Objective To generate and characterize natural killer cell (NK cell)-conditional Cd226 gene knockout mice using Cre-loxP technology, and to explore the role of CD226 on NK cells in alleviating intestinal inflammation in a murine model of ulcerative colitis (UC). Methods NK cell-conditional Cd226 gene knockout mice were generated by crossing loxP-flanked Cd226 mice with Ncr1-Cre mice via the Cre-loxP system. Polymerase chain reaction (PCR) and agarose gel electrophoresis were used for genotyping. A UC model was established by dextran sulfate sodium (DSS) induction. Flow cytometry was performed to analyze CD226 expression levels on NK cells and the infiltration of related immune cells in colon tissues. Hematoxylin-eosin (HE) staining was performed to assess the degree of colonic inflammation. Results DNA gel electrophoresis and flow cytometry confirmed the successful generation of NK cell-specific Cd226 knockout mice. After conditional knockout of Cd226 in NK cells, inflammation in the UC mouse model was alleviated. Flow cytometry results showed a reduced proportion of NK cells in peripheral blood and the colon lamina propria, while HE staining demonstrated attenuated inflammatory responses. Conclusion Specific knockout of Cd226 in NK cells mitigates intestinal inflammation in UC mice by reducing NK cell numbers and inhibiting their pro-inflammatory functions.
Animals ; Colitis, Ulcerative/pathology* ; Killer Cells, Natural/metabolism* ; Mice, Knockout ; T Lineage-Specific Activation Antigen 1 ; Antigens, Differentiation, T-Lymphocyte/genetics* ; Mice ; Disease Models, Animal ; Mice, Inbred C57BL ; Male

Ulcerative colitis (UC) is a chronic and non-specific inflammatory bowel disease (IBD). Huanglian Ganjiang decoction (HGD), derived from ancient book Beiji Qianjin Yao Fang, has demonstrated efficacy in treating UC patients traditionally. Previous research established that the compatibility of cold herb Coptidis Rhizoma + Phellodendri Chinensis Cortex (CP) and hot herb Angelicae Sinensis Radix + Zingiberis Rhizoma (AZ) in HGD synergistically improved colitis mice. This study investigated the compatibility mechanisms through which CP and AZ regulated inflammatory balance in colitis mice. The experimental colitis model was established by administering 3% dextran sulphate sodium (DSS) to mice for 7 days, followed by CP, AZ and CPAZ treatment for an additional 7 days. M1/M2 macrophage polarization levels, glucose metabolites levels and pyruvate dehydrogenase kinase 4 (PDK4) expression were analyzed using flow cytometry, Western blot, immunofluorescence and targeted glucose metabolomics. The findings indicated that CP inhibited M1 macrophage polarization, decreased inflammatory metabolites associated with tricarboxylic acid (TCA) cycle, and suppressed PDK4 expression and pyruvate dehydrogenase (PDH) (Ser-293) phosphorylation level. AZ enhanced M2 macrophage polarization, increased lactate axis metabolite lactate levels, and upregulated PDK4 expression and PDH (Ser-293) phosphorylation level. TCA cycle blocker AG-221 and adeno-associated virus (AAV)-PDK4 partially negated CP's inhibition of M1 macrophage polarization. Lactate axis antagonist oxamate and PDK4 inhibitor dichloroacetate (DCA) partially reduced AZ's activation of M2 macrophage polarization. In conclusion, the compatibility of CP and AZ synergistically alleviated colitis in mice through M1/M2 macrophage polarization balance via PDK4-mediated glucose metabolism reprogramming. Specifically, CP reduced M1 macrophage polarization by restoration of TCA cycle via PDK4 inhibition, while AZ increased M2 macrophage polarization through activation of PDK4/lactate axis.
Animals ; Drugs, Chinese Herbal/chemistry* ; Mice ; Macrophages/immunology* ; Glucose/metabolism* ; Pyruvate Dehydrogenase Acetyl-Transferring Kinase/genetics* ; Male ; Mice, Inbred C57BL ; Humans ; Colitis/drug therapy* ; Disease Models, Animal ; Colitis, Ulcerative/drug therapy* ; Metabolic Reprogramming

Ulcerative colitis (UC) is an inflammatory condition of the intestine, resulting from an increase in oxidative stress and pro-inflammatory mediators. In this study, the extract of endophytic bacterium Rhizobium aegyptiacum was prepared for the first time using liquid chromatography-mass spectrometry (LC-MS). In addition, also for the first time, the protective potential of R. aegyptiacum was revealed using an in vivo rat model of UC. The animals were grouped into four categories: normal control (group I), R. aegyptiacum (group II), acetic acid (AA)‍-induced UC (group III), and R. aegyptiacum-treated AA-induced UC (group IV). In group IV, R. aegyptiacum was administered at 0.2 mg/kg daily for one week before and two weeks after the induction of UC. After sacrificing the rats on the last day of the experiment, colon tissues were collected and subjected to histological, immunohistochemical, and biochemical investigations. There was a remarkable improvement in the histological findings of the colon tissues in group IV, as revealed by hematoxylin and eosin (H&E) staining, Masson's trichrome staining, and periodic acid-Schiff (PAS) staining. Normal mucosal surfaces covered with a straight, intact, and thin brush border were revealed. Goblet cells appeared magenta in color, and there was a significant decrease in the distribution of collagen fibers in the mucosa and submucosal connective tissues. All these findings were comparable to the respective characteristics of the control group. Regarding cyclooxygenase-2 (COX-2) immunostaining, a weak immune reaction was shown in most cells. Moreover, the colon tissues were examined using a scanning electron microscope, which confirmed the results of histological assessment. A regular polygonal unit pattern was seen with crypt orifices of different sizes and numerous goblet cells. Furthermore, the levels of catalase (CAT), myeloperoxidase (MPO), nitric oxide (NO), interleukin-6 (IL-6), and interlukin-1β (IL-1β) were determined in the colonic tissues of the different groups using colorimetric assay and enzyme-linked immunosorbent assay (ELISA). In comparison with group III, group IV exhibited a significant rise (P<0.05) in the CAT level but a substantial decline (P<0.05) in the NO, MPO, and inflammatory cytokine (IL-6 and IL-1β) levels. Based on reverse transcription-quantitative polymerase chain reaction (RT-qPCR), the tumor necrosis factor-‍α (TNF-‍α) gene expression was upregulated in group III, which was significantly downregulated (P<0.05) by treatment with R. aegyptiacum in group IV. On the contrary, the heme oxygenase-1 (HO-1) gene was substantially upregulated in group IV. Our findings imply that the oral consumption of R. aegyptiacum ameliorates AA-induced UC in rats by restoring and reestablishing the mucosal integrity, in addition to its anti-oxidant and anti-inflammatory effects. Accordingly, R. aegyptiacum is potentially effective and beneficial in human UC therapy, which needs to be further investigated in future work.
Animals ; Colitis, Ulcerative/prevention & control* ; Rats ; Male ; Rhizobium ; Disease Models, Animal ; Colon/pathology* ; Rats, Sprague-Dawley ; Oxidative Stress ; Cyclooxygenase 2/metabolism*

OBJECTIVES: To investigate the therapeutic mechanism of 2,6-dimethoxy-1,4-benzoquinone (DMQ) for alleviating dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice. METHODS: Eighteen male C57BL/6J mice were equally randomized into control group, DSS group and DMQ treatment group. In DSS and DMQ groups, the mice were treated with DSS in drinking water to induce UC, and received intraperitoneal injections of sterile PBS or DMQ (20 mg/kg) during modeling. The changes in body weight, disease activity index (DAI), colon length, spleen weight, and colon histological scores of the mice were examined, and the percentages of Th17 and IFN-γ⁺ CD8⁺ T cells in the mesenteric lymph nodes and spleen were analyzed using flow cytometry. The expressions of tight junction proteins (Occludin and ZO-1), proteins associated with inflammasome activation (caspase-1 and p20), IL-1β and TNF-α in the colon tissues were detected using Western blotting or ELISA. In the cell experiment, mouse bone marrow-derived macrophages (BMDMs) primed with lipopolysaccharide (LPS) were treated with DMQ, followed by stmulation with nigericin to activate the classical NLRP3 inflammasome pathway. In cultured human peripheral blood mononuclear cells (PBMCs) treated with either LPS alone or LPS plus nigericin, the effects of DMQ on inflammasome activation, pyroptosis, and cytokine release were evaluated via Western blotting, ELISA, and flow cytometry. RESULTS: In DSS-treated mice, DMQ treatment significantly alleviated DSS-induced body weight loss, colon shortening, spleen enlargement, and colon inflammation. The DMQ-treated mice showed significantly reduced percentages of Th17 cells and IFN-γ⁺ CD8⁺ T cells in the mesenteric lymph nodes and spleen, with increased occludin and ZO-1 expressions and decreased caspase-1 expression in the colon tissue. DMQ obviously inhibited classical NLRP3 inflammasome activation in mouse BMDMs and both the classical and alternative pathways of NLRP3 activation in human PBMCs, causing also suppression of caspase-1-dependent pyroptosis. CONCLUSIONS DMQ ameliorates DSS-induced UC in mice by inhibiting NLRP3 inflammasome activation.
Animals ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Mice, Inbred C57BL ; Colitis, Ulcerative/metabolism* ; Dextran Sulfate/adverse effects* ; Male ; Inflammasomes/metabolism* ; Mice ; Benzoquinones/therapeutic use* ; Th17 Cells ; Caspase 1/metabolism*

INTRODUCTION: Acute severe ulcerative colitis (ASUC) is a significant cause of disease morbidity. One-third of patients with ASUC are steroid refractory. Rescue therapy may not successfully induce remission, necessitating colectomy. We aimed to identify predictors of rescue therapy and colectomy in ASUC assessed within 24 h of admission for early risk stratification. METHODS: We conducted a retrospective cohort study of 58 admissions for ASUC among 47 patients from August 2002 to January 2022. Serum biomarkers assessed were measured on admission. Primary outcomes were the need for rescue therapy during the same admission and colectomy within 1 year of admission. RESULTS: Rescue therapy (all with infliximab) was given in 20 (34.5%) of the admissions. Colectomy was done within 1 year for nine (15.5%) of the admissions. An elevated C-reactive protein (CRP) of >30 mg/L (relative risk [RR] 1.63), a CRP-albumin ratio of >0.85 (RR 1.63), and a composite factor of both CRP > 30 mg/L and age ≥60 years (RR 2.37) were significantly associated with the need for rescue therapy. Hypoalbuminaemia ≤ 25 g/L (RR 4.35) and the use of biologics at presentation (RR 1.54) were significantly associated with colectomy within 1 year of admission, while a CRP of ≥ 80 mg/L was a significant protective factor (RR 0.70). CONCLUSION Patients with ASUC who have elevated CRP or CRP-albumin ratio on admission should be considered at risk for steroid-refractory disease. Those with hypoalbuminaemia on admission and using biologics at presentation are more likely to require colectomy in the first year after admission for ASUC.
Humans ; Colitis, Ulcerative/therapy* ; Colectomy ; Retrospective Studies ; Male ; Female ; Middle Aged ; Adult ; C-Reactive Protein/metabolism* ; Infliximab/therapeutic use* ; Biomarkers/blood* ; Acute Disease ; Aged ; Severity of Illness Index ; Treatment Outcome

OBJECTIVE: To observe the effects of electroacupuncture (EA) at changbing fang (prescription for intestinal disease) on autophagy of colonic cells and gut microbiota in rats with ulcerative colitis (UC), and to explore the mechanism of EA in the treatment of UC. METHODS: Thirty-two SD male rats were randomly divided into a control group, a model group, an EA group and a sham-EA group, with 8 rats in each group. Except the control group, the UC rat model was established by free drinking of 5% dextran sulfate sodium solution for 7 days in the other groups. In the EA group, changbing fang was adopted, in which, EA was applied at "Tianshu" (ST25) and "Shangjuxu" (ST37), at disperse-dense wave and frequency of 10 Hz/50 Hz, for 20 min in each intervention. In the sham-EA group, shallow transcutaneous puncture was performed at the sites, 5 mm away from the points as the EA group, with the same parameters as the EA group. The intervention was delivered once daily for 3 consecutive days. The body weight was measured daily and the disease activity index (DAI) score was calculated before and after intervention. After intervention completion, the colon length was measured. Using HE staining, the colon morphology was observed and the score of colonic pathology was assessed. With ELISA adopted, the contents of tumor necrosis factor (TNF-α), interleukin (IL)-1β, IL-2 and IL-10 in the serum of the rats were detected. The ultrastructure of the colon tissue was observed under electron microscopy. Using Western blotting, the protein expression was detected for microtubule-associated protein 1 light chain 3 (LC3)Ⅱ, LC3Ⅰ, autophagy-related genes (ATG) 5, ATG12, sequestosome 1 (p62), phosphatidylinositol 3-kinase (PI3K), phosphorylated protein kinase B (p-AKT), protein kinase B (AKT), and phosphorylated mammalian target of rapamycin (p-mTOR), mammalian target of rapamycin (mTOR) in the colon tissue. The mRNA expression of PI3K, AKT and m-TOR in the colon tissue was detected by real-time fluorescence quantitative PCR. The 16S rRNA gene sequencing was used to analyze the structure of gut flora in the feces of rats. RESULTS: From day 1 to day 7, compared with the control group, the body weight decreased in the model group, EA group, and SEA group (P<0.05, P<0.01). From day 9 to day 10, the EA group showed an increase in body weight compared with the model group and SEA group (P<0.05, P<0.01). Before intervention, the DAI score in the model group, EA group, and SEA group was higher than the score of the control group, respectively (P<0.01). After intervention, the DAI score in the EA group was reduced compared with the model group and SEA group (P<0.01). Compared with the control group, in the model group, the colon length of rats was shorter (P<0.01); it showed the distorted crypts, thinner mucosal layer, reduced goblet cells, inflammatory cell infiltration and the disarranged histological structure; and the pathological score of the colon tissue increased (P<0.01); the serum contents of TNF-α and IL-1β increased (P<0.01), and those of IL-2 and IL-10 decreased (P<0.01). The structure of colon epithelial cells was disarranged, with cilia pelt off, and a large number of vacuoles in the cytoplasm; the mitochondria were swollen, with unclear structure and cristae partially disappeared; and few autophagosomes were observed. The value of LC3Ⅱ/LC3Ⅰand the protein expression of ATG5 and ATG12 in the colon tissues were reduced (P<0.01), the protein expression of p62 and PI3K, and the values of p-AKT/AKT, and p-mTOR/mTOR increased (P<0.01), and mRNA expression of PI3K, AKT and mTOR was elevated (P<0.01). The indexes of Chao1, Ace and Shannon decreased (P<0.01). At the phylum level, the relative abundance of Firmicutes decreased (P<0.05), that of Bacteroidetes and Proteobacteria increased (P<0.05, P<0.01). At the genus level, the relevant abundance of Lactobacillus decreased (P<0.05), while that of Lachnospiraceae_NK4A136_group and Phascolarctobacterium increased (P<0.01, P<0.05 ). Compared with the model group and SEA group, in the EA group, the colon length increased (P<0.01), the infiltration of inflammatory cells was reduced, the arrangement of intestinal epithelial cells was arranged regularly, with a small amount of shedding, and the pathological score of the colon tissue decreased (P<0.01). The serum contents of TNF-α and IL-1β decreased (P<0.01), and those of IL-2 and IL-10 increased (P<0.01). The colonic epithelial cells were arranged relatively, the morphology of organelles was basically normal, and autophagosomes were visible. The value of LC3Ⅱ/LC3Ⅰand the protein expression of ATG5 and ATG12 in colon tissue increased (P<0.01, P<0.05), the protein expression of p62 and PI3K, and the values of p-AKT/AKT, and p-mTOR/mTOR decreased (P<0.01); and mRNA expression of PI3K, AKT, m-TOR was reduced (P<0.01). The indexes of Chao1, Ace and Shannon increased (P<0.01). At the phylum level, the relative abundance of Firmicutes increased (P<0.01), while that of Bacteroidetes decreased (P<0.01). At the genus level, the relative abundance of Lactobacillus increased (P<0.05), whereas that of Lachnospiraceae_NK4A136_group decreased (P<0.01). When compared with the model group, the relative abundance of Proteobacteria decreased (P<0.05), and that of Phascolarctobacterium was reduced (P<0.05) in the EA group. CONCLUSION EA at changbingfang alleviates UC symptoms probably through inhibiting the PI3K/AKT/mTOR signaling pathway to regulate colonic autophagy and improve the intestinal flora.
Animals ; Electroacupuncture ; Colitis, Ulcerative/metabolism* ; Male ; Rats ; Gastrointestinal Microbiome ; Rats, Sprague-Dawley ; Colon/metabolism* ; Humans ; Autophagy ; Acupuncture Points ; Tumor Necrosis Factor-alpha/genetics* ; Interleukin-10/genetics*

This study investigated the functions and regulatory mechanism of Portulacae Herba and its chemical components on the Toll-like receptor 4(TLR4)/myeloid differentiation primary response 88(MyD88)/nuclear factor kappa B(NF-κB) inflammatory signaling pathway in the colon tissue of mice with dextran sodium sulfate(DSS)-induced ulcerative colitis(UC). A total of 35 mice were randomly divided into groups, including a blank group, a model group, a mesalazine group(0. 5 g·kg~(-1)), and low, medium,and high dose alkaloids from Portulacae Herba groups(9, 18, 36 mg·kg~(-1)), and a combination treatment group, with 5 mice in each group. The blank group was given purified water, while the other groups were continuously given a 3% DSS solution for 7 days to induce the UC model. From day 8 onwards, the treatment group received oral gavage according to the prescribed doses for 14 days. The overall condition, body weight, stool characteristics, and presence of blood in the stool were recorded daily. After the experiment, the disease activity index(DAI) was assessed for each group, and colon length was measured. Histopathological changes in colon tissue were examined using hematoxylin-eosin(HE) staining. The levels of pro-inflammatory cytokines, tumor necrosis factor-α(TNF-α),and interleukin-1β( IL-1β) in serum were measured by enzyme-linked immunosorbent assay( ELISA). The protein and m RNA expression of TLR4, MyD88, and NF-κB in colon tissue were measured using Western blot and quantitative real-time PCR(qPCR).Compared to the blank group, the model group showed a significant decrease in body weight, a notable increase in DAI scores, a significant shortening of colon length, and evident histopathological damage. The levels of inflammatory cytokines TNF-α and IL-1β in the serum were significantly elevated, and the protein and m RNA expression of TLR4, MyD88, and NF-κB in colon tissue were significantly up-regulated. In contrast, the alkaloids from Portulacae Herba treatment groups significantly improved symptoms and reduced body weight loss in mice, decreased DAI scores, alleviated colon shortening, lowered serum levels of TNF-α and IL-1β,significantly down-regulated the expression levels of TLR4, MyD88, and NF-κB proteins and genes in colon tissue, as well as reduced histopathological damage. Therefore, the study suggests that alkaloids from Portulacae Herba can alleviate intestinal inflammation damage in DSS-induced UC mice, with its mechanism involving the TLR4/MyD88/NF-κB signaling pathway.
Animals ; Colitis, Ulcerative/immunology* ; Toll-Like Receptor 4/immunology* ; Myeloid Differentiation Factor 88/metabolism* ; Mice ; NF-kappa B/metabolism* ; Signal Transduction/drug effects* ; Male ; Alkaloids/administration & dosage* ; Drugs, Chinese Herbal/administration & dosage* ; Humans ; Female ; Colon/metabolism* ; Disease Models, Animal

The efficacy of Xiangmei Pills on rats with ulcerative colitis(UC) was investigated by characterizing the spectrum of the active chemical components of Xiangmei Pills. Rapid identification and classification of the main chemical components were performed,and the therapeutic effects of Xiangmei Pills on the proteins and intestinal flora of UC rats were analyzed to explore the mechanism of its action in treating UC. Fifty SD rats were acclimatized to feeding for 3 d and randomly divided into blank group, model group,mesalazine group(0. 4 g·kg~(-1)), low-dose group of Xiangmei Pills(1. 89 g·kg~(-1)), and high-dose group of Xiangmei Pills(5. 67 g·kg~(-1)), with 10 rats in each group. 5% dextrose sodium sulfate(DSS) was given by gavage to induce the male SD rat model with UC,and the corresponding medicinal solution was given by gavage after 10 days, respectively. The therapeutic effect of Xiangmei Pills on rats with UC was evaluated according to body mass, disease activity index(DAI), and hematoxylin-eosin(HE) staining, and the histopathological changes in the colon were observed. Ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap high-resolution mass spectrometry(UHPLC-Q-Orbitrap HRMS) technique was used to rapidly and accurately identify the main chemical constituents of Xiangmei Pills. Immunohistochemistry was used to detect the expression of aryl hydrocarbon receptor(AhR),interferon-γ(IFN-γ), mucin-2(MUC-2), and cytochrome P450 1A1(CYP1A1) in colon tissue. Interleukin-22(IL-22) expression in colon tissue was detected by immunofluorescence. The 16S r DNA high-throughput sequencing technique was used to study the modulatory effects of Xiangmei Pills on the intestinal flora structure of rats with UC. Pharmacodynamic results showed that compared with that of the blank group, the colon tissue of the model group was congested, and ulcers were visible in the mucosa; compared with that in the model group, the histopathology of the colon of the rats with UC in the groups of Xiangmei Pills were improved, with scattered ulcers and reduced inflammatory cell infiltration. Chemical analysis showed that a total of 45 components were identified by mass spectrometry information, including 15 phenolic acids, 8 coumarins, 15 organic acids, 3 amino acids, 2 flavonoids, and 2 other components. Compared with those in the blank group, the levels of Ah R, CYP1A1, MUC-2, and IL-22 proteins in the colon tissue of rats in the model group were significantly decreased, and the level of IFN-γ protein was significantly increased; the intestinal flora of rats in the model group was disorganized, with a decrease in the abundance of the flora; the relative abundance of Bacteroidetes,unclassified genera of Ascomycetes, Prevotella of the Prevotella family, and Prevotella decreased significantly, and that of Firmicutes decreased, but the difference was not statistically significant. The relative abundance of Bacteroidetes, Bifidobacterium, and Lactobacillus increased significantly. Compared with those of the model group, the levels of Ah R, CYP1A1, MUC-2, and IL-22proteins in the colonic tissue of the groups of Xiangmei Pills were significantly higher, and the levels of IFN-γ proteins were significantly lower. The recovery of the intestinal flora was accelerated, and the diversity of the intestinal flora was significantly increased. The relative abundance of Bacteroidetes was significantly increased, and that of unclassified genera of Ascomycetes,Lactobacillus, Prevotella of the Prevotella family, and Prevotella was significantly increased. The relative abundance of Bacteroidetes and Bifidobacterium was significantly decreased. This study demonstrated that Xiangmei Pills can effectively treat UC, mainly through the phenolic acid and organic acid components to stimulate the intestinal barrier, regulate protein expression and the relative abundance and diversity of intestinal flora, and play a role in the treatment of UC.
Animals ; Colitis, Ulcerative/metabolism* ; Drugs, Chinese Herbal/chemistry* ; Rats, Sprague-Dawley ; Male ; Rats ; Gastrointestinal Microbiome/genetics* ; Chromatography, High Pressure Liquid ; Humans ; Mass Spectrometry ; RNA, Ribosomal, 16S/genetics* ; Bacteria/drug effects*

This study employed 16S r RNA gene high-throughput sequencing and metabolomics to explore the mechanism of Angelicae Dahuricae Radix polysaccharides(RP) in the treatment of ulcerative colitis(UC). A mouse model of UC was induced with 2. 5% dextran sulfate sodium. The therapeutic effects of RP on UC in mice were evaluated based on changes in body weight, disease activity index( DAI), and colon length, as well as pathological changes. RT-qPCR was performed to assess the m RNA levels of interleukin(IL)-6, IL-1β, tumor necrosis factor(TNF)-α, myeloperoxidase(MPO), mucin 2(Muc2), Occludin, Claudin2, and ZO-1 in the mouse colon tissue. ELISA was employed to measure the expression of IL-1β and TNF-α in the colon tissue. The intestinal permeability of mice was evaluated by the fluorescent dye permeability assay. Immunohistochemistry was employed to detect the expression of Muc2 and occludin in the colon tissue. Changes in gut microbiota and metabolites were analyzed by 16S r RNA sequencing and ultra-high-performance liquid chromatography coupled with quadrupole-orbitrap mass spectrometry( UPLC-Q-Exactive Plus Orbitrap MS), respectively. The results indicated that low-dose RP alleviated general symptoms, reduced colonic inflammation and intestinal permeability, and promoted Muc2 secretion and tight junction protein expression in UC mice. In addition, low-dose RP increased gut microbiota diversity in UC mice and decreased the relative abundance of harmful bacteria such as Ochrobactrum and Streptococcus. Twenty-seven differential metabolites were identified in feces, and low-dose RP restored the levels of disturbed metabolites. Notably, arginine and proline metabolism were the most significantly altered amino acid metabolic pathways following lowdose RP intervention. In conclusion, RP can ameliorate general symptoms, inhibit colonic inflammation, and maintain intestinal mucosal barrier integrity in UC mice by modulating gut microbiota composition and arginine and proline metabolism.
Animals ; Gastrointestinal Microbiome/drug effects* ; Colitis, Ulcerative/genetics* ; Mice ; Male ; Drugs, Chinese Herbal/administration & dosage* ; Polysaccharides/administration & dosage* ; Angelica/chemistry* ; Humans ; Colon/metabolism* ; Disease Models, Animal ; Mucin-2/metabolism* ; Tumor Necrosis Factor-alpha/metabolism*

This study delves into the mechanism of total flavone of Abelmoschus manihot(TFA) in treating ulcerative colitis(UC) and depression via inhibiting M1 polarization of macrophages and reshaping intestinal flora and glycerolphospholipid metabolism. The study established a mouse model of UC and depression induced by chronic restraint stress(CRS) and dextran sulfate sodium(DSS). The fecal microbiota transplantation(FMT) experiment after TFA intervention was conducted. Mice in the FMT donor group were modeled and treated, and fecal samples were taken to prepare the bacterial solution. Mice in the FMT receptor group were treated with antibiotic intervention, and then administered bacterial solution by gavage from mice in the donor group, followed by UC depression modeling. After the experiment, behavioral tests were conducted to evaluate depressive-like behaviors by measuring the levels of 5-hydroxytryptamine(5-HT) and brain-derived neurotrophic factor(BDNF) in the hippocampus of mice. The levels of tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),and interleukin-1β(IL-1β)in the brain and colon tissue of mice were also measured, and the polarization status of macrophages was evaluated by measuring the mRNA levels of CD86 and CD206. 16S ribosomal RNA(16S rRNA) sequencing technology was used to analyze changes in the intestinal flora of mice. Wide target lipidomics was used to detect serum lipid metabolite levels in mice after FMT,and correlation analysis was conducted between lipids and differential intestinal flora significantly regulated by TFA. In vitro experiments, representative glycerophospholipid metabolites and glycerophospholipid inhibitors were used to intervene in Raw264.7 macrophages, and the mRNA levels of TNF-α,IL-6,IL-1β,CD86,and CD206 were detected. The results showed that TFA and FMT after intervention could significantly improve depressive-like behavior and intestinal inflammation in mice with UC and depression, significantly downregulate pro-inflammatory cytokines and CD86 mRNA expression in brain and colon tissue, inhibiting M1 polarization of macrophages, and significantly upregulate CD206 mRNA expression, promoting M2 polarization of macrophages. In addition, the high-dose group had a more significant effect. After TFA intervention, FMT significantly corrected the metabolic disorder of glycerophospholipids in mice with UC and depression, and there was a significant correlation between differential intestinal flora and glycerophospholipids. In vitro experiments showed that glycerophospholipid metabolites, especially lysophosphatidylcholine(LPC),significantly upregulated pro-inflammatory cytokines and CD86 mRNA expression, promote M1 polarization of macrophages, while glycerophospholipid inhibitors had the opposite effect. The results indicate that TFA effectively treats depression and UC by correcting intestinal flora dysbiosis and reshaping glycerophospholipid metabolism, thereby inhibiting M1 polarization of macrophages.
Animals ; Mice ; Gastrointestinal Microbiome/drug effects* ; Abelmoschus/chemistry* ; Macrophages/metabolism* ; Colitis, Ulcerative/immunology* ; Flavones/administration & dosage* ; Male ; Depression/genetics* ; Glycerophospholipids/metabolism* ; Humans ; Drugs, Chinese Herbal/administration & dosage* ; Mice, Inbred C57BL