A probiotic complex, rosavin, zinc, and prebiotics ameliorate intestinal inflammation in an acute colitis mouse model

Zinc and Inflammatory Bowel Disease: From Clinical Study to Animal Experiment

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract (GI) with a high incidence rate globally, and IBD patients are often accompanied by zinc deficiency. This review aims to summarize the potential therapeutic value of zinc supplementation in IBD clinical patients and animal models. Zinc supplementation can relieve the severity of IBD especially in patients with zinc deficiency. The clinical severity of IBD were mainly evaluated through some scoring methods involving clinical performance, endoscopic observation, blood biochemistry, and pathologic biopsy. Through conducting animal experiments, it has been found that zinc plays an important role in alleviating clinical symptoms and improving pathological lesions. In both clinical observation and animal experiment of IBD, the therapeutic mechanisms of zinc interventions have been found to be related to immunomodulation, intestinal epithelial repair, and gut microbiota's balance. Furthermore, the antioxidant activity of zinc was clarified in animal experiment. Appropriate zinc supplementation is beneficial for IBD therapy, and the present evidence highlights that alleviating zinc-deficient status can effectively improve the severity of clinical symptoms in IBD patients and animal models.

Protective Effect of Rosavin Against Intestinal Epithelial Injury in Colitis Mice and Intestinal Organoids

Introduction

Rhodiola species have been utilized as functional foods in Asia and Europe for promoting health. Research has demonstrated that Rhodiola has the potential to alleviate inflammatory bowel disease (IBD) in animal models. However, the specific active components and the underlying mechanism for ameliorating intestinal damage remain unclear. This study aims to explore the relieving effect of Rosavin (Rov), a known active constituent of Rhodiola, in IBD and the regulatory mechanisms.

Methods

The therapeutic effect of Rov was evaluated using a murine model of acute colitis induced by dextran sulfate sodium salt (DSS). Inflammatory cytokines and neutrophil activation markers were measured by corresponding kits. Immunohistochemistry, immunofluorescence, TUNEL, and EdU assays were applied to investigate the tight conjunction proteins expression, epithelial marker expression, number of apoptotic cells, and epithelial proliferation, respectively. The protection effect of Rov on gut epithelial injury was assessed using TNF-α-induced intestinal organoids. Additinally, RNA sequencing was applied to observe the genetic alteration profile in these intestinal organoids.

Results

Oral administration of Rov significantly attenuated weight loss and restored colon length in mice. Notably, Rov treatment led to decreased levels of pro-inflammatory cytokines and neutrophil activation markers while increasing anti-inflammatory factors. Importantly, Rov restored intestinal despair by increasing the number of Lgr5+ stem cells, Lyz1+ Paneth cells and Muc2+ goblet cells in intestines of colitis mice, displaying reduced epithelial apoptosis and recovered barrier function. In TNF-α-induced intestinal organoids, Rov facilitated epithelial cell differentiation and protected against TNF-α-induced damage. RNA sequencing revealed upregulation in the gene expression associated with epithelial cells (including Lgr5+, Lyz1+ and Muc2+ cells) proliferation and defensin secretion, unveiling the protective mechanisms of Rov on the intestinal epithelial barrier.

Discussion

Rov holds potential as a natural prophylactic agent against IBD, with its protective action on the intestinal epithelium being crucial for its therapeutic efficacy.

Therapeutic Promises of Bioactive Rosavin: A Comprehensive Review with Mechanistic Insight

Rosavin is an alkylbenzene diglycoside primarily found in Rhodiola rosea (L.), demonstrating various pharmacological properties in a number of preclinical test systems. This study focuses on evaluating the pharmacological effects of rosavin and the underlying molecular mechanisms based on different preclinical and non-clinical investigations. The findings revealed that rosavin has anti-microbial, antioxidant, and different protective effects, including neuroprotective effects against various neurodegenerative ailments such as mild cognitive disorders, neuropathic pain, depression, and stress, as well as gastroprotective, osteoprotective, pulmoprotective, and hepatoprotective activities. This protective effect of rosavin is due to its capability to diminish inflammation and oxidative stress. The compound also manifested anticancer properties against various cancer via exerting cytotoxicity, apoptotic cell death, arresting the different phases (G0/G1) of the cancerous cell cycle, inhibiting migration, and invading other organs. Rosavin also regulated MAPK/ERK signaling pathways to exert suppressing effect of cancer cell. However, because of its high-water solubility, which lowers its permeability, the phytochemical has low oral bioavailability. The compound's relevant drug likeness was evaluated by the in silico ADME, revealing appropriate drug likeness. We suggest more extensive investigation and clinical studies to determine safety, efficacy, and human dose to establish the compound as a reliable therapeutic agent.

Fibrostenosing Crohn's Disease: Pathogenetic Mechanisms and New Therapeutic Horizons

Bowel strictures are well recognized as one of the most severe complications in Crohn's disease, with variable impacts on the prognosis and often needing surgical or endoscopic treatment. Distinguishing inflammatory strictures from fibrotic ones is of primary importance due to the different therapeutic approaches required. Indeed, to better understand the pathogenesis of fibrosis, it is crucial to investigate molecular processes involving genetic factors, cytokines, alteration of the intestinal barrier, and epithelial and endothelial damage, leading to an increase in extracellular matrix synthesis, which ultimately ends in fibrosis. In such a complex mechanism, the gut microbiota also seems to play a role. A better comprehension of molecular processes underlying bowel fibrosis, in addition to radiological and histopathological findings, has led to the identification of high-risk patients for personalized follow-up and testing of new therapies, primarily in preclinical models, targeting specific pathways involving Transforming Growth Factor-β, interleukins, extracellular matrix balance, and gut microbiota. Our review aims to summarize current evidence about molecular factors involved in intestinal fibrosis' pathogenesis, paving the way for potential diagnostic biomarkers or anti-fibrotic treatments for stricturing Crohn's disease.

Gut Microbiota Metabolites: Unveiling Their Role in Inflammatory Bowel Diseases and Fibrosis

In recent years, there has been a growing focus on the intricate interplay between the gut microbiota and host health, specifically in the context of inflammatory bowel diseases (IBDs). The gut microbiota produces a diverse array of metabolites, influencing the host's immune response and tissue homeostasis. Noteworthy metabolites, such as short-chain fatty acids, bile acids, and indoles, exert significant effects on intestinal inflammation and fibrosis. This review integrates current research findings to clarify the mechanisms through which gut microbiota metabolites contribute to the progression of IBD and fibrosis, offering insights into potential therapeutic targets and strategies for managing these intricate gastrointestinal conditions. The unraveling of the complex relationship between gut microbiota metabolites and inflammatory processes holds promise for the development of targeted interventions that could lead to more effective and personalized treatment approaches for individuals affected by IBD and subsequent intestinal fibrosis.

The Role of Rosavin in the Pathophysiology of Bone Metabolism

Rosavin, a phenylpropanoid in Rhodiola rosea's rhizome, and an adaptogen, is known for enhancing the body's response to environmental stress. It significantly affects cellular metabolism in health and many diseases, particularly influencing bone tissue metabolism. In vitro, rosavin inhibits osteoclastogenesis, disrupts F-actin ring formation, and reduces the expression of osteoclastogenesis-related genes such as cathepsin K, calcitonin receptor (CTR), tumor necrosis factor receptor-associated factor 6 (TRAF6), tartrate-resistant acid phosphatase (TRAP), and matrix metallopeptidase 9 (MMP-9). It also impedes the nuclear factor of activated T-cell cytoplasmic 1 (NFATc1), c-Fos, the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and mitogen-activated protein kinase (MAPK) signaling pathways and blocks phosphorylation processes crucial for bone resorption. Moreover, rosavin promotes osteogenesis and osteoblast differentiation and increases mouse runt-related transcription factor 2 (Runx2) and osteocalcin (OCN) expression. In vivo studies show its effectiveness in enhancing bone mineral density (BMD) in postmenopausal osteoporosis (PMOP) mice, restraining osteoclast maturation, and increasing the active osteoblast percentage in bone tissue. It modulates mRNA expressions by increasing eukaryotic translation elongation factor 2 (EEF2) and decreasing histone deacetylase 1 (HDAC1), thereby activating osteoprotective epigenetic mechanisms, and alters many serum markers, including decreasing cross-linked C-telopeptide of type I collagen (CTX-1), tartrate-resistant acid phosphatase 5b (TRACP5b), receptor activator for nuclear factor κ B ligand (RANKL), macrophage-colony-stimulating factor (M-CSF), and TRAP, while increasing alkaline phosphatase (ALP) and OCN. Additionally, when combined with zinc and probiotics, it reduces pro-osteoporotic matrix metallopeptidase 3 (MMP-3), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α), and enhances anti-osteoporotic interleukin 10 (IL-10) and tissue inhibitor of metalloproteinase 3 (TIMP3) expressions. This paper aims to systematically review rosavin's impact on bone tissue metabolism, exploring its potential in osteoporosis prevention and treatment, and suggesting future research directions.

Protective effect of Lizhong Pill on nonsteroidal anti-inflammatory drug-induced gastric mucosal injury in rats: Possible involvement of TNF and IL-17 signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional Chinese medicine formula Lizhong Pill (LZP) and its herbal constituents are frequently utilized in Asian (China, Saudi Arabia, India, Japan, etc.) and some European (Russia, Sweden, UK, etc.) nations to treat various gastrointestinal ailments.

AIM OF THE STUDY

This study aimed to investigate the protective impact and potential mechanism of LZP against indomethacin (IND)-induced gastric mucosal injury in rats.

MATERIAL AND METHODS

Using a biochemical kit, we investigated the levels of superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) in rat serum, as well as pepsin in rat stomach tissue, using an IND-induced rat model of gastric mucosal injury. Various imaging tools, including HE staining, scanning electron microscopy (SEM), and transmission electron microscopy (TEM), were used to examine the gastric mucosa's surface morphology and ultrastructure. Furthermore, molecular docking was employed to predict the binding capacity of the primary bioactive components of LZP to the critical molecular protein targets in the IL-17 and TNF signaling pathways. At the same time, immunofluorescence was used to determine the protein expressions of CASP3, VCAM1, MAPK15, MMP3, IL-17RA, and TNFR1.

RESULTS

The present study demonstrates that LZP (3.75 and 7.50 g/kg) significantly reduces the gastric mucosal injury index induced by IND. This effect is evidenced by the improved morphology, surface, and structure of the gastric mucosa, as determined by HE, SEM, and TEM findings. Additionally, 3.75 and 7.50 g/kg LZP intervention significantly increased SOD and CAT contents and inhibited pepsin and GST activities. Molecular docking analysis revealed that the small molecular components of LZP can bind spontaneously to crucial proteins involved in the IL-17 and TNF signaling pathways, including MAPK15, MMP3, VCAM1, and CASP3. The immunofluorescence findings proved that LZP (3.75 and 7.50 g/kg) can inhibit the protein expressions of MAPK15, MMP3, VCAM1, CASP3, IL-17RA, and TNFR1.

CONCLUSIONS

Our investigation findings demonstrate that LZP can potentially ameliorate IND-induced damage to the gastric mucosa by inhibiting IL-17 and TNF signaling pathways. These results offer encouraging support for using alternative medicine to manage drug-induced gastric mucosal injury.

Emu Oil and zinc monoglycerolate independently reduce disease severity in a rat model of ulcerative colitis

Ulcerative colitis is characterized by colonic inflammation. Previously, Emu Oil protected the intestine against experimentally-induced inflammatory intestinal disorders. Zinc monoglycerolate (ZMG) polymer, formed by heating zinc oxide with glycerol, demonstrated anti-inflammatory and wound healing properties. We aimed to determine whether ZMG, alone or in combination with Emu Oil, could reduce acute colitis severity in rats. Male Sprague Dawley rats (n = 8/group) were orally-administered either vehicle, ZMG, Emu Oil (EO) or ZMG combined with EO (ZMG/EO) daily. Rats were provided ad libitum access to drinking water (Groups 1-4) or dextran sulphate sodium (DSS; 2%w/v; Groups 5-8) throughout the trial (days 0-5) before euthanasia on day 6. Disease activity index, crypt depth, degranulated mast cells (DMCs) and myeloperoxidase (MPO) activity were assessed. p < 0.05 was considered significant. DSS increased disease severity (days 3-6) compared to normal controls (p < 0.05). Importantly, in DSS-administered rats, ZMG/EO (day 3) and ZMG (day 6) reduced disease activity index compared to controls (p < 0.05). Following DSS consumption, distal colonic crypts lengthened (p < 0.01), occurring to a greater extent with EO compared to ZMG and ZMG/EO (p < 0.001). DSS increased colonic DMC numbers compared to normal controls (p < 0.001); an effect decreased only by EO (p < 0.05). Colonic MPO activity increased following DSS consumption (p < 0.05); notably, ZMG, EO and ZMG/EO treatments decreased MPO activity compared to DSS controls (p < 0.001). EO, ZMG and ZMG/EO did not impact any parameter in normal animals. Emu Oil and ZMG independently decreased selected indicators of colitic disease severity in rats; however, the combination did not reveal any additional benefit.

Rosavin: Research Advances in Extraction and Synthesis, Pharmacological Activities and Therapeutic Effects on Diseases of the Characteristic Active Ingredients of Rhodiola rosea L

Rhodiola rosea L. (RRL) is a popular plant in traditional medicine, and Rosavin, a characteristic ingredient of RRL, is considered one of the most important active ingredients in it. In recent years, with deepening research on its pharmacological actions, the clinical application value and demand for Rosavin have been steadily increasing. Various routes for the extraction and all-chemical or biological synthesis of Rosavin have been gradually developed for the large-scale production and broad application of Rosavin. Pharmacological studies have demonstrated that Rosavin has a variety of biological activities, including antioxidant, lipid-lowering, analgesic, antiradiation, antitumor and immunomodulation effects. Rosavin showed significant therapeutic effects on a range of chronic diseases, including neurological, digestive, respiratory and bone-related disorders during in vitro and vivo experiments, demonstrating the great potential of Rosavin as a therapeutic drug for diseases. This paper gives a comprehensive and insightful overview of Rosavin, focusing on its extraction and synthesis, pharmacological activities, progress in disease-treatment research and formulation studies, providing a reference for the production and preparation, further clinical research and applications of Rosavin in the future.

Rosavin regulates bone homeostasis through HDAC1-induced epigenetic regulation of EEF2

Bioactive constituents from Rhodiola rosea L. show a myriad of pharmacological effects on diverse diseases. Rosavin has been linked to reduced osteoclastogenesis, while its role in regulating osteogenesis remains unclear. The present study investigated whether and how Rosavin alleviates ovariectomy (OVX)-induced osteoporosis (OP) in mice. Rosavin had a therapeutic effect on OP in ovariectomized mice and inhibited osteoclast viability and promoted osteoblast viability. Integrated transcriptome sequencing, GO enrichment analysis, and PPI network construction revealed that the HDAC1/EEF2 axis was an important axis of gene action for Rosavin treatment. Mechanistically, HDAC1 suppressed EEF2 expression through histone deacetylation. Rescue experiments exhibited that HDAC1 promoted osteoclast viability, while EEF2 reversed the action of HDAC1 to restore bone homeostasis. In mice with OP, HDAC1 mitigated the effects of Rosavin, resulting in enhanced bone resorption and diminished bone formation, while EEF2 contributed to reduced bone resorption and elevated bone formation in mice. NF-κB and MAPK pathways were inhibited by Rosavin, enhanced by HDAC1, and blocked again by EEF2. To summarize, our results proved that Rosavin maintained bone homeostasis in OP via regulation of histone acetylation of EEF2, thus playing a key role as a therapeutic candidate for OP treatment.

Biomarkers of ulcerative colitis disease activity CXCL1, CYP2R1, LPCAT1, and NEU4 and their relationship to immune infiltrates

The diagnosis and assessment of ulcerative colitis (UC) poses significant challenges, which may result in inadequate treatment and a poor prognosis for patients. This study aims to identify potential activity biomarkers for UC and investigate the role of infiltrating immune cells in the disease. To perform gene set enrichment analysis, we utilized the cluster profiler and ggplot2 packages. Kyoto encyclopedia of genes and genomes was used to analyze degenerate enrichment genes. Significant gene set enrichment was determined using the cluster profiler and ggplot2 packages. Additionally, quantitative PCR (qRT-PCR) was employed to validate the expression of each marker in the ulcerative colitis model. We identified 651 differentially expressed genes (DEGs) and further investigated potential UC activity biomarkers. Our analysis revealed that CXCL1 (AUC = 0.710), CYP2R1 (AUC = 0.863), LPCAT1 (AUC = 0.783), and NEU4 (AUC = 0.833) were promising activity markers for the diagnosis of UC. Using rat DSS model, we validated these markers through qRT-PCR, which showed statistically significant differences between UC and normal colon mucosa. Infiltrating immune cell analysis indicated that M1 macrophages, M2 macrophages, activated dendritic cells (DCs), and neutrophils played crucial roles in the occurrence and progression of UC. Moreover, the activity markers exhibited varying degrees of correlation with activated memory CD4 T cells, M0 macrophages, T follicular helper cells, memory B cells, and activated DCs. The potential diagnostic genes for UC activity, such as CXCL1, CYP2R1, LPCAT1, and NEU4, as well as the infiltration of immune cells, may contribute to the pathogenesis and progression of UC.

Highlights on two decades with microbiota and inflammatory bowel disease from etiology to therapy

Inflammatory Bowel diseases (IBDs) constitute a complex panel of disorders characterized with chronic inflammation affecting the alimentary canal along with extra intestinal manifestations. Its exact etiology is still unknown; however, it seems to be the result of uncharacterized environmental insults in the intestine and their immunological consequences along with dysbiosis, in genetically predisposed individuals. It was the main target of our team since 2002 to explore the etiology of IBD and the related role of bacteria. For almost two decades, our laboratory, among others, has been involved in the reciprocal interaction between the host gastrointestinal lining and the homing microbiota. In the first decade, the attention of scientists focused on the possible role of enteropathogenic E. coli and its relationship to the mechanistic pathways involved in IBD induced in both rats and mice by chemicals like Iodoacetamide, Dextran Sodium Sulfate, Trinitrobenzene, thus linking microbial alteration to IBD pathology. A thorough characterization of the various models was the focus of research in addition to exploring how to establish an active homeostatic composition of the commensal microbiota, including its wide diversity by restoration of gut microbiota by probiotics and moving from dysbiosis to eubiosis. In the last six years and in order to effectively translate such findings into clinical practice, it was critical to explore their relationship to colorectal cancer CRC both in solid tumors and chemically induced CRC. It was also critical to explore the degree of intestinal dysbiosis and linking to IBD, CRC and diabetes. Remarkably, the active mechanistic pathways were proposed as well as the role of microbiota or bacterial metabolites involved. This review covers two decades of investigations in our laboratory and sheds light on the different aspects of the relationship between microbiota and IBD with an emphasis on dysbiosis, probiotics and the multiple mechanistic pathways involved.

The involvement of TH17 cells in the pathogenesis of IBD

The pathogenesis of inflammatory bowel disease (IBD) is still unclear. Immune dysfunction may play a key role in the pathogenesis of IBD, in which the role of CD4⁺ T helper (Th) cells is particularly important. Th17 cells are a major component of CD4⁺ T cells, and their differentiation is regulated by a variety of extracellular signals, transcription factors, RNA, and posttranslational modifications. Th17 cells specifically produce IL-17 and play an important role in the protection of mucous membranes and epithelial tissues against infection by extracellular microbes. However, when immune regulation is dysfunctional, Th17 cells abnormally proliferate and produce large amounts of proinflammatory cytokines that can recruit other inflammatory cells, which together induce abnormal immune responses and result in the development of many autoimmune diseases. In recent years, studies have confirmed that Th17 cells play an important role in the pathogenesis of IBD, which makes it a possible target for IBD therapy. This article reviews the recent progress of Th17 cells involved in the pathogenesis of IBD and its targeted therapy.

Pretreatment with rosavin attenuates PM2.5-induced lung injury in rats through antiferroptosis via PI3K/Akt/Nrf2 signaling pathway

Inflammation and oxidative stress caused by fine particulate matter (PM2.5) increase the incidence and mortality rates of respiratory disorders. Rosavin is the main chemical component of Rhodiola plants, which exerts anti-oxidative and antiinflammatory effects. In this research, the potential therapeutic effect of rosavin was investigated by the PM2.5-induced lung injury rat model. Rats were instilled with PM2.5 (7.5 mg/kg) suspension intratracheally, while rosavin (50 mg/kg, 100 mg/kg) was delivered by intraperitoneal injection before the PM2.5 injection. It was observed that rosavin could prevent lung injury caused by PM2.5. PM2.5 showed obvious ferroptosis-related ultrastructural alterations, which were significantly corrected by rosavin. The pretreatment with rosavin downregulated the levels of tissue iron, malondialdehyde, and 4-hydroxynonenal, and increased the levels of glutathione. The expression of nuclear factor E2-related factor 2 (Nrf2) was upregulated by rosavin, together with other ferroptosis-related proteins. RSL3, a specific ferroptosis agonist, reversed the beneficial impact of rosavin. The network pharmacology approach predicted the activation of rosavin on the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway. LY294002, a potent PI3K inhibitor, decreased the upregulation of Nrf2 induced by rosavin. In conclusion, rosavin prevented lung injury induced by PM2.5 stimulation and suppressed ferroptosis via upregulating PI3K/Akt/Nrf2 signaling pathway.

The Double Game Played by Th17 Cells in Infection: Host Defense and Immunopathology

T-helper 17 (Th17) cells represent a subpopulation of CD4+ T lymphocytes that play an essential role in defense against pathogens. Th17 cells are distinguished from Th1 and Th2 cells by their ability to produce members of the interleukin-17 (IL-17) family, namely IL-17A and IL-17F. IL-17 in turn induces several target cells to synthesize and release cytokines, chemokines, and metalloproteinases, thereby amplifying the inflammatory cascade. Th17 cells reside predominantly in the lamina propria of the mucosa. Their main physiological function is to maintain the integrity of the mucosal barrier against the aggression of infectious agents. However, in an appropriate inflammatory microenvironment, Th17 cells can transform into immunopathogenic cells, giving rise to inflammatory and autoimmune diseases. This review aims to analyze the complex mechanisms through which the interaction between Th17 and pathogens can be on the one hand favorable to the host by protecting it from infectious agents, and on the other hand harmful, potentially generating autoimmune reactions and tissue damage.

Inflammatory bowel disease therapeutic strategies by modulation of the microbiota: how and when to introduce pre-, pro-, syn-, or postbiotics?

Inflammatory bowel diseases (IBD), a heterogeneous group of inflammatory conditions that encompass both ulcerative colitis and Crohn's disease, represent a major public health concern. The etiology of IBD is not yet fully understood and no cure is available, with current treatments only showing long-term effectiveness in a minority of patients. A need to increase our knowledge on IBD pathophysiology is growing, to define preventive measures, to improve disease outcome, and to develop new effective and lasting treatments. IBD pathogenesis is sustained by aberrant immune responses, associated with alterations of the intestinal epithelial barrier (IEB), modifications of the enteric nervous system, and changes in microbiota composition. Currently, most of the treatments target the inflammation and the immune system, but holistic approaches targeting lifestyle and diet improvements are emerging. As dysbiosis is involved in IBD pathogenesis, pre-, pro-, syn-, and postbiotics are used/tested to reduce the inflammation or strengthen the IEB. The present review will resume these works, pointing out the stage of life, the duration, and the environmental conditions that should go along with microbiota or microbiota-derived treatments.

The Activity of Prebiotics and Probiotics in Hepatogastrointestinal Disorders and Diseases Associated with Metabolic Syndrome

The components of metabolic syndrome (MetS) and hepatogastrointestinal diseases are widespread worldwide, since many factors associated with lifestyle and diet influence their development and correlation. Due to these growing health problems, it is necessary to search for effective alternatives for prevention or adjuvants in treating them. The positive impact of regulated microbiota on health is known; however, states of dysbiosis are closely related to the development of the conditions mentioned above. Therefore, the role of prebiotics, probiotics, or symbiotic complexes has been extensively evaluated; the results are favorable, showing that they play a crucial role in the regulation of the immune system, the metabolism of carbohydrates and lipids, and the biotransformation of bile acids, as well as the modulation of their central receptors FXR and TGR-5, which also have essential immunomodulatory and metabolic activities. It has also been observed that they can benefit the host by displacing pathogenic species, improving the dysbiosis state in MetS. Current studies have reported that paraprobiotics (dead or inactive probiotics) or postbiotics (metabolites generated by active probiotics) also benefit hepatogastrointestinal health.

Gut Microbiota, Macrophages and Diet: An Intriguing New Triangle in Intestinal Fibrosis

Intestinal fibrosis is a common complication in inflammatory bowel disease (IBD) without specific treatment. As macrophages are the key actors in inflammatory responses and the wound healing process, they have been extensively studied in chronic diseases these past decades. By their exceptional ability to integrate diverse stimuli in their surrounding environment, macrophages display a multitude of phenotypes to underpin a broad spectrum of functions, from the initiation to the resolution of inflammation following injury. The hypothesis that distinct macrophage subtypes could be involved in fibrogenesis and wound healing is emerging and could open up new therapeutic perspectives in the treatment of intestinal fibrosis. Gut microbiota and diet are two key factors capable of modifying intestinal macrophage profiles, shaping their specific function. Defects in macrophage polarisation, inadequate dietary habits, and alteration of microbiota composition may contribute to the development of intestinal fibrosis. In this review, we describe the intriguing triangle between intestinal macrophages, diet, and gut microbiota in homeostasis and how the perturbation of this discreet balance may lead to a pro-fibrotic environment and influence fibrogenesis in the gut.

Therapeutic Targeting of Intestinal Fibrosis in Crohn's Disease

Intestinal fibrosis is one of the most threatening complications of Crohn’s disease. It occurs in more than a third of patients with this condition, is associated with increased morbidity and mortality, and surgery often represents the only available therapeutic option. The mechanisms underlying intestinal fibrosis are partly known. Studies conducted so far have shown a relevant pathogenetic role played by mesenchymal cells (especially myofibroblasts), cytokines (e.g., transforming growth factor-β), growth factors, microRNAs, intestinal microbiome, matrix stiffness, and mesenteric adipocytes. Further studies are still necessary to elucidate all the mechanisms involved in intestinal fibrosis, so that targeted therapies can be developed. Although several pre-clinical studies have been conducted so far, no anti-fibrotic therapy is yet available to prevent or reverse intestinal fibrosis. The aim of this review is to provide an overview of the main therapeutic targets currently identified and the most promising anti-fibrotic therapies, which may be available in the near future.

NTPDase8 protects mice from intestinal inflammation by limiting P2Y6 receptor activation: identification of a new pathway of inflammation for the potential treatment of IBD

OBJECTIVE

Nucleotides are danger signals that activate inflammatory responses via binding P2 receptors. The nucleoside triphosphate diphosphohydrolase-8 (NTPDase8) is an ectonucleotidase that hydrolyses P2 receptor ligands. We investigated the role of NTPDase8 in intestinal inflammation.

DESIGN

We generated NTPDase8-deficient (Entpd8-/-) mice to define the role of NTPDase8 in the dextran sodium sulfate (DSS) colitis model. To assess inflammation, colons were collected and analysed by histopathology, reverse transcriptase-quantitative real-time PCR (RT-qPCR) and immunohistochemistry. P2 receptor expression was analysed by RT-qPCR on primary intestinal epithelium and NTPDase8 activity by histochemistry. The role of intestinal P2Y6 receptors was assessed by bone marrow transplantation experiments and with a P2Y6 receptor antagonist.

RESULTS

NTPDase8 is the dominant enzyme responsible for the hydrolysis of nucleotides in the lumen of the colon. Compared with wild-type (WT) control mice, the colon of Entpd8-/- mice treated with DSS displayed significantly more histological damage, immune cell infiltration, apoptosis and increased expression of several proinflammatory cytokines. P2Y6 was the dominant P2Y receptor expressed at the mRNA level by the colonic epithelia. Irradiated P2ry6-/- mice transplanted with WT bone marrow were fully protected from DSS-induced intestinal inflammation. In agreement, the daily intrarectal injection of a P2Y6 antagonist protected mice from DSS-induced intestinal inflammation in a dose-dependent manner. Finally, human intestinal epithelial cells express NTPDase8 and P2Y6 similarly as in mice.

CONCLUSION

NTPDase8 protects the intestine from inflammation most probably by limiting the activation of P2Y6 receptors in colonic epithelial cells. This may provide a novel therapeutic strategy for the treatment of inflammatory bowel disease.

5-HT1A receptors mediate the analgesic effect of rosavin in a mouse model of oxaliplatin-induced peripheral neuropathic pain

Oxaliplatin, a third-generation platinum derivative, is the mainstay of current antineoplastic medications for advanced colorectal cancer therapy. However, peripheral neuropathic complications, especially cold allodynia, undermine the life-prolonging outcome of this anti-cancer agent. Rosavin, a phenylpropanoid derived originally from Rhodiola rosea, exhibits a wide range of therapeutic properties. The present study explored whether and how rosavin alleviates oxaliplatin-induced cold hypersensitivity in mice. In the acetone drop test, cold allodynia behavior was observed from days 3 to 5 after a single injection of oxaliplatin (6 mg/kg, i.p.). Cold allodynia was significantly attenuated following rosavin treatment (10 mg/kg, i.p.). Specific endogenous 5-HT depletion by three consecutive pretreatments with para-chlorophenylalanine (150 mg/kg/day, i.p.) abolished the analgesic action of rosavin; this effect was not observed following pretreatment with naloxone (opioid receptor antagonist, 10 mg/kg, i.p.). Furthermore, 5-HT_1A receptor antagonist WAY-100635 (0.16 mg/kg, i.p.), but not 5-HT₃ receptor antagonist MDL-72222 (1 mg/kg, i.p.), blocked rosavin-induced analgesia. These results suggest that rosavin may provide a novel approach to alleviate oxaliplatin-induced cold allodynia by recruiting the activity of 5-HT_1A receptors.

Soluble Fraction from Lysate of a High Concentration Multi-Strain Probiotic Formulation Inhibits TGF-β1-Induced Intestinal Fibrosis on CCD-18Co Cells

Fibrosis is a severe complication of chronic inflammatory disorders, such as inflammatory bowel disease (IBD). Current strategies are not fully effective in treating fibrosis; therefore, innovative anti-fibrotic approaches are urgently needed. TGF-β1 plays a central role in the fibrotic process by inducing myofibroblast differentiation and excessive extracellular matrix (ECM) protein deposition. Here, we explored the potential anti-fibrotic impact of two high concentration multi-strain probiotic formulations on TGF-β1-activated human intestinal colonic myofibroblast CCD-18Co. Human colonic fibroblast CCD-18Co cells were cultured in the presence of TGF-β1 to develop a fibrotic phenotype. Cell viability and growth were measured using the Trypan Blue dye exclusion test. The collagen-I, α-SMA, and pSmad2/3 expression levels were evaluated by Western blot analysis. Fibrosis markers were also analyzed by immunofluorescence and microscopy. The levels of TGF-β1 in the culture medium were assessed by ELISA. The effects of commercially available probiotic products VSL#3^® and Vivomixx^® were evaluated as the soluble fraction of bacterial lysates. The results suggested that the soluble fraction of Vivomixx^® formulation, but not VSL#3^®, was able to antagonize the pro-fibrotic effects of TGF-β1 on CCD-18Co cells, being able to prevent all of the cellular and molecular parameters that are related to the fibrotic phenotype. The mechanism underlying the observed effect appeared to be associated with inhibition of the TGF-β1/Smad signaling pathway. To our knowledge, this study provides the first experimental evidence that Vivomixx^® could be considered to be a promising candidate against intestinal fibrosis, being able to antagonize TGF-β1 pro-fibrotic effects. The differences that were observed in our fibrosis model between the two probiotics used could be attributable to the different number of strains in different proportions.

The Protective Effect of Rosavin from Rhodiola rosea on Radiation-Induced Intestinal Injury

Bioactive constituents from Rhodiola rosea L. (RRL) exhibit multiple pharmacological effects on diverse diseases. However, whether they are suitable for the treatment of radiation-induced intestinal injury (RIII) remains unclear. This study aims to investigate their roles and mechanisms in the RIII rat model. The radioprotective effects of the four bioactive constituents of RRL (salidroside, herbacetin, rosavin and arbutin) were evaluated by the cell viability of irradiated IEC-6 cells. Intestinal tissues were collected for histological analysis, localized inflammation and oxidative stress assessments. Our work showed that salidroside, rosavin and arbutin improved the cell viability of the irradiated IEC-6 cells, with the highest improvement in 12.5 μM rosavin group. The rosavin treatment significantly improved survival rate and intestinal damage in irradiated rats by modulating the inflammatory response and oxidative stress. Our work indicated that rosavin may be the optimal constituent of RRL for RIII treatment, providing an attractive candidate for radioprotection.

Resistant Maltodextrin Alleviates Dextran Sulfate Sodium-Induced Intestinal Inflammatory Injury by Increasing Butyric Acid to Inhibit Proinflammatory Cytokine Levels

Inflammatory bowel disease (IBD), one kind of intestinal chronic inflammatory disease, is characterized by colonic epithelial barrier injury, overproduction of proinflammatory cytokines, and fewer short-chain fatty acids (SCFAs). The present study is aimed at testing the hypothesis that resistant maltodextrin (RM), a soluble dietary fiber produced by starch debranching, alleviated dextran sulfate sodium- (DSS-) induced colitis in mice. Female C57BL/6 mice with or without oral administration of 50 mg/kg RM for 19 days were challenged with 3% DSS in drinking water to induce colitis (from day 14 to day 19). Although RM could not reverse DSS-induced weight loss or colon shortening, it reduced inflammatory cell infiltration and epithelial damage in colon tissue, as well as the transfer of intestinal permeability indicators including serum diamine oxidase (DAO) and D-lactic acid (D-LA). ELISA analysis indicated that RM significantly suppressed the increase of Th1 cytokines induced by DSS in the colon such as tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). The levels of proinflammatory cytokines interleukin-1β (IL-1β), IL-17, and IL-8 in the DSS group were significantly higher than those in the control group and RM group, but no significant difference was observed in the RM-DSS group compared with the RM group. Interestingly, IL-10 levels of the DSS group were significantly higher than those of the other groups. With respect to SCFAs, DSS administration significantly decreased the concentration of faecal butyric acid while the RM-DSS group showed a tendency to increase (P = 0.08). In general, RM alleviated dextran sulfate sodium-induced intestinal inflammation through increasing the level of butyric acid and subsequently inhibiting the expression of proinflammatory cytokines.

The Copper/Zinc Ratio Correlates With Markers of Disease Activity in Patients With Inflammatory Bowel Disease

BACKGROUND

Zinc (Zn) and copper (Cu) are trace elements that serve as cofactors in catalytic processes with impact on immune responses. In patients with inflammatory bowel disease (IBD), decreased levels of serum Zn and Cu have been observed. Here, we investigated the effect of inflammation on serum concentrations of these trace elements in patients with IBD.

METHODS

In this cross-sectional study, 98 patients with Crohn disease (CD) and 56 with ulcerative colitis (UC) were prospectively enrolled. Disease activity parameters, such as C-reactive protein (CRP) and fecal calprotectin (FC) were compared to serum Zn, Cu, and Cu/Zn ratio.

RESULTS

Zinc insufficiency was observed in 11.2% of patients with CD and 14.3% with UC, Cu insufficiency in 20.4% with CD and 7.1% with UC. Anemia, hypoalbuminemia, increased FC, and elevated CRP were more frequently present in Zn-insufficient patients with IBD. In contrast, lower serum CRP values and a trend to lower FC were observed in Cu-insufficient patients. In multiple linear regression models adjusted for age, gender, and serum albumin, CRP positively correlated with serum Cu (P < 0.001) and the Cu/Zn ratio in both CD and UC (P < 0.001) but not with serum Zn concentrations. FC levels correlated only with the Cu/Zn ratio in patients with UC (P < 0.038).

CONCLUSION

Systemic inflammation inversely affected the serum Zn and Cu concentrations and, consequently, resulted in an increased Cu/Zn ratio.

Porphyromonas gingivalis and Lactobacillus rhamnosus GG regulate the Th17/Treg balance in colitis via TLR4 and TLR2

OBJECTIVES

CD4⁺ T cells are the key to many immune-inflammatory diseases mediated by microbial disorders, especially inflammatory bowel disease (IBD). The purpose of this study was to explore how pathogenic and probiotic bacteria directly affect the T helper (Th)17 and T regulatory (Treg) cell balance among CD4⁺ T cells to regulate inflammation.

METHODS

Porphyromonas gingivalis (Pg; ATCC 33277) and Lactobacillus rhamnosus GG (LGG; CICC 6141) were selected as representative pathogenic and probiotic bacteria, respectively. Bacterial extracts were obtained via ultrasonication and ultracentrifugation. Flow cytometry, RT-qPCR, ELISAs, immunofluorescence and a Quantibody cytokine array were used. The dextran sodium sulphate (DSS)-induced colitis model was selected for verification.

RESULTS

The Pg ultrasonicate induced the apoptosis of CD4⁺ T cells and upregulated the expression of the Th17-associated transcription factor RoRγt and the production of the proinflammatory cytokines IL-17 and IL-6, but downregulated the expression of the essential Treg transcription factor Foxp3 and the production of the anti-inflammatory factors TGF-β and IL-10 via the TLR4 pathway. However, LGG extract maintained Th17/Treg homeostasis by decreasing the IL-17⁺ Th17 proportion and increasing the CD25⁺ Foxp3⁺ Treg proportion via the TLR2 pathway. In vivo, Pg-stimulated CD4⁺ T cells aggravated DSS-induced colitis by increasing the Th17/Treg ratio in the colon and lamina propria lymphocytes (LPLs), and Pg + LGG-stimulated CD4⁺ T cells relieved colitis by decreasing the Th17/Treg ratio via the JAK-STAT signalling pathway.

CONCLUSIONS

Our findings suggest that pathogenic Pg and probiotic LGG can directly regulate the Th17/Treg balance via different TLRs.

Probiotics of Diverse Origin and Their Therapeutic Applications: A Review

The increased awareness about the harmful effects of excessive use of antibiotics has created an interest in probiotics due to its beneficial effects on gut microbiota. These advantages of probiotics have attracted researchers to find out effects on human metabolism and their role in the treatment of diverse types of diseases or disorders. Additionally, they are clinically used as biocontrol agents in the treatment of mental disorders, anticancer agents and in decreasing the threat of necrotizing enterocolitis in premature infants. In this review, we have focused on various kinds of probiotics and various nondairy substrates for their production. We have also included the importance of probiotics in the treatment of metabolic disorders, type II diabetes and infectious diseases. Furthermore, this review emphasizes applications of probiotics originated from different organisms. Their future health perspectives are discussed to gain insight into their applications.KEY TEACHING POINTSThe global market of probiotics is enormously rising day by day due to its highly beneficial effect on human microbiota.Additionally, these are used as biocontrol agents; mental disorders prevent cancer and decrease the threat of necrotizing enterocolitis (NEC) in premature infants.This review focuses on various kinds of sources of probiotics and various non-dairy substrates for the production of probiotics.The importance of probiotics in the treatment of metabolic disorders, type II diabetes control, cancer and treatment of infectious diseases are also described.It emphasizes diversified probiotics and their applications in various human health aspects and future perspectives.

Bacillus licheniformis Zhengchangsheng® attenuates DSS-induced colitis and modulates the gut microbiota in mice

Human inflammatory bowel disease (IBD) and experimental colitis models in mice are associated with shifts in gut microbiota composition, and several probiotics are widely used to improve gastrointestinal health. Here, we investigated whether the probiotic Bacillus licheniformis Zhengchangsheng® (BL) ameliorates dextran sulphate sodium (DSS)-induced colitis through alteration of the gut microbiota. Experimental colitis was induced in BALB/C mice by dissolving 3% DSS in their drinking water for 7 days, which were gavaged with 0.2 ml phosphate-buffered saline or BL (3×107 cfu/ml) once a day. Administration of BL attenuated several effects of DSS-induced colitis, including weight loss, increased disease activity index, and disrupted intestinal barrier integrity. In addition, BL mitigated the reduction in faecal microbiota richness in DSS treated mice. Interestingly, BL was found to reduce the elevated circulating endotoxin level in mice with colitis by modulating the microbial composition of the microbiota, and this was highly associated with a proportional decrease in gut Bacteroidetes. Our results demonstrate that BL can attenuate DSS-induced colitis and provide valuable insight into microbiota interactions during IBD.

Reappraisal of antibodies against Saccharomyces cerevisiae (ASCA) as persistent biomarkers in quiescent Crohn's disease

A clear correlation exists between microbiota and the dysregulation of the immune response in Inflammatory Bowel Diseases (IBD), which comprise Crohn's disease (CD) and ulcerative colitis (UC). These unbalanced reactions also involve humoral responses, with antibodies against Saccharomyces cerevisiae. Thus, here we aimed to quantify IgA and IgG specific to S. cerevisiae (ASCA) in quiescent CD and UC, to correlate the production of these antibodies with patient's inflammatory response and disease clinical presentation. Twenty-nine subjects (16 CD and 13 UC) and 45 healthy controls were enrolled in this study and had plasma samples tested for ASCA and cytokines (IL-2, IL-4, IL-6, IL-10, IFN-γ, TNF-α), besides clinical evaluation. IBD patients had increase IgA and IgG ASCA, especially those with colonic (L2) and fistulizing (B3) CD. Similarly, patients who dropped out the treatment had augmented ASCA, while IgG was reduced in those receiving sulfasalazine treatment. Furthermore, the quiescent CD patients had elevated IL-6 on plasma, especially in the absence of treatment, together with increased counter regulatory response of IL-10. There was a positive correlation between IgA and IgG on CD but not UC, as well as between IgA and TNF in total IBD patients. In addition, the levels of IgG x TNF, IgA x IL-10 and IgG x IL-10 were also correlated in CD, indicating that ASCA production may be influenced by the inflammatory response. Finally, we concluded that ASCA could be pointed as relevant biomarker of CD presentation and residual inflammation, even in clinical remission patients.

Contribution of Zinc and Zinc Transporters in the Pathogenesis of Inflammatory Bowel Diseases

Intestinal epithelial cells cover the surface of the intestinal tract. The cells are important for preserving the integrity of the mucosal barriers to protect the host from luminal antigens and pathogens. The mucosal barriers are maintained by the continuous and rapid self-renewal of intestinal epithelial cells. Defects in the self-renewal of these cells are associated with gastrointestinal diseases, including inflammatory bowel diseases and diarrhea. Zinc is an essential trace element for living organisms, and zinc deficiency is closely linked to the impaired mucosal integrity. Recent evidence has shown that zinc transporters contribute to the barrier function of intestinal epithelial cells. In this review, we describe the recent advances in understanding the role of zinc and zinc transporters in the barrier function and homeostasis of intestinal epithelial cells.

An agonist of a zinc-sensing receptor GPR39 enhances tight junction assembly in intestinal epithelial cells via an AMPK-dependent mechanism

Intestinal barrier function depends on integrity of tight junctions, which serve as barriers to transepithelial influx of noxious substances/microorganisms from gut lumen. The G-protein coupled receptor 39 (GPR39) is a zinc-sensing receptor, which is expressed in several cell types including intestinal epithelial cells (IECs). The main objective of this study was to investigate the effect of GPR39 activation on tight junction assembly in IECs. Treatment with TC-G 1008 (1 μM -10 μM), a GPR39 agonist, and zinc (10 μM -100 μM) increased tight junction assembly in T84 cells. This effect was suppressed by pretreatment with compound C, an inhibitor of AMP-activated protein kinase (AMPK). In addition, western blot analysis revealed that treatment with TC-G 1008 induced AMPK activation in time- and concentration-dependent manners. Interestingly, inhibitors of phospholipase C (PLC) and calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ) abrogated the effect of TC-G 1008 on inducing AMPK activation, tight junction assembly and zonula occludens-1 re-organization. Collectively, this study reveals a novel role of GPR39 in enhancing tight junction assembly in IECs via PLC-CaMKKβ-AMPK pathways. GPR39 agonists may be beneficial in the treatment of diseases associated impaired intestinal barrier function.

Update on the Gastrointestinal Microbiome in Systemic Sclerosis

PURPOSE OF REVIEW

Accumulating evidence suggests that gut microbiota affect the development and function of the immune system and may play a role in the pathogenesis of autoimmune diseases. The purpose of this review is to summarize recent studies reporting gastrointestinal microbiota aberrations associated with the systemic sclerosis disease state.

RECENT FINDINGS

The studies described herein have identified common changes in gut microbial composition. Specifically, patients with SSc have decreased abundance of beneficial commensal genera (e.g., Faecalibacterium, Clostridium, and Bacteroides) and increased abundance of pathobiont genera (e.g., Fusobacterium, Prevotella, Erwinia). In addition, some studies have linked specific genera with the severity of gastrointestinal symptoms in systemic sclerosis. More research is needed to further characterize the gastrointestinal microbiota in systemic sclerosis and understand how microbiota perturbations can affect inflammation, fibrosis, and clinical outcomes. Interventional studies aimed at addressing/correcting these perturbations, either through dietary modification, pro/pre-biotic supplementation, or fecal transplantation, may lead to improved outcomes for patients with systemic sclerosis.