Overexpression of miR-31 in Peripheral Blood Mononuclear Cells (PBMC) from Patients with Ankylosing Spondylitis

Mechanism of miRNA-31 Regulating Wnt/β-catenin Signaling Pathway by Targeting Satb2 in the Osteogenic Differentiation of Human Bone Marrow-Derived Mesenchymal Stem Cells

OBJECTIVE

To explore the expression of miR-31 and Satb2 gene in the serum of postmenopausal women with osteoporosis (OP).

METHODS

97 postmenopausal women with OP and 100 healthy women were selected as research subjects. MSCs were purchased from Shanghai Zhong Qiao Xin Zhou Biotechnology Co., Ltd. Bone marrow-derived mesenchymal stem cells (BMSCs) were isolated, identified and transfected, and then quantified by alkaline phosphatase (ALP) levels. The expression levels of miR-31 and Satb2 gene mRNA were determined by qRT-PCR. The proteins of RUNX2, OCN and BMP and Wnt/β-catenin pathway-related proteins (GSK-3, Frizzled 1, Lrp5, Lrp6 and β-catenin) were tested by Western blotting.

RESULTS

In the OP group, the relative expression of miR-31 was 3.61±0.54, significantly higher than that (1.75±0.27) in the healthy control group (t=9.422, P<0.001). The relative expression of mRNA of Satb2 gene was 0.86±0.12, significantly lower than that (1.35±0.21) in the healthy control group (t=5.897, P<0.001).

CONCLUSIONS

The increase in miR-31 expression can down-regulate the Wnt/β-catenin pathway by targeting the expression of Satb2 gene, thereby inhibiting the osteogenic differentiation of BMSCs. This provides an important reference for further understanding the mechanism of OP and identifying targets for early diagnosis and treatment.

Effect of artificial skin membrane on the expression of miR-155 and miR-506-3p in patients with second-degree burns

OBJECTIVE

To investigate the effect of artificial skin on the expression of miR-155 and miR-506-3p in patients with second-degree burns.

METHODS

The study subjects included 50 patients with second-degree burns treated from July 2019 to July 2021. The control group received routine nursing, while the research group received both routine and artificial skin intervention simultaneously. The changes in wound tissue fibrosis and prognosis were observed. The expression levels of miR-155 and miR-506-3p and their downstream regulatory factors were detected and correlated with the rehabilitation of patients after artificial skin treatment.

RESULTS

After treating second-degree burns with artificial skin membranes, the patient's wound tissue fibrosis and inflammation level improved. At the same time, the expression levels of miR-155 and miR-506-3p in related tests were higher than those in patients with available treatment.

CONCLUSION

The effect of artificial skin membrane on the wound healing of second-degree burn patients may be realized by influencing the expression levels of miR-155 and miR-506-3p and their related signaling pathways.

MicroRNAs as Biomarkers for the Diagnosis of Ankylosing Spondylitis: A Systematic Review and Meta-Analysis

Background: Abnormal expression levels of microRNAs (miRNAs) were observed in ankylosing spondylitis (AS) in recent articles, suggesting that miRNAs may be used as biomarkers for AS diagnoses. In this paper, we conducted a meta-analysis to identify the overall diagnostic accuracy of miRNA biomarkers in AS patients. Methods: An extensive search was undertaken in PubMed, Embase, Cochrane databases, and Wan Fang database up to 30 December 2020 using the following key words: ("microRNAs" or "microRNA" or "miRNA" or "miR" or "RNA, Micro" or "Primary MicroRNA") and ("Spondylitis Ankylosing" or "Spondyloarthritis Ankylopoietica" or "Ankylosing Spondylarthritis" or "Ankylosing Spondylarthritides" or "Spondylarthritides Ankylosing" or "Ankylosing Spondylitis") and ("blood" or "serum" or "plasma"). Statistical evaluation of dysregulated miRNAs using the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and the area under the curve (AUC). Results: Twenty-nine articles reporting on the miRNAs of AS were included. A total of 42 miRNAs were observed to be up-regulated and 45 miRNAs were down-regulated in the AS cases compared with the controls. Besides, 29 studies from nine articles were included in our meta-analysis. The pooled sensitivity, specificity, PLR, NLR, DOR, and AUC were 0. 76 (95% CI, 0.70-0.81), 0.80 (95% CI, 0.74-0.85), 3.75 (95% CI, 2.82-5.01), 0.30 (95% CI, 0.24-0.39), 12.32 (95% CI, 7.65-19.83), 0.85 (95% CI, 0.81-0.88), respectively, suggesting a good diagnostic accuracy of miRNAs for AS. Conclusions: Circulating miRNAs are deregulated in AS patients. miRNAs may be used as a relatively non-invasive biomarkers for the detection of AS.

Can altered colostrum miRNA expression profile after cesarean delivery be a risk factor for autoimmune diseases?

PROBLEM

The cesarean section (CS) rate has increased significantly in North America, Western Europe, and Latin America. However, it has been reported that the incidence of inflammatory and autoimmune diseases such as asthma and type 1 diabetes increased in parallel with CS in these countries. Our aim was to investigate the expression level of miRNAs associated with inflammatory response and autoimmune diseases in colostrum samples and contribute to elucidating the role of CS in the pathogenesis of immune system-related diseases.

METHOD OF STUDY

Colostrum samples were taken from voluntary mothers who had 40 normal and 50 cesarean births. miRNAs were extracted from colostrums and detected to miRNA expression profiling (eighty-four miRNAs) by quantitative real-time PCR with the Fluidigm integrated microfluidic circuit technology.

RESULTS

There was a statistically significant change in the expression levels of 17 miRNAs in the colostrums of mothers who had normal and cesarean delivery (p < .05), and all of miRNAs were upregulated in the colostrums of mothers who have had cesarean delivery.

CONCLUSION

Our best knowledge is that the study we conducted was the first to investigate the effect of delivery method (CS or normal) on the miRNA profile of colostrum. Cesarean delivery is a potential risk factor for inflammatory and immune system-related diseases in children due to dysregulation in miRNA expression.

The Potential Importance of MicroRNAs as Novel Indicators How to Manage Patients with Juvenile Idiopathic Arthritis More Effectively

Small, noncoding sequences of ribonucleic acid called microRNAs (miRNAs, miR) are functioning as posttranscriptional regulators of gene expression. As they draw increasing attention of rheumatologists, there is a growing body of evidence concerning specific molecules that may affect the long-term care of patients with inflammatory arthritides. Findings involving children with juvenile idiopathic arthritis (JIA) are still limited though. The aim of the study was to browse the available data on microRNAs which may be utilized as potential biomarkers helpful in diagnosing and monitoring JIA patients. The review contains a brief summary on the most studied sequences: miR-16, miR-125a-5p, miR-146a, miR-155, and miR-223. It is complemented with other miRNAs possibly relevant for JIA (miR-145, miR-23b, miR-27a, and miR-204) and discussion on challenges for using miRNAs in pediatric rheumatology (particularly, issues regarding specificity of biomarkers and measurements involving synovial fluid).

MicroRNA‑204‑5p inhibits the osteogenic differentiation of ankylosing spondylitis fibroblasts by regulating the Notch2 signaling pathway

Ankylosing spondylitis (AS) is a chronic inflammatory systemic disease and is difficult to detect in the early stages. The present study aimed to investigate the role of microRNA (miR)-204-5p in osteogenic differentiation of AS fibroblasts. Bone morphogenetic protein 2 (BMP-2) was used to induce osteogenic differentiation. Cells were divided into the following groups: AS group, AS + BMP-2 group, AS + BMP-2 + miR-negative control group, AS + BMP-2 + miR-204-5p mimics group and AS + BMP-2 + miR-204-5p mimics + pcDNA-Notch2 group. The expression levels of miR-204-5p, Notch2, runt-related transcription factor 2 (RUNX2) and osteocalcin were detected via reverse transcription-quantitative PCR analysis. The binding site between Notch2 and miR-204-5p was predicted using TargetScan software and verified via the dual-luciferase reporter assay. Alkaline phosphatase (ALP) activity was assessed via the ALP assay, while the mineralized nodules area was determined via the Alizarin Red S staining assay. The results demonstrated that Notch2 is a target gene of miR-204-5p. Furthermore, treatment with BMP-2 significantly decreased miR-204-5p expression, and significantly increased ALP activity, the mineralized nodules area and the expression levels of Notch2, RUNX2 and osteocalcin in ligament fibroblasts (all P<0.05). Conversely, transfection with miR-204-5p mimics significantly increased miR-204-5p expression, and significantly decreased ALP activity, the mineralized nodules area and the expression levels of Notch2, RUNX2 and osteocalcin in ligament fibroblasts (all P<0.05). Notably, transfection with pcDNA-Notch2 significantly reversed the inhibitory effects induced by miR-204-5p mimics on the osteogenic differentiation of ligament fibroblasts (all P<0.05). Furthermore, miR-204-5p inhibited the osteogenic differentiation of ligament fibroblasts in patients with AS by targeting Notch2. Thus, miR-204-5p may negatively regulate Notch2 expression and may be a potential therapeutic target for AS. Collectively, the results of the present study provide a theoretical basis for the effective treatment of patients with AS.

Similar dysregulation of lupus-associated miRNAs in peripheral blood mononuclear cells and splenic lymphocytes in MRL/lpr mice

Objective

MicroRNAs (miRNAs) play an important role in the pathogenesis of various autoimmune diseases including systemic lupus erythematosus (SLE; lupus). We have previously reported a common pattern of miRNA dysregulation in splenic lymphocytes from several mouse models of lupus. In this study, we investigated whether there is a similar miRNAs expression dysregulation in peripheral blood mononuclear cells (PBMCs) and splenocytes in a classical murine lupus model, MRL/lpr.

Method

PBMCs were isolated from blood samples of control MRL and lupus MRL/lpr mice aged 14-15 weeks by gradient centrifugation with Histopaque 1083 density media. miRNA TaqMan assays were performed to analyse the expression of 10 lupus-associated miRNAs including miR-182-96-183 cluster, miR-146a, miR-148a, miR-21, miR-31, miR-127, miR-155, and miR-411 in MRL and MRL/lpr PBMCs.

Result

In this study, we found that 8 out of 10 examined miRNAs (miR-21, miR-31, miR-127, miR-155, miR-96, miR-182, miR-183 and miR-411) were similarly dysregulated in both PBMCs and splenocytes of MRL/lpr mice when compared with MRL control mice. Only two miRNAs (miR-146a and miR-148a) showed different dysregulation pattern in the PBMCs and splenocytes of MRL/lpr mice. By comparing with the published miRNA data in human lupus, we demonstrated similarity in miRNA dysregulation in murine and human lupus PBMCs.

Conclusion

The findings in this study suggest that the miRNA changes observed in PBMCs largely reflect the miRNA dysregulation in cells from the lymphoid organ spleen. Analysis of miRNAs in PBMCs has an advantage over the splenocytes since it allows for monitoring the kinetics of lupus-associated miRNAs expression with peripheral blood cell samples during the development of the disease or after instituting treatment. The similar dysregulation of miRNAs in murine and human lupus PBMCs supports the importance and the feasibility of using murine lupus models to study the pathogenic and therapeutic function of miRNAs in human lupus.