Anti-inflammatory natural products modulate interleukins and their related signaling markers in inflammatory bowel disease: A systematic review

This review aims to identify in vivo studies investigating the potential of plant substances and their natural molecules in managing inflammatory bowel disease (IBD). Specifically, the objective is to examine the impact of these substances on interleukins and other key inflammatory signaling markers. Relevant articles published up to December 2022 were identified through a search of the PubMed, Scopus, Web of Science, and Embase databases. The search used keywords including "inflammatory bowel disease", "medicinal plants", "natural molecules", "anti-inflammatory", and "ulcerative colitis", and identified 1,878 potentially relevant articles, of which 89 were included in this review after completion of the selection process. This study provides preclinical data on natural products (NPs) that can potentially treat IBD, including ulcerative colitis. The main actions of these NPs relate to their effects on nuclear factor kappa B (NF-κB), the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway, the regulation of T helper 17/regulatory T cells balance, and oxidative stress. The ability of these NPs to inhibit intestinal inflammation appears to be dependent on lowering levels of the pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, and IL-17, via the Jun N-terminal kinase (JNK)1, NF-κβ-p65, and STAT3 pathways. In addition, NPs were shown to reduce oxidative stress and the severity of ulcerative colitis, as well as increase the activity of antioxidant enzymes. These actions suggest that NPs represent a promising treatment for IBD, and potentially have greater efficacy and safety than current treatments.

Astragalus membranaceus as a Drug Candidate for Inflammatory Bowel Disease: The Preclinical Evidence

Inflammatory bowel disease (IBD) is a group of chronic inflammatory disorders that include Crohn's disease (CD) and ulcerative colitis (UC). Today, IBD has no successful treatment. As a result, it is of paramount importance to develop novel therapeutic agents for IBD prevention and treatment. Astragalus membranaceus (AMS) is a traditional Chinese medicine found in the AMS root. Modern pharmacological studies indicate that AMS and its constituents exhibit multiple bioactivities, such as anti-inflammatory, anti-oxidant, immune regulatory, anticancer, hypolipidemic, hypoglycemic, hepatoprotective, expectorant, and diuretic effects. AMS and its active constituents, which have been reported to be effective in IBD treatment, are believed to be viable candidate drugs for IBD treatment. These underlying mechanisms are associated with anti-inflammation, anti-oxidation, immunomodulation, intestinal epithelial repair, gut microbiota homeostasis, and improved energy metabolism. In this review, we summarize the efficacy and underlying mechanisms involved in IBD treatment with AMS and its active constituents in preclinical studies.

Mesenchymal Stem Cells and Begacestat Mitigate Amyloid-β 25-35-Induced Cognitive Decline in Rat Dams and Hippocampal Deteriorations in Offspring

Alzheimer's disease (AD) is the most common cause of age-related neurodegeneration and cognitive decline. AD more commonly occurs in females than in males, so it is necessary to consider new treatments specifically targeting this population. The present study investigated the protective effects of Begacestat (γ-secretase inhibitor-953, GSI-953) and bone marrow-derived mesenchymal stem cells (BM-MSCs) during pregnancy on cognitive impairment in rat dams and neurodegeneration in offspring caused by the intracerebroventricular injection of Aβ 25-35 before pregnancy. The performances of dams injected with amyloid-β 25-35 (Aβ 25-35) during behavioral tests were significantly impaired. The offspring of Aβ 25-35-injected dams treated with BM-MSCs or GSI-953 showed a dramatically reduced number and size of activated microglial cells, enhancement in the processes length, and a decrease in the proinflammatory cytokine levels. Additionally, BM-MSC or GSI-953 therapy reduced Aβ 25-35-induced increases in tau phosphorylation and amyloid precursor protein levels in the neonates' hippocampus and elevated the lower levels of glycogen synthase kinase-3 and brain-derived neurotrophic factor; moreover, reversed Aβ 25-35-induced alterations in gene expression in the neonatal hippocampus. Finally, the treatments with BM-MSC or GSI-953 are globally beneficial against Aβ 25-35-induced brain alterations, particularly by suppressing neural inflammation, inhibiting microglial cell activation, restoring developmental plasticity, and increasing neurotrophic signaling.

Bone Marrow-Derived Mesenchymal Stem Cells and γ-Secretase Inhibitor Treatments Suppress Amyloid-β25-35-Induced Cognitive Impairment in Rat Dams and Cortical Degeneration in Offspring

Alzheimer's disease (AD) is the most frequent cause of age-related neurodegeneration and ensuing cognitive impairment. Progressive deposition of extracellular amyloid beta (Aβ) aggregates (plaques) and intracellular hyperphosphorylated Tau protein (p-Tau) are the core pathological markers of AD but may precede clinical symptoms by many years, presenting a therapeutic window of opportunity. Females are more frequently afflicted by AD than males, necessitating evaluation of novel treatments for the female population. The current study examined the protective efficacies of intravenous bone marrow-derived mesenchymal stem cells (BM-MSCs) and oral gamma-secretase inhibitor-953 (GSI-953) during pregnancy on cognitive impairment in rat dams and neurodegeneration in offspring induced by intracerebroventricular injection of Aβ25-35 prior to pregnancy. The Aβ25-35 (AD) group exhibited significant (P < 0.001) impairments in the Y-maze and novel object recognition test performance prior to conception. Histological analysis of the offspring cortex revealed substantial dendritic shrinkage and activation of microglial cells, while neurochemical analysis demonstrated significant increases in the proinflammatory cytokine interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). In contrast, BM-MSC or GSI-953 treatment of dams following Aβ25-35 injection significantly (P < 0.001) reduced the number and size of activated microglial cells, markedly increased dendrite length, and reversed proinflammatory cytokine elevations in offspring. Moreover, BM-MSC or GSI-953 treatment reversed the Aβ25-35-induced amyloid precursor protein and p-Tau elevations in the offspring brain; these changes were accompanied by upregulation of the brain-derived neurotrophic factor and downregulation of glycogen synthase kinase-3β in the serum and brain. Treatment with BM-MSCs or GSI-953 also reversed Aβ25-35-induced elevations in different gene expressions in the neonatal cortex. Finally, treatment of dams with BM-MSCs or GSI-953 prevented the Aβ25-35-induced disruption of newborn brain development. Thus, BM-MSC and GSI-953 treatments have broad-spectrum effects against Aβ25-35-induced brain pathology, including the suppression of neural inflammation, restoration of developmental plasticity, and promotion of neurotrophic signaling.

Preventive effect of tilapia skin collagen hydrolysates on ulcerative colitis mice based on metabonomic and 16 S rRNA gene sequencing

BACKGROUND

Tilapia skin collagen hydrolysates (TSCHs) are the product of enzymatic hydrolysis of collagen, which is mainly extracted from tilapia skin. The components of TSCHs have recently been reported to play a preventive role in dextran sulfate sodium (DSS)-induced ulcerative colitis (UC). However, it has not been illustrated whether TSCHs can prevent against DSS-induced UC via the gut microbiota and its derived metabolites.

RESULTS

TSCHs are mainly composed of amino acids, which have similar characteristics to collagen, with most having a molecular weight below 5 kDa. In a mouse model of UC, TSCHs had no toxic effect at a dose of 60 g kg^-1 and could reduce body weight changes, colon length, histopathological changes and score, and the level of the serum inflammatory cytokine interleukin (IL)-6. Concurrently, 16 S rRNA sequencing showed that TSCHs significantly reduced the abundance of Bacteroidetes and Proteobacteria at the phylum level and norank_f__Muribaculaceae and Escherichia-Shigella at the genus level, while they increased the abundance of Firmicutes at the phylum level and Lachnoclostridium, Allobaculum, Enterorhabdus, and unclassified__f__Ruminococcaceae at the genus level. Target metabolomic analysis showed that TSCHs elevated the concentration of total acid, acetic acid, propanoic acid, and butanoic acid, but reduced isovaleric acid concentrations. Moreover, Pearson correlation analysis revealed that Allobaculum, unclassified_Ruminococcaceae, and Enterorhabdus were positively correlated with acetic acid and butyric acid, but not Escherichia-Shigella.

CONCLUSION

These findings suggest that TSCHs can prevent UC by modulating gut microbial and microbiota-derived metabolites. © 2023 Society of Chemical Industry.

AC1Q3QWB inhibits colorectal cancer progression by modulating the immune response and balancing the structure of the intestinal microbiota

AC1Q3QWB enhances CD8 + T cell response and triggers accumulation of Tregs and B cells.

BACKGROUND

Colorectal cancer (CRC) is a common malignancy with high mortality and few effective therapeutic measures. Gut microbiota dysbiosis and chronic inflammation might contribute to the development of CRC. The present study aimed to explore the effect of AC1Q3QWB (AQB) on colon carcinogenesis in vivo.

METHODS

A mouse colon cancer model was constructed by intraperitoneal injection of 10 mg/kg of Azoxymethane (AOM) and 2 % dextran sodium sulfate (DSS) in drinking water. Mice were randomly assigned to four groups: normal control (NC), AOM/DSS (model control, MC), DMSO + AOM/DSS (DMSO), and AQB + AOM/DSS (AQB). Mice in the AQB group were treated with an intraperitoneal injection of AQB (50 mg/kg) after successful modeling. Then, the disease activity index (DAI) of colitis was analyzed. Colon tissues were collected for hematoxylin-eosin, immunohistochemistry, and microscopic and histological evaluation. Stool samples were collected for microbiota analysis by 16S rRNA sequencing. Blood samples were analyzed by flow cytometry to investigate the inflammatory response.

RESULTS

In AOM/DSS-induced CRC mouse model, AQB treatment dramatically reduced the number and size of colon tumors. AQB treatment enhances CD8+⁺T cell response and triggers the accumulation of CD4+⁺CD25+⁺Foxp3+⁺Regulatory T cells (Tregs) and B cells. AQB regulated the structure and composition of the gut microbiota, which decreased the Firmicutes/Bacteroidetes ratio at the phylum level and increased the abundance of probiotics.

CONCLUSIONS

AQB has potent antitumor activity against colorectal cancer in vivo by a mechanism that might involve modulation of the immune system and alteration of the intestinal microbiota.

Antiviral Activities of Ethyl Pheophorbides a and b Isolated from Aster pseudoglehnii against Influenza Viruses

Screening of the antiviral and virucidal activities of ethanol extracts from plants endemic to the Republic of Korea revealed the inhibitory activity of a 70% ethanol extract of the whole plant of A. pseudoglehnii (APE) against influenza virus infection. Two chlorophyll derivatives, ethyl pheophorbides a and b, isolated as active components of APE, exerted virucidal effects with no evident cytotoxicity. These compounds were effective only under conditions of direct incubation with the virus, and exerted no effects on the influenza A virus (IAV) surface glycoproteins hemagglutinin (HA) and neuraminidase (NA). Interestingly, virucidal activities of ethyl pheophorbides a and b were observed against enveloped but not non-enveloped viruses, suggesting that these compounds act by affecting the integrity of the viral membrane and reducing infectivity.

Anti-Colitic Effect of an Exopolysaccharide Fraction from Pediococcus pentosaceus KFT-18 on Dextran Sulfate Sodium-Induced Colitis through Suppression of Inflammatory Mediators

We previously reported the immunostimulatory effect of an exopolysaccharide fraction from Pediococcus pentosaceus KFT18 (PE-EPS), a lactic acid bacterium, in macrophages and primary splenocytes, as well as in cyclophosphamide-induced immunosuppressed mice. In this study, the anti-colitic activity of PE-EPS was investigated in a dextran sulfate sodium (DSS)-induced colitis animal model. PE-EPS relieved DSS-induced colitis symptoms, such as stool blood, decreased colon length, crypt disruption, and mucus layer edema. Regarding the molecular mechanism, PE-EPS reduced the enhanced expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and pro-inflammatory cytokines (TNF-α, IL-6, and IL-1) in the colon tissue of colitis-induced mice. Additionally, PE-EPS protected against DSS-induced phosphorylation of p65 and signal transducer and activator of transcription 1 (STAT1). These findings suggested that the exopolysaccharide fraction from Ped. pentosaceus KFT18 can be used to treat inflammatory bowel disease by alleviating colonic inflammation.

Terazosin Stimulates Pgk1 to Remedy Gastrointestinal Disorders

Gastrointestinal disease is the most common health concern that occurs due to environmental, infectious, immunological, psychological, and genetic stress. Among them, the most frequent diseases are gastric ulcer (GU) and ulcerative colitis (UC). DSS-induced UC and ethanol-stimulated GU models resemble the pathophysiology of human gastrointestinal disease. The current study was designed to explore the anti-oxidation, anti-inflammation, anti-cell death properties of terazosin, an α-adrenergic receptor antagonist, in vivo and in vitro. Our results indicate that terazosin dramatically activates Pgk1, and upregulates glycose metabolism, evidenced by the enhanced ATP production and higher LDH enzymatic activity. Also, terazosin significantly enhances p-AKT expression and inhibits NF-κB p65 activation through abrogating the phosphorylation of IKBα, as well as lowers Caspase-1 and GSDMD expression. The findings in this study demonstrate that terazosin exhibits anti-inflammatory effects by downregulating NF-κB-GSDMD signal pathway, along with enhancing glycolysis for gastrointestinal disease treatment. Meanwhile, we also find terazosin ameliorates ethanol-induced gastric mucosal damage in mice. Collectively, as a clinical drug, terazosin should be translated into therapeutics for gastrointestinal disease soon.

Evaluation of Subchronic Toxicity and Genotoxicity of Ethanolic Extract of Aster glehni Leaves and Stems

Aster glehni, a traditional plant on Ulleung Island in the Republic of Korea, has been recognized for its multiple medicinal properties. However, potential toxicity and safety analyses of A. glehni have not been previously investigated. Therefore, this study aimed to evaluate the safety profile of ethanolic extract of A. glehni leaves and stems (EAG) in terms of genotoxicity and subchronic oral animal toxicity under OECD guidelines and GLP conditions. Toxicological assessments were performed at doses of 1,250, 2,500, and 5,000 mg/kg/day in a 13-week oral repeated-dose toxicity study of EAG in male and female SD rats. In addition, an Ames test, an in vitro mammalian chromosomal aberration test, and a micronucleus test were performed. No toxicological changes in clinical signs, body weights, water and food consumption, urinalysis, hematology, clinical biochemistry, gross findings, and histopathological examinations were observed in subchronic oral animal toxicity. In addition, EAG gave negative results when evaluated using in vitro and in vivo genotoxicity tests. In conclusion, the no-observed-adverse-effect level (NOAEL) of EAG was considered to be 5,000 mg/kg/day, and no target organs were identified in both sexes of rats. EAG was also classified as nonmutagenic and nonclastogenic in genotoxicity testing. Collectively, these results show a lack of general toxicity and genotoxicity for EAG that supports clinical work for development as a herbal medicine.

Protective Effects of Shrimp Peptide on Dextran Sulfate Sodium-Induced Colitis in Mice

Inflammatory bowel disease, an intestinal relapsing inflammatory disease, not only impairs gastrointestinal function but also increases the chances of developing colon cancer. Currently, the effects of shrimp peptide (SP) in mice model of ulcerative colitis (UC) are still unclear. In particular, it is uncertain whether SP affects the gut flora with UC mice. In this study, we investigated the anti-inflammatory effects of SP on a dextran sulfate sodium (DSS)-induced mouse model of UC. Firstly, the molecular weight of SP was mainly distributed in the range of 180-1,000 Da (61.95% proportion), and the amino acid composition showed that SP contained 17 amino acids, of which, the essential amino acids accounted for 54.50%. In vivo, oral SP significantly attenuated the severity of colitis, such as diarrhea, weight loss, and rectal bleeding. Furthermore, treatment with SP remarkably ameliorated intestinal barrier integrity, thus lowering the levels of the inflammatory cytokines and ameliorating antioxidant indices and intestinal injury indicators in the serum and colon. Lastly, the cecal contents were used to sequence and analyze the 16S rRNA genes of bacteria. Results suggested that treatment with SP could restore the balance of intestinal flora in modeled mice by regulating the abundance of pathogenic and beneficial bacteria. Furthermore, SP could significantly improve intestinal flora dysfunction in mice with UC. In summary, our findings show that SP has a prophylactic and therapeutic effect in UC in vivo, thereby highlighting its broad medicinal applications.

A review on the molecular mechanisms, the therapeutic treatment including the potential of herbs and natural products, and target prediction of obesity-associated colorectal cancer

Colorectal cancer (CRC) is the third leading cause of cancer death worldwide. Obesity has been proven to be closely related to colorectal carcinogenesis. This review summarized the potential underlying mechanisms linking obesity to CRC in different aspects, including energy metabolism, inflammation, activities of adipokines and hormones. Furthermore, the potential therapeutic targets of obesity-associated CRC were predicted using network-based target analysis, with total predicted pathways not only containing previously reported pathways, but also putative signaling pathways pending for investigation. In addition, the current conventional therapeutic treatment options, plus the potential use of herbs and natural products in the management of obesity-associated CRC were also discussed. Taken together, the aim of this review article is to provide strong theoretical basis for future drug development, particularly herbs and natural products, in obesity-associated CRC.

Extracts of Waste from Poplar Wood Processing Alleviate Experimental Dextran Sulfate-Induced Colitis by Ameliorating Oxidative Stress, Inhibiting the Th1/Th17 Response and Inducing Apoptosis in Inflammatory Lymphocytes

As a fast-growing tree, poplar is widely planted and typically used for wood processing in China. During poplar wood processing, a large amount of poplar sawdust (PS) and poplar leaves (PL) are produced and abandoned. To make full use of poplar resources and clarify the use of poplar as a feed additive, the active ingredients in PS and PL were extracted and isolated, and the anti-inflammatory effects of the extracts on mice with dextran sulfate sodium (DSS)-induced colitis were investigated. In vitro anti-inflammatory experiments showed that the ethyl acetate extract of PS and PL (PSE and PLE, respectively) could significantly inhibit the proliferation of concanavalin A (Con A)-activated lymphocytes. Salicortin, tremulacin and salireposide were identified in both PSE and PLE. Oral administration of PSE and PLE rescued DSS-induced colonic shortening, repaired tissue damage, and decreased the disease activity index (DAI). The antioxidant capacity, including the increased activities of glutathione peroxidase (GSH-Px), total superoxide dismutase (T-SOD and catalase (CAT) and decreased activity of myeloperoxidase (MPO), in the colons of mice with colitis was enhanced through the activation of ERK after treatment with PSE and PLE. The ratio of Th1 to Th17 cells, which can lead to inflammation in the spleen, was significantly decreased by the administration of PSE and PLE, while the phosphorylation of related transcription factors (p65, STAT1, and STAT3) was inhibited. Furthermore, PSE and PLE could induce apoptosis in Con A-activated lymphocytes, which may be associated with the increase in p-TBK1, as the molecular docking results also indicated that salireposide in PSE and PLE could interact with the TBK1 protein. Overall, our study provides a promising feed additive for improving intestinal inflammation in animals and a method for the full utilization of poplar resources.

The preventive effect and underlying mechanism of Rhus chinensis Mill. fruits on dextran sulphate sodium-induced ulcerative colitis in mice

The purpose of this research was to explore the preventive effect of an 80% ethanol extract of Rhus chinensis Mill. fruits on dextran sulfate sodium (DSS)-induced colitis in mice and to elucidate the underlying molecular mechanisms of this effect. The results indicated that the extract, especially when administered at a high dose, could dramatically decrease the disease activity index, maintain normal spleen conditions, and improve colonic histopathology and length in the DSS-induced mice. In addition, extract administration could significantly suppress the levels of malondialdehyde, myeloperoxidase, tumor necrosis factor-α, interleukin-1β, and interleukin-6 and enhance superoxide dismutase and glutathione levels. The extract obviously protected intestinal barrier integrity by improving Occludin, ZO-1 and Claudin-1 expression levels. Western blot and immunohistochemistry analyses further indicated that the preventive effect of the phenol-rich extract on DSS-induced colitis might be achieved through the up-regulation of the expression of several pivotal oxidative stress-associated proteins, namely Nrf2, NQO1 and HO-1, and the down-regulation of the expression of several pivotal inflammation-associated proteins, namely p-NF-κB, p-IκB, COX-2, iNOS, p-P38, p-Erk1/2, and p-JNK. Therefore, R. chinensis fruits extract possesses the capability to prevent DSS-induced ulcerative colitis in mice and could be utilized as a natural substance in the exploitation of functional foods as an adjuvant dietary therapy for preventing and/or alleviating inflammatory bowel disease.

Morchella importuna Flavones Improve Intestinal Integrity in Dextran Sulfate Sodium-Challenged Mice

Morchella importuna, as an edible fungus, has various health benefits. However, the effects of M. importuna on intestinal health are rarely investigated. Hence, this study aims to ascertain the influences of flavones from the fruiting bodies of M. importuna (hereinafter abbreviated as MIF) on dextran sulfate sodium (DSS)-induced damage to intestinal epithelial barrier in C57BL/6J mice. In this (14-day) study, 144 C57BL/6J mice were divided into four groups: (1) Control; (2) DSS treatment; (3) DSS treatment + 100 mg/kg MIF (LMIF); (4) DSS treatment + 200 mg/kg MIF (HMIF). On days 8-14, mice in the challenged groups were challenged with 3.5% DSS, while the control group received an equal volume of normal saline. Then, serum and intestinal samples were obtained from all mice. The results showed that MIF ingestion enhanced intestinal integrity in DSS-challenged mice, as evinced by the elevated (p < 0.05) abundances of occludin, claudin-1, and zonula occludens-1 proteins. Meanwhile, MIF ingestion reduced (p < 0.05) the colonic interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) concentrations and increased the superoxide dismutase and catalase activities and Shannon and Simpson indices in DSS-challenged mice. Moreover, MIF ingestion reduced (p < 0.05) the abundance of phospho-nuclear factor (NF)-κB and increased the abundance of phospho-Nrf2 in DSS-challenged mice. Taken together, MIF protects against intestinal barrier injury in C57BL/6J mice via a mechanism that involves inhibiting NF-κB activation and promoting Nrf2 activation, as well as regulating intestinal microbiota.

A Novel Nanomedicine Ameliorates Acute Inflammatory Bowel Disease by Regulating Macrophages and T-Cells

Ramulus mori polysaccharide (RMP), one of the most important active components of R. mori, has been attracting increasing interest because of its potent bioactive properties, including anti-inflammatory, antitumor, and antidiabetic effects. Despite the great therapeutic potential of RMP, its inherent properties of low bioavailability and brief biological half-life have limited its applications to the clinic. Thus, RMP was packaged by poly(lactic-co-glycolic acid) (PLGA) nanoparticles to develop a novel anti-inflammatory nanomedicine (PLGA-RMP) in this study. The nanoparticles were synthesized via a double-emulsion solvent evaporation technique, and the average diameter of PLGA-RMP was about 202 nm. PLGA-RMP nanoparticles reduced the expression of inflammatory cytokines while promoting the production of IL-10, and boosted the phenotypic shift in macrophages in vitro. Furthermore, lipopolysaccharide (LPS)-induced inflammatory bowel disease (IBD) in mouse was used to examine the anti-inflammatory effect of PLGA-RMP in vivo. Oral administration of PLGA-RMP in LPS-induced IBD mice substantially mitigated the intestinal inflammation compared to treatment with LPS alone, as evidenced by attenuation of disease activity index scores and inflammatory damage in the intestine. Meanwhile, PLGA-RMP suppressed the expression and secretion of specific inflammatory cytokines including TNF-α, IL-6, IL-1β, and PGE2 in the inflamed intestine while inhibiting the activation of CD3⁺CD8⁺ T-cells and increasing the number of activated T_regs in the intestine. These results indicated that PLGA-RMP deserves further consideration as a potential therapeutic nanomedicine to treat various inflammatory diseases, including IBD.

Saccharomyces boulardii Ameliorates Dextran Sulfate Sodium-Induced Ulcerative Colitis in Mice by Regulating NF-κB and Nrf2 Signaling Pathways

Saccharomyces boulardii (S. boulardii) is a probiotic yeast that is widely used to treat gastrointestinal disorders. The present study is aimed to explore the therapeutic effects of S. boulardii on dextran sulfate sodium- (DSS-) induced murine ulcerative colitis (UC) and illustrate the mechanisms of action. C57BL/6 mice were administered S. boulardii (10⁵ and 10⁷ CFU/ml, p.o.) for 3 weeks and then given DSS [2.5% (w/v)] for one week. Administration of S. boulardii prevented DSS-induced reduction in body weight, diarrhea, bloody feces, decreased colon length, and loss of histological structure. Moreover, S. boulardii protected the intestinal barrier by increasing the levels of tight junction proteins zona occludens-1 and Occludin and exerted immunomodulatory effects in DSS-induced mice. Furthermore, S. boulardii suppressed the colonic inflammation by reducing the levels of Interleukin-1β, Interleukin-6, and Tumor necrosis factor alpha and restored myeloperoxidase activity in mice exposed to DSS. S. boulardii also mitigated colonic oxidative damage by increasing the levels of antioxidant enzymes (superoxide dismutase, catalase, and heme oxygenase 1) and glutathione and decreasing malondialdehyde accumulation. Further studies identified that S. boulardii suppressed the nuclear translocation of nuclear factor kappa B (NF-κB) p65 subunit by decreasing IκKα/β levels, while promoted the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) in DSS-exposed mice. Collectively, S. boulardii possessed an appreciable therapeutic effect against the experimental mice model of UC. The protective mechanism of S. boulardii may involve inhibition of NF-κB-mediated proinflammatory signaling and activation of Nrf2-modulated antioxidant defense in addition to intestinal barrier protective and immunomodulatory effects.

Efficient Stool Collection Methods for Evaluating the Diarrhea Score in Mouse Diarrhea Models

BACKGROUND/AIM

The mouse diarrhea score is usually determined by evaluating stool consistency and shape. Thus, defecated stools should be collected without damage or contamination. The study aimed to develop improved mouse stool collection methods and diarrhea-scoring criteria.

MATERIALS AND METHODS

We developed improved stool collection methods (paper towel methods) and compared them with previously used ones (stool collection using regular cages containing bedding chips or filter paper and metabolic cages).

RESULTS

Compared to previously used methods, paper towel methods collected stools without bedding chips-induced contamination, mouse body/foot-induced damage, or sampling errors. When using paper towel methods, wet stools create water marks (diarrhea marks) on paper towels with strong water absorption capacity, by which diarrheal severity can be analyzed semi-quantitatively. To improve the objectivity in determining diarrhea scores, practical diarrhea-scoring criteria were also proposed.

CONCLUSION

These results would be helpful to researchers facing difficulties in evaluating the mouse diarrhea score.

The Inhibitory Effect of Artesunate on Excessive Endoplasmic Reticulum Stress Alleviates Experimental Colitis in Mice

Endoplasmic reticulum (ER) stress may contribute to the pathogenesis and perpetuation of ulcerative colitis (UC). Previous studies have shown artesuante (ARS) has the protective effect on experimental UC. Therefore, it can be assumed that ARS can regulate ER stress and its related reactions. Dextran sulfate sodium (DSS) induced UC model in mice was used to testify this hypothesis. The results clearly showed that DSS exposure caused excessive ER stress evidenced by a markedly increase of GRP78 and CHOP expression, and then activated the ER stress sensors PERK, IRE1, ATF6 and their respective signaling pathways, followed by upregulated caspases12 and lowered Bcl-2/Bax ratio. However, ARS treatment significantly inhibited the occurrence of ER stress via preventing the activation of PERK-eIF2α-ATF4-CHOP and IRE1α-XBP1 signaling pathways, concurrently ER-stress-associated apoptosis in colon tissues. Moreover, ARS treatment remarkably inhibited the activation of NF-κB and the expression levels of pro-inflammatory cytokines, improved the clinical and histopathological alterations as well as maintained the expression of claudin-1 and Muc2 in mucosal layer of colon. Notably, the classic ER stress inhibitor 4-phenyhlbutyric acid enhanced the beneficial effects of ARS; in contrast, the ER stress inducer 2-deoxy-d-glucose substantially abrogated the above-mentioned effects, uncovering the involvement of ER stress in the response. These findings indicated the protection of ARS on UC is associated with its suppressing excessive ER stress mediated intestinal barrier damage and inflammatory response. This study provides a novel aspect to understand the mechanism of ARS against UC.

Longan pulp polysaccharide protects against cyclophosphamide-induced immunosuppression in mice by promoting intestinal secretory IgA synthesis

This study aimed to explore the effect of longan pulp polysaccharide (LP) on the systemic immunity and intestinal mucosal immunity of immunosuppressive mice. The synthesis process and secretion of intestinal secretory IgA (SIgA) were investigated. Results showed that LP increased the thymus index, spleen index, and serum IgA level in cyclophosphamide (CTX)-treated mice. SIgA secretion in the intestinal lumen was increased by LP as well. The underlying mechanism comes down to the facts as follow: LP increased intestinal cytokines expression and TGFβRII that is associated with pathways of IgA class switch recombination (CSR). By improving protein expression of mucosal addressin cell-adhesion molecule-1 (MAdCAM-1) and integrin α4β7, LP was beneficial to gut homing of IgA+ plasma cells. LP increased IgA, polymeric immunoglobulin receptor (pIgR), and secretory component (SC) to fortify the SIgA secretion. This study suggested that moderate consumption of LP is helpful for improving systemic immunity and intestinal mucosal immunity via promotion of intestinal SIgA to strengthen the mucosal barrier.

Exploring the Potential Mechanism of Guchang Zhixie Wan for Treating Ulcerative Colitis by Comprehensive Network Pharmacological Approaches and Molecular Docking Validation as Well as Cell Experiments

Guchang Zhixie Wan (GZW) is a commonly used Chinese medicine for the treatment of ulcerative colitis (UC). This research explored the potential pharmacological mechanism of GZW in UC. The active ingredients, potential targets, and UC-related genes of GZW were retrieved from public databases. The pharmacological mechanisms including key components, potential targets and signal pathways were determined through bioinformatics analysis. The results of this study were verified through virtual molecular docking and cell experiments. Network analysis revealed that 26 active GZW compounds and 148 potential GZW target proteins were associated with UC. Quercetin, kaempferol and β-sitosterol were identified as the core active ingredients of GZW. IFNG, IL-1A, IL-1B, JUN, RELA, and STAT1 were indicated as key targets of GZW. These key targets have a strong affinity for quercetin, kaempferol, and β-sitosterol. GO and KEGG enrichment analysis showed that GZW target proteins are highly enriched in inflammatory, immune, and oxidative stress-related pathways. This study confirmed the therapeutic effect and revealed potential molecular mechanism of GZW on UC. And the protective effects of GZW on inflammatory bowel disease pathway were also revealed through STAT3/NF-κB/IL-6 pathway. The findings of this study enhanced our understanding of GZW in the treatment of UC and provided a feasible method for discovering potential drugs from traditional Chinese medicine formulations.

Polyphenol Extract of Moringa Oleifera Leaves Alleviates Colonic Inflammation in Dextran Sulfate Sodium-Treated Mice

Moringa oleifera Lam. is an essential herb used for the treatment of inflammation, diabetes, high blood pressure, and other diseases. In this study, phenolic extracts of M. oleifera leaves were obtained and analyzed. The results showed that the main identifiable phenols were astragalin, chlorogenic acid, isoquercitrin, kaempferitrin, luteolin, quercetin, and rutin. The effects of M. oleifera polyphenol extract (MOPE) on experimental colitis induced by 3% dextran sulfate sodium (DSS) were investigated. The results showed that oral administration of MOPE significantly alleviated the symptoms of DSS-induced colitis. MOPE significantly reduced weight loss, the disease activity index, colon shortening, and mucosal damage. In addition, MOPE attenuated the infiltration of CD3⁺ T cells, CD177⁺ neutrophils, and F4/80⁺ macrophages and significantly inhibited the secretion of IL-6 and TNF-α. After the MOPE administration, the expression of proteins associated with the NF-κB signaling pathway changed. Specifically, compared with that of the DSS group, the protein expression of NF-κB p65 and p-IκBα was downregulated, and the expression of IκBα was upregulated. This study revealed the anti-inflammatory effects and mechanisms of MOPE in the colon, indicating its potential use in preventing inflammation-driven diseases.

Improving silymarin oral bioavailability using silica-installed redox nanoparticle to suppress inflammatory bowel disease

Chronic inflammatory diseases such as inflammatory bowel diseases (IBD), which are strongly related to the overproduction of reactive oxygen species (ROS), have become more threatening to health. Silymarin is an active compound with the effect of expressing anti-inflammatory activity; however, it exhibits poor bioavailability due to the rapid metabolism and secretion, low permeability across the intestinal epithelial cells, and poor water solubility. In this study, we developed silica-containing redox nanoparticles (siRNP) with 50-60 nm in diameter to improve the bioavailability of silymarin by improving its uptake into the bloodstream and delivery to the targeted tissues of the colon. Silymarin-loaded siRNP (SM@siRNP) significantly increased the antioxidant capacity and anti-inflammatory efficacy in vitro by scavenging 2,2-diphenyl-1-picrylhydrazyl free radical and suppressing nitric oxide and pro-inflammatory cytokines as compared to the other treatments such as free silymarin, siRNP, and silymarin-loaded si-nRNP (the control nanoparticle without ROS scavenging property). Orally administered SM@siRNP significantly improved the bioavailability of silymarin and its retention in the colonic mucosa. The anti-inflammatory effects of SM@siRNP were also investigated in dextran sodium sulfate (DSS)-induced colitis in mice and it was observed that SM@siRNP treatment significantly improved the damage in the colonic mucosa of DSS colitis mice as compared to the other treatments. The results in this study indicate that SM@siRNP is a promising nanomedicine for enhancing the anti-inflammatory activity of silymarin and has a high potential for the treatment of IBD.

Guchang Zhixie Wan protects mice against dextran sulfate sodium-induced colitis through modulating the gut microbiota in colon

ETHNOPHARMACOLOGICAL RELEVANCE

Guchang Zhixie Wan (GC) is a traditional Chinese patent medicine used in the treatment of colitis in clinical trials. Though the notable effect of GC on colitis, the concrete mechanism of GC remain elusive. Emerging evidence showed that the imbalances of inflammatory cytokines and gut microbiota were both closely related to the initiation and progression of colitis.

AIM OF THE STUDY

To elucidate the relationship between the protective effects of GC on colitis and gut microbiota.

MATERIALS AND METHODS

Male Kunming (KM) mice were enrolled in our work to establish colitis model induced by dextran sulfate sodium (DSS). The colitis mice were randomly divided into different groups and treated orally with 125 mg/kg of sulfasalazine (positive control) and 25, 50, 100 mg/kg of GC for 7 days, respectively. Inflammation cytokines of IL-1β, IL-4, IL-6, IL-8, IL-11, IL-12 and TNF-α were detected by ELISA analysis and the histological changes were detected by H&E staining. Gut microbiota diversity was analyzed by 16S rDNA sequencing. Metagenomes analysis were also conducted to reflect the protective effects of GC on colitis.

RESULTS

The results of CAS (Clinical Activity Score) confirmed the protective effects of GC on colitis. After administration of GC, the levels of pro-inflammatory cytokines IL-1β, IL-6, IL-8, IL-11, IL-12 and TNF-α were all decreased while the anti-inflammatory cytokines IL-4 was slightly increased, indicating that GC could down regulate pro-inflammatory cytokines. H&E staining revealed that GC could improve the histopathological structure of the colon tissue. The results of 16S rDNA sequences analysis showed that GC could decrease the relative abundance of Turicibacter and increase the relative abundance of Ruminococcaceae_UCG-005.

CONCLUSION

GC greatly improve the health condition of colitis mice induced by DSS through improving the imbalances of inflammatory cytokines and gut microbiota.

The amelioration of ulcerative colitis induced by Dinitrobenzenesulfonic acid with Radix Hedysari

Ulcerative colitis (UC) is a chronic inflammatory disease with an unknown precise etiology. This study proves that Radix Hedysari (RH) ameliorates UC. Four RH extracts were used to ameliorate UC induced by 2,4-Dinitrobenzenesulfonic acid by 7 days intervention in agreement to preliminary studies. Compared to treatment with RH extracts, the RH ethanol extract (EE) was found to be more effective in ameliorating UC. With EE, the DAI were significantly decreased. Macroscopic and histopathological assessments suggest that the colon mucosa was repaired, the organizational structure of the colon had been rebuilt. The levels of MPO, TNF-α, IL-1β, and MDA were significantly decreased (p < .01), the levels of T-SOD and CAT were significantly increased (p < .01). Moreover, the compounds in EE were analyzed by HPLC. The results show that EE can ameliorate UC, and its anti-inflammatory capability probably plays an important role. RH can act as a functional food and ameliorate UC. PRACTICAL APPLICATIONS: In this work, the ameliorative effect of RH on UC was evaluated from multiple angles. There are two practical applications of this work. On the one hand, a new approach to ameliorating UC is provided by this work. In addition, UC patients have a new option for improving their symptoms. On the other hand, this work also provides information on how best to process RH for therapeutic use. In addition, we can utilize some compounds of RH that were once considered useless and reduce the waste of natural resources.

Astragalus polysaccharides alleviates LPS-induced inflammation via the NF-κB/MAPK signaling pathway

Early weaning usually causes intestinal disorders, enteritis, and diarrhea in young animals and human infants. Astragalus polysaccharides (APS) possesses anti-inflammatory activity. To study the anti-inflammatory mechanisms of APS and its potential effects on intestinal health, we performed an RNA sequencing (RNA-seq) study in lipopolysaccharide (LPS)-stimulated porcine intestinal epithelial cells (IPEC-J2) in vitro. In addition, LPS-stimulated BALB/c mice were used to study the effects of APS on intestinal inflammation in vivo. The results from the RNA-seq analysis show that there were 107, 756, and 5 differentially expressed genes in the control versus LPS, LPS versus LPS+APS, and control versus LPS+APS comparison groups, respectively. The results of Kyoto Encyclopedia of Genes and Genomes enrichment analysis indicated that the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways play significant roles in the regulation of inflammatory factors and chemokine expression by APS. Further verification of the above two pathways by using western blot and immunofluorescence analysis revealed that the gene expression levels of the phosphorylated p38 MAPK, ERK1/2, and NF-κB p65 were inhibited by APS, while the expression of IκB-α protein was significantly increased (p < .05), indicating that APS inhibits the production of inflammatory factors and chemokines by the inhibition of activation of the MAPK and NF-κB inflammatory pathways induced by LPS stimulation. Animal experiments further demonstrated that prefeeding APS in BALB/c mice can alleviate the expression of the jejunal inflammatory factors interleukin 6 (IL-6), IL-Iβ, and tumor necrosis factor-α induced by LPS stimulation and improve jejunal villus morphology.

High-Fat Diet Propelled AOM/DSS-Induced Colitis-Associated Colon Cancer Alleviated by Administration of Aster glehni via STAT3 Signaling Pathway

Many epidemiological observational studies suggest that a high-fat diet (HFD) accelerates the risk of colorectal cancer (CRC). Inflammation can play a key role in the relationship between colon cancer and HFD. Although reported by several studies, controlled experimental studies have not explored this relationship. We established an HFD-fed colitis-associated colon cancer (CAC) mice model and evaluated the anti-tumorigenic effects of AG on HFD-propelled CAC along with its mechanism of action. Previously, we found that Aster glehni (AG) exerts chemopreventive effects on azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced CAC in a mice model, and has anti-adipogenic effects in a HFD-induced obesity mice model. In the HFD-propelled CAC mice model, AG significantly reduced cancer-related death, prevented body weight loss, and alleviated splenic enlargement. Additionally, AG prevented colon shortening and reduced the number of colorectal polyps. Histological studies demonstrated the up-regulation of inflammation, hyperplasia, and neoplasia in HFD-propelled CAC mice, whereas AG suppressed colonic disease progression and tumorigenesis. Furthermore, AG significantly inhibited the signal transducer and activator of transcription 3 (STAT3) signaling pathway and attenuated the protein expression of the STAT3 target gene, which mediates transcription factor-dependent tumor cell proliferation. These results indicate that AG abrogates inflammation-induced tumor progression in HFD-propelled CAC mice by inhibiting STAT3 activation.

The natural flavonoid galangin ameliorates dextran sulphate sodium-induced ulcerative colitis in mice: Effect on Toll-like receptor 4, inflammation and oxidative stress

This study was carried out to investigate the potential therapeutic effect of galangin, a promising active principle of honeybee propolis, in dextran sulphate sodium (DSS)-induced colitis in mice. We explored the possible underlying mechanisms for galangin action and the therapeutic benefit of adding galangin to the standard therapy sulphasalazine. A galangin dose of 40 mg/kg was selected based on a preliminary dose-selection study for investigation in a 4-week cyclical model of DSS-induced colitis. Mice received 3% DSS in their drinking water during the first and third weeks and were administered the treatments (40 mg/kg galangin, 100 mg/kg sulphasalazine and a combination of 20 mg/kg galangin and 50 mg/kg sulphasalazine) daily starting from the second week. Galangin significantly ameliorated DSS-induced histopathological alterations and tissue injury, down-regulated Toll-like receptor 4 expression, suppressed NF-κB p65 activation, lowered inflammatory cytokine levels and demonstrated antioxidant effects. The combination of galangin and sulphasalazine at half doses yielded comparable results to either drug alone at full dose. This study highlights galangin as a promising therapy for colitis management.

Aster glehni Extract Ameliorates Scopolamine-Induced Cognitive Impairment in Mice

The leaves of Aster glehni Fr. Schm. (Asteraceae) have been used to treat insomnia in Korea. Insomnia is a common adverse effect of therapeutic agents for Alzheimer's disease (AD), and the control of sleep disturbance may prevent dementia. We hypothesized that the leaves of A. glehni can attenuate cognitive dysfunctions observed in AD. We observed the ameliorating effects of the ethanolic extract of leaves of A. glehni (AG-D) on memory dysfunction through the Morris water maze test, the passive avoidance test, and the Y-maze test. We performed acetylcholinesterase (AChE) activity assay and Western blotting to determine the mechanism of action of AG-D. AG-D significantly attenuated memory dysfunction observed in the above behavior studies and inhibited the activity of AChE. AG-D also increased the levels of phosphorylation extracellular signal-regulated kinase (ERK), cAMP response element-binding protein (CREB), phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), and glycogen synthase kinase 3β (GSK-3β) and the expression levels of brain-derived neurotrophic factor (BDNF) in the hippocampi. These results suggest that AG-D ameliorates memory impairments by AChE inhibition and activation of ERK-CREB-BDNF and PI3K-Akt-GSK-3β signaling pathways. Taken together, this study suggests that AG-D could be used as a potential treatment for cognitive dysfunction.

Anti-inflammatory effects of Vicenin-2 on dextran sulfate sodium-induced colitis in mice

The objective of the present work was to evaluate the anti-inflammatory effects of Vicenin-2 on dextran sulfate sodium (DSS)-induced colitis model. Colitis was induced in C57BL/6J mice by administration of 2% DSS in drinking water for 7 days. In addition to DSS, Vicenin-2 (50 mg kg^-1 /day^-1 ) was administrated orally to the test group. The ulceration extent and severity were assessed macroscopically, histopathologically, and by disease activity index. The Vicenin-2 treated group showed significant differences in physiological parameters including bodyweight, colon weight, and colon length, compared to DSS-induced colitis group. In addition, Vicenin-2 treatment effectively reduced stool consistency and bleeding scores. Myeloperoxidase (MPO) activity, expressions of pro-inflammatory cytokines, and specific key inflammatory markers (iNOS and COX-2) significantly increased in DSS-induced colitis colon tissues. However, administration of Vicenin-2 effectively reduced the MPO activity, attenuated the expression of pro-inflammatory cytokines and key inflammatory markers, in DSS-induced colitis mice. These results were comparable with sulfasalazine, an anti-inflammatory drug used routinely for ulcerative colitis (UC). These findings suggest that Vicenin-2 effectively suppresses DSS-induced colitis by attenuating expressions of key inflammatory mediators and found to be an attractive therapeutic drug for treating UC.

Screening for active constituents in Turkish galls against ulcerative colitis by mass spectrometry guided preparative chromatography strategy: in silico, in vitro and in vivo study

Turkish galls have been reported to exhibit remedial effects in ulcerative colitis (UC). However, the active constituents of Turkish galls for the treatment of UC remain unclear. The objective of this study was to screen for anti-inflammatory active constituents and clarify their associated molecular mechanisms. Therefore, systems pharmacology was developed to predict the relationship between constituents and the corresponding targets as well as pathways. In addition, mass spectrometry-guided preparative chromatography technique was used for preparing constituents to evaluate the anti-inflammatory activities and the therapeutic efficacy against UC. In silico, active constituents exhibited a remedial effect on UC possibly by regulating multiple pathways and attacking multiple targets, of which those involved mainly in the NF-κB pathway were selected for verification. In vitro, 5 categories of constituents were screened as active constituents by comparing the cytotoxicity and detecting the level of the pro-inflammatory factors of 9 category constituents. In vivo, dextran sulfate sodium (DSS)-induced UC was significantly ameliorated in active constituents-fed mice. The results indicated that the active fraction comprising methyl gallate, digallic acid, di-O-galloyl-β-d-glucose, and tri-O-galloyl-β-d-glucose primarily contributed to the treatment of UC. Moreover, active fraction could also inhibit the phosphorylation level of IKKβ, thus inhibiting the downstream NF-κB signaling pathway. The approach developed in this study not only clarifies the anti-inflammation effect of Turkish galls but also provides a beneficial reference for the discovery of the base material and functional mechanism of this herbal medicine.

CZ2HF mitigates β-amyloid 25-35 fragment-induced learning and memory impairment through inhibition of neuroinflammation and apoptosis in rats

Cu‑zhi‑2‑hao‑fang (CZ2HF), a traditional Chinese medicine, has been used clinically for the treatment of amnesia. However, whether CZ2HF is capable of alleviating learning and memory impairment in Alzheimer's disease (AD) remains to be elucidated. The present study was designed to explore the effect and mechanism of CZ2HF on β‑amyloid 25‑35 (Aβ25‑35)‑induced impairment in the learning and memory of rats. Morris water maze test was used to determine spatial learning and memory ability in Aβ25‑35‑induced AD rats and hippocampal neuronal damage and apoptosis were observed using hematoxylin and eosin staining, Nissl staining and terminal deoxynucleotidyltransferase‑mediated dUTP nick‑end labeling (TUNEL) assays, respectively. The levels of β‑amyloid 1‑42 (Aβ1‑42), pro‑inflammatory factors, such as cyclooxygenase‑2 (COX‑2), tumor necrosis factor‑α (TNF‑α) and interleukin‑1β (IL‑1β) and apoptosis‑associated genes including B cell leukemia/lymphoma 2 (Bcl‑2), Bcl-2‑associated X, apoptosis regulator (Bax), pro‑caspase‑3, inhibitor of κB (IκB‑α) degradation and phosphorylated‑nuclear factor‑κB p65 (p‑NF‑κB p65) activation were analyzed using western blotting. The findings of the present study revealed that CZ2HF treatment significantly attenuated Aβ25‑35‑induced cognitive impairments in rats. Subsequently, CZ2HF treatment markedly inhibited neuronal damage and deletions. Furthermore, CZ2HF reduced TNF‑α, IL‑1β, COX‑2 protein expression levels, Bax/Bcl‑2 ratio, and reduced Aβ1‑42 and active‑caspase‑3 levels. In addition, IκB‑α degradation and p‑NF‑κB p65 activation were reduced by CZ2HF. These findings suggested that CZ2HF treatment improved Aβ25‑35‑induced learning and memory impairment and hippocampal neuronal injury, and its underlying mechanism may be due to the inhibition of neuroinflammation and neuronal apoptosis. CZ2HF may be a potential agent for the treatment of AD.

Ameliorative effect of Alnus japonica ethanol extract on colitis through the inhibition of inflammatory responses and attenuation of intestinal barrier disruption in vivo and in vitro

Inflammatory bowel disease (IBD) is chronic inflammation of the gastrointestinal tract caused by high levels of pro-inflammatory cytokines and epithelial barrier dysfunction. Alnus japonica Steud. (Betulaceae) has been used in traditional Asian medicine. However, the potential of A. japonica for the treatment of intestinal inflammation has not been investigated. This study investigated the effects of ethanol extract from A. japonica bark (AJE) on colonic mucosa injury in mice with dextran sodium sulfate (DSS)-induced colitis. Treatment with AJE ameliorated pathological damage and the histopathologic features of DSS-induced colitis. The administration of AJE also inhibits DSS-induced pro-inflammatory cytokines expression, including interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and cyclooxygenase (COX)-2. Notably, AJE administration attenuated the reduction of tight junction proteins, zonula occludens (ZO)-1 and occludin, in DSS-induced colitis. In addition, AJE increased heme oxygenase (HO)-1 expression and prevented DSS-induced apoptosis in colonic epithelial cells. Furthermore, in vitro studies demonstrated that AJE inhibits TNF-α-induced IL-8, IL-1β, and COX-2 expression in human intestinal epithelial HT-29 cells and tert-butyl hydroperoxide-induced reduction of ZO-1 and occludin expression in human intestinal epithelial Caco-2 cells. AJE-induced HO-1 protein expression was also found in both HT-29 and Caco-2 cells. Taken together, our findings demonstrated that AJE inhibits intestinal inflammation and protects against intestinal barrier disruption in mice with DSS-induced colitis in vivo and human intestinal epithelial cells in vitro. These results suggest that AJE might have beneficial effects for the treatment of IBD.

Tryptanthrin Protects Mice against Dextran Sulfate Sodium-Induced Colitis through Inhibition of TNF-α/NF-κB and IL-6/STAT3 Pathways

Inflammatory bowel disease (IBD) is a notable health problem and may considerably affect the quality of human life. Previously, the protective roles of tryptanthrin (TRYP) against dextran sulfate sodium (DSS) induced colitis has been proved, but the concrete mechanism remained elusive. It has been suggested that TRYP could diminish the weight loss and improve the health conditions of mice with DSS induced colitis. Hematoxylin and eosin staining revealed that TRYP could improve the histopathological structure of the colon tissue. Two signaling pathways (TNF-α/NF-κBp65 and IL-6/STAT3) were investigated using immunochemistry and western blot. The detected concentrations of the two cytokines TNF-α and IL-6 showed that their levels decreased after TRYP treatment of the colitis. The protein expression level of NF-κBp65 in cytoplasm increased after TRYP treatment of the induced colitis. However, the protein level of NF-κBp65 in the nucleus decreased after administration of TRYP. The expression level of IκBα, the inhibitory protein of NF-κBp65, was tested and the results suggested that TRYP could inhibit the degradation of IκBα. The phosphorylation level of STAT3 was inhibited by TRYP and the expression level of STAT3 and p-STAT3 decreased after administration of TRYP. We conclude that TRYP improves the health condition of mice with DSS induced colitis by regulating the TNF-α/NF-κBp65 and IL-6/STAT3 signaling pathways via inhibiting the degradation of IκBα and the phosphorylation of STAT3.

Chemopreventive Effect of Aster glehni on Inflammation-Induced Colorectal Carcinogenesis in Mice

Although Aster glehni is a common dietary herb that has various bioactivities, including anti-diabetic, anti-adipogenic, and anti-inflammatory effects, A. glehni has not been studied in colon cancer. Therefore, we hypothesized the chemopreventive effects of an ethanol extract of A. glehni (AG) on azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colitis-associated cancer (CAC) in mice. In this study, we found that treatment with AG significantly attenuated the AOM/DSS-induced enlargement of the spleen and shortening of the colon. In addition, colonic tumor formation, colonic damage, and increased muscle thickness were significantly reduced in AOM/DSS-induced mice fed AG. Treatment with AG also reduced intestinal interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α production and decreased inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 protein expression in mice with AOM/DSS-induced CAC. Furthermore, AG reduced nuclear factor (NF)-κB activation via phosphorylation and degradation of inhibitor of kappa Bα (IκBα), leading to inhibition of NF-κB p65 nuclear translocation. It also downregulated the expression of NF-κB-related proteins, including the B-cell lymphoma 2 (Bcl-2) family and inhibitors of apoptosis proteins (IAPs), in mice with AOM/DSS-induced CAC. Taken together, these findings suggest that the treatment with AG inhibited colitis-associated colon carcinogenesis in mice, and this chemopreventive effect was strongly mediated by suppression of the NF-κB signaling pathway, indicating that AG could be a promising protective agent against CAC.