and tumor neovascular endothelial cells, its photoactivity is recovered in response to the intracellular redox potential, thereby enabling selective near-infrared fluorescence imaging and an enhanced PDT of tumors. Since a CFN-gel also shows nanomolar a nity for the vascular endothelial growth factor, it also provides a significant anti-tumor e ect in the absence of light treatment in vivo. Our study indicates that a fucoidan-based theranostic nanogel is a new theranostic material for imaging and treating cancer with high e cacy and specificity.
基金supported by the grants from the National Natural Science Foundation of China(81830011,81670418,and 91739304 to Q.C.,81770417 to X.Z.,81870371 to J.B.,and 81670263 to X.L.)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(18KJA310003 to J.B.and 15KJA310001 to X.L.).
文摘Obesity is an escalating global pandemic posing a serious threat to human health.The intervention therapy using weight-reducing drugs,accompanied by lifestyle modification,is a strategy for the treatment of obesity.In the present study,we explored the role of fucoidan,a seaweed compound,on high-fat diet(HFD)-induced obesity in mice.We found that fucoidan treatment significantly reduced the body fat and caused redistribution of visceral and subcutaneous fat in HFD-fed mice.Meanwhile,fucoidan treatment inhibited adipocyte hypertrophy and inflammation in adipose tissue.Collectively,these results suggest that fucoidan may be a promising treatment for obesity and obesity-induced complications.
文摘In Japan, S-1 plus cisplatin has become a standard regimen for the treatment of unresectable advanced gastric cancer;however, many patients are unable to continue effective chemotherapy because of the regimen’s severe side effects. Thus, control of drug toxicity is key to prolonging patient survival. Fucoidan is a major sulfated polysaccharide found in brown seaweeds and has a wide range of biological activities. In the present study, we analyzed the effect of fucoidan on suppressing the toxicity of chemotherapy drugs. Twenty-four patients with unresectable advanced gastric cancer underwent treatment with S-1 plus cisplatin and were randomly allocated into a fucoidan treatment group (n = 12) or a control group without fucoidan treatment (n = 12). The study results demonstrated that fucoidan controlled the occurrence of fatigue during chemotherapy and patients could continue chemotherapy for longer time periods by maintaining the patients’ favorable nourishment status. As a result, the survival of patients with fucoidan treatment was longer than that of patients without fucoidan. Thus, fucoidan should be included as a key food supplement for patients with gastrointestinal carcinomas who are suffering from the adverse side effects of chemotherapy.
