Based on previous studies about microflora regulation and immunity enhancement activities of polysaccharides from
Nannf. var.
(Nannf.) L. T. Shen (CPP), there is little study on intestinal mucosal ...immunity, which is a possible medium for contacting microflora and immunity. In the present study, the BALB/c mice were divided into five groups (eight mice in each group), including a normal group (Con), a model control group (Model), and model groups that were administered CPP (50, 100, 200 mg/kg/d) orally each day for seven days after intraperitoneal injection of 60 mg/kg BW/d cyclophosphamide (CP) for three days. CPP recovered the spleen index and restored the levels of IFN-γ, IL-2, IL-10, as well as serum IgG. In addition, it elevated ileum secretory immunoglobulin A (sIgA), the number of
and acetic acid content in cecum. These results indicated that CPP plays an important role in the protection against immunosuppression, especially mucosa immune damage, and the inhibition of pathogenic bacteria colonization, which could be considered a potential natural source of immunoregulator.
In this study, an acidic polysaccharide from
Nannf. var.
(Nannf.) L. T. Shen (WCP-I) and its main fragment, WCP-Ia, obtained after pectinase digestion, were structurally elucidated and found to ...consist of a rhamnogalacturonan I (RG-I) region containing both arabinogalactan type I (AG-I) and type II (AG-II) as sidechains. They both expressed immunomodulating activity against Peyer's patch cells. Endo-1,4-β-galactanase degradation gave a decrease of interleukine 6 (IL-6) production compared with native WCP-I and WCP-Ia, but exo-α-l-arabinofuranosidase digestion showed no changes in activity. This demonstrated that the stimulation activity partly disappeared with removal of β-d-(1→4)-galactan chains, proving that the AG-I side chain plays an important role in immunoregulation activity. WCP-Ia had a better promotion effect than WCP-I in vivo, shown through an increased spleen index, higher concentrations of IL-6, transforming growth factor-β (TGF-β), and tumor necrosis factor-α (TNF-α) in serum, and a slight increment in the secretory immunoglobulin A (sIgA) and CD4
/CD8
T lymphocyte ratio. These results suggest that β-d-(1→4)-galactan-containing chains in WCP-I play an essential role in the expression of immunomodulating activity. Combining all the results in this and previous studies, the intestinal immune system might be the target site of WCP-Ia.
is a plant widely used in traditional Chinese medicine, of which polysaccharides are reported to be the main components responsible for its bio-functions. In this work, the inulin-type fructan (PGF) ...was obtained by DEAE anion exchange chromatography from the water extracted from
. Characterization was performed with methanolysis, methylation, and NMR and the results showed that PGF is a β-(2-1) linked fructan, with terminal glucose and with a degree of polymerization of 2⁻10. In order to study its biofunctions, the prebiotic and immunomodulation properties were assayed. We found that PGF exhibited good prebiotic activity, as shown by a promotion on six strains of lactobacillus proliferation. Additionally, the PGF also displayed direct immunomodulation on intestinal epithelial cells and stimulated the expressions of anti-inflammatory factors. These results indicated that the inulin from
is a potential natural source of prebiotics as well as a potential intestinal immunomodulator, which will be valuable for further studies and new applications.
Flaviviridae family is a class of single-stranded RNA virus, which is fatal to human and animals and mainly prevalent in subtropic and tropic countries. Even though people and animals are barraged ...with flavivirus infection every year, we have not invented either vaccines or antiviral for most flavivirus infections yet. Innate immunity is the first line of defense in resisting pathogen invasion, serving an important role in a resisting virus. Toll-like receptors (TLRs) and retinoic acid-inducible gene I- (RIG-I-) like receptors (RLRs) are crucial pattern recognition receptors (PRRs) that play essential roles in recognizing and clearing pathogens, including resisting flavivirus. In the present review, we provide a significant reference for further research on the function of innate immunity in resisting flavivirus.
In this study, the
leaf polysaccharide (NNLP) was isolated by hot water extraction and ethanol precipitation. DEAE anion exchange chromatography and gel filtration were further performed to obtained ...the purified fraction NNLP-I-I, the molecular weight of which was 16.4 kDa. The monosaccharide composition analysis and linkage units determination showed that the fraction NNLP-I-I was a pectic polysaccharide. In addition, the NMR spectra analysis revealed that NNLP-I-I mainly consisted of a homogalacturonan backbone and rhamnogalacturonan I, containing a long HG region and short RG-I region, with AG-II and 1-3 linked rhamnose as side chains. The biological studies demonstrated that NNLP-I-I displayed antioxidant properties through mediating the Nrf2-regulated intestinal cellular antioxidant defense, which could protect cultured intestinal cells from oxidative stress and improve the intestinal function of aged mice.
Exosomes are small membrane vesicles that retain various substances such as proteins, nucleic acids, and small RNAs. Exosomes play crucial roles in many physiological and pathological processes, ...including innate immunity. Innate immunity is an important process that protects the organism through activating pattern recognition receptors (PRRs), which then can induce inflammatory factors to resist pathogen invasion. Toll-like receptor (TLR) is one member of PRRs and is important in pathogen clearance and nervous disease development. Although exosomes and TLRs are two independent materials, abundant evidences imply exosomes can regulate innate immunity through integrating with TLRs. Herein, we review the most recent data regarding exosome regulation of TLR pathways. Specifically, exosome-containing materials can regulate TLR pathways through the interaction with TLRs. This is a new strategy regulating immunity to resist pathogens and therapy diseases, which provide a potential method to cure diseases.
Pseudorabies virus (PRV), in the family Herpesviridae, is a pathogen of Aujeszky's disease, which causes great economic losses to the pig industry. Recent outbreaks of Pseudorabies imply that new ...control measures are urgently needed. The present study shows that kaempferol is a candidate drug for controlling PRV infection, as it possesses the ability to inhibit PRV replication in a dose-dependent manner in vitro. Kaempferol at a concentration of 52.40 µmol L−1 could decrease PRV-induced cell death by 90%. With an 50% inhibitory concentration (IC50) value of 25.57 µmol L−1 kaempferol was more effective than acyclovir (positive control) which has an IC50 value of 54.97 µmol L−1. A mode of action study indicated that kaempferol inhibited viral penetration and replication stages, decreasing viral loads by 4- and 30-fold, respectively. Addition of kaempferol within 16 h post infection (hpi) could significantly inhibit virus replication, and viral genome copies were decreased by almost 15-fold when kaempferol was added at 2 hpi. Kaempferol regulated the NF-κB and MAPKs signaling pathways involved in PRV infection and changed the levels of the target genes of the MAPKs (ATF-2 and c-Jun) and NF-κB (IL-1α, IL-1β and IL-2) signaling pathways. The findings of the current study suggest that kaempferol could be an alternative measure to control PRV infection.
An inulin (CPPF), isolated from a traditional Chinese herbal medicine
, was characterized and demonstrated with potential prebiotic activity
before. Based on its non-digested feature, the intestinal ...mucosa and microbiota modulatory effects
on immunosuppressed mice were investigated after oral administration of 200, 100 and 50 mg/kg of CPPF for 7 days. It was demonstrated that the secretions of sIgA and mucin 2 (Muc2) in ileum were improved by CPPF, and the anti-inflammatory activities in different intestine parts were revealed. The intestine before colon could be the target active position of CPPF. As a potential prebiotic substance, a gut microbiota restorative effect was also presented by mainly modulating the relative abundance of
, including
,
and Lachnospiraceae after high-throughput pyrosequencing of V4 region of 16S rRNA analysis. All these results indicated that this main bioactive ingredient inulin from
was a medicinal prebiotic with enhancing mucosal immune, anti-inflammatory and microbiota modulatory activities.