Long noncoding RNA MALAT-1 is a novel inflammatory regulator in human systemic lupus erythematosus

J of Cellular Biochemistry

Zhao

et al. 2018

Osteoarthritis is the most frequent chronic bone-joint disease in middle-aged and older people worldwide. This study investigated the effects of long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) on lipopolysaccharide (LPS)-induced murine chondrogenic ATDC5 cell inflammatory injury. Cell viability and apoptosis were assessed using cell counting kit-8 assay and annexin V-phycoerythrin (PE) staining, respectively. The expression levels of interleukin-1β (IL)-1β, IL-6, IL-8, tumor necrosis factor α (TNF-α), MALAT1, and microRNA-19b (miR)-19b were measured using quantitative reverse-transcription polymerase chain reaction. Enzyme-linked immunosorbent assay was conducted to detect the concentrations of IL-1β, IL-6, IL-8, and TNF-α in culture supernatant of ATDC5 cells. Expressions of key factors involved in cell apoptosis, proinflammatory response, Wnt/β-catenin, and nuclear factor κB (NF-κB) pathways were analyzed using Western blot analysis. We found that LPS treatment remarkably induced ATDC5 cell apoptosis and inflammatory injury. MALAT1 was upregulated in LPS-stimulated ATDC5 cells. Overexpression of MALAT1 significantly reversed the LPS-induced ATDC5 cell inflammatory injury, while suppression of MALAT1 had opposite effects. Further results showed that MALAT1 positively regulated the expression of miR-19b in ATDC5 cells. Knockdown of miR-19b reversed the protective effect of MALAT1 on LPS-induced ATDC5 cells. In addition, MALAT1 reduced LPS-induced Wnt/β-catenin and NF-κB pathways activation in ATDC5 cells by upregulating miR-19. To conclude, our research verified that MALAT1 alleviated LPS-induced ATDC5 cell inflammatory injury by upregulating miR-19b and inactivating Wnt/β-catenin and NF-κB pathways. This finding will be helpful for further understanding the critical roles of MALAT1 and miR-19b in osteoarthritis and may provide possible targets for osteoarthritis diagnosis and treatment.

Section: Introductionmentioning

confidence: 99%

Retracted: Long noncoding RNA MALAT1 alleviates lipopolysaccharide‐induced inflammatory injury by upregulating microRNA‐19b in murine chondrogenic ATDC5 cells

Lin

J of Cellular Biochemistry

Zhao

et al. 2018

“…This study indicated a different expression of lncRNAs in moDCs, which involved in SLE pathogenesis [77]. And, lncRNA MALAT-1, which significantly upregulated in SLE monocytes, is a pivotal regulator in SLE development and provided novel target for therapeutic intervention [78]. Human monocytes lncRNA NEAT1 was highly expressed in lupus patients and positively correlated with disease activity.…”

Section: Lncrna and Sle Pathogenesismentioning

confidence: 80%

Extracellular RNA in systemic lupus erythematosus

Wang

2019

ExRNA

Since the discovery of extracellular RNA (exRNA), it has been shown that exRNAs play a significant role as a transducer in intercellular communication and biomarkers in various diseases. Systemic lupus erythematosus (SLE) is a kind of autoimmune disease that has protean manifestations. The survival and long-term prognosis of patients with SLE has improved in these 5-10 years, while disease pathogenesis is still not clear. Many researchers found the changes in exRNA profile, and exRNAs are likely participating in the process of SLE. In this review, we summarize the current profile and function of exRNA in SLE. Circulating miRNAs, in particular, have been identified as biomarkers for SLE diagnosis. We also explore the function of lncRNA in SLE and the potential correlation with disease progression and activity. These studies show that exRNAs may take parts in the process of SLE and some of them can be used as diagnostic tool for SLE.

Arthritis & Rheumatology

“…In hepatocellular carcinoma cells, MALAT1 knockdown decreased the expression of CXCL8 and IL‐6 . In human endothelial cells, depletion of MALAT1 with small interfering RNA (siRNA) reduced the expression of TNF and IL‐6 , while MALAT1 knockdown in monocytes from patients with systemic lupus erythematosus reduced the expression of IL‐21 . In vivo, inflammation markers, including IL‐6, IL‐1β, TNF, and interferon‐γ, were all supressed in MALAT1‐knockout diabetic mice compared to wild‐type mice .…”

Section: Discussionmentioning

confidence: 99%

Regulation of the Inflammatory Synovial Fibroblast Phenotype by Metastasis‐Associated Lung Adenocarcinoma Transcript 1 Long Noncoding RNA in Obese Patients With Osteoarthritis

Nanus

Wijesinghe

Pearson

et al. 2020

Objective To identify long noncoding RNAs (lncRNAs) associated with the inflammatory phenotype of synovial fibroblasts from obese patients with osteoarthritis (OA), and to explore the expression and function of these lncRNAs. Methods Synovium was collected from normal‐weight patients with hip fracture (non‐OA; n = 6) and from normal‐weight (n = 8) and obese (n = 8) patients with hip OA. Expression of RNA was determined by RNA‐sequencing and quantitative reverse transcription–polymerase chain reaction. Knockdown of lncRNA was performed using LNA‐based GapmeRs. Synovial fibroblast cytokine production was measured by enzyme‐linked immunosorbent assay. Results Synovial fibroblasts from obese patients with OA secreted greater levels of interleukin‐6 (IL‐6) (mean ± SEM 162 ± 21 pg/ml; P < 0.001) and CXCL8 (262 ± 67 pg/ml; P < 0.05) compared to fibroblasts from normal‐weight patients with OA (IL‐6, 51 ± 4 pg/ml; CXCL8, 78 ± 11 pg/ml) or non‐OA patients (IL‐6, 35 ± 3 pg/ml; CXCL8, 56 ± 6 pg/ml) (n = 6 patients per group). RNA‐sequencing revealed that fibroblasts from obese OA patients exhibited an inflammatory transcriptome, with increased expression of proinflammatory messenger RNAs (mRNAs) as compared to that in fibroblasts from normal‐weight OA or non‐OA patients (>2‐fold change, P < 0.05; n = 4 patients per group). A total of 19 lncRNAs were differentially expressed between normal‐weight OA and non‐OA patient fibroblasts, and a further 19 lncRNAs were differentially expressed in fibroblasts from obese OA patients compared to normal‐weight OA patients (>2‐fold change, P < 0.05 for each), which included the lncRNA for metastasis‐associated lung adenocarcinoma transcript 1 (MALAT1). MALAT1 was rapidly induced upon stimulation of OA synovial fibroblasts with proinflammatory cytokines, and was up‐regulated in the synovium from obese OA patients as compared to normal‐weight OA patients (1.6‐fold change, P < 0.001) or non‐OA patients (6‐fold change, P < 0.001). MALAT1 knockdown in OA synovial fibroblasts (n = 4 patients) decreased the levels of mRNA expression and protein secretion of CXCL8 (>1.5‐fold change, P < 0.01), whereas it increased expression of mRNAs for TRIM6 (>2‐fold change, P < 0.01), IL7R (<2‐fold change, P < 0.01), HIST1H1C (>1.5‐fold change, P < 0.001), and MAML3 (>1.5‐fold change, P < 0.001). In addition, MALAT1 knockdown inhibited the proliferation of synovial fibroblasts from obese patients with OA. Conclusion Synovial fibroblasts from obese patients with hip OA exhibit an inflammatory phenotype. MALAT1 lncRNA may mediate joint inflammation in obese OA patients.