Current advances in the anti-inflammatory effects and mechanisms of natural polysaccharides

A review of pharmacological mechanisms, challenges and prospects of macromolecular glycopeptides

Macromolecular glycopeptides are natural products derived from various sources, distinguished by their structural diversity, multifaceted biological activities, and low toxicity. These compounds exhibit a wide range of biological functions, such as immunomodulation, antitumor effects, anti-inflammatory properties, antioxidant activity, and more. However, limited understanding of natural glycopeptides has hindered their development and practical application. To promote their advancement and utilization, it is crucial to thoroughly investigate the pharmacological mechanisms of glycopeptides and address the challenges in natural glycopeptide research. This review uniquely focuses on the primary biological activities and potential molecular mechanisms of glycopeptides as reported in recent literature. Moreover, we emphasize the current challenges in glycopeptide research, including extraction and isolation difficulties, purification challenges, structural analysis complexities, elucidation of structure-activity relationships, characterization of biosynthetic pathways, and ensuring bioavailability and stability. The future prospects for glycopeptide research are also explored. We argue that ongoing research into glycopeptides will significantly contribute to drug development and provide more effective therapeutic options and disease treatment alternatives for human health.

Polysaccharides with antioxidant activity: Extraction, beneficial roles, biological mechanisms, structure-function relationships, and future perspectives: A review

Polysaccharides are valuable macromolecules due to their multiple bioactivities, safety, and a wide range of sources. Recently, a series of polysaccharides with antioxidant activity have been intensively reported. In this review, the latest advances in polysaccharides with antioxidant activity have been reviewed, primarily based on the investigations of polysaccharides regarding advanced extraction methods, roles in oxidative stress-related diseases, intracellular signaling pathways associated with antioxidant responses, activating pathways in the gut, structure-function relationships, and methods to improve antioxidant activity. The summarized information highlighted that much work needs to be conducted, from laboratory to industry, to understand and fully utilize the antioxidant potential of polysaccharides. Finally, future perspectives, including scaling-up of advanced extraction methods, standardizing the protocols for assessing and screening polysaccharides, bridging gaps on the biological mechanisms underlying antioxidant activity, performing clinical trials, and elucidating structure-antioxidant relationships, have been addressed. The information present in this review will be helpful to the scientific community when studying on polysaccharides with antioxidant potential and provides research directions for a better understanding of the polysaccharides and promotes their successful applications in functional foods and nutraceuticals.

Exopolysaccharide of Levilactobacillus brevis M-10 Improved Physiological and Biochemical Indicators and Gut Microbiota in DSS-Induced Colitis Mice

Ulcerative colitis (UC) is a typical type of inflammatory bowel disease, which is often recurrent and directly related with colorectal cancer. Therefore, early prevention and treatment for UC is very necessary. Therefore, it is necessary to find efficient substances to treat the UC with less side effects than drugs. Exopolysaccharides (EPSs) are important bioactive constituents of lactic acid bacteria. The study evaluated the effects of EPS1 produced by Levilactobacillus brevis M-10 on UC by determining the weight, the disease activity index (DAI) and the physiological and biochemical indexes. The pathological structures of colon were observed. The gut microbiota and the short-chain fatty acids were analyzed. The results demonstrated high dose (HD) of EPS1 (400 mg/kg-BW) that had the best effects on UC mice. The HD group restored body weight, decreased DAI and alleviated shortening of the length of the colon, recovered liver tissue, declined lipopolysaccharide, and myeloperoxidase. Also the HD group showed that the expression of tight junction proteins increased, IL-10 up-regulated, IL-6, IL-1β, and TNF-α down-regulated, and the gut microbiota dysbiosis balanced. The HD group markedly elevated the relative abundance of Lachnospiraceae_NK4A136_group, Unclassified-Lachnospiraceae, and Unclassified- Muribaculaceae. Acetic acid, propionic acid, and n-butyric acid were significantly increased in the HD group (P < 0.05). The study could provide a theoretical basis and material support for the exploration of safe functional food in alleviating and preventing UC.

Calcium-ion-driving assembly of polysaccharide deriving from Zizyphus jujuba to hemostatic hydrogel for treating diabetic wound

Due to good biocompatibility and biodegradable, natural polysaccharide-based hydrogels have received worldwide attentions, where polysaccharide polymers were usually chemically modified to meet the specific elastic requirements. However, it remained highly challenging to develop polysaccharide-based hydrogels with desired mechanical properties and biological functions devoid of any structural modifications. Herein, with the coordination of Ca2+ (15.0 mM), the jujuba polysaccharide (JPS, 1 %) was facilely fabricated to a hydrogel (JPS-gel) within 1 min at pH 10, where the residual proteins also played crucial roles on the assembly. The JPS-gel showed outstanding stability and mechanical properties, which were tunable by adjusting the content of Ca2+/JPS. The JPS-gel also revealed excellent biocompatibility, and could expedite the migration and proliferation of healing-related cells, angiogenesis and alleviate inflammation response. More interestingly, the JPS-gel had hemostatic capacity, where the hemostatic time and blood loss in liver incision model were 13 ± 3 s and 6.3 ± 1.6 mg after 120 s treatment with JPS-gel, respectively. All these superiorities endowed JPS-gel high performance healing in diabetic wounds (10 days). Specially, the expressions of inflammation-related genes were downregulated, but gene expressions associated with cell migration and proliferation, and angiogenesis were upregulated, thus uncovering the action mechanism of JPS-gel on accelerating wound contraction.

Structure characterization and preliminary immune activity of a glucomannan purified from Allii Tuberosi Semen

A novel glucomannan, named ATSW-1, was obtained from Allii Tuberosi Semen by ion and gel permeation chromatography purification. Its structure was characterized using high-performance chromatography, Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry, and nuclear magnetic resonance spectroscopy. The in vitro immune activities of ATSW-1 were examined using the Cell Counting Kit-8, the neutral red phagocytosis assay, and the secretion of related cytokines. The results showed that the molecular weight of ATSW-1 was 35.9 kDa and mainly constituted of mannose, glucose, and arabinose with a molar ratio of 1:0.72:0.04. Its main backbone was composed of →4)-β-D-Glcp-(1→, →4)-β-D-Manp-(1→, and →4,6)-α-D-Manp-(1→, with the branches β-D-Glcp-(1→, α-L-Araf-(1→ and →5)-α-L-Araf-(1→ linkage substituted at C-6 position of →4)-α-D-Manp-(1 → . ATSW-1 significantly enhanced immune responses, increasing the phagocytic activity of RAW264.7 cells by 1.52 times compared to the blank control group. Further investigations revealed that ATSW-1 promotes immune activity by upregulating the NO, TNF-α, and IL-6 secretion. These findings provide a foundation for the potential development and application of Allii Tuberosi Semen polysaccharides in functional foods or immune-related therapeutics.

Cordycepin attenuates NLRP3/Caspase-1/GSDMD-mediated LPS-induced macrophage pyroptosis

Pyroptosis, a form of programmed cell death driven by the NLRP3 inflammasome, is a key contributor to inflammation in various diseases. This study aimed to investigate the anti-inflammatory mechanisms of cordycepin, focusing on its role in macrophage pyroptosis. Molecular docking analysis was performed to evaluate the binding affinity of cordycepin to key pyroptosis-related proteins, including NLRP3, Caspase-1, and GSDMD. RAW264.7 cells were pre-treated with cordycepin to assess its effects on pyroptosis. Key measurements included reactive oxygen species (ROS) levels, xanthine oxidase (XO) activity, and the expression of NLRP3, Caspase-1, and GSDMD. Additionally, lactate dehydrogenase (LDH) release, interleukin (IL)-1β and IL-18 levels in the culture supernatant, and macrophage cell death rates were evaluated using Hoechst 33342/PI dual staining. The results demonstrated that cordycepin exhibits strong binding affinity for NLRP3, Caspase-1, and GSDMD. Cordycepin pre-treatment significantly reduced ROS levels and XO activity, inhibited the expression of NLRP3, cleaved-Caspase-1, and cleaved-GSDMD, and decreased pyroptosis-associated inflammatory cytokines IL-1β and IL-18, along with Caspase-1 activity. Furthermore, cordycepin reduced the macrophage pyroptosis rate. In conclusion, cordycepin inhibits macrophage pyroptosis by reducing XO activity, suppressing ROS production, and regulating the expression of key molecules in the NLRP3/Caspase-1/GSDMD pathway. These findings provide a strong experimental basis for the potential development of cordycepin as a novel anti-inflammatory agent.

Chemical Fingerprinting, Anti-Inflammatory, and Antioxidant Potential of Hydroethanolic Extract of Aesculus indica

Aesculus indica is a remarkable species from Sapindaceae family, traditionally used for the treatment of various ailments due to the presence of a variety of bioactive compounds. The present study was planned to evaluate the chemical characterization, anti-inflammatory and antioxidant potential of hydroethanolic extract of A. indica using in vitro and in vivo approaches. A. indica fruit was extracted with a hydroethanolic (70% v/v) solution, filtered, concentrated on a rotary evaporator and crude extract was obtained. In vitro anti-inflammatory potential of A. indica was carried out against peripheral blood mononuclear cells (PBMCs) and a whole blood assay (WBA). Effects of A. indica extracts on proinflammatory cytokines (TNF-α, IFN-gamma, IL-6, IL-1β) and inflammatory mediators (NF-κB, NO and PGE2) concentration in the supernatant of PBMCs and WBA were evaluated using commercial ELISA kits. In vivo anti-inflammatory potential of A. indica hydroethanolic extract was evaluated with carrageenan-induced paw edema in rats. A total of 36 different compounds (mostly phenolics) were detected in A. indica extract with high performance liquid chromatography (HPLC) and UHPCL-QTOF-MS/MS. The extract showed very low cytotoxicity with an IC50 value of 483.68 μg/mL and significantly reduced the levels of proinflammatory cytokines and inflammatory mediators in both PBMCs and WBA models. Furthermore, the extract also effectively inhibited the paw edema by carrageenan in the 2nd hour at 400 mg/kg (73%). Histopathological analysis of rat paw tissue showed significant reduction of cellular infiltration and decrease in swelling of epidermis and dermis by A. indica extracts. The level of enzymatic antioxidants such as superoxide dismutase (SOD) and Catalase (CAT), lipid peroxidation like malondialdehyde (MDA), oxidative stress parameters including total antioxidant status (TAS) and total oxidant status (TOS) and myeloperoxidase (MPO) activity in rat paw tissues were significantly altered after treatment. The combined findings provide evidence that hydroethanolic extract of A. indica is a potential source of bioactive compounds with significant anti-inflammatory and antioxidant activities.

Transcriptomics and metabolomics reveal the alleviation effect of pectic polysaccharide on dextran sodium sulfate-induced colitis mice

Ulcerative colitis (UC) is a relapsing disease with an increasing morbidity and prevalence. Dietary polysaccharides have recently become a research hotspot because of their therapeutic effects and safety on UC. Our previous research elucidated that pectic polysaccharide from Phyllanthus emblica L. (PEP-1) could alleviate dextran sodium sulfate-induced UC mice. Herein, metabolomics and transcriptomics were further applied to disclose the underlying mechanisms behind PEP-1's anti-inflammatory effects. PEP-1 intervention altered the serum metabolite contents and pathways represented by decreasing xanthine and sphinganine levels. Changes in gene expressions correlated with metabolite variations led by the suppression of the expression of the inflammatory factors, colorectal cancer promoter, and NF-κB pathway as well as the enhancement of tight junctions. This study demonstrated that the ameliorating effect of chronic UC was partially ascribed to the alteration of the serum metabolites and changes in gene expression.

Sulfated Pelvetia siliquosa Polysaccharides Inhibit CaOx Stone Formation by Inhibiting Calcium Oxalate Crystallization, Cellular Inflammation, and Crystal Adhesion

Hyperoxaluria can easily induce calcium oxalate (CaOx) crystals and cause cell damage, thereby increasing the risk of kidney stone formation. In this study, three sulfated Pelvetia siliquosa polysaccharides (PSPs) were obtained by the sulfur trioxide-pyridine method. The antioxidant activity of PSPs and the inhibitory effects of PSPs on CaOx crystallization, cellular oxidative damage, and cellular inflammation were explored in vitro, and PSPs were used to treat hyperoxaluria-induced crystallization model mice in order to validate the stone-preventive effect of PSPs in vivo. PSPs can inhibit CaOx crystal formation, as well as reduce reactive oxygen species (ROS) levels through their own antioxidant properties and up-regulation of antioxidant enzyme (SOD and CAT) expression, which in turn reduces the release of lactate dehydrogenase (LDH) and malondialdehyde (MDA), improves lysosomal integrity, cellular morphology, and cytoskeleton, inhibits the decrease of mitochondrial membrane potential, reduces adhesion protein (CD44 and OPN) expression, alleviates cellular inflammatory factor (IL-6, TNF-α, and IL-1β) levels, and inhibits apoptosis. PSP3, which has the highest degree of sulfation, had the best protection capacity. PSP3 also showed good antistone ability in mice, and it may be a potential drug for kidney stone prevention.

Effects of microbial fermentation on the anti-inflammatory activity of Chinese yam polysaccharides

In this study, Chinese yam polysaccharides (CYPs) were fermented using Lactobacillus plantarum M616, and changes in the chemical composition, structure, and anti-inflammatory activity of CYPs before and after fermentation were investigated. The carbohydrate content of L. plantarum M616-fermented CYP (CYP-LP) increased from 71.03% ± 2.75 to 76.28% ± 2.37%, whereas protein and polyphenol content were almost unaffected compared with those of the unfermented CYP (CYP-NF). The monosaccharide composition of CYP-NF included rhamnose, arabinose, galactose, glucose, and mannose in a molar ratio of 0.493:0.6695:0.9738:0.7655:12.4365. CYP-LP had the same monosaccharides as CYP-NF, but the molar ratio was 0.3237:0.3457:0.8278:2.5541:10.4995. Meanwhile, the molecular weight and polydispersity of CYP-LP, respectively, increased from 124.774 kDa and 6.58 (CYP-NF) to 376.628 kDa and 17.928, indicating a low homogeneity. In vitro antioxidant analysis showed that L. plantarum M616 fermentation had varying effects on CYP-LP against DPPH, ABTS, hydroxyl, and superoxide radicals. However, CYP-LP had superior anti-inflammatory activity to CYP-NF and is more effective in regulating superoxide dismutase, catalase, glutathione peroxidase, malondialdehyde, nitric oxide, tumor necrosis factor-α, interleukin-1β, and interleukin-6 release in lipopolysaccharide-induced RAW 264.7 macrophages. This study suggested that CYP-LP is a potential anti-inflammatory ingredient in drugs and functional food.

Chick Early Amniotic Fluid Alleviates Dextran-Sulfate-Sodium-Induced Colitis in Mice via T-Cell Receptor Pathway

Ulcerative colitis (UC) is a chronic immune disease that is difficult to cure. We recently found that chick early amniotic fluid (ceAF) has notable anti-inflammatory and antioxidative properties, through its active components. This study demonstrates the potential of ceAF as a protective agent against UC. UPLC-MS mass spectrometry identified key components of ceAF, including various fatty acids and nucleosides. In vitro, ceAF improved viability in DSS-induced Caco-2 cells, reduced pro-inflammatory cytokines IL-1β and TNF-α, and increased the anti-inflammatory cytokine IL-10. It also upregulated the tight junction proteins ZO-1 and occludin. In DSS-induced UC mice, ceAF treatment alleviated weight loss, colon shortening, and disease activity, while improving histopathology, crypt depth, and colonic fibrosis. Mechanistically, ceAF's anti-inflammatory effects are mediated by inhibiting the overactivation of TCR signaling through the LCK/ZAP70/LAT pathway. Our findings suggest that ceAF could be a valuable nutritional intervention for UC, potentially enhancing existing functional foods aimed at managing this condition.

Cordyceps militaris-Derived Bioactive Gels: Therapeutic and Anti-Aging Applications in Dermatology

Cordyceps militaris is a medicinal mushroom widely utilized in traditional East Asian medicine, recognized for its diverse therapeutic properties. This review explores the potential of C. militaris-derived bioactive gels for applications in dermatology and skincare, with a particular focus on their therapeutic and anti-aging benefits. In response to the rising incidence of skin cancers and the growing demand for natural bioactive ingredients, C. militaris has emerged as a valuable source of functional compounds, including cordycepin, polysaccharides, and adenosine. These compounds exhibit multiple bioactivities, including apoptosis induction, cell cycle arrest, and anti-inflammatory effects, which have been shown to be particularly effective against melanoma and other skin cancers. Additionally, the antioxidant properties of C. militaris enhance skin resilience by scavenging reactive oxygen species, reducing oxidative stress, and promoting collagen synthesis, thereby addressing skin health and anti-aging requirements. The potential for incorporating C. militaris compounds into gel-based formulations for skincare is also examined, either as standalone bioactives or in combination with synergistic ingredients. Emphasis is placed on the necessity of clinical trials and standardization to establish the safety, efficacy, and reproducibility of such applications. By providing a safer alternative to synthetic agents, C. militaris-derived bioactive gels represent a promising advancement in dermatology and skincare.

Comparison of polysaccharides from stem barks and flowers of Magnolia officinalis: Compositional characterization, hypoglycemic and photoprotection activities

The extraction of polysaccharides from stem barks and flowers of Magnolia officinalis were optimized using response surface methodology and the maximum yields were 4.12 ± 0.06 % and 5.5 ± 0.08 %, respectively. Three homogeneous polysaccharides including MOBP-I, MOBP-II and MOFP-I were further purified and their compositional characterization were compared. Molecular weights of MOBP-I, MOBP-II and MOFP-I were 5.9 × 103, 6.8 × 103 and 3.9 × 104 Da, respectively. Gas chromatography (GC) analysis suggested that MOBP-I, MOBP-II and MOFP-I were composed of rhamnose, arabinose, mannose, glucose and galactose at different ratios and exhibited different appearance and glycosidic linkages. MOFP-I but not MOBP-I and MOBP-II had three helix structures. MOBP-I, MOBP-II and MOFP-I showed significant hypoglycemic and photoprotection capacities with different efficacy. MOBP-I had greater hypoglycemic activity, as evidenced by the increased α-glucosidase inhibition activity and glucose consumption in insulin-resistant HepG2 cells. MOBP-II and MOFP-I were more powerful in reversing ultraviolet-B (UVB)-irradiated photoaging of HaCaT cells. The difference of polysaccharides compositions might explain for their bioactivity discrepancy.

A fructan-type garlic polysaccharide upregulates immune responses in macrophage cells and in immunosuppressive mice

The anti-inflammatory effects of plant polysaccharides are well known. However, the stimulatory effects of polysaccharides under immunosuppressive conditions and their link with the polysaccharide structure is underexplored. In this work, the immune modulatory effects of a garlic polysaccharide (GP) are investigated via in vitro and vivo methods. It is observed that GP enhance the immune response of macrophages (RAW264.7) as indicated by the elevated levels of nitric oxide, TNF-α and IL-6. The observation that GP are able to stimulate the immune response in vitro was then explored with the use of an immunosuppressed mouse model. Surprisingly, GP exhibited dose-dependent up-regulatory impacts on the cyclophosphamide (CTX) suppressed levels of cytokines such as IFN-γ and IL-6 and immunoglobulins (e.g. IgA and IgG). The GP intervention reversed histopathological damage to the small intestine and spleen and increased fecal short-chain fatty acid levels. Moreover, GP modulates the gut microbiota dysbiosis by increasing the abundance of immunogenic bacteria such as g__norank_f__Erysipelotrichaceae, while inhibiting the over-abundance of g_Bacteroides. Functional predictions indicated that gut biomarkers of GP possessed the functions of glycoside hydrolase family 32 (GH32) and β-fructofuranosidase. It is concluded that GP is a promising immunostimulant for immune-compromised individuals.

Yeast β-glucan attenuates dextran sulfate sodium-induced colitis: Involvement of gut microbiota and short-chain fatty acids

Yeast β-glucan intervention offers a promising strategy for managing colitis; however, the mechanisms remain unknown. In the present work, the protective effects of yeast β-glucan on DSS-induced colitis in mice was evaluated, focusing on its interaction with gut microbiota. The result showed yeast β-glucan significantly alleviated colitis symptoms, evidenced by reduced weight loss, lower disease activity index (DAI) scores, and minimized intestinal damage. It enhanced intestinal barrier integrity via upregulation of tight junction proteins, suppressed lipopolysaccharide (LPS) release, and decreased pro-inflammatory cytokines production. Additionally, yeast β-glucan boosted short-chain fatty acids (SCFAs) production, and activated their receptors, increased the relative abundances of beneficial microbes like Lactobacillus and Lachnospiraceae_UCG-006. Transcriptomic analyses suggest that yeast β-glucan mitigates inflammation by downregulating gene expression related to IL-17 pathway. Our findings highlight potential of yeast β-glucan as a therapeutic agent for colitis through modulation of gut microbiota and inflammatory responses.

One-step construction of silver nanoparticles immersed hydrogels by triple-helix β-glucans and the application in infectious wound healing

Hydrogels composed of polysaccharides and silver nanoparticles (AgNPs) are widely recognized for their applications in wound dressings, particularly for healing wounds prone to infection. Traditional methods for preparing AgNPs immersed hydrogels are often complex, costly, and may lead to sustained cytotoxicity. To address these challenges, we developed a biocompatible, one-step green reduction strategy to generate AgNPs within hydrogels using a triple-helix β-glucan (PCPA) derived from Poria cocos, a renowned Chinese traditional herb. PCPA serves as a reducing agent, converting silver ions into AgNPs while its triple-helix conformation prevents AgNPs aggregation. The resulting hydrogel (PAg-G) is injectable and contains uniformly distributed AgNPs. PAg-G exhibits broad-spectrum antimicrobial activity and enhanced bioactivity. The in vivo study on S.aureus-infected SD rats demonstrated that PAg-G can accelerate wound healing within 12 days by down-regulating inflammatory factors such as IL-6 and TNF-α, and up-regulating VEGF and CD31 expression, promoting neovascularization in wound tissues. This innovative one-step construction of AgNPs immersed hydrogels offers a promising approach for the development of antimicrobial hydrogels, especially for treating bacterial-infected wounds.

Artemisia Ordosica Polysaccharides Enhance Antioxidant Capacity of Peripheral Blood Lymphocytes in Poultry Through Nrf2/Keap1 and TLR4/NF-κB Signal Pathway

Artemisia ordosica polysaccharides (AOP) can promote animal growth, improve intestinal morphology, regulate immunity, and enhance antioxidant capacity. To investigate the antioxidant capacity of AOP, three experiments were conducted. (1) Different concentrations of AOP (0, 50, 100, 150, 200, and 250 μg/mL) and 1 µg/mL VA on peripheral blood lymphocytes (PBLs) treated with/without lipopolysaccharides (LPS) were investigated to select the optimum concentration. The results showed that 150 μg/mL AOP had significant antioxidation activity. (2) The PBLs was randomly divided into eight treatments with six replicates, namely CON, AOP, LPS, ML385 (Nrf2 inhibitor), AOP + LPS, AOP + ML385, LPS + ML385 and LPS + ML385 + AOP. The results showed that under a normal condition or stress condition, AOP presented antioxidation activity via upregulating Nrf2/Keap1 pathway-related gene expression. (3) The PBLs was randomly divided into eight treatments with six replicates, namely CON, AOP, LPS, PDTC (NF-κB inhibitor), AOP + LPS, AOP + PDTC, LPS + PDTC and LPS + PDTC + AOP. The results showed that under a normal condition, AOP presented antioxidation activity via increasing TLR4/NF-κB pathway-related gene expression; under a stress condition, AOP alleviated oxidative damage caused by LPS via suppressing TLR4/NF-κB pathway-related gene expression.

Research Progress on the Biological Activity of Ganoderic Acids in Ganoderma lucidum over the Last Five Years

Ganoderma lucidum (G. lucidum) is a traditional edible and medicinal mushroom in China. The main bioactive components in G. lucidum include triterpenoids, polysaccharides, steroids, and sterols. Ganoderic acids (GAs) are one of the most abundant triterpenoids found in G. lucidum, garnering significant attention from researchers in the fields of medicine and health care. We summarize the extensive studies on the physiological function of GAs in anti-cancer, anti-inflammatory, radiation protection, anti-aging, liver protection, anti-microbial, and neuroprotection areas, among others. This review provides a comprehensive overview of the recent advances in the bioactivities and pharmacological mechanisms of GAs, aiming to delineate the current research directions and the state of the art in this field. This analysis helps to rapidly identify new bioactivities of GAs and understand their mechanisms, leading to more effective treatments for various diseases.

Abelmoschi Corolla polysaccharides and related metabolite ameliorates colitis via modulating gut microbiota and regulating the FXR/STAT3 signaling pathway

Ulcerative Colitis (UC) is a chronic inflammatory disease of the intestinal tract with unknown definitive etiology. Polysaccharides are among the most important active components of Abelmoschi Corolla, exhibitings various pharmacological activities such as antioxidation and immunomodulation. However, no studies have yet reported the application of Abelmoschi Corolla Polysaccharides (ACP) in treating UC. This study aims to highlight the therapeutic efficacy of ACP in UC and reveal the underlying mechanism. The potential therapeutic effect is initially verified using a dextran sodium sulfate (DSS)-induced colitis model. 16S rRNA sequencing is performed using feces samples and untargeted metabolomics using serum samples to further reveal that ACP reprograms the dysbiosis triggered by UC progression, increases the abundance of Bacteroides spp., Blautia spp., and Parabacteroides spp. at the genus level and enriches the serum concentration of 7-ketodeoxycholic acid (7-KDA). Furthermore, using the FXR-/- mouse model, it is revealed that Farnesoid X Receptor (FXR) is a key target for ACP and the metabolite 7-KDA to block STAT3 phosphorylation by repairing the intestinal barrier to attenuate UC. Taken together, this work highlights the therapeutic potential of ACP against UC, mainly exerting its effects via modulating gut microbiota and regulating the FXR/STAT3 signaling pathway.

Advance in Cistanche deserticola Y. C. Ma. polysaccharides: Isolation, structural characterization, bioactivities and application: A review

Cistanche deserticola Y. C. Ma (CD), is mainly distributed in the regions of China (Xinjiang, Inner Mongolia, Gansu), Mongolia, Iran and India. Cistanche deserticola polysaccharide (CDPs), as one of the main components and a crucial bioactive substance of CD, has a variety of pharmacological activities, including immunomodulatory, anti-aging, anti-oxidant, hepatoprotective, anti-osteoporotic, anti-inflammatory, intestinal flora regulatory effects. Many polysaccharides have been successfully obtained in the last three decades from CD. However, there is currently no comprehensive review available concerning CDPs. Considering the importance of CDPs for biological study and drug discovery, the present review aims to systematically summarize the recent major studies on extraction and purification methods of polysaccharides from CD, as well as the characterization of their chemical structure, biological activity, structure-activity relationship, and the application of CDPs in pharmaceutical field. Meanwhile, the shortcomings of CDPs research are further discussed in detail, and new valuable insights for future CDPs research as therapeutic agents and functional foods are proposed.

Effects of polysaccharide from Pueraria lobata on osteoarthritis in rats

The effects of Pueraria lobata polysaccharide (PPL-1) on osteoarthritis (OA) disease were comprehensively evaluated by using chondrocytes and synoviocytes extracted from the joints of SD rats based on in vitro cell experiments and by establishing pathological models of OA rats. The results showed that concentrations of 1.25-10 and 0.2-1.6 μg/mL, PPL-1 did not inhibit or promote chondrocytes and synoviocytes in vitro. However, at concentrations of 1.25-10 and 0.2-1.6 μg/mL, it can promote cartilage and synovial membrane cells after LPS stimulation of cell activity and inhibite LPS-induced apoptosis. The results of animal experiments showed that PPL-1 can reduce the symptoms of joint swelling in OA rats, decrease the production of serum inflammatory cytokines TNF-α, IL-1β, and IL-6, and slow down the occurrence of inflammation. Therefore, from the perspective of symptoms, inflammatory factors and pathology, PPL-1 has therapeutic effects on OA rats and alleviates the development of inflammation. It indicated that PPL-1 has the potential to be developed into an OA therapeutic drug with anti-inflammatory properties that protects and activates chondrocytes.

Abelmoschus manihot polysaccharide fortifies intestinal mucus barrier to alleviate intestinal inflammation by modulating Akkermansia muciniphila abundance

The intestinal mucus barrier is an important line of defense against gut pathogens. Damage to this barrier brings bacteria into close contact with the epithelium, leading to intestinal inflammation. Therefore, its restoration is a promising strategy for alleviating intestinal inflammation. This study showed that Abelmoschus manihot polysaccharide (AMP) fortifies the intestinal mucus barrier by increasing mucus production, which plays a crucial role in the AMP-mediated amelioration of colitis. IL-10-deficient mouse models demonstrated that the effect of AMP on mucus production is dependent on IL-10. Moreover, bacterial depletion and replenishment confirmed that the effects of AMP on IL-10 secretion and mucus production were mediated by Akkermansia muciniphila. These findings suggest that plant polysaccharides fortify the intestinal mucus barrier by maintaining homeostasis in the gut microbiota. This demonstrates that targeting mucus barrier is a promising strategy for treating intestinal inflammation.

Interactions between Gut Microbiota and Natural Bioactive Polysaccharides in Metabolic Diseases: Review

The gut microbiota constitutes a complex ecosystem, comprising trillions of microbes that have co-evolved with their host over hundreds of millions of years. Over the past decade, a growing body of knowledge has underscored the intricate connections among diet, gut microbiota, and human health. Bioactive polysaccharides (BPs) from natural sources like medicinal plants, seaweeds, and fungi have diverse biological functions including antioxidant, immunoregulatory, and metabolic activities. Their effects are closely tied to the gut microbiota, which metabolizes BPs into health-influencing compounds. Understanding how BPs and gut microbiota interact is critical for harnessing their potential health benefits. This review provides an overview of the human gut microbiota, focusing on its role in metabolic diseases like obesity, type II diabetes mellitus, non-alcoholic fatty liver disease, and cardiovascular diseases. It explores the basic characteristics of several BPs and their impact on gut microbiota. Given their significance for human health, we summarize the biological functions of these BPs, particularly in terms of immunoregulatory activities, blood sugar, and hypolipidemic effect, thus providing a valuable reference for understanding the potential benefits of natural BPs in treating metabolic diseases. These properties make BPs promising agents for preventing and treating metabolic diseases. The comprehensive understanding of the mechanisms by which BPs exert their effects through gut microbiota opens new avenues for developing targeted therapies to improve metabolic health.

Polysaccharide hydrogels for skin wound healing

Advances in the development and utilization of polysaccharide materials are highly promising, offering prominent applications in the field of tissue engineering for addressing diverse clinical needs, including wound healing, bone regeneration, cartilage repair, and treatment of conditions such as arthritis. Novel polysaccharide materials are popular owing to their inherent stability, biocompatibility, and repeatability. This review presents an overview of the biomedical applications of natural polysaccharide hydrogels and their derivatives. Herein, we discuss the latest advancements in the fabrication, physicochemical properties, and biomedical applications of polysaccharide-based hydrogels, including chitosan, hyaluronic acid, alginate, and cellulose. Various processing techniques applicable to polysaccharide materials are explored, such as the transformation of polysaccharide hydrogels into electrospun nanofibers, microneedles, microspheres, and nanogels. Furthermore, the use of polysaccharide hydrogels in the context of wound-healing applications, including hemostatic effects, antimicrobial activities, anti-inflammatory properties, and promotion of angiogenesis, is presented. Finally, we address the challenges encountered in the development of polysaccharide hydrogels and outline the potential prospects in this evolving field.

The prophylaxis functions of Lactobacillus fermentum GLF-217 and Lactobacillus plantarum FLP-215 on ulcerative colitis via modulating gut microbiota of mice

BACKGROUND

The strong connection between gut microbes and human health has been confirmed by an increasing number of studies. Although probiotics have been found to relieve ulcerative colitis, the mechanism varies by the species involved. In this study, the physiological, immune and pathological factors of mice were measured and shotgun metagenomic sequencing was conducted to investigate the potential mechanisms in preventing ulcerative colitis.

RESULTS

The results demonstrated that ingestion of Lactobacillus fermentum GLF-217 and Lactobacillus plantarum FLP-215 significantly alleviated ulcerative colitis induced by dextran sulfate sodium (DSS), as evidenced by the increase in body weight, food intake, water intake and colon length as well as the decrease in disease activity index, histopathological score and inflammatory factor. Both strains not only improved intestinal mucosa by increasing mucin-2 and zonula occludens-1, but also improved the immune system response by elevating interleukin-10 levels and decreasing the levels of interleukin-1β, interleukin-6, tumor necrosis factor-α and interferon-γ. Moreover, L. fermentum GLF-217 and L. plantarum FLP-215 play a role in preventing DSS-induced colitis by regulating the structure of gut microbiota and promoting the formation of short-chain fatty acids.

CONCLUSIONS

This study may provide a reference for the prevention strategy of ulcerative colitis. © 2024 Society of Chemical Industry.

In vitro colon fermentation behaviors of Ca2+ cross-linked guluronic acid block from sodium alginate

The degradation of sodium alginate by human gut microbiota was found to be retarded via calcium cross-linking in our previous study. We hypothesized that the guluronic acid block (GB) on the alginate molecule might be the key structural region affecting alginate degradation by the gut microbiota when cross-linked with calcium. This study aims to prove this hypothesis by studying the structural features of the cross-linked GB on its in vitro fecal fermentation behaviors concerning the aspects of total carbohydrate contents, monosaccharide contents, short-chain fatty acids production, calcium state variations, and structural variations. Herein, GB isolated from sodium alginate was cross-linked under ranges of molar ratios of [Ca2+]/[-COOH] that further restricted the degradation by gut microbiota similar to the cross-linked alginates. First, total carbohydrate contents, short-chain fatty acids production, monosaccharides contents, and calcium state analyses confirmed that the degradation of GB by gut microbiota was restricted by calcium cross-linking. Furthermore, the tracking analysis of structural variations during in vitro fermentation revealed that the "granules" structure could further restrict degradation by the gut microbiota, leaving more cross-linked GB fragments surviving in comparison to the "networks" structure. In addition, Bacteroides xylanisolvens showed a significant positive correlation to the "cross-linking porosity (R = 0.825, p < 0.001), which supported our previous findings on fermentation behaviors of cross-linked alginate. Together, guluronic acid blocks are the key structural regions that retard the degradation of sodium alginate by the gut microbiota when cross-linked with calcium.

Recent progress in Porphyra haitanensis polysaccharides: Extraction, purification, structural insights, and their impact on gastrointestinal health and oxidative stress management

Porphyra haitanensis, a red seaweed species, represents a bountiful and sustainable marine resource. P. haitanensis polysaccharide (PHP), has garnered considerable attention for its numerous health benefits. However, the comprehensive utilization of PHP on an industrial scale has been limited by the lack of comprehensive information. In this review, we endeavor to discuss and summarize recent advancements in PHP extraction, purification, and characterization. We emphasize the multifaceted mechanisms through which PHP promotes gastrointestinal health. Furthermore, we present a summary of compelling evidence supporting PHP's protective role against oxidative stress. This includes its demonstrated potent antioxidant properties, its ability to neutralize free radicals, and its capacity to enhance the activity of antioxidant enzymes. The information presented here also lays the theoretical groundwork for future research into the structural and functional aspects of PHP, as well as its potential applications in functional foods.

Hybrid Double-Sided Tape with Asymmetrical Adhesion and Burst Pressure Tolerance for Abdominal Injury Treatment

Patients with open abdominal (OA) wounds have a mortality risk of up to 30%, and the resulting disabilities would have profound effects on patients. Here, we present a novel double-sided adhesive tape developed for the management of OA wounds. The tape features an asymmetrical structure and employs an acellular dermal matrix (ADM) with asymmetric wettability as a scaffold. It is constructed by integrating a tissue-adhesive hydrogel composed of polydopamine (pDA), quaternary ammonium chitosan (QCS), and acrylic acid cross-linking onto the bottom side of the ADM. Following surface modification with pDA, the ADM would exhibit characteristics resistant to bacterial adhesion. Furthermore, the presence of a developed hydrogel ensures that the tape not only possesses tissue adhesiveness and noninvasive peelability but also effectively mitigates damage caused by oxidative stress. Besides, the ADM inherits the strength of the skin, imparting high burst pressure tolerance to the tape. Based on these remarkable attributes, we demonstrate that this double-sided (D-S) tape facilitates the repair of OA wounds, mitigates damage to exposed intestinal tubes, and reduces the risk of intestinal fistulae and complications. Additionally, the D-S tape is equally applicable to treating other abdominal injuries, such as gastric perforations. It effectively seals the perforation, promotes injury repair, and prevents the formation of postoperative adhesions. These notable features indicate that the presented double-sided tape holds significant potential value in the biomedical field.

The regulatory effect of polysaccharides on the gut microbiota and their effect on human health: A review

Polysaccharides with low toxicity and high biological activities are a kind of biological macromolecule. Recently, growing studies have confirmed that polysaccharides could improve obesity, diabetes, tumors, inflammatory bowel disease, hyperlipidemia, diarrhea, and liver-related diseases by changing the intestinal micro-environment. Moreover, polysaccharides could promote human health by regulating gut microbiota, enhancing production of short-chain fatty acids (SCFAs), improving intestinal mucosal barrier, regulating lipid metabolism, and activating specific signaling pathways. Notably, the biological activities of polysaccharides are closely related to their molecular weight, monosaccharide composition, glycosidic bond types, and regulation of gut microbiota. The intestinal microbiota can secrete glycoside hydrolases, lyases, and esterases to break down polysaccharides chains and generate monosaccharides, thereby promoting their absorption and utilization. The degradation of polysaccharides can produce SCFAs, further regulating the proportion of gut microbiota and achieving the effect of preventing and treating various diseases. This review aims to summarize the latest studies: 1) effect of polysaccharides structures on intestinal flora; 2) regulatory effect of polysaccharides on gut microbiota; 3) effects of polysaccharides on gut microbe-mediated diseases; 4) regulation of gut microbiota on polysaccharides metabolism. The findings are expected to provide important information for the development of polysaccharides and the treatment of diseases.

Structural characterization and anti-inflammatory activities of a purified polysaccharide from fruits remnants of Alpinia zerumbet (Pers.) Burtt. et Smith

We reported here an interesting source of Alpinia zerumbet Polysaccharides (named AZPs) from the residues after extracting essential oil by steam distillation from Alpinia zerumbet fructus. After a series of purifications, a homogeneous polysaccharide (AZP-2) of molecular weight 1.25 × 105 Da was obtained. Structure, anti-inflammatory activity, and anti-inflammatory mechanism were investigated. AZP-2 was mainly composed of galactose, arabinose, xylopyranose, glucose, and galacturonic acid. The main linkage structure of AZP-2 was determined after integrating the nuclear magnetic resonance (NMR) and methylation analysis, and the structure was comparatively complex. The results indicated that AZP-2 significantly decreased the production of NO and ROS in the inflammatory model established by lipopolysaccharide (LPS) stimulated RAW264.7, particularly at the concentration of 200 μg/mL. Furthermore, AZP-2 significantly modulated the secretion of both pro-inflammatory and anti-inflammatory cytokines. Notably, the mechanism of AZP-2 exhibiting inhibitory effects was related to regulating the NF-κB signaling pathway. Overall, AZP-2 could be used as a potential anti-inflammatory agent for further in-depth studies.

Polysaccharide from Boletus aereus ameliorates DSS-induced colitis in mice by regulating the MANF/MUC2 signaling and gut microbiota

Inflammatory bowel diseases (IBD) are chronic inflammatory conditions characterized by disruptions in the colonic mucus barrier and gut microbiota. In this study, a novel soluble polysaccharide obtained from Boletus aereus (BAP) through water extraction was examined for its structure. The protective effects of BAP on colitis were investigated using a DSS-induced mice model. BAP was found to promote the expression of intestinal mucosal and tight junction proteins, restore the compromised mucus barrier, and suppress the activation of inflammatory signaling. Moreover, BAP reshape the gut microbiota and had a positive impact on the composition of the gut microbiota by reducing inflammation-related microbes. Additionally, BAP decreased cytokine levels through the MANF-BATF2 signaling pathway. Correlation analysis revealed that MANF was negatively correlated with the DAI and the level of cytokines. Furthermore, the depletion of gut microbiota using antibiotic partially inhabited the effect of BAP on the activation of MANF and Muc2, indicating the role of gut microbiota in its protective effect against colitis. In conclusion, BAP had an obvious activation on MANF under gut inflammation. This provides new insights into the prospective use of BAP as a functional food to enhance intestinal health.

Polysaccharide from Pleurotus tuber-regium mycelium improves DSS-induced colitis in mice by regulating inflammatory cytokines, oxidative stress and gut microbiota

Pleurotus tuber-regium (PTR) has been proved to have obvious pharmacological properties. In this study, a polysaccharide was extracted from the mycelium of PTR and administered to DSS-induced colitis mice to clarify the protective effect and mechanism of the PTR polysaccharide (PTRP) on colitis. The results showed that PTRP significantly improved the clinical symptoms and intestinal tissue damage caused by colitis and inhibited the secretion of pro-inflammatory cytokines and myeloperoxidase activity, while the levels of oxidative stress factors in mice decreased and the antioxidant capacity increased. The 16S rRNA sequencing of the mouse cecum content showed that PTRP changed the composition of gut microbiota, and the diversity and abundance of beneficial bacteria increased. In addition, PTRP also enhanced the production of short-chain fatty acids by regulating gut microbiota. In conclusion, our study shows that PTRP has the potential to relieve IBD symptoms and protect intestinal function by regulating inflammatory cytokines, oxidative stress and gut microbiota.

Advances in the regulation of radiation-induced apoptosis by polysaccharides: A review

Polysaccharides are biomolecules composed of monosaccharides that are widely found in animals, plants and microorganisms and are of interest for their various health benefits. Cumulative studies have shown that the modulation of radiation-induced apoptosis by polysaccharides can be effective in preventing and treating a wide range of radiation injuries with safety and few side effects. Therefore, this paper summarizes the monosaccharide compositions, molecular weights, and structure-activity relationships of natural polysaccharides that regulate radiation-induced apoptosis, and also reviews the molecular mechanisms by which these polysaccharides modulate radiation-induced apoptosis, primarily focusing on promoting cancer cell apoptosis to enhance radiotherapy efficacy, reducing radiation damage to normal tissues, and inhibiting apoptosis in normal cells. Additionally, the role of gut microbiota in mediating the interaction between polysaccharides and radiation is discussed, providing innovative ideas for various radiation injuries, including hematopoiesis, immunity, and organ damage. This review will contribute to a better understanding of the value of natural polysaccharides in the field of radiation and provide guidance for the development of natural radioprotective agents and radiosensitizers.

Fabrication of zein-tamarind seed polysaccharide-curcumin nanocomplexes: their characterization and impact on alleviating colitis and gut microbiota dysbiosis in mice

In this work, a zein-tamarind seed polysaccharide (TSP) co-delivery system was fabricated using an anti-solvent precipitation method. The formation mechanism, characterization, and effect on alleviating colitis and gut microbiota dysbiosis in mice of zein-TSP-curcumin (Z/T-Cur) nanocomplexes were investigated. Hydrogen bonding and the hydrophobic effect played a key role in the formation of Z/T-Cur nanocomplexes, and the interactions were spontaneous and driven by enthalpy. The encapsulation efficiency, loading capacity, and bioavailability increased from 60.8% (Zein-Cur) to 91.7% (Z/T-Cur1:1), from 6.1% (Zein-Cur) to 18.3% (Z/T-Cur1:1), and from 4.7% (Zein-Cur) to 20.0% (Z/T-Cur1:1), respectively. The Z/T-Cur significantly alleviated colitis symptoms in DSS-treated mice. Additionally, the prepared nanocomplexes rebalanced the gut microbiota composition of colitis mice by increasing the abundance of Akkermansia. Odoribacter and Monoglobus were rich in the Z-T-Cur treatment group, and Turicibacter and Bifidobacterium were rich in the zein-TSP treatment group. This study demonstrated that the TSP could be helpful in the targeted drug delivery system.

Structural characteristics of steamed Polygonatum cyrtonema polysaccharide and its bioactivity on colitis via improving the intestinal barrier and modifying the gut microbiota

Steamed Polygonatum cyrtonema has been commonly used clinically for its gaining effect, whose main active ingredient is a polysaccharide. A water-soluble polysaccharide named PSP-W-1 was isolated from steamed Polygonatum cyrtonema. PSP-W-1 was characterized as a galactan having a backbone consisting predominately of 1,4-β-linked Galp branched at the C-6 position by T-β-linked Galp with a molecular weight of 14.4 kDa. PSP-W-1 could inhibit the overproduction of inflammatory factors and inflammatory mediators (iNOS, IL-6, COX-2) in dextran sodium sulfate-induced colitis mice. Oral administration of PSP-W-1 dramatically alleviated colonic pathological damage, repaired the intestinal barrier (occludin and ZO-1) and regulated the intestinal microbiota by increasing the abundance of norank_f_Muribaculaceae, Lactobacillus and norank_f_norank_o_Clostridia UCG-014, while decreasing the abundance of Bacteroides and Escherichia-Shigella to alleviate colitis symptoms. Overall, our findings suggest that PSP-W-1 might be a therapeutic option for both the prevention and treatment of colitis.

Research progress on the structure, derivatives, pharmacological activity, and drug carrier capacity of Chinese yam polysaccharides: A review

Chinese yam is a traditional Chinese medicine that has a long history of medicinal and edible usage in China and is widely utilised in food, medicine, animal husbandry, and other industries. Chinese yam polysaccharides (CYPs) are among the main active components of Chinese yam. In recent decades, CYPs have received considerable attention because of their remarkable biological activities, such as immunomodulatory, antitumour, hypoglycaemic, hypolipidaemic, antioxidative, anti-inflammatory, and bacteriostatic effects. The structure and chemical alterations of polysaccharides are the main factors affecting their biological activities. CYPs are potential drug carriers owing to their excellent biodegradability and biocompatibility. There is a considerable amount of research on CYPs; however, a systematic summary is lacking. This review summarises the structural characteristics, derivative synthesis, biological activities, and their usage as drug carriers, providing a basis for future research, development, and application of CYPs.

The great potential of polysaccharides from natural resources in the treatment of asthma: A review

Despite significant progress in diagnosis and treatment, asthma remains a serious public health challenge. The conventional therapeutic drugs for asthma often have side effects and unsatisfactory clinical efficacy. Therefore, it is very urgent to develop new drugs to overcome the shortcomings of conventional drugs. Natural polysaccharides provide enormous resources for the development of drugs or health products, and they are receiving a lot of attention from scientists around the world due to their safety, effective anti-inflammatory and immune regulatory properties. Increasing evidence shows that polysaccharides have favorable biological activities in the respiratory disease, including asthma. This review provides an overview of primary literature on the recent advances of polysaccharides from natural resources in the treatment of asthma. The mechanisms and practicability of polysaccharides, including polysaccharides from plants, fungus, bacteria, alga, animals and others are reviewed. Finally, the further research of polysaccharides in the treatment of asthma are discussed. This review can provide a basis for further study of polysaccharides in the treatment of asthma and provides guidance for the development and clinical application of novel asthma treatment drugs.

Bioactive polysaccharides in different plant parts of Aconitum carmichaelii

BACKGROUND

Aconitum carmichaelii is an industrially cultivated medicinal plant in China and its lateral and mother roots are used in traditional Chinese medicine due to the presence of alkaloids. However, the rootlets and aerial parts are discarded after collection of the roots, and the non-toxic polysaccharides in this plant have attracted less attention than the alkaloids and poisonous features. In this study, five neutral and 14 acidic polysaccharide fractions were isolated systematically from different plant parts of A. carmichaelii, and their structural features and bioactivity were studied and compared.

RESULTS

The neutral fraction isolated from the rootlets differed from those isolated from the lateral and mother roots. It consisted of less starch and more possible mannans, galactans, and/or xyloglucans, being similar to those of the aerial parts. Pectic polysaccharides containing homogalacturonan and branched type-I rhamnogalacturonan (RG-I) were present in all plant parts of A. carmichaelii. However, more arabinogalactan (AG)-II side chains in the RG-I backbone were present in the aerial parts of the plants, while more amounts of arabinans were found in the roots. Various immunomodulatory effects were observed, determined by complement fixation activity and anti-inflammatory effects on the intestinal epithelial cells of all polysaccharide fractions.

CONCLUSION

This study highlighted the diversity of polysaccharides present in A. carmichaelii, especially in the unutilized plant parts, and showed their potential medicinal value. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Research progress on ginger polysaccharides: extraction, purification and structure-bioactivity relationship

Ginger is a widespread source of herbal medicine and traditional spices. Among its various bioactive components, ginger polysaccharides (GPs) have attracted the attention of researchers worldwide because of their significant bioactivity. Recent studies have demonstrated the antioxidant, antitumour, anti-inflammatory, immunomodulatory, hypoglycaemic, cough suppressant and thrombotic anticoagulant effects of GPs. However, the structure-bioactivity relationship of GPs has yet to be comprehensively investigated. This review aims to explore all the current published studies on GPs. It further examines various aspects, including the extraction and purification methods, structure, bioactivity, application and structure-bioactivity relationship of GPs. Thus, this review intends to provide a reference for future GP-related research and development.

Effect of Extracelluar Vesicles Derived from Akkermansia muciniphila on Intestinal Barrier in Colitis Mice

Inflammatory bowel disease (IBD) is a chronic and recurrent disease. It has been observed that the incidence and prevalence of IBD are increasing, which consequently raises the risk of developing colon cancer. Recently, the regulation of the intestinal barrier by probiotics has become an effective treatment for colitis. Akkermansia muciniphila-derived extracellular vesicles (Akk EVs) are nano-vesicles that contain multiple bioactive macromolecules with the potential to modulate the intestinal barrier. In this study, we used ultrafiltration in conjunction with high-speed centrifugation to extract Akk EVs. A lipopolysaccharide (LPS)-induced RAW264.7 cell model was established to assess the anti-inflammatory effects of Akk EVs. It was found that Akk EVs were able to be absorbed by RAW264.7 cells and significantly reduce the expression of nitric oxide (NO), TNF-α, and IL-1β (p < 0.05). We explored the preventative effects on colitis and the regulating effects on the intestinal barrier using a mouse colitis model caused by dextran sulfate sodium (DSS). The findings demonstrated that Akk EVs effectively prevented colitis symptoms and reduced colonic tissue injury. Additionally, Akk EVs significantly enhanced the effectiveness of the intestinal barrier by elevating the expression of MUC2 (0.53 ± 0.07), improving mucus integrity, and reducing intestinal permeability (p < 0.05). Moreover, Akk EVs increased the proportion of the beneficial bacteria Firmicutes (33.01 ± 0.09%) and downregulated the proportion of the harmful bacteria Proteobacteria (0.32 ± 0.27%). These findings suggest that Akk EVs possess the ability to regulate immune responses, protect intestinal barriers, and modulate the gut microbiota. The research presents a potential intervention approach for Akk EVs to prevent colitis.

Regulation on Pathway Metabolic Fluxes to Enhance Colanic Acid Production in Escherichia coli

Colanic acid (CA) is a natural polysaccharide macromolecule with rich and unique biological properties and is a promising candidate for use in food and cosmetics. To date, the efficient biosynthesis of CA and the influence of product accumulation on the strains used have yet to be precisely investigated. Herein, bottlenecks in the CA metabolic pathway were untangled by finely regulating the expression of manA, cpsG, fcl, and rcsA. Engineered strains produced CA at >1 g/L in shake flasks without dependence on cold temperatures, and it was verified in a 1 L bioreactor with a titer up to 18.64 g/L within 24 h. The accumulation of CA caused a decrease in the saturated fatty acid content (represented by C16:0 and C18:0) in the cell membrane. This study demonstrated pathway engineering for efficient CA production in cell factories and provided insights into the barriers and solutions faced in the biosynthesis of natural products.

Pectin from sunflower by-products obtained by ultrasound: Chemical characterization and in vivo evaluation of properties in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a public health challenge and the use of pectin for symptom amelioration is a promising option. In this work, sunflower pectin has been extracted without (CHP) and with assistance of ultrasound (USP) using sodium citrate as a food-grade extracting agent. At optimal conditions (64 °C, 23 min) the highest yield was obtained with ultrasound application (15.5 vs. 8.1 %). Both pectins were structurally characterized by 1H NMR, HPSEC-ELSD, FT-IR and GC-FID. Unlike CHP, USP showed a lower molecular weight, higher galacturonic acid, lower degree of methyl-esterification and, overall, higher viscosity. These characteristics could affect the anti-inflammatory activity of pectins, evaluated using DSS-induced IBD model mice. So, USP promoted the defence (ICAM-1) and repair of the gastrointestinal mucosa (TFF3, ZO-1) more effectively than CHP. These results demonstrate the potential amelioration of acute colitis in IBD mice through USP supplementation. Taking into account the biomarkers analysed, these results demonstrate, for the first time, the positive impact of sunflower pectin extracted by ultrasound under very soft conditions on inflammatory bowel disease that might open up new possibilities in the treatment of this serious pathology.

Dendrobium officinale Polysaccharide Alleviates Type 2 Diabetes Mellitus by Restoring Gut Microbiota and Repairing Intestinal Barrier via the LPS/TLR4/TRIF/NF-kB Axis

Dendrobium officinale polysaccharide (DOP), the main active component, has a variety of bioactivities. In this study, a type 2 diabetes mellitus (T2DM) and antibiotic-induced pseudo-germ-free mouse models were used to investigate the hypoglycemic mechanisms of DOP. The findings showed that DOP ameliorated dysfunctional glucolipid metabolism, lipopolysaccharide (LPS) leakage, and metabolic inflammation levels in T2DM mice. Furthermore, DOP significantly upregulated the mRNA expression of tight junction proteins Claudin-1, Occludin, and ZO-1 and reduced intestinal inflammation and oxidative stress damage through the LPS/TLR4/TRIF/NF-κB axis to repair the intestinal barrier. Interestingly, pseudo-germ-free mouse experiments confirmed that the above beneficial effects of DOP were dependent on gut microbiota. 16S rRNA analysis showed that DOP strongly inhibited the harmful bacterium Helicobacter by 94.57% and facilitated the proliferation of probiotics Allobaculum, Bifidobacterium, and Lactobacillus by 34.96, 139.41, and 88.95%, respectively. Therefore, DOP is capable of rebuilding certain specific intestinal microbiota to restore intestinal barrier injury, which supports the utilization of DOP as a new type of prebiotic in functional foods for T2DM.

Advances in Polysaccharide Production Based on the Co-Culture of Microbes

Microbial polysaccharides are natural carbohydrates that can confer adhesion capacity to cells and protect them from harsh environments. Due to their various physiological activities, these macromolecules are widely used in food, medicine, environmental, cosmetic, and textile applications. Microbial co-culture is an important strategy that is used to increase the production of microbial polysaccharides or produce new polysaccharides (structural alterations). This is achieved by exploiting the symbiotic/antagonistic/chemo-sensitive interactions between microbes and stimulating the expression of relevant silent genes. In this article, we review the performance of polysaccharides produced using microbial co-culture in terms of yield, antioxidant activity, and antibacterial, antitumor, and anti-inflammatory properties, in addition to the advantages and application prospects of co-culture. Moreover, the potential for microbial polysaccharides to be used in various applications is discussed.

Introduction to the Special Issue: Preparation, Physicochemical Properties and Application of Natural Plant Polysaccharides

As natural products, plant polysaccharides have been demonstrated to induce a variety of biological activities by numerous epidemiological investigations and interventional studies, including immunomodulation and antioxidant, antibacterial, antitumor, hypolipidemic, hypoglycemic processes, etc [...].

Polysaccharide-Based Stimulus-Responsive Nanomedicines for Combination Cancer Immunotherapy

Cancer immunotherapy is a promising antitumor approach, whereas nontherapeutic side effects, tumor microenvironment (TME) intricacy, and low tumor immunogenicity limit its therapeutic efficacy. In recent years, combination immunotherapy with other therapies has been proven to considerably increase antitumor efficacy. However, achieving codelivery of the drugs to the tumor site remains a major challenge. Stimulus-responsive nanodelivery systems show controlled drug delivery and precise drug release. Polysaccharides, a family of potential biomaterials, are widely used in the development of stimulus-responsive nanomedicines due to their unique physicochemical properties, biocompatibility, and modifiability. Here, the antitumor activity of polysaccharides and several combined immunotherapy strategies (e.g., immunotherapy combined with chemotherapy, photodynamic therapy, or photothermal therapy) are summarized. More importantly, the recent progress of polysaccharide-based stimulus-responsive nanomedicines for combination cancer immunotherapy is discussed, with the focus on construction of nanomedicine, targeted delivery, drug release, and enhanced antitumor effects. Finally, the limitations and application prospects of this new field are discussed.

Treatment Effects of Natural Products on Inflammatory Bowel Disease In Vivo and Their Mechanisms: Based on Animal Experiments

Inflammatory bowel disease (IBD) is a chronic, non-specific inflammatory disease of the intestine that can be classified as ulcerative colitis (UC) and Crohn's disease (CD). Currently, the incidence of IBD is still increasing in developing countries. However, current treatments for IBD have limitations and do not fully meet the needs of patients. There is a growing demand for new, safe, and highly effective alternative drugs for IBD patients. Natural products (NPs) are used in drug development and disease treatment because of their broad biological activity, low toxicity, and low side effects. Numerous studies have shown that some NPs have strong therapeutic effects on IBD. In this paper, we first reviewed the pathogenesis of IBD as well as current therapeutic approaches and drugs. Further, we summarized the therapeutic effects of 170 different sources of NPs on IBD and generalized their modes of action and therapeutic effects. Finally, we analyzed the potential mechanisms of NPs for the treatment of IBD. The aim of our review is to provide a systematic and credible summary, thus supporting the research on NPs for the treatment of IBD and providing a theoretical basis for the development and application of NPs in drugs and functional foods.

In Vitro Fecal Fermentation of Euphorbia humifusa-Derived Polysaccharides and Their Protective Effect against Ulcerative Colitis in Mice

Euphorbia humifusa is a plant species with medicinal and food characteristics used to treat diarrhea and other intestinal diseases. This study investigated the prebiotic effects of E. humifusa-derived polysaccharides (EHPs) on human colonic microbiota and their regulatory effects on ulcerative colitis (UC). Structural characterization showed that EHPs mainly consisted of galactose, glucose, and glucuronic acid and were heteropolysaccharides having molecular weights of 7.70 × 10³ and 1.76 × 10² kDa, respectively. EHPs were identified as poorly absorbed macromolecules, verified by the apparent permeability coefficient values (Papp < 1.0 × 10^-6 cm/s) and cellular uptake by Caco-2 cell monolayers. During in vitro fermentation studies, the contents of acetic, propionic, and valeric acids increased significantly in EHP-supplemented samples after 24 h compared to that in the control sample. Moreover, EHPs could alter the intestinal microbiota composition by increasing the relative abundance of Bifidobacterium and Holdemanella and reducing that of Escherichia-Shigella, Tyzzerella, and Parasutterella at the genus level. In a dextran sulfate sodium (DSS)-induced UC mouse model, EHPs alleviated UC symptoms by increasing the colon length, reversing the colon tissue damage and inhibiting pro-inflammatory cytokines. Overall, these results suggest that EHPs could be utilized as a potential prebiotic or a promising nutritional strategy for UC management.

Low Weight Polysaccharide of Hericium erinaceus Ameliorates Colitis via Inhibiting the NLRP3 Inflammasome Activation in Association with Gut Microbiota Modulation

Ulcerative colitis (UC), one of the typical inflammatory bowel diseases caused by dysregulated immunity, still requires novel therapeutic medicine with high efficacy and low toxicity. Hericium erinaceus has been widely used to treat different health problems especially gastrointestinal sickness in China for thousands of years. Here, we isolated, purified, and characterized a novel low weight polysaccharide (HEP10, Mw: 9.9 kDa) from the mycelia of H. erinaceus in submerged culture. We explored the therapeutic effect of HEP10 on UC and explored its underlying mechanisms. On one hand, HEP10 suppressed the production of TNF-α, IL-1β, IL-6, inducible iNOS, and COX-2 in LPS challenged murine macrophage RAW264.7 cells, as well as in colons from DSS-induced colitis mice. On the other hand, HEP10 treatment markedly suppressed the activation of NLRP3 inflammasome, NF-κB, AKT, and MAPK pathways. Moreover, HEP10 reversed DSS-induced alternation of the gut community composition and structure by significantly increasing Akkermansia muciniphila and also promoting functional shifts in gut microbiota. Structural equation modeling also highlighted that HEP10 can change widely through gut microbiota. In conclusion, HEP10 has a better prebiotic effect than the crude polysaccharides of H. erinaceus, which can be used as a novel dietary supplement and prebiotic to ameliorate colitis.

Enhancement of Cell Behavior by the Polysaccharide Extract of Arthrospira and Potential Biomedical Applications

Arthrospira is one of the most studied cyanobacteria and has been reported with practical applications. Among the substances derived from Arthrospira, polysaccharides have received relatively less attention than phycocyanins, though they have more abundant structural variations and specific properties. Herein, a new Arthrospira-derived sulfated polysaccharide was explored for its potential bioactive functions. The ability of this sulfated polysaccharide to promote the behavior of neural stem cells (NSCs) in three-dimensional hydrogel was examined for the first time. NSCs encapsulated in the sulfated polysaccharide-containing hydrogel showed better proliferation than the control hydrogel as well as a unique cell clustering behavior, i.e., formation of multicellular spherical clusters (40-60 μm). The sulfated polysaccharide, in an appropriate range of concentration (5 mg/mL), also maintained the stemness of NSCs in hydrogel and facilitated their differentiation. In addition, the potentials of the new sulfated polysaccharide as a coating material and as a component for drug carrier were verified. The sulfated polysaccharide-modified substrate exhibited superhydrophilicity (contact angle ~9°) and promoted cell adhesion to the substrate. Composite nanoparticles composed of the sulfated polysaccharide and other differently charged polysaccharides were produced with an average diameter of ~240 nm and estimated drug loading of ~18%. The new Arthrospira-derived sulfated polysaccharide is a promising candidate for cell culture, surface-modification, and drug-delivery applications in the biomedical field.