Review of natural products actions on cytokines in inflammatory bowel disease

Diosmetin as a promising natural therapeutic agent: In vivo, in vitro mechanisms, and clinical studies

Diosmetin, a natural occurring flavonoid, is primarily found in citrus fruits, beans, and other plants. Diosmetin demonstrates a variety of pharmacological activities, including anticancer, antioxidant, anti-inflammatory, antibacterial, metabolic regulation, cardiovascular function improvement, estrogenic effects, and others. The process of literature search was done using PubMed, Web of Science and ClinicalTrials databases with search terms containing Diosmetin, content, anticancer, anti-inflammatory, antioxidant, pharmacological activity, pharmacokinetics, in vivo, and in vitro. The aim of this review is to summarize the in vivo, in vitro and clinical studies of Diosmetin over the last decade, focusing on studies related to its anticancer, anti-inflammatory, and antioxidant activities. It is found that DIO has significant therapeutic effects on skin and cardiovascular system diseases, and its research in pharmacokinetics and toxicology is summarized. It provides the latest information for researchers and points out the limitations of current research and areas that should be strengthened in future research, so as to facilitate the relevant scientific research and clinical application of DIO.

Therapeutic effect of Lactobacillus plantarum JS19 on mice with dextran sulfate sodium induced acute and chronic ulcerative colitis

BACKGROUND

Ulcerative colitis is associated with intestinal inflammation and dysbiosis. Previous studies have shown that probiotics are potential agents for treatment of inflammatory bowel disease (IBD). Jiang-shui is a traditional fermented vegetable that is rich in lactic acid bacteria (LABs), but the preventive effect of LABs in jiang-shui on IBD is not yet fully understood.

RESULTS

We isolated 38 LAB strains from jiang-shui, and Lactobacillus plantarum JS19 exhibited the strongest antioxidant activity among them. Our data indicate that oral administration of L. plantarum JS19 significantly inhibited body weight loss, colon shortening and damage, and reduced the disease activity index score in the mice with dextran sulfate sodium (DSS)-induced colitis. In addition, L. plantarum JS19 also alleviated inflammatory responses and oxidative stress through reducing lipid peroxidation, tumor necrosis factor-α expression, and myeloperoxidase activity and enhancing the antioxidant enzyme activity. Importantly, L. plantarum JS19 significantly rebalanced DSS-induced dysbiosis of gut microbiota.

CONCLUSION

L. plantarum JS19 may be used as a potential probiotic to prevent IBD, particularly ulcerative colitis. © 2022 Society of Chemical Industry.

Fasting Protocols Do Not Improve Intestinal Architecture and Immune Parameters in C57BL/6 Male Mice Fed a High Fat Diet

BACKGROUND

The intestinal ecosystem, including epithelium, immune cells, and microbiota, are influenced by diet and timing of food consumption. The purpose of this study was to evaluate various dietary protocols after ad libitum high fat diet (HFD) consumption on intestinal morphology and mucosal immunity.

METHODS

C57BL/6 male mice were fed a 45% high fat diet (HFD) for 6 weeks and then randomized to the following protocols; (1) chow, (2) a purified high fiber diet known as the Daniel Fast (DF), HFD consumed (3) ad libitum or in a restricted manner; (4) caloric-restricted, (5) time-restricted (six hours of fasting in each 24 h), or (6) alternate-day fasting (24 h fasting every other day). Intestinal morphology and gut-associated immune parameters were investigated after 2 months on respective protocols.

RESULTS

Consuming a HFD resulted in shortening of the intestine and reduction in villi and crypt size. Fasting, while consuming the HFD, did not restore these parameters to the extent seen with the chow and DF diet. Goblet cell number and regulatory T cells had improved recovery with high fiber diets, not seen with the HFD irrespective of fasting.

CONCLUSION

Nutritional content is a critical determinant of intestinal parameters associated with gut health.

Poria cocos oligosaccharides ameliorate dextran sodium sulfate-induced colitis mice by regulating gut microbiota dysbiosis

Poria cocos, a widely accepted function food in China, has multiple pharmacological activities. This study aimed to investigate the therapeutic effect and molecular mechanism of Poria cocos oligosaccharides (PCOs) against dextran sodium sulfate (DSS)-induced mouse colitis. In this study, BALB/c mice were treated with 3% (w/v) DSS for seven days to establish a colitis model. The results showed that oral administration of PCOs (200 mg per kg per day) significantly reversed the changes in the physiological indices in colitis mice, including body weight, disease activity index scores (DAI), spleen index, and colon length. From the qRT-PCR assay, it was observed that PCOs suppressed the mRNA expression of pro-inflammatory cytokines, such as Tnf-α, Il-1β, and Il-6. In addition, PCOs protected the intestinal barrier from damage by promoting the expression of mucins and tight junction proteins at both mRNA and protein levels. Upon 16S rDNA sequencing, it was observed that PCO treatment partly reversed the changes in the gut microbiota of colitis mice by selectively regulating the abundance of specific bacteria. And Odoribacter, Muribaculum, Desulfovibrio, Oscillibacter, Escherichia-Shigella, and Turicibacter might be the critical bacteria in improving colitis via PCOs. Finally, using antibiotic mixtures to destroy the intestinal bacteria, we documented that PCO fermentation broth (PCO FB) instead of PCOs prevented the occurrence of colitis in gut microbiota-depleted mice. In conclusion, PCOs showed a protective effect on colitis by reversing gut microbiota dysbiosis. Our study sheds light on the potential application of PCOs as a prebiotic for treating colitis.

Self-assembled micelle derived from pterostilbene ameliorate acute inflammatory bowel disease

PEGylated pterostilbene micelle (PTENPs) with higher bioavailability, biocompatibility, and water solubility were prepared. Then we detected the therapeutic effects in the treatment of inflammatory bowel disease (IBD), together with its potential mechanisms. The anti-oxidant effects and anti-inflammatory effects of PTENPs were determined under in vitro and in vivo conditions. Besides, the cellular toxicity of the PTENPs was determined in vitro, and biocompatibility testing was performed on a colitis mice model to determine its safety. The self-assembled PTENPs showed potency in treating IBD, which was featured by effectively anti-oxidant capacity, inhibition of cellular damages, and an anti-inflammatory role. In addition, PTENPs could inhibit the activation of TLR4, thereby inhibiting the NF-κB and MAPK signaling pathways. Meanwhile, it could protect colonic tissues from oxidative damage, which promoted the remission of colonic inflammation with low toxicity. Compared with free PTE, PTENPs could effectively ameliorate acute IBD with low toxicity, which may be related to the inactivation of TLR4, and inhibition of NF-κB and MAPK signaling pathways.

Lycium barbarum polysaccharides and capsaicin modulate inflammatory cytokines and colonic microbiota in colitis rats induced by dextran sulfate sodium

Active ingredients in the natural products have been considered to be used for alleviating the symptoms of ulcerative colitis, hence the effects of Lycium barbarum polysaccharides (LP) and capsaicin on dextran sulfate sodium (DSS)-induced colitis in rats were investigated. Rats were grouped into normal, DSS induced colitis, and colitis treated with 100 mg LP/kg body weight, 12 mg capsaicin/kg body weight, or combined 50 mg LP/kg body weight and 6 mg capsaicin/kg body weight. Treatment with LP or capsaicin was orally fed by gavage for 4 weeks, and 5% DSS was fed via drinking water for 6 days during week 3. Colon tissue and cecum content were collected for analysis. Treatments with LP and/or capsaicin ameliorated disease activity index scores, severity of colon distortion, and shrinkage of colon length. LP and capsaicin decreased colonic pro-inflammatory cytokine (IFN-γ, IL-17A, and IL-22) levels. Cecal microbiota in colitis rats were enriched with the genus Turicibacter and Lachnospira. The relative abundance of genus Ruminiclostridium_9 and Ruminoclostridium_1 was increased by LP and capsaicin treatment, respectively. Pretreatment with LP or capsaicin inhibits the severity of colonic damage in rats with DSS-induced colitis via anti-inflammation and modulation of colonic microbiota.

Interactions between the gut microbiota-derived functional factors and intestinal epithelial cells - implication in the microbiota-host mutualism

Mutual interactions between the gut microbiota and the host play essential roles in maintaining human health and providing a nutrient-rich environment for the gut microbial community. Intestinal epithelial cells (IECs) provide the frontline responses to the gut microbiota for maintaining intestinal homeostasis. Emerging evidence points to commensal bacterium-derived components as functional factors for the action of commensal bacteria, including protecting intestinal integrity and mitigating susceptibility of intestinal inflammation. Furthermore, IECs have been found to communicate with the gut commensal bacteria to shape the composition and function of the microbial community. This review will discuss the current understanding of the beneficial effects of functional factors secreted by commensal bacteria on IECs, with focus on soluble proteins, metabolites, and surface layer components, and highlight the impact of IECs on the commensal microbial profile. This knowledge provides a proof-of-concept model for understanding of mechanisms underlying the microbiota-host mutualism.

γ-Terpinene complexed with β-cyclodextrin attenuates spinal neuroactivity in animals with cancer pain by Ca2+ channel block

OBJECTIVES

Considering that γ-terpinene (γ-TPN) is a monoterpene found in Cannabis oil, with high lipophilicity and limited pharmacokinetics, our objective was to evaluate whether its complexation in β-cyclodextrin (γ-TPN/β-CD) could improve its physicochemical properties and action on cancer pain, as well as verify the mechanisms of action involved.

METHODS

The γ-TPN/β-CD was prepared and submitted to physicochemical characterization. Animals with sarcoma 180 were treated (vehicle, γ-TPN 50 mg/kg, γ-TPN/β-CD 5 mg/kg or morphine) and assessed for hyperalgesia, TNF-α and IL-1β levels, iNOS and c-Fos activity. The effects of γ-TPN on calcium channels were studied by patch-clamp and molecular docking.

RESULTS

β-CD improved the physicochemical properties and prolonged the anti-hyperalgesic effect of γ-TPN. This compound also reduced the levels of IL-1β, TNF-α and iNOS in the tumour, and c-Fos protein in the spinal cord. In addition, it reduced Ca2+ current, presenting favourable chemical interactions with different voltage-dependent calcium channels.

CONCLUSION

These results indicate that the complexation of γ-TPN into β-CD increases its stability and time effect, reducing spinal neuroactivity and inflammation by blocking calcium channels.

The Role of Tissue-Resident Macrophages in the Development and Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), comprising Crohn’s disease and ulcerative colitis, is a refractory disease with many immune abnormalities and pathologies in the gastrointestinal tract. Because macrophages can distinguish innocuous antigens from potential pathogens to maintain mucosa barrier functions, they are essential cells in the intestinal immune system. With numerous numbers in the intestinal tract, tissue-resident macrophages have a significant effect on the constant regeneration of intestinal epithelial cells and maintaining the immune homeostasis of the intestinal mucosa. They also have a significant influence on IBD through regulating pro-(M1) or anti-inflammatory (M2) phenotype polarization according to different environmental cues. The disequilibrium of the phenotypes and functions of macrophages, disturbed by intracellular or extracellular stimuli, influences the progression of disease. Further investigation of macrophages’ role in the progression of IBD will facilitate deciphering the pathogenesis of disease and exploring novel targets to develop novel medications. In this review, we shed light on the origin and maintenance of intestinal macrophages, as well as the role of macrophages in the occurrence and development of IBD. In addition, we summarize the interaction between gut microbiota and intestinal macrophages, and the role of the macrophage-derived exosome. Furthermore, we discuss the molecular and cellular mechanisms participating in the polarization and functions of gut macrophages, the potential targeted strategies, and current clinical trials for IBD.

A recombinant Bifidobacterium bifidum BGN4 strain expressing the streptococcal superoxide dismutase gene ameliorates inflammatory bowel disease

Background

Inflammatory bowel disease (IBD) is a gastrointestinal disease characterized by diarrhea, rectal bleeding, abdominal pain, and weight loss. Recombinant probiotics producing specific proteins with IBD therapeutic potential are currently considered novel drug substitutes. In this study, a Bifidobacterium bifidum BGN4-SK strain was designed to produce the antioxidant enzymes streptococcal superoxide dismutase (SOD) and lactobacillus catalase (CAT), and a B. bifidum BGN4-pBESIL10 strain was proposed to generate an anti-inflammatory cytokine, human interleukin (IL)-10. In vitro and in vivo efficacy of these genetically modified Bifidobacterium strains were evaluated for colitis amelioration.

Results

In a lipopolysaccharide (LPS)-stimulated HT-29 cell model, tumor necrosis factor (TNF)-α and IL-8 production was significantly suppressed in the B. bifidum BGN4-SK treatment, followed by B. bifidum BGN4-pBESIL10 treatment, when compared to the LPS-treated control. Synergistic effects on TNF-α suppression were also observed. In a dextran sodium sulphate (DSS)-induced colitis mouse model, B. bifidum BGN4-SK treatment significantly enhanced levels of antioxidant enzymes SOD, glutathione peroxidase (GSH-Px) and CAT, compared to the DSS-only group. B. bifidum BGN4-SK significantly ameliorated the symptoms of DSS-induced colitis, increased the expression of tight junction genes (claudin and ZO-1), and decreased pro-inflammatory cytokines IL-6, IL-1β and TNF-α.

Conclusions

These findings suggest that B. bifidum BGN4-SK ameliorated DSS-induced colitis by generating antioxidant enzymes, maintaining the epithelial barrier, and decreasing the production of pro-inflammatory cytokines. Although B. bifidum BGN4-pBESIL10 exerted anti-inflammatory effects in vitro, the enhancement of IL-10 production and alleviation of colitis were very limited.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12934-022-01840-2.

Ethanolic extract from Lepidium virginicum L. ameliorates DNBS-induced colitis in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Lepidium virginicum L. (Brassicaceae) is a plant widely used in traditional Mexican medicine as an expectorant, diuretic, and as a remedy to treat diarrhea and dysentery, infection-derived gastroenteritis. However, there is no scientific study that validates its clinical use as an anti-inflammatory in the intestine.

AIM OF THE STUDY

This study aimed to investigate the anti-inflammatory properties of the ethanolic extract of Lepidium virginicum L. (ELv) in an animal model of inflammatory bowel disease (IBD)-like colitis.

MATERIALS AND METHODS

The 2,4-dinitrobenzene sulfonic acid (DNBS) animal model of IBD was used. Colitis was induced by intrarectal instillation of 200 mg/kg of DNBS dissolved vehicle, 50% ethanol. Control rats only received the vehicle. Six hours posterior to DNBS administration, ELv (3, 30, or 100 mg/kg) was administered daily by gavage or intraperitoneal injection. The onset and course of the inflammatory response were monitored by assessing weight loss, stool consistency, and fecal blood. Colonic damage was evaluated by colon weight/length ratio, histopathology, colonic myeloperoxidase (MPO) activity, and gene expression of proinflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), chemokine C-X-C motif ligand 1 (CXCL-1), and interleukin-6 (IL-6).

RESULTS

Rats treated with DNBS displayed significant weight loss, diarrhea, fecal blood, colon shortening, a significant increase in immune cell infiltration and MPO activity, as well as increased proinflammatory cytokine expression. Intraperitoneal administration of ELv significantly reduced colon inflammation, whereas oral treatment proved to be ineffective. In fact, intraperitoneal ELv significantly attenuated the clinical manifestations of colitis, immune cell infiltration, MPO activity, and pro-inflammatory (CXCL-1, TNF-α, and IL-1β) gene expression in a dose-dependent manner.

CONCLUSION

Traditional medicine has employed ELv as a remedy for common infection-derived gastrointestinal symptoms; however, we hereby present the first published study validating its anti-inflammatory properties in the mitigation of DNBS-induced colitis.

The Antiviral Effects of Jasminin via Endogenous TNF-α and the Underlying TNF-α-Inducing Action

Previous studies have reported that recombinant tumor necrosis factor (TNF)-α has powerful antiviral activity but severe systematic side effects. Jasminin is a common bioactive component found in Chinese herbal medicine beverage “Jasmine Tea”. Here, we report that jasminin-induced endogenous TNF-α showed antiviral activity in vitro. The underlying TNF-α-inducing action of jasminin was also investigated in RAW264.7 cells. The level of endogenous TNF-α stimulated by jasminin was first analyzed by an enzyme-linked immunosorbent assay (ELISA) from the cell culture supernatant of RAW264.7 cells. The supernatants were then collected to investigate the potential antiviral effect against herpes simplex virus 1 (HSV-1). The antiviral effects of jasminin alone or its supernatants were evaluated by a plaque reduction assay. The potential activation of the PI3K–Akt pathway, three main mitogen-activated protein kinases (MAPKs), and nuclear factor (NF)–κB signaling pathways that induce TNF-α production were also investigated. Jasminin induces TNF-α protein expression in RAW264.7 cells without additional stimuli 10-fold more than the control. No significant up-expression of type I, II, and III interferons; interleukins 2 and 10; nor TNF-β were observed by the jasminin stimuli. The supernatants, containing jasminin-induced-TNF-α, showed antiviral activity against HSV-1. The jasminin-stimulated cells caused the simultaneous activation of the Akt, MAPKs, and NF–κB signal pathways. Furthermore, the pretreatment of the cells with the Akt, MAPKs, and NF–κB inhibitors effectively suppressed jasminin-induced TNF-α production. Our research provides evidence that endogenous TNF-α can be used as a strategy to encounter viral infections. Additionally, the Akt, MAPKs, and NF–κB signaling pathways are involved in the TNF-α synthesis that induced by jasminin.

Lycium barbarum Polysaccharides and Capsaicin Inhibit Oxidative Stress, Inflammatory Responses, and Pain Signaling in Rats with Dextran Sulfate Sodium-Induced Colitis

Ulcerative colitis (UC) is an inflammatory disease with chronic relapsing symptoms. This study investigated the effects of Lycium barbarum polysaccharides (LBP) and capsaicin (CAP) in dextran sulfate sodium (DSS)-induced UC rats. Rats were divided into normal, DSS-induced UC, and UC treated with 100 mg LBP/kg bw, 12 mg CAP/kg bw, or 50 mg LBP/kg bw and 6 mg CAP/kg bw. Rats were fed LBP or CAP orally by gavage for 4 weeks, and UC model was established by feeding 5% DSS in drinking water for 6 days during week 3. Oral CAP and mixture significantly reduced disease activity index. Oral LBP significantly decreased serum malondialdehyde, interleukin (IL)-6, colonic tumor necrosis factor (TNF)-α levels, and protein expression of transient receptor potential cation channel V1 (TRPV1) and transient receptor potential ankyrin 1 (TRPA1), but increased serum catalase activity. Oral CAP significantly suppressed serum IL-6, colonic TRPV1 and TRPA1 protein expression, but elevated IL-10 levels, serum superoxide dismutase and catalase activities. The mixture of LBP and CAP significantly reduced serum IL-6, colonic TNF-α and TRPA1 protein. In conclusion, administration of LBP and/or CAP attenuate DSS-induced UC symptoms through inhibiting oxidative stress, proinflammatory cytokines, and protein expression of TRPV1 and TRPA1.

Acteoside, the Main Bioactive Compound in Osmanthus fragrans Flowers, Palliates Experimental Colitis in Mice by Regulating the Gut Microbiota

The present study investigated the effects of Osmanthus fragrans flowers and acteoside on murine colitis and the underlying mechanisms. The O. fragrans flower extract (OFE) and acteoside were administrated to chemically induced colitic mice. The results showed that OFE or acteoside ameliorates intestinal inflammation, oxidative stress, and activation of nuclear factor-κB (NF-κB) in colitic mice. The dysbiosis of the gut microbiome in colitic mice was also partly restored by OFE or acteoside, which was characterized by the alteration of the gut microbiome structure and the enrichment of beneficial bacteria (Akkermansia muciniphila and Bacteroides thetaiotaomicron). Dextran sulfate sodium (DSS)-induced gut metabolome dysfunctions (e.g., sphingosine metabolism and amino acids metabolism) in colitic mice were also partly restored by OFE and acteoside. A fecal microbiota (FM) transplantation study suggested that, compared with the FM from the normal diet-dosed donor mice, the FM from the OFE- or acteoside-dosed donor mice significantly suppressed colitic symptoms.

Diosmetin attenuate experimental ulcerative colitis in rats via suppression of NF-κB, TNF-α and IL-6 signalling pathways correlated with down-regulation of apoptotic events

Introduction

Ulcerative colitis (UC) is a chronic inflammation of colon in which the innermost tissue of colon and rectum develops deep-rooted inflammation. Diosmetin is the aglycone of the flavonoid glycoside diosmin, commonly found in citrus fruits. Therapeutically diosmetin is indicated to demonstrate anticancer, antimicrobial, antioxidant, oestrogenic and anti-inflammatory activity.

Methods

In this research, we studied the action of diosmetin on TNBS (2,4,6-trinitrobenzene sulfonic acid)-induced UC in rats. Male Wister rats were anesthetised with pentobarbital and TNBS introduced by performing an enema. Diosmetin treatment was provided through oral gavage for the next 28 days. Animals were sacrificed on the 29th day and colon tissues were collected for further examinations.

Results

Diosmetin treatment decreased colonic ulceration dramatically and decreased the percentage of inflammation in the colonic mucosa. Depletion of the TNBS assisted of superoxide dismutase and catalase was substantially restricted, while lipid peroxidation was recorded in the colonic tissue as malondialdehyde content was also decreased. After treatment with diosmetin, the occurrence of TNF-α, IL-6and NF-κB was considerably lowered and the number of apoptotic cells observed was significantly reduced.

Conclusion

Taken together, these observations demonstrated the potential of diosmetin against ulcer formation and development.

Saikosaponin-A induces apoptosis of cervical cancer through mitochondria- and endoplasmic reticulum stress-dependent pathway in vitro and in vivo: involvement of PI3K/AKT signaling pathway

Cervical cancer causes considerable mortality in women worldwide. Saikosaponin-A, a triterpenoid glycoside isolated from Bupleurum falcatum, has been proven to exert anti-cancer property. In this study, we evaluated the possibility of saikosaponin-A on cervical cancer in vitro and in vivo. The results showed that saikosaponin-A induced cell death and altered cellular morphology dose-dependently. Saikosaponin-A significantly induced apoptosis in HeLa cells, confirmed by Hoechst 33,342 staining and flow cytometry. Sequentially, saikosaponin-A triggered the mitochondrial-mediated apoptosis demonstrated by deficiency of MMP, induction of Bax/Bcl-2 ratio, leakage of cytochrome c to cytoplasm, and activation of caspase-3. Moreover, ER stress also participated in the apoptosis induced by saikosaponin-A in HeLa cells as indicated by the upregulation of GPR78, CHOP and caspase-12 expression. Furthermore, HeLa cells showed increased expressions of p-PI3K and p-AKT in response to saikosaponin-A treatment. Additionally, saikosaponin-A could inhibit HeLa tumor growth in nude mice and induce apoptosis, reflected by the induction of TUNEL and the expression of cytochrome c, caspase-3 and CHOP confirmed by immunohistochemistry. These findings at least to a certain extent suggested that saikosaponin-A triggered apoptosis through both mitochondrial pathway and ER stress pathway and inhibiting PI3K/Akt signaling, thereby contributing to against cervical cancer. This work provides a new understanding of saikosaponin-A on therapeutic application in treatment of cancer, which has the potential to be a promising candidate therapeutic agent for cervical cancer patients.

Adjunct n-3 Long-Chain Polyunsaturated Fatty Acid Treatment in Tuberculosis Reduces Inflammation and Improves Anemia of Infection More in C3HeB/FeJ Mice With Low n-3 Fatty Acid Status Than Sufficient n-3 Fatty Acid Status

Populations at risk for tuberculosis (TB) may have a low n-3 polyunsaturated fatty acid (PUFA) status. Our research previously showed that post-infection supplementation of n-3 long-chain PUFA (LCPUFA) in TB without TB medication was beneficial in n-3 PUFA sufficient but not in low-status C3HeB/FeJ mice. In this study, we investigated the effect of n-3 LCPUFA adjunct to TB medication in TB mice with a low compared to a sufficient n-3 PUFA status. Mice were conditioned on an n-3 PUFA-deficient (n-3FAD) or n-3 PUFA-sufficient (n-3FAS) diet for 6 weeks before TB infection. Post-infection at 2 weeks, both groups were switched to an n-3 LCPUFA [eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA)] supplemented diet and euthanized at 4- and 14- days post-treatment. Iron and anemia status, bacterial loads, lung pathology, lung cytokines/chemokines, and lung lipid mediators were measured. Following 14 days of treatment, hemoglobin (Hb) was higher in the n-3FAD than the untreated n-3FAS group (p = 0.022), whereas the n-3FAS (drug) treated control and n-3FAS groups were not. Pro-inflammatory lung cytokines; interleukin-6 (IL-6) (p = 0.011), IL-1α (p = 0.039), MCP1 (p = 0.003), MIP1- α (p = 0.043), and RANTES (p = 0.034); were lower, and the anti-inflammatory cytokine IL-4 (p = 0.002) and growth factor GMCSF (p = 0.007) were higher in the n-3FAD compared with the n-3FAS mice after 14 days. These results suggest that n-3 LCPUFA therapy in TB-infected mice, in combination with TB medication, may improve anemia of infection more in low n-3 fatty acid status than sufficient status mice. Furthermore, the low n-3 fatty acid status TB mice supplemented with n-3 LCPUFA showed comparatively lower cytokine-mediated inflammation despite presenting with lower pro-resolving lipid mediators.

Phytochemicals Targeting JAK-STAT Pathways in Inflammatory Bowel Disease: Insights from Animal Models

Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract that consists of Crohn’s disease (CD) and ulcerative colitis (UC). Cytokines are thought to be key mediators of inflammation-mediated pathological processes of IBD. These cytokines play a crucial role through the Janus kinase (JAK) and signal transducer and activator of transcription (STAT) signaling pathways. Several small molecules inhibiting JAK have been used in clinical trials, and one of them has been approved for IBD treatment. Many anti-inflammatory phytochemicals have been shown to have potential as new drugs for IBD treatment. This review describes the significance of the JAK–STAT pathway as a current therapeutic target for IBD and discusses the recent findings that phytochemicals can ameliorate disease symptoms by affecting the JAK–STAT pathway in vivo in IBD disease models. Thus, we suggest that phytochemicals modulating JAK–STAT pathways are potential candidates for developing new therapeutic drugs, alternative medicines, and nutraceutical agents for the treatment of IBD.

6,7-Dihydroxy-2,4-Dimethoxyphenanthrene from Chinese Yam Peels Alleviates DSS-Induced Intestinal Mucosal Injury in Mice via Modulation of the NF-κB/COX-2 Signaling Pathway

In this study, we evaluated the protective effect and molecular mechanism of a dominant phenanthrene, (6,7-dihydroxy-2,4-dimethoxyphenanthrene, CYP4), from Chinese yam peels on intestinal epithelial integrity. Three doses of Chinese yam phenolic extract (CYPE) and Chinese yam phenanthrene 4 (CYP4) were administered to BALB/c mice for 7 days before dextran sulfate sodium (DSS) treatment, with berberine hydrochloride as a positive control (PC). Results showed that both disease activity indexes (DAIs), histological damage score (HDS) and survival rate in DSS mice, were improved with preintervention of CYPE and CYP4, which exhibited better efficiency than PC. Further studies showed that administration of CYP4 downregulated the oxidative stress-associated factors, MPO and NO, and improved tight junction protein occludin. Besides, the CYP4 treatment substantially downregulated the caspase-3 expression and the apoptosis rate of intestinal epithelial cells. In addition, the CYP4 treatment ameliorated the production of inflammatory cytokines including TNF-α, IFN-γ, IL-10, and IL-23 in the colon. Furthermore, the protein expression of ERK1/2, NF-κB p65, pNF-κB, and COX-2 was suppressed in CYE4 groups as compared with that in model control (MC). These findings suggested that CHP4 could effectively inhibit the activation of NF-κB/COX-2 in an experimental UC model in vivo. It was demonstrated for the first time that CYPE and CYP4 protected intestinal mucosa from damage and prevented DSS-induced colitis in mice. CYP4 was one of the active principles obligatory for the biological effect of Chinese yam in protecting intestinal health. These findings indicated that CYP4 might be a promising and useful approach for treatment of UC in humans.

Nano-encapsulation of hydroxytyrosol into formulated nanogels improves therapeutic effects against hepatic steatosis: An in vitro study

Nanomaterials hold promise as a straightforward approach for enhancing the performance of bioactive compounds in several healthcare scenarios. Indeed, nanoencapsulation represents a valuable strategy to preserve the bioactives, maximizing their bioavailability. Here, a nanoencapsulation strategy for the treatment of nonalcoholic fatty liver disease (NAFLD) is presented. NAFLD represents the most common chronic liver disease in Western societies, and still lacks an effective therapy. Hydroxytyrosol (HT), a naturally occurring polyphenol, has been shown to protect against hepatic steatosis through its lipid-lowering, antioxidant and anti-inflammatory activities. However, the efficient delivery of HT to hepatocytes remains a crucial aspect: the design of smart nanogels appears as a promising tool to promote its intracellular uptake. In this paper, we disclose the synthesis of nanogel systems based on polyethylene glycol and polyethyleneimine which have been tested in an in vitro model of hepatic steatosis at two different concentrations (0.1 mg/mL and 0.5 mg/mL), taking advantage of high-content analysis tools. The proposed HT-loaded nanoscaffolds are non-toxic to cells, and their administration showed a significant decrease in the intracellular triglyceride levels, restoring cell viability and outperforming the results achievable with HT in its non-encapsulated form. Moreover, nanogels do not induce oxidative stress, thus demonstrating their biosafety. Overall, the formulated nanogel system achieves superior performance compared to conventional drug administration routes and hence represents a promising strategy for the management of NAFLD.

Indol-3-Carbinol and Quercetin Ameliorate Chronic DSS-Induced Colitis in C57BL/6 Mice by AhR-Mediated Anti-Inflammatory Mechanisms

Inflammatory bowel diseases (IBD), such as Crohn’s disease and ulcerative colitis, are multifactorial inflammatory disorders of the gastrointestinal tract, characterised by abdominal cramps, bloody diarrhoea, and anaemia. Standard therapies, including corticosteroids or biologicals, often induce severe side effects, or patients may develop resistance to those therapies. Thus, new therapeutic options for IBD are urgently needed. This study investigates the therapeutic efficacy and safety of two plant-derived ligands of the aryl hydrocarbon receptor (AhR), quercetin (Q), and indol-3-carbinol (I3C), using a translationally relevant mouse model of IBD. Q and I3C are administered by gavage to C57BL/6 wild-type or C57BL/6 Ahr^-/- mice suffering from chronic colitis, induced by dextran sulphate sodium (DSS). The course of the disease, intestinal histopathological changes, and in-situ immunological phenotype are scored over 25 days. Our results show that both Q and I3C improved significantly clinical symptoms in moderate DSS colitis, which coincides with a significantly reduced histopathological score. Even in severe DSS colitis I3C, neither Q nor the therapy control 6-thioguanine (6-TG) can prevent a fatal outcome. Moreover, treatment with Q or I3C restored in part DSS-induced loss of epithelial integrity by induction of tight-junction proteins and reduced significantly gut inflammation, as demonstrated by colonoscopy, as well as by immunohistochemistry revealing lower numbers of neutrophils and macrophages. Moreover, the number of Th17 cells is significantly reduced, while the number of Treg cells is significantly increased by treatment with Q or I3C, as well as 6-TG. Q- or I3C-induced amelioration of colitis is not observed in Ahr^-/- mice suggesting the requirement of AhR ligation and signalling. Based on the results of this study, plant-derived non-toxic AhR agonists can be considered promising therapeutics in IBD therapy in humans. However, they may differ in terms of efficacy; therefore, it is indispensable to study the dose-response relationship of each individual AhR agonist also with regard to potential adverse effects, since they may also exert AhR-independent effects.

Systems pharmacology approach uncovers Ligustilide attenuates experimental colitis in mice by inhibiting PPARγ-mediated inflammation pathways

Inflammatory bowel disease (IBD) is a chronic idiopathic disorder causing inflammation in the gastro-intestinal tract, which is lack of effective drug targets and medications. To identify novel therapeutic agents against consistent targets, we exploited a systems pharmacology-driven framework that incorporates drug-target networks of natural product and IBD disease genes. Our in silico approach found that Ligustilide (LIG), one of the major active components of Angelica acutiloba and Cnidium Officinale, potently attenuated IBD. The following in vivo and in vitro results demonstrated that LIG prevented experimental mice colitis induced by dextran sulfate sodium (DSS) via suppressing inflammatory cell infiltration, the activity of MPO and iNOS, and the expression and production of IL-1β, IL-6, and TNF-α. Subsequently, the network analysis helped to validate that LIG alleviated colitis by inhibiting NF-κB and MAPK/AP-1 pathway through activating PPARγ, which were further confirmed in RAW 264.7 cells and bone marrow-derived macrophages in vitro. In summary, this study reveals that LIG activated PPARγ to inhibit the activation of NF-κB and AP-1 signaling thus eventually alleviated DSS-induced colitis, which has promising activities and may serve as a candidate for the treatment of IBD.Graphical abstract This study suggested novel computational and experimental pharmacology approaches to identify potential IBD therapeutic agents by exploiting polypharmacology of natural products. We demonstrated that LIG could attenuate inflammation in IBD by inhibiting NF-κB and AP-1 pathways via PPARγ activation to reduce the expression of pro-inflammatory cytokines in macrophages. These findings offer comprehensive pre-clinical evidence that LIG may serve as a promising candidate for IBD therapy in the future. Graphical headlights: 1. Systems pharmacology uncovered Ligustilide attenuates experimental colitis in mice. 2. Network-based analysis predicted the mechanism of Ligustilide against IBD, which was validated by inhibiting PPARγ-mediated inflammation pathways. 3. Ligustilide activated PPARγ to inhibit NF-κB and AP-1 activation thus eventually alleviated DSS-induced colitis.4. Ligustilide has promising activities and may serve as a candidate for the treatment of IBD.

Baitouweng Decoction Ameliorates Ulcerative Colitis in Mice Partially Attributed to Regulating Th17/Treg Balance and Restoring Intestinal Epithelial Barrier

Ulcerative colitis (UC) is a chronic intestinal disease with unclear pathogenesis. With an increasing global prevalence over the past two decades, UC poses a serious threat to public health. Baitouweng decoction (BTW), a traditional Chinese medicine, has been shown to have good clinical efficacy for treating intestinal inflammation. Yet, the efficacy of BTW in UC and the underlying mechanism remain unclear. The current study aimed to determine whether BTW suppressed intestinal inflammation in mice and the potential mechanism. We used a dextran sulfate sodium (DSS)-induced murine colitis model to test the anti-inflammatory efficacy of BTW. Clinical symptoms were scored by the disease activity index (DAI), and the colon length and pathological changes in colon tissue were also used to further evaluate the efficacy of BTW. Precisely how BTW affected immune function and the intestinal barrier of UC mice was also examined. BTW significantly reduced DAI score and colonic pathological damage. BTW regulated the balance between T helper (Th)17 and regulatory T (Treg) cells, decreased interleukin (IL)-1β, IL-6, and tumor necrosis factor-α, and increased IL-10 levels. BTW reduced intestinal permeability of UC mice, increased expression of tight junction proteins (occludin and zonula occludens-1), and decreased expression of phospho-nuclear factor (p-NF)-κB and phospho-extracellular signal-regulated kinase (p-ERK) in the colon. BTW inhibited the ERK/p-NF-κB signaling pathway and suppressed expression of cyclo-oxygenase-2 and inducible NO synthase in lipopolysaccharide-activated RAW 264.7 cells. BTW significantly promoted the synthesis of short-chain fatty acids in the gut, particularly acetate, propionate, isobutyric acid, and isovalerate. The results suggest that BTW can protect against DSS-induced UC. The mechanism may be partially attributed to regulating the balance of Th17/Treg cells and restoring the intestinal epithelial barrier.

Wide-scope screening for pharmaceutically active substances in a leafy vegetable cultivated under biogas slurry irrigation

The use of livestock waste for the production of biogas and the application of biogas slurry to agricultural soil can resolve livestock waste problems and reduce synthetic fertiliser use. However, the migration of veterinary drugs to land and crops resulting from biogas slurry irrigation is a potential food safety concern. This study employed an ultra-performance liquid chromatography coupled with quadrupole-time of flight high-resolution mass spectrometry system for wide-scope suspect screening of pharmaceutically active substances on crop cultivated under biogas slurry irrigation. Briefly, a total of 22 pak choi samples were obtained from a greenhouse farmed in tropical south Taiwan between March 2019 and March 2020. Molecular spectra and fragmented ions (between m/z 70 and 1100) were acquired. Ion features were searched and matched with a library consisting of 1068 compounds. The matrixes in the crop production environment including soil, livestock wastewater, biogas slurry, and groundwater were included in this study to elucidate potential sources of the pharmaceutically active substances. Results demonstrated 23 suspects were matched with high mass accuracy (mass error within ±5.0 ppm) in pak choi. The detection of both bufexamac and nandrolone were confirmed using standards, where a new system of identification points was applied. Nandrolone was detected throughout the pak choi samples as well as livestock wastewater. Tetracycline, macrolide, and sulfonamide antibiotics were presented in biogas slurry and soil but not pak choi. This is the first study to reveal the presence of multiclass pharmaceutically active substances in a crop supplied as food. Such findings suggest that anabolics and antibiotics should be closely monitored in the corps irrigated by biogas slurry in future.

Flos lonicerae flavonoids attenuate experimental ulcerative colitis in rats via suppression of NF-κB signaling pathway

This study sought to isolate active Flos lonicerae flavonoids and evaluate their anti-oxidative and anti-inflammatory effects as well as investigate the molecular mechanistic action of these flavonoids in the rat model of ulcerative colitis (UC). Total flavonoids and three flavonoids (hyperoside, lonicerin, and luteolin) were isolated from honeysuckle and purified via column purification. Rat model of UC was established via 2,4,6-trinitrobenzene sulfonic acid (TNBS) intoxication. The anti-oxidative and anti-inflammatory effects of the three flavonoids against TNBS-induced UC were evaluated by measuring appropriate biomarkers via assay kit. The effects of hyperoside, lonicerin, and luteolin on the regulation of nuclear factor-kappa B (NF-κB) pathway were investigated using Western blot (WB) and real-time polymerase chain reaction (RT-PCR) while their protective effects on UC were also elucidated. Pretreatment with flavonoids (hyperoside, lonicerin, and luteolin at 25-100 mg/kg) and sulfasalazine (SSZ, positive control at 100 mg/kg) substantially attenuated TBNS-induced UC. Also, the flavonoids significantly reduced the levels of respective serum oxidative and proinflammatory markers such as superoxide dismutase (SOD), myeloperoxidase (MPO), malondialdehyde (MDA), prostaglandins E2 (PGE2), tumor necrosis factor-alpha (TNF-α), interleukin-beta (IL-β), and C-reactive protein (CRP). In addition, the flavonoids remarkably inhibited the expression of NF-κB signaling pathway. F. lonicerae flavonoids (hyperoside, lonicerin, and luteolin) demonstrated potent anti-UC activities in TBNS-induced UC rat model via anti-oxidative and anti-inflammatory effects through the inhibition of NF-κB signaling pathway.

Nutritional Interventions Using Functional Foods and Nutraceuticals to Improve Inflammatory Bowel Disease

The gastrointestinal tract, the second largest organ in the body, plays an important role in nutrient and mineral intake through the intestinal barrier. Dysfunction of intestinal permeability and related disorders commonly occur in patients with inflammatory bowel disease (IBD), one of the health problems in the Western societies that are considered to be mainly due to the Western diet. Although the exact etiology of IBD has not been elucidated, environmental and genetic factors may be involved in its pathogenesis. Many synthetic or biological drugs, such as 5-aminosalicylic acid corticosteroids as anti-inflammatory drugs, have been used clinically to treat IBD. However, their long-term use exhibits some adverse health consequences. Therefore, many researchers have devised alternative therapies to overcome this problem. Many studies have revealed that some functional nutrients in nature can relieve gastrointestinal inflammation by controlling proinflammatory cytokines. In this study, we review the ability of functional nutraceuticals such as phytochemicals, fatty acids, and bioactive peptides in improving IBD by regulating its underlying pathogenic mechanisms.

Quercetin and hydroxytyrosol as modulators of hepatic steatosis: A NAFLD-on-a-chip study

Organs-on-chip (OoCs) are catching on as a promising and valuable alternative to animal models, in line with the 3Rs initiative. OoCs enable the creation of three-dimensional (3D) tissue microenvironments with physiological and pathological relevance at unparalleled precision and complexity, offering new opportunities to model human diseases and to test the potential therapeutic effect of drugs, while overcoming the limited predictive accuracy of conventional 2D culture systems. Here, we present a liver-on-a-chip model to investigate the effects of two naturally occurring polyphenols, namely quercetin and hydroxytyrosol, on nonalcoholic fatty liver disease (NAFLD) using a high-content analysis readout methodology. NAFLD is currently the most common form of chronic liver disease; however, its complex pathogenesis is still far from being elucidated, and no definitive treatment has been established so far. In our experiments, we observed that both polyphenols seem to restrain the progression of the free fatty acid-induced hepatocellular steatosis, showing a cytoprotective effect due to their antioxidant and lipid-lowering properties. In conclusion, the findings of the present work could guide novel strategies to contrast the onset and progression of NAFLD.

Bacterial Natural Compounds with Anti-Inflammatory and Immunomodulatory Properties (Mini Review)

Inflammation is part of the body's complex biological response to harmful stimuli such as damaged cells, pathogens, or irritants. It is a protective response involving blood cells, immune cells, and molecular mediators. The inflammation not only can eliminate the primary cause of cell injury but also clears out necrotic cells, tissue damaged from the original insults and inflammatory process. Furthermore, it can initiate tissue repair. Pro-inflammatory cytokines are produced predominantly by activated macrophages and are involved in the up-regulation of inflammatory reactions. They are involved in further regulating inflammatory reactions. There is ample evidence that some pro-inflammatory cytokines, such as interleukin 1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α), are involved in the pathological pain process. Some of the natural compounds promote cytokines production and inhibit inflammatory responses. The natural compounds which are produced from microorganisms such as omega-3 fatty acid, cyclic peptide, antimicrobial peptide, oligosaccharides, and polysaccharides can reduce inflammation and could be easily incorporated into the diet without any adverse effects. For example, SCFA (short-chain fatty acids), peptide bacteriocin, and polycyclic peptide bacteriocin (nisin) could be used in the treatment of atherosclerosis, orthopedic postoperative infections, and mycobacterium tuberculosis infection, respectively. Also, fatty acids (saturated and unsaturated fatty acids) can be introduced as anti-inflammatory drugs. This review article summarizes bacterial natural compounds with modulating effects on cytokines that are surveyed which may have potential anti-inflammatory drug-like activity.

Natural Product-Based Nanomedicine in Treatment of Inflammatory Bowel Disease

: Many synthetic drugs and monoclonal antibodies are currently in use to treat Inflammatory Bowel Disease (IBD). However, they all are implicated in causing severe side effects and long-term use results in many complications. Numerous in vitro and in vivo experiments demonstrate that phytochemicals and natural macromolecules from plants and animals reduce IBD-related complications with encouraging results. Additionally, many of them modify enzymatic activity, alleviate oxidative stress, and downregulate pro-inflammatory transcriptional factors and cytokine secretion. Translational significance of natural nanomedicine and strategies to investigate future natural product-based nanomedicine is discussed. Our focus in this review is to summarize the use of phytochemicals and macromolecules encapsulated in nanoparticles for the treatment of IBD and IBD-associated colorectal cancer.

Camellia sinensis and Litsea coreana Ameliorate Intestinal Inflammation and Modulate Gut Microbiota in Dextran Sulfate Sodium-Induced Colitis Mice

SCOPE

Polyphenol-enriched herbal extracts have been proved as alternative therapeutic strategies for experimentally induced colitis. The in vivo and in vitro anti-inflammatory effects of Camellia sinensis (green, white, yellow, oolong, black, and dark tea) and Litsea coreana (hawk tea) are comparatively explored.

METHODS AND RESULTS

HPLC analysis confirms dissimilarities among phytochemical compositions of these teas. The tea extracts (TEs) significantly decrease the production of pro-inflammatory cytokines (IL-6, IL-12, and tumor necrosis factor-α) and increase the anti-inflammatory cytokines (IL-10) in LPS-stimulated RAW 264.7 macrophages and a dextran sodium sulfate (DSS)-induced colitis mouse model. The treatment of TEs in colitis mice can ameliorate colon inflammation, pro-oxidative enzyme activity, colon integrity, and suppress the activation of nuclear factor-κB. Of note, green TE significantly attenuates the DSS-induced decrease in richness and diversity of gut microbiota. Moreover, TEs are capable of exerting a prebiotic effect on gut microbiota by increasing the abundance of potentially beneficial bacteria (e.g., Faecalibaculum, and Bifidobacterium), and decreasing the abundance of potentially harmful bacteria (e.g., Bacteroids, and Mucispirillum). TEs restore the decreased production of SCFAs in the feces of colitic mice.

CONCLUSION

The treatment of seven types of tea can alleviate DSS-induced colitis in mice, and modulate the dysbiosis of gut microbiota in colitis mice.

Protective effects of flavonoid composition rich P. subpeltata Ortega. on indomethacin induced experimental ulcerative colitis in rat models of inflammatory bowel diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Polyphenolics (flavonoid and phenolic) rich plants are the effective source for the treatment of acute and chronic degenerative diseases including inflammatory bowel disease.

OBJECTIVE

This study was aimed to examine the effects of polyphenolics rich leaf acetone extract of P. subpeltata against the indomethacin induced ulcerative colitis in rats.

MATERIALS AND METHODS

Two consecutive days administration of indomethacin produced chronic inflammation in GIT tissues of rats. Further, the plant extract 200 and 400 mg/kg treatment were continued until 11th day. Then hematological, enzymatic antioxidants, MPO and histological evaluations were analyzed. Moreover, the extracts were treated with RAW267.4 cells for the cytotoxicity, NO and TNF-α analysis.

RESULTS

The obtained results revealed, that higher dose of the plant extract dropped neutrophil infiltration followed by inhibiting the MPO enzyme levels and controls the enzymatic antioxidants such as SOD, CAT, GSH and LPO. RAW cells study also proved that the plant extract effectively inhibits NO and TNF-α production.

CONCLUSIONS

Thus, these results suggest that P. subpeltata extract may have therapeutic potential for the treatment of IBD although further clinical research is still warranted.

Grape peel powder attenuates the inflammatory and oxidative response of experimental colitis in rats by modulating the NF-κB pathway and activity of antioxidant enzymes

Most phenolic compounds and dietary fiber reach intact to the colon. We hypothesized that grape peel powder (GPP), a rich source of these bioactive compounds, modulates inflammatory and oxidative pathways collaborating to attenuate colonic damage in experimental colitis. To determine which bioactive fraction would be responsible for this effect, the aim of this study was to evaluate the effect of dietary supplementation with whole GPP or the isolated bioactive-rich fractions from GPP (extractable polyphenols [EP], dietary fiber and fiber-bound polyphenols [NEP-F], and dietary fiber) in rats with experimental colitis. Colitis was induced by intrarectal injection of 2,4,6-trinitrobenzene sulfonic acid (TNBS) after 15 days of dietary supplementation. EP diet did not reverse the decrease in feed intake and indeed worsened colon shortening and increased spleen weight; however, these effects were not observed for the GPP group, which had polyphenols associated to the matrix besides the extractable ones. Colitis impaired the activity of colonic antioxidant enzymes and increased lipid peroxidation, protein oxidation, nitric oxide (NO) levels, and proinflammatory cytokines in serum and in the colon tissue. GPP restored the activity of antioxidant enzymes and decreased colon oxidation and NO levels. All grape peel fractions reduced the protein expression of the inhibitor of kappa kinase beta and NO levels in colon tissue, but only NEP-F reduced the expression of phosphorylated nuclear factor kappa B and myeloperoxidase activity. Results demonstrated that GPP attenuates inflammatory and oxidative response in TNBS-induced colitis by downregulating the nuclear factor kappa B pathway and upregulating antioxidant enzymes, with NEP-F being the fraction most likely associated to these protective effects.

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.

Citrus fruits and their flavonoids in inflammatory bowel disease: an overview

Inflammatory bowel disease (IBD), with its major manifestations being Crohn's disease and ulcerative colitis, belongs to the gastrointestinal inflammatory disorders, whose main therapeutic approach is represented by synthetic anti-inflammatory drugs. However, they are often accompanied by many side effects that shifted the interest of the scientific community towards natural products. In this context, several studies asserted the anti-IBD effects of Citrus fruits and their flavonoids, thus the aim of the present review is to provide robust evidence favouring their role in the prevention and treatment of IBD. Key mechanisms relate to their anti-inflammatory and antioxidant properties, as well as their ability to modulate gut microbiota. All the findings collected in this review, lay the foundations for further studies in human with the aim of evaluating the concrete applicability as a novel preventive and therapeutic approach of Citrus fruits and their flavonoids.[Figure: see text].

Potential Role of Flavonoids in Treating Chronic Inflammatory Diseases with a Special Focus on the Anti-Inflammatory Activity of Apigenin

Inflammation has been reported to be intimately linked to the development or worsening of several non-infectious diseases. A number of chronic conditions such as cancer, diabetes, cardiovascular disorders, autoimmune diseases, and neurodegenerative disorders emerge as a result of tissue injury and genomic changes induced by constant low-grade inflammation in and around the affected tissue or organ. The existing therapies for most of these chronic conditions sometimes leave more debilitating effects than the disease itself, warranting the advent of safer, less toxic, and more cost-effective therapeutic alternatives for the patients. For centuries, flavonoids and their preparations have been used to treat various human illnesses, and their continual use has persevered throughout the ages. This review focuses on the anti-inflammatory actions of flavonoids against chronic illnesses such as cancer, diabetes, cardiovascular diseases, and neuroinflammation with a special focus on apigenin, a relatively less toxic and non-mutagenic flavonoid with remarkable pharmacodynamics. Additionally, inflammation in the central nervous system (CNS) due to diseases such as multiple sclerosis (MS) gives ready access to circulating lymphocytes, monocytes/macrophages, and dendritic cells (DCs), causing edema, further inflammation, and demyelination. As the dearth of safe anti-inflammatory therapies is dire in the case of CNS-related disorders, we reviewed the neuroprotective actions of apigenin and other flavonoids. Existing epidemiological and pre-clinical studies present considerable evidence in favor of developing apigenin as a natural alternative therapy against chronic inflammatory conditions.

A systematic review of nano formulation of natural products for the treatment of inflammatory bowel disease: drug delivery and pharmacological targets

Inflammatory bowel diseases (IBD), which is classified into Crohn's disease and ulcerative colitis, are among chronic gastrointestinal diseases with unknown pathogenesis. Diverse strategies have been applied for the treatment of this chronic disease. However, selective and site-specific routes of drug delivery to the inflamed location of the colon remain of high importance. Consequently, the application and effects of natural products in the form of nanoformulation and stimuli responsive nanoparticles as a novel strategy for the treatment of IBD are discussed in this review article. This approach may potentially overcome some complications that are associated with conventional means of colon drug delivery. Meanwhile, in vitro and in vivo studies pave the way for understanding of the mechanism that lies behind this chronic relapsing disease and potentially more effective treatment. Graphical abstract ᅟ.

Monoterpenes modulating cytokines - A review

Inflammatory response can be driven by cytokine production and is a pivotal target in the management of inflammatory diseases. Monoterpenes have shown that promising profile as agents which reduce the inflammatory process and also modulate the key chemical mediators of inflammation, such as pro and anti-inflammatory cytokines. The main interest focused on monoterpenes were to develop the analgesic and anti-inflammatory drugs. In this review, we summarized current knowledge on monoterpenes that produce anti-inflammatory effects by modulating the release of cytokines, as well as suggesting that which monoterpenoid molecules may be most effective in the treatment of inflammatory disease. Several different inflammatory markers were evaluated as a target of monoterpenes. The proinflammatory and anti-inflammatory cytokines were found TNF-α, IL-1β, IL-2, IL-5, IL-4, IL-6, IL-8, IL-10, IL-12 IL-13, IL-17A, IFNγ, TGF-β1 and IFN-γ. Our review found evidence that NF-κB and MAPK signaling are important pathways for the anti-inflammatory action of monoterpenes. We found 24 monoterpenes that modulate the production of cytokines, which appears to be the major pharmacological mechanism these compounds possess in relation to the attenuation of inflammatory response. Despite the compelling evidence supporting the anti-inflammatory effect of monoterpenes, further studies are necessary to fully explore their potential as anti-inflammatory compounds.

Cocoplum (Chrysobalanus icaco L.) anthocyanins exert anti-inflammatory activity in human colon cancer and non-malignant colon cells

Cocoplum (Chrysobalanus icaco L.) (CP) is an anthocyanin-rich fruit found in tropical areas around the globe. CP polyphenols are associated with beneficial effects on health, including reduction of inflammation and oxidative stress. Due to its functional properties, the consumption of this fruit may be beneficial in the promotion of human health and reduce the risk for chronic diseases. The objective of this study was to assess the anti-inflammatory and anti-proliferative activities of anthocyanins extracted from CP (1.0 to 20.0 μg ml^-1 gallic acid equivalents [GAE]) in CCD-18Co non-malignant colonic fibroblasts and HT-29 colorectal adenocarcinoma cells. Tumor necrosis factor alpha (TNF-α, 10 ng mL^-1) was used to induce inflammation in CCD-18Co cells. CP anthocyanins were identified and quantified using HPLC-ESI-MSⁿ. The chemical analysis of CP extract identified delphinidin, cyanidin, petunidin and peonidin derivatives as major components. Cell proliferation was suppressed in HT-29 cells at 10.0 and 20.0 μg ml^-1 GAE and this was accompanied by increased intracellular ROS production as well as decreased TNF-α, IL-1β, IL-6, and NF-κB1 expressions at 20.0 μg ml^-1 GAE. Within the same concentration range, there was no cytotoxic effect of CP anthocyanins in CCD-18Co cells and TNF-α-induced intracellular ROS-production was decreased by 17.3%. IL-1β, IL-6 and TNF-α protein expressions were also reduced in TNF-α-treated CCD-18Co cells by CP anthocyanins at 20.0 μg ml^-1 GAE. These results suggest that cocoplum anthocyanins possess cancer-cytotoxic and anti-inflammatory activities in both inflamed colon and colon cancer cells.

Intake of Protein Hydrolysates and Phenolic Fractions Isolated from Flaxseed Ameliorates TNBS-Induced Colitis

SCOPE

In the attempt to develop new therapeutic treatments for colitis, fractions containing phenolic compound isolate (Phi) and phenolic reduced-flaxseed protein hydrolysate (phr-FPH) from flaxseed are evaluated for their effects on the in vitro production of pro-inflammatory mediators and on the course of experimental colitis.

METHODS AND RESULTS

The anti-inflammatory effects of Phi and phr-FPH from flaxseeds are studied in RAW264.7 cells and in trinitrobenzene sulphonic acid (TNBS) colitis model. It is observed that the incubation with Phi or phr-FPH result in lower levels of tumor necrosis factor α and nitric oxide in macrophages stimulated with bacterial lipopolysaccharide + interferon-γ. Prophylactic and therapeutic treatments with Phi and phr-FPH, respectively, greatly contribute to the prevention of weight loss and colon inflammation in colitic BALB/c mice. T cell proliferation, expansion of TH1 and TH17 cells, and pro-inflammatory cytokines are lower, whereas Treg cells are higher in spleen cell cultures from Phi-treated mice. In addition, therapeutic phr-FPH treatment is able to reduce the expansion of TH17 in splenic cell cultures.

CONCLUSION

The consumption of phenolic and protein compounds extracted from flaxseeds has a protective effect on TNBS-induced colitis, and may be useful in the control of other inflammatory disorders.

Diets, functional foods, and nutraceuticals as alternative therapies for inflammatory bowel disease: Present status and future trends

Inflammatory bowel disease (IBD) is a serious health concern among western societies. The disease is also on the rise in some East Asian countries and in Australia. Health professionals and dietitians around the world are facing an unprecedented challenge to prevent and control the increasing prevalence of IBD. The current therapeutic strategy that includes drugs and biological treatments is inefficient and are associated with adverse health consequences. In this context, the use of natural products is gaining worldwide attention. In vivo studies and clinical evidence suggest that well-planned dietary regimens with specific nutrients can alleviate gastrointestinal inflammation by modulating inflammatory cytokines, such as tumor necrosis factor α (TNF-α), interleukin 1 (IL-1), IL-6, IL-1β, and IL-10. Alternatively, the avoidance of high-fat and high-carbohydrate diets is regarded as an effective tool to eliminate the causes of IBD. Many functional foods and bioactive components have received attention for showing strong therapeutic effects against IBD. Both animal and human studies suggest that bioactive functional foods can ameliorate IBD by downregulating the pro-inflammatory signaling pathways, such as nuclear factor κB, STAT1, STAT6, and pro-inflammatory cytokines, including IL-1β, IL-4, IL-6, COX-2, TNF-α, and interferon γ. Therefore, functional foods and diets have the potential to alleviate IBD by modulating the underlying pathogenic mechanisms. Future comprehensive studies are needed to corroborate the potential roles of functional foods and diets in the prevention and control of IBD.

Heme Oxygenase-1 Induction and Anti-inflammatory Actions of Atractylodes macrocephala and Taraxacum herba Extracts Prevented Colitis and Was More Effective than Sulfasalazine in Preventing Relapse

Background/Aims

In inflammatory bowel disease (IBD), repeated bouts of remission and relapse occur in patients and can impose a risk of colitis-associated cancer. We hypothesized that plant extracts of Atractylodes macrocephala (AM) or Taraxacum herba (TH) may be better than sulfasalazine for treating this disease because these extracts can promote additional regeneration.

Methods

Murine intestinal epithelial IEC-6 cells were pretreated with AM or TH before a lipopolysaccharide (LPS)-induced challenge. Acute colitis was induced with 7 days of dextran sulfate sodium (DSS) in male C57BL/6 mice, and extracts of AM and TH were administered for 2 weeks before DSS administration.

Results

In vitro studies demonstrated that AM or TH treatment reduced LPS-induced COX-2 and tumor necrosis factor-α mRNA levels but increased heme oxygenase-1 (HO-1). Oral preadministration of AM and TH rescued mice from DSS-induced colitis by inhibiting inflammatory mediators via inactivated extracellular signal regulated kinase and repressed nuclear factor κB and signal transducer and activator of transcription 3, but the effect was weaker for sulfasalazine than that for the extracts. Anti-inflammatory activities occurred via the inhibition of macrophage and T lymphocyte infiltrations. Unlike sulfasalazine, which did not induce HO-1, TH extracts afforded significant HO-1 induction.

Conclusions

Because the AM or TH extracts were far superior in preventing DSS-induced colitis than sulfasalazine, AM or TH extracts can be considered natural agents that can prevent IBD relapse.

Polyphenol-rich extract of Ocimum gratissimum leaves ameliorates colitis via attenuating colonic mucosa injury and regulating pro-inflammatory cytokines production and oxidative stress

Colitis is a chronic inflammation and ulcer on the inner lining of the large intestine. For many centuries Ocimum gratissimum (OG) leaves have been used in folk medicine in Nigeria to treat inflammatory bowel diseases, however, to date, the anti-colitis effects of OG have not been scientifically proven. In this study we investigated the effects of polyphenol rich extract of Ocimum gratissimum (PREOG) leaf on colonic mucosa injury in colitis, its mechanisms, initial administration time and dosage. Dextran sodium sulfate (DSS)-induced rat colitis models was used. PREOG administration was initiated at 3 and 7 d after the model was established at doses of 200, 400 and 800 mg/kg for 7 d. 5-aminosalicylic acid (5-ASA) was used as a reference drug. The disease activity index (DAI), vascular permeability, markers of oxidative stress, granulocyte infiltration, inflammation and histopathological alteration were evaluated. Obvious colonic inflammation and mucosa injuries were observed in DSS-induced colitis groups. PREOG administration promoted repair of colonic mucosa injuries, attenuated inflammation, and decreased DAI scores in rats with colitis. PREOG also decreased the plasma concentrations of Interleukin-(IL)-6 and tumor necrosis factor (TNF)-α, and concentrations of myeloperoxidase, nitric oxide, cyclooxygenase-2 and malondialdehyde in the colon, and increased the plasma concentrations of IL-4 and IL-10 as well as the concentration of superoxide dismutase, catalase and reduced glutathione in the colon. The efficacy of PREOG was dosage dependent. In conclusion, OG repairs colonic mucosa injury in experimental colitis through its ant-inflammatory and ant-oxidant. Its efficacy related to initial administration time and dose.

A medicinal plant compound, capnoidine, prevents the onset of inflammation in a mouse model of colitis

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional uses of Corydalis dubia, Ajania nubigena and Pleurospermum amabile in the Bhutanese traditional medicine for treating disorders related to inflammatory conditions and the in vitro anti-inflammatory activity of their crude extracts inspired the isolation and the investigation of anticolitic properties of four pure compounds.

MATERIALS AND METHODS

Three medicinal plants were collected from Himalayan Mountains of Bhutan. Capnoidine and scoulerine were isolated from C. dubia, linalool oxide acetate from A. nubigena and isomyristicin from P. amabile using natural product isolation protocols. Four compounds were investigated for their anti-inflammatory activities against IBD-colitis using chemically induced (TNBS) mice model of colitis. Capnoidine conferred the best preliminary protection against TNBS-induced colitis in mice and we have conducted in-depth pharmacological investigation of this compound including clinical symptoms, pathological signs, cytokine profiles, histological structure and inflammasomes using relevant bioassay protocols.

RESULTS

Capnoidine-treated mice had significantly: a) improved clinical symptoms (body weight loss, mobility, piloerection and faecal consistency); b) reduced colon pathology (adhesion, oedema, ulceration, and colon length); c) altered inflammatory cytokines profiles within the colons; d) reduced levels of p-IκB-α (Ser32) and p-NF-κB p65 (Ser536) and e) reduced histological inflammation in the colon when compared with mice administered TNBS only.

CONCLUSION

Capnoidine presents as a potential new anti-inflammatory drug lead candidate for diseases where current standard-of-care often fails and is associated with major side effects. It also validates the traditional uses of C. dubia against inflammatory conditions and underlines the value of pursuing bioactive compounds derived from traditionally used ethnobotanical medicines.