Mucoadhesive role of tamarind xyloglucan on inflammation attenuates ulcerative colitis

Catalase catalyzed tannic acid-Fe3+ network coating: A theranostic strategy for intestinal barrier restoration

Epithelial barrier impairment of intestinal inflammation leads to the leakage of bacteria, antigens and consequent persistent immune imbalance. Restoring the barrier function holds promise for management of intestinal inflammation, while the theragnostic strategies are limited. In this study, we developed a novel coating by catalase (CAT)-catalyzed polymerization of tannic acid (TA) and combined chelation network with Fe3+. TA-Fe3+ coating was self-polymerized in situ along the small intestinal mucosa, demonstrating persistent adhesion properties and protective function. In enteritis models, sequential administration of TA-Fe3+ complex solution effectively restored the barrier function and alleviated the intestinal inflammation. Overexpressed CAT in inflammatory lesion is more favorable for the in situ targeting growth of TA-Fe3+ coating onto the defective barrier. Based on the high longitudinal relaxivity of Fe3+, the pathologically catalyzed coating facilitated the visualization of intestinal barrier impairment through MRI. In conclusion, the novel TA-Fe3+ delivery coating proposed an alternative approach to promote theranostic intervention for intestinal diseases.

Efficient degradation and enhanced α-glucosidase inhibitory activity of apricot polysaccharides through non-thermal plasma assisted non-metallic Fenton reaction

Dielectric barrier discharge (DBD) was a commonly used non-thermal plasma (CP) technology. This paper aimed to enhance the biological activity of apricot polysaccharides (AP) by using dielectric barrier discharge (DBD-CP) assisted H2O2-VC Fenton reaction for degradation. The degradation conditions were optimized through response surface methodology. The molecular weight (Mw) of degraded apricot polysaccharides (DAP) was 19.71 kDa, which was 7.25 % of AP. The inhibition rate of DAP (2 mg/mL) was 82.8 ± 3.27 %, which was 106.87 % higher than that of AP. DBD-CP/H2O2-VC degradation changed the monosaccharide composition of AP and improved the linearity of polysaccharide chains. In addition, a novel apricot polysaccharide DAP-2 with a Mw of only 6.60 kDa was isolated from DAP. The repeating units of the main chain of DAP-2 were →4)-α-D-GalpA-(1 →, the branch chain was mainly composed of α-D-GalpA-(1 → 2)-α-L-Rhap-(1→ connected to O-3 position →3,4)-α-D-GalpA-(1→. The complex structure formed by the combination of DAP-2 and α-glucosidase was stable. DAP-2 had a higher α-glucosidase binding ability than the acarbose. These results suggested that DAP-2 had the potential to be developed as a potential hypoglycemic functional food and drug.

Efficacy and Safety of Pea Protein and Xyloglucan Versus Simethicone in Functional Abdominal Bloating and Distension

BACKGROUND

Functional Abdominal Bloating and Distension (FABD) is a multifaceted condition related in part to trapped gas, with changes in the intestinal barrier and small intestinal bacterial overgrowth (SIBO), which lead to gas production. Currently, there are no treatments targeting the etiology of FABD.

METHODS

This double-blind, multicenter, randomized study evaluated the safety and efficacy of a product containing xyloglucan and pea proteins (XG + PP) compared with simethicone, both administered orally (three times daily) for 20 consecutive days. Eighty-eight patients with FABD were randomly assigned to the two groups in a 1:1 ratio. Primary outcome was safety; secondary outcomes were (i) efficacy in alleviating the symptoms of FABD and (ii) efficacy in reducing SIBO, as assessed by hydrogen breath test (HBT).

RESULTS

No Adverse Events or Serious Unexpected Adverse Reactions were reported during the study. XG + PP showed a faster onset of action and a significant reduction in bloating and abdominal pain compared with simethicone. At Day 20, XG + PP drastically reduced abdominal girth when compared with simethicone, with an average reduction of 4.7 cm versus 1.8 cm. At Day 20, the XG + PP arm showed a significant reduction in HBT compared to baseline.

CONCLUSIONS

This study supports the evidence that FABD patients may benefit from a XG + PP-based treatment that acts on etiology and not just the symptoms.

Safe Subunit Green Vaccines Confer Robust Immunity and Protection against Mucosal Brucella Infection in Mice

Brucellosis is a zoonotic disease that causes significant negative impacts on the animal industry and affects over half a million people worldwide every year. The limited safety and efficacy of current animal brucellosis vaccines, combined with the lack of a licensed human brucellosis vaccine, have led researchers to search for new vaccine strategies to combat the disease. To this end, the present research aimed to evaluate the safety and efficacy of a green vaccine candidate that combines Brucella abortus S19 smooth lipopolysaccharide (sLPS) with Quillaja saponin (QS) or QS-Xyloglucan mix (QS-X) against mucosal brucellosis in BALB/C mice. The results of the study indicate that administering two doses of either sLPS-QS or sLPS-QS-X was safe for the animals, triggered a robust immune response, and enhanced protection following intranasal challenge with S19. Specifically, the vaccine combinations led to the secretion of IgA and IgG1 in the BALF of the immunized mice. We also found a mixed IgG1/IgG2a systemic response indicating evidence of both Th1 and Th2 activation, with a predominance of the IgG1 over the IgG2a. These candidates resulted in significant reductions in the bioburden of lung, liver, and spleen tissue compared to the PBS control group. The sLPS-QS vaccination had conferred the greatest protection, with a 130-fold reduction in Brucella burdens in lung and a 55.74-fold reduction in the spleen compared to PBS controls. Vaccination with sLPS-QS-X resulted in the highest reduction in splenic Brucella loads, with a 364.6-fold decrease in bacterial titer compared to non-vaccinated animals. The study suggests that the tested vaccine candidates are safe and effective in increasing the animals’ ability to respond to brucellosis via mucosal challenge. It also supports the use of the S19 challenge strain as a safe and cost-effective method for testing Brucella vaccine candidates under BSL-2 containment conditions.

Intervention and potential mechanism of non-starch polysaccharides from natural resources on ulcerative colitis: A review

Ulcerative colitis (UC) is a chronic inflammatory bowel disease of unknown etiology that affects the colon and rectum. It has evolved into a global burden due to the high incidence in developed countries and the highly-increased incidence in developing countries. Non-starch polysaccharides (NSPs) from natural resources, as a type of functional carbohydrates, have a significant therapeutic effect on UC because of their good anti-inflammatory and immunomodulatory activities. Based on the etiology and pathogenesis of UC, this review summarizes the intervention effects and mechanisms of NSPs in the prevention and treatment of UC. The results showed that NSPs can improve UC by protecting the intestinal mucosal barrier, regulating the immune response of the intestinal mucosa, and remodeling the intestinal flora and metabolites. These contents provide theoretical basis for the application of polysaccharides in the prevention and treatment of UC.

Intrarectal Xyloglucan Administration Reduces Disease Severity in the Dextran Sodium Sulfate Model of Mouse Colitis

Background

The pathophysiology of inflammatory bowel diseases remains poorly understood and treatment remains suboptimal for many patients. We hypothesize that the inflammatory milieu secondarily prolongs the injury and attenuates healing. We propose primary or adjuvant therapy with biocompatible adhesives to restore a barrier to protect submucosal structures, particularly stem cells.

Methods

We used the well-described mouse dextran sodium sulfate (DSS) model of colitis resembling human ulcerative colitis to test the therapeutic efficacy of intrarectal administration of the tamarind plant-derived xyloglucan (TXG) polymer adhesive which underwent extensive analytic characterization. Mice in control, DSS-only, TXG-only, and DSS + TXG groups were studied for gross (weight, blood in stool, length of colon) and multiple histologic parameters.

Results

Compared to DSS-only mice, TXG prevented the weight loss, occurrence of blood in the stool and colon shortening, with all those parameters not being statistically different from treatment naïve animals. Histologically, there was dramatic and highly statistically significant reduction in the total inflammatory index and protection from goblet cell loss, cellular infiltration, crypt abscess formation, epithelial erosion, granulation tissue, epithelial hyperplasia crypt irregularity and crypt loss. The TXG purity and characterization were established by nuclear magnetic resonance, infrared spectroscopy, differential scanning calorimetry, and texture analysis.

Conclusion

The striking attenuation of disease severity by intrarectal TXG use warrants future investigations of natural bioadhesives with well-established high safety profiles, and which could potentially be derivatized to include therapeutically active moieties for local drug delivery.

Interaction between polysaccharides and toll-like receptor 4: Primary structural role, immune balance perspective, and 3D interaction model hypothesis

Various structural types of polysaccharides are recognized by toll-like receptor 4 (TLR4). However, the mechanism of interaction between the polysaccharides with different structures and TLR4 is unclarified. This review summarized the primary structure of polysaccharides related to TLR4, mainly including molecular weight, monosaccharide composition, glycosidic bonds, functional groups, and branched-chain structure. The optimal primary structure for interacting with TLR4 was obtained by the statistical analysis. Besides, the dual-directional regulation of TLR4 signaling cascade by polysaccharides was also elucidated from an immune balance perspective. Finally, the 3D interaction model of polysaccharides to TLR4-myeloid differentiation factor 2 (MD2) complex was hypothesized according to the LPS-TLR4-MD2 dimerization model and the polysaccharides solution conformation. The essence of polysaccharides binding to TLR4-MD2 complex is a multivalent non-covalent bond interaction. All the arguments summarized in this review are intended to provide some new insights into the interaction between polysaccharides and TLR4.

COVID-19, cytokines, inflammation, and spices: How are they related?

BACKGROUND

Cytokine storm is the exaggerated immune response often observed in viral infections. It is also intimately linked with the progression of COVID-19 disease as well as associated complications and mortality. Therefore, targeting the cytokine storm might help in reducing COVID-19-associated health complications. The number of COVID-19 associated deaths (as of January 15, 2021; https://www.worldometers.info/coronavirus/) in the USA is high (1199/million) as compared to countries like India (110/million). Although the reason behind this is not clear, spices may have some role in explaining this difference. Spices and herbs are used in different traditional medicines, especially in countries such as India to treat various chronic diseases due to their potent antioxidant and anti-inflammatory properties.

AIM

To evaluate the literature available on the anti-inflammatory properties of spices which might prove beneficial in the prevention and treatment of COVID-19 associated cytokine storm.

METHOD

A detailed literature search has been conducted on PubMed for collecting information pertaining to the COVID-19; the history, origin, key structural features, and mechanism of infection of SARS-CoV-2; the repurposed drugs in use for the management of COVID-19, and the anti-inflammatory role of spices to combat COVID-19 associated cytokine storm.

KEY FINDINGS

The literature search resulted in numerous in vitro, in vivo and clinical trials that have reported the potency of spices to exert anti-inflammatory effects by regulating crucial molecular targets for inflammation.

SIGNIFICANCE

As spices are derived from Mother Nature and are inexpensive, they are relatively safer to consume. Therefore, their anti-inflammatory property can be exploited to combat the cytokine storm in COVID-19 patients. This review thus focuses on the current knowledge on the role of spices for the treatment of COVID-19 through suppression of inflammation-linked cytokine storm.

Present and Future Therapeutic Approaches to Barrier Dysfunction

There is converging and increasing evidence, but also uncertainty, for the role of abnormal intestinal epithelial barrier function in the origin and development of a growing number of human gastrointestinal and extraintestinal inflammatory disorders, and their related complaints. Despite a vast literature addressing factors and mechanisms underlying changes in intestinal permeability in humans, and its connection to the appearance and severity of clinical symptoms, the ultimate link remains to be established in many cases. Accordingly, there are no directives or clinical guidelines related to the therapeutic management of intestinal permeability disorders that allow health professionals involved in the management of these patients to carry out a consensus treatment based on clinical evidence. Instead, there are multiple pseudoscientific approaches and commercial propaganda scattered on the internet that confuse those affected and health professionals and that often lack scientific rigor. Therefore, in this review we aim to shed light on the different therapeutic options, which include, among others, dietary management, nutraceuticals and medical devices, microbiota and drugs, and epigenetic and exosomes-manipulation, through an objective evaluation of the scientific publications in this field. Advances in the knowledge and management of intestinal permeability will sure enable better options of dealing with this group of common disorders to enhance quality of life of those affected.

The Role of Purported Mucoprotectants in Dealing with Irritable Bowel Syndrome, Functional Diarrhea, and Other Chronic Diarrheal Disorders in Adults

Chronic diarrhea is a frequent presenting symptom, both in primary care medicine and in specialized gastroenterology units. It is estimated that more than 5% of the global population suffers from chronic diarrhea. and that about 40% of these subjects are older than 60 years. The clinician is frequently faced with the need to decide which is the best therapeutic approach for these patients. While the origin of chronic diarrhea is diverse, impairment of intestinal barrier function, dysbiosis. and mucosal micro-inflammation are being increasingly recognized as underlying phenomena characterizing a variety of chronic diarrheal diseases. In addition to current pharmacological therapies, there is growing interest in alternative products such as mucoprotectants, which form a mucoadhesive film over the epithelium to reduce and protect against the development of altered intestinal permeability, dysbiosis, and mucosal micro-inflammation. This manuscript focuses on chronic diarrhea in adults, and we will review recent evidence on the ability of these natural compounds to improve symptoms associated with chronic diarrhea and to exert protective effects for the intestinal barrier.

A comprehensive study on 2D, 3D and solid tumor environment to explore a multifunctional biogenic nanoconjugate

Emergence of nanotechnology created a drastic change in the field of cancer therapy due to their unique features in drug delivery and imaging. Polysaccharide based nanoparticles have received extensive attention in recent years as promising nanoparticle mediated drug delivery systems. Polysaccharides are endorsed with versatile merits including high drug encapsulation efficiency, efficient drug protection against chemical or enzymatic degradation, unique ability to create a controlled release and cellular internalization. In the current study, we have fabricated doxorubicin-loaded carboxymethylated PST001 coated iron oxide nanoparticles (DOX@CM-PST-IONPs) for better management of cancer. CM-PST coated iron oxide nanoparticles co-encapsulated with chemotherapeutic drug doxorubicin, can be utilized for targeted drug delivery. Biocompatible and non-toxic nanoconjugates was found to be effective in both 2-D and 3-D cell culture system with efficient cancer cell internalization. The bench-marked potential of CM-PIONPs to produce reactive oxygen species makes it a noticeable drug delivery system to compact neoplasia. These nanoconjugates can lay concrete on a better way for the elimination of cancer spheroids and tumor burden.

Nanostructured Cellulose-Gellan-Xyloglucan-Lysozyme Dressing Seeded with Mesenchymal Stem Cells for Deep Second-Degree Burn Treatment

PURPOSE

In deep burns, wound contraction and hypertrophic scar formation can generate functional derangement and debilitation of the affected part. In order to improve the quality of healing in deep second-degree burns, we developed a new treatment in a preclinical model using nanostructured membranes seeded with mesenchymal stem cells (MSCs).

METHODS

Membranes were obtained by reconstitution of bacterial cellulose (reconstituted membrane [RM]) and produced by a dry-cast process, then RM was incorporated with 10% tamarind xyloglucan plus gellan gum 1:1 and 10% lysozyme (RMGT-LZ) and with 10% gellan gum and 10% lysozyme (RMG-LZ). Membrane hydrophobic/hydrophilic characteristics were investigated by static/dynamic contact-angle measurements. They were cultivated with MSCs, and cell adhesion, proliferation, and migration capacity was analyzed with MTT assays. Morphological and topographic characteristics were analyzed by scanning electron microscopy. MSC patterns in flow cytometry and differentiation into adipocytes and osteocytes were checked. In vivo assays used RMG-LZ and RMGT-LZ (with and without MSCs) in Rattus norvegicus rats submitted to burn protocol, and histological sections and collagen deposits were analyzed and immunocytochemistry assay performed.

RESULTS

In vitro results demonstrated carboxyl and amine groups made the membranes moderately hydrophobic and xyloglucan inclusion decreased wettability, favoring MSC adhesion, proliferation, and differentiation. In vivo, we obtained 40% and 60% reduction in acute/chronic inflammatory infiltrates, 96% decrease in injury area, increased vascular proliferation and collagen deposition, and complete epithelialization after 30 days. MSCs were detected in burned tissue, confirming they had homed and proliferated in vivo.

CONCLUSION

Nanostructured cellulose-gellan-xyloglucan-lysozyme dressings, especially when seeded with MSCs, improved deep second-degree burn regeneration.

Trioxolone Methyl, a Novel Cyano Enone-Bearing 18βH-Glycyrrhetinic Acid Derivative, Ameliorates Dextran Sulphate Sodium-Induced Colitis in Mice

Semi-synthetic triterpenoids, bearing cyano enone functionality in ring A, are considered to be novel promising therapeutic agents with complex inhibitory effects on tissue damage, inflammation and tumor growth. Previously, we showed that the cyano enone-containing 18βH-glycyrrhetinic acid derivative soloxolone methyl (SM) effectively suppressed the inflammatory response of macrophages in vitro and the development of influenza A-induced pneumonia and phlogogen-stimulated paw edema in vivo. In this work, we reported the synthesis of a novel 18βH-glycyrrhetinic acid derivative trioxolone methyl (TM), bearing a 2-cyano-3-oxo-1(2)-en moiety in ring A and a 12,19-dioxo-9(11),13(18)-dien moiety in rings C, D, and E. TM exhibited a high inhibitory effect on nitric oxide (II) production by lipopolysaccharide-stimulated J774 macrophages in vitro and dextran sulfate sodium (DSS)-induced colitis in mice, displaying higher anti-inflammatory activity in comparison with SM. TM effectively suppressed the DSS-induced epithelial damage and inflammatory infiltration of colon tissue, the hyperproduction of colonic neutral mucin and TNFα and increased glutathione synthesis. Our in silico analysis showed that Akt1, STAT3 and dopamine receptor D2 can be considered as mediators of the anti-colitic activity of TM. Our findings provided valuable information for a better understanding of the anti-inflammatory activity of cyano enone-bearing triterpenoids and revealed TM as a promising anti-inflammatory candidate.

Interplay Between Human Gut Bacteria Escherichia coli and Lactobacillus mucosae in the Occurrence of Neuropsychiatric Disorders in Mice

To understand the roles of human gut bacteria in the occurrence of neuropsychiatric disorders, we isolated inflammatory Escherichia coli K1 and anti-inflammatory Lactobacillus mucosae from healthy human feces and examined their effects on the occurrence of altered microbiota, cognitive decline, and depression in mice. Oral gavage of Escherichia coli K1 caused colitis, cognitive decline, and depression in mice in the elevated plus maze, tail suspension, and forced swimming tasks. However, NK41 treatment reduced K1-induced cognitive decline and anxiety/depression. Furthermore, NK41 treatment increased K1-suppressed brain-derived neurotrophic factor (BDNF) expression and BDNF⁺/NeuN⁺ cell population and suppressed K1-induced NF-κB activation and LPS⁺/Iba1⁺ and NF-κB⁺/Iba1⁺ (microglial) cell populations in the hippocampus. NK41 treatment also suppressed K1-induced TNF-α and LPS levels in the blood and TNF-α expression, myeloperoxidase activity, NF-κB⁺/CD11c⁺ and CD11b⁺/CD11c⁺ cell populations in the colon. Furthermore, NK41 treatment decreased K1-induced colonic MUC2 expression, gut Proteobacteria population, and fecal LPS levels and modified the bacterial abundance related to polysaccharide breaking and biosynthesis. In conclusion, the overgrowth of inflammatory bacteria such as Escherichia coli in the gastrointestinal tract can cause neuropsychiatric disorders with gut microbiota alteration and the superiority of anti-inflammatory bacteria such as Lactobacillus mucosae can alleviate neuropsychiatric disorders with the attenuation of altered microbiota.

Alpha7 Nicotinic Acetylcholine Receptor Alleviates Inflammatory Bowel Disease Through Induction of AMPK-mTOR-p70S6K-Mediated Autophagy

Alpha7 nicotinic acetylcholine receptor (α7nAChR) has been reported to be protective in several kinds of disorders through inflammatory suppression. Here, we investigated the role of α7nAChR in inflammatory bowel disease (IBD) on α7nAChR deficient mice (α7nAChR^-/-) and the wild-type mice (α7nAChR^+/+). Three percent dextran sulfate sodium (DSS) was used for the creation of IBD mice model and lipopolysaccharides (LPS)/DSS as an inflammatory stressor in murine bone marrow-derived macrophages (BMDMs). The severity of IBD was determined and HE staining as well as enzyme-linked immunosorbent assay (ELISA) and real-time PCR were used to detect the level of inflammatory activation. Western blot was used to determine the levels of autophagy-related proteins. Transmission electron microscopy and mRFP-GFP-LC3 plasmid were applied to determine the levels of autophagy. We demonstrated that deficiency in α7nAChR produced a detrimental effect on IBD severity and inflammatory reaction in DSS-induced colitis models. Those effects were led to via autophagy dysfunction. α7nAChR deficiency attenuated the protective and anti-inflammatory effect of autophagy inducer in IBD mice and BMDMs challenged with LPS/DSS. The alleviative effect of activating α7nAChR was attenuated through inhibiting adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)-mediated signaling. In conclusion, α7nAChR contributes to alleviate IBD through the induction of AMPK-mammalian target of rapamycin rabbit (mTOR)-p70 ribosomal protein S6 kinase (p70S6K)-mediated autophagy, thus providing a novel target for the treatment of IBD.

The profiling of bioactives in Akebia trifoliata pericarp and metabolites, bioavailability and in vivo anti-inflammatory activities in DSS-induced colitis mice

The fruit of Akebia trifoliata is popular in Asia, but researches concerning the phytochemicals of A. trifoliate pericarp extract (APE) and their metabolites, bioavailability, metabolism and anti-inflammatory activity in vivo are less known. In the present study, the chemical constituents of APE and their metabolites of rats after oral administration were identified using UPLC-LTQ-Orbitrap-MS/MS. A total of 18 compounds were tentatively characterized in APE, while 8 original compounds and 8 metabolites were observed in plasma, and 10 original compounds and 39 metabolites were detected in urine. Deglycosylation, glucuronidation, methylation and sulfation were the reactions that mainly occurred in the metabolism in vivo. Meanwhile, APE supplementation decreased dextran sulphate sodium (DSS)-induced colitis in mice, ameliorating epithelial barrier disruption, suppressing the proliferation and infiltration of immune cells, modulating the secretion of nitric oxide (NO) and prostaglandin E2 (PGE2), decreasing the expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) as well as regulating oxidative stress in vivo. The results suggested that APE triterpenoids and their metabolites as major contributors to anti-inflammatory activities, providing a scientific basis for the use of APE as a functional food to ameliorate colon health in humans.