MiR-155 inhibition ameliorates 2, 4, 6-Trinitrobenzenesulfonic acid (TNBS)-induced experimental colitis in rat via influencing the differentiation of Th17 cells by Jarid2

MiRNA-Based Therapies for the Treatment of Inflammatory Bowel Disease: What Are We Still Missing?

Micro-RNAs (miRNAs) are noncoding RNAs usually 24-30 nucleotides long that play a central role in epigenetic mechanisms of inflammatory diseases and cancers. Recently, several studies have assessed the involvement of miRNAs in the pathogenesis of inflammatory bowel disease (IBD) and colitis-associated neoplasia. Particularly, it has been shown that many members of miRNAs family are involved in the pathways of inflammation and fibrogenesis of IBD; therefore, their use as inflammatory and fibrosis biomarkers has been postulated. In light of these results, the role of miRNAs in IBD therapy has been proposed and is currently under investigation with many in vitro and in vivo studies, murine models, and a phase 2a trial. The accumulating data have pushed miRNA-based therapy closer to clinical practice, although many open questions remain. With this systematic review, we discuss the current knowledge about the therapeutic effects of miRNAs mimicking and inhibition, and we explore the new potential targets of miRNA family for the treatment of inflammation and fibrosis in IBD.

New progress in research of Th17 cells and related cytokines in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic non-specific intestinal inflammatory disease. IBD is an immune disease, and there is no cure for it at present. Intestinal immunity is the research focus of IBD. Focusing on Th17 cells and related cytokines, this article reviews the updated research on IBD, including its etiology, its relationship with adaptive immunity, and its relationship with Th17 cells. We also introduce Th17 cells and related cytokines, and their research in IBD. Finally, we point out the future research direction of Th17 cells in IBD.

LncRNA GAS5 participates in childhood pneumonia by inhibiting cell apoptosis and promoting SHIP-1 expression via downregulating miR-155

Background

LncRNA GAS5 and miR-155 are reported to play opposite roles in lung inflammatory responses. Lung inflammation participates in childhood pneumonia, indicating the involvement of GAS5 and miR-155 in pneumonia. The study aimed to analyze the potential interaction between GAS5 and miR-155 in childhood pneumonia.

Methods

GAS5 and miR-155 levels in plasma samples from pneumonia patients and controls were detected using RT-qPCR. The role of GAS5 in miR-155 RNA gene methylation in human bronchial epithelial cells (HBEpCs) was analyzed by methylation analysis. Flow cytometry and RT-qPCR were applied to analyze cell apoptosis and SHIP-1 expression, respectively.

Results

GAS5 was downregulated in pneumonia, and miR-155 was upregulated in pneumonia. GAS5 and miR-155 were inversely correlated. GAS5 overexpression decreased miR-155 expression in HBEpCs, while miR-155 overexpression showed no significant effects on GAS5 expression. In addition, GAS5 suppressed LPS-induced HBEpC apoptosis, promoted SHIP-1 expression, and reduced the enhancing effect of miR-155 on cell apoptosis and SHIP-1 expression.

Conclusions

GAS5 may participate in childhood pneumonia by inhibiting cell apoptosis and promoting SHIP-1 expression via downregulating miR-155.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01724-y.

miRNA-Based Potential Biomarkers and New Molecular Insights in Ulcerative Colitis

Ulcerative colitis (UC) is a chronic non-specific inflammatory bowel disease, which usually manifests as abdominal pain, diarrhea and hematochezia. The disease often recurs and is difficult to cure. At present, the pathogenesis is not clear, but it is believed that the disease is caused by a complex interaction among immunity, heredity, environment and intestinal microflora disorders. MicroRNA (miRNA) is endogenous single-stranded non-coding RNA of 17–25 nucleotides (nts). They target the 3'Untranslated Region of a target gene and inhibit or degrade the target gene according to the extent of complementary bases. As important gene expression regulators, miRNAs are involved in regulating the expression of most human genes, and play an important role in the pathogenesis of many autoimmune diseases including UC. Studies in recent years have illustrated that abnormal expression of miRNA occurs very early in disease pathogenesis. Moreover, this abnormal expression is highly related to disease activity of UC and colitis-associated cancer, and involves virtually all key UC-related mechanisms, such as immunity and intestinal microbiota dysregulation. Recently, it was discovered that miRNA is highly stable outside the cell in the form of microvesicles, exosomes or apoptotic vesicles, which raises the possibility that miRNA may serve as a novel diagnostic marker for UC. In this review, we summarize the biosynthetic pathway and the function of miRNA, and summarize the usefulness of miRNA for diagnosis, monitoring and prognosis of UC. Then, we described four types of miRNAs involved in regulating the mechanisms of UC occurrence and development: 1) miRNAs are involved in regulating immune cells; 2) affect the intestinal epithelial cells barrier; 3) regulate the homeostasis between gut microbiota and the host; and 4) participate in the formation of tumor in UC. Altogether, we aim to emphasize the close relationship between miRNA and UC as well as to propose that the field has value for developing potential biomarkers as well as therapeutic targets for UC.

Mastiha has efficacy in immune-mediated inflammatory diseases through a microRNA-155 Th17 dependent action

Mastiha is a natural nutritional supplement with known anti-inflammatory properties. Non-alcoholic fatty liver disease (NAFLD) and Inflammatory bowel disease (IBD) are immune mediated inflammatory diseases that share common pathophysiological features. Mastiha has shown beneficial effects in both diseases. MicroRNAs have emerged as key regulators of inflammation and their modulation by phytochemicals have been extensively studied over the last years. Therefore, the aim of this study was to investigate whether a common route exists in the anti-inflammatory activity of Mastiha, specifically through the regulation of miRNA levels. Plasma miR-16, miR-21 and miR-155 were measured by Real-Time PCR before and after two double blinded and placebo-controlled randomized clinical trials with Mastiha. In IBD and particularly in ulcerative colitis patients in relapse, miR-155 increased in the placebo group (p = 0.054) whereas this increase was prevented by Mastiha. The mean changes were different in the two groups even after adjusting for age, sex and BMI (p = 0.024 for IBD and p = 0.042). Although the results were not so prominent in NAFLD, miR-155 displayed a downward trend in the placebo group (p = 0.054) whereas the levels did not changed significantly in the Mastiha group in patients with less advanced fibrosis. Our results propose a regulatory role for Mastiha in circulating levels of miR-155, a critical player in T helper-17 (Th17) differentiation and function.

Propofol Regulates the TLR4/NF-κB Pathway Through miRNA-155 to Protect Colorectal Cancer Intestinal Barrier

Surgery for colorectal cancer (CRC) can cause damage to the intestinal mucosal barrier and lead to bacterial invasion. This study mainly analyzed whether propofol (PPF) could protect the intestinal mucosal barrier damage caused by CRC surgery, and explored its molecular mechanism. A mouse CRC model was constructed using azomethane and dextran sulfate sodium. During anesthesia, continuous intravenous injection of PPF was used for intervention. The influences of PPF on intestinal mucosal permeability and bacterial invasion were detected. The levels of microRNA (miR)-155, Toll-like receptor 4 (TLR4)/NF-κB in the intestinal mucosa, and the location of miR-155 were detected by fluorescence in situ hybridization (FISH). Mouse macrophages were used to analyze the regulation of miR-155 on the secretion of inflammatory cytokines through the TLR4/NF-κB pathway. PPF treatment promoted the expression of tight junction protein in the intestinal mucosa, protected the intestinal barrier, inhibited the translocation of intestinal bacteria, and increased the level of the beneficial bacterium Lactobacillus on the mucosal surface. In addition, PPF treatment could inhibit the expression of miR-155, TLR4/NF-KB, and reverse inflammatory response. miR-155 was expressed in macrophages of intestinal mucosa tissue. Overexpression of miR-155 promoted the nuclear translocation of NF-κB and the expression of inflammatory cytokines in macrophages. The use of VIPER to inhibit TLR4 reversed the pro-inflammatory effects of miR-155. PPF might inhibit the activation of the NF-κB pathway by downregulating miR-155 expression, thereby reducing the secretion of inflammatory cytokines. This might be the mechanism by which PPF protected the intestinal barrier of CRC surgical model mice.

Compound Sophorae Decoction: treating ulcerative colitis by affecting multiple metabolic pathways

Ulcerative colitis (UC) is a chronic refractory non-specific intestinal inflammatory disease that is difficult to be cured. The discovery of new ulcerative colitis-related metabolite biomarkers may help further understand UC and facilitate early diagnosis. It may also provide a basis for explaining the mechanism of drug action in the treatment of UC. Compound Sophorae Decoction (CSD) is an empirical formula used in the clinical treatment of UC. Although it is known to be efficacious, its mechanism of action in the treatment of UC is unclear. The purpose of this study was to investigate the changes in endogenous substances in UC rats and the effects of CSD on metabolic pathways using the metabonomics approach. Metabolomics studies in rats with UC and normal rats were performed using LC-MS/MS. Rats with UC induced using TNBS enema were used as the study models. Metabolic profiling and pathway analysis of biomarkers was performed using statistical and pathway enrichment analyses. 36 screened potential biomarkers were found to be significantly different between the UC and the normal groups; it was also found that CSD could modulate the levels of these potential biomarkers. CSD was found to be efficacious in UC by regulating multiple metabolic pathways.

MiR-155 contributes to intestinal barrier dysfunction in DSS-induced mice colitis via targeting HIF-1α/TFF-3 axis

Intestinal barrier dysfunction is a hallmark of inflammatory bowel disease (IBD). MiR-155 is increased in colitis and downregulates expression of hypoxia-inducible factor 1α (HIF-1α). Here, we investigated the effects of miR-155 on intestinal barrier dysfunction in dextran sulfate sodium (DSS)-induced colitis. We found that miR-155 antagomir treatment relieved weight loss and intestinal damage in IBD mouse models (P < 0.05). Furthermore, electron microscopy and immunofluorescence imaging showed that miR-155 increased intestinal barrier dysfunction and downregulated the expression of tight junction proteins in DSS-induced colitis. FG-4497, which upregulates HIF-1α expression, elicited protective effects on the intestinal barrier in DSS-induced colitis. Dual luciferase reporter assays also confirmed that miR-155 downregulated expression of HIF-1α. Finally, we discovered that HIF-1α levels were elevated by miR-155 antagomir treatment (P < 0.05) and that TFF-3 expression correlated positively with HIF-1α expression. These results suggest that miR-155 contributes to DSS-induced colitis by promoting intestinal barrier dysfunction and inhibiting the HIF-1α/TFF-3 axis.

Serum Biomarkers for Inflammatory Bowel Disease

Background: Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, is a chronic, inflammatory disorder of the gastrointestinal tract. As the novel therapeutic goal and biologicals are widely recognized, accurate assessment of disease and prediction of therapeutic response have become a crucial challenge in clinical practice. Also, because of the continuously rising incidence, convenient and economical methods of diagnosis and clinical assessment are urgently needed. Recently, serum biomarkers have made a great progress and become a focus in IBD study because they are non-invasive, convenient, and relatively inexpensive than are markers in biopsy tissue, stool, breath, and other body fluids.

Aims: To review the available data on serological biomarkers for IBD.

Methods: We searched PubMed using predefined key words on relevant literatures of serum biomarkers regarding diagnosis, evaluation of therapeutic efficacy, surveillance of disease activity, and assessment of prognosis for IBD.

Results: We reviewed serological biomarkers that are well-established and widely used (e.g., C-reactive protein), newly discovered biomarkers (e.g., cytokines, antibodies, and non-coding RNAs), and also recently advancements in serological biomarkers (e.g., metabolomics and proteomics) that are used in different aspects of IBD management.

Conclusions: With such a wealth of researches, to date, there are still no ideal serum biomarkers for IBD. Serum profiling and non-coding RNAs are just starting to blossom but reveal great promise for future clinical practice. Combining different biomarkers can be valuable in improving performance of disease evaluation.

Effects of Inhibition of miR-155-5p in Neural Stem Cell Subarachnoid Transplant on Rats with Cerebral Infarction

Cerebral infarction is a leading cause of death, which calls for effective prevention and treatment. Transplant of neural stem cells (NSCs) is a potential therapeutic treatment to cerebral infarction although its efficacy still needs to be improved. Overexpression of hypoxia-inducible factor 1α (HIF-1α) has been shown to enhance the protective effects of stem cell transplant on cerebral infarction. The expression of HIF-1α is predicted to be regulated by miR-155-5p. Therefore, we regulated the expression of miR-155-5p in NSCs and evaluated the effects of miR-155-5p-regulated NSC transplant on cerebral infarction. We inhibited miR-155-5p expression in NSCs by overexpressing miR-155-5p inhibitor. HIF-1α expression, cell viability, and the expression of apoptosis markers were examined. We established the middle cerebral artery occlusion (MCAO) rat model, and the infarct volume, neurobehavioral outcomes, inflammation, and oxidative stress were evaluated after NSC transplant. miR-155-5p directly targeted HIF-1α and negatively regulated its expression. Inhibition of miR-155-5p enhanced cell viability and prevented cell apoptosis. Transplant of miR-155-5p-inhibited NSCs significantly decreased infarct volume and improved neurobehavioral outcomes of MCAO rats. Transplant of miR-155-5p-inhibited NSCs significantly inhibited inflammation and oxidative stress. Inhibition of miR-155-5p in NSCs resulted in enhanced protection against cerebral infarction after NSC transplant.

miR-155 antagomir protect against DSS-induced colitis in mice through regulating Th17/Treg cell balance by Jarid2/Wnt/β-catenin

BACKGROUND

Th subsets particularly T helper 17 and regulatory T cells play a critical role in immune balance in colonic mucosa of Inflammatory Bowel Disease. Recent studies have indicated miR-155 is overexpressed in the colonic mucosa in IBD patients. Thus, whether and how miR-155 influences Th17/Treg cell balance in IBD patients is worthy of researching.

METHODS

We divided mice into four groups: the mice oral administration of 3.0 % DSS in fresh drinking water for 7 days except normal group. In this period, starting from the fifth day, the miR-155 and NC antagomir group were carried out by intraperitoneal injection of miR-155 antagomirs and corresponding negative controls. In vitro, we isolated naïve CD4⁺T cells and divided into two groups: the cells were transfected with mmu-miR-155-5p inhibitor or corresponding negative controls and then induced differentiation.

RESULTS

We found miR-155 antagomir can reach colon tissues in DSS-induced colitis and indeed ameliorated DSS-induced experimental colitis. Subsequently, we proved the levels of Th17 cells in spleens and Mesenteric lymph nodes and its associated IL-6, IL-17A and RORγt in colonic tissues were dramatically decreased and TGF-β1 raised in DSS + miR-155 antagomir group. However, miR-155 antagomir significantly increased the expression of Tregs. In vitro, we found miR-155 inhibitor could improve the Tregs but decrease Th17 cells. Finally, we dig out that Jarid2 was apparently improved by miR-155 antagomir, Wnt/β-catenin and its associated T cell factor-4 (TCF-4) and Cyclin D1 expression were positively correlated with Jarid2.

CONCLUSION

Silencing of miR-155 attenuates DSS-induced colitis by regulating Th17/Treg cell balance and Jarid2/Wnt/β-catenin participated in the process.

MicroRNA-219a-5p suppresses intestinal inflammation through inhibiting Th1/Th17-mediated immune responses in inflammatory bowel disease

MicroRNA (miR)-219a-5p has been implicated in the development of numerous progression of carcinoma and autoimmune diseases. However, whether miR-219a-5p is involved in the pathogenesis of inflammatory bowel disease (IBD) remains elusive. In this study, we demonstrated that miR-219a-5p expression was significantly decreased in the inflamed intestinal mucosa and peripheral blood (PB)-CD4⁺ T cells from patients with IBD. Proinflammatory cytokines (e.g., IL-6, IL-12, IL-23 and TNF-α) inhibited miR-219a-5p expression in CD4⁺ T cells in vitro. Lentivirus-mediated miR-219a-5p downregulation facilitated Th1/Th17 cell differentiation, whereas miR-219a-5p overexpression exerted an opposite effect. Luciferase assays confirmed that ETS variant 5 (ETV5) was a functional target of miR-219a-5p and ETV5 expression was significantly increased in the inflamed intestinal mucosa and PB-CD4⁺ T cells from IBD patients. ETV5 overexpression enhanced Th1/Th17 immune response through upregulating the phosphorylation of STAT3 and STAT4. Importantly, supplementation of miR-219a-5p ameliorated TNBS-induced intestinal mucosal inflammation, characterized by decreased IFN-γ⁺ CD4⁺ T cells and IL-17A⁺ CD4⁺ T cells infiltration in the colonic lamina propria. Our data thus reveal a novel mechanism whereby miR-219a-5p suppresses intestinal inflammation through inhibiting Th1/Th17-mediated immune responses. miR-219a-5p might be a target for the treatment of IBD.

Role of miR-155 in pathogenesis of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a non-infectious, non-specific intestinal inflammatory disease, and its incidence is increasing year by year. A better understanding of the pathogenesis of IBD can help to find more suitable treatment methods for this disease. Recently, a large number of studies have shown that miR-155 plays an important role in the pathogenesis of IBD. It can regulate TH17 differentiation through the Jarid2/notch1 signaling pathway and by regulating type 2 macrophage differentiation. It also regulates T-regulatory cells by inhibiting cytotoxic T lymphocyte-associated antigen-4; intestinal myelofibrosis through suppressor of cytokine signaling 1; and DNA double-strand break deposition to affect intestinal inflammation. This article reviews the immune mechanism of action of miR-155 in IBD.