Goat whey ameliorates intestinal inflammation on acetic acid-induced colitis in rats

Whey Protein Hydrolysate Exerts Anti-Inflammatory Effects to Alleviate Dextran Sodium Sulfate (DSS)-Induced Colitis via Microbiome Restoration

Whey protein hydrolysate (WPH) has been shown to have a variety of bioactivities. This study aimed to investigate the preventive effect of WPH on dextran sodium sulfate (DSS)-induced colitis in C57BL/6J mice. The results indicated that WPH intervention for 37 days was effective in delaying the development of colonic inflammation, and high doses of WPH significantly inhibited weight loss (9.16%, n = 8, p < 0.05), protected the colonic mucosal layer, and significantly reduced the levels of inflammatory factors TNF-α, IL-6, and IL-1β in mice with colitis (n = 8, p < 0.05). In addition, WPH intervention was able to up-regulate the short-chain fatty acids secretion and restore the gut microbiome imbalance in mice with colitis. Notably, high-dose WPH intervention increased the relative abundance of norank_f_Muribaculaceae by 1.52-fold and decreased the relative abundance of Romboutsia and Enterobacter by 3.77-fold and 2.45-fold, respectively, compared with the Model group. WPH intervention protected colitis mice mainly by reversing the microbiome imbalance and regulating the major histocompatibility complex (MHC) class I pathway. This study showed that WPH has anti-inflammatory activity and a promising colitis management future.

Vagus Nerve Stimulation Relives Irritable Bowel Syndrome and the Associated Depression via α7nAChR-mediated Anti-inflammatory Pathway

OBJECTIVES

The present study is designed to investigate the role of vagus nerve in the treatments of irritable bowel syndrome (IBS) and the associated central nervous system disorders.

METHODS

An IBS animal model was established by giving acetic acid and chronic-acute stress (AA-CAS) treatment in adult male Wistar rats. Subdiaphragmatic vagotomy (SDV) and vagus nerve stimulation (VNS) were performed to intervene the excitability of vagus nerve. Permeability of blood brain barrier (BBB) was measured and agonist and antagonist of α7 nicotinic acetylcholine receptor (α7nAChR) were used to explore the relevant mechanisms.

RESULTS

AA-CAS treatment resulted in abnormal fecal output, increased visceral sensitivity, depressive-like behaviors, and overexpression of inflammatory mediators, all of which were reversed by VNS treatment. The effects of VNS could also be observed when α7nAChR agonist was applied. Whereas α7nAChR antagonist (methyllycaconitine, MLA) reversed VNS's effects. Interestingly, VNS also reduced the increased permeability of blood brain barrier (BBB) following AA-CAS treatment in IBS rats. SDV treatment only show temporary efficacy on AA-CAS-induced symptoms and had no effect on the permeability of BBB.

CONCLUSION

The intestinal abnormalities and depressive symptoms in IBS rats can be improved by VNS treatment. This positive effect of VNS was achieved through α7nAChR-mediated inflammatory pathway and may also be associated with the decreased of BBB permeability.

Mix of almond baru (Dipteryx alata Vog.) and goat whey modulated intestinal microbiota, improved memory and induced anxiolytic like behavior in aged rats

The objective was to evaluate the effects of the consumption of a mix of baru almond and goat whey on memory performance and anxiety parameters related to the intestinal health of rats treated during aging. The animals were divided into three groups and treated by gavage for 10 weeks (n = 10/each group): Control (CT) - distilled water; Baru almond (BA) - 2000 mg of baru/kg of body weight; and Baru + Whey (BW) - 2000 mg of baru + 2000 mg of goat milk whey/kg of body weight. Anxiety behavior, memory, brain fatty acid profile and fecal microbiota were measured. BA and BW realized less grooming, spent more time in the central area of the open field and the open arms, and realized more head dipping in the elevated plus maze. A higher rate of exploration of the new object in the short and long-term memory was observed in BA and BW. There was an increase in the deposition of MUFAs and PUFAs and oleic acid in the brain of BA and BW. Regarding spatial memory, BA and BW performed better, with an emphasis on BW. There was a beneficial modulation of the fecal microbiota with a reduction of the pathogenic genus Clostridia_UFC-014 in BA and BW and an increase in the abundance of metabolic pathways of interest in the brain-gut axis. Thus, consumption of the mix is efficient in beneficially altering the intestinal microbiota, improving memory and anxiolytic-like behavior in rats during aging.

Rupatadine ameliorated ulcerative colitis in rats via modulation of platelet-activatiweng factor/interleukin-6/vascular endothelial growth factor signalling pathway

OBJECTIVES

This study aimed to analyse the potential effect of rupatadine (RUP) on ulcerative colitis (UC) induced by acetic acid (AA).

METHODS

Forty male adult Wistar rats were divided into five groups: Control group: received vehicles for 14 days; AA model group: received AA at the 13th day; Sulfasalazine (SLZ) + AA group: received SLZ (250 mg/kg) for 14 days and AA at the 13th day; RUP-3 + AA group: received RUP (3 mg/kg/day) for 14 days and AA at the 13th day; and RUP-6 + AA group: received RUP (6 mg/kg/day) for 14 days and AA at the 13th day. Evidence of UC was assessed both macroscopically and microscopically. Oxidative stress markers (total antioxidant capacity and malondialdehyde), antioxidant enzyme (superoxide dismutase), histamine and platelet-activating factor (PAF) were determined. Immunohistochemical estimations of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) were done.

KEY FINDINGS

The AA group showed evidence of UC that was associated with a significant increase in oxidative stress, histamine and PAF levels with significant elevation in colonic VEGF and IL-6 immuno-expressions. RUP, in a dose-dependent manner, significantly ameliorated UC.

CONCLUSION

RUP protects against UC by reducing oxidative stress and by regulating the PAF/IL-6/VEGF pathway.

Progress in understanding of relationship between short chain fatty acids and irritable bowel syndrome

Irritable bowel syndrome (IBS) is a functional intestinal disease whose pathogenesis has not yet been fully defined. The main clinical manifestations of IBS are irregular abdominal pain, abdominal distension, and changes in stool character and defecation habits. As one of the pathogeneses of IBS, intestinal flora imbalance plays an important role in the development of IBS. The vast majorities of short chain fatty acids (SCFAs) are produced through the interaction of intestinal flora with host diet in the colon. As one of the main metabolites of intestinal flora, SCFAs have the effects of intestinal barrier protection, immune regulation, anti-inflammation, and regulation of visceral sensitivity in the intestine. In recent years, with the increasing attention to SCFAs, studies on the relationship between SCFAs and IBS are emerging. This review summarizes the progress in the understanding of the relationship between SCFAs and IBS in recent five years.

Protective effect of mirtazapine against acetic acid-induced ulcerative colitis in rats: Role of NLRP3 inflammasome pathway

AIMS

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that causes long-lasting inflammation on the innermost lining of the colon and rectum. Mirtazapine (MRT) is a well-known antidepressant that was proven to have anti-inflammatory activity; however, to date, its role has not been investigated in UC. The current study aimed to investigate the role and mechanism of MRT in UC.

MAIN METHOD

Acetic acid (AA) was used for UC induction, and sulfasalazine (SLZ) was used as a positive control. Rats were divided into five equal groups; as follows; normal control, AA, SLZ (received SLZ in a dose of 250 mg/kg for 14 days), MRT10 (received MRT in a dose of 10 mg/kg/day for 14 days), and MRT30 (received MRT in a dose of 30 mg/kg/day for 14 days) groups. Macroscopic and microscopic examinations together with oxidative stress parameters evaluation were done. NOD-like receptors-3 (NLRP3), caspase-1, TNF-α, and nuclear factor kappa B (NF-κB) expression together with interleukin (IL)-1β and IL-18 levels were examined.

KEY FINDING

MRT, in a dose-dependent manner, prevented the macroscopic and microscopic colonic damage and corrected the oxidative stress induced by AA. Moreover, MRT decreased the colonic tissue NLRP3 inflammasome, caspase-1, NF-κB, TNF-α expressions, IL-1β, and IL-18 levels that were elevated in colonic tissue by the AA.

SIGNIFICANCE

MRT has a dose-dependent protective effect against UC that was mediated mainly by its anti-inflammatory activity with modulation of NLRP3/caspase-1 inflammatory pathway.

Evaluation of Anti-inflammatory and Antioxidant Profile of Oleuropein in Experimentally Induced Ulcerative Colitis

Oleuropein is one of the main phenolic secoiridoid of the olive leaf extract, which is known for its antioxidant and anti-inflammatory effects. The main objective of the present study was to investigate the effectiveness of oleuropein in the ulcerative colitis treatment. An experimental study was designed on rats, which were divided into three groups, group 1 (normal control), group 2 (induced for ulcerative colitis and untreated), and group 3 (induced for ulcerative colitis and treated with oleuropein). Colonic tissue samples were collected from all studied groups and the oxidative stress and antioxidant activity were assessed by evaluating malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), myeloperoxidase (MPO), and nitric oxide (NO) levels. The expression levels of pro-inflammatory cytokines such as IL-1β, TNF-α, IL-10, COX-2, iNOS, TGF-β1, MCP-1, and NF-κB, the pro-apoptotic gene Bax, and the anti-apoptotic gene Bcl2 were assessed in colon tissues to evaluate the effectiveness of oleuropein treatment. Oleuropein was effective on reducing the mortality rate and disease activity index. Oleuropein caused a significant reduction in colon MDA, MPO, and NO levels and a significant elevation in SOD, CAT, and GPX levels and induced the down regulation of analyzed proinflammatory cytokines. Also, downregulation of Bax and upregulation of Bcl2 were observed as a result of oleuropein treatment in comparison with untreated acetic acid induced ulcerative colitis group. Oleuropein showed intestinal anti-inflammatory, antioxidant, and anti-apoptotic effects in ulcerative colitis experimental model.

Interventions of natural and synthetic agents in inflammatory bowel disease, modulation of nitric oxide pathways

Inflammatory bowel disease (IBD) refers to a group of disorders characterized by chronic inflammation of the gastrointestinal (GI) tract. The elevated levels of nitric oxide (NO) in serum and affected tissues; mainly synthesized by the inducible nitric oxide synthase (iNOS) enzyme; can exacerbate GI inflammation and is one of the major biomarkers of GI inflammation. Various natural and synthetic agents are able to ameliorate GI inflammation and decrease iNOS expression to the extent comparable with some IBD drugs. Thereby, the purpose of this study was to gather a list of natural or synthetic mediators capable of modulating IBD through the NO pathway. Electronic databases including Google Scholar and PubMed were searched from 1980 to May 2018. We found that polyphenols and particularly flavonoids are able to markedly attenuate NO production and iNOS expression through the nuclear factor κB (NF-κB) and JAK/STAT signaling pathways. Prebiotics and probiotics can also alter the GI microbiota and reduce NO expression in IBD models through a broad array of mechanisms. A number of synthetic molecules have been found to suppress NO expression either dependent on the NF-κB signaling pathway (i.e., dexamethasone, pioglitazone, tropisetron) or independent from this pathway (i.e., nicotine, prednisolone, celecoxib, β-adrenoceptor antagonists). Co-administration of natural and synthetic agents can affect the tissue level of NO and may improve IBD symptoms mainly by modulating the Toll like receptor-4 and NF-κB signaling pathways.

Intestinal anti-inflammatory activity of xique-xique (Pilosocereus gounellei A. Weber ex K. Schum. Bly. Ex Rowl) juice on acetic acid-induced colitis in rats

Inflammatory bowel disease (IBD) is characterized by severe mucosal damage in the intestine and a deregulated immune response. Natural products derived from plants that are rich in bioactive compounds are used by many patients with IBD. Xique-xique (Pilosocereus gounellei) is a cactus of the Caatinga family that has been used by the local population for food and medicinal purposes. The intestinal anti-inflammatory effect of xique-xique cladode juice was evaluated in the present study. A dose of 5 mL kg^-1 had a protective effect on intestinal inflammation, with an improvement in macroscopic damage, and a decrease in pro-inflammatory markers and oxidative stress, in addition to preserving the colonic tissue. Immunohistochemical analysis revealed the downregulation of IL-17, NF-κB, and iNOS, and upregulation of SOCs-1, ZO-1, and MUC-2. These protective effects could be attributed to the phenolic compounds as well as the fibers present in xique-xique juice. Further studies are needed before suggesting the use of xique-xique juice as a new alternative for treating IBD.

Environmentally compatible bioconjugated gold nanoparticles as efficient contrast agents for inflammation-induced cancer imaging

For many cancers, early detection is the key to improve survival and reduce the morbidity, which is associated with radical resections due to late diagnosis. Here, we describe the efficiency of primary antibody-conjugated gold nanoparticles (AuNPs) to specifically target chronic inflammatory processes, specially M2 macrophages, in tissue sections of ulcerative colitis (UC) and steatohepatitis in rats which may lead to colorectal cancer and liver carcinoma, respectively. In this study, we demonstrate that AuNPs synthesized by a simple, inexpensive, and environmentally compatible method can be easily conjugated with the antibodies anti-COX-2, anti-MIF, and Alexa Fluor® 488 (ALEXA) to perform immunofluorescence staining in inflamed tissues. Moreover, we showed that primary antibody-conjugated gold nanoparticles (AuNPs) can be used to target M2 macrophages by flow cytometry. We designed three immunofluorescence staining protocols of tissue section with AuNPs for 30 min and overnight incubation, as well as one flow cytometry protocol of M2 macrophage labeling with AuNPs for 30 min. Immunofluorescence and flow cytometry results suggest that conjugation was achieved by direct adsorption of antibodies on the AuNPs surface. When compared to the standard ALEXA protocol in immunofluorescence (IF) and flow cytometry (FC), our 30-min incubation protocol using AuNPs instead of ALEXA decreased from approximately 23 h to 5 h for IF and from 4 h to 1 h for FC, proving to be less laborious, which makes the method eligible for inflammation-induced cancer diagnostic.

Zeaxanthin exerts protective effects on acetic acid-induced colitis in rats via modulation of pro-inflammatory cytokines and oxidative stress

Ulcerative colitis is a common intestinal inflammatory disease characterized by upregulation of pro-inflammatory cytokines and oxidative stress. Zeaxanthin is a nutritional carotenoid that belongs to the xanthophyll family of pigments. It exerts potent anti-inflammatory and antioxidative effects. The present study aimed to evaluate the effect of zeaxanthin on acetic acid-induced ulcerative colitis in rats. Rats were randomly categorized into five groups: control, zeaxanthin, acetic acid, acetic acid + zeaxanthin, and acetic acid + prednisolone groups. Zeaxanthin (50 mg/kg/day) or prednisolone (5 mg/kg/day) was orally administered for 14 days before induction of ulcerative colitis. On the 15th day, colitis was induced by transrectal administration of 3% acetic acid. The rats were sacrificed 24 h after rectal instillation and their colon tissues were examined. Pretreatment with zeaxanthin significantly reduced disease activity index, wet colon weight, ulcer area, macroscopic scores, and histological changes. Zeaxanthin also effectively downregulated the levels of myeloperoxidase and malondialdehyde, upregulated the enzymatic activity of superoxide dismutase and catalase, and raised glutathione levels. With regard to anti-inflammatory mechanisms, zeaxanthin suppressed tumor necrosis factor-alpha, interferon-gamma, interleukin-6, interleukin-1 beta, and nuclear transcription factor kappa B levels, and inhibited nitric oxide synthase and cyclooxygenase-2 protein expression. Our results indicate that oral administration of zeaxanthin ameliorates acetic acid-induced colitis in rats via antioxidative effects and modulation of pro-inflammatory cytokine and mediator activity. Therefore, zeaxanthin may be an effective therapeutic candidate for the treatment of ulcerative colitis.

Intestinal Anti-Inflammatory Activity of the Aqueous Extract from Ipomoea asarifolia in DNBS-Induced Colitis in Rats

Inflammatory bowel disease is triggered by an uncontrolled immune response associated with genetic, environmental, and intestinal microbiota imbalance. Ipomoea asarifolia (IA), popularly known as “salsa” or “brave salsa”, belongs to the Convolvulaceae family. The aim of this approach was to study the preventive effect of IA aqueous extract in 2,4-dinitrobenzene sulfonic acid (DNBS)-induced colitis in rats. Rats pretreated with IA extract or sulfasalazine (SSZ) received intracolonic instillation of DNBS in 50% ethanol (v/v). IA extract presented a protective effect against intestinal inflammation, with improvement in the disease activity index and macroscopic damage. IA or SSZ significantly reduced myeloperoxidase activity, and also down-regulation of the gene expression of JNK1, NF-κβ-p65, STAT3, and decreased levels of TNFα, IL-1β, and increased IL-10, associated with a significant improvement of oxidative stress, in addition to a reduction in MDA and an increase of glutathione in colonic tissue. The protective effect of the extract was also confirmed in histological evaluation, showing preservation of the colonic cytoarchitecture. Immunohistochemical analysis revealed down-regulation of NF-κβ-p65, iNOS, IL-17, and up-regulation of SOCs-1 and MUC-2. IA extract presents antioxidant and anti-inflammatory intestinal properties, and proved to be a potential application for preventing damage induced by DNBS.

Effect of riboflavin-producing bacteria against chemically induced colitis in mice

AIM

To assess the anti-inflammatory effect associated with individual probiotic suspensions of riboflavin-producing lactic acid bacteria (LAB) in a colitis murine model.

METHODS AND RESULTS

Mice intrarectally inoculated with trinitrobenzene sulfonic acid (TNBS) were orally administered with individual suspensions of riboflavin-producing strains: Lactobacillus (Lact.) plantarum CRL2130, Lact. paracasei CRL76, Lact. bulgaricus CRL871 and Streptococcus thermophilus CRL803; and a nonriboflavin-producing strain or commercial riboflavin. The extent of colonic damage and inflammation and microbial translocation to liver were evaluated. iNOs enzyme was analysed in the intestinal tissues and cytokine concentrations in the intestinal fluids. Animals given either one of the four riboflavin-producing strains showed lower macroscopic and histologic damage scores, lower microbial translocation to liver, significant decreases of iNOs+ cells in their large intestines and decreased proinflammatory cytokines, compared with mice without treatment. The administration of pure riboflavin showed similar benefits. Lact. paracasei CRL76 accompanied its anti-inflammatory effect with increased IL-10 levels demonstrating other beneficial properties in addition to the vitamin production.

CONCLUSION

Administration of riboflavin-producing strains prevented the intestinal damage induced by TNBS in mice.

SIGNIFICANCE AND IMPACT OF THE STUDY

Riboflavin-producing phenotype in LAB represents a potent tool to select them for preventing/treating IBD.

miR-122-SOCS1-JAK2 axis regulates allergic inflammation and allergic inflammation-promoted cellular interactions

The regulatory role of suppressor of cytokine signaling 1 (SOCS1) in inflammation has been reported. However, its role in allergic inflammation has not been previously reported. SOCS1 mediated in vitro and in vivo allergic inflammation. Histone deacetylase-3 (HDAC3), a mediator of allergic inflammation, interacted with SOCS1, and miR-384 inhibitor, a positive regulator of HDAC3, induced features of allergic inflammation in an SOCS1-dependent manner. miRNA array analysis showed that the expression of miR-122 was decreased by antigen-stimulation. TargetScan analysis predicted the binding of miR-122 to the 3′-UTR of SOCS1. miR-122 inhibitor induced in vitro and in vivo allergic features in SOCS1-dependent manner. SOCS1 was necessary for allergic inflammation-promoted enhanced tumorigenic and metastatic potential of cancer cells. SOCS1 and miR-122 regulated cellular interactions involving cancer cells, mast cells and macrophages during allergic inflammation. SOCS1 mimetic peptide, D-T-H-F-R-T-F-R-S-H-S-D-Y-R-R-I, inhibited in vitro and in vivo allergic inflammation, allergic inflammation-promoted enhanced tumorigenic and metastatic potential of cancer cells, and cellular interactions during allergic inflammation. Janus kinase 2 (JAK2) exhibited binding to SOCS1 mimetic peptide and mediated allergic inflammation. Transforming growth factor- Δ1 (TGF-Δ1) was decreased during allergic inflammation and showed an anti-allergic effect. SOCS1 and JAK2 regulated the production of anti-allergic TGF-Δ1. Taken together, our results show that miR-122-SOCS1 feedback loop can be employed as a target for the development of anti-allergic and anti-cancer drugs.