ABSTRACT
BACKGROUND: Osteoarthritis (OA) is a common joint disease. Currently, many studies have revealed that circular RNAs (circRNAs) are strongly related to the occurrence and development of diseases. Hence, we aimed to further elucidate the role and molecular mechanism of circRNA SEC24 homolog A, COPII coat complex component (circSEC24A) in OA. METHODS: Chondrocytes were treated with interleukin-1ß (IL-1ß) to establish OA cell model in vitro. The expression levels of circSEC24A, microRNA-142-5p (miR-142-5p), and sex-determining region Y-box protein 5 (SOX5) were determined by quantitative real-time polymerase chain reaction. MTT and colony formation assays were used to determine cell proliferation. Cell apoptosis was detected by flow cytometry analysis. The protein levels of inflammatory factors and SOX5 were determined by western blot assay. The relationship between miR-142-5p and circSEC24A or SOX5 was confirmed using dual-luciferase reporter assay and RNA immunoprecipitation assay. RESULTS: CircSEC24A and SOX5 expression were enhanced, while miR-142-5p level was reduced in OA cartilage tissues and chondrocytes. Overexpression of circSEC24A promoted IL-1ß-induced injury through decreasing cell proliferation and increasing apoptosis and inflammation in chondrocytes. MiR-142-5p was a direct target of circSEC24A, and its upregulation ameliorated IL-1ß-induced injury and abated the effect of oe-circSEC24A in IL-1ß-induced chondrocytes. Additionally, SOX5 was a downstream target of miR-142-5p, and its overexpression had a similar role with oe-circSEC24A and reversed the impact of miR-142-5p in IL-1ß-induced chondrocytes. CircSEC24A acted as a molecular sponge of miR-142-5p to regulate SOX5 expression in chondrocytes. CONCLUSION: CircSEC24A aggravated IL-1ß-induced injury via modulating miR-142-5p/SOX5 axis, providing possible targets for the clinical diagnosis and treatment of OA.
Subject(s)
MicroRNAs , Osteoarthritis , Apoptosis , Chondrocytes , Humans , Inflammation/metabolism , Interleukin-1beta/metabolism , Interleukin-1beta/pharmacology , MicroRNAs/metabolism , Osteoarthritis/genetics , Osteoarthritis/metabolism , RNA, Circular/genetics , SOXD Transcription Factors/genetics , SOXD Transcription Factors/metabolism , SOXD Transcription Factors/pharmacologyABSTRACT
Long non-coding RNAs (lncRNAs) have been proved to play critical roles in diabetic nephropathy (DN). This study aimed to investigate the functions and underlying mechanism of potassium voltage-gated channel subfamily Q member 1 overlapping transcript 1 (KCNQ1OT1) in DN. Blood samples were obtained from 33 DN patients and 30 healthy volunteers. Kidney biopsies tissues of DN patients (n = 10) and patients with normal kidney morphology (n = 10) were collected. We found that KCNQ1OT1 was markedly overexpressed in the blood and kidney biopsies tissues of DN patients, as well as in high glucose (HG)-cultured human glomerular mesangial (HGMC) cells. Knockdown of KCNQ1OT1 suppressed proliferation, extracellular matrix (ECM) accumulation, inflammation, and oxidative stress in HG-treated HGMC cells in vitro. KCNQ1OT1 functioned as a sponge for microRNA-147a (miR-147a), and SRY-Box Transcription Factor 6 (SOX6) was directly targeted by miR-147a. Downregulation of miR-147a or upregulation of SOX6 partly overturned the prohibitive effects of KCNQ1OT1 knockdown or miR-147a overexpression on proliferation, ECM accumulation, inflammation, and oxidative stress in HG-treated HGMC cells. Altogether, KCNQ1OT1 mediated the proliferation, ECM accumulation, inflammation, and oxidative stress in HG-treated HGMC cells via miR-147a/SOX6 axis, which might be a novel target for DN therapy.
Subject(s)
Diabetes Mellitus , Diabetic Nephropathies , MicroRNAs , RNA, Long Noncoding , Cell Proliferation , Diabetes Mellitus/metabolism , Diabetic Nephropathies/genetics , Diabetic Nephropathies/metabolism , Extracellular Matrix/genetics , Extracellular Matrix/metabolism , Extracellular Matrix/pathology , Glucose/metabolism , Glucose/pharmacology , Humans , Inflammation/genetics , Inflammation/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Oxidative Stress , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , SOXD Transcription Factors/metabolism , SOXD Transcription Factors/pharmacologyABSTRACT
Target gene transfection for desired cell differentiation has recently become a major issue in stem cell therapy. For the safe and stable delivery of genes into human mesenchymal stem cells (hMSCs), we employed a non-viral gene carrier system such as polycataionic polymer, poly(ethyleneimine) (PEI), polyplexed with a combination of SOX5, 6, and 9 fused to green fluorescence protein (GFP), yellow fluorescence protein (YFP), or red fluorescence protein (RFP) coated onto PLGA nanoparticles. The transfection efficiency of PEI-modified PLGA nanoparticle gene carriers was then evaluated to examine the potential for chondrogenic differentiation by carrying the exogenous SOX trio (SOX5, 6, and 9) in hMSCs. Additionally, use of PEI-modified PLGA nanoparticle gene carriers was evaluated to investigate the potential for transfection efficiency to increase the potential ability of chondrogenesis when the trio genes (SOX5, 6, and 9) polyplexed with PEI were delivered into hMSCs. SOX trio complexed with PEI-modified PLGA nanoparticles led to a dramatic increase in the chondrogenesis of hMSCs in in vitro culture systems. For the PEI/GFP and PEI/SOX5, 6, and 9 genes complexed with PLGA nanoparticles, the expressions of GFP as reporter genes and SOX9 genes with PLGA nanoparticles showed 80% and 83% of gene transfection ratios into hMSCs two days after transfection, respectively.
