Abstract:Objective To investigate the basic mechanism of LncRNA GAS5 in osteoarthritis.Methods 14 normal knee cartilage tissues were collected from patients who received internal fixation for tibial plateau fracture in Zhongshan Hospital Wusong Branch,Fudan University from July 2018 to July 2020,including 8 males and 6 females.The age ranged from 19 to 40 years,with an average of (31±5) years.35 OA knee cartilage tissues were collected from patients diagnosed with OA and indicated for knee replacement surgery in Zhongshan Hospital Wusong Branch of Fudan University from July 2018 to July 2020,including 17 males and 18 females.The average age was (70±4) years.The expression of TIMP-3 mRNA was detected by real time quantitative polymerase chain reaction (RT-qPCR).OA cell model was established by treatment with interleukin-1β (10 ng/mL).GSE16464 OA gene chips were analyzed.The expression of TIMP-3 was detected by RT-qPCR and Western blot.CpG islands enriched in TIMP-3 promoter region were detected by chip quantitative polymerase chain reaction,qPCR (qPCR).The target relationship between GAS5 and TIMP-3 was predicted by bioinformatics method,and verified by double luciferase reporter gene detection.Results TIMP-3 mRNA expression in OA patients was significantly lower than that in normal cartilage tissues.The positive rates of TIMP-3 promoter methylation in OA patients and normal cartilage tissue controls were 72.1% and 35.7%,respectively.The expression of LncRNA GAS5 in OA was significantly higher than that in normal cartilage tissues (P<0.05).Blast sequence alignment has binding site between GAS5 sequence and TIMP-3 promoter sequence.Silencing LncRNA GAS5 promoted TIMP-3 expression and inhibited collagen degradation in OA chondrocytes.Double luciferase reporter gene assay confirmed that GAS5 and TIMP-3 have a targeted regulatory relationship.Conclusion TIMP-3 expression is low in OA cartilage,while LncRNA GAS5 expression was up-regulated; LncRNA GAS5 can enrich DNA methyltransferase,inhibit TIMP-3 expression and promote collagen degradation of chondrocytes.
[1]Allen KD,Golightly YM.State of the evidence[J].Curr Opin Rheumatol,2015,27(3):276-283.
[2]Bierma-Zeinstra S,van Middelkoop M,Runhaar J,et al.Nonpharmacological and nonsurgical approaches in OA[J].Best Pract Res Clin Rheumatol,2020,34(2):101564.
[3]Lin X,Li L,Liu X,et al.Genomewide analysis of aberrant methylation of enhancer DNA in human osteoarthritis[J].BMC Med Genomics,2020,13(1):1.
[4]Pearson MJ,Philp AM,Heward JA,et al.Long intergenic noncoding RNAs mediate the human chondrocyte inflammatory response and are differentially expressed in osteoarthritis cartilage[J].Arthritis Rheumatol,2016,68(4):845-856.
[5]Song J,Ahn C,Chun CH,et al.A long non-coding RNA,GAS5,plays a critical role in the regulation of miR-21 during osteoarthritis[J].J Orthop Res,2014,32(12):1628-1635.
[6]Xing D,Liang JQ,Li Y,et al.Identification of long noncoding RNA associated with osteoarthritis in humans[J].Orthop Surg,2014,6(4):288-293.
[7]Yamamoto K,Okano H,Miyagawa W,et al.MMP-13 is constitutively produced in human chondrocytes and co-endocytosed with ADAMTS-5 and TIMP-3 by the endocytic receptor LRP1[J].Matrix Biol,2016( 56):57-73.
[8]Zhu Y,Gu J,Zhu T,et al.Crosstalk between Smad2/3 and specific isoforms of ERK in TGF-beta1-induced TIMP-3 expression in rat chondrocytes[J].J Cell Mol Med,2017,21(9):1781-1790.
[9]Roach HI,Yamada N,Cheung KS,et al.Association between the abnormal expression of matrix-degrading enzymes by human osteoarthritic chondrocytes and demethylation of specific CpG sites in the promoter regions[J].Arthritis Rheum,2005,52(10):3110-3124.
[10]Mahmoodi M,Sahebjam S,Smookler D,et al.Lack of tissue inhibitor of metalloproteinases-3 results in an enhanced inflammatory response in antigen-induced arthritis[J].Am J Pathol,2005,166(6):1733-1740.
[11]Xia B,Di C,Zhang J,et al.Osteoarthritis pathogenesis:a review of molecular mechanisms[J].Calcif Tissue Int,2014,95(6):495-505.
[12]Bai X,Guo A,Li Y.Protective effects of calcitonin on IL-1stimulated chondrocytes by regulating MMPs/TIMP-1 ratio via suppression of p50-NF-kappaB pathway[J].Biosci Biotechnol Biochem,2019,83(4):598-604.
[13]Rahmati M,Nalesso G,Mobasheri A,et al.Aging and osteoarthritis:Central role of the extracellular matrix[J].Ageing Res Rev,2017(40):20-30.
[14]Burton DW,Foster M,Johnson KA,et al.Chondrocyte calcium-sensing receptor expression is up-regulated in early guinea pig knee osteoarthritis and modulates PTHrP,MMP-13,and TIMP-3 expression[J].Osteoarthritis Cartilage,2005,13(5):395-404.
[15]Rinn JL,Chang HY.Genome regulation by long noncoding RNAs[J].Annu Rev Biochem,2012( 81):145-166.
[16]Huang JL,Zheng L,Hu YW,et al.Characteristics of long non-coding RNA and its relation to hepatocellular carcinoma[J].Carcinogenesis,2014,35(3):507-514.