Levels Of microRNA-155 Research Articles

Correlations Between the Expression of MicroRNA-155 and Suppressor of Cytokine Signaling 1 in Colonic Mucosal Tissue and Disease Severity in Patients With Ulcerative Colitis

Objective To explore the relationship between the expression levels of microRNA-155 (miR-155) and suppressor of cytokine signaling 1 (SOCS1) in the colonic mucosal tissue of patients with ulcerative colitis (UC) and the severity of the disease.Methods A total of 130 UC patients admitted to the Second Affiliated Hospital of Hebei North University from September 2021 to June 2023 were selected.According to the modified Mayo score system,the patients were assigned into an active stage group (n=85) and a remission stage group (n=45).According to the modified Truelove and Witts classification criteria,the UC patients at the active stage were assigned into a mild group (n=35),a moderate group (n=30),and a severe group (n=20).A total of 90 healthy individuals who underwent colonoscopy for physical examination or those who had normal colonoscopy results after single polypectomy and excluded other diseases were selected as the control group.The colonic mucosal tissues of UC patients with obvious lesions and the colonic mucosal tissue 20 cm away from the anus of the control group were collected.The levels of miR-155 and SOCS1 mRNA in tissues were determined by fluorescence quantitative PCR,and the expression of SOCS1 protein in tissues was determined by immunohistochemistry.The correlations of the levels of miR-155 and SOCS1 mRNA in the colonic mucosal tissue with the modified Mayo score of UC patients were analyzed.The values of the levels of miR-155 and SOCS1 mRNA in predicting the occurrence of severe illness in the UC patients at the active stage were evaluated.Results Compared with the control group and the remission stage group,the active stage group showed up-regulated expression level of miR-155,down-regulated level of SOCS1 mRNA,and decreased positive rate of SOCS1 protein in the colonic mucosal tissue (all P<0.001).The expression level of miR-155 and modified Mayo score in colonic mucosal tissues of UC patients at the active stage increased,while the mRNA level of SOCS1 was down-regulated as the disease evolved from being mild to severe (all P<0.001).The modified Mayo score was positively correlated with the miR-155 level and negative correlated with the mRNA level of SOCS1 in colonic mucosal tissues of UC patients (all P<0.001).The high miR-155 level (OR=2.762,95%CI=1.284-5.944,P=0.009),low mRNA level of SOCS1 (OR=2.617,95%CI=1.302-5.258,P=0.007),and modified Mayo score≥12 points (OR=3.232,95%CI=1.450-7.204,P=0.004) were all risk factors for severe disease in the UC patients at the active stage.The area under curve of miR-155 combined with SOCS1 mRNA in predicting severe illness in the UC patients at the active stage was 0.920.Conclusions The expression levels of miR-155 and SOCS1 mRNA were correlated with the disease severity in the UC patients at the active stage.The combination of the two indicators demonstrates good performance in predicting the occurrence of severe illness in UC patients at the active stage.

A highly sensitive colorimetric DNA sensor for MicroRNA-155 detection: leveraging the peroxidase-like activity of copper nanoparticles in a double amplification strategy.

A novel and highly sensitive colorimetric DNA sensor for determination of miRNA-155at attomolar levelsis presentedthat combines the peroxidase-like activity of copper nanoparticles (CuNPs) with the hybridization chain reaction (HCR) . The utilization of CuNPs offers advantages such as strong interaction with double-stranded DNA, excellent molecular recognition, and mimic catalytic activity. Herein, a capture probe DNA (P1) was immobilized on carboxylated magnetic beads (MBs), allowing for amplified immobilization due to the 3D surface. Subsequently, the presence of the target microRNA-155 led to the formation of a sandwich structure (P2/microRNA-155/P1/MBs) when P2 was introduced to the modified P1/MBs. The HCR reaction was then triggered by adding H1 and H2 to create a super sandwich (H1/H2)n. Following this, Cu2+ ions were attracted to the negatively charged phosphate groups of the (H1/H2)n and reduced by ascorbic acid, resulting in the formation of CuNPs, which were embedded into the grooves of the (H1/H2)n. The peroxidase-like activity of CuNPs catalyzed the oxidation reaction of 3,3',5,5'-Tetramethylbenzidine (TMB), resulting in a distinct blue color measured at 630 nm. Under optimal conditions, the colorimetric biosensor exhibited a linear response to microRNA-155 concentrations ranging from 80 to 500 aM, with a detection limit of 22 aM, and discriminate against other microRNAs. It was also successfully applied to the determination of microRNA-155 levels in spiked human serum.

Matrine Protects Intestinal Barrier Function via MicroRNA-155 Through ROCK1-Signaling Pathway.

The aim of this study was to investigate the protective effects on intestinal barrier function and tight junction by matrine via a small, non-coding RNA microRNA-155-signaling pathway. Tight junction protein and target gene expressions were determined through microRNA-155 inhibition or overexpression of Caco-2 cell line with or without the treatment of matrine. In order to further verify the role of matrine, dextran sulfate sodium-induced mice colitis was treated by matrine. MicroRNA-155 and ROCK1 expressions were detected in clinical specimens of acute obstruction patients. Matrine could enhance the expression level of occludin, which might be inhibited by the overexpression of microRNA-155. After the transfection of the precursor of microRNA-155 into Caco-2 cells, ROCK1 expression was increased at both mRNA and protein levels. MicroRNA-155 inhibitor could decrease the ROCK1 expression after transfection. Furthermore, matrine could increase the permeability and decrease tight junction-associated proteins induced by dextran sulfate sodium-induced mice colitis. Clinical sample detection also found high levels of microRNA-155 in stercoral obstruction patients. Matrine could maintain the tight junction and protect the intestinal barrier from dysfunction. The molecular mechanism may be that matrine might inhibit microRNA-155 and increase the expression level of tight junction proteins.

MicroRNA-155 expression with Brucella infection in vitro and in vivo and decreased serum levels of MicroRNA-155 in patients with brucellosis

Infection with Brucella is characterized by the inhibition of host immune responses. MicroRNA-155 (miR-155) has been implicated in the immune response to many diseases. In this study, its expression during Brucella 16M infection of macrophages and mice was analyzed. Expression of miR-155 was significantly induced in macrophages at 24 h post infection. Further, an analysis of infected mice showed that miR-155 was inhibited at 7 and 14 days but induced at 28 days. Interestingly, this trend in induction or inhibition was reversed at 7 and 14 days in 16M△virB-infected mice. This suggested that decreased expression of miR-155 at an early stage of infection was dependent on intracellular replication. In humans with brucellosis, serum levels of miR-155 were significantly decreased compared to those in individuals without brucellosis and healthy volunteers. Significant correlations were observed between serum level of miR-155 and serum anti-Brucella antibody titers and the sweating symptom. This effect suggests that Brucella interferes with miR-155-regulated immune responses via a unique mechanism. Taken together, data from this study indicate that Brucella infection affects miR-155 expression and that human brucellosis patients show decreased serum levels of miR-155.

Altered Expression Levels of MicroRNA-155 and SOCS-1 in Peripheral Blood Mononuclear Cells of Newly Diagnosed Breast Cancer Patients

MicroRNA-155 (miR-155) has a critical role in pro-inflammatory activation and tumor progression. In addition, miR-155 has various oncogenic effects in the tumor microenvironment by targeting the suppressor gene of cytokine signaling-1(SOCS-1) and interleukin-6 (IL-6). This study investigated the association of inflammatory changes with the variations of miR-155 expression in newly diagnosed breast cancer (NDBC) patients. Seventy NDBC patients were categorized as lobular and ductal subgroups and forty healthy individuals participated in this study. The expression rate of miR-155 and its downstream target gene, SOCS-1, as well as the plasma levels of IL-6, were evaluated in peripheral blood mononuclear cells of NDBC patients; using real-time PCR and enzyme-linked immunosorbent assay, respectively. Our results indicated an over-expression of miR-155 in the PBMCs of NDBC patients which was significantly associated with the tumor grade and the type of ductal carcinoma. In contrast, a significant downregulation of SOCS-1 was observed in NDBC patients compared to control group, however, there was no significant difference between two subtypes of BC. Furthermore, a higher concentration of plasma IL-6 was detected in NDBC patients compared to the healthy control group which had an inverse correlation with the SOCS-1 levels. According to the potential effects of miR-155 on regulating the expression of SOCS-1 and IL-6, we suggest this small transcript as a promising diagnostic marker for various types of BC patients.

Endothelial-Derived Extracellular Vesicles Induce Cerebrovascular Dysfunction in Inflammation.

Blood–brain barrier (BBB) dysfunction is a key hallmark in the pathology of many neuroinflammatory disorders. Extracellular vesicles (EVs) are lipid membrane-enclosed carriers of molecular cargo that are involved in cell-to-cell communication. Circulating endothelial EVs are increased in the plasma of patients with neurological disorders, and immune cell-derived EVs are known to modulate cerebrovascular functions. However, little is known about whether brain endothelial cell (BEC)-derived EVs themselves contribute to BBB dysfunction. Human cerebral microvascular cells (hCMEC/D3) were treated with TNFα and IFNy, and the EVs were isolated and characterised. The effect of EVs on BBB transendothelial resistance (TEER) and leukocyte adhesion in hCMEC/D3 cells was measured by electric substrate cell-substrate impedance sensing and the flow-based T-cell adhesion assay. EV-induced molecular changes in recipient hCMEC/D3 cells were analysed by RT-qPCR and Western blotting. A stimulation of naïve hCMEC/D3 cells with small EVs (sEVs) reduced the TEER and increased the shear-resistant T-cell adhesion. The levels of microRNA-155, VCAM1 and ICAM1 were increased in sEV-treated hCMEC/D3 cells. Blocking the expression of VCAM1, but not of ICAM1, prevented sEV-mediated T-cell adhesion to brain endothelia. These results suggest that sEVs derived from inflamed BECs promote cerebrovascular dysfunction. These findings may provide new insights into the mechanisms involving neuroinflammatory disorders.

Reduced SOCS1 Expression in Lung Fibroblasts from Patients with IPF Is Not Mediated by Promoter Methylation or Mir155.

The interleukin (IL)-6 family of cytokines and exaggerated signal transducer and activator of transcription (STAT)3 signaling is implicated in idiopathic pulmonary fibrosis (IPF) pathogenesis, but the mechanisms regulating STAT3 expression and function are unknown. Suppressor of cytokine signaling (SOCS)1 and SOCS3 block STAT3, and low SOCS1 levels have been reported in IPF fibroblasts and shown to facilitate collagen production. Fibroblasts and lung tissue from IPF patients and controls were used to examine the mechanisms underlying SOCS1 down-regulation in IPF. A significant reduction in basal SOCS1 mRNA in IPF fibroblasts was confirmed. However, there was no difference in the kinetics of activation, and methylation of SOCS1 in control and IPF lung fibroblasts was low and unaffected by 5′-aza-2′-deoxycytidine’ treatment. SOCS1 is a target of microRNA-155 and although microRNA-155 levels were increased in IPF tissue, they were reduced in IPF fibroblasts. Therefore, SOCS1 is not regulated by SOCS1 gene methylation or microRNA155 in these cells. In conclusion, we confirmed that IPF fibroblasts had lower levels of SOCS1 mRNA compared with control fibroblasts, but we were unable to determine the mechanism. Furthermore, although SOCS1 may be important in the fibrotic process, we were unable to find a significant role for SOCS1 in regulating fibroblast function.

Pristimerin reduces dextran sulfate sodium-induced colitis in mice by inhibiting microRNA-155

Pristimerin (Pris), which is a natural triterpenoid compound extracted from the Celastraceae plant, has an effect on intestinal inflammation, but its mechanism needs further study. Human genome-wide analysis found that the expression of microRNA-155 in the blood and colon tissue of patients with IBD was increased. Therefore, we studied the effect of Pris on a model of DSS-induced colitis in mice and investigated whether Pris inhibited the expression of microRNA-155. We obtained a mouse model of acute experimental colitis by allowing the mice to drink a 3% by mass DSS solution freely for 7 days. Pris solutions at different concentrations were injected via the abdomen to simulate the therapeutic effect of Pris on colitis. The body weight and faeces were measured and recorded daily. The mice were sacrificed by the cervical dislocation method after the experiment, and the colon length and histological changes, as well as the changes in Nrf2 in the colon tissue, were measured. The activities of the antioxidant enzymes GSH, GSH-Px and SOD were examined. The expression levels of microRNA-155, IL-1β, IL-6, IL-17, and TNF-α in the colon were detected by RT-PCR technology, and the expression of NF-κB p65 in the colon was detected by western blotting. Our study shows that Pris can reduce the DAI score, obviously alleviate weight loss, and decrease the colon pathological tissue damage caused by DSS. Pris can inhibit the increase in microRNA-155 expression induced by DSS-induced colitis. Our study has shown that Pris may reduce DSS-induced colitis in mice by inhibiting the expression of microRNA-155, and further inhibition of the inflammatory response and oxidative stress occurred.

Vitamin D3-Induced Promotor Dissociation of PU.1 and YY1 Results in FcεRI Reduction on Dendritic Cells in Atopic Dermatitis.

Atopic dermatitis (AD) is a severe inflammatory skin disease. Langerhans cells and inflammatory dendritic epidermal cells (IDEC) are located in the epidermis of AD patients and contribute to the inflammatory processes. Both express robustly the high-affinity receptor for IgE, FcεRI, and thereby sense allergens. A beneficial role of vitamin D3 in AD is discussed to be important especially in patients with allergic sensitization. We hypothesized that vitamin D3 impacts FcεRI expression and addressed this in human ex vivo skin, in vitro Langerhans cells, and IDEC models generated from primary human precursor cells. We show in this article that biologically active vitamin D3 [1,25(OH)2-D3] significantly downregulated FcεRI at the protein and mRNA levels of the receptor's α-chain, analyzed by flow cytometry and quantitative RT-PCR. We also describe the expression of a functional vitamin D receptor in IDEC. 1,25(OH)2-D3-mediated FcεRI reduction was direct and resulted in impaired activation of IDEC upon FcεRI engagement as monitored by CD83 expression. FcεRI regulation by 1,25(OH)2-D3 was independent of maturation and expression levels of microRNA-155 and PU.1 (as upstream regulatory axis of FcεRI) and transcription factors Elf-1 and YY1. However, 1,25(OH)2-D3 induced dissociation of PU.1 and YY1 from the FCER1A promotor, evaluated by chromatin immunoprecipitation. We show that vitamin D3 directly reduces FcεRI expression on dendritic cells by inhibiting transcription factor binding to its promotor and subsequently impairs IgE-mediated signaling. Thus, vitamin D3 as an individualized therapeutic supplement for those AD patients with allergic sensitization interferes with IgE-mediated inflammatory processes in AD patients.

Correlation analysis of microribonucleic acid-155 and microribonucleic acid-29 with type2 diabetes mellitus, and the prediction and verification of target genes.

Aims/IntroductionMicroribonucleic acid‐155 (microRNA155) and microRNA29 are reported to inhibit glucose metabolism in some cell and animal models, but no evidence from susceptible populations that examines the relationship between microRNA155 or microRNA29 and type 2 diabetes mellitus currently exists. Furthermore, target genes regulated by microRNA155 and microRNA29 that affect glucose and lipid metabolism remain unknown.Materials and MethodsHuman participants were divided into normal weight (n = 72), obesity (n = 120) and type 2 diabetes (n = 59) groups. The contents of microRNA155 and microRNA29 abundance in serum were measured, and candidate genes potentially related to glucose and lipid metabolism targeted by either microRNA155 or microRNA29 were screened. Overexpression of microRNA155 and microRNA29 in HepG2 cells was used to verify candidate gene expression, and measure the effects on glucose and lipid metabolism.ResultsSerum levels of microRNA155 and microRNA29 show a significant increase in individuals with obesity and type 2 diabetes compared with normal weight individuals. Identified target genes for microRNA155 were MAPK14, MAP3K10, DUSP14 and PRKAR2B. Identified target genes for microRNA29 were PEX11A and FADS1. Overexpression of microRNA155 or microRNA29 in HepG2 cells was found to downregulate the expression of identified target genes, and result in inhibition of triglyceride synthesis and glucose incorporation.ConclusionsMicroRNA155 and microRNA29 were significantly higher in type 2 diabetes patients compared with the control patients, their levels were also positively correlated with fasting plasma glucose levels, and over‐expression of microRNA155 or microRNA29 were found to downregulate glucose and lipid metabolism target genes, and reduce lipid synthesis and glucose incorporation in HepG2 cells.

Docosahexaenoic acid inhibits vascular smooth muscle cell migration and proliferation by decreasing microRNA‑155 expression levels.

Vascular smooth muscle cell (VSMC) hyperplasia is a common cause of carotid restenosis. In the present study, the potential protective effects of docosahexaenoic acid (DHA) in carotid restenosis and the underlying mechanism of its effects were examined. VSMCs were treated with DHA, a polyunsaturated ω-3 fatty acid. Cell migration and proliferation were assessed using wound healing and Cell Counting Kit-8 assays and by measuring Ki-67 protein levels. Additionally, the expression levels of microRNA-155 were determined by reverse transcription-quantitative PCR (RT-qPCR). The involvement of microRNA-155 in the regulation of migration and proliferation was evaluated by transfecting VSMCs with microRNA mimics and inhibitors. Moreover, the reversal of migration and proliferation after transfection of VSMCs with the microRNA mimics and subsequent treatment with DHA was investigated. A target gene of microRNA-155 was identified using RT-qPCR and luciferase assays. The migration and proliferation of VSMCs, as well as the expression of microRNA-155 was inhibited by DHA stimulation. MicroRNA-155 regulated the migration and proliferation of VSMCs. Finally, proliferation and migration of VSMCs were reduced following DHA treatment, which was mediated by an increase in the expression levels of microRNA-155. Suppressor of cytokine signalling 1 (Socs1) was the target gene of microRNA-155. In conclusion, DHA inhibited VSMC migration and proliferation by reducing microRNA-155 expression. This effect may be caused by the microRNA-155 target gene Socs1.

Acute Cardiac Rejection: Antagomir‐155 Attenuates Acute Cardiac Rejection Using Ultrasound Targeted Microbubbles Destruction (Adv. Healthcare Mater. 14/2020)

In article number 2000189 by Li Zhang, Mingxing Xie, and co-workers, cationic microbubbles composed of DOTAP, DSPC, and DSPE-PEG2000 are synthesized to carry antagomir-155 and deliver it to allograft heart in a murine model by ultrasound targeted microbubbles destruction (UTMD). Sonoporation and cavitation make antagomir-155 penetrate vascular endothelium into intracellular region of allograft heart. This therapy downregulates microRNA-155 level in graft heart and attenuates degree of acute cardiac rejection.

Investigation of the miRNA146a and miRNA155 gene expression levels in patients with multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease and the most common neurodegenerative status. MicroRNAs play an important role in macrophage response to inflammatory processes, and alterations in miRNA levels trigger the inactivation of specific T lymphocytes. As a result, these factors can lead to autoimmune diseases such as MS. Therefore, to determine the role of MicroRNA-146a and MicroRNA-155 in MS patients, their expression levels in serum of MS patients were compared with healthy controls.In this study, the expression levels of MicroRNA-146a and MicroRNA-155 in 30 serum samples of MS and healthy patients as a control group. MicroRNA extraction and cDNA synthesis was performed according manufacture protocols. The expression levels of MicroRNAs were evaluated by Real Time-PCR.MicroRNA-146a and MicroRNA-155 levels were increased in patients with MS compared to controls. The results demonstrated that EDSS score are increased with increasing level of MicroRNA-146a and MicroRNA-155. ROC curve analysis showed that the area under curve (AUC) was significant for MicroRNA-146a and MicroRNA-155.Increased expression levels of MicroRNA-146a and MicroRNA-155 may be associated with the pathogenesis of MS disease. If this study is conducted in a larger sample population and the above results can be used to identify patients or control patients who are under medical care.

Plasma Extracellular Vesicle Subtypes as Potential Biomarkers of Immune Activation in HIV-Infected Patients

Chronic immune activation and systemic inflammation during HIV infection despite effective antiretroviral therapy (ART) is associate with non-AIDS co-morbidities in people living with HIV (PLWH). Previous studies have shown that plasma levels of extracellular vesicles (EVs) may be used as immune activation or inflammatory biomarkers of HIV disease progression. Several studies have focused on microRNA and mitochondrial DNA (mtDNA) levels reached concomitantly in immune cells and EVs. We hypothesized that large and small EVs could contain different amounts of microRNA and mtDNA and that could reflect immune activation associated with elevated CD8 T cell count or low CD4/CD8 ratio in PLWH receiving ART. Plasma EVs obtained from PLWH and uninfected control were sized using dynamic light scattering and quantified using flow cytometry. Expression of mature miR-92, miR-155, miR-223 and mtDNA was measured by qRT-PCR. Positive correlation have been observed between CD8+ T cell count and large EV abundance, AChE activity in small EVs and negative correlation with miR-155 levels in small EVs. CD4/CD8 ratio was positively correlated with large EVs abundance and negatively with AChE activity in small EVs and PMN-associated copies of miR-92. MicroRNA-155 level in small EVs were positively correlated with monocyte counts. MiR-155 and mtDNA contents of large EVs were increased more than miR-92 and miR-223 contents in small EVs. A positive correlation was observed between large EVs mtDNA content and CD4 T cell count. These findings suggest that profiling the microRNA and mtDNA contents of EV might provide new functional biomarkers of immune activation and inflammation. Funding Statement: This study was funded through Canadian Institutes of Health Research (CIHR) grants MOP 188726; MOP-267056 (HIV/AIDS initiative) to C.G., MOP-03230 to J.P.R. and to C.T. for the cohort establishment and CIHR Foundation Grant FDN-143218 to M.A. for the studentship awarded to W.W.B., as well as by the Fonds de recherche du Quebec – Sante (FRQ-S) AIDS and infectious diseases network. C.T. is an FRQ-S scholar and holder of the Pfizer/Universite de Montreal chair on HIV translational Research. J-P.R. holds the Louis Lowenstein chair in Hematology & Oncology at McGill University. M-A.J. holds a CIHR Canada Research Chair tier 2 in Immuno-Virology. The infrastructure of the Centre de recherche du CHU de Quebec – Universite Laval is supportes by the FRQ-S. Declaration of Interests: The authors declare that no competing interests exist. Ethics Approval Statement: This study received approval from the ethics review boards of Centre de recherche du CHU de Quebec, Quebec, Canada and the McGill University Health Centre, Montreal, Quebec, Canada. All subjects were anonymous volunteers and provided written informed consent to participate in the study.

Improvement of lung ischemia-reperfusion injury by inhibition of microRNA-155 via reductions in neuroinflammation and oxidative stress of vagal afferent nerve.

Lung ischemia–reperfusion injury (LIRI) is a common clinical concern. As the injury occurs, the pulmonary afferent nerves play a key role in regulating respiratory functions under pathophysiological conditions. The present study was to examine the effects of inhibiting microRNA-155 on the levels of proinflammatory cytokines and products of oxidative stress in the pulmonary vagal afferent nerves and the commissural nucleus of the solitary tract (cNTS) after LIRI. A rat model of LIRI was used. ELISA method was employed to examine proinflammatory cytokines, namely, IL-1β, IL-6 and TNF-α; and key biomarkers of oxidative stress, 8-isoprostaglandin F2α (8-iso PGF2α) and 8-hydroxy-2′-deoxyguanosine (8-OHdG). In results, in the process of LIRI, the levels of microRNA-155 were amplified in the vagal afferent nerves and cNTS, and this was accompanied with increases of IL-1β, IL-6 and TNF-α; and 8-iso PGF2α and 8-OHdG. Application of microRNA-155 inhibitor, but not its scramble, attenuated the elevation of proinflammatory cytokines and amplification of 8-iso PGF2α and 8-OHdG in those nerve tissues. In conclusion, we observed the abnormalities in the pulmonary afferent pathways at the levels of the peripheral nerves and brainstem, which is likely to affect respiratory functions as LIRI occurs. Our data suggest that blocking microRNA-155 signal pathways plays a beneficial role in regulating LIRI via inhibiting responses of neuroinflammation and oxidative stress signal pathways to LIRI.

Expression and Significance of MicroRNA155 in Serum of Patients with Cerebral Small Vessel Disease.

ObjectiveThis study aimed to investigate the changes and significance of microRNA155 levels in serum of patients with cerebral small vessel disease (CSVD). MethodsThirty patients with CSVD who met the inclusion criteria were selected and divided into eight patients with lacunar infarction (LI) group and 22 patients with multiple lacunar infarction (MLI) combined with white matter lesions (WML) group according to the results of head magnetic resonance imaging (MRI). Thirty samples from healthy volunteers without abnormalities after head MRI examination were selected as the control group. The levels of serum microRNA155 in each group were determined by real-time polymerase chain reaction, and the correlation between microRNA155 in the serum of patients with CSVD and the increase of imaging lesions was analyzed by Spearman correlation analysis. ResultsCompared with the control group, the serum microRNA155 level in the LI group, MLI combined with WML group increased, the difference was statistically significant (p<0.05); serum microRNA155 level was positively correlated with the increase of imaging lesions (p<0.05). ConclusionThe change of serum microRNA155 level in patients with CSVD may be one of its self-protection mechanisms, and the intensity of this self-protection mechanism is positively correlated with the number of CSVD lesions.

MicroRNA-155 and FOXP3 jointly inhibit the migration and invasion of colorectal cancer cells by regulating ZEB2 expression.

The study aimed to explore whether microRNA-155 and FOXP3 could regulate invasive and migratory capacities of colorectal cancer (CRC) cells by mediating Zinc finger E-box binding homeobox 2 (ZEB2) expression. Dual-luciferase reporter gene assay was performed to detect the binding condition between microRNA-155, FOXP3, and ZEB2. Protein and mRNA levels of ZEB2 in CRC cells were detected after overexpression of microRNA-155 and FOXP3 by Western blot and quantitative Real Time-Polymerase Chain Reaction (qRT-PCR), respectively. In vitro experiments were conducted using HCT116 and SW620 cell lines. We first detected expression levels of microRNA-155, FOXP3, and ZEB2 in the normal colorectal epithelial cell line (NCM460) and CRC cell lines (HCT116 and SW620) by qRT-PCR. Protein expressions of ZEB2, E-cadherin, and vimentin in WT, LV-GFP, and LV-FOXP3 groups were detected. Wound healing assay and transwell assay were conducted to determine the regulatory effects of microRNA-155 and FOXP3 on invasive and migratory capacities of CRC cells, respectively. Dual-luciferase reporter gene assay found that FOXP3 binds to the promoter and intron regions of ZEB2, and microRNA-155 binds to the 3'UTR region of wild-type ZEB2. Overexpression of FOXP3 downregulated mRNA and protein levels of ZEB2. ZEB2 was highly expressed, whereas microRNA-155 and FOXP3 were lowly expressed in HCT116 and SW620 cells than NCM460 cells. MicroRNA-155 overexpression upregulated E-cadherin and downregulated vimentin in CRC cells. Overexpression of FOXP3 and microRNA-155 inhibited invasive and migratory capacities of CRC cells. MicroRNA-155 and FOXP3 can jointly regulate ZEB2 expression, thereby inhibiting the migration and invasion of colorectal cancer cells.

NF-\u03baB-responsive miR-155 induces functional impairment of vascular smooth muscle cells by downregulating soluble guanylyl cyclase

Vascular smooth muscle cells (VSMCs) play an important role in maintaining vascular function. Inflammation-mediated VSMC dysfunction leads to atherosclerotic intimal hyperplasia and preeclamptic hypertension; however, the underlying mechanisms are not clearly understood. We analyzed the expression levels of microRNA-155 (miR-155) in cultured VSMCs, mouse vessels, and clinical specimens and then assessed its role in VSMC function. Treatment with tumor necrosis factor-α (TNF-α) elevated miR-155 biogenesis in cultured VSMCs and vessel segments, which was prevented by NF-κB inhibition. MiR-155 expression was also increased in high-fat diet-fed ApoE−/− mice and in patients with atherosclerosis and preeclampsia. The miR-155 levels were inversely correlated with soluble guanylyl cyclase β1 (sGCβ1) expression and nitric oxide (NO)-dependent cGMP production through targeting the sGCβ1 transcript. TNF-α-induced miR-155 caused VSMC phenotypic switching, which was confirmed by the downregulation of VSMC-specific marker genes, suppression of cell proliferation and migration, alterations in cell morphology, and NO-induced vasorelaxation. These events were mitigated by miR-155 inhibition. Moreover, TNF-α did not cause VSMC phenotypic modulation and limit NO-induced vasodilation in aortic vessels of miR-155−/− mice. These findings suggest that NF-κB-induced miR-155 impairs the VSMC contractile phenotype and NO-mediated vasorelaxation by downregulating sGCβ1 expression. These data suggest that NF-κB-responsive miR-155 is a novel negative regulator of VSMC functions by impairing the sGC/cGMP pathway, which is essential for maintaining the VSMC contractile phenotype and vasorelaxation, offering a new therapeutic target for the treatment of atherosclerosis and preeclampsia.

Activated CLL B Cells Variably Modulate microRNA-155 Levels in Naïve CD4+ T Cells, and the Direction and Magnitude of microRNA-155 Change Correlates with Th17 Levels and Clinical Course

T-helper 17 (Th17) cells constitute a subset of T cells that characteristically secrete IL-17. In addition to their normal adaptive immune functions, Th17 cells also play roles in supporting dysfunctional immune responses found in autoimmunity and cancer. Several studies suggest that Th17 cells play a protective role in chronic lymphocytic leukemia (CLL). For example, CLL patients exhibit varied levels of circulating Th17 cells, and elevated levels positively correlate with better clinical outcome regardless of IGHV-mutation status. To understand this relationship and elucidate the cellular and molecular mechanisms of Th17 generation in CLL, in particular the role of microRNAs known to affect Th17 development, we investigated cross-talk between naïve CD4+ T cells and CLL B cells. Moreover, since intraclonal leukemic B-cell subpopulations differing in time since cell birth/division can exhibit different functional effects on antigen presentation, we explored the effect of B-cell activation on this T - leukemic B-cell dialogue and how it affects the generation of Th17 cells.To determine potential candidates differentially expressed in CLL, we conducted genome-wide single-cell expression analysis comparing fluorescence activated cell sorting (FACS)-purified mature Th17 cells (CD3+/CD4+/CD45+/CD161+/CCR6+/ CCR4+/CXCR3-) from CLL patients and healthy donors. Selected candidate genes met the criteria of >7-fold increase in expression in CLL, adjusted p-value <1.5 x 10-6, and link to lymphocyte biology. Among selected candidates, microRNA-155 (miR-155), a critical regulator of Th17 differentiation, was found. Follow-up real time, quantitative PCR (RT-qPCR) analyses indicated a significant increase (P < 0.01) in miR-155 expression in CLL Th17 cells as compared to Th17 cells from healthy controls. Since there was no difference in expression between naïve T cells (CD3+/CD4+/CD62L+/CD45RO-) cells, this suggested a CLL-unique mechanism of miR-155 modulation.To determine whether CLL cells directly influence miR-155 levels in naïve CD4+ T cells, co-culture experiments using autologous leukemic or healthy B cells were carried out. FACS-purified peripheral blood naïve CD4+ T cells and B cells from CLL patients and from age-matched healthy controls were co-cultured for 3 days, and expression of T-cell miR-155 was determined by RT-qPCR. In the presence of unstimulated CLL or healthy B cells, miR-155 expression in naïve T cells remained unchanged across all co-cultures. However, upon activation, healthy and leukemic B cells exerted differential effects on miR-155 expression in autologous naïve T cells. In the presence of autologous healthy B cells pre-activated with CpG-ODN2006 and IL-15, miR-155 expression in healthy naïve T cells was significantly increased (P = 0.0313) across all samples. Conversely, CLL naïve T cells co-cultured with autologous, pre-activated leukemic B cells showed heterogeneous modulation of miR-155. Of interest, the magnitude and direction of miR-155 changes in the autologous CLL co-cultures positively correlated not only with circulating Th17 levels (P = 0.019), as determined by flow cytometry, but also with patient time to first treatment (P = 0.0003). Moreover, when samples were divided into 2 groups based on an increase or decrease in miR-155 levels after exposure to activated compared to resting CLL B cells, a significant difference was seen with median survival of 237 months and 67 months, respectively (P = 0.005). Consistent with previous observations from our lab, this correlation was independent of various prognostic markers, including IGHV-mutation status.Our results suggest the existence of a miR-155 modulatory mechanism mediated by CLL B cells that differs based on leukemic B-cell activation state and the degree of change occurring when naïve T cells are exposed to resting vs. activated B cells. Moreover, this variable effect in CLL patients differs from that in normal individuals, and the effect influences number of Th17 cells and patient outcome. Studies are underway to determine the effects that leukemic B cells, unstimulated or CpG-ODN2006 + IL-15 stimulated, have on autologous naïve T-cell maturation into Th17 cells, and the extent that this process depends on the variable miR-155 modulatory capacity of leukemic B cells. DisclosuresChiorazzi:Janssen, Inc: Consultancy; AR Pharma: Equity Ownership.

MicroRNA-155 Amplifies Nitric Oxide/cGMP Signaling and Impairs Vascular Angiotensin II Reactivity in Septic Shock.

Septic shock is a life-threatening clinical situation associated with acute myocardial and vascular dysfunction, whose pathophysiology is still poorly understood. Herein, we investigated microRNA-155-dependent mechanisms of myocardial and vascular dysfunction in septic shock. Prospective, randomized controlled experimental murine study and clinical cohort analysis. University research laboratory and ICU at a tertiary-care center. Septic patients, ICU controls, and healthy controls. Postmortem myocardial samples from septic and nonseptic patients. Ex vivo evaluation of arterial rings from patients undergoing coronary artery bypass grafting. C57Bl/6J and genetic background-matched microRNA-155 knockout mice. Two mouse models of septic shock were used. Genetic deletion and pharmacologic inhibition of microRNA-155 were performed. Ex vivo myographic studies were performed using mouse and human arterial rings. We identified microRNA-155 as a highly up-regulated multifunctional mediator of sepsis-associated cardiovascular dysfunction. In humans, plasma and myocardial microRNA-155 levels correlate with sepsis-related mortality and cardiac injury, respectively, whereas in murine models, microRNA-155 deletion and pharmacologic inhibition attenuate sepsis-associated cardiovascular dysfunction and mortality. MicroRNA-155 up-regulation in septic myocardium was found to be mostly supported by microvascular endothelial cells. This promoted myocardial microvascular permeability and edema, bioenergetic deterioration, contractile dysfunction, proinflammatory, and nitric oxide-cGMP-protein kinase G signaling overactivation. In isolate cardiac microvascular endothelial cells, microRNA-155 up-regulation significantly contributes to LPS-induced proinflammatory cytokine up-regulation, leukocyte adhesion, and nitric oxide overproduction. Furthermore, we identified direct targeting of CD47 by microRNA-155 as a novel mechanism of myocardial and vascular contractile depression in sepsis, promoting microvascular endothelial cell and vascular insensitivity to thrombospondin-1-mediated inhibition of nitric oxide production and nitric oxide-mediated vasorelaxation, respectively. Additionally, microRNA-155 directly targets angiotensin type 1 receptor, decreasing vascular angiotensin II reactivity. Deletion of microRNA-155 restored angiotensin II and thrombospondin-1 vascular reactivity in LPS-exposed arterial rings. Our study demonstrates multiple new microRNA-155-mediated mechanisms of sepsis-associated cardiovascular dysfunction, supporting the translational potential of microRNA-155 inhibition in human septic shock.