Silencing of tropomodulin 1 inhibits acute myeloid leukemia cell proliferation and tumor growth by elevating karyopherin alpha 2-mediated autophagy.

Evidence shows that tropomodulin 1 (TMOD1) is a powerful diagnostic marker in the progression of several cancer types. However, the regulatory mechanism of TMOD1 in tumor progression is still unclear. Here, we showed that TMOD1 was highly expressed in acute myeloid leukemia (AML) specimens, and TMOD1-silencing inhibited cell proliferation by inducing autophagy in AML THP-1 and MOLM-13 cells. Mechanistically, the C-terminal region of TMOD1 directly bound to KPNA2, and TMOD1-overexpression promoted KPNA2 ubiquitylation and reduced KPNA2 levels. In contrast, TMOD1-silencing increased KPNA2 levels and facilitated the nuclear transfer of KPNA2, then subsequently induced autophagy and inhibited cell proliferation by increasing the nucleocytoplasmic transport of p53 and AMPK activation. KPNA2/p53 inhibitors attenuated autophagy induced by silencing TMOD1 in AML cells. Silencing TMOD1 also inhibited tumor growth by elevating KPNA2-mediated autophagy in nude mice bearing MOLM-13 xenografts. Collectively, our data demonstrated that TMOD1 could be a novel therapeutic target for AML treatment.

A novel polysaccharide isolated from Coriolus versicolor polarizes M2 macrophages into an M1 phenotype and reversesits immunosuppressive effect on tumor microenvironment.

Converting M2 macrophages into an M1 phenotype in the tumor microenvironment, provides a new direction for tumor treatment. Here, we further report CVPW-1, a new polysaccharide of 1.03 × 106 Da that was isolated from Coriolus versicolor. Its monosaccharide was composed of mannose, glucose, and galactose at a ratio of 1.00:8.73:1.68. The backbone of CVPW-1 was composed of (1 â†’ 3)-linked α-D-Glcp residues and (1 â†’ 3,6)-linked α-D-Glcp residues that branched at O-6. The branch consisted of (1 â†’ 6)-linked α-D-Glcp residues and (1 â†’ 4)-linked α-D-Glap, and some branches were terminated with (1→)-linked ß-D-Manp residues according to the results of HPLC, FT-IR, GC-MS, 1D and 2D NMR. Meanwhile, CVPW-1 could polarize M2 macrophages to M1 phenotypein vitro by binding to TLR4 and inducing the activation of Akt, JNK and NF-κB. This process involved reversing the functional inhibition of CD8+ T lymphocytes by inhibiting the expression of TREM2 in M2 macrophages. The in vivo experiments showed that oral administration of CVPW-1 could inhibit the growth of tumor in mice and polarize TAMs to M1 phenotype. Thus, the novel polysaccharide CVPW-1 from Coriolus versicolor might activate a variety of immune cells and then play an anti-tumor role. These results demonstrated that CVPW-1 could be developed as a potential immuno-oncology treatment reagent.

Characterization of a novel polysaccharide from Arca subcrenata and its immunoregulatory activities in vitro and in vivo.

Arca subcrenata is an economical edible shellfish. A novel water-soluble α-D-glucan (ASPG-1) with a molecular weight of 2.56 × 106 Da was purified and characterized from A. subcrenata. Its structure was characterized as a repeating unit consisting of α-D-Glcp, (1 → 6)-α-D-Glcp and (1 → 4,6)-α-D-Glcp. ASPG-1 exerted potent immunoregulatory activity by promoting the viability of splenic lymphocytes. Moreover, it enhanced pinocytic capacity, and promoted the secretion of NO and cytokines in RAW264.7 cells. The immunomodulatory mechanism of ASPG-1 involved the activation of the TLR4-MAPK/Akt-NF-κB signaling pathway. ASPG-1 inhibited tumor growth in 4T1 breast cancer mice and its combination with doxorubicin increased antitumor efficacy. The ASPG-1 combination with DOX-treated group (64.8%) showed an improved tumor inhibition rate compared to that of the DOX-treated group (53.3%). The antitumor mechanism of ASPG-1 may involve an enhancement of the immune response of mice to tumors. These results indicated that ASPG-1 could be developed as a potential adjuvant in tumor immunotherapy.

A new GlcNAc-containing polysaccharide from Morchella importuna fruiting bodies: Structural characterization and immunomodulatory activities in vitro and in vivo.

This study investigated the purification and characterization of a new immunomodulatory GlcNAc-containing polysaccharide (MIPB70-1) from Morchella importuna with molecular weights of 20.6 kDa. Structural analysis indicated that MIPB70-1 was composed of GlcNAc:Gal:Glc:Man with molar ratios of 1.00:7.16:5.54:5.61, and its primary structure was characterized as a repeating unit consisting of →6)-α-D-Glcp-(1→, α-D-GlcpNAc-(1→, α-D-Galp-(1→, ß-D-Glcp-(1→, →6)-α-D-Manp-(1→, →4)-α-D-GlcpNAc-(1→, →4)-ß-D-Glcp-(1→, →3,6)-α-D-Manp-(1→, →2)-α-D-Galp-(1→, →2,3,6)-α-D-Manp-(1→. Immunological assays indicated that MIPB70-1 enhanced the phagocytic function and promoted the secretion of nitric oxide (NO) as well as cytokines through targeting Toll-like receptor 4 (TLR4) on macrophage membrane and activating the downstream signaling pathways in RAW 264.7 cells. MIPB70-1 regulated mouse immunity to counteract the immune damage caused by the chemotherapy drug cyclophosphamide (CTX) in vivo. Furthermore, MIPB70-1 enhanced the anti-tumor activity of doxorubicin (DOX) and inhibited the growth of tumors, by immunomodulation in the orthotopic murine model of 4T1 breast cancer. These results demonstrate the potential of this GlcNAc-containing polysaccharide as an immune enhancer.

Purification and characterization of a novel mixed-linkage α,ß-d-glucan from Arca subcrenata and its immunoregulatory activity.

Arca subcrenata Lischke is a seafood with high nutritional value. In this study, we purified and characterized a novel water-soluble polysaccharide (ASPG-2) from Arca subcrenata with significant immunoregulatory effects and no apparent cell toxicity. ASPG-2 is a class of mixed-linkage α,ß-d-glucan backbones with α-linked side chains with a molecular weight of 4.39 × 105 Da. Its structure was characterized as a repeating unit consisting of (1 → 3)-ß-d-Glcp, (1 → 4)-α-d-Glcp, (1 → 4,6)-α-d-Glcp and (1 → 6)-α-d-Glcp. Using mouse RAW264.7 macrophages, we demonstrated that ASPG-2 exerted marked immunoregulatory effects by promoting the secretion of NO and increasing the phagocytosis of RAW264.7 cells in vitro. Moreover, flow cytometry analysis of the expression of the cell surface molecule CD86 revealed that ASPG-2 could polarize RAW264.7 cells into the M1 type. The immunomodulatory mechanism of ASPG-2 in macrophages was associated with the activation of the TLR4-MAPK/Akt-NF-κB signalling pathways. These results indicated that ASPG-2 might be researched and developed as a potential immunomodulatory agent or health product from marine organisms.

Structural characterization and immunomodulatory mechanisms of two novel glucans from Morchella importuna fruiting bodies.

Two novel glucans named MIPB50-W and MIPB50-S-1 were obtained from edible Morchella importuna with molecular weights (Mw) of 939.2 kDa and 444.5 kDa, respectively. MIPB50-W has a backbone of α-(1 → 4)-d-glucan, which was substituted at O-6 position by α-d-Glcp-(1→. Moreover, MIPB50-S-1 has a backbone of α-(1 → 4)-d-glucan, which was substituted at O-6 position by α-d-Glcp-(1 → 6)-α-d-Glcp-(1→. This is the first report about glucan found in Morchella mushrooms. Furthermore, MIPB50-W and MIPB50-S-1 strengthened the phagocytosis function and the promoted secretion of interleukins (IL)-6/tumor necrosis factor-alpha (TNF-α) and nitric oxide (NO), which induced the activation of Toll-like receptor 2 (TLR2), TLR4 as well as mitogen activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways. Interestingly, MIPB50-S-1 performed the better immunomodulatory activity than that of MIPB50-W in almost all tests. Therefore, MIPB50-W and MIPB50-S-1 are potential immune-enhancing components of functional foods.

Purification and Characterization of a New CRISP-Related Protein from Scapharca broughtonii and Its Immunomodulatory Activity.

More and more attention has been paid to bioactive compounds isolated from marine organisms or microorganisms in recent years. At the present study, a new protein coded as HPCG2, was purified from Scapharca broughtonii by stepwise chromatography methods. The molecular weight of HPCG2 was determined to be 30.71 kDa by MALDI-TOF-MS. The complete amino acid sequence of HPCG2 was obtained by tandem mass spectrometry combined with transcriptome database analysis, and its secondary structure was analyzed using circular dichroism. HPCG2 comprised 251 amino acids and contained 28.4% α-helix, 26% ß-sheet, 18.6% ß-turn, and 29.9% random coil. HPCG2 was predicted to be a cysteine-rich secretory protein-related (CRISP-related) protein by domain prediction. Moreover, HPCG2 was proved to possess the immunomodulatory effect on the murine immune cells. MTT assay showed that HPCG2 promoted the proliferation of splenic lymphocytes and the cytotoxicity of NK cells against YAC-1 cells. Flow cytometry test revealed that HPCG2 enhanced the phagocytic function of macrophages and polarized them into M1 type in RAW264.7 cells. In particular, Western blot analysis indicated that the immunomodulatory mechanism of HPCG2 was associated with the regulation on TLR4/JNK/ERK and STAT3 signaling pathways in RAW 264.7 cells. These results suggested that HPCG2 might be developed as a potential immunomodulatory agent or new functional product from marine organisms.

The ß-catenin/TCF-4-LINC01278-miR-1258-Smad2/3 axis promotes hepatocellular carcinoma metastasis.

Hepatocellular carcinoma (HCC) metastasis is largely responsible for HCC-associated recurrence and mortality. We aimed to identify metastasis-related long non-coding RNAs (lncRNAs) to understand the molecular mechanism of HCC metastasis. We first identified that miR-1258 was downregulated in HCC tissues both in The Cancer Genome Atlas (TCGA) and Sun Yat-sen University Cancer Center (SYSUCC) dataset. MiR-1258 expression negatively correlated with recurrence-free survival and overall survival of HCC patients. MiR-1258 overexpression inhibited migration and invasion of HCC cells both in vitro and in vivo, whereas miR-1258 downregulation promoted cell metastasis. Luciferase assays verified direct binding of miR-1258 to Smad2 and Smad3, thereby attenuating TGF-ß/Smad signaling. We further established that lncRNA LINC01278 was a negative regulator of miR-1258. In vivo and in vitro assays demonstrated that LINC01278-mediated HCC metastasis was dependent on miR-1258 expression. Furthermore, miR-1258 downregulation in turn increased LINC01278 expression. We also observed that TCF-4 could bind to the LINC01278 promoter site. In addition, LINC01278 downregulation decreased migration and invasion of HCC cells induced by ß-catenin and TGF-ß1 both in vitro and in vivo. We uncovered a novel mechanism for ß-catenin/TCF-4-LINC01278-miR-1258-Smad2/3 feedback loop activation in HCC metastasis, and the study indicated that LINC01278 could serve as a therapeutic target for HCC metastasis.

Structural characterization and biological activities of a novel polysaccharide containing N-acetylglucosamine from Ganoderma sinense.

A novel homogeneous heteropolysaccharide (GSPB70-S) with a molecular weight of 2.87 kDa was isolated from Ganoderma sinense. Structural analysis showed that GSPB70-S was composed of glucose, glucosamine, mannose, and galactose with a molar ratio of 12.90:3.70:2.26:1.00. The repeating structure units of GSPB70-S were characterized by the combined application of chemical methods and nuclear magnetic resonance. GSPB70-S contains a backbone of →3)-ß-D-Glcp-(1 → 4)-α-D-GlcpNAc-(1 → 4)-α-D-Manp-(1 → 3)-ß-D-Glcp-(1→, with branches of ß-D-Glcp-(1→, α-D-GlcpNAc-(1 → and →4)-α-D-Galp-(1→. Scanning electron microscope (SEM) showed that GSPB70-S presented a long strip shape with different thicknesses, and there were many lamellar substances on the surface. Biological research showed that GSPB70-S inhibited the activity of α-glucosidase in vitro, increased the viability of RAW 264.7 macrophages, and promoted the release of NO. In addition, GSPB70-S showed good abilities to scavenge free radicals.

Cordyceps militaris polysaccharide converts immunosuppressive macrophages into M1-like phenotype and activates T lymphocytes by inhibiting the PD-L1/PD-1 axis between TAMs and T lymphocytes.

Tumour-associated macrophages (TAMs) inhibit the killing effect of T lymphocytes on tumour cells through the immunocheckpoint programmed death ligand-1 (PD-L1)/programmed death-1 (PD-1) axis. TAMs-targeted therapy is a promising approach that could be used to reverse the immunosuppressive tumour microenvironment. Here, we further report CMPB90-1, a novel natural polysaccharide from Cordyceps militaris, could function as an anti-tumour modulator that resets TAMs from a tumour-promoting M2 phenotype to a tumour-killing M1 phenotype. This process involves reversing the functional inhibition of T lymphocytes by inhibiting the PD-L1/PD-1 axis between TAMs and T lymphocytes. Mechanistically, the membrane receptor of CMPB90-1 binding to M2 macrophages was identified by tandem mass spectrometry. CMPB90-1 converts immunosuppressive TAMs via binding to toll-like receptor 2 (TLR2), which causes the release of Ca2+ and the activation of p38, Akt and NF-κB, or ERK. This process then leads to the polarization of TAMs from M2 phenotype to the M1 phenotype. In vivo experiment shows that CMPB90-1 is able to polarize TAMs into the M1 phenotype and has anti-tumour effects with improved safety. Additionally, the anti-tumour effects of CMPB90-1 in vivo depend on the phenotypic conversion of TAMs. The results demonstrated that CMPB90-1 could be developed as a potential immune-oncology treatment reagent.

Identification and Characterization of a Novel Protein ASP-3 Purified from Arca subcrenata and Its Antitumor Mechanism.

Diverse bioactive substances derived from marine organisms have been attracting growing attention. Besides small molecules and polypeptides, numerous studies have shown that marine proteins also exhibit antitumor activities. Small anticancer proteins can be expressed in vivo by viral vectors to exert local and long-term anticancer effects. Herein, we purified and characterized a novel protein (ASP-3) with unique antitumor activity from Arca subcrenata Lischke. The ASP-3 contains 179 amino acids with a molecular weight of 20.6 kDa. The spectral characterization of ASP-3 was elucidated using Fourier Transform infrared spectroscopy (FTIR) and Circular Dichroism (CD) spectroscopy. Being identified as a sarcoplasmic calcium-binding protein, ASP-3 exhibited strong inhibitory effects on the proliferation of Human hepatocellular carcinoma (HepG2) cells with an IC50 value of 171.18 ± 18.59 µg/mL, measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The RNA-seq analysis showed that ASP-3 regulated the vascular endothelial growth factor receptor (VEGFR) signaling pathway in HepG2 cells. Immunofluorescence results indicated that ASP-3 effectively reduced VEGFR2 phosphorylation in HepG2 cells and affected the downstream components of VEGF signaling pathways. The surface plasmon resonance (SPR) analysis further demonstrated that ASP-3 direct interacted with VEGFR2. More importantly, the therapeutic potential of ASP-3 as an anti-angiogenesis agent was further confirmed by an in vitro model using VEGF-induced tube formation assay of human umbilical vein endothelial cells (HUVECs), as well as an in vivo model using transgenic zebrafish model. Taken together, the ASP-3 provides a good framework for the development of even more potent anticancer proteins and provides important weapon for cancer treatment using novel approaches such as gene therapy.

A new polysaccharide isolated from Morchella importuna fruiting bodies and its immunoregulatory mechanism.

A new polysaccharide (MIPW50-1) with a molecular weight of 28.5 kDa was isolated from Morchella importuna fruiting bodies. Structural analysis indicated that MIPW50-1 was composed of N-acetylglucosamine, galactose, glucose, and mannose with molar ratios of 1.00:14.95:1.53:10.51, and its structure was characterized as a repeating unit consisting of →2,3,6)-α-D-Manp-(1→, →3,6)-α-D-Manp-(1→, →2)-α-D-Galp-(1→, →6)-α-D-Manp-(1→, →4)-ß-D-Glcp-(1→, →4)-α-D-GlcpNAc-(1→, →6)-α-D-Glcp-(1→, α-D-Galp-(1→, α-D-GlcpNAc-(1→ and ß-D-Glcp-(1→. The immunoregulatory effect of MIPW50-1 was also evaluated. MIPW50-1 was capable of stimulating macrophage function, rising phagocytosis of RAW264.7 cells as well as promoting secretion of NO, TNF-α and IL-6. Moreover, the immunoblot and ELISA assays demonstrated that MIPW50-1 exerted immune-potentiating effect through the TLR4/JNK and Akt/NF-κB signalling pathways in RAW264.7 cells. This is the first polysaccharide containing N-acetylglucosamine isolated from Morchella mushrooms, and MIPW50-1 might be used as one of potential immunoenhancing components in functional foods.

Structural characterization and immunoregulatory activity of a new polysaccharide from Citrus medica L. var. sarcodactylis.

A new homogeneous heteropolysaccharide (CMSPA90-1) was purified from bergamot by DEAE sepharose fast flow and Sephadex G-75 columns, and was shown to have a molecular weight of 17.6 kDa. Its chemical structure was elucidated by acid hydrolysis and methylation analysis, along with high-performance anion-exchange chromatography, Fourier transform infrared spectroscopy coupled with gas chromatography-mass spectrometry, NMR spectroscopies, the Congo red test, and circular dichroism. CMSPA90-1 consisted of a pyranoside and funanside with branches containing α- and ß-configurations simultaneously. Arabinose and glucose might form an arabinoglucan backbone. The ultrastructure of CMSPA90-1 was further characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The results of thermogravimetric analysis (TGA) revealed that CMSPA90-1 had good thermal stability. The results of DPPH˙ and ABTS+˙ radical scavenging assays indicated that CMSPA90-1 exhibited free-radical-scavenging properties. Otherwise, CMSPA90-1 could promote the proliferation of mouse splenocytes and the neutral red phagocytosis of RAW264.7 cells, which indicated that CMSPA90-1 could be researched and developed as one of the potential functional foods or natural medicines.

Cordyceps militaris fraction inhibits the invasion and metastasis of lung cancer cells through the protein kinase B/glycogen synthase kinase 3ß/ß-catenin signaling pathway.

Cordyceps militaris is widely used as a traditional Chinese medicine health supplement, and is also used in the development of anticancer agents. In our previous studies, it was revealed that C. militaris fraction (CMF) possessed an antitumor effect against K562 cells in vitro, induced apoptosis and caused cell cycle arrest in the S phase. The published results also demonstrated that CMF-induced apoptosis was involved in mitochondrial dysfunction. The aim of the present study was to investigate the anti-invasion and anti-metastasis effects of CMF in NCI-H1299 and Lewis lung cancer (LLC) cell lines, which have high metastatic potential. MTT and clone formation assays were initially used to investigate the inhibitory effect of CMF on the viability of NCI-H1299 and LLC cells. The results of cell adhesion, wound healing, migration and Matrigel invasion assays in vitro indicated that NCI-H1299 cells (treated with 1, 3, 10 or 30 µg/ml CMF) and LLC cells (treated with 0.1, 0.3, 1 or 3 µg/ml CMF) demonstrated a concentration-dependent reduction in cell migration and invasion compared with the control. In vivo experiments demonstrated that the oral administration of CMF (65, 130 or 260 mg/kg) decreased the tumor growth and decreased the lung and liver metastasis in an LLC xenograft model, compared with untreated mice. Furthermore, western blot analysis was used to investigate the mechanism of the effect of CMF on the migration of NCI-H1299 cells and metastasis in the xenograft model. The results revealed that CMF may promote glycogen synthase kinase 3ß (GSK-3ß)-mediated degradation of ß-catenin inhibited the phosphorylation of upstream protein kinase B (Akt), which resulted in the attenuation of the expression of matrix metalloproteinase (MMP)-2 and MMP-9. These results suggested that CMF may possess potential for the treatment of lung cancer metastasis via the Akt/GSK-3ß/ß-catenin pathway.

Structural characterization and immunomodulatory activity of a novel polysaccharide from Ficus carica.

A novel polysaccharide (FCPW80-2) with a molecular weight of 1.21 × 105 Da was first isolated from Ficus carica through hot water extraction and several chromatographic methods. The structure of FCPW80-2 was determined by chemical and instrumental analysis. The results showed that the backbone of FCPW80-2 consists of (1→5)-linked α-l-Ara, (1→3,6)-linked ß-d-Man and (1→4,6)-linked ß-d-Gal. The branches of FCPW80-2 consist of (1→4)-linked α-d-Glc and (1→3)-linked ß-l-Rha terminated with (1→)-linked ß-d-Glc. In vitro immunomodulatory activity assays revealed that FCPW80-2 could markedly promote the secretion of cytotoxic molecules (NO) and cytokines (TNF-α and IL-6) as well as the phagocytosis of RAW264.7 macrophages. Moreover, TLR2 was found to be a pattern recognition receptor (PRR) of FCPW80-2, and its related mitogen-activated protein kinases (MAPKs), including p-ERK, p-JNK and p-p38, were rapidly upregulated by FCPW80-2 in RAW264.7 macrophages. Furthermore, FCPW80-2 could not only upregulate the expression of p-p65 and p-IκB-α, but also cause the translocation of nuclear factor-kappa B (NF-κB) p65 from cytosol to nuclei in RAW264.7 macrophages. The results demonstrated that MAPK and NF-κB signalling pathways participated in FCPW80-2-induced macrophage activation and FCPW80-2 could be developed as a potential immunomodulating functional food.

Cordyceps militaris Fraction induces apoptosis and G2/M Arrest via c-Jun N-Terminal kinase signaling pathway in oral squamous carcinoma KB Cells.

BACKGROUND: Cordyceps militaris fraction (CMF) has been shown to possess in vitro antitumor activity against human chronic myeloid leukemia K562 cells in our previous research. MATERIALS AND METHODS: The in vitro inhibitory activities of CMF on the growth of KB cells were evaluated by viability assay. The apoptotic and cell cycle influences of CMF were detected by 4',6-diamidino-2-phenylindole staining and flow cytometry assay. The expression of different apoptosis-associated proteins and cell cycle regulatory proteins was examined by Western blot assay. The nuclear localization of c-Jun was observed by fluorescence staining. OBJECTIVE: The objective of this study was to investigate the antiproliferative effect of CMF as well as the mechanism underlying the apoptosis and cell cycle arrest it induces in KB cells. RESULTS: CMF suppressed KB cells' proliferation in a dose- and time-dependent manner. Flow cytometric analysis indicated that CMF induced G2/M cell cycle arrest and apoptosis. Western blot analysis revealed that CMF induced caspase-3, caspase-9, and PARP cleavages, and increased the Bax/Bcl-2 ratio. CMF also led to increased expression of p21, decreased expression of cyclin B1, mitotic phosphatase cdc25c, and mitotic kinase cdc2, as well as unchanged expression of p53. In addition, CMF stimulated c-Jun N-terminal kinases (JNK) protein phosphorylations, resulting in upregulated expression of c-Jun and nuclear localization of c-Jun. Pretreatment with JNK inhibitor SP600125 suppressed CMF-induced apoptosis and G2/M arrest. CONCLUSIONS: CMF is capable of modulating c-Jun caspase and Bcl-2 family proteins through JNK-dependent apoptosis, which results in G2/M phase arrest in KB cells. CMF could be developed as a promising candidate for the new antitumor agents. SUMMARY: CMF exhibited strong anticancer activity against oral squamous carcinoma KB cellsCMF inhibited KB cells' proliferation via induction of apoptosis and G2/M cell cycle arrestCMF activated JNK signaling pathway and promoted the nuclear localization of c-JunCMF regulated the apoptosis- and cell cycle-related proteins in a manner dependent on JNK/c-Jun pathway. Abbreviations used: CMF: Cordyceps militaris fraction; OSCC: Oral squamous cell carcinoma; JNK: c-Jun N-terminal kinase.

Structural elucidation and immunostimulatory activity of a new polysaccharide from Cordyceps militaris.

A new polysaccharide (CMPB90-1) was isolated from cultured Cordyceps militaris by alkaline extraction. The chemical structure of CMPB90-1 was determined by analysis of physicochemical and spectral data. The backbone of CMPB90-1 is composed of (1→6)-linked α-d-glucopyranosyl and (1→3)-linked α-d-glucopyranosyl residues, with branching at O-6, which consists of (1→4)-linked ß-d-mannopyranosyl and (1→6)-linked α-d-glucopyranosyl residues, respectively. ß-d-Galactopyranosyl residues is the terminal unit. In vitro immunomodulatory assay revealed that CMPB90-1 promoted proliferation of splenic lymphocytes, enhanced cytotoxicity of NK cells and promoted lymphocyte secretion of the cytokine interleukin-2. Besides, CMPB90-1 upregulated T-cell subpopulation, strengthened phagocytosis function of macrophages and induced their M1 polarization. The mechanism of the effects might be due to the activation of TLR2, MAPK and NF-κB pathways. The results proposed that CMPB90-1 can be researched and developed as a new functional food.

Isolation, characterization and bioactivities of a new polysaccharide from Annona squamosa and its sulfated derivative.

A new water-soluble polysaccharide, designated as ASPW80-1, was first isolated from the fruit pulp of Annona squamosa. The structure of ASPW80-1 was elucidated based on the physicochemical and instrumental analyses. The results indicated that ASPW80-1 was a homogeneous heteropolysaccharide with an average molecular weight of 2.29×10(5)Da. Another novel modified polysaccharide, the sulfated derivative of ASPW80-1 namely as ASPW80-M1, was also synthesized. The ultra-structures of both ASPW80-1 and ASPW80-M1 were further characterized by scanning electron microscopy and atomic force microscopy. The antioxidant assays showed that ASPW80-1 and ASPW80-M1 exhibited DPPH and hydroxyl radicals scavenging activities. The results of immunomodulatory assays in vitro showed that ASPW80-1 and ASPW80-M1 could markedly promote the proliferation of mouse splenocytes. These results proposed that ASPW80-M1 might be proposed to be developed as a potential value-added product with the activities of immunomodulator and free-radical inhibitors.

A novel polysaccharide isolated from Litchi chinensis by using a simulated gastric medium and its immunomodulatory activity.

A novel polysaccharide (LCPA50-S1) with immunomodulatory activity was extracted with simulated gastric medium from Litchi chinensis, and purified by DEAE-52 cellulose column, Sephadex G-50 column and Sephacryl S-300 HR chromatography. The structural characteristics of LCPA50-S1 were expounded through complete acid hydrolysis, partial acid hydrolysis, methylation and instrumental analysis. The results demonstrated that LCPA50-S1 is a heteropolysaccharide with a molecular weight of 1.58 × 10(5) Da. The backbone was composed of (1→4)-linked ß-D-glucopyranosyl residues, (1→6)-linked ß-D-galactopyranosyl, (1→3,6)-linked ß-D-galactopyranosyl residues, (1→4,6)-linked α-D-glucopyranosyl residues and branched at O-6. The branches were consisted of (1→2)-linked α-L-rhamnopyranosyl residues, (1→4)-linked ß-D-glucopyranosyl residues, and (1→6)-linked ß-D-galactopyranosyl, terminated with (1→)-linked α-L-arabinopyranosyl residues and (1→)-linked ß-D-galactopyranosyl residues, respectively. The immunoregulatory activity of LCPA50-S1 was evaluated through determination the effect of LCPA50-S1 on nitric oxide (NO) production of RAW264.7 macrophages and spleen lymphocyte proliferation as well as its cytokines secretion level. The results demonstrated that LCPA50-S1 increased NO and TNF-α production in RAW264.7 macrophages significantly, enhanced the proliferation as well as the interleukin-2 (IL-2) production of splenocytes. The data indicated that LCPA50-S1 had the potential to be explored as a novel natural immunomodulator for application in functional foods and medicine.

Structural characterization and biological activities of a novel polysaccharide from cultured Cordyceps militaris and its sulfated derivative.

A novel polysaccharide (CMPA90-1; compound 1) was isolated from the cultured fruiting bodies of Cordyceps militaris. The chemical structure of compound 1 was elucidated by acid hydrolysis, periodate oxidation, Smith degradation, and methylation analysis, along with Fourier transform infrared spectroscopy, high-performance anion-exchange chromatography coupled with pulsed amperometric detection, gas chromatography-mass spectrometry, and one-dimensional [(1)H and (13)C nuclear magnetic resonance (NMR)] and two-dimensional NMR (heteronuclear single-quantum coherence and heteronuclear multiple-bond correlation). Sulfation of compound 1 by the chlorosulfonic acid-pyridine (CSA-Pyr) method led to synthesis of its sulfated analogue (CMPA90-M1; compound 2). The ultrastructures of both compounds 1 and 2 were further characterized by scanning electron microscopy and atomic force microscopy. The results of antioxidant assays showed that compounds 1 and 2 exhibited free-radical-scavenging effects, ferrous-ion-chelating ability, and reducing power. Also, in the cytotoxicity assay, compounds 1 and 2 showed inhibitory activity against A549 cells, with IC50 values of 39.08 and 17.33 µg/mL, respectively.