Transcriptome analysis of bovine lymphocytes stimulated by Atractylodis macrocephalae Koidz. polysaccharides in vitro

Research progress on extraction, separation, structure, and biological activities of polysaccharides from the genus Atractylodes: A review

Plants of the genus Atractylodes are perennial herbaceous plants in the family Asteraceae, whose rhizome is often used in the production of medicines and health products. There are 6 main species in this genus, namely A. macrocephala, A. lancea, A. chinensis, A. carlinoides, A. koreana and A. japonica. Among them, A. lancea and A. macrocephala are the most extensively investigated. Polysaccharides as the main active ingredients extracted and isolated from plants in this genus, show good pharmacological activities in vivo and in vitro, such as immunomodulatory, antioxidant, antidiabetic and intestinal protective activities. The pharmacological activities of polysaccharides are closely related to their extraction methods and physicochemical properties. This article discusses the extraction and separation methods, molecular weight, monosaccharide composition, chemical structure characteristics and pharmacological activities of polysaccharides from the genus Atractylodes. Furthermore, a comparative analysis of the relationship of monosaccharide composition, relative molecular weight and structural modifications with the pharmacological activities of polysaccharides of the genus Atractylodes was carried out, which provided a reference for the development and utility of polysaccharides.

Immunomodulatory effect of Atractylodis macrocephala Koidz. polysaccharides in vitro

Vaccination is still the main method of preventing most infectious diseases, but there are inefficiencies and inaccuracies in immunization. Studies have reported that Atractylodis macrocephalae Koidz. polysaccharides (RAMP) have immunomodulatory effects, but the mechanisms involved in whether they can modulate the immune response in chickens are not yet clear. The aim of this study was to investigate the effect of RAMP on lymphocytes functions by analyzing cell proliferation, cell cycle, mRNA expression of cytokines and CD4 +/CD8 + ratio. To identify potential molecules involved in immune regulation, we performed a comprehensive transcriptome profiling of chicken lymphocytes. In addition, the adjuvant effect of RAMP was evaluated by detecting indicators of hemagglutination inhibition. When lymphocytes were cultured with RAMP in vitro, the proliferation rate of lymphocytes was increased (P < 0.01), more cells in S phase and G2/M phase (P < 0.01) and the mRNA expression of IFN-γ was upregulated (P < 0.05), while the mRNA expression of TGF-β (P < 0.01) and IL-4 (P < 0.05) was downregulated and the CD4 +/CD8 + ratio was increased (P < 0.05). Transcriptomic results showed that RAMP increased the expression of HIST1H46 (P < 0.05) and CENPP (P < 0.05). Validation of qPCR showed that RAMP may play an important role in regulating cellular immunity by downregulating the Notch pathway. The results also showed that RAMP could increase the serum Newcastle disease virus antibody levels in chickens. These data suggest that RAMP could enhance immune function of lymphocytes and was a candidate vaccine adjuvant in chickens.

The Molecular Mechanism of Yam Polysaccharide Protected H2O2-Induced Oxidative Damage in IEC-6 Cells

Oxidative stress is involved in maintaining homeostasis of the body, and an in-depth study of its mechanism of action is beneficial for the prevention of chronic illnesses. This study aimed to investigate the protective mechanism of yam polysaccharide (CYP) against H₂O₂-induced oxidative damage by an RNA-seq technique. The expression of genes and the function of the genome in the process of oxidative damage by H₂O₂ in IEC-6 cells were explored through transcriptomic analysis. The results illustrated that H₂O₂ damaged cells by promoting cell differentiation and affecting tight junction proteins, and CYP could achieve cell protection via restraining the activation of the MAPK signaling pathway. RNA-seq analysis revealed that H₂O₂ may damage cells by promoting the IL-17 signaling pathway and the MAPK signaling pathway and so forth. The Western blot showed that the pretreatment of CYP could restrain the activation of the MAPK signaling pathway. In summary, this study demonstrates that the efficacy of CYP in modulating the MAPK signaling pathway against excessive oxidative stress, with a corresponding preventive role against injury to the intestinal barrier. It provides a new perspective for the understanding of the preventive role of CYP on intestinal damage. These findings suggest that CYP could be used as oxidation protectant and may have potential application prospects in the food and pharmaceutical industries.

Transcriptome analysis reveals immune and metabolic regulation effects of Poria cocos polysaccharides on Bombyx mori larvae

Poria cocos polysaccharides (PS) have been used as Chinese traditional medicine with various pharmacological effects, including antiviral, anti-oxidative, and immunomodulatory activities. Herein Bombyx mori silkworm was used as a model animal to evaluate the immunomodulatory effects of PS via detecting the changes of innate immune parameters and explore the underlying molecular mechanism of the immunoregulatory effect of PS using Illumina HiSeq Xten platform. The results presented here demonstrated that a hemocoel injection of PS significantly enhanced the cellular immunity of silkworm, including hemocyte phagocytosis, microaggregation, and spreading ability. A total of 335 differentially expressed genes (DEGs) were screened, including 214 upregulated genes and 121 downregulated genes by differential expression analysis. Gene annotation and enrichment analyses showed that many DEGs related to immune signal recognition, detoxification, proPO activation, carbohydrate metabolism, and lipid metabolism were significantly upregulated in the treatment group. The Kyoto Encyclopedia of Genes and Genomes-based Gene Set Enrichment Analysis also revealed that the more highly expressed gene sets in the PS treatment silkworm were mainly related to immune signal transduction pathways and energy metabolism. In addition, the activity of four enzymes related to immunity and energy metabolism—including phenoloxidase, glucose-6-phosphate dehydrogenase, hexokinase, and fatty acid synthetase—were all significantly increased in the larvae injected with PS. We performed qRT-PCR to examine the expression profile of immune and metabolic-related genes, which further verified the reliability of our transcriptome data and suggested that PS can regulate the immunity of silkworm by enhancing the cellular immunity and modulating the expression levels of genes related to immune responses and physiological metabolism. These findings will lay a scientific foundation for the use of PS as an immunomodulator in disease prevention in human beings or animals.

Isolation, structure and bioactivity of polysaccharides from Atractylodes macrocephala: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Polysaccharides from Atractylodes macrocephala are important components isolated and extracted from the traditional Chinese medicine named Atractylodes macrocephala Koidz. Traditionally, A. macrocephala has been used to strengthen the spleen, benefit qi, dry dampness and promote water circulation, and prevent miscarriage. As the main components, polysaccharides from A. macrocephala have a variety of related pharmacological activities, such as the ability to regulate the gastrointestinal tract, protect the liver and so on.

AIM OF THE REVIEW

This review aims to compile the extraction and purification methods, structural characteristics and pharmacological activities of polysaccharides from A. macrocephala and the mechanisms of actions to explore the future application potential of polysaccharides from A. macrocephala.

MATERIALS AND METHODS

Valid and comprehensive relevant information was collected from China National Knowledge Infrastructure, Web of Science, Pubmed and so on.

RESULTS

More than 20 polysaccharides have been extracted from A. macrocephala, different extraction and purification methods have been described, and the composition structures and pharmacological activities of polysaccharides from A. macrocephala have been reviewed. Polysaccharides, as important components of A. macrocephala, were mainly extracted by four methods such as water decoction, ultrasonic-assisted extraction, complex enzyme method and microwave-assisted extraction, and then were obtained through decolorization, deproteinization and separation and purification by various chromatographic columns. The chemical compositions and structures of polysaccharides from A. macrocephala show diversification, and three structural formulae have been confirmed at this stage. Polysaccharides from A. macrocephala have a variety of pharmacological activities, such as immunomodulation, antitumor, antioxidant, hepatoprotection, gastrointestinal mucosa protection, neuroprotection, hypoglycemia, growth promotion and so on.

CONCLUSIONS

There is a diversity in the compositional structures of polysaccharides from A. macrocephal, which have multiple biological activities and promising applications. Therefore, further understanding of the relationship between structures and functions of polysaccharides from A. macrocephaly, and potential synergistic effects with other substances is especially important for its development and utilization.

Peucedanum praeruptorum Dunn polysaccharides regulate macrophage inflammatory response through TLR2/TLR4-mediated MAPK and NF-κB pathways

The present study was to investigate the molecular mechanisms underlying macrophage inflammatory response to polysaccharides from Peucedanum praeruptorum Dunn (PPDs) and elucidate the receptors and signaling pathways associated with PPDs-mediated macrophage activation. MTT and Griess method were performed to investigate the effects of PPDs on cell viability and NO production. Neutral red and FITC-dextran were used to determine the pinocytic and phagocytic activity. RT-qPCR and ELISA were employed to analyze the mRNA expression of inflammatory factors and production of cytokines and chemokines. RNA-seq and bioinformatics analysis were conducted to determine the underlying molecules, regulators and pathways, which were further validated by pathway inhibition and neutralization assays. The results indicated that PPDs significantly enhanced pinocytic and phagocytic activity, promoted the expression and secretion of inflammatory factors and chemokines, and boosted the expression of accessory and costimulatory molecules. RNA-Seq analysis identified 1343 DEGs, 405 GO terms and 91 KEGG pathways. IL6 and TNF were identified as hubs of connectivity in PPDs-mediated macrophage activation. "Cytokine-cytokine receptor interaction", "TNF signaling pathway", "NF-kappa B signaling pathway", "JAK-STAT signaling pathway" and "MAPK signaling pathway" were the most significant pathways. The pathway inhibition assay revealed that MAPK and NF-κB pathways were essential to macrophage activation by PPDs. TLR2 and TLR4 were uncovered to be the functional receptors and involved in recognition of PPDs. These results indicated that PPDs modulated macrophage inflammatory response mainly through TLR2/TLR4-dependent MAPK and NF-κB pathways.

Polyethylenimine-coated PLGA nanoparticles containing Angelica sinensis polysaccharide promote dendritic cells activation and associated molecular mechanisms

Cationic PLGA nanoparticles-based delivery systems have been extensively employed as nanocarriers for drugs and antigens in recent years. Herein, we investigated the effects of polyethylenimine-coated PLGA nanoparticles containing Angelica sinensis polysaccharide (ASP) system (ASP-PLGA-PEI) on dendritic cells (DCs) activation and maturation, and further explored the changes of transcriptome and underlying mechanism of DCs activation based on RNA-seq. Our results demonstrated that ASP-PLGA-PEI obviously promoted the activation and maturation of DCs. Meanwhile, RNA-seq analysis results exhibited 2812 differentially expressed genes (DEGs) between ASP-PLGA-PEI and control group, and the DCs activation by ASP-PLGA-PEI stimulation mainly related to phagosome, antigen processing and presentation, proteasome, lysosome, protein processing in endoplasmic reticulum and other pathways by KEGG pathways analysis. Furthermore, ASP-PLGA-PEI nanoparticles increased the levels of pJAK2 protein, and the expression of co-stimulatory molecules and cytokines induced by ASP-PLGA-PEI nanoparticles were decreased with the presence of the inhibitor of JAK2/STAT3 signaling pathway. In addition, the nanoparticles were internalized by DCs mainly through the clathrin-mediated endocytosis and micropinocytosis. These results suggested that the DCs activation and maturation stimulated by ASP-PLGA-PEI were regulated via a complex interaction network, in which the JAK2/STAT3 signaling pathway played a crucial role.

Administration of infectious bursal disease vaccine in Houhai acupoint promotes robust immune responses in chickens

The present study aimed to investigate Houhai acupoint (HA) administration of infectious bursal disease (IBD) vaccine in chickens and explore the underlying mechanisms. Chickens were randomly divided into 3 groups on average. Chickens in group 1 (Nape group) and group 2 (HA group) were immunized with IBD vaccine via subcutaneous injection in the nape and HA injection individually. Chickens without immunization in group 3 (Control group) served as controls. The levels of serum IgG and cytokines (IFN-γ and IL-4) were determined by ELISA methods. Spleens of the chickens were separated for RNA-Seq analysis. Our results showed that immunization of IBD vaccine in HA induced significantly higher productions of IgG, IFN-γ and IL-4 than that in the nape. RNA-Seq analysis identified 444 differentially expressed genes (DEGs) and 3 canonical signaling pathways including ECM-receptor interaction, NOD-like and RIG-I like receptor signaling pathways in HA vs Control, which was different from that in Nape vs Control. Therefore, the different levels of the immune responses to IBD vaccine might be resulted from the activated molecules and pathways affected by the administration route. These findings might offer supports for the use of Houhai acupoint as an alternative administration route of vaccines in poultry.

Molecular mechanisms underlying macrophage immunomodulatory activity of Rubus chingii Hu polysaccharides

The present study was to investigate the mechanisms involved in macrophage activation by polysaccharides from the fruits of Rubus chingii Hu (RFPs). The results showed that RFPs enhanced pinocytic and phagocytic activity, promoted the expression and secretion of inflammatory factors (ROS, PTGS2, iNOS, IL-6, IL-10 and TNF-α) and chemokines (CCL2 and CXCL10), and boosted the expression of accessory and costimulatory molecules (CD40, CD80, CD86, MHC-I and MHC-II). RNA-Seq analysis identified 2564 DEGs, 1710 GO terms and 101 KEGG pathways. TNF was identified as the core gene via analysis of pathway information integration and PPI network. The western blot analysis combined with functional verification assay confirmed that MAPK, NF-κB and Jak-STAT pathways were essential to RFPs-mediated macrophage activation. TLR2 was revealed to be the functional receptor and involved in the early recognition of RFPs. These results indicated that RFPs modulated macrophage immune response mainly through TLR2-dependent MAPK, NF-κB and Jak-STAT pathways.

Atractylodis macrocephalae polysaccharides protect against DSS-induced intestinal injury through a novel lncRNA ITSN1-OT1

Many dietary polysaccharides have been shown to protect the intestinal barrier integrity against several noxious stimuli. Previously, we have isolated a polysaccharide RAMPtp from Atractylodis macrocephalae Koidz, and analyzed its structure. However, the effects of RAMPtp on intestinal barrier function have not been investigated. Here, we evaluated the protective effects of RAMPtp on Dextran sulfate sodium (DSS)-induced intestinal epithelial cells (IECs) injury. The findings showed that RAMPtp boosted the proliferation and survival of IECs during DSS stimulation. Furthermore, we found that RAMPtp protected the IECs from injury induced by DSS through maintaining the barrier function and inflammation response. Mechanistically, we identified a novel lncRNA ITSN1-OT1, which was induced by RAMPtp during DSS stimulation. It blocked the nuclear import of phosphorylated STAT2 to prevent the DSS induced decreased expression and structural destroy of tight junction proteins. Hence, the study clarified the protective effects and mechanism of polysaccharides RAMPtp on DSS-induced intestinal barrier dysfunction.

Sunflower seed oil combined with ginseng stem-leaf saponins as an adjuvant to enhance the immune response elicited by Newcastle disease vaccine in chickens

The present study was to evaluate the adjuvant effect of sunflower seed oil containing saponins extracted from the stem and leaf of Panax ginseng C.A. Meyer (E515-D) on the immune response induced by an inactivated Newcastle disease virus (NDV) in chickens. The results showed that E515-D promoted significantly higher serum NDV-specific HI and neutralizing antibody responses, IFN-γ and IL-4 levels, and lymphocyte proliferative responses to Con A, LPS, and NDV antigen than the conventional adjuvant Marcol 52. Different adjuvant effect between E515-D and Marcol 52 may be attributed to different genes expressed in two groups. Transcriptome analysis of splenocytes showed that there were 1198 differentially expressed genes (DEGs) with 539 up and 659 down regulated in E515-D group while 1395 DEGs with 697 up and 698 down regulated in Marcol 52 group in comparison with the control group. Analysis of gene ontology (GO) term and kyoto encyclopedia of Genes and Genomes (KEGG) pathways showed that the predominant immune related pathways included "Toll-like receptor signaling pathway", "NOD-like receptor signaling pathway", "C-type lectin receptor signaling pathway", and "Phosphatidylinositol signaling system" in E515-D group while Marcol 52 were "NOD-like receptor signaling pathway", "Phagosome", and "Lysosome", and the most relevant DEGs in E515-D group were STAT1, STAT2, PI3K, and IL-6. Considering the excellent adjuvant activity and vegetable origin, E515-D deserves further study as an adjuvant for vaccines used in food animals.

Immunomodulatory effect of ginseng stem-leaf saponins and selenium on Harderian gland in immunization of chickens to Newcastle disease vaccine

Our previous study demonstrated that ginseng stem-leaf saponins (GSLS) in combination with selenium (GSLS-Se) have adjuvant effect on the live vaccine of Newcastle disease virus (NDV) and infectious bronchitis virus (IBV) in intraocular-and-intranasal immunization in chickens. The present study was to investigate the potential molecular mechanisms involved in the immunomodulation of GSLS-Se on the Harderian gland (HG). It was found that the window allowing animals susceptible to infections due to low antibody titers became smaller or even completely closed because of increased NDV-specific HI titers when NDV vaccine and GSLS-Se were coadministered for immunization at early life in chickens. In addition, NDV-specific sIgA and the numbers of IgG+, IgA+, IgM+ plasma cells were significantly more in GSLS-Se group than the control in the HGs. Transcriptome analysis of HGs identified 1184 differentially expressed genes (DEGs) between GSLS-Se treated and non-treated groups. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses identified 42 significantly enriched GO terms and 13 canonical immune pathways. These findings indicated that GSLS-Se might exert immunomodulatory effects through influencing the antioxidant regulation and modulating the activity of immune related enzymes. Besides, Toll-like receptor (TLR) signaling pathway and mitogen-activated protein kinase (MAPK) signaling pathway might be involved primarily in the immunomodulation. Therefore, enhanced antibody responses in GSLS-Se group may be attributed to the immunomodulatory effects of GSLS-Se on the immune-related gene profile expressed in the immunocompetent cells of the HGs.

Receptor and signaling pathway involved in bovine lymphocyte activation by Atractylodis macrocephalae polysaccharides

The present study was to investigate the molecular mechanism underlying lymphocyte activation by total polysaccharides from Atractylodis macrocephalae (RAMPtp). The results showed that RAMPtp significantly promoted the secretions of cytokines (IFN-γ, IL-1α, IL-21, IFN-α, CCL4, CXCL9 and CXCL10), increased the proportions of CD4⁺ and CD8⁺ subpopulations, and enhanced the expressions of c-JUN, NFAT4, STAT1 and STAT3. microRNA sequencing identified 67 differentially expressed miRNAs (DEMs) in RAMPtp-stimulated SMLN lymphocytes, including 55 up-regulated and 12 down-regulated. GO and KEGG enrichment analyses of the predicted DEMs-targeted genes indicated that they were associated with immune system pathways, including PI3K-Akt, MAPKs, Jak-STAT and Calcium signaling pathways, which were confirmed by western blot and pathway inhibition assays. RAMPtp was further observed to favor immunostimulatory effect on both T and B lymphocytes via binding to TCR and membrane Ig individually. These findings might explain the immunomodulatory mechanism of RAMPtp in ameliorating the bovine intramammary infection.

Molecular mechanisms associated with macrophage activation by Rhizoma Atractylodis Macrocephalae polysaccharides

The present study was to elucidate the mechanisms underlying macrophage activation by total polysaccharides from Rhizoma Atractylodis Macrocephalae (RAMPtp). The results showed that RAMPtp significantly promoted productions of NO, ROS, cytokines and chemokines, enhanced pinocytic and phagocytic activity, and upregulated expressions of accessory and costimulatory molecules. RNA-seq analysis presented 2868 DEGs and 737 GO terms. PPI network analysis in combination with KEGG pathways as well as the western blot and functional verification assays indicated that NF-κB and STATs were the key regulators modulating the expressions of core gene TNF-α and IL-6 individually, and the transposition activation of NF-κB was identified as an early event in macrophage activation induced by RAMPtp. The involvements of MAPKs and PI3K-Akt pathways were also determined. These results indicated that immune response and immune function were regulated in RAMPtp-stimulated macrophages via a complex interaction network, in which NF-κB and Jak-STAT signaling pathways played a pivotal role.

Early IgG Response to Foot and Mouth Disease Vaccine Formulated with a Vegetable Oil Adjuvant

The present study evaluated soybean oil (SO) containing vitamin E (VE) and ginseng saponins (GS) (SO-VE-GS) for their adjuvant effect on foot-and-mouth disease (FMD) vaccine. Since mineral oil ISA 206 is a common adjuvant used in the FMD vaccine, it was used as a control adjuvant in this study. VE and GS were found to have a synergistic adjuvant effect. When mice were immunized with the FMD vaccine emulsified in SO with VE and GS, significantly higher serum IgG, IgG1, and IgG2a were found than VE and GS used alone. SO-VE-GS and ISA 206 behaved differently in adjuvant activities. When mice were immunized with the FMD vaccine adjuvanted with SO-VE-GS, significantly higher and earlier production of serum IgG was found than that adjuvanted with ISA 206. Although both adjuvants significantly increased the number of bone marrow plasma cells, a stimulation index of lymphocytes (SI) as well as the production of IL-4 and IL-6, SO-VE-GS promoted significantly higher SI and the ratio of CD4⁺/CD8⁺ T cells with production of increased IFN-γ and decreased TGF-β1 as compared with the ISA 206 group. The data suggested that SO-VE-GS activated Th1/Th2 immune responses. Transcriptome analysis of splenocytes showed that differentially expressed genes (DEGs), immune-related gene ontology (GO) terms, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were significantly enriched in the SO-VE-GS group. Therefore, the potent adjuvant effect of SO-VE-GS on the FMD vaccine may be attributed to the immune-related gene profile expressed in lymphocytes. Due to its plant origin and due to being much cheaper than imported mineral oil ISA 206, SO-VE-GS deserves further study in relation to vaccines used in food animals.

Immunomodulatory effect of thymopentin on lymphocytes from supramammary lymph nodes of dairy cows

Previous study showed that injection of thymopentin (TP 5) in the area of supramammary lymph nodes (SMLN) had therapeutic effect on the intramammary infection (IMI) in cows. This study was to explore the underlying mechanisms by investigating the immunomodulatory effect of TP 5 on SMLN lymphocytes. Lymphocyte proliferation, cell cycle distribution and cytokine mRNA expression were determined by MTT, FCM and RT-qPCR, respectively. Laser scanning confocal microscope (LSCM) was used to observe the binding between TP 5 and SMLN lymphocytes. Moreover, RNA-sequencing (RNA-seq) was performed to observe the difference between the lymphocytes with and without TP 5 treatment. The results showed that TP 5 significantly promoted lymphocyte proliferation, accelerated cell cycle progression, and enhanced mRNA expression of IL-17A and IL-17F. Laser scanning confocal microscopic analysis revealed the binding of TP 5 to the surface of SMLN lymphocytes. A total of 1094 genes were identified as differentially expressed genes (DEGs) using RNA-seq with 692 up- and 402 down-regulated genes. 48 significantly enriched GO terms were identified by RNA-seq. In KEGG analysis, 1/3 of DEGs were enriched in the immune system pathway, including IL-17 signaling pathway, cytokine-cytokine receptor interaction, Th1 and Th2 cell differentiation, T cell receptor signaling pathway, Th17 cell differentiation. Among them, IL-17 signaling pathway was the most prominent. This study suggested that the therapeutic benefit of TP 5 in the treatment of bovine mastitis might be attributed to its immunomodulatory activity in SMLN lymphocytes.

Protective Effect of Ginsenoside Rg1 on Oxidative Damage Induced by Hydrogen Peroxide in Chicken Splenic Lymphocytes

Previous investigation showed that ginsenoside Rg1 (Rg1) extracted from Panax ginseng C.A. Mey has antioxidative effect on oxidative stress in chickens. The present study was designed to investigate the protective effects of Rg1 on chicken lymphocytes against hydrogen peroxide-induced oxidative stress and the potential mechanisms. Cell viability, apoptotic cells, malondialdehyde, activity of superoxide dismutase, mitochondrial membrane potential, and [Ca²⁺]i concentration were measured, and transcriptome analysis and quantitative real-time polymerase chain reaction were used to investigate the effect of Rg1 on gene expression of the cells. The results showed that treatment of lymphocytes with H₂O₂ induced oxidative stress and apoptosis. However, pretreatment of the cells with Rg1 dramatically enhanced cell viability, reduced apoptotic cells, and decreased oxidative stress induced by H₂O₂. In addition, Rg1 reduced these H₂O₂-dependent decreases in mitochondrial membrane potential and reversed [Ca²⁺]i overload. Transcriptome analysis showed that 323 genes were downregulated and 105 genes were upregulated in Rg1-treated cells. The differentially expressed genes were involved in Toll-like receptors, peroxisome proliferator-activated receptor signaling pathway, and cytokine-cytokine receptor interaction. The present study indicated that Rg1 may act as an antioxidative agent to protect cell damage caused by oxidative stress via regulating expression of genes such as RELT, EDA2R, and TLR4.

Signaling pathway underlying splenocytes activation by polysaccharides from Atractylodis macrocephalae Koidz

Previous study demonstrated that total polysaccharides isolated from Atractylodis macrocephalae Koidz. (RAMPtp) were effective to eliminate intramammary infection in cows. The present study was designed to investigate the immunomodulatory activity of RAMPtp in mouse splenocytes. Splenocyte proliferation, natural killer (NK) cytotoxicity, productions of NO and cytokines, transcription factor activity as well as the signal pathways and receptor were examined. The results showed that RAMPtp significantly promoted splenocyte proliferation and made the cells enter S and G2/M phases, increased ratios of T/B cells, boosted NK cytotoxicity, enhanced transcriptional activities of nuclear factor of activated T cells (NFAT), nuclear factor κB (NF-κB) and activator protein 1 (AP-1), and stimulated secretions of NO, immunoglobulin G (IgG) and multiple cytokine families (IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-6, IL-10, IL-12p40, IL-12p70, IL-13, IFN-γ, TNF-α, G-CSF, GM-CSF, KC, MIP-1α, MIP-1β, RANTES and Eotaxin). In addition, all the specific inhibitors against the mitogen-activated protein kinases (MAPKs) and NF-κB significantly suppressed the IL-6 production induced by RAMPtp. Moreover, splenocytes from Toll-like receptor 4 (TLR4) deficient mouse responded equally to RAMPtp stimulation as the wild-type. Therefore, RAMPtp might induce splenocytes activation at least in part via the TLR4-independent MAPKs and NF-κB signaling pathways. The present results would be useful to further understand the immunomodulatory mechanisms of RAMPtp in elimination of intramammary infection in cows.