Zhexing Shou

Extracellular Vesicles Derived from Bone Marrow Mesenchymal Stem Cells Protect against Experimental Colitis via Attenuating Colon Inflammation, Oxidative Stress and Apoptosis

The administration of bone mesenchymal stem cells (BMSCs) could reverse experimental colitis, and the predominant mechanism in tissue repair seems to be related to their paracrine activity. BMSCs derived extracellular vesicles (BMSC-EVs), including mcirovesicles and exosomes, containing diverse proteins, mRNAs and micro-RNAs, mediating various biological functions, might be a main paracrine mechanism for stem cell to injured cell communication. We aimed to investigate the potential alleviating effects of BMSC-EVs in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis model. Intravenous injection of BMSC-EVs attenuated the severity of colitis as evidenced by decrease of disease activity index (DAI) and histological colonic damage. In inflammation response, the BMSC-EVs treatment significantly reduced both the mRNA and protein levels of nuclear factor kappaBp65 (NF-κBp65), tumor necrosis factor-alpha (TNF-α), induciblenitric oxidesynthase (iNOS) and cyclooxygenase-2 (COX-2) in injured colon. Additionally, the BMSC-EVs injection resulted in a markedly decrease in interleukin-1β (IL-1β) and an increase in interleukin-10 (IL-10) expression. Therapeutic effect of BMSC-EVs associated with suppression of oxidative perturbations was manifested by a decrease in the activity of myeloperoxidase (MPO) and Malondialdehyde (MDA), as well as an increase in superoxide dismutase (SOD) and glutathione (GSH). BMSC-EVs also suppressed the apoptosis via reducing the cleavage of caspase-3, caspase-8 and caspase-9 in colitis rats. Data obtained indicated that the beneficial effects of BMSC-EVs were due to the down regulation of pro-inflammatory cytokines levels, inhibition of NF-κBp65 signal transduction pathways, modulation of anti-oxidant/ oxidant balance, and moderation of the occurrence of apoptosis.

Oxymatrine improves TNBS-induced colitis in rats by inhibiting the expression of NF-κB p65

SummaryInflammatory bowel disease is thought to be regulated by the balance between Th1 and Th2 cytokines secreted by T cells, and NF-κB p65 also plays a predominant role in the intestinal inflammation. We evaluated the potency of oxymatrine, one of active components of Sophora Root, in inhibiting the immune responses and inflammation in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. The inflammation was markedly ameliorated in the oxymatrine-treated rats. The level of IL-2 was increased and that of IL-10 was decreased in colon tissue in the rat model, which was reversed by the treatment of oxymatrine. Moreover, the elevated expression of NF-κB p65 in colon tissue in the model was also improved by oxymatrine treatment. Our results suggest that oxymatrine might be beneficial for the abnormal immune responses and inflammation by regulating the unbalance of Th1 and Th2 cytokines secretion and inhibiting the expression of NF-κB p65 in colon tissue.Inflammatory bowel disease is thought to be regulated by the balance between Th1 and Th2 cytokines secreted by T cells, and NF-κB p65 also plays a predominant role in the intestinal inflammation. We evaluated the potency of oxymatrine, one of active components of Sophora Root, in inhibiting the immune responses and inflammation in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. The inflammation was markedly ameliorated in the oxymatrine-treated rats. The level of IL-2 was increased and that of IL-10 was decreased in colon tissue in the rat model, which was reversed by the treatment of oxymatrine. Moreover, the elevated expression of NF-κB p65 in colon tissue in the model was also improved by oxymatrine treatment. Our results suggest that oxymatrine might be beneficial for the abnormal immune responses and inflammation by regulating the unbalance of Th1 and Th2 cytokines secretion and inhibiting the expression of NF-κB p65 in colon tissue.

Over-expression of CXCR4 on mesenchymal stem cells protect against experimental colitis via immunomodulatory functions in impaired tissue

Bone marrow-derived mesenchymal stem cells (BMSCs) are attractive candidates for tissue regeneration and immunoregulation in inflammatory bowel disease. However, their in vivo reparative capability is limited owing to barren efficiency of BMSCs to injury region. Stromal cell-derived factor (SDF-1) plays an important role in chemotaxis and stem cell homing through interaction with its specific receptor CXC chemokine receptor 4 (CXCR4). The present study was designed to investigate the role of SDF-1α/CXCR4 axis in the therapeutic effects of lentivirus-preconditioned BMSCs for 2,4,6-trinitrobenzene sulfonic acid (TNBS)-colitis rats. BMSCs were isolated from female Sprague–Dawley rats and identified by flow cytometry. Lentiviral transduction was applied to over-express CXCR4/GFP (Ad-CXCR4-BMSCs) or null/GFP (Ad-GFP-BMSCs). Efficacy of engraftment was determined by the presence of enhanced green fluorescent protein (GFP) positive cells. One week after intravenous administration, Ad-GFP-BMSCs failed to colonize in the inflamed colon and had no beneficial effect in TNBS-induced colitis. Instead, Ad-CXCR4-BMSCs signally ameliorated both clinical and microanatomical severity of colitis. Immunofluorescence and western blotting showed that Ad-CXCR4-BMSCs migrated toward inflamed colon was more efficient than Ad-GFP-BMSCs. The therapeutic effect of Ad-CXCR4-BMSCs was mediated by the suppression of pro-inflammatory cytokines and STAT3 phosphorylation in injured colon. Collectively, our data indicated that over-expression CXCR4 led to enhance in vivo mobilization and engraftment of BMSCs into inflamed colon where these cells can function as an anti-inflammatory and immunomodulatory component of the immune system in TNBS-induced colitis.

miR-200b-containing microvesicles attenuate experimental colitis associated intestinal fibrosis by inhibiting epithelial-mesenchymal transition: miR-200b attenuates intestinal fibrosis

Epithelial–mesenchymal transition (EMT), characterized by the decrease of E‐cadherin (E‐Cad) and increase in vimentin and alpha‐smooth muscle actin (α‐SMA), was demonstrated to participate in inflammatory bowel disease‐related fibrosis. miR‐200b plays an anti‐fibrosis role in inhibiting EMT by targeting ZEB1 and ZEB2. But the stability of exogenous miR‐200b in blood limits its application. Microvesicles (MVs), which can transfer miRNAs among cells and prevent them from degradation, may provide an excellent transport system for the delivery of miR‐200b in the treatment of fibrosis.

Microvesicles Shuttled miR-200b attenuate Experimental Colitis associated Intestinal Fibrosis by Inhibiting the Development of EMT

Epithelial–mesenchymal transition (EMT), characterized by the decrease of E‐cadherin (E‐Cad) and increase in vimentin and alpha‐smooth muscle actin (α‐SMA), was demonstrated to participate in inflammatory bowel disease‐related fibrosis. miR‐200b plays an anti‐fibrosis role in inhibiting EMT by targeting ZEB1 and ZEB2. But the stability of exogenous miR‐200b in blood limits its application. Microvesicles (MVs), which can transfer miRNAs among cells and prevent them from degradation, may provide an excellent transport system for the delivery of miR‐200b in the treatment of fibrosis.

Intervention effects of QRZSLXF, a Chinese medicinal herb recipe, on the DOR-β-arrestin1-Bcl2 signal transduction pathway in a rat model of ulcerative colitis.

ETHNOPHARMACOLOGICAL RELEVANCE Qingre Zaoshi Liangxue Fang (QRZSLXF) is a Chinese medicinal herb recipe that is commonly prescribed for the treatment of ulcerative colitis. It includes 5 quality assured herbs: Sophora flavescens Aiton., Baphicacanthus cusia (Nees) Bremek., Bletilla striata Rchb.f., Glycyrrhiza uralensis Fisch. and Coptis chinensis Franch. The main phytochemical ingredient of QRZSLXF includes ammothamnine, sophocarpidine, liquiritin, berberine and indirubin. QRZSLXF has been clinically proven for use in the treatment of ulcerative colitis for over twenty years. In the past ten years, research has confirmed the therapeutic effect of QRZSLXF in ulcerative colitis and partially revealed its mechanism of action. Here, we further reveal the therapeutic mechanism of QRZSLXF in ulcerative colitis. To investigate the role of the DOR-β-arrestin1-Bcl-2 signal transduction pathway in ulcerative colitis and to determine the effects of QRZSLXF on this signal transduction pathway. MATERIALS AND METHODS Eighty-four Sprague-Dawley rats were randomly divided into six groups: normal control group, model group, mesalazine group, and QRZSLXF high-dose, medium-dose group and low-dose groups (n=14). Experimental colitis was induced by trinitrobenzenesulfonic acid (TNBS) in each group, except the normal control group. After modeling, bloody stool, mental state and diarrhea were observed and recorded. Two rats were randomly selected from the model groups adfnd sacrificed on day 3 to observe pathological changes in the colon tissue by microscopy. The rats in the QRZSLXF-treated groups received intramuscular injections of different concentrations of QRZSLXF for 15 days. The rats in the mesalazine group were treated with mesalazine solution (0.5 g/kg/day) by gastric lavage for 15 days. The rats in the normal control group and the model group were treated with 3 mL water by gastric lavage for 15 days. On the 16th day, after fasting for 24 h, the remaining rats were sacrificed and their colon tissues were used to detect the mRNA and protein expressions of DOR, β-arrestin1 and Bcl-2 by Real-time PCR and immunohistochemistry, respectively. Histological changes in the colon tissues were also examined. RESULTS AND CONCLUSIONS The expressions of DOR, β-arrestin1 and Bcl-2 were significantly different among the four groups. The expressions of DOR, β-arrestin1 and Bcl-2 protein and mRNA were significantly increased in the model group compared with the other groups (P<0.05). In contrast to the model group, the expressions of DOR, β-arrestin1 and Bcl-2 were significantly decreased in the mesalazine group and the groups that received different doses of QRZSLXF (P<0.05), and there were no statistically significant differences among the mesalazine and QRZSLXF-treated groups (P>0.05). This study indicates that the DOR-beta-arrestin1-Bcl-2 signal transduction pathway may participate in the pathologic course of ulcerative colitis. Moreover, QRZSLXF could attenuate ulcerative colitis by regulating the DOR-β-arrestin1-Bcl-2 signal transduction pathway.

Effect of Wumeiwan on Cytokines TNF-α, IL-6, IL-8, IL-10 and Expression of NF-κBp65 in Rats with Ulcerative Colitis

SummaryThe effects of Wumeiwan (WMW) on TNF-α, IL-6, IL-8, IL-10 and NF-κBp65 in rats with ulcerative colitis (UC) were investigated, the curative effectiveness of WMW vs salicylazosulfapyridine (SASP) was compared, and the action mechanism was analyzed. Fifty-Six Sprague-Dawley (SD) rats were randomly divided into four groups (n=14 in each group, with equal ratio of male and female): normal control group, model group, SASP group, and WMW group. Except normal control group, the rat UC models in the remaining three groups were established using the method of 2.4-dinitrochlorobenzene (DNCB) immunization and acetic acid local enema. The rats in model group, SASP group, and WMW group were treated with distilled water, SASP, and WMW respectively. The changes in the symptoms and signs were observed, and levels of IL-6, IL-8, TNF-α, IL-10 and the expression of NF-κBp65 in the colonic tissues were statistically analyzed. The results showed that the levels of IL-6, IL-8, and TNF-α were significantly increased (P<0.01), while those of IL-10 significantly reduced (P<0.01) after establishment of rat UC models as compared with normal control group. The levels of IL-6, IL-8, and TNF-α were obviously lower, but the level of IL-10 was obviously higher in WMW and SASP groups than those in model group (P<0.05). The levels of IL-6, IL-8, and TNF-α were lower, while the level of IL-10 was higher in WMW group than in SASP group. NF-κBp65 was expressed negatively or weakly in normal colonic tissues. The positive expression rate of NF-κBp65 in WMW group and SASP group was obviously lower than in model group (P<0.01), and there was significant difference between WMW group and SASP group (P<0.05). It was concluded that rat UC model was established successfully. WMW could up-regulate the expression of IL-10, down-regulate the expression of TNF-α, IL-6, IL-8, and inhibit the NF-κBp65 activity to adjust immune function, indicating WMW had better curative effects on UC in rats.The effects of Wumeiwan (WMW) on TNF-α, IL-6, IL-8, IL-10 and NF-κBp65 in rats with ulcerative colitis (UC) were investigated, the curative effectiveness of WMW vs salicylazosulfapyridine (SASP) was compared, and the action mechanism was analyzed. Fifty-Six Sprague-Dawley (SD) rats were randomly divided into four groups (n=14 in each group, with equal ratio of male and female): normal control group, model group, SASP group, and WMW group. Except normal control group, the rat UC models in the remaining three groups were established using the method of 2.4-dinitrochlorobenzene (DNCB) immunization and acetic acid local enema. The rats in model group, SASP group, and WMW group were treated with distilled water, SASP, and WMW respectively. The changes in the symptoms and signs were observed, and levels of IL-6, IL-8, TNF-α, IL-10 and the expression of NF-κBp65 in the colonic tissues were statistically analyzed. The results showed that the levels of IL-6, IL-8, and TNF-α were significantly increased (P<0.01), while those of IL-10 significantly reduced (P<0.01) after establishment of rat UC models as compared with normal control group. The levels of IL-6, IL-8, and TNF-α were obviously lower, but the level of IL-10 was obviously higher in WMW and SASP groups than those in model group (P<0.05). The levels of IL-6, IL-8, and TNF-α were lower, while the level of IL-10 was higher in WMW group than in SASP group. NF-κBp65 was expressed negatively or weakly in normal colonic tissues. The positive expression rate of NF-κBp65 in WMW group and SASP group was obviously lower than in model group (P<0.01), and there was significant difference between WMW group and SASP group (P<0.05). It was concluded that rat UC model was established successfully. WMW could up-regulate the expression of IL-10, down-regulate the expression of TNF-α, IL-6, IL-8, and inhibit the NF-κBp65 activity to adjust immune function, indicating WMW had better curative effects on UC in rats.

Modulation of nuclear factor-κB-mediated pro-inflammatory response is associated with exogenous administration of bone marrow-derived mesenchymal stem cells for treatment of experimental colitis.

Mesenchymal stem cells (MSCs) inhibit the immune response in vitro and prevent the induction of disease in certain experimental models. As a result, MSC‑mediated therapy is a rapidly growing field of research. However, the efficacy of MSCs in the treatment of inflammatory bowel disease (IBD) has remained to be determined. In the present study, rats with 2,4,6‑trinitrobenzene sulfonic acid (TNBS)‑induced colitis were injected with prepared MSCs (1x106) into the tail vein. Two weeks following intravenous MSC administration, the concentration of tumor necrosis factor‑α (TNF‑α) in the serum was measured by an ELISA. The protein expression of nuclear factor‑κB (NF‑κBp65) in the colonic mucosa was assessed by western blot analysis. mRNA expression of TNF‑α and NF‑κBp65 was determined by reverse‑transcription quantitative polymerase chain reaction. MSCs were shown to exert an immunomodulatory effect on TNBS‑induced colitis and may be of use in the treatment of IBD. In addition, modulation of the NF‑κB‑mediated pro‑inflammatory response may contribute to the underlying mechanism by which MSCs ameliorate the clinical and histological changes associated with IBD.

The role of STAT3 and AhR in the differentiation of CD4+ T cells into Th17 and Treg cells

Background: This study aimed to investigate the role of aryl hydrocarbon receptor (AhR) and STAT3 gene during the differentiation of cluster of differentiation (CD)4+ T cells into T helper (Th)17 and T regulatory (Treg) cells. Methods: First, CD4+ T cells were isolated from the spleen of BALB/c mice. Then, stable CD4+ T cells expressing STAT3 shRNA were constructed. CD4+ T cells were assigned to one of the following treatments: Th17 group: antibodies against CD3 and CD28, 2.5 ng/mL transforming growth factor &bgr; (TGF-&bgr;)1, 30 ng/mL interleukin (IL)-6, and 30 ng/mL IL-23; 6-formylindolo[3,2-b]carbazole (FICZ) group: antibodies against CD3 and CD28, 2.5 ng/mL TGF-&bgr;1, 30 ng/mL IL-6, 30 ng/mL IL-23, and 100 nM FICZ; FICZ + STAT3 RNAi group (shSTAT3 group): antibodies against CD3 and CD28, 2.5 ng/mL TGF-&bgr;1, 30 ng/mL IL-6, 30 ng/mL IL-23, 100 nM FICZ, and STAT3 RNAi; naphthoflavone group: antibodies against CD3 and CD28, 2.5 ng/mL TGF-&bgr;1, 30 ng/mL IL-6, 30 ng/mL IL-23, and 3 &mgr;M naphthoflavone; 5) no antibodies were added in the control group. Later, the proportions of Th17 and Treg cells in each group were measured by flow cytometry; phospho-STAT3 and -STAT5 levels were measured by western blotting; and AhR, STAT3, STAT5, receptor-related orphan nuclear receptor &ggr;t (ROR&ggr;t), FOXP3, T-cell receptor (TCR), CD25, IL-6R, IL-10, and IL-17 mRNA levels were also measured by real-time PCR. Result: Th17 cells showed a rise and Treg cells showed a decrease in the FICZ group, but revised in the shSTAT3 group and the naphthoflavone group. Significant differences were observed in CD25, IL-6R, IL-10, and IL-17 mRNA levels among different groups. Conclusion: STAT3 may cooperate with AhR to regulate the differentiation of both Th17 and Treg cells.

Oxymatrine protects against DSS-induced colitis via inhibiting the PI3K/AKT signaling pathway.

Abstract Oxymatrine (OMT), an alkaloid derived from the root of the Sophora flavescens, has been reported to possess a significant effect on relieving UC owing to its anti‐inflammatory property. But the other therapeutic mechanism of OMT remains unclear. Recent studies have found, PI3K/AKT signaling pathway is involved in the pathogenesis of UC by pro‐inflammatory effects and activating T cells. Moreover, PI3K/AKT pathway is one of the most important pathways for regulating cell apoptosis. Thus, we aim to explore whether OMT protects against UC by targeting PI3K/AKT pathway. We established the UC mice models, using LY294002 (a specific inhibitor of PI3K/AKT) as a positive control, to observe the effect of low, medium and high dose of OMT on UC and its influence on PI3K/AKT signaling pathway. Our data indicated that OMT can significantly ameliorate UC through anti‐inflammatory, pro‐apoptotic, down‐regulating the differentiation of Th1 and Th17 cells via PI3K/AKT pathway. This study reveals that PI3K/AKT signaling pathway is a potential mechanism of OMT‐induced UC remission and suggests that OMT is a promising therapeutic agent for the treatment of UC. Graphical abstract Figure. No Caption available. HighlightsOxymatrine alleviates UC through regulating inflammation, apoptosis and immunity.PI3K/AKT signaling pathway mediates the pathogenesis of UC.Oxymatrine ameliorates UC by suppressing PI3K/AKT activation.