Involvement of Proinflammatory Arachidonic Acid (ARA) Derivatives in Crohn’s Disease (CD) and Ulcerative Colitis (UC)

Integrating 16 S rRNA gene sequencing and metabolomics analysis to reveal the mechanism of Angelica sinensis oil in alleviating ulcerative colitis in mice

Angelica sinensis (Oliv.) Diels (AS) is a commonly used herbal medicine and culinary spice known for its gastrointestinal protective properties. Angelica sinensis oil (AO) is the main bioactive component of AS. However, the therapeutic effects and mechanisms of AO on the gastrointestinal tract remain unclear. In this study, we aim to investigated the potential of AO in restoring gut microbiota disorder and metabolic disruptions associated with ulcerative colitis (UC). A systematic chemical characterization of AO was conducted using GC×GC-Q TOF-MS. A UC mouse model was established by freely drinking DSS to assess the efficacy of AO. Utilizing 16 S rRNA sequencing in combination with untargeted metabolomics analysis of serum, we identified alterations in gut microbiota, differential metabolites, and pathways influenced by AO in UC treatment, thereby elucidating the therapeutic mechanism of AO in UC management. Pharmacodynamic results indicated that AO effectively inhibited the content of inflammation mediators, such as Interleukin-1β, Interleukin-6 and tumor necrosis factor-α, and proserved colon tissue integrity in UC mice. Furthermore, AO significantly downregulated the abundance of pathogenic bacteria (Bacteroidetes, Proteobacteria, and Desulfobacteriaceae) while increasing the abundance of beneficial bacteria (Firmicutes, Blautia, Akkermansia, and Lachnospiraceae). Metabolomics analysis highlighted significant disruptions in endogenous metabolism in UC mice, with a notable restoration of SphK1 and S1P levels following AO administration. Besides, we discovered that AO regulated the balance of sphingolipid metabolism and protected the intestinal barrier, potentially through the SphK1/MAPK signaling pathway. Overall, this study indicated that AO effectively ameliorates the clinical manifestations of UC by synergistically regulating gut microbe and metabolite homeostasis. AO emerges as a potential functional and therapeutic ingredient for UC treatment.

Flavonoids-Enriched Vegetal Extract Prevents the Activation of NFκB Downstream Mechanisms in a Bowel Disease In Vitro Model

Inflammatory bowel disease (IBD) incidence has increased in the last decades due to changes in dietary habits. IBDs are characterized by intestinal epithelial barrier disruption, increased inflammatory mediator production and excessive tissue injury. Since the current treatments are not sufficient to achieve and maintain remission, complementary and alternative medicine (CAM) becomes a primary practice as a co-adjuvant for the therapy. Thus, the intake of functional food enriched in vegetal extracts represents a promising nutritional strategy. This study evaluates the anti-inflammatory effects of artichoke, caihua and fenugreek vegetal extract original blend (ACFB) in an in vitro model of gut barrier mimicking the early acute phases of the disease. Caco2 cells cultured on transwell supports were treated with digested ACFB before exposure to pro-inflammatory cytokines. The pre-treatment counteracts the increase in barrier permeability induced by the inflammatory stimulus, as demonstrated by the evaluation of TEER and CLDN-2 parameters. In parallel, ACFB reduces p65NF-κB pro-inflammatory pathway activation that results in the decrement of COX-2 expression as PGE2 and IL-8 secretion. ACFB properties might be due to the synergistic effects of different flavonoids, indicating it as a valid candidate for new formulation in the prevention/mitigation of non-communicable diseases.

6-Gingerol ameliorates ulcerative colitis by inhibiting ferroptosis based on the integrative analysis of plasma metabolomics and network pharmacology

6-Gingerol (6-G), an active ingredient of ginger with anti-inflammation and anti-oxidation properties, can treat ulcerative colitis (UC). However, its underlying mechanism is still unclear. In this study, the pharmacodynamic evaluation of 6-G for treating UC was performed, and the mechanism of 6-G in ameliorating UC was excavated by plasma metabolomics and network pharmacology analysis, which was further validated by experimental and molecular docking. The results showed that 6-G could notably reduce diarrhea, weight loss, colonic pathological damage, and inflammation in UC mice. Plasma metabolomic results indicated that 6-G could regulate 19 differential metabolites, and its metabolic pathways mainly involved linoleic acid metabolism and arachidonic acid metabolism, which were closely associated with ferroptosis. Moreover, 60 potential targets for 6-G intervention on ferroptosis in UC were identified by network pharmacology, and enrichment analysis revealed that 6-G suppressed ferroptosis by modulating lipid peroxidation. Besides, the integration of metabolomics and network pharmacology showed that the regulation of 6-G on ferroptosis focused on 3 key targets, including ALOX5, ALOX15, and PTGS2. Further investigation indicated that 6-G significantly inhibited ferroptosis by decreasing iron load and malondialdehyde (MDA), and enhanced antioxidant capacity by reducing the content of glutathione disulfide (GSSG) and increasing the levels of superoxide dismutase (SOD) and glutathione (GSH) in UC mice and RSL3-induced Caco-2 cells. Furthermore, molecular docking showed the high affinity of 6-G with the identified 3 key targets. Collectively, this study elucidated the potential of 6-G in ameliorating UC by inhibiting ferroptosis. The integrated strategy also provided a theoretical basis for 6-G in treating UC.

The histamine H4 receptor antagonist 1-[(5-chloro-2,3-dihydro-1-benzofuran-2-yl)methyl]-4-methyl-piperazine(LINS01007) prevents the development of DSS-induced colitis in mice

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with growing incidence worldwide. Our group reported the compound 5-choro-1-[(2,3-dihydro-1-benzofuran-2-yl)methyl]piperazine (LINS01007) as H4R antagonist (pKi 6.2) and therefore the effects and pharmacological efficacy on a DSS-induced mice model of UC were assessed in this work. Experimental acute colitis was induced in male BALB/c mice (n = 5-10) by administering 3 % DSS in the drinking water for six days. The test compound LINS01007 was administered daily i.p. (5 mg/kg) and compared to control group without treatment. Body weight, water and food consumption, and the presence of fecal blood were monitored during 7-day treatment period. The levels of inflammatory markers (PGE2, COX-2, IL-6, NF-κB and STAT3) were also analyzed. Animals subjected to the acute colitis protocol showed a reduction in water and food intake from the fourth day (p < 0.05) and these events were prevented by LINS01007. Histological signs of edema, hyperplasia and disorganized intestinal crypts, as well as neutrophilic infiltrations, were found in control mice while these findings were significantly reduced in animals treated with LINS01007. Significant reductions in the levels of PGE2, COX-2, IL-6, NF-κB and STAT3 were observed in the serum and tissue of treated animals. The results demonstrated the significant effects of LINS01007 against DSS-induced colitis, highlighting the potential of H4R antagonism as promising treatment for this condition.

Abnormal expression of oxylipins and related synthesizing/signaling pathways in inflammatory bowel diseases

We investigated selected oxylipins and related synthesizing/signaling pathways in 28 patients with Crohn's disease (CD), 19 patients with ulcerative colitis (UC), and 39 controls. Plasma and mucosal PUFA/oxylipin profiles were analyzed by LC-MS/MS. mRNA expression of 5, 12 and 15-lipooxygenases, FPR2/ALXR, FFAR4/GPR120, annexin A1, and interleukin-10 were analyzed by qRT-PCR. Oxylipin profile and related metabolic pathways were altered in both CD and UC patients. The patterns were characterized by increased prostaglandins, leukotrienes, and lipoxins and overexpression of 5-lipoxygenase, FPR2/ALXR, annexin A1, and interleukin-10 genes, but decreased n-3 PUFAs and 18-hydroxyeisapentaenoic acid. The gene of 15-lipoxygenase was under-expressed mainly in UC patients. CD and UC are associated with unbalanced n-6 ​​and n-3 derivatives and pro-inflammatory and anti-inflammatory/pro-resolving mediators favoring the former compounds. The findings suggest that oxylipins engage in the pathophysiology of the diseases. Targeting oxylipin's metabolic pathways would be a promising therapy for inflammatory bowel diseases.

Genomic analysis in the colon tissues of omega-3 fatty acid-treated rats identifies novel gene signatures implicated in ulcerative colitis

Several long-term intervention trials only studied the ex vivo immunological function to elucidate the beneficial mechanisms of n-3 polyunsaturated fatty acids (PUFA) in the ulcerative colitis (UC). An unbiased whole-transcriptome analysis would be more valuable to obtain a comprehensive understanding of the processes and genes regulated by n-3 PUFA in vivo. In this study, we have performed microarray analysis in the colon tissues of dextran sulfate sodium (DSS)-induced UC in rats supplemented with n-6 PUFA, n-3PUFA and long-chain n-3PUFA (LC-n3PUFA). We have identified the novel gene signatures previously not linked to colitis such as Etv3, Clec4d, CD180, CD72, Megf11, and Angptl4 which are most downregulated in both n-3PUFA and LC-n3PUFA groups compared to the n-6PUFA group. The most upregulated genes were Nr1i3, Nptx2, and Zfp810 in both n-3PUFA and LC-n3PUFA groups. The RT-PCR analysis confirmed similar results. Interestingly, LPS treatment in macrophages upregulated the Megf11, Etv3, CD180, and Angptl4, and correlated with increased secretion of cytokines. Gene silencing of Etv3, Megf11, and CD180 in rats using intravascular delivery of siRNA-lipoparticles attenuated the DSS-induced ulceration and mucosal damage. Thus, our genome-wide microarray analysis identified novel genes regulated by omega-3 PUFA and offers new drug targets that could prevent or reduce UC.

Berberine regulates intestinal microbiome and metabolism homeostasis to treat ulcerative colitis

AIMS

This study aims to investigate the effects of berberine (BBR) on the intestinal microbiome (IM) and serum metabolome in ulcerative colitis (UC). Furthermore, the underlying molecular mechanisms of BBR in treating UC also will be explored systematically.

MATERIALS AND METHODS

A multi-omics approach that integrates the 16s rDNA, serum metabolome, transcriptomics and bioinformatics was profiled to investigate the potential effects of BBR on the IM, serum metabolites and metabolic pathways, and gene expression. In addition, BBR-induced fecal microbiota transplantation (BBR_FMT) was conducted in pseudo germ-free mice combined with the UC model to explore the effects of the IM on metabolic pathways and gene expression. The results of the transcriptomics and metabolic pathway-related genes were further examined by real-time PCR and western blot.

KEY FINDINGS

BBR ameliorated the community of IM and significantly promoted the abundance of f__Muribaculaceae, Bacteroides, Dubosiella, Allobaculum and Akkermansia. The metabolic profiles in UC mice were significantly modulated by BBR treatment. Furthermore, the inflammation-related metabolites and metabolic pathways in serum were negatively correlated with the abundance of Bacteroides and Akkermansia, which were induced by BBR treatment. BBR_FMT significantly inhibited the arachidonic acid (AA) metabolism pathway and its multiple markers with the mediation of the IM.

SIGNIFICANCE

BBR ameliorated serum metabolic homeostasis by regulating the IM. The inhibition of the AA metabolism pathway and its multiple markers was one of the mechanisms of BBR in the treatment of UC.

Integration of gut microbiome and serum metabolome revealed the effect of Qing-Wei-Zhi-Tong Micro-pills on gastric ulcer in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Qing-Wei-Zhi-Tong Micro-pills (QWZT) is herbal compound used in the treatment of GU, whose functions include clearing the stomach and fire, softening the liver and relieving pain. However, its mechanistic profile on host intestinal microbiota and metabolism has not been determined.

AIM OF THE STUDY

The present study aimed to observe the healing effect of QWZT on acetic acid-induced gastric ulcer in a rat model and to preliminarily elucidate its possible therapeutic mechanism from the perspective of host intestinal microbiota and metabolism.

MATERIALS AND METHODS

The Wistar male rats (7 weeks old; weight 180-200 g) were randomly divided into normal control group (NC), acetic acid-induced gastric ulcer group (GU), and QWZT treatment group (High dose: 1250 mg/kg/day, Middle dose: 625 mg/kg/day, Low dose: 312.5 mg/kg/day) of 6 rats each. An acetic acid-induced gastric ulcer rat model was constructed based on anatomical surgery. QWZT (High dose, Middle dose, and Low dose) was used to treat gastric ulcer rats for 7 days by gavage. At the end of treatment, the body weight, macroscopic condition of gastric tissue ulcers, pathological changes (HE staining), inflammatory factors, oxidative stress factors, and endocrine factors were assessed in each group of rats. Fresh feces and serum from each group of rats were collected for microbiome and metabolome analysis on the machine, respectively. Drug-disease common targets and functional pathways were captured based on network pharmacology. The complex network of Herbs-Targets-Pathways-Metabolites-Microbiota interactions was constructed. Ultimately, Fecal Microbiota Transplantation (FMT) evaluated the contribution of gut microbiota in disease.

RESULTS

QWZT increased the abundance of beneficial bacteria (Bacteroides, Alloprevotella, Rikenellaceae_RC9_gut_group, Lactobacillus, Lachnospiraceae_NK4A136_group, Parabacteroides, etc.), reduced the abundance of harmful bacteria (Micromonospora, Geobacter, Nocardioides, and Arenimonas, etc.), reduced the levels of inflammatory mediators (12,13-EpOME, 9,10-Epoxyoctadecenoic acid, SM(d18:1/16:0) and Leukotriene A4, etc.), restored host metabolic disorders (Linoleic acid metabolism, Glycerophospholipid metabolism, and Arachidonic acid metabolism), and regulated the level of cytokines (IL-6, TNF-a, SOD, MDA, PEG-2 and NO), ultimately exerting an anti-ulcer effect. Apart from that, FMT improved acetic acid-induced gastric ulcers in rats.

CONCLUSION

QWZT improved acetic acid-induced gastric ulcers in rats by remodeling intestinal microbiota and regulating host metabolism. This work may promote the process of developing and utilizing clinical applications of QWZT.

Calprotectin Is Associated with HETE and HODE Acids in Inflammatory Bowel Diseases

BACKGROUND

Intestinal diseases are identified as autoimmune phenomena attributed to a specific virus that binds to the mucosal epithelium. The importance of precise diagnostic processes and identification is emphasized, but the multifaceted and complex etiological factors pose challenges for effective treatment. A recent supplementary study suggested a linkage between the secretion of calprotectin, a protein associated with inflammatory processes, and increased levels of hydroxyeicosatrienoic acids (HETE) and hydroxyoctadecadienoic (HODE) compounds.

METHODS

Sixty-two patients (average age: 14.06 ± 2.93 years) suffering from inflammatory bowel diseases were included in this study. Comparative analyses were performed to assess the concentrations of calprotectin against the levels of arachidonic acid derivatives. The calprotectin concentration was determined using the enzyme-linked immunosorbent assay (ELISA) method. The derivatives of HETE and HODE were identified through liquid chromatography.

RESULTS

Patients with Crohn's disease (CD) displayed higher average concentrations of fatty acid metabolites; however, no correlation with calprotectin was observed. A dependency of 12S HETE concentration relative to age was noted in the CD group, and a similar trend was also identified in ulcerative colitis (UC), with the significant metabolites being 15 HETE and 5 oxoETE. In UC patients, a positive correlation was established between the calprotectin concentration and the acids 5-HETE and 12-HETE.

CONCLUSIONS

These findings may be instrumental for monitoring the inflammatory states of patients and indicating a pathway for intervention. The metabolite 16RS HETE is associated with UC activity, and 15-HETE is related to the disease's duration. A relatively more significant role of HETE acids in the progression of the disease was observed in UC.

Fatty acids and lipid mediators in inflammatory bowel disease: from mechanism to treatment

Inflammatory Bowel Disease (IBD) is a chronic, relapsing inflammatory disorder of the gastrointestinal tract. Though the pathogenesis of IBD remains unclear, diet is increasingly recognized as a pivotal factor influencing its onset and progression. Fatty acids, essential components of dietary lipids, play diverse roles in IBD, ranging from anti-inflammatory and immune-regulatory functions to gut-microbiota modulation and barrier maintenance. Short-chain fatty acids (SCFAs), products of indigestible dietary fiber fermentation by gut microbiota, have strong anti-inflammatory properties and are seen as key protective factors against IBD. Among long-chain fatty acids, saturated fatty acids, trans fatty acids, and ω-6 polyunsaturated fatty acids exhibit pro-inflammatory effects, while oleic acid and ω-3 polyunsaturated fatty acids display anti-inflammatory actions. Lipid mediators derived from polyunsaturated fatty acids serve as bioactive molecules, influencing immune cell functions and offering both pro-inflammatory and anti-inflammatory benefits. Recent research has also highlighted the potential of medium- and very long-chain fatty acids in modulating inflammation, mucosal barriers, and gut microbiota in IBD. Given these insights, dietary intervention and supplementation with short-chain fatty acids are emerging as potential therapeutic strategies for IBD. This review elucidates the impact of various fatty acids and lipid mediators on IBD and delves into potential therapeutic avenues stemming from these compounds.

Set up and validation of a sensitive method to quantify prostaglandins, prostaglandin-glycerol esters and prostaglandin-ethanolamides, as well as their respective precursors

Arachidonic acid-derived prostaglandins are widely studied for their role in inflammation. However, besides arachidonic acid, other arachidonic moiety-containing lipids can be metabolized by COX-2. Indeed, the endocannabinoids 2-arachidonoylglycerol (2-AG) and N-arachidonoylethanolamine (anandamide, AEA) can follow the same biochemical pathways than arachidonic acid leading to the formation of prostaglandin-glycerol esters (PG-G) and prostaglandin-ethanolamides (or prostamides, PG-EA), respectively. The data reported so far support the interest of these bioactive lipids in inflammatory conditions. However, there is only a handful of methods described for their quantification in biological matrices. Moreover, given the shared biochemical pathways for arachidonic acid, 2-AG and AEA, a method allowing for the quantification of these precursors and the corresponding prostaglandin derivatives appears as largely needed. Thus, we report here the development and validation of a single run UPLC-MS/MS quantification method allowing the quantification of these endocannabinoids-derived mediators together with the classical prostaglandin. Moreover, we applied the method to the quantification of these lipids in vitro (using lipopolysaccharides-activated J774 macrophage cells) and in vivo in several tissues from DSS-induced colitis mice. This femtomole-range method should improve the understanding of the interaction between these lipid mediators and inflammation.

Altered mucosal and plasma polyunsaturated fatty acids, oxylipins, and endocannabinoids profiles in Crohn's disease

Selected mucosal and plasma polyunsaturated fatty acids (PUFAs) and related oxylipins and endocannabinoids were determined in 28 Crohn's disease (CD) patients and 39 controls. Fasting blood and colonic biopsies were collected in all participants, during a disease flare for the patients. Thirty-two lipid mediators including PUFAs, oxylipins, and endocannabinoids were assessed by LC-MS/MS. The pattern of lipid mediators in CD patients is characterized by an increase in arachidonic acid-derived oxylipins and endocannabinoids and a decrease in n-3 PUFAs and related endocannabinoids. A model combining increased 6-epi-lipoxin A4 and 2-arachidonyl glycerol with decreased docoasapentaenoic acid in plasma fairly discriminates patients from controls and may represent a lipidomic signature for CD flare. The study findings suggest that lipid mediators are involved in CD pathophysiology and may serve as biomarkers for disease flare. Further research is required to confirm the role of these bioactive lipids and test their therapeutic potential in CD.

Metabolomic profiling implicates mitochondrial and immune dysfunction in disease syndromes of the critically endangered black rhinoceros (Diceros bicornis)

The critically endangered black rhinoceros (Diceros bicornis; black rhino) experiences extinction threats from poaching in-situ. The ex-situ population, which serves as a genetic reservoir against impending extinction threats, experiences its own threats to survival related to several disease syndromes not typically observed among their wild counterparts. We performed an untargeted metabolomic analysis of serum from 30 ex-situ housed black rhinos (Eastern black rhino, EBR, n = 14 animals; Southern black rhino, SBR, n = 16 animals) and analyzed differences in metabolite profiles between subspecies, sex, and health status (healthy n = 13 vs. diseased n = 14). Of the 636 metabolites detected, several were differentially (fold change > 1.5; p < 0.05) expressed between EBR vs. SBR (40 metabolites), female vs. male (36 metabolites), and healthy vs. diseased (22 metabolites). Results suggest dysregulation of propanoate, amino acid metabolism, and bile acid biosynthesis in the subspecies and sex comparisons. Assessment of healthy versus diseased rhinos indicates involvement of arachidonic acid metabolism, bile acid biosynthesis, and the pentose phosphate pathway in animals exhibiting inflammatory disease syndromes. This study represents the first systematic characterization of the circulating serum metabolome in the black rhinoceros. Findings further implicate mitochondrial and immune dysfunction as key contributors for the diverse disease syndromes reported in ex-situ managed black rhinos.

Current and emerging biomarkers for ulcerative colitis

INTRODUCTION

Ulcerative colitis (UC) is a chronic illness requiring lifelong management that could be enhanced by personalizing care using biomarkers.

AREAS COVERED

The main biomarker discovery modalities are reviewed, highlighting recent results across the spectrum of applications, including diagnostics (serum anti-αvβ6 antibodies achieving an area under the curve [AUC] = 0.99; serum oncostatin M AUC = 0.94), disease activity assessment (fecal calprotectin and serum trefoil factor 3: AUC > 0.90), prognostication of the need for treatment escalation (whole blood transcriptomic panels and CLEC5A/CDH2 ratio: AUC > 0.90), prediction of treatment response, and early identification of patients with subclinical disease. The use of established biomarkers is discussed, along with new evidence regarding autoantibodies, proteins, proteomic panels, transcriptomic signatures, deoxyribonucleic acid methylation patterns, and UC-specific glycomic and metabolic disturbances.

EXPERT OPINION

Novel biomarkers will pave the way for optimized UC care. However, validation, simplification, and direct clinical translation of complex models may prove challenging. Currently, few candidates exist to assess key characteristics, such as UC susceptibility, histological disease activity, drug response, and long-term disease behavior. Further research will likely not only reveal new tools to tackle these issues but also contribute to understanding UC pathogenesis mechanisms.