Anti-proliferative effect of recombinant human endostatin on synovial fibroblasts in rats with adjuvant arthritis.
Rheumatoid arthritis (RA) is characterized by pronounced synovial hyperplasia resulting in pannus formation, cartilage erosion and ultimately joint destruction. Activated RA synovial fibroblasts (SFs) mediate the invasion and destruction of cartilage and bone. We previously demonstrated that recombinant human endostatin (rhEndostatin) is sufficient to induce SF apoptosis in adjuvant arthritis (AA) rats. However, the effect of this protein on SF proliferation is unknown. This study was designed to assess the inhibitory effect and mechanisms of rhEndostatin on the proliferation of cultured AA SFs. MTT assay and flow cytometric detection were performed to investigate SF proliferation and cell cycle progression, respectively. Also, the expression levels of p53, p21, cyclin D1, CDK4 and PCNA in AA SFs were detected by real-time PCR and western blotting assays. Our data revealed that AA SF proliferation was significantly inhibited by rhEndostatin in a concentration-dependent manner. In addition, rhEndostatin (50μg/ml) caused the G0/G1 cell cycle arrest of AA SFs. There were significant decreases in the expression levels of p53, p21, cyclin D1 and PCNA in AA SFs treated with rhEndostatin, and a significant increase in CDK4 expression. Collectively, our data suggest that rhEndostatin inhibits AA SF proliferation, which is preceded by cell cycle arrest at the G0/G1 phase. This is partly due to the inhibitory effect of rhEndostatin on cyclin D1 and PCNA by a p53-p21-CDK4-independent mechanism. Taken together, these findings highlight the potential use of rhEndostatin for RA treatment.
School of Pharmacy, Anhui Medical University, 81 Meishan Road, Hefei 230032, China; Department of Anatomy, Anhui Medical University, 81 Meishan Road, Hefei 230032, China. Electronic address: hxy8676@126.com.
Xue-Ying
XY
Huang
Department of Anatomy, Anhui Medical University, 81 Meishan Road, Hefei 230032, China. Electronic address: zhxm_1919@126.com.
Xiao-Ming
XM
Zhang
School of Pharmacy, Anhui Medical University, 81 Meishan Road, Hefei 230032, China. Electronic address: cfhchina@sohu.com.
Fei-Hu
FH
Chen
Department of Pharmacology, Anhui Medical University, 81 Meishan Road, Hefei 230032, China. Electronic address: lanlzhou@aliyun.com.
Lan-Lan
LL
Zhou
Department of Anatomy, Anhui Medical University, 81 Meishan Road, Hefei 230032, China. Electronic address: knowou@163.com.
Xue-Fei
XF
Deng
Department of Cardiothoracic Surgery, PLA 105 Hospital, 424 Changjiang Road, Hefei 230032, China. Electronic address: yongjingliu@163.com.
Yong-Jing
YJ
Liu
Department of Plastic Surgery, The First Affiliated Hospital, Anhui Medical University, 218 Jixi Road, Hefei 230022, China. Electronic address: lixiaojing5@163.com.
Xiao-Jing
XJ
Li
D000818:Animals; D018501:Antirheumatic Agents / Q000494:pharmacology*; D001169:Arthritis, Experimental / Q000378:metabolism*; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D019938:Cyclin D1 / Q000235:genetics / Q000378:metabolism; D051358:Cyclin-Dependent Kinase 4 / Q000235:genetics / Q000378:metabolism; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism; D043169:Endostatins / Q000494:pharmacology*; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D008297:Male; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000494:pharmacology; D013583:Synovial Membrane / Q000166:cytology*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
D018501:Antirheumatic Agents; C530106:Ccnd1 protein, rat; D050759:Cyclin-Dependent Kinase Inhibitor p21; D043169:Endostatins; D018809:Proliferating Cell Nuclear Antigen; D012333:RNA, Messenger; D011994:Recombinant Proteins; D016159:Tumor Suppressor Protein p53; D019938:Cyclin D1; C495903:Cdk4 protein, rat; D051358:Cyclin-Dependent Kinase 4
Proliferation; Recombinant human endostatin; Rheumatoid arthritis; Synovial fibroblast