scholarly journals Nicotinamide Ameliorates Dextran Sulfate Sodium-Induced Chronic Colitis in Mice through Its Anti-Inflammatory Properties and Modulates the Gut Microbiota

2021 ◽  
Vol 2021 ◽  
pp. 1-19
Author(s):  
Kai Kang ◽  
Yue Sun ◽  
Dan Pan ◽  
Bing Chang ◽  
Li-Xuan Sang
Keyword(s):  
Gut Microbiota ◽  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Activity Index ◽  
Alpha Diversity ◽  
Short Chain Fatty Acids ◽  
Enzyme Linked Immunosorbent Assay ◽  
Control Group ◽  
Chronic Colitis ◽  
Anti Inflammatory

Vitamin B (nicotinamide (NAM)), one of the most important nutritional components for humans, exerts anti-inflammatory activity. This study was aimed at investigating the effect of NAM on the gut microbiota and short-chain fatty acids (SCFAs) in mice with chronic colitis. Colitis was induced in C57BL/6 male mice by administration of 1.5% dextran sulfate sodium (DSS), and the mice were intraperitoneally injected with normal saline (NS) or NAM. NAM treatment ameliorated weight loss and changes in colon length, disease activity index (DAI) score, and histologic scores. Moreover, enzyme-linked immunosorbent assay (ELISA) analysis of LPL cells revealed that the level of interleukin- (IL-) 6, IL-12p70, IL-1β, tumor necrosis factor- (TNF-) α, interferon- (IFN-) γ, IL-21, and IL-17A was increased, while IL-10 was reduced, in the chronic colitis group compared to the control group, but the levels of all these factors were restored after NAM treatment. Then, 16S rRNA sequencing of the large intestinal content was performed, and analysis of alpha diversity and beta diversity showed that the richness of the gut microbiota was decreased in the DSS group compared to the control group and restored after NAM treatment. In addition, NAM modulated specific bacteria, including Odoribacter, Flexispira, and Bifidobacterium, in the NAM+chronic colitis group. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis indicated that NAM treatment restored disruptions in the functions of the gut microbiota (replication and repair, cell motility) in mice with DSS-induced colitis. Furthermore, NAM also restored the reduction in valeric acid in mice with DSS-induced chronic colitis. Our results suggest that NAM treatment could alleviate DSS-induced chronic colitis in mice by inhibiting inflammation and regulating the composition and function of gut microbiota.

scholarly journals Dietary Alaska Pollock Protein Attenuates the Experimental Colitis Induced by Dextran Sulfate Sodium via Regulation of Gut Microbiota and Its Metabolites in Mice

Metabolites ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 44
Author(s):  
Genki Tanaka ◽  
Nozomi Hagihara ◽  
Ryota Hosomi ◽  
Takaki Shimono ◽  
Seiji Kanda ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Activity Index ◽  
Body Weight Loss ◽  
Disease Activity Index ◽  
Experimental Colitis ◽  
Short Chain Fatty Acids ◽  
Spleen Weight ◽  
Reduced Body

Protein derived from fish has not only nutritional properties but also health-promoting properties. Few studies have examined the effect of dietary Alaska pollock protein (APP) on the anticolitis effect reported to be associated with metabolic syndrome (MetS). This study investigated the effect of APP intake on colitis symptoms, gut microbiota, and its metabolites in the experimental colitis mouse model induced by dextran sulfate sodium (DSS). Male C57BL/6J mice were divided into three groups: (1) DSS-untreated mice fed an American Institute of Nutrition (AIN) 93G diet (protein source is casein), (2) DSS-treated mice fed an AIN93G diet, and (3) DSS-treated mice fed an APP diet. After the mice were fed the diets for 21 days, experimental colitis was induced by three cycles of 2% DSS administration for 5 days followed by washouts over the course of 5 days. APP-reduced body weight loss increased the disease activity index, and elevated spleen weight and alleviated colon length shortening and colonic tissue damage. Furthermore, APP altered the structure and composition of the microbiota and short-chain fatty acids in feces. Since APP intake alleviates experimental colitis induced by DSS administration through alterations in the gut microbiota and its metabolites, we deduced that APP would inhibit MetS progression via colitis suppression.

scholarly journals Absorption of Codonopsis pilosula Saponins by Coexisting Polysaccharides Alleviates Gut Microbial Dysbiosis with Dextran Sulfate Sodium-Induced Colitis in Model Mice

2018 ◽  
Vol 2018 ◽  
pp. 1-18 ◽  
Author(s):  
Yaping Jing ◽  
Anping Li ◽  
Zhirong Liu ◽  
Pingrong Yang ◽  
Junshu Wei ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Gut Microbiota ◽  
Inflammatory Cytokines ◽  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Short Chain Fatty Acids ◽  
Short Chain ◽  
Codonopsis Pilosula ◽  
Anti Inflammatory ◽  
Chain Fatty Acids

Objectives. Inflammatory Bowel Disease (IBD) is an autoimmune disease, and the gut microbiota has become a new therapeutic target. Herbal medicine (HM) has shown good efficacy in the clinical treatment of IBD; however, the synergistic actions of the dominant chemicals in HM decoctions are unclear. Methods. In this study, we explored whether the complicated interconnections between HM and the gut microbiota could allow crosstalk between HM ingredients. Saponins and polysaccharides, i.e., the dominant chemicals in the Codonopsis pilosula Nannf (CPN) decoction, were investigated in a dextran sulfate sodium- (DSS-) induced mouse model. Bacterial 16S rRNA sequencing analyzed the change of gut microbiota structure and diversity. Gas chromatography (GC) determined the content of short-chain fatty acids (SCFAs) in feces. ELISA detected the expression of proinflammatory and anti-inflammatory cytokines associated with TH17/Treg balance. UPLC-QTOF-MS technology combined with PKsolver software analyzed the absorption of the highest exposure for monomeric compounds of CPN saponins in serum. The results indicated that CPN polysaccharides showed prebiotic-like effects in mice with DSS-induced colitis by simultaneously stimulating the growth of three important probiotics, i.e., Bifidobacterium spp., Lactobacillus spp., and Akkermansia spp., and inhibiting the growth of pathogenic bacteria, including Desulfovibrio spp., Alistipes spp., and Helicobacter spp. Moreover, CPN polysaccharides improved intestinal metabolism, enhanced the production of short-chain fatty acids, upregulated the expression of anti-inflammatory cytokines and downregulated the secretion of proinflammatory cytokines correlated with Th17/Treg balance, promoted the absorption of certain CPN saponins in the serum, and stimulated recovery of the holistic gut microbiota. Conclusion. CPN polysaccharides have the good prebiotic properties and shown good application prospects in the prevention and treatment of acute colitis. These findings provide insights into the specific bacteria responsible for active, inactive biotransformation of HM ingredients and those that are altered by HM administration.

Desmethylbellidifolin Attenuates Dextran Sulfate Sodium-Induced Colitis: Impact on Intestinal Barrier, Intestinal Inflammation and Gut Microbiota

Planta Medica ◽  
2021 ◽  
Author(s):  
Jiaqi Wu ◽  
Yuzheng Wu ◽  
Yue Chen ◽  
Mengyang Liu ◽  
Haiyang Yu ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Gut Microbiota ◽  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Intestinal Inflammation ◽  
Activity Index ◽  
Intestinal Barrier ◽  
Intestinal Barrier Function ◽  
Function Evaluation ◽  
Biological Drugs

AbstractUlcerative colitis has been recognized as a chronic inflammatory disease predominantly disturbing the colon and rectum. Clinically, the aminosalicylates, steroids, immunosuppressants, and biological drugs are generally used for the treatment of ulcerative colitis at different stages of disease progression. However, the therapeutic efficacy of these drugs does not satisfy the patients due to the frequent drug resistance. Herein, we reported the anti-ulcerative colitis activity of desmethylbellidifolin, a xanthone isolated from Gentianella acuta, in dextran sulfate sodium-induced colitis in mice. C57BL/6 mice were treated with 2% dextran sulfate sodium in drinking water to induce acute colitis. Desmethylbellidifolin or balsalazide sodium was orally administrated once a day. Biological samples were collected for immunohistological analysis, intestinal barrier function evaluation, cytokine measurement, and gut microbiota analysis. The results revealed that desmethylbellidifolin alleviated colon shortening and body weight loss in dextran sulfate sodium-induced mice. The disease activity index was also lowered by desmethylbellidifolin after 9 days of treatment. Furthermore, desmethylbellidifolin remarkably ameliorated colonic inflammation through suppressing the expression of interleukin-6 and tumor necrosis factor-α. The intestinal epithelial barrier was strengthened by desmethylbellidifolin through increasing levels of occludin, ZO-1, and claudins. In addition, desmethylbellidifolin modulated the gut dysbiosis induced by dextran sulfate sodium. These findings suggested that desmethylbellidifolin effectively improved experimental ulcerative colitis, at least partly, through maintaining intestinal barrier integrity, inhibiting proinflammatory cytokines, and modulating dysregulated gut microbiota.

scholarly journals APicrorhiza kurroaDerivative, Picroliv, Attenuates the Development of Dextran-Sulfate-Sodium-Induced Colitis in Mice

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
De-Kui Zhang ◽  
Jian-Jie Yu ◽  
Yu-Min Li ◽  
Li-Na Wei ◽  
Yi Yu ◽  
...  
Keyword(s):  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Activity Index ◽  
Quantitative Polymerase Chain Reaction ◽  
Critical Role ◽  
Disease Activity Index ◽  
Enzyme Linked Immunosorbent Assay ◽  
Histological Score ◽  
Polymerase Chain ◽  
Histology Score

Background. Free radicals and proinflammatory cytokines have been shown to play a critical role in the pathogenesis of ulcerative colitis (UC). Picroliv, aPicrorhiza kurroaderivative, has been demonstrated to have antioxidant and anti-inflammatory effect. The purpose of the study was to investigate the effects of picroliv on experimental model of UC in mice.Materials and Methods. Picroliv was administrated orally by gavage to mice with colitis induced by dextran sulfate sodium (DSS). Disease activity index (DAI), colon length, and histology score were observed. Myeloperoxidase (MPO) activity, and SOD, MDA concentrations were measured by enzyme-linked immunosorbent assay (ELISA) while the expression of cytokine mRNAs was studied by real-time-quantitative polymerase chain reaction and also ELISA. The expression of NF-κB p65 was observed by immunohistochemistry staining and western blotting.Results. A significant improvement was observed in DAI and histological score in mice treated with picroliv, and incerased MPO activity, MDA concentrations, and the expression of IL-1β, TNF-α, and NF-κB p65 in mice with DSS-induced colitis were significantly reduced while decreased SOD level increased following administration of picroliv.Conclusion. The administration of picroliv leads to an amelioration of DSS-induced colitis, suggesting administration of picroliv may provide a therapeutic approach for UC.

scholarly journals Alleviation Effects of Bifidobacterium animalis subsp. lactis XLTG11 on Dextran Sulfate Sodium-Induced Colitis in Mice

2021 ◽  
Vol 9 (10) ◽  
pp. 2093
Author(s):  
Nana Wang ◽  
Song Wang ◽  
Baofeng Xu ◽  
Fei Liu ◽  
Guicheng Huo ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Signaling Pathway ◽  
Inflammatory Cytokines ◽  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Activity Index ◽  
Intestinal Barrier Function ◽  
Spleen Weight ◽  
Colon Tissue ◽  
Bifidobacterium Animalis

Inflammatory bowel disease (IBD) is a chronic immune-related disease, which can occur through the dysfunction of the immune system caused by the imbalance of gut microbiota. Previous studies have reported the beneficial effects of Bifidobacterium on colitis, while the related mechanisms behind these effects have not been fully elucidated. The aim of our study is to investigate the alleviation effect of Bifidobacterium animalis subsp. lactis XLTG11 (B. lactis) on dextran sulfate sodium (DSS)-induced colitis and its potential mechanism. The results showed that B. lactis XLTG11 significantly decreased weight loss, disease activity index score, colon shortening, myeloperoxide activity, spleen weight, and colon tissue damage. Additionally, B. lactis XLTG11 significantly decreased the levels of pro-inflammatory cytokines and increased the level of anti-inflammatory cytokine. Meanwhile, high doses of B. lactis XLTG11 significantly up-regulated the expression of tight junction proteins and inhibited activation of Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MYD88)/nuclear factor-κB (NF-κB) signaling pathway. Furthermore, B. lactis XLTG11 increased the gut microbiota diversity and modulated gut microbiota composition caused by DSS. Moreover, Spearman’s correlation analysis also found that several specific gut microbiota were significantly correlated with colitis-related indicators. These results demonstrated that B. lactis XLTG11 can alleviate DSS-induced colitis by inhibiting the activation of the TLR4/MYD88/NF-κB signaling pathway, regulating inflammatory cytokines, improving intestinal barrier function, and modulating the gut microbiota.

scholarly journals Galangin Protects against Symptoms of Dextran Sodium Sulfate-Induced Acute Colitis by Activating Autophagy and Modulating the Gut Microbiota

Nutrients ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 347 ◽  
Author(s):  
Hongzhuan Xuan ◽  
Aiqun Ou ◽  
Shengyu Hao ◽  
Jiajun Shi ◽  
Xiaolu Jin
Keyword(s):  
Gut Microbiota ◽  
Activity Index ◽  
Disease Activity Index ◽  
Short Chain Fatty Acids ◽  
Control Group ◽  
Necrosis Factor Alpha ◽  
Bowel Diseases ◽  
Pre Treatment ◽  
Related Proteins

Galangin is a natural flavonoid that has been reported to provide substantial health benefits. Nevertheless, little is known about the potential effects of galangin against inflammatory bowel diseases. Here, an in vivo study was performed to investigate the preventive effects of galangin against dextran sulphate sodium (DSS)-induced acute murine colitis, which mimics the symptoms of human ulcerative colitis (UC). Pre-treatment with galangin (15 mg/kg, p.o.) resulted in a significant decreased in the macroscopic signs of DSS-induced colitic symptoms, including a decreased disease activity index, prevention of the colon length shortening, and alleviation of the pathological changes occurring in the colon. Colonic pro-inflammatory mediators, including tumor necrosis factor-alpha, interleukin (IL)-1 beta, and IL-6, as well as myeloperoxidase activities were decreased following galangin pre-treatment when compared with the DSS control group. Moreover, galangin pre-treatment significantly increased the expressions of autophagy-related proteins and promoted the formation of autophagosome in the colon. Galangin pre-treatment increased the diversity of the gut microbiota, and this was accompanied by increased levels of short-chain fatty acids. These observed changes could involve the modulating effects conferred by galangin in relation to some specific bacteria populations, including the recovery of Lactobacillus spp., and increased Butyricimonas spp. Overall, these results support the use of galangin in the prevention of UC.

scholarly journals Regulatory effect of Garidisan on dysbiosis of the gut microbiota in the mouse model of ulcerative colitis induced by dextran sulfate sodium

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Ling-yan Pei ◽  
Yu-shi Ke ◽  
Huan-hu Zhao ◽  
Wei-zhi Liu ◽  
Lin Wang ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Mouse Model ◽  
Gut Microbiota ◽  
Therapeutic Effect ◽  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Control Group ◽  
Group Model ◽  
Regulatory Effect ◽  
Model Group

Abstract Background Ulcerative colitis (UC) is a modern refractory disease, and its etiology has been difficult to discern. Studies have shown that UC is closely associated with the gut microbiota. Garidisan is composed of wild poppy and Artemisia frigida Willd and is commonly used for the treatment of UC in Inner Mongolia, China. In clinical settings, Garidisan has been found to treat UC effectively, with low recurrence. Previous studies have shown that Garidisan has a good therapeutic effect on mice with UC, but the therapeutic mechanism is still unclear. In this study, we investigated the regulatory effect of Garidisan on dysbiosis of the gut microbiota in a UC mouse model and explored the possible mechanism of the therapeutic effect of Garidisan on UC. Methods The UC mouse model was established by the dextran sulfate sodium (DSS) circulating free water drinking method, and the luminal contents were sampled under sterile conditions. High-throughput sequencing of the 16S rRNA gene V3 + V4 region of the luminal contents of the control group, model group, and Garidisan group was conducted, and clustering of operational taxonomic units (OTUs) and species annotation were performed. The differences in species composition and microbial community structure between individual groups of samples were analyzed using MetaStat, LefSe, rank sum test, and Bayesian causal network analysis. Results The UC mouse model was successfully established and the sequencing results were of adequate quality. There were significant differences in the diversity of luminal contents between the control group, model group, and Garidisan group, and the differences between groups were greater than those within any group. The therapeutic effect of Garidisan on UC is attributed to the direct effect on the Lachnospiraceae family of bacteria. Conclusion Garidisan has a good regulatory effect on the gut microbiota, and Lachnospiraceae could be an important direct target of Garidisan for the treatment of UC.

scholarly journals Effect of Electroacupuncture in Mice with Dextran Sulfate Sodium-Induced Colitis and the Influence of Gut Microbiota

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Geng-Hao Liu ◽  
Hsuan-Miao Liu ◽  
Yu-Sheng Chen ◽  
Tzung-Yan Lee
Keyword(s):  
Gut Microbiota ◽  
Tight Junctions ◽  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Experimental Colitis ◽  
16S Rrna Gene Sequencing ◽  
Control Group ◽  
Rrna Gene ◽  
Colonic Inflammation ◽  
The Relationship

Background. The relationship between inflammatory bowel disease and gut microbiota is inextricable. Electroacupuncture (EA) can alleviate acute experimental colitis, but the performance of intestinal microorganisms and the mechanism are still not fully understood. We investigated the relationship between the EA and gut microbes and clarified the role of tight junction and adiponectin in the anti-inflammatory effect of EA. Methods. Male C57BL/6 mice were randomized into three groups: normal control, dextran sulfate sodium- (DSS-) induced ulcerative colitis (DSS), and DSS with EA ST36 (DSS + EA). Mice body weight, DAI score, colon length, and histological score were evaluated for colitis severity. Colonic inflammation and tight junctions were demonstrated by the immunohistochemical (IHC) method. Systemic responses were confirmed by plasma cytokines and adiponectin with multiplex immunoassays. Gut microbiome profiling was conducted by 16S rRNA gene sequencing. Results. EA had benefit in relieving both macroscopic and microscopic colonic inflammation. It can reduce disease activity, maintain colon length, and ameliorate histological inflammatory reaction. In IHC stain, EA decreased CD11b, F4/80, TLR4, and MyD88 and preserved claudin-1 and ZO-1 expression. Compared with the control group, the DSS group showed elevated levels of CRP, IFN-γ, TNF-α, and IL-6, but decreased adiponectin. These changes were reversed by EA, accompanied by modulation of the overall structure of gut microbiota. Conclusion. Our findings suggest that EA exerts its therapeutic effect by TLR4 signaling via the MyD88-dependent pathway. EA could increase adiponectin, maintain mucosal tight junctions, and modulate gut microbiota.

scholarly journals Protective Effect of Tuna Bioactive Peptide on Dextran Sulfate Sodium-Induced Colitis in Mice

Marine Drugs ◽  
2021 ◽  
Vol 19 (3) ◽  
pp. 127
Author(s):  
Xing-Wei Xiang ◽  
Xiao-Ling Zhou ◽  
Rui Wang ◽  
Cong-Han Shu ◽  
Yu-Fang Zhou ◽  
...  
Keyword(s):  
Bioactive Peptides ◽  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Intestinal Flora ◽  
Intestinal Barrier ◽  
Short Chain Fatty Acids ◽  
The Body ◽  
Inflammatory Factors ◽  
High Dose ◽  
Anti Inflammatory

Bioactive peptides isolated from marine organisms have shown to have potential anti-inflammatory effects. This study aimed to investigate the intestinal protection effect of low molecular peptides (Mw < 1 kDa) produced through enzymatic hydrolysis of tuna processing waste (tuna bioactive peptides (TBP)) on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in BALB/c mice. Here, we randomly divided twenty-four male BALB/c mice into four groups: (i) normal (untreated), (ii) DSS-induced model colitis, (iii) low dose TBP+DSS-treated (200 mg/kg/d), and (iv) high dose TBP+DSS-treated groups (500 mg/kg/d). The results showed that TBP significantly reduced mice weight loss and improved morphological and pathological characteristics of colon tissues. In addition, it increased the activities of antioxidant enzymes (SOD and GSH-Px) and decreased inflammatory factors (LPS, IL-6, and TNF-α) expression. TBP increased the gene expression levels of some tight junction (TJ) proteins. Moreover, TBP increased the short-chain fatty acids (SCFAs) levels and the diversity and imbalance of intestinal flora. Therefore, TBP plays some protective roles in the intestinal tract by enhancing antioxidant and anti-inflammatory abilities of the body, improving the intestinal barrier and metabolic abnormalities, and adjusting intestinal flora imbalance.

scholarly journals Akkermansia muciniphila Exerts Strain-Specific Effects on DSS-Induced Ulcerative Colitis in Mice

2021 ◽  
Vol 11 ◽  
Author(s):  
Qing Liu ◽  
Wenwei Lu ◽  
Fengwei Tian ◽  
Jianxin Zhao ◽  
Hao Zhang ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Gut Microbiota ◽  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Immune Defense ◽  
Rapid Screening ◽  
Comparative Genomic ◽  
Control Group ◽  
Akkermansia Muciniphila ◽  
Positive Effects

Akkermansia muciniphila is a commensal bacterium of the gut mucus layer. Although both in vitro and in vivo data have shown that A. muciniphila strains exhibit strain-specific modulation of gut functions, its ability to moderate immunity to ulcerative colitis have not been verified. We selected three isolated human A. muciniphila strains (FSDLZ39M14, FSDLZ36M5 and FSDLZ20M4) and the A. muciniphila type strain ATCC BAA-835 to examine the effects of different A. muciniphila strains on dextran sulfate sodium-induced colitis. All of the A. muciniphila strains were cultured anaerobically in brain heart infusion medium supplemented with 0.25% type II mucin from porcine stomach. To create animal models, colitis was established in C57BL/6 mice which randomly divided into six groups with 10 mice in each group by adding 3% dextran sulfate sodium to drinking water for 7 days. A. muciniphila strains were orally administered to the mice at a dose of 1 × 109 CFU. Only A. muciniphila FSDLZ36M5 exerted significant protection against ulcerative colitis (UC) by increasing the colon length, restoring body weight, decreasing gut permeability and promoting anti-inflammatory cytokine expression. However, the other strains (FSDLZ39M14, ATCC BAA-835 and FSDLZ20M4) failed to provide these effects. Notably, A. muciniphila FSDLZ20M4 showed a tendency to exacerbate inflammation according to several indicators. Gut microbiota sequencing showed that A. muciniphila FSDLZ36M5 supplementation recovered the gut microbiota of mice to a similar state to that of the control group. A comparative genomic analysis demonstrated that the positive effects of A. muciniphila FSDLZ36M5 compared with the FSDLZ20M4 strain may be associated with specific functional genes that are involved in immune defense mechanisms and protein synthesis. Our results verify the efficacy of A. muciniphila in improving UC and provide gene targets for the efficient and rapid screening of A. muciniphila strains with UC-alleviating effects.

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