Dendrobium huoshanense polysaccharide regionally regulates intestinal mucosal barrier function and intestinal microbiota in mice

Dendrobium officinale leaf polysaccharides regulation of immune response and gut microbiota composition in cyclophosphamide-treated mice

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Polysaccharides extracted from Dendrobium officinale leaves could make better use of production waste.

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DOLP reduces gut barrier damage and cure inflammation.

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DOLP alleviated liver damage caused by drugs.

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DOLP regulated gut micorbiota and metabolism and increases the abundance of probiotics.

In this study, the polysaccharides extracted from Dendrobium officinale leaf (DOLP) was used in immune deficiency mice to evaluate the bioactivity. Thymus and spleen indices were calculated while the alleviation of the colon and liver histopathological progression was evaluated by H&E staining. The data indicated that DOLP improved immunity status by restoring the gut barrier and atrophy of immune organs. Cytokines levels as marker of inflammation were determined using ELISA in serum and colon. Which proved that DOLP inhibited the expression of pro-inflammatory cytokines (TNF-α, TGF- β1, IL-6, IL-1β) and promoted the expression of anti-inflammatory cytokines (IL-10). Short chain fatty acids (SCFAs) levels and microbial composition in feces were determined using GS and high-throughput sequencing. DOLP improved gut microbiota by increasing the relative abundance of total bacteria and probiotics such as Bacteroides, Lactobacillus and Lachnospiraceae. Therefore, DOLP has potential effect for the treatment of chronic immune diseases.

A Systematic Review on Polysaccharides from Dendrobium Genus: Recent Advances in the Preparation, Structural Characterization, Bioactive Molecular Mechanisms, and Applications

Dendrobium polysaccharides (DPSs) have aroused people's increasing attention in recent years as a result of their outstanding edible and medicinal values and non-toxic property. This review systematically summarized recent progress in the different preparation techniques, structural characteristics, modification, various pharmacological activities and molecular mechanisms, structure-activity relationships, and current industrial applications in the medicinal, food, and cosmetics fields of DPSs. Additionally, some recommendations for future investigations were provided. A variety of methods were applied for the extraction and purification of DPSs. They possessed primary structures (e.g., glucomannan, rhamnogalacturonan I type pectin, heteroxylan, and galactoglucan) and conformational structures (e.g., random coil, rod, globular, and a slight triple-helical). And different molecular weights, monosaccharide compositions, linkage types, and modifications could largely affect DPSs' bioactivities (e.g., immunomodulatory, anti-diabetic, hepatoprotective, gastrointestinal protective, antitumor, anti-inflammatory, and anti-oxidant activities). It was worth mentioning that DPSs were significant pharmaceutical remedies and therapeutic supplements especially due to their strong immunity enhancement abilities. We hope that this review will lay a solid foundation for further development and applications of Dendrobium polysaccharides.

The Protective Effects of Ginseng Polysaccharides and Their Effective Subfraction against Dextran Sodium Sulfate-Induced Colitis

Polysaccharides from Panax ginseng are natural carbohydrates with multiple activities. However, little was known about its functions on colitis. In this study, we aim to investigate the protective effects of ginseng polysaccharides and its effective subfraction on dextran sodium sulfate (DSS)-induced colitis. Water soluble ginseng polysaccharides (WGP) were obtained from dry ginseng root, then purified to neutral fraction (WGPN) and acidic fraction (WGPA) by ion exchange chromatography. An animal model was constructed with male Wistar rats, which were treated with a normal diet (con group), DSS (DSS group), WGP (WGP group), WGPN (WGPN group), and WGPA (WGPA group), respectively. Both WGP and WGPA alleviated the colitis symptoms and colon structure changes of colitis rats. They decreased the disease activity index (DAI) scores and improved colon health; reduced colon damage and recovered the intestinal barrier via regulating the tight-junction-related proteins (ZO-1 and Occludin); downregulated inflammatory cytokines (IL-1β, IL-2, IL-6, and IL-17) and inhibited the TLR4/MyD88/NF-κB-signaling pathway in the colon; regulated the diversity and composition of gut microbiota, especially the relative abundance of Ruminococcus; enhanced the production of SCFAs. In conclusion, WGP exerted a protective effect against colitis with its acidic fraction (WGPA) as an effective fraction. The results support the utilization and investigation of ginseng polysaccharides as a potential intervention strategy for the prevention of colitis.

Effects of laminarin zwitterionic carboxylate and sulfonate on the intestinal barrier function and gut microbiota

Ulcerative colitis (UC) has become a global chronic disease that keeps increasing. This study was to explore the treatment effectiveness of two functional zwitterionic laminarins, zwitterionic sulfonate (LZS) and zwitterionic carboxylate (LZC), in dextran sulfate sodium (DSS) induced mouse model. FT-IR and NMR techniques were used to characterize the aforementioned functional zwitterion. Compared to UC mice, the composition and diversity of gut microbiota were significantly increased in the treated mice. Specifically, the composition of Bacteroidetes increased and the level of Firmicutes decreased. Moreover, we demonstrated the alleviation of colitis by LZS and LZC reflected by the improved integrity of intestinal mucosa, which includes increased number of goblet cells, mucin protein production, maintenance of collagens, as well as the lower extent of intestinal fibrosis. These findings indicated the potentials of LZC and LZS as promising agents to prevent colitis via adjusting gut microbiota and maintaining intestinal barrier integrity.

Bifidobacterium lactis BL-99 protects mice with osteoporosis caused by colitis via gut inflammation and gut microbiota regulation

Patients diagnosed with inflammatory bowel disease or related conditions also frequently suffer from osteoporosis as a consequence of changes in the intestinal microenvironment and consequent dysbiosis. We hypothesized that anti-inflammatory probiotic treatment would be sufficient to alleviate intestinal inflammation and thereby prevent the development of osteoporosis. To that end, the ability of Bifidobacterium lactis BL-99 administration to protect against bone loss in an experimental model of dextran sodium sulfate-induced ulcerative colitis (UC) was analyzed, and the underlying molecular mechanisms were interrogated in detail. The results of these analyses revealed that BL-99 administration suppressed colitis-associated weight loss (P < 0.05), disease activity index scores, and the production of proinflammatory cytokines (TNF-α, IL-1β, IL-6, and IL-17) (P < 0.05). Colon tissue pathological sections similarly revealed BL-99-mediated reductions in tissue injury severity. Micro-computed tomography (Micro-CT) analyses further exhibited significant improvements in percent bone volume (BV/TV) as well as trabecular number and thickness in BL-99-treated animals (P < 0.05). Such probiotic supplementation also resulted in pronounced changes in the composition of the gut microbiota. Moreover, BL-99 intervention markedly increased the expression of intestinal barrier-related proteins (Claudin-1, MUC2, ZO-1, and Occludin). Together, these results suggest that BL-99 can be utilized as a beneficial probiotic preparation to prevent the incidence of osteoporosis in UC patients owing to its ability to shape the intestinal microflora and to suppress inflammatory cytokine production.

Modulatory effects of polysaccharides from plants, marine algae and edible mushrooms on gut microbiota and related health benefits: A review

Naturally occurring carbohydrate polymers containing non-starch polysaccharides (NPs) are a class of biomacromolecules isolated from plants, marine algae, and edible mushrooms, and their biological activities has shown potential uses in the prevention and treatment of human diseases. Importantly, NPs serve as prebiotics to provide health benefits to the host through stimulating the proliferation of beneficial gut microbiota (GM) and enhancing the production of short-chain fatty acids (SCFAs). The composition and diversity of GM play a critical role in regulating host health and have been extensively studied in recent years. In this review, the extraction, isolation, purification, and structural characterization of NPs derived from plants, marine algae, and edible mushrooms are outlined. Importantly, the degradation and metabolism of these NPs in the intestinal tract, the effects of NPs on the microbial community and SCFAs generation, and the beneficial effects of NPs on host health by modulating GM are systematically highlighted. Overall, we hope that this review can provide some theoretical references and a new perspective for applications of NPs as prebiotics in functional food and drug development.

Protective Effects of Natural Polysaccharides on Intestinal Barrier Injury: A Review

Owing to their minimal side effects and effective protection from oxidative stress, inflammation, and malignant growth, natural polysaccharides (NPs) are a potential adjuvant therapy for several diseases caused by intestinal barrier injury (IBI). More studies are accumulating on the protective effects of NPs with respect to IBI, but the underlying mechanisms remain unclear. Thus, this review aims to represent current studies that investigate the protective effects of NPs on IBI by directly maintaining intestinal epithelial barrier integrity (inhibiting oxidative stress, regulating inflammatory cytokine expression, and increasing tight junction protein expression) and indirectly regulating intestinal immunity and microbiota. Furthermore, the mechanisms underlying IBI development are briefly introduced, and the structure-activity relationships of polysaccharides with intestinal barrier protection effects are discussed. Potential developments and challenges associated with NPs exhibiting protective effects against IBI have also been highlighted to guide the application of NPs in the treatment of intestinal diseases caused by IBI.

Comparison of water- and alkali-extracted polysaccharides from Fuzhuan brick tea and their immunomodulatory effects in vitro and in vivo

In the present study, the purpose is to compare the effect of water extraction and alkali-assisted extraction on the structural characteristics and immunomodulatory activity of polysaccharides from Fuzhuan brick tea (FBTPs). The results indicated that water-extracted FBTPs (W-FBTPs) and alkali-extracted FBTPs (A-FBTPs) had similar molecular weights but different monosaccharide compositions, of which A-FBTPs had a higher yield and uronic acid groups corresponding to galacturonic acid (GalA). Moreover, A-FBTPs had stronger ability to promote phagocytic capacity, acid phosphatase activity and nitric oxide (NO) secretion in macrophages in vitro. In the in vivo study, A-FBTPs exhibited a promising effect to adjust the immune imbalance by enhancing the body features, antioxidant activities, immune response and intestinal mucosal barrier in cytoxan (CTX)-induced immunosuppressive mice. Besides, A-FBTP supplementation effectively improved CTX-induced gut microbiota dysbiosis, including promoting the abundance of beneficial bacteria (e.g., Lactobacillus) and short chain fatty acid (SCFA)-producing bacteria (e.g., Lachnospiraceae, Prevotellaceae and Ruminococcaceae), along with reducing the growth of potentially pathogenic microbes (e.g., Desulfovibrionaceae and Helicobacter). These findings suggested that alkaline extraction might be a promising way to obtain high-quality acidic polysaccharides from Fuzhuan brick tea (FBT), and A-FBTPs could be developed as novel potential prebiotics and immunomodulators for further application in food formulations.

Dendrobium fimbriatum Hook polysaccharide ameliorates dextran-sodium-sulfate-induced colitis in mice via improving intestinal barrier function, modulating intestinal microbiota, and reducing oxidative stress and inflammatory responses

The ameliorative effect of Dendrobium fimbriatum polysaccharide (cDFPW1) on ulcerative colitis (UC) was investigated using a dextran-sodium-sulfate-induced (DSS-induced) mouse model in the present study. The results showed that cDFPW1 effectively improved colitis in mice by ameliorating weight loss, disease activity index (DAI) and colonic pathological damage, and by protecting the intestinal barrier function integrity. Moreover, cDFPW1 modulated the composition and metabolism of intestinal microbiota through enhancing Romboutsia, Lactobacillus and Odoribacter, and reducing Parasutterella, Burkholderia-Caballeronia-Paraburkholderia and Acinetobacter in colitis mice. Notably, cDFPW1 significantly restored the homeostasis of Th17/regulatory T (Treg) cells and the expression of specific cytokines. Western blotting of colon tissues showed that cDFPW1 markedly up-regulated the expression of Nrf2 and inhibited the phosphorylation of NF-κB signaling. These results indicated that cDFPW1 possesses the potential of improving UC and its effect on palliating colitis may be connected with the regulation of Nrf2/NF-κB signaling.

Plant polysaccharides utilized by gut microbiota: New players in ameliorating cognitive impairment

Considerable evidence indicates the important role of gut microbiota in human health. Through the interaction with the host and diet, it secretes a myriad of metabolites to modulate biological processes essential for health. Cognitive impairment is a common feature of psychiatric and neurological disorders, which may seriously damage the quality of patients' life. Studies have found that cognitive impairment has a close relationship with gut microbiota, and plant polysaccharides intervention to maintain intestinal micro-ecological balance has a great impact on ameliorating cognitive impairment. This review introduced the interaction between gut microbiota and plant polysaccharides, and focused on signaling pathogenesis of gut microbiota in cognitive impairment. The effect of plant polysaccharides intervention on regulation of gut microbiota was also discussed, so as to provide a promising strategy for ameliorating cognitive impairment.

Anti-inflammatory and gut microbiota modulatory effects of polysaccharides from Fuzhuan brick tea on colitis in mice induced by dextran sulfate sodium

In this study, the effects of crude Fuzhuan brick tea polysaccharides (CFBTPS) and their purified fraction (FBTPS-3) on colitis induced by dextran sulfate sodium (DSS) in mice were investigated. Both CFBTPS and FBTPS-3 exhibited intestinal anti-inflammatory activities, including restoring body weight, colon length and solid fecal weight, and decreasing the disease activity index score in mice. Moreover, the expression of lipocalin-2 in colitis could be significantly reduced. The inflammatory cytokines (IL-6, IL-1β, IFN-γ and TNF-α) and lipopolysaccharides in the serum and the expression of inflammation-related mRNA in the colon tissue were decreased. Both CFBTPS and FBTPS-3 could increase tight junction proteins (Occludin, Claudin-1 and ZO-1), promoting the intestinal barrier function. For gut microbiota, DSS treatment resulted in abnormal proliferation of Bifidobacteria, while FBTPS-3 could restore this disorder to a certain extent. In addition, FBPTS-3 promoted the growth of probiotics such as Bacteroides, Parasutterella and Collinsella. Both CFBTPS and FBTPS-3 could attenuate colitis; what's more, FBTPS-3 exhibited a better anti-inflammatory effect than CFBTPS.

Cereus sinensis Polysaccharide Alleviates Antibiotic-Associated Diarrhea Based on Modulating the Gut Microbiota in C57BL/6 Mice

The present study investigated whether the purified polysaccharide from Cereus sinensis (CSP-1) had beneficial effects on mice with antibiotic-associated diarrhea (AAD). The effects of CSP-1 on gut microbiota were evaluated by 16S rRNA high-throughput sequencing. Results showed that CSP-1 increased the diversity and richness of gut microbiota. CSP-1 enriched Phasecolarctobacterium, Bifidobacterium and reduced the abundance of Parabacteroides, Sutterella, Coprobacillus to near normal levels, modifying the gut microbial community. Microbial metabolites were further analyzed by gas chromatography-mass spectrometry (GC-MS). Results indicated CSP-1 promoted the production of various short-chain fatty acids (SCFAs) and significantly improved intestinal microflora dysfunction in AAD mice. In addition, enzyme linked immunosorbent assay and hematoxylin-eosin staining were used to assess the effects of CSP-1 on cytokine levels and intestinal tissue in AAD mice. Results demonstrated that CSP-1 inhibited the secretion of interleukin-2 (IL-2), interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) and improved the intestinal barrier. Correspondingly, the daily records also showed that CSP-1 promoted recovery of diarrhea status score, water intake and body weight in mice with AAD. In short, CSP-1 helped alleviate AAD by regulating the inflammatory cytokines, altering the composition and richness of intestinal flora, promoting the production of SCFAs, improving the intestinal barrier as well as reversing the dysregulated microbiota function.

Polyphenols from Fu Brick Tea Reduce Obesity via Modulation of Gut Microbiota and Gut Microbiota-Related Intestinal Oxidative Stress and Barrier Function

Fu brick tea (FBT) is a microbial-fermented tea, which is produced by the solid-state fermentation of tea leaves. Previous studies have proved that FBT aqueous extracts could attenuate obesity and gut microbiota dysbiosis. However, the bioactive components in FBT that contribute to these activities remain unclear. In this study, we aimed to investigate the effects of FBT polyphenols (FBTPs) on obesity, gut microbiota, and gut microbiota-related intestinal oxidative stress and barrier function and to further investigate whether the antiobesity effect of FBTPs was dependent on the alteration of gut microbiota. The results showed that FBTP supplementation effectively attenuated obesity in high-fat diet (HFD)-fed rats. FBTP supplementation improved the intestinal oxidative stress and intestinal barrier function, including intestinal inflammation and the integrity of the intestinal barrier. Furthermore, FBTP intervention significantly attenuated HFD-induced gut microbiota dysbiosis, characterized by increased phylogenetic diversity and decreased Firmicutes/Bacteroidetes ratio. Certain core microbes, including Akkermansia muciniphila, Alloprevotella, Bacteroides, and Faecalibaculum, were also found to be improved by FBTPs. Moreover, the antiobesity effect of FBTPs was gut microbiota-dependent, as demonstrated by a fecal microbiota transplantation experiment. Collectively, we concluded that FBTPs reduced obesity by modulating the gut microbiota and gut microbiota-related intestinal oxidative stress and barrier function. Therefore, FBTPs may be used as prebiotic agents to treat obesity and gut microbiota dysbiosis in obese individuals.

Anti-gastric cancer activity of cultivated Dendrobium huoshanense stem polysaccharide in tumor-bearing mice: Effects of molecular weight and O-acetyl group

The present study aimed at assuring whether homogeneous cultivated Dendrobium huoshanense stem polysaccharide (cDHPS) could inhibit gastric cancer in vivo, and whether its anti-gastric cancer activity could be affected by its molecular weight and O-acetyl group. Three different fractions (cDHPS-I, cDHPS-II and cDHPS-III) with decreased molecular weights and one fraction (cDHPS-IV) without O-acetyl group were prepared from cDHPS. Their structures were identified systematically. The backbone of cDHPS-I-III was the same as that of cDHPS, while their relative molecular weights displayed a decreasing order as follows: cDHPS > cDHPS-I > cDHPS-II > cDHPS-III. The backbone of cDHPS-IV was similar to those of cDHPS and cDHPS-I-III, but with the absence of O-acetyl groups. Animal experiments exhibited that cDHPS and cDHPS-I-IV could significantly inhibit tumor growth, induce tumor cell apoptosis, suppress tumor angiogenesis and enhance T cell immune response of murine forestomach carcinoma (MFC) tumor-bearing mice. Moreover, all the above effects of cDHPS and cDHPS-I-IV on MFC tumor-bearing mice exhibited a decreasing order as follows: cDHPS > cDHPS-I > cDHPS-II > cDHPS-III > cDHPS-IV. The results suggest that cDHPS could inhibit gastric cancer in vivo, and its anti-gastric cancer activity was closely linked with its molecular weight and O-acetyl group.

Polysaccharides From the Roots of Millettia Speciosa Champ Modulate Gut Health and Ameliorate Cyclophosphamide-Induced Intestinal Injury and Immunosuppression

Cyclophosphamide (CTX), a common anticancer drug, can cause a variety of side effects such as immunosuppression and intestinal mucosal injury. Polysaccharides are the major bioactive components of the roots of Millettia Speciosa Champ and have gained attention for their immunomodulatory activity. This study was designed to evaluate the immunomodulatory effect of Millettia Speciosa Champ polysaccharide (MSCP) on CTX-induced mice and the possible mechanism. The results showed that MSCP attenuated the CTX-induced decrease in body weight and immune organ indices in mice and promoted the secretion of immune-related cytokines (IL-2, IL-4, IL-10, TNF-α, and IgG). Meanwhile, MSCP restored intestinal morphology, increased the ratio of villus height/crypt depth (V/C), and improved the number of goblet cells and mucins expression. At the mRNA level, MSCP activated the TLRs/MyD88/NF-κB p65 pathway and enhanced the expression of genes related to intestinal mucosal integrity (Occludin1, Claudin1, and MUC-2). In addition, MSCP as a prebiotic improved microbial community diversity, regulated the relative abundance of dominant microbiota from the phylum level to the genus level, restored CTX-induced gut microbial dysbiosis, and promoted short-chain fatty acid production in mice. Based on the present findings, MSCP may modulate the immune response depending on enhancing intestinal health, suggesting that MSCP holds promise as a promising immunostimulant in functional foods and drugs.

Supplementation of Alhagi honey polysaccharides contributes to the improvement of the intestinal immunity regulating the structure of intestinal flora in mice

Alhagi honey polysaccharides (AH), a main active component of Alhagi honey, are known to possess excellent pharmacological activities and have been widely used as dietary supplements in traditional Chinese medicine for thousands of years. This study is aimed to investigate the heath effect of AH on murine intestinal mucosal immune function and composition of the gut microbiome. ICR mice received daily intragastric administration of AH (three dosages, 200 mg kg^-1, 400 mg kg^-1, and 800 mg kg^-1) or saline for 7 consecutive days. Results indicated an improvement in the intestinal barrier function through increases in secretory immunoglobulin A (sIgA) and β-defensins. Simultaneously, AH also significantly stimulated IL-2, IL-4, IL-6, IL-10, IL-17, IFN-γ, and TNF-α cytokine secretion as compared to the control samples. Moreover, hematoxylin and eosin staining showed that AH enhanced the number of intraepithelial lymphocytes (IELs) in the small intestine. An obvious increase in the ratio of IgA⁺ cells of AH-treatment samples in the lamina propria was also detected by immunohistochemical staining. In addition, the CD3⁺, CD4⁺ and CD8⁺ T-cell ratio in mesenteric lymph nodes and Peyer's patches in the AH-treatment was significantly higher than that in the control group. Furthermore, 16S rDNA gene sequencing was used to monitor the dynamic changes in the gut microbiota. The result revealed that AH significantly increased the indexes of Shannon and obviously decreased the indexes of Simpson, suggesting the enhancement of the diversity and richness of the intestinal microbiome. Moreover, AH modulated the gut microbiome via increasing the abundance of probiotics and decreasing the levels of pathogenic bacteria. In summary, these results indicated that AH could be used as a prebiotic to enhance murine intestinal mucosal immunity and to modulate the gut microbiome.

Polysaccharides confer benefits in immune regulation and multiple sclerosis by interacting with gut microbiota

Pharmacological and clinical studies have consistently demonstrated that polysaccharides exhibit great potential on immune regulation. Polysaccharides can interact directly or indirectly with the immune system, triggering cell-cell communication and molecular recognition, leading to immunostimulatory responses. Gut microbiota is adept at foraging polysaccharides as energy sources and confers benefits in the context of immunity and chronic autoimmune disease, such as multiple sclerosis. A compelling set of interconnectedness between the gut microbiota, natural polysaccharides, and immune regulation has emerged. In this review, we highlighted the available avenues supporting the existence of these interactions, with a focus on cytokines-mediated and SCFAs-mediated pathways. Additionally, the neuroimmune mechanisms for gut microbiota communication with the brain in multiple sclerosis are also discussed, which will lay the ground for ameliorate multiple sclerosis via polysaccharide intervention.

Arsenic exposure induces intestinal barrier damage and consequent activation of gut-liver axis leading to inflammation and pyroptosis of liver in ducks

Arsenic is an important hazardous metalloid commonly found in polluted soil, rivers and groundwater. However, few studies exist regarding the effect of arsenic trioxide (ATO) on the gut-liver axis and consequent hepatotoxicity in waterfowl. Here, we investigated the influence of ATO on duck intestines and livers, and explored the role of the gut-liver axis in ATO-induced hepatotoxicity and intestinal toxicity. Our results demonstrated that ATO-exposure induced intestinal damage, liver inflammatory cell infiltration and vesicle steatosis. Additionally, the intestinal microbiota community in ATO-exposed ducks displayed significantly decreased α-diversity and an altered bacterial composition. Moreover, ATO-exposure markedly reduced the expression of intestinal barrier-related proteins (Claudin-1, MUC2, ZO-1 and Occludin), resulting in increased intestinal permeability and elevated lipopolysaccharide levels. Simultaneously, ATO-exposure also upregulated pyroptosis-related index levels in the liver and jejunum, and increased pro-inflammatory cytokine production (IFN-γ, TNF-α, IL-18, and IL-1β). Our further mechanistic studies showed that ATO-induced liver and jejunum inflammation were provoked by the activation of the LPS/TLR4/NF-κB signaling pathway and NLRP3 inflammasome. In summary, these results manifested that ATO exposure can cause liver and jejunal inflammation and pyroptosis, and the indirect gut-liver axis pathway may play an essential role in the potential mechanism of ATO-induced hepatotoxicity.

Chemotherapy-Induced Intestinal Microbiota Dysbiosis Impairs Mucosal Homeostasis by Modulating Toll-like Receptor Signaling Pathways

Chemotherapy-induced intestinal mucositis, a painful debilitating condition affecting up to 40–100% of patients undergoing chemotherapy, can reduce the patients’ quality of life, add health care costs and even postpone cancer treatment. In recent years, the relationships between intestinal microbiota dysbiosis and mucositis have drawn much attention in mucositis research. Chemotherapy can shape intestinal microbiota, which, in turn, can aggravate the mucositis through toll-like receptor (TLR) signaling pathways, leading to an increased expression of inflammatory mediators and elevated epithelial cell apoptosis but decreased epithelial cell differentiation and mucosal regeneration. This review summarizes relevant studies related to the relationships of mucositis with chemotherapy regimens, microbiota, TLRs, inflammatory mediators, and intestinal homeostasis, aiming to explore how gut microbiota affects the pathogenesis of mucositis and provides potential new strategies for mucositis alleviation and treatment and development of new therapies.

Self-assembled aggregations in Coptidis Rhizoma decoction dynamically regulate intestinal tissue permeability through Peyer's patch-associated immunity

Objective

To investigate the dynamic regulation of self-assembled aggregations (SAA) in Coptidis Rhizoma decoction on the permeability of intestinal tissue and the mechanism underlying.

Methods

The effects of SAA on berberine (Ber) absorption were respectively analyzed in an in situ intestinal perfusion model and in an Ussing Chamber jejunum model with or without Peyer's patches (PPs). The expression levels of ZO-1, Occludin and Claudin-1 were detected by immunofluorescence to evaluate the tight junction (TJ) between intestinal epithelium cells. The expression levels of T-box-containing protein expressed in T cells, signal transducers and activators of tranion-6, retinoic acid receptor-related orphan receptor γt and forkhead box P3 in PPs were detected by the reverse transcription-polymerase chain reaction and the secretions of interferon-γ (IFN-γ), interleukin-4 (IL-4), interleukin-17 (IL-17) and transforming growth factor-β (TGF-β) in PPs were evaluated by immunohistochemistry, to reflect the differentiation of T lymphocyte in PPs to helper T (Th) cell 1, Th2, Th17 and regulatory T (Treg) cell. To confirm the correlation between SAA in Coptidis Rhizoma decoction, PPs-associated immunity and intestinal epithelium permeability, SAA were administrated on an Ussing Chamber jejunum model with immunosuppressed PPs and evaluated its influences on intestinal tissue permeability and TJ proteins expression.

Results

SAA in Coptidis Rhizoma decoction could dose-dependently promote Ber absorption in jejunum segment, with the participation of PPs. The dose-dependent and dynamical regulations of SAA on permeability of intestinal tissue and TJ proteins expression level between intestinal epithelium cells occurred along with the dynamically changed T lymphocyte differentiation and immune effectors secretion in PPs. The administration of SAA on immunosuppressed PPs exhibited dose-dependent PPs activation, inducing dynamic promotion on intestinal tissue permeability and inhibition on TJ proteins expression.

Conclusion

SAA can improve the Ber absorption in small intestine, through the PPs-associated immunity induced dynamic regulation on intestinal tissue permeability and TJ proteins expression. These findings might enlighten the research of traditional Chinese medicine decoction.

Polysaccharide from Artocarpus heterophyllus Lam. (jackfruit) pulp modulates gut microbiota composition and improves short-chain fatty acids production

This study aimed to investigate the effects of polysaccharide from Artocarpus heterophyllus Lam. pulp (JFP-Ps) on gut microbiota composition and short-chain fatty acids production in mice. The microbial communities of V3 and V4 region 16S rRNA gene was amplified by PCR, then sequenced on an Illumina MiSeq PE250 platform and analyzed by multivariate statistical methods. The concentrations of short-chain fatty acids (SCFAs) were measured using gas chromatography (GC) equipped with a flame ionization detector (FID). The results showed that JFP-Ps significantly affected the levels of intestinal bacteria, including Bacteroidetes, Firmicutes, Proteobacteria, Cyanobacteria, Actinobacteria, Tenericutes, Deferribacteres and TM7. The concentrations of acetic acid, propionic acid, n-butyric acid and total SCFAs in mouse feces were significantly increased by treatment with JFP-Ps for 2 weeks. These results indicate that JFP-Ps is beneficial to the gut health and can be developed as a functional ingredient in relation to gut health.

Dendrobium huoshanense Polysaccharides Prevent Inflammatory Response of Ulcerative Colitis Rat through Inhibiting the NF-κB Signaling Pathway

The polysaccharides of the Chinese herbal medicine Dendrobium huoshanense exhibit anti-inflammatory effects in multiple organs through regulating the immune responses. In the present study, we constructed ulcerative colitis (UC) model rats using dextran sulfate sodium to investigate the anti-inflammatory effects of D. huoshanense polysaccharides (DHP). After oral administration of DHP for two weeks, the indices of UC symptoms, including the ratio of colon weight to length, Disease Activity Index (DAI), and Colon Mucosal Damage Index (CMDI), all decreased significantly compared with the UC model group. The histological sections also revealed better cell orders in DHP treatments than in the UC model rats. Moreover, in treatment with high dose of DHP (200 mg/kg), the treatment efficacy arrived the similar levels to those in the treatment with 300 mg/kg sulfasalazine, which is a typical medicine to treat UC. These results indicated that DHP has a high efficacy to treat UC in model rats. Furthermore, serum levels of interleukin-1β, tumor necrosis factor-α, interleukin-17, and transforming growth factor-β were assessed using the enzyme linked immunosorbent assay (ELISA) method, and the levels of nuclear factor-κB in colon tissue sections were determined using the immunohistochemical method. The results showed that all these indices decreased significantly after administration of DHP in UC model rats, which might be the mechanisms underlying the DHP-suppressed UC inflammation. Overall, this study indicated that DHP might be directly used to treat UC and is a promising source to develop novel drugs against UC.

Fermented Deer Blood Ameliorates Intense Exercise-Induced Fatigue via Modulating Small Intestine Microbiota and Metabolites in Mice

Intense and excessive exercise-induced fatigue has become an important health issue and can damage intestinal health. Deer blood, as a food byproduct with nutritional value, has been found to restore physical strength. However, little is known about the antifatigue effect of fermented deer blood (FDB) on intense exercise mice. The purpose of the present study is to investigate the antifatigue effect of FDB, and whether this effect is correlated with the altered small intestinal microbiota and metabolites in exercise mice. In this study, 5-week-old male C57BL/6J mice are given treadmill exercise with or without FDB supplementation (30 and 150 mg/kg/d) for 3 weeks. FDB significantly reduces metabolic byproduct accumulation, liver and intestinal damage, and enhances glycogen storage and antioxidant capacity in intense exercise mice. Moreover, FDB restructures the small intestinal microbiota by increasing the abundance of probiotics and butyric acid producing bacteria and decreasing the abundance of pathogenic bacteria. FDB also regulates the levels of metabolites involved in TCA cycle and amino acid metabolism in urine and small intestine content. Correlation analysis shows that FDB-modulated microbiota is highly associated with its antifatigue effect. FDB may ameliorate fatigue and intestinal injury through targeting small intestinal microbiota.

Transcriptome analysis reveals the protective role of fructo-oligosaccharide in colonic mucosal barriers in exercise-induced stressed mice

Most athletes continually endure mental and physical stress from intense exercise. Fructo-oligosaccharide (FOS) can reduce physical exhaustion, but the concrete mechanism behind it still needs further research. In this study, the effect of FOS on colonic mucosal barriers was investigated using an exercise-induced stress mouse model. Except for control individuals, mice were subject to cycles of 2-day exercise (at 20 rpm) interleaved by 5-day rest. The mice experienced a total of 6 days of exercise during the feeding period. FOS improved common indicators of exhaustion, such as glycogen storage in muscle. 16S rRNA data supported that changes in the gut microbiome were also closely related to stress status. Notably, Anaerotruncus was increased in mice under stress, while FOS facilitated the growth of Dorea, which is negatively associated with exhaustion. The RNA-seq analysis revealed that FOS could maintain the integrity of colonic epithelial barriers. For example, FOS significantly restored the expression of tight junctions (Occludin and Zonula occludens-1) in the colon, which was impaired under a stress state. Besides, the NOD-like receptor family pyrin domain containing 6 (NLRP6) inflammasome might contribute to the protection of the colonic mucosa by promoting the secretion of IL-18, Mucin2 (Muc2) and intestine lectin 1 (Itln1) in FOS-treated individuals. In short, FOS administration attenuated the damage of colonic mucosal barriers in exercise-induced stressed mice.

Structural characteristics and immunostimulatory activities of a new polysaccharide from Dendrobium fimbriatum Hook

A new polysaccharide (cDFP-W1) with high immunostimulatory activities was isolated from the stems of Dendrobium fimbriatum Hook. The analysis of the physicochemical properties showed that cDFP-W1 consisted of mannose and glucose in a molar ratio of 1 : 3.84, and its relative molecular weight was 4.0 × 10⁴ Da. Structural analysis implied that the linear backbone of cDFP-W1 was composed of α-1,4-d-Glcp, β-1,4-d-Manp, 3-O-acetyl-α-1,4-d-Glcp and α-1,4,6-d-Glcp, and its branches were the terminal β-d-Manp that was attached to the C-6 position of α-1,4,6-d-Glcp. An in vivo immunostimulatory assay exhibited that cDFP-W1 at 200 mg kg^-1 could significantly increase the proportions of CD4⁺ T-cell subpopulations, B cells, natural killer cells and dendritic cells, decrease the proportion of CD8⁺ T-cell subpopulations, and upregulate the percentage of activated macrophages (p < 0.01) in the spleen of mice. An in vitro immunostimulatory assay revealed that cDFP-W1 could effectively promote the proliferation of spleen lymphocytes, enhance the proliferation and phagocytosis of macrophage RAW264.7 cells, and stimulate the mRNA expression and extracellular release of NO, TNF-α and IL-1β of RAW264.7 cells. The western blot experiment suggested that the immunostimulatory activities of cDFP-W1 were closely related to the activation of MAPKs, NF-κB and PI3K/Akt signaling pathways.

PAMK Relieves LPS-Induced Enteritis and Improves Intestinal Flora Disorder in Goslings

Polysaccharide of Atractylodes macrocephala Koidz (PAMK) is a biologically active component of Atractylodes macrocephala, which has the effect of maintaining the immune homeostasis of the body. Therefore, this study constructed a model of PAMK to relieve LPS-induced gosling enteritis and observed the morphological changes of the small intestine after HE staining. ELISA was used to detect serum CRP, IL-1β, IL-6, and TNF-α levels; immunohistochemistry was used to detect the positive rate of IgA in the small intestine; TLR4, occludin, ZO-1, cytokines, and immunoglobulin mRNA expression in the small intestine were detected by qPCR; and intestinal flora of gosling excrement was analyzed by 16S rDNA sequencing to analyze the protective effect of PAMK on goslings enteritis and the impact on intestinal flora. The results showed that PAMK relieves LPS-induced gosling enteritis by maintaining the small intestine morphology, cytokine, tight junctions, and immunoglobulin relatively stable and improving the disorder of intestinal flora.

Polysaccharides in natural products that repair the damage to intestinal mucosa caused by cyclophosphamide and their mechanisms: A review

Cyclophosphamide (CTX) is a commonly used antitumor drug in clinical practice, and intestinal mucosal injury is one of its main toxic side effects, which seriously affects the treatment tolerance and prognosis of patients. Therefore, the prevention of intestinal mucosal injury is a research hotspot. Studies have shown that polysaccharides can effectively prevent and improve CTX-induced intestinal mucosal injury and immune system disorders. Recent research has elucidated the structure, biological function, and physicochemical properties of polysaccharides that prevent intestinal mucosal injury, and the potential mechanisms whereby they have this effect. In this paper, we review the recent progress made in understanding the effects of polysaccharides on intestinal mucosal injury and their protective mechanism in order to provide a reference for further research on the prevention of intestinal mucosal injury and the mechanisms involved in nutritional intervention.

Wheat germ glycoprotein regionally modulates immunosuppressed mouse intestinal immunity function from early life to adulthood

Wheat germ glycoprotein (WGP) is widely used due to its nutritional benefits and biological activity. This study evaluated the effects of WGP on intestinal-immunosuppressed mice from early life to adulthood and detected the underlying mechanism. The results revealed that WGP demonstrated no clinical side effects on the body index, serum total IgA level, protein expression and the morphology of intestine in newborn mice. In the phase of life, compared with the cyclophosphamide-treated group (CG), WGP clearly promoted the secretion of sIgA and effectively regulated the cytokine gene (IL-2, IFN-γ, TNF-α, IL-4, IL-6, IL-5, IL-17, and TGF-β1) expression in the intestine. Furthermore, WGP promoted the expression of CD40L and CD40, phosphorylation of IKKα/β and transcription of NF-κB-p65. The data as reported in this present analysis suggest that WGP can improve the intestinal immunity of newborn mice to adulthood via the CD40L-CD40-IKKα/β-NF-κB p65 signaling pathway.

Alhagi honey polysaccharides attenuate intestinal injury and immune suppression in cyclophosphamide-induced mice

Cyclophosphamide (CY), extensively used as an anti-cancer agent, could cause diverse side effects, such as immunosuppression and intestinal barrier damage. Alhagi honey polysaccharides (AH), polysaccharides isolated from Alhagi honey, are widely known for their anti-tumor and immunomodulatory activities. Herein, AH are evaluated for their ability to protect mice from CY-induced toxicity. The results demonstrated that treatment with AH could prevent the reduction in spleen and thymus indices as well as body weight, and significantly increase the Peyer's patch count in CY-induced mice and the levels of IL-2, IL-6, and TNF-α in serum, suggesting the role of Alhagi honey polysaccharides in alleviating the immunosuppression induced by CY. Moreover, administration of AH significantly increased the SOD activity and the expression level of β-defensin while decreasing the MDA content and DAO activity in CY-treated mice, which suggested a protective effect of AH on the intestinal barrier. Simultaneously, a CY-induced decrease in the ratio of villi length/crypt depth and the number of intraepithelial lymphocytes and goblet cells was reversed by AH treatment, as were the alterations in the expression of ZO-1, mucin-2, E-cadherin and occludin in the intestine and the concentrations of SCFAs in the colon. Furthermore, AH have the ability to regulate the MAPK pathway in CY-mice models to reduce CY-induced toxicity, evidenced by the increased expression of p-ERK and inhibited production of both p-JNK and p-p38. Overall, these results showed that AH could be used as protective agents to mitigate intestinal injury and immune suppression in mice induced by CY.

Yacón (Smallanthus sonchifolius) prevented inflammation, oxidative stress, and intestinal alterations in an animal model of colorectal carcinogenesis

BACKGROUND

Yacón (Smallanthus sonchifolius) roots store carbohydrate in the form of prebiotic fructooligosaccharides (FOS), which improve intestinal health. Yacon has the potential to prevent the intestinal barrier alterations associated with colorectal cancer (CRC). This study aimed to investigate the preventive effects of yacón flour (YF) on alterations promoted by CRC induced by 1,2-dimethylhydrazine in rats.

RESULTS

CRC increased tumor necrosis factor alpha levels (group CY = 10.2 ± 0.72; group C = 9.6 ± 1.0; group Y = 5.8 ± 0.54; group S = 5.95 ± 0.6 pg mL^-1 ) and short-chain fatty acid production, and decreased total antioxidant capacity (group CY = 4.7 ± 0.72; group C = 3.3 ± 0.3; group Y = 4.1 ± 0.47; group S = 6.7 ± 0.78 U mL^-1 ). Furthermore, YF treatment reduced intraluminal pH (group CY = 6.45 ± 0.47; group C = 7.65 ± 0.44; group Y = 6.75 ± 0.46; group S = 8.13 ± 0.2), lactulose/mannitol ratio, tumor necrosis factor-alpha (TNF-α)/interleukin (IL)-10 ratio, and increased secretory immunoglobulin A (group CY = 9.48 ± 1.46; group C = 10.95 ± 3.87; group Y = 15.95 ± 7.36; group S = 9.19 ± 1.52), but did not affect IL-10, IL-12, and TNF-α levels nor the IL-12/IL-10 ratio.

CONCLUSION

YF as a source of fructooligosaccharides may help to maintain the integrity of intestinal health, which is altered in induced CRC in rats. © 2020 Society of Chemical Industry.

Modulation of gut homeostasis by exopolysaccharides from Aspergillus cristatus (MK346334), a strain of fungus isolated from Fuzhuan brick tea, contributes to immunomodulatory activity in cyclophosphamide-treated mice

In this study, the crude exopolysaccharides (CEPSs) from fungus Aspergillus cristatus (MK346334, NCBI) isolated from Fuzhuan brick tea and its main purified fraction (EPSs-2) were investigated. Using the RAW264.7 cell model, EPSs-2 exhibited an excellent immunomodulatory effect in vitro. Then, the regulating effects of EPSs on immune function and gut microbiota were evaluated using a cyclophosphamide (Cy)-induced mice model. It was found that both CEPSs and EPSs-2 improved the body weight loss, immune organ indexes as well as the levels of TNF-α, IL-1β, IFN-γ and IgA, exhibiting potent immunoregulatory activity. Moreover, CEPSs and EPSs-2 not only attenuated the intestinal tissue damage, but also promoted the production of short-chain fatty acids and modulated the microbial composition by increasing the growth of Muribaculaceae, Prevotellaceae_UCG-001, Bacteroides, Parabacteroides and Tidjanibacter, while decreasing the relative abundances of Helicobacter, Bilophila, Mucispirillum, Lachnospiraceae, Ruminococcaceae and Clostridiales. These results indicated that the EPSs, especially EPSs-2, exhibited immunomodulatory activity associated with the modulation of gut microbiota to maintain gut homeostasis, which provided evidence for the development of novel potential prebiotics and immunomodulators.

Self-recovery study of the adverse effects of fluoride on small intestine: Involvement of pyroptosis induced inflammation

Increasing investigations suggest that fluoride (F) exposure was associated with gastrointestinal diseases, but related literatures were still largely insufficient and the underlying mechanisms have not been fully elucidated. Moreover, previous study in our lab reported F toxicity has the reversible tendency, but it still needs to be further explored. To address this issue, we established a 90 days F exposure and 15 days & 30 days self-recovery mice model, including control and three F groups (25, 50 and 100 mg/L sodium fluoride (NaF)) in each period. The results revealed that after 90 days F exposure, histological structure and ultrastructure of small intestine were markedly disrupted; the value of villus height to crypt depth, and expressions of tight junctions related mRNA and proteins were significantly decreased; intestinal permeability, pro-inflammatory cytokines and pyroptosis related mRNA and proteins were notably increased in duodenum, jejunum and ileum. However, intriguingly, after 30 days recovery period, indices in F groups almost all have recovered towards normalcy. Collectively, this study demonstrated that F exposure could impair the structure and epithelial barrier function of small intestine, leading to the intestinal inflammation, and pyroptosis may contribute to this damage; Furthermore, F toxicity on small intestine is reversible, and could be restored when off the F exposure environment for a certain period of time. Additionally, among the three regions of small intestine, duodenum seems more vulnerable to F exposure than jejunum and ileum.

Anti-Inflammatory and Intestinal Microbiota Modulation Properties of Jinxiang Garlic (Allium sativum L.) Polysaccharides toward Dextran Sodium Sulfate-Induced Colitis

Garlic polysaccharides are great potential agents because of their anti-inflammation, antioxidation, and immunomodulation properties. However, few studies have reported their anti-inflammatory effects on improving the colon system and corresponding intestinal microbiota. Herein, a water-soluble garlic polysaccharide (WSGP) was extracted from Jinxiang garlic to evaluate its effects on ameliorating dextran sulfate sodium (DSS)-induced colitis in a mouse model. The results showed that (1) after administration of the WSGP (200 or 400 mg/kg/day), the feed intake, body weight, and colon length of colitic mice were increased, while the disease activity index and the histological score of colitic mice were decreased; (2) the WSGP reduced the colonic tissue damage and inhibited the expression of inflammatory factors (interleukin 6, interleukin 1 beta , and tumor necrosis factor alpha); and (3) the WSGP enhanced the production of short-chain fatty acids and improved the composition of intestinal microbiota. The key microorganisms, including Muribaculaceae, Lachnospiraceae, Lachnospiraceae_NK4A136_group, Mucispirillum, Helicobacter, Ruminococcus_1, and Ruminiclostridium_5, were identified to be associated with inflammatory bowel diseases. Taken together, this study proved that WSGP supplementation could alleviate DSS-induced colitis by improving mucosal barriers, blocking proinflammatory cytokines, and modulating gut microbiota.

Marine polysaccharides from Gelidium pacificum Okamura and Cereus sinensis reveal prebiotic functions

Many marine polysaccharides as prebiotics can promote host health by modulating gut microbiota. This study investigated the beneficial effects of purified marine plant-derived Gelidium pacificum Okamura polysaccharide (GPOP-1) and marine animal-derived Cereus sinensis polysaccharide (CSP-1) on normal mice by modulating gut microbiota. The composition and diversity of gut microbiota were evaluated using 16S rRNA high-throughput sequencing. The results showed that GPOP-1 and CSP-1 altered the composition of the gut microbiota and promoted the growth of beneficial bacteria. At the genus level, GPOP-1 increased the relative abundance of Bacteroides, Phascolarctobacterium, and decreased the relative abundance of Ruminococcus, Helicobacter, Allobaculum, Dorea and AF12. While CSP-1 increased the relative abundance of Coprococcus, Adlercreutzia, Roseburia, Phascolarctobacterium, and decreased the relative abundance of Bacteroides, Ruminococcus and Oscillospira. The changes in the gut microbiota may affect the body weight, immune organ index and the production of short-chain fatty acids in normal mice. Compared to the normal control group, GPOP-1 decreased average weight gain while CSP-1 increased average weight gain. Furthermore, both GPOP-1 and CSP-1 significantly increased thymus and spleen indexes and total short chain fatty acids production in mice. In summary, GPOP-1 and CSP-1 exerted prebiotic effects on normal mice.

Uncovering the Molecular Mechanism of the Qiang-Xin 1 Formula on Sepsis-Induced Cardiac Dysfunction Based on Systems Pharmacology

Cardiac dysfunction is a critical manifestation of sepsis-induced multiorgan failure and results in the high mortality of sepsis. Our previous study demonstrated that a traditional Chinese medicine formula, Qiang-Xin 1 (QX1), ameliorates cardiac tissue damage in septic mice; however, the underlying pharmacology mechanism remains to be elucidated. The present study was aimed at clarifying the protective mechanism of the QX1 formula on sepsis-induced cardiac dysfunction. The moderate sepsis model of mice was established by cecal ligation and puncture surgery. Treatment with the QX1 formula improved the 7-day survival outcome, attenuated cardiac dysfunction, and ameliorated the disruption of myocardial structure in septic mice. Subsequent systems pharmacology analysis found that 63 bioactive compounds and the related 79 candidate target proteins were screened from the QX1 formula. The network analysis showed that the QX1 active components quercetin, formononetin, kaempferol, taxifolin, cryptotanshinone, and tanshinone IIA had a good binding activity with screened targets. The integrating pathway analysis indicated the calcium, PI3K/AKT, MAPK, and Toll-like receptor signaling pathways may be involved in the protective effect of the QX1 formula on sepsis-induced cardiac dysfunction. Further, experimental validation showed that the QX1 formula inhibited the activity of calcium/calmodulin-dependent protein kinase II (CaMKII), MAPK (P38, ERK1/2, and JNK), and TLR4/NF-κB signaling pathways but promoted the activation of the PI3K/AKT pathway. A cytokine array found that the QX1 formula attenuated sepsis-induced upregulated levels of serum IFN-γ, IL-1β, IL-3, IL-6, IL-17, IL-4, IL-10, and TNF-α. Our data suggested that QX1 may represent a novel therapeutic strategy for sepsis by suppressing the activity of calcium, MAPK, and TLR4/NF-κB pathways, but promoting the activation of AKT, thus controlling cytokine storm and regulating immune balance. The present study demonstrated the multicomponent, multitarget, and multipathway characteristics of the QX1 formula and provided a novel understanding of the QX1 formula in the clinical application on cardiac dysfunction-related diseases.

The role of MUC2 mucin in intestinal homeostasis and the impact of dietary components on MUC2 expression

MUC2 mucin is an important secretory protein found in the human gut. Recent studies indicated that MUC2 mucin plays a role in the protection of gut barrier, the regulation of microbiome homeostasis and the prevention of diseases. In this review, the physiological properties of MUC2 mucin and its interactions with the intestinal microbiome are firstly discussed. Its roles in intestinal diseases including inflammatory bowel disease, colorectal cancer and parasitic infections are concluded. We also reviewed dietary components known to have modulative effects on MUC2 mucin expression, such as polysaccharides, amino acids and polyphenols.

Modulation of Apoptosis by Plant Polysaccharides for Exerting Anti-Cancer Effects: A Review

Cancer has become a significant public health problem with high disease burden and mortality. At present, radiotherapy and chemotherapy are the main means of treating cancer, but they have shown serious safety problems. The severity of this problem has caused further attention and research on effective and safe cancer treatment methods. Polysaccharides are natural products with anti-cancer activity that are widely present in a lot of plants, and many studies have found that inducing apoptosis of cancer cells is one of their important mechanisms. Therefore, this article reviews the various ways in which plant polysaccharides promote apoptosis of cancer cells. The major apoptotic pathways involved include the mitochondrial pathway, the death receptor pathway, and their upstream signal transduction such as MAPK pathway, PI3K/AKT pathway, and NF-κB pathway. Moreover, the paper has also been focused on the absorption and toxicity of plant polysaccharides with reference to extant literature, making the research more scientific and comprehensive. It is hoped that this review could provide some directions for the future development of plant polysaccharides as anticancer drugs in pharmacological experiments and clinical researches.

Beneficial effects of sulfated polysaccharides from the red seaweed Gelidium pacificum Okamura on mice with antibiotic-associated diarrhea

The purpose of this study was to investigate whether Gelidium pacificum Okamura polysaccharides (sulfated polysaccharide, GPOP-1) had beneficial effects on mice with antibiotic-associated diarrhea (AAD). Compared with the natural recovery group, GPOP-1 increased the richness and diversity of the gut microbiome, as well as altered the composition of the gut microbiota. At the genus level, GPOP-1 significantly increased the relative abundance of Bacteroides, Oscillospira, and Bifidobacterium and decreased the relative abundance of Parabacteroides, Sutterella, and AF12. The metabolic pathway differences according to the Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed that the metabolic function of the gut microbiota could be significantly improved by GPOP-1. Furthermore, GPOP-1 downregulated the concentrations of inflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-2 (IL-2), alleviated the pathological features of the cecum, and increased the contents of acetates, propionates, butyrates, and total short-chain fatty acids (SCFAs). Results indicated that GPOP-1 had beneficial effects on mice with AAD by promoting the recovery of the gut microbiota and mucosal barrier function, reversing metabolic disorders, downregulating the levels of inflammatory cytokines and improving the content of SCFAs.

Cross-Talk between Gut Microbiota and the Heart: A New Target for the Herbal Medicine Treatment of Heart Failure?

Heart failure (HF) is the severe and terminal stage of various heart diseases. A growing number of studies have suggested the potential clinical significance of gut microbiota in the pathophysiology of HF. Herbal medicine (HM) plays a role in rebalancing the composition of gut microbiota and is widely used in the prevention and treatment of HF. There are many similarities between intestinal microecology and the traditional Chinese medicine (TCM) theory, such as the holistic concept and the theory of the “heart's connection with the small intestine.” These similarities provide a theoretical basis for HM to prevent and treat diseases by regulating the intestinal flora and its metabolites. In this work, the cross-talk between gut microbiota and the heart is reviewed, and the relationship between TCM and gut microbiota is discussed. Based on the current literature and research, we hypothesize that the cross-talk between gut microbiota and the heart may offer a new therapeutic target for HF intervention.

Dendrobium officinale Polysaccharide Protected CCl4-Induced Liver Fibrosis Through Intestinal Homeostasis and the LPS-TLR4-NF-κB Signaling Pathway

We explored the therapeutic effects of Dendrobium officinale polysaccharide (DOP) on CCl₄-induced liver fibrosis with respect to the intestinal hepatic axis using a rat model. Histopathological staining results showed that DOP alleviated extensive fibrous tissue proliferation in interstitium and lessened intestinal mucosal damage. Western blot and PCR results showed that DOP maintained intestinal balance by upregulating the expression of tight junction proteins such as occludin, claudin-1, ZO-1, and Bcl-2 proteins while downregulating the expression of Bax and caspase-3 proteins in the intestine. The transepithelial electrical resistance (TEER) value of the LPS-induced Caco-2 monolayer cell model was increased after DOP administration. These illustrated that DOP can protect the intestinal mucosal barrier function. DOP also inhibited activation of the LPS-TLR4-NF-κB signaling pathway to reduce the contents of inflammatory factors TGF-β and TNF-α, increased the expression of anti-inflammatory factor IL-10, and significantly decreased α-SMA and collagen I expression. These results indicated that DOP maintained intestinal homeostasis by enhancing tight junctions between intestinal cells and reducing apoptosis, thereby inhibiting activation of the LPS-TLR4-NF-κB signaling pathway to protect against liver fibrosis.

Intestinal Barrier Dysfunction, LPS Translocation, and Disease Development

The intestinal barrier is complex and consists of multiple layers, and it provides a physical and functional barrier to the transport of luminal contents to systemic circulation. While the epithelial cell layer and the outer/inner mucin layer constitute the physical barrier and are often referred to as the intestinal barrier, intestinal alkaline phosphatase (IAP) produced by epithelial cells and antibacterial proteins secreted by Panneth cells represent the functional barrier. While antibacterial proteins play an important role in the host defense against gut microbes, IAP detoxifies bacterial endotoxin lipopolysaccharide (LPS) by catalyzing the dephosphorylation of the active/toxic Lipid A moiety, preventing local inflammation as well as the translocation of active LPS into systemic circulation. The causal relationship between circulating LPS levels and the development of multiple diseases underscores the importance of detailed examination of changes in the “layers” of the intestinal barrier associated with disease development and how this dysfunction can be attenuated by targeted interventions. To develop targeted therapies for improving intestinal barrier function, it is imperative to have a deeper understanding of the intestinal barrier itself, the mechanisms underlying the development of diseases due to barrier dysfunction (eg, high circulating LPS levels), the assessment of intestinal barrier function under diseased conditions, and of how individual layers of the intestinal barrier can be beneficially modulated to potentially attenuate the development of associated diseases. This review summarizes the current knowledge of the composition of the intestinal barrier and its assessment and modulation for the development of potential therapies for barrier dysfunction-associated diseases.

Cultured Cordyceps sinensis polysaccharides modulate intestinal mucosal immunity and gut microbiota in cyclophosphamide-treated mice

The present study aimed to investigate the protective effect of cultured Cordyceps sinensis polysaccharides (CSP) on cyclophosphamide (Cy)-induced intestinal mucosal immunosuppression and microbial dysbiosis in mice. Results showed that CSP stimulated cytokines secretion (IL-12, IFN-γ, IL-4, IL-13, IL-6, IL-17, IL-10, TGF-β3, TNF-α, IL-2, IL-21) and transcription factors production (T-bet, GATA-3, RORγt, Foxp3). TLRs (TLR-2, TLR-4, TLR-6) and NF-κB pathway key proteins (p-IκB-α, NF-κB p65) were also upregulated after CSP administration. Moreover, CSP recovered SCFAs levels which decreased by Cy treatment. Furthermore, 16S rRNA sequencing of fecal samples was performed. α-diversity and β-diversity analysis revealed CSP improved microbial community diversity and modulated the overall structure of gut microbiota. Taxonomic composition analysis found that CSP increased the abundance of probiotics (Lactobacillus, Bifidobacterium, Bacteroides) and decreased pathogenic bacteria (Clostridium, Flexispira). These findings suggested the potential of CSP as a prebiotics to reduce side effects of Cy on intestinal mucosal immunity and gut microbiota.

Dietary Supplementation with Galactooligosaccharides Attenuates High-Fat, High-Cholesterol Diet-Induced Glucose Intolerance and Disruption of Colonic Mucin Layer in C57BL/6 Mice and Reduces Atherosclerosis in Ldlr-/- Mice

BACKGROUND

A Western-type diet (WD), rich in fat and cholesterol but deficient in fiber, induces development of diabetes and atherosclerosis. Colonic bacteria use the gut's mucous lining as an alternate energy source during periods of fiber deficiency, resulting in intestinal barrier erosion.

OBJECTIVE

We hypothesized that supplementing a WD with galactooligosaccharide (GOS) fiber would attenuate WD-induced mucin layer disruption and attenuate development of metabolic diseases.

METHODS

C57BL/6 mice (both sexes, 8-10 wk of age) were fed a standard rodent diet (TD7012, reference) or a high-fat, high-cholesterol-containing WD (TD88137, 21% fat, 0.15% cholesterol, 19.5% caesin) or a WD supplemented with 5% GOS fiber (TD170432, WD + GOS) for 16 wk. WD-fed mice that were gavaged daily with curcumin (100 mg/kg) served as positive controls. Glucose tolerance, colonic mucin layer, gene expression, and circulating macrophage/neutrophil levels were determined. Hyperlipidemic Ldlr-/- mice (both sexes, 8-10 wk of age) fed a WD with or without GOS supplementation (for 16 wk) were used to assess plasma LPS and atherosclerosis. Effects of dietary supplementation on different parameters were compared for each genotype.

RESULTS

Compared with a WD, glucose tolerance was significantly improved in male C57BL/6 mice fed a WD + GOS (mean ± SEM: AUC = 53.6 ± 43.9 compared with 45.4 ± 33.3 g ⋅ min/dL; P = 0.015). Continuity of colonic mucin layer (MUC-2 expression) was improved in mice receiving GOS supplementation, indicating improved intestinal barrier. GOS supplementation also reduced circulating macrophages (30% decrease) and neutrophils (60% decrease), suggesting diminished systemic inflammation. In Ldlr-/- mice, GOS supplementation significantly reduced plasma LPS concentrations (mean ± SEM: 0.81 ±  0.43 EU/mL compared with 0.32 ± 0.26 EU/mL, P   < 0.0001, in females and 0.56 ± 0.24 EU/mL compared with 0.34 ± 0.12 EU/mL, P = 0.036, in males), improved glucose tolerance in male mice, and attenuated atherosclerotic lesion area (mean ± SEM: 54.2% ± 6.19% compared with 43.0% ± 35.12%, P   = 0.0006, in females and 54.6% ± 3.99% compared with 43.1% ± 8.11%, P = 0.003, in males).

CONCLUSIONS

GOS fiber supplementation improves intestinal barrier in C57BL/6 and Ldlr-/- mice and significantly attenuates WD-induced metabolic diseases and, therefore, may represent a novel strategy for management of these diseases.