Macrophage immunomodulatory activity of polysaccharides isolated from Opuntia polyacantha

Opuntioideae cactus stem Bioimaging analysis: Bridging taxonomy and antimicrobial research

This study presents a comprehensive scanning electron microscopy (SEM) analysis of Opuntioideae cactus stems indigenous to the arid regions of Saudi Arabia, elucidating their intricate microstructural features. The findings not only advance taxonomic understanding by aiding in species differentiation but also reveal the antimicrobial potential of these cacti, highlighting their significance as valuable natural resources for both ecological and pharmaceutical applications. The present study is aimed to present the stem epidermal anatomical description of Opuntioideae (Cactaceae) belonging to genus Opuntia (five Species), Cylindropuntia (two Species), and Austrocylindropuntia (one Species) as tool for systematic identification. Stem epidermal anatomical features represent here are epidermal cells, stomatal complex, subsidiary cells, and trichomes findings was observed using light microscope and SEM. The stem epidermal sections were made by heating in test tube containing lactic acid and nitric acid protocol. In anatomical findings, irregular, zigzag, wavy, and polygonal epidermal cells with sinuate, sinuous, and straight anticlinal walls were observed. Quantitatively minimum length (28.05 ± 2.05 μm) and width (23.15 ± 3.41 μm) of epidermal cells were noted in Cylindropuntia kleiniae. Paracytic type of stomata present was observed in all species with kidney-shaped guard cell present in six species, and in Opuntia macrocentra and Austrocylindropuntia subulata, dumbbell-shaped guard cells were observed. The largest length of stomata (53.25 ± 2.05 μm) and width of stomata (35.10 ± 5.19 μm) were observed in Opuntia monacantha. In present research work, stem anatomical features show many diverse characters are of special attention for plant taxonomist for the correct identification and provide baseline for further study in subfamily Opuntiodeae. RESEARCH HIGHLIGHTS: The intricate microstructures of Opuntioideae cactus stems. Investigating the antimicrobial potential of compounds found within Opuntioideae cactus stems. Correlations between the unique structural features observed through SEM and the antimicrobial activity of Opuntioideae cactus stem extracts.

A polysaccharide from Epiphyllum oxypetalum (DC.) Haw. and its immunomodulatory activity

A polysaccharide (EOP) from Epiphyllum oxypetalum (DC.) Haw. was isolated and identified, and its immunomodulatory activity was evaluated both in vitro and in vivo. By using multispectral analysis, EOP was determined to be composed of rhamnose, arabinose, galactose, and galacturonic acid at a molar ratio of 26.65:11.48:53.79:6.04, and its molecular weight was 5.77 × 106 Da. In addition, backbone structure of EOP was determined to consist of (1 → 4)-linked β-Galp, (1 → 2)-linked β-Rhap, (1 → 3,4)-linked β-Galp, (1 → 2,4)-linked β-Rhap and (1 → 4) -linked α-GalpA, terminating with t-β-Arap and t-β-Galp. The in vitro immunomodulatory activity assay on RAW 264.7 cell showed that EOP increased the proliferation of macrophages, enhanced its phagocytic capability, and promoted the production of cytokines including nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). Furthermore, the in vivo evaluation on zebrafish showed that EOP could reduce the residual content of fluorescent microspheres in zebrafish, which indicated that EOP had the capability to enhance the macrophage phagocytosis. All results suggested that EOP showed a complex structure and exhibited significant immunomodulatory activity both in vitro and in vivo that had the potential to be utilized valuably in food and medicine industries.

Structural properties and immune-enhancing activities of galactan isolated from red seaweed Grateloupia filicina

A water-soluble polysaccharide (GFP) was isolated from Grateloupia filicina and fractionated using a DEAE Sepharose Fast Flow column to evaluate immunostimulatory activity. Carbohydrates (62.0%-68.4%) and sulfates (29.3%-34.3%) were the major components of GFP and its fractions (GFP-1 and GFP-2), with relatively lower levels of proteins (4.5%-15.4%) and uronic acid (1.4%-3.9%). The average molecular weight (Mw ) for GFP and its fractions was calculated between 98.2%-243.7 kDa. The polysaccharides were composed of galactose (62.1%-87.2%), glucose (4.5%-33.2%), xylose (3.1%-5.3%), mannose (1.4%-2.2%), rhamnose (1.2%-2.0%), and arabinose (0.9%-1.7%) units connected through →3)-Galp-(1→, →4)-Galp-(1→, →2)-Galp-(1→, →6)-Galp-(1→, →3,4)-Galp -(1→, →3,6)-Galp-(1→, →4,6)-Galp-(1→, →3,4,6)-Galp-(1→, →2,3)-Galp-(1→, →2,4)-Galp-(1→, →4)-Glcp-(1→, →6)-Glcp-(1→ and →4,6)-Glcp-(1→residues. The isolated polysaccharides effectively induced RAW264.7 murine macrophages by releasing nitric oxide (NO) and various cytokines via nuclear factor kappa light chain enhancer of activated B cells (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Further, the expression of toll-like receptor-2 (TLR-2) and TLR-4 in RAW264.7 cells indicated their activation through TLR-2 and TLR-4 binding receptors. Among the polysaccharides, GFP-1 highly stimulated the activation of RAW264.7 cells, which was mainly constituted of (→1) terminal-D-galactopyranosyl, (1→3)-linked-ᴅ-galactopyranosyl, (1→4)-linked-ᴅ-galactopyranosyl and (1→3,4) -linked-ᴅ-galactopyranosyl residues. These findings demonstrate that GFP-1 from G. filicina are effective at stimulating the immune system and this warrants further investigation to determine potential biomedical applications.

Immunomodulatory Activity of Polysaccharides Isolated from Saussurea salicifolia L. and Saussurea frolovii Ledeb

The genus Saussurea has been used in the preparation of therapies for a number of medical problems, yet not much is known about the therapeutic high-molecular-weight compounds present in extracts from these plants. Since polysaccharides are important in immune modulation, we investigated the chemical composition and immunomodulatory activity of Saussurea salicifolia L. and Saussurea frolovii Ledeb polysaccharides. Water-soluble polysaccharides from the aerial parts of these plants were extracted using water at pHs of 2 and 6 and subsequently precipitated in ethanol to obtain fractions SSP2 and SSP6 from S. salicifolia and fractions SSF2 and SSF6 from S. frolovii. The molecular weights of fractions SSP2, SSP6, SFP2, and SFP6 were estimated to be 143.7, 113.2, 75.3, and 64.3 kDa, respectively. The polysaccharides from S. frolovii contained xylose (67.1-71.7%) and glucose (28.3-32.9%), whereas the polysaccharides from S. frolovii contained xylose (63.1-76.7%), glucose (11.8-19.2%), galactose (4.7-8.3%), and rhamnose (6.8-9.4%). Fractions SSP2, SSP6, and SFP2 stimulated nitric oxide (NO) production by murine macrophages, and NO production induced by SSP2, SSP6, and SFP2 was not inhibited by polymyxin B treatment of the fractions, whereaspolymyxin B treatment diminished the effects of SFP6, suggesting that SFP6 could contain lipopolysaccharide (LPS). The LPS-free fractions SSP2, SSP6, and SFP2 had potent immunomodulatory activity, induced NO production, and activated transcription factors NF-κB/AP-1 in human monocytic THP-1 cells and cytokine production by human MonoMac-6 monocytic cells, including interleukin (IL)-1α, IL-1β, IL-6, granulocyte macrophage colony-stimulating factor (GM-CSF), interferon-γ, monocyte chemotactic protein 1 (MCP-1), and tumor necrosis factor (TNF). These data suggest that at least part of the beneficial therapeutic effects reported for water extracts of the Saussurea species are due to the modulation of leukocyte functions by polysaccharides.

High light triggers flavonoid and polysaccharide synthesis through DoHY5-dependent signaling in Dendrobium officinale

Dendrobium officinale is edible and has medicinal and ornamental functions. Polysaccharides and flavonoids, including anthocyanins, are important components of D. officinale that largely determine the nutritional quality and consumer appeal. There is a need to study the molecular mechanisms regulating anthocyanin and polysaccharide biosynthesis to enhance D. officinale quality and its market value. Here, we report that high light (HL) induced the accumulation of polysaccharides, particularly mannose, as well as anthocyanin accumulation, resulting in red stems. Metabolome and transcriptome analyses revealed that most of the flavonoids showed large changes in abundance, and flavonoid and polysaccharide biosynthesis was significantly activated under HL treatment. Interestingly, DoHY5 expression was also highly induced. Biochemical analyses demonstrated that DoHY5 directly binds to the promoters of DoF3H1 (involved in anthocyanin biosynthesis), DoGMPP2, and DoPMT28 (involved in polysaccharide biosynthesis) to activate their expression, thereby promoting anthocyanin and polysaccharide accumulation in D. officinale stems. DoHY5 silencing decreased flavonoid- and polysaccharide-related gene expression and reduced anthocyanin and polysaccharide accumulation, whereas DoHY5 overexpression had the opposite effects. Notably, naturally occurring red-stemmed D. officinale plants similarly have high levels of anthocyanin and polysaccharide accumulation and biosynthesis gene expression. Our results reveal a previously undiscovered role of DoHY5 in co-regulating anthocyanin and polysaccharide biosynthesis under HL conditions, improving our understanding of the mechanisms regulating stem color and determining nutritional quality in D. officinale. Collectively, our results propose a robust and simple strategy for significantly increasing anthocyanin and polysaccharide levels and subsequently improving the nutritional quality of D. officinale.

Lactic acid bacteria-derived exopolysaccharide: Formation, immunomodulatory ability, health effects, and structure-function relationship

Exopolysaccharides (EPSs) synthesized by lactic acid bacteria (LAB) have implications for host health and act as food ingredients. Due to the variability of LAB-EPS (lactic acid bacteria-derived exopolysaccharide) gene clusters, especially the glycosyltransferase genes that determine monosaccharide composition, the structure of EPS is very rich. EPSs are synthesized by LAB through the extracellular synthesis pathway and the Wzx/Wzy-dependent pathway. LAB-EPS has a strong immunomodulatory ability. The EPSs produced by different genera of LAB, especially Lactobacillus, Leuconostoc, and Streptococcus, have different immunomodulatory abilities because of their specific structures. LAB-EPS possesses other health effects, including antitumor, antioxidant, intestinal barrier repair, antimicrobial, antiviral, and cholesterol-lowering activities. The bioactivities of LAB-EPS are tightly related to their structures such us monosaccharide composition, glycosidic bonds, and molecular weight (MW). For the excellent physicochemical property, LAB-EPS acts as product improvers in dairy, bakery food, and meat in terms of stability, emulsification, thickening, and gelling. We systematically summarize the detailed process of EPS from synthesis to application, with emphasis on physiological mechanisms of EPS, and specific structure-function relationship, which provides theoretical support for the potential commercial value in the pharmaceutical, chemical, food, and cosmetic industries.

Structural elucidation of the exopolysaccharide from Streptococcus thermophilus XJ53 and the effect of its molecular weight on immune activity

EPS53, a homogeneous exopolysaccharide (EPS) was isolated from Streptococcus thermophiles XJ53 fermented in skimmed milk via anion exchange column chromatography. The relative molecular weight of EPS53 was above 6.7 × 10⁵ g/mol; its repeating structural unit of EPS53 consisted of β-T-Galp, β-1,3-Galf, α-1,3-Glcp and β-1,3,6-Glcp residues in a molar ratio of 1:1:1:1, with β-T-Galp attached to the O-6 position of β-1,3,6-Glcp，identical to the EPS produced from S. thermophilus SFi39. EPS53-D, purified under similar conditions as EPS53 except for the deproteinization of trichloroacetic acid (TCA), had a lower molecular weight but the same repeating structural unit. The effects of EPS53 and EPS53-D on proliferation, phagocytosis and nitric oxide (NO) release of macrophage RAW264.7 were compared. EPS53 exhibited stronger immune activity than EPS53-D, suggesting that the molecular weight might have an important effect on the activity of EPS molecules. Treatment with TCA might affect the activities of native EPSs produced by fermentation.

Characterization and therapeutic effect of Sargassum coreanum fucoidan that inhibits lipopolysaccharide-induced inflammation in RAW 264.7 macrophages by blocking NF-κB signaling

Inflammation is a complex host-protective response against harmful stimuli involving macrophage activation that results in secretion of inflammatory mediators, like nitric oxide (NO), pro-inflammatory cytokines, and prostaglandin E2 (PGE2). In this study, we evaluated fucoidan isolated using Viscozyme-assisted enzymatic extraction of Sargassum coreanum extract against lipopolysaccharide (LPS)-stimulated inflammation in RAW 264.7 macrophages and zebrafish model. Among the fucoidan fractions isolated using ion exchange chromatography, SCVF5 showed the highest sulfate and fucose contents based on chemical composition and monosaccharide analysis. Fourier-transform infrared (FT-IR) spectroscopy confirmed the presence of sulfate esters by the stretching vibrations of the SO peak at 1240 cm-1. SCVF5 showed anti-inflammatory effects by inhibiting NO and PGE2 generation in LPS-stimulated RAW 264.7 macrophages by downregulating inducible NO synthase and cyclooxygenase-2 expression. Treatment with SCVF5 suppressed pro-inflammatory cytokine production, such as TNF-α, (IL)-1β, and IL-6 by modulating the nuclear factor-kappa B signaling cascade in LPS-induced RAW 264.7 cells. Furthermore, in vivo results showed that SCVF5 can potentially downregulate LPS-induced toxicity, cell death, and NO production in LPS-induced zebrafish model. Collectively, these results suggest that S. coreanum fucoidan has remarkable anti-inflammatory activity in vitro and in vivo and may have potential applications in the functional food, cosmetic, and pharmaceutical industries.

FTIR Characterization of Sulfated Polysaccharides Obtained from Macrocystis integrifolia Algae and Verification of Their Antiangiogenic and Immunomodulatory Potency In Vitro and In Vivo

The aim of this study was to evaluate the antiangiogenic and immunomodulatory potential of sulfated polysaccharides from the marine algae Macrocystis integrifolia characterized by FTIR. The cytotoxicity of sulfated polysaccharides was evaluated using the 3-(4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide (MTT) assay. Antiangiogenic activity was evaluated using the chicken chorioallantoic membrane (CAM) assay. Immunomodulatory activity was determined on macrophage functionality and allergic response. The results showed that sulfated polysaccharides significantly decreased angiogenesis in chicken chorioallantoic membranes (p < 0.05). Likewise, they inhibited in vivo chemotaxis and in vitro phagocytosis, the transcription process of genes that code the enzymes cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2) and nitric oxide synthase-2 (NOS-2) and the nuclear factor kappa-light chain enhancer of activated B cells (NF-κB), showing immunomodulatory properties on the allergic response, as well as an in vivo inhibitory effect in the ovalbumin-induced inflammatory allergy model (OVA) and inhibited lymphocyte proliferation specific to the OVA antigen in immunized mice. Finally, these compounds inhibited the histamine-induced skin reaction in rats, the production of immunoglobulin E (IgE) in mice, and the passive response to skin anaphylaxis in rats. Therefore, the results of this research showed the potential of these compounds to be a promising source for the development of antiangiogenic and immunomodulatory drugs.

In Situ Release of Ulvan from Crosslinked Ulvan/Chitosan Complex Films and Their Evaluation as Wound Dressings

When a wound forms due to any injuries, it should be covered with a functional wound dressing for accelerating wound healing and reducing infection. In this study, crosslinked ulvan/chitosan complex films were prepared with or without the addition of glycerol and chlorophyll, and their wound healing properties were evaluated for potential application in wound dressing. The results showed that the tensile strength and elongation at break of the prepared ulvan/chitosan complex films were 2.23-2.48 MPa and 83.8-108.5%, respectively. Moreover, their water vapor transmission rates (WVTRs) were in the range of 1791-2029 g/m²-day, providing suitable environment for wound healing. Particularly, these complex films could release ulvan in situ in a short time, and the film with chlorophyll added had the highest release rate, reaching 62.8% after 20 min of releasing. In vitro studies showed that they were biocompatible toward NIH 3T3 and HaCaT cells, and promoted the migration of NIH 3T3 cells. These complex films could protect HaCaT cells from oxidative damage and reduce the production of reactive oxygen species (ROS); the addition of chlorophyll also effectively reduced the inflammatory response induced by LPS as found in the reduction in both NO and IL-6. Animal models showed that the complex films added with glycerol and chlorophyll could promote wound healing in the early stage, while accelerating the regeneration of dermal glands and collagen production. Briefly, these ulvan/chitosan complex films had good physiochemical properties and biological activity, and could accelerate wound healing both in vitro and in vivo.

Novel Pectic Polysaccharides Isolated from Immature Honey Pomelo Fruit with High Immunomodulatory Activity

A novel pectic polysaccharide (HPP-1) with high immunomodulatory activity was extracted and isolated from the immature honey pomelo fruit (Citrus grandis). Characterization of its chemical structure indicated that HPP-1 had a molecular weight of 59,024 D. In addition, HPP-1 was primarily composed of rhamnose, arabinose, fucose, mannose, and galactose at a molar ratio of 1.00:11.12:2.26:0.56:6.40. Fourier-transform infrared spectroscopy, periodic acid oxidation, and Smith degradation results showed that HPP-1 had α- and β-glycosidic linkages and 1 → 2, 1 → 4, 1 → 6, and 1 → 3 glycosidic bonds. ¹³C NMR and ¹H NMR analyses revealed that the main glycogroups included 1,4-D-GalA, 1,6-β-D-Gal, 1,6-β-D-Man, 1,3-α-L-Ara, and 1,2-α-L-Rha. Immunomodulatory bioactivity analysis using a macrophage RAW264.7 model in vitro revealed that NO, TNF-α, and IL-6 secretions were all considerably increased by HPP-1. Moreover, RT-PCR results showed that HPP-1-induced iNOS, TNF-α, and IL-6 expression was significantly increased in macrophages. HPP-1-mediated activation in macrophages was due to the stimulation of the NF-κB and MAPK signaling pathways based on western blot analyses. HPP-1 extracted from immature honey pomelo fruit has potential applications as an immunomodulatory supplement.

The polysaccharide from Camellia oleifera fruit shell enhances immune responses via activating MAPKs and NF-κB signaling pathways in RAW264.7 macrophages

Background

Macrophage plays an important role in innate immune responses by secreting immune molecules and phagocytosis. Camellia oleifera fruit shell, accounting for approximately 60% weight of the single C. oleifera fruit, is rich in polysaccharides and has several biological activities such as anti-oxidation, lipid regulation and anticancer. However, the immunomodulatory activity of the polysaccharide from C. oleifera fruit shells (CPS) has not been reported.

Objective

This study aimed to investigate the immunomodulatory activities and mechanisms of CPS in RAW264.7 macrophages.

Methods

The Methyl Thiazolyl Tetrazolium (MTT) method was used to evaluate the effect of CPS on the cell viability of RAW264.7 macrophages, and cell morphology was pictured using microscope. The production of immune-related molecules, including nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor α (TNFα), interleukin (IL)-1β and IL-6, was detected by Griess assay and enzyme-linked immunosorbent assay (ELISA). The protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX2) and the phosphorylation level of mitogen-activated protein kinases (MAPKs) were analyzed through western blotting. The mRNA levels of related genes were tested using reverse transcription-polymerase chain reaction (RT-PCR). The nuclear translocation of nuclear factor-kappa B (NF-κB) was detected using immunofluorescence technology.

Results

The results indicated that CPS treatment stimulated the production of NO and PGE2 and significantly enhanced the protein expression of iNOS and COX2 with little effect on the cell morphology and viability. Also, the secretion and mRNA levels of TNFα were increased by the treatment of CPS. In addition, CPS treatment markedly upregulated the phosphorylation level of MAPKs including Extracellular Signal Regulated Kinase (ERK), P38, and c-Jun N-terminal Kinase (JNK) at different time points and caused the activation and nuclear translocation of NF-κB.

Conclusion

Our data implied that CPS exerts immunomodulatory activities by activating MAPKs and NF-κB signaling pathways in RAW264.7 macrophages.

Isolation, Structural Characterization, and Hypoglycemic Activities In Vitro of Polysaccharides from Pleurotus eryngii

Pleurotus eryngii (PE) is an edible mushroom with high nutritional value. Pleurotus eryngii polysaccharides (PEPs) are one of the main active ingredients and manifest a great variety of biological activities. This study mainly focused on the chemical characterization and biological activities of PEPs, which were separated into two fractions (named WPS and P-1). WPS is mainly dominated by β-glycosidic bonds and contains α-glycosidic bonds, and P-1 only contains α-glycosidic bonds. The molecular weights of WPS and P-1 were 4.5 × 10⁵ Da and 2.2 × 10⁴ Da. The result of GC indicated that two the fractions were composed of rhamnose, arabinose, xylose, mannose, glucose, and galactose, with a ratio of 0.35:0.24:0.45:0.24:28.78:1.10 for WPS and 0.95:0.64:0.66:1.84:60.69:0.67 for P-1. The advanced structure studies indicated that the two fractions had no triple-helical structure, where WPS had a dense structure and P-1 had a loose structure. In addition, the antioxidant activity of WPS surpassed P-1, and the two fractions also exhibited a high hypoglycemic activity via inhibiting α-glycosidase activities and promoting the expression of PI3K-AKT signaling pathway based on in vitro assay and cell experiments.

The structures of two glucomannans from Bletilla formosana and their protective effect on inflammation via inhibiting NF-κB pathway

Bletilla formosana is a traditional Chinese herbal medicine and is widely consumed as foods and medicines in China. However, the chemical structure and bioactivity of its polysaccharides remain unknown. Herein, two new polysaccharides, BFP60 and BFP80, with molecular weights of 3.99 kDa and 10.07 kDa, respectively, were isolated and purified from dried tuber of B. formosana. Structural analysis suggested that BFP60 and BFP80 may have backbone consisted of →4)-β-d-Man-(1→,→4)-β-d-Glc-(1→,→4)-2-O-acetyl-β-d-Man-(1→, and →4)-3-O-acetyl-β-d-Man-(1→. Inflammation assay in LPS-induced RAW264.7 cells showed that the productions of NO and pro-inflammatory cytokines including IL-6, IL-1β, TNF-α, and IFN-γ were significantly reduced, and the expression of iNOS, COX-2, and target proteins in the NF-κB pathway were suppressed after BFP60 and BFP80 pretreatment. These findings indicated that this novel polysaccharide had significant inflammatory protective effects in vitro.

Effects of cactus Opuntia dillenii polysaccharide-based coatings loaded with glutathione on the preservation of freshly cut Chinese water chestnut

This study explored the effects of coatings based on glutathione-loaded cactus Opuntia dillenii polysaccharide (ODP) on the preservation of freshly cut Chinese water chestnut. Freshly cut Chinese water chestnut samples were treated with one of the three dipping solutions, namely, distilled water (control), 0.4 % glutathione (treatment-1) or 1 % ODP + 0.4 % glutathione (treatment-2) and stored at 3 °C for 10 days. All treatments suppressed respiration rate, weight loss and decreases in firmness and browning and increased soluble solid content and likeness score compared with the control (P < 0.05). In terms of sensory quality, treatment-2 extended the shelf life of the freshly cut Chinese water chestnut at least by 6 days compared with the control group. Results verified that treatment with ODP-based coatings incorporated with glutathione may be a promising method for preserving freshly cut Chinese water chestnut.

Anti-Inflammatory Effects of Opuntia Milpa Alta Polysaccharides Fermented by Lactic Acid Bacteria in Human Keratinocyte HaCaT Cells

Opuntia milpa alta polysaccharides (ODP) are bioactive compounds extracted from Opuntia milpa alta and widely used in the treatment of diseases, but the therapeutic mechanism of ODP on inflammatory injury remains unclear. Therefore, this study explores the effects and mechanisms of ODP in lipopolysaccharide (LPS)-induced inflammation of human keratinocytes (HaCaT). In this experiment, ODP was extracted via the water extraction and fermentation methods, respectively. LPS was then used to induce inflammatory damage in HaCaT cells, and the stimulated cells were treated with different concentrations of ODP. Cell viability was detected by MTT assay, and the concentrations of COX-2, iNOS, IL-6, IL-8, IL-10 and TNF-α were determined by enzyme-linked immunosorbent assay (ELISA). Changes in inflammatory cytokines and related mRNA expression were observed to assess LPS-induced cell damage. In the experiment, it was found that the LPS stimulation of HaCaT cells can induce cellular inflammatory response, reduce cell viability, increase cell apoptosis and increase the expression of COX-2, iNOS, IL-6, IL-8, IL-10 and TNF-α. However, the experimental data shows that ODP can reverse the above results by increasing cell viability, inhibiting cell apoptosis, reducing the expression of the above genes and inactivating antioxidant pathways, which revealed the specific mechanism of ODP repairing LPS-induced inflammatory damage to Hacat cell. In addition, The experimental results showed that fermentation could improve the anti-inflammatory effect of ODP. In conclusion, our experimental results indicate that ODP fermented by lactic acid bacteria can be used as an anti-inflammatory agent.

Structural Characterization of Degraded Lycium barbarum L. Leaves’ Polysaccharide Using Ascorbic Acid and Hydrogen Peroxide

Plant-derived polysaccharide’s conformation and chain structure play a key role in their various biological activities. Lycium barbarum L. leaves’ polysaccharide is well renowned for its health functions. However, its functional bioactivities are greatly hindered by its compact globular structure and high molecular weight. To overcome such issue and to improve the functional bioactivities of the polysaccharides, degradation is usually used to modify the polysaccharides conformation. In this study, the ethanol extract containing crude Lycium barbarum L. leaves’ polysaccharide was first extracted, further characterized, and subsequently chemically modified with vitamin C (Ascorbic acid) and hydrogen peroxide (H₂O₂) to produce degraded Lycium barbarum L. leaves’ polysaccharide. To explore the degradation effect, both polysaccharides were further characterized using inductively coupled plasma mass spectrometry (ICP-MS), gas chromatography–mass spectrometry (GC–MS), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), high performance gel permeation chromatography (HPGPC), and scanning electron microscope (SEM). Results shown that both polysaccharides were rich in sugar and degradation had no significant major functional group transformation effect on the degraded product composition. However, the molecular weight (Mw) had decreased significantly from 223.5 kDa to 64.3 kDa after degradation, indicating significant changes in the polysaccharides molecular structure caused by degradation.

The regulating effect of Tibet Opuntia ficus-indica (Linn.) Mill. polysaccharides on the intestinal flora of cyclophosphamide-induced immunocompromised mice

The stem of Opuntia species, a traditional medicinal plant, is widely used as food and functional raw material because of its rich polysaccharide content. There have been many studies on the immune function of polysaccharides from Opuntia stem, but only few have examined this function with respect to intestinal microbes. In this study, the effects of different concentrations of Opuntia stem polysaccharides on the immunity and intestinal microflora of cyclophosphamide (CTX)-induced immunocompromised mice were explored. The results showed that Tibet Opuntia ficus-indica (Linn.) Mill. polysaccharides (ODPs) could effectively increase the white blood cells (WBC) count index of mice and improve their thymus and spleen indices, while effectively promoting the secretion of IL-4, IL-1β, TNF-α and IFN-γ, with these effects being dependent on the concentration of crude polysaccharides. The intake of ODPs significantly regulated the relative abundance of Lactobacillus, Bacteroides and Akkermansia, and the new dominant intestinal bacterial species were Deferribacteres, Actinomycetes, Firmicutes, Tenericutes, Actinomycetes and Pasteurella. In addition, the ODPs could effectively enhance the metabolic level of lysine synthesis and decomposition, regulate the gene expression level after immune disorders, and enhance the overall health of the immunodeficient mice.

Understanding immune-modulatory efficacy in vitro

Boosting or suppressing our immune system represents an attractive adjunct in the treatment of infections including SARS-CoV-2, cancer, AIDS, malnutrition, age related problems and some inflammatory disorders. Thus, there has been a growing interest in exploring and developing novel drugs, natural or synthetic, that can manipulate our defence mechanism. Many of such studies, reported till date, have been designed to explore effect of the therapeutic on function of macrophages, being a key component in innate immune system. Indeed, RAW264.7, J774A.1, THP-1 and U937 cell lines act as ideal model systems for preliminary investigation and selection of dose for in vivo studies. Several bioassays have been standardized so far where many techniques require high throughput instruments, cost effective reagents and technical assistance that may hinder many scholars to perform a method demanding compilation of available protocols. In this review, we have taken an attempt for the first time to congregate commonly used in vitro immune-modulating techniques explaining their principles. The study detected that among about 40 different assays and more than 150 sets of primers, the methods of cell proliferation by MTT, phagocytosis by neutral red, NO detection by Griess reaction and estimation of expression of TLRs, COX-2, iNOS, TNF-α, IL-6 and IL-1β by PCR have been the most widely used to screen the therapeutics under investigation.

Structure, immunostimulatory activity, and the effect of ameliorating airway inflammation of polysaccharides from Pyrus sinkiangensis Yu

Purified acid polysaccharides PSAP-1 and PSAP-2 with apparent molecular weights of 64.6 and 38.9 kDa, respectively, were isolated from Pyrus sinkiangensis Yu. through combined techniques of ion-exchange and gel permeation chromatography. Both polysaccharides were composed of predominant amounts of GalA and small amounts of Ara, Rha, and Gal. They are deduced to be native pectin-type polysaccharides containing the HG backbone consisting of α-1,4-GalAp and methyl-esterified α-1,4-GalAp residues by IR, GC-MS and NMR spectra analyses. The immunoregulatory activity test showed that PSAP-1 and PSAP-2 could increase the cell viability and the release of NO, IL-6, and TNF-α on the RAW264.7 macrophage. It indicated that PSAP-1 and PSAP-2 could increase macrophage-mediated immunostimulatory activity. The airway inflammation test of antiasthmatic mice showed that PSAP-1 could decrease the contents of IL-4, IL-5, and IL-13 and the number of inflammatory cells in BALF and improve the pathological changes in lung tissue. PSAP-1 could also decrease the amount of mucus secreted by goblet cells and the expression levels of NF-κB p65, IκBα, IKK, ERK, JNK, P38, and Muc5ac mRNA and increase the expression levels of TLR2 and TLR4 mRNA in lung tissues. This suggested that PSAP-1 may resist airway inflammation in mice. PSAP-1 and PSAP-2 had potential clinical application value.

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→, β-D-Glcp-(1→, →6)-α-D-Manp-(1→, →4)-α-D-GlcpNAc-(1→, →4)-β-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.

Structural Elucidation and Immunostimulatory Activities of Quinoa Non-starch Polysaccharide Before and After Deproteinization

Non-starch polysaccharides derived from natural resources play a significant role in the field of food science and human health due to their extensive distribution in nature and less toxicity. In this order, the immunostimulatory activity of a non-starch polysaccharide (CQNP) from Chenopodium quinoa was examined before and after deproteination in murine macrophage RAW 264.7 cells. The chemical composition of CQNP and deproteinated-CQNP (D-CQNP) were spectrometrically analysed that revealed the presence of carbohydrate (22.7 ± 0.8% and 39.5 ± 0.8%), protein (41.4 ± 0.5% and 20.8 ± 0.5%) and uronic acid (8.7 ± 0.3% and 6.7 ± 0.2%). The monosaccharide composition results exposed that CQNP possesses a high amount of arabinose (34.5 ± 0.3) followed by galactose (26.5 ± 0.2), glucose (21.9 ± 0.3), rhamnose (7.0 ± 0.1), mannose (6.0 ± 0.1) and xylose (4.2 ± 0.2). However, after deproteination, a difference was found in the order of the monosaccharide components, with galactose (41.1 ± 0.5) as a major unit followed by arabinose (34.7 ± 0.5), rhamnose (10.9 ± 0.2), glucose (6.6 ± 0.2), mannose (3.4 ± 0.2) and xylose (3.2 ± 0.2). Further, D-CQNP potentially stimulate the RAW 264.7 cells through the production of nitric oxide (NO), upregulating inducible nitric oxide synthase (iNOS) and various pro-inflammatory cytokines including interleukin (IL)-1β, IL-6, IL-10, and tumor necrosis factor-alpha (TNF-α). Moreover, stimulation of RAW 264.7 cells by D-CQNP takes place along the NF-κB and the MAPKs signaling pathways through the expression of cluster of differentiation 40 (CD40). This results demonstrate that RAW 264.7 cells are effectively stimulated after removal of the protein content in C. quinoa non-starch polysaccharides, which could be useful for develop a new immunostimulant agent.

Structural characteristics and immune-enhancing activity of an extracellular polysaccharide produced by marine Halomonas sp. 2E1

Microbial polysaccharides from extreme environments, such as cold seeps and hydrothermal vents, usually exhibit novel structural features and diverse biological activities. In this study, an exopolysaccharide (EPS2E1) was isolated from cold-seep bacterium Halomonas sp. 2E1 and its immune-enhancing activity was evaluated. The total sugar content and protein content were determined as 83.1% and 7.9%, respectively. EPS2E1 contained mannose and glucose with the molar ratio of 3.76: 1. The molecular weight was determined to be 47.0 kDa. Structural analysis indicated that EPS2E1 was highly branched, the backbone mainly consisted of →2)-Man-(α-1→ and →2, 6)-Man-(α-1→ with the ratio of 2.45: 1.00. The chain also contained →4)-Glc-(α-1→, →6)-Man-(α-1→ and →3)-Glc-(β-1→. EPS2E1 could significantly increase the production of NO, COX-2, TNF-α, IL-1β and IL-6 by activating the MAPK and NF-κB pathways on RAW264.7 macrophages. EPS2E1 exhibits the potential to be an immunopotentiator in the near future.

Characterization of Different Salt Forms of Chitooligosaccharides and Their Effects on Nitric Oxide Secretion by Macrophages

In this paper, chitooligosaccharides in different salt forms, such as chitooligosaccharide lactate, citrate, adipate, etc., were prepared by the microwave method. They were characterized by SEM, FTIR, NMR, etc., and the nitric oxide (NO) expression was determined in RAW 264.7 cells. The results showed that pure chitooligosaccharide was an irregular spherical shape with rough surface, and its different salt type products are amorphous solid with different honeycomb sizes. In addition to the characteristic absorption peaks of chitooligosaccharides, in FTIR, the characteristic absorption of carboxyl group, methylene group, and aromatic group in corresponding acid appeared. The characteristic absorption peaks of carbon in carboxyl group, hydrogen and carbon in methyl, methylene group, and aromatic group in corresponding acid also appeared in NMR. Therefore, the sugar ring structure and linking mode of chitooligosaccharides did not change after salt formation of chitooligosaccharides. Different salt chitooligosaccharides are completely different in promoting NO secretion by macrophages, and pure chitooligosaccharides are the best.

Structural characterization and immunostimulatory activity in vitro of a glycogen from sea urchin-Strongylocentyotus internedius

Sea urchin possesses both high nutritional and medicinal value. It contains diverse biological active polysaccharides. But there are few studies on its glycogen. In the current study, a glucan (MSGA) was separated from Strongylocentyotus internedius and purified by ion exchange and gel filtration column. Chemical analysis revealed that MSGA with 2.65 × 10⁷ Da is made up entirely of glucose. The analysis of methylation, NMR and mass spectrum demonstrated that MSGA is a highly branched glycogen with α-(1→4) linked gluconic backbone and branched at C-6 (one branch per five residues). In addition, MSGA showed good in vitro immunostimulatory activity via NF-κB and MAPKs pathways. It is considered that high degree of branching is necessary for its activity. However, the relationship between structure and immunostimulatory activity of natural glycogens is difficult to elucidate because the difference in their structural properties. Therefore, much more research is needed in this area.

Anticancer and Immunomodulatory Effects of Polysaccharides

Cancer is one of the leading causes of death and one of the most important public health problems in the world. And every year, millions of new cancers and hundreds of thousands of cancer-related deaths are reported worldwide. In recent decades, a number of biologically active polysaccharides and polysaccharide-protein complexes have been isolated from plants, lichen, algae, yeast, fungi and mushroom, and due to their antitumor and immunomodulatory properties, these compounds have received considerable attention. Overall, the two key mechanisms by which polysaccharides act on tumor cells are direct action (inhibition of cancer cell growth and induction of programmed cell death/apoptosis) and indirect action (stimulation of immunity). Immunosuppressive effects are recognizable in both cancer patients and tumor bearing animals, suggesting that the immune system plays an important role in the immune surveillance of cancer cells. Thus, enhancement of the host immune response has been evaluated as a possible way of inhibiting tumor growth without damaging the host. In addition to their therapeutic and prophylactic properties, the polysaccharides are effective and less toxic than chemotherapy. The anticancer activity and immunomodulatory effects of most polysaccharides have shown the promising and real potential for the benefits of human health.

Effect of Opuntia ficus indica extract on methotrexate-induced testicular injury: a biochemical, docking and histological study

Methotrexate (MTX) is a chemotherapeutic medicine used in the treatment of several types of cancer and inflammatory diseases. It exhibits several drawbacks especially on highly dividing and developing cells. This study aimed to assess the role of Opuntia ficus indica ethanolic extract on testicular damage induced by MTX in rat. MTX was administrated for 10 days (20 mg/kg). Extract of cactus cladodes (Opuntia ficus indica) was given to MTX-treated rats (0.4 g/kg). Spermatozoa were collected from cauda epididymis and analyzed for sperm count and motility. Testis samples were used for histopathological and oxidative stress studies (assessment of malondialdehyde (MDA) levels, protein carbonyls (PCs), catalase (CAT) glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities). Moreover, levels of testosterone were measured in serum by radioimmunoassay. Our results showed that MTX had destructive effects on sperm count and motility associated with significant decrease in testosterone levels in MTX group. This effect was then confirmed by docking results. Testis of MTX group showed increased oxidative stress status. In fact, PCs and MDA were increased and CAT, GPx and SOD were decreased suggesting increased reactive oxygen species and deficiency in enzymatic antioxidant. These findings were associated with disrupted testicular morphology as assessed by histological study. Cladodes extract had protective effects on rat's gonad histology, oxidative stress and improve both sperm parameters (count and motility) and serum testosterone levels. In conclusion, our results suggested that Opuntia ficus indica cladodes extract improved MTX-induced testicular injury and possess potent fertility boosting effects in rats.Communicated by Ramaswamy H. Sarma.

Study of Immunotropic Properties of Water-Soluble Polysaccharides Isolated from Conium maculatum Grass

Addition of water-soluble polysaccharides isolated from Conium maculatum L. to the mouse peritoneal macrophage culture induces classical activation of antigen-presenting cells due to an increase in NO synthase activity and a decrease in arginase expression.

New artificial network model to estimate biological activity of peat humic acids

PURPOSE

This article focuses on new method to estimate biological activity of peat humic acids (HAs) using artificial neural network (ANN) to process spectroscopic measurements in infrared and visible ranges. Conventional approaches generally rely on biological models and direct detection of chemical substances related to bioactivity. These methods proved to be accurate and reliable, but at the expense of speed and simplicity.

MATERIALS AND METHODS

Recently, a conception of quantitative structure-activity relationship (QSAR) has been introduced and successfully implemented to predict effects of HAs on toxicity of polycyclic aromatic hydrocarbons. Our research stems from this conception, but employs multilayer perceptron (MLP) model to improve overall performance. The developed MLP model allowed us to estimate biological activity of the complete vertical peat cores collected from oligotrophic peat bog, located in southern taiga zone of West Siberia (north-eastern spurs of the Great Vasyugan Mire, 56°58' N 82о36' E). In total, 42 samples taken from the cores were collected. The protocol included spectroscopy (in infrared and visible ranges) and biological model with peritoneal activated macrophages as a reference method to directly measure biological activity of HAs.

RESULTS

and discussion. Numerical experiments confirmed consistency of the measured and estimated bioactivity, coefficient of determination R2 = 0.97. These experiments also showed that the MLP model significantly outperforms conventional linear multiple regression models, mainly due to essential nonlinearity of structure-activity relationships.

CONCLUSIONS

Our research demonstrates that biological activity of HAs extracted from peat samples can be estimated using an artificial neural network model trained on infrared and visible spectra.

Immunostimulatory Effects of Polysaccharides from Spirulina platensis In Vivo and Vitro and Their Activation Mechanism on RAW246.7 Macrophages

In this study, Spirulina platensis (S.p.) polysaccharide (PSP) was obtained by ultrasonic-microwave-assisted extraction (UMAE) and purified by an aqueous two-phase system (ATPS). Two different methods were applied to purified Spirulina platensis (S.p.) polysaccharide (PSP), respectively, due to PSP as a complex multi-component system. Three polysaccharide fractions (PSP-1, PSP-2, and PSP-3) with different acidic groups were obtained after PSP was fractionated by the diethyl aminoethyl (DEAE)-52 cellulose chromatography, and two polysaccharide fractions (PSP-L and PSP-H) with different molecular weight were obtained by ultrafiltration centrifugation. The chemoprotective effects of PSP in cyclophosphamide (Cy) treated mice were investigated. The results showed that PSP could significantly increase spleen and thymus index, peripheral white blood cells (PWBC), and peripheral blood lymphocytes (PBL). The in vivo immunostimulatory assays demonstrated that PSP could in dose-dependent increase of TNF-α, IL-10, and IFN-γ production in sera. The in vitro immunostimulatory assays showed that PSP and its fractions (PSPs) could evidently enhance the proliferation of splenocytes and RAW 264.7 cells and increase the productions of nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6). PSPs could also enhance phagocytic activity of RAW 264.7 cells. The acidic polysaccharide fractions of PSP-2, PSP-3, and PSP-L with small molecular weight had the higher immunostimulatory activity. Signaling pathway research results indicated that PSP-L activated RAW264.7 cells through MAPKs, NF-κB signaling pathways via TLR4 receptor.

The Effect of Cladode Drying Techniques on the Prebiotic Potential and Molecular Characteristics of the Mucilage Extracted from Opuntia ficus-indica and Opuntia joconostle

The dry, powdered cladodes of Opuntia ficus-indica are often-used in over-the-counter (OTC) pharmaceutical formulations. Gentle drying techniques, such as lyophilization and vacuum drying are compared with convection drying for the cladodes and also compared with another species of economic importance, Opuntia joconostle. The heteropolysaccharide purified from the mucilage extracted from the dried powders were investigated in their monosaccharide composition (HPAEC-PAD, TLC), mineral and protein content, molecular dimensions (SEC) and fermentability by probiotic bacteria (Bioscreen technique) for evaluation of the prebiotic potential of the mucilage. The heteropolysaccharide is composed of galactose, arabinose, xylose, galacturonic acid and rhamnose. O. ficus-indica includes an additional 13% of glucose coming from an α-glucan. The content of Ca (0.3%) and Mg (0.4%) is relatively low in both species; the content of protein adds up to 1.5% in O. ficus-indica but is significantly lower in O. joconostle with 0.8%. The average molecular mass Mw of the extracted mucilage ranges from 3.7 to 4.7 × 105 g∙mol−1 for both species; only the mucilage from long-time convection drying (C2) delivers a lower average Mw of 2.6 × 105 g∙mol−1, due to partial breakdown of the mucilage matrix. All tested probiotic strains utilized the mucilage to some extent; C2 being the most active, and thus confirms the prebiotic potential of cladode’s powder and its derived products. In general, the molecular dimensions and prebiotic potential are not extremely sensitive to the drying treatment, yet temperature and drying time can modify the cladode’s powder to a profile with better prebiotic characteristics.

Structural characterization and immunostimulatory activity of polysaccharides from Pyrus sinkiangensis Yu

Two neutral polysaccharides (PSNP-1, 104.7 kDa; PSNP-2, 24.5 kDa) were isolated from the pulp of Pyrus sinkiangensis Yu. by using the combined techniques of ion-exchange and gel permeation chromatography. According to the IR, NMR spectra, monosaccharide composition, and methylation analyses, PSNP-1 was mainly composed of glucose and xylose residues, which form a typical xyloglucan. PSNP-2 contained an arabinan region composed of 1,5-linked Araf residues, a xyloglucan region that was mainly composed of t-, 1,2-linked Xylp, and 1,4-, 1,4,6-linked Glcp residues. PSNP-1 and PSNP-2 could stimulate the cell viability, NO release, and cytokine secretion (IL-6 and TNF-α) of RAW264.7 macrophages at the adosage of 250 μg/mL. It was suggested that PSNP-1 and PSNP-2 may increase macrophage-mediated immunostimulatory activity.

Enhanced production and immunomodulatory activity of levan from the acetic acid bacterium, Tanticharoenia sakaeratensis

Levan is a fructose polymer with β-(2 → 6) glycosidic linkages. It is produced by several microorganisms, and due to its potential biotechnological and industrial applications, various levan-producing bacteria with different levels of production efficiencies have been reported. We investigated the levan-producing ability of the acetic acid bacterium, Tanticharoenia sakaeratensis. The exopolysaccharides produced by the bacterium under a sucrose environment were characterized as levan by FT-IR, and ¹H and ¹³C NMR. The molecular weight of levan thus produced range from 1.0 × 10⁵-6.8 × 10⁵ Da. The maximum yield of levan from T. sakaeratensis is 24.7 g·L^-1 in a liquid medium containing 20% (w/v) sucrose and incubated at 37 °C, 250 RPM for 35 h. The levan produced by T. sakaeratensis can promote nitric oxide production in RAW264.7 macrophage cells in a concentration-dependent manner, suggesting it has immunomodulatory effects. Our study reveals that T. sakaeratensis can be potentially employed as a new source of levan for industrial applications.

Polysaccharides from Opuntia milpa alta alleviate alloxan-induced INS-1 cells apoptosis via reducing oxidative stress and upregulating Nrf2 expression

The incidence and progression of type 2 diabetes are closely related to pancreatic β-cell damage. Oxidative stress may be one of the key factors contributing to β-cell apoptosis. Opuntia milpa alta polysaccharides (MAPs) are water-soluble macromolecular polysaccharides that have antidiabetic effects in vivo. Therefore, we hypothesized that MAPs might effectively prevent β-cell apoptosis via the inhibition of oxidative damages. In this study, INS-1 cells were exposed to alloxan with different concentrations of MAPs in vitro, and the cell viability, oxidative enzyme activities, nitric oxide production, reactive oxygen species production, apoptosis, and the expression of proteins in the antioxidant nucleus transcription factor NF-E2-related factor 2 (Nrf2) pathway and proteins related to apoptosis were measured to assess oxidative stress responses and apoptosis. The results indicated that INS-1 cell viabilities and superoxide dismutase and reduced glutathione activities were significantly restored, whereas lactate dehydrogenase releases and reactive oxygen species, nitric oxide, and malondialdehyde levels were greatly decreased after MAPs treatment. We found that MAPs could attenuate alloxan-induced apoptosis by increasing the expression of Bcl-2 and decreasing the expression of Bax and the activities of caspase-3 and caspase-9. The results of Western blot revealed that MAPs suppressed the expression of cleaved caspase-3 and cleaved PARP and upregulated the expression of nucleus Nrf2 and its downstream protein. These findings indicated that MAPs could alleviate alloxan-induced β-cell apoptosis by reducing oxidative stress and upregulating Nrf2 expression.

Structural characterization of novel comb-like branched α-d-glucan from Arca inflata and its immunoregulatory activities in vitro and in vivo

In the current study, we identified and characterized a novel water-soluble polysaccharide (JNY2PW) with significant immunoregulatory effects and no apparent overall toxicity. JNY2PW, which was isolated from Arca inflata, belongs to a novel class of α-glucans with a molecular weight of 5.25 × 107 Da. Its backbone is composed of (1 → 4)-linked α-d-glucopyranosyl residues and a single (1 → 6)-α-d-glucopyranosyl branched unit for every five α-d-glucopyranosyl residues, showing a comb-like α-d-glucan with intensive short branches. Using in vitro models, we demonstrated that JNY2PW exerts significant immunoregulatory effects by promoting the production of nitric oxide, interleukin-6, and tumor necrosis factor α. The pathway involves the activation of the TLR4-MAPK/NF-κB signaling cassette in murine RAW264.7 macrophages. In an in vivo immunosuppressive mice model induced by cyclophosphamide treatment, we found that the JNY2PW treatment produced good antitumor activity, comparable to that of chemotherapy by doxycycline in murine breast carcinoma 4T1-bearing mice, but devoid of any observable side effects (e.g. weight loss) related with doxycycline treatment. The anti-tumor mechanism of JNY2PW may involve an overall enhancement in the immune responses of the mice to tumors. These results indicate that JNY2PW possesses potential as an adjuvant to existing chemotherapy and current immune-oncology treatment.

Recent progress in the research of yam mucilage polysaccharides: Isolation, structure and bioactivities

Yam (Dioscorea spp.), known as an edible and medicinal tuber crop in China, has been used historically for the treatment of diabetes, diarrhea, asthma, and other ailments in traditional Chinese medicine. Moreover, it has been consumed as starchy food for thousands of years in China. Modern phytochemistry and pharmacological experiments have been proved that non-starch polysaccharide is one of the main bioactive substances of yam. Many studies have been focused on the isolation and identification of polysaccharides and their bioactivities of Chinese yam. However, due to the difference in the variety of raw materials and the method of polysaccharides extracting, the structure and biological activity of the obtained polysaccharides also differ. It has been demonstrated that Chinese yam polysaccharide has various important biological activities, such as hypoglycemia, immunomodulatory, antioxidant, and antitumor activities. This paper is aimed at summarizing previous and current references of the isolation processes, structural features and bioactivities of yam polysaccharides. The review will serve as a useful reference material for further investigation and application of yam polysaccharides in functional foods and medicine fields.

Structural characterization and in vitro-in vivo evaluation of effect of a polysaccharide from Sanguisorba officinalis on acute kidney injury

We report here an acidic polysaccharide, namely RSP-3, which ameliorates acute kidney injury and is obtained from Sanguisorba officinalis. We extracted and purified two polysaccharides from this herb based on the acidity and screened them for their effect in regulating the immunological activity of macrophages. Among them, RSP-3 exhibited significant anti-inflammatory activity against lipopolysaccharide (LPS)-stimulated macrophages by decreasing TNF-α and IL-6 levels. Subsequently, we found that RSP-3 suppressed ER stress, reduced ROS production and blocked NF-κBp65 translocation. After fully characterizing RSP-3 with a series of analytical technologies, we tested its anti-acute kidney injury (AKI) effect in vivo. In a murine AKI model induced by LPS, treatment with RSP-3 effectively ameliorated renal function. Besides, it decreased the levels of TNF-α and IL-6 in serum and reduced macrophage infiltration in injured kidney tissue. In sum, RSP-3, with a significant protective effect against AKI by showing anti-inflammatory activity, may become a meaningful drug candidate for treatment of AKI.