Rheumatoid arthritis is a disabling autoimmune disease, characterized by inflammation of synovial tissues and cartilage degradation. Long non-coding RNAs (lncRNAs), are functional RNAs that modulate gene expression through multiple mechanisms, such as epigenetics, alternative splicing, small RNA sponging and transcriptional and translational regulation. Recent studies have shown a dysregulation of lncRNAs in rheumatoid arthritis and others inflammatory diseases. In particular, evidences have revealed increased expression levels of Grow arrest-specific 5 (GAS5), which up-regulates the gene expression of several MMPs and stimulates apoptosis1, and metastasis‐associated lung adenocarcinoma transcript 1 (MALAT1), that increases p38 MAPK and NF-kB activation2. Hyaluronan (HA) is a non-sulfated major glycosaminoglycan (GAG) of the ECM and may exert different action depending on its degree of polymerization. It was reported that high molecular weight HA reduces inflammation in several experimental in vivo and in vitro models, but the exact mechanism seems to be yet unclear3. In this study we aimed to investigate the influence of HA on the gene expression of lncRNA GAS5 and MALAT1 and related microRNAs, miR21 and miR‐125b, in human chondrocytes stimulated with lipopolysaccharide (LPS). Cell viability and apoptosis were assessed using MTT assay and caspase-3 activity. The expression levels of GAS-5, MALAT1, miR21 and miR‐125b were measured using RTqPCR. The protein level of interleukin‐1β (IL‐1β), IL ‐6 and NF-kB was assayed by ELISA kits. LPS treatment decreased cell viability, increased cell apoptosis and promoted NF-kB activation and the release of pro-inflammatory factors. Furthermore, the expression levels of GAS5 and MALAT1 was increased, while miR21 and miR‐125b was decreased in LPS-stimulated chondrocytes. The addition of HA decreased cell apoptosis, NF-κB activation, pro-inflammatory mediators and GAS5 and MALAT1 expression, while partially restored miR21and miR‐125b levels. Together these results show that the HA may exert a protective effect also acting as a negative regulator of GAS5 and MALAT1, that in turn, modulating miR21 and miR‐125b, could contribute to regulate cell survival and inflammatory response.
Hyaluronan modulates the expression levels of lncRNAs MALAT1 and GAS5 in LPS-induced inflammation in mouse chondrocytes
A. D’Ascola;M. Scuruchi;A. Avenoso;G. Bruschetta;S. Campo;G. M. Campo
2018-01-01
Abstract
Rheumatoid arthritis is a disabling autoimmune disease, characterized by inflammation of synovial tissues and cartilage degradation. Long non-coding RNAs (lncRNAs), are functional RNAs that modulate gene expression through multiple mechanisms, such as epigenetics, alternative splicing, small RNA sponging and transcriptional and translational regulation. Recent studies have shown a dysregulation of lncRNAs in rheumatoid arthritis and others inflammatory diseases. In particular, evidences have revealed increased expression levels of Grow arrest-specific 5 (GAS5), which up-regulates the gene expression of several MMPs and stimulates apoptosis1, and metastasis‐associated lung adenocarcinoma transcript 1 (MALAT1), that increases p38 MAPK and NF-kB activation2. Hyaluronan (HA) is a non-sulfated major glycosaminoglycan (GAG) of the ECM and may exert different action depending on its degree of polymerization. It was reported that high molecular weight HA reduces inflammation in several experimental in vivo and in vitro models, but the exact mechanism seems to be yet unclear3. In this study we aimed to investigate the influence of HA on the gene expression of lncRNA GAS5 and MALAT1 and related microRNAs, miR21 and miR‐125b, in human chondrocytes stimulated with lipopolysaccharide (LPS). Cell viability and apoptosis were assessed using MTT assay and caspase-3 activity. The expression levels of GAS-5, MALAT1, miR21 and miR‐125b were measured using RTqPCR. The protein level of interleukin‐1β (IL‐1β), IL ‐6 and NF-kB was assayed by ELISA kits. LPS treatment decreased cell viability, increased cell apoptosis and promoted NF-kB activation and the release of pro-inflammatory factors. Furthermore, the expression levels of GAS5 and MALAT1 was increased, while miR21 and miR‐125b was decreased in LPS-stimulated chondrocytes. The addition of HA decreased cell apoptosis, NF-κB activation, pro-inflammatory mediators and GAS5 and MALAT1 expression, while partially restored miR21and miR‐125b levels. Together these results show that the HA may exert a protective effect also acting as a negative regulator of GAS5 and MALAT1, that in turn, modulating miR21 and miR‐125b, could contribute to regulate cell survival and inflammatory response.Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.