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Expression of pro-fibrotic and anti-fibrotic molecules in dimethylnitrosamine-induced hepatic fibrosis. Pathol Res Pract 2016; 213:58-65. [PMID: 27894619 DOI: 10.1016/j.prp.2016.11.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 09/27/2016] [Accepted: 11/08/2016] [Indexed: 02/06/2023]
Abstract
BACKGROUND Hepatic fibrosis is characterized by a progressive accumulation of fibrillar extracellular matrix (ECM) proteins, produced by activated myofibroblasts which are modulated by both profibrotic and antifibrotic factors. OBJECTIVE To evaluate in vivo the expression of pro-fibrotic molecules like avβ6 integrin, transforming growth factor-β (TGF-β), Smad3, connective tissue growth factor (CTGF) and mammalian target of Rapamycin (mTOR), as well as anti-fibrotic peroxisome proliferator-activated receptor-γ (PPARγ) in an experimental model of chronic hepatitis-associated fibrosis induced by intraperitoneal administration of dimethylnitrosamine (DMN) in mice. METHODS Chronic hepatitis was induced in 12 Smad3 wild-type (WT) and 12 knock-out (KO) mice by intraperitoneal DMN administration. Histological, morphometric and immunohistochemical analyses using α-smooth muscle actin (α-SMA), collagen types I-III, TGF-β1, Smad3, avβ6 integrin, CTGF, mTOR and PPARγ antibodies were performed. RESULTS The liver of DMN-treated Smad3 WT mice showed a higher degree of hepatic accumulation of connective tissue compared to KO mice. The expression of α-SMA, collagen I-III and CTGF was increased in Smad3 WT compared to KO mice treated with DMN, associated with a concomitant up-regulation of avβ6, TGFβ, Smad3, and mTOR and a reduction in PPARγ expression. CONCLUSIONS These results suggest a possible interaction between pro-fibrotic and anti-fibrotic molecules in the development of hepatic fibrosis.
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Shan L, Ding Y, Fu Y, Zhou L, Dong X, Chen S, Wu H, Nai W, Zheng H, Xu W, Bai X, Jia C, Dai M. mTOR Overactivation in Mesenchymal cells Aggravates CCl 4- Induced liver Fibrosis. Sci Rep 2016; 6:36037. [PMID: 27819329 PMCID: PMC5098141 DOI: 10.1038/srep36037] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 10/10/2016] [Indexed: 01/22/2023] Open
Abstract
Hepatic stellate cells are of mesenchymal cell type located in the space of Disse. Upon liver injury, HSCs transactivate into myofibroblasts with increase in expression of fibrillar collagen, especially collagen I and III, leading to liver fibrosis. Previous studies have shown mTOR signaling is activated during liver fibrosis. However, there is no direct evidence in vivo. The aim of this study is to examine the effects of conditional deletion of TSC1 in mesenchymal on pathogenesis of liver fibrosis. Crossing mice bearing the floxed TSC1 gene with mice harboring Col1α2-Cre-ER(T) successfully generated progeny with a conditional knockout of TSC1 (TSC1 CKO) in collagen I expressing mesenchymal cells. TSC1 CKO and WT mice were subjected to CCl4, oil or CCl4+ rapamycin treatment for 8 weeks. TSC1 CKO mice developed pronounced liver fibrosis relative to WT mice, as examined by ALT, hydroxyproline, histopathology, and profibrogenic gene. Absence of TSC1 in mesenchymal cells induced proliferation and prevented apoptosis in activated HSCs. However, there were no significant differences in oil-treated TSC1 CKO and WT mice. Rapamycin, restored these phenotypic changes by preventing myofibroblasts proliferation and enhancing their apoptosis. These findings revealed mTOR overactivation in mesenchymal cells aggravates CCl4− induced liver fibrosis and the rapamycin prevent its occurance.
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Affiliation(s)
- Lanlan Shan
- Department of Health Management, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Yan Ding
- Department of Health Management, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - You Fu
- Department of Health Management, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Ling Zhou
- Department of Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Xiaoying Dong
- Department of Health Management, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Shunzhi Chen
- Department of Health Management, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Hongyuan Wu
- Department of Health Management, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Wenqing Nai
- Department of Health Management, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Hang Zheng
- Department of Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Wanfu Xu
- Department of Gastroenterology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Xiaochun Bai
- Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Chunhong Jia
- Department of Cell Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China
| | - Meng Dai
- Department of Health Management, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China
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53
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Rockel JS, Kapoor M. Autophagy: controlling cell fate in rheumatic diseases. Nat Rev Rheumatol 2016; 12:517-31. [DOI: 10.1038/nrrheum.2016.92] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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54
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Xiang S, Li M, Xie X, Xie Z, Zhou Q, Tian Y, Lin W, Zhang X, Jiang H, Shou Z, Chen J. Rapamycin inhibits epithelial-to-mesenchymal transition of peritoneal mesothelium cells through regulation of Rho GTPases. FEBS J 2016; 283:2309-25. [PMID: 27093550 DOI: 10.1111/febs.13740] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 04/01/2016] [Accepted: 04/18/2016] [Indexed: 12/26/2022]
Abstract
Epithelial-mesenchymal transition (EMT) of peritoneal mesothelial cells (PMCs) is a key process of peritoneal fibrosis. Rapamycin has been previously shown to inhibit EMT of PMCs and prevent peritoneal fibrosis. In this study, we investigated the undefined molecular mechanisms by which rapamycin inhibits EMT of PMCs. To define the protective effect of rapamycin, we initially used a rat PD model which was daily infused with 20 mL of 4.25% high glucose (HG) dialysis solution for 6 weeks to induce fibrosis. The HG rats showed decreased ultrafiltration volume and obvious fibroproliferative response, with markedly increased peritoneal thickness and higher expression of α-smooth muscle actin (α-SMA) and transforming growth factor-β1. Rapamycin significantly ameliorated those pathological changes. Next, we treated rat PMCs with HG to induce EMT and/or rapamycin for indicated time. Rapamycin significantly inhibited HG-induced EMT, which manifests as increased expression of α-SMA, fibronectin, and collagen I, decreased expression of E-cadherin, and increased mobility. HG increased the phosphorylation of PI3K, Akt, and mTOR. Importantly, rapamycin inhibits the RhoA, Rac1, and Cdc42 activated by HG. Moreover, rapamycin repaired the pattern of F-actin distribution induced by HG, reducing the formation of stress fiber, focal adhesion, lamellipodia, and filopodia. Thus, rapamycin shows an obvious protective effect on HG-induced EMT, by inhibiting the activation of Rho GTPases (RhoA, Rac1, and Cdc42).
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Affiliation(s)
- Shilong Xiang
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Meng Li
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xishao Xie
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Zhoutao Xie
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Qin Zhou
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yuanshi Tian
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Weiqiang Lin
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Institute of Translational Medicine, Zhejiang University, Hangzhou, China
| | - Xiaohui Zhang
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Hong Jiang
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Zhangfei Shou
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Nephrology department, Zhejiang University International Hospital, Hangzhou, China
| | - Jianghua Chen
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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55
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Sun Y, Zhao S, Li X, Yan L, Wang J, Wang D, Chen H, Dai J, He J. Local application of rapamycin reduces epidural fibrosis after laminectomy via inhibiting fibroblast proliferation and prompting apoptosis. J Orthop Surg Res 2016; 11:58. [PMID: 27154399 PMCID: PMC4859967 DOI: 10.1186/s13018-016-0391-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 04/17/2016] [Indexed: 12/20/2022] Open
Abstract
Background Epidural fibrosis is a common complication after laminectomy. It is associated with intractable lower back pain and additional complications. To date, no study has evaluated whether the local application of rapamycin (RAPA) can inhibit fibroblast proliferation and reduce epidural scar adhesion after laminectomy. The results of the present study showed that the local application of RAPA reduces epidural fibrosis after laminectomy in rats. Methods In this study, 32 male Sprague-Dawley rats were randomly divided into four groups (0.2 mg/ml RAPA-treated group, 0.1 mg/ml RAPA-treated group, 0.05 mg/ml RAPA-treated group and physiological saline group). Laminectomy was performed at the level of lumbar segment 1 to 2, and different concentrations of RAPA or saline were applied to the laminectomy sites for 10 min. Four weeks after laminectomy, the rats were sacrificed, and the degrees of epidural adhesion in each group were evaluated. Macroscopic assessment, analysis of hydroxyproline content, and histological analysis were used to determine the therapeutic effect of the local application of RAPA on the inhibition of fibroblast proliferation and the reduction of epidural fibrosis after laminectomy. Next, we cultured fibroblasts from epidural scar tissues of rats that had undergone laminectomy. Fibroblasts were exposed to the indicated concentrations of RAPA, and western blotting and TUNEL assays were used to assess the effects of RAPA on inhibiting fibroblasts proliferation and promoting fibroblast apoptosis. Results The results of macroscopic assessments, analysis of hydroxyproline content, and histological analyses indicated that RAPA significantly inhibited fibroblast proliferation and reduced epidural fibrosis in the treated groups in the rat model. The western blotting results indicated that the expression levels of the pro-apoptotic proteins cleaved-PARP and Bax were up-regulated, whereas those of Bcl-2 were reduced. TUNEL assay indicated that the apoptosis rates of fibroblasts were significantly increased after exposure to the indicated concentrations of RAPA. Conclusions The local application of RAPA reduced epidural fibrosis after laminectomy by inhibiting the proliferation of fibroblasts, stimulating their apoptosis, and decreasing collagen synthesis. This protocol may be used in new clinical treatment strategies to reduce epidural fibrosis after laminectomy.
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Affiliation(s)
- Yu Sun
- Department of Orthopedics, Clinical medical college of Yangzhou University, Nantong West Road 98, Yangzhou, Jiangsu, 225001, China.,Orthopedics Institute, Subei People's Hospital of Jiangsu Province, Yangzhou, Jiangsu, 225001, China
| | - Shuai Zhao
- Department of Orthopedics, Clinical medical college of Yangzhou University, Nantong West Road 98, Yangzhou, Jiangsu, 225001, China.,Department of Orthopedics, Xiangya Second Hospital, Central South University, Changsha, Hunan, 410012, China.,Orthopedics Institute, Subei People's Hospital of Jiangsu Province, Yangzhou, Jiangsu, 225001, China
| | - Xiaolei Li
- Department of Orthopedics, Clinical medical college of Yangzhou University, Nantong West Road 98, Yangzhou, Jiangsu, 225001, China.,Department of Orthopedics, Xiangya Second Hospital, Central South University, Changsha, Hunan, 410012, China.,Orthopedics Institute, Subei People's Hospital of Jiangsu Province, Yangzhou, Jiangsu, 225001, China
| | - Lianqi Yan
- Department of Orthopedics, Clinical medical college of Yangzhou University, Nantong West Road 98, Yangzhou, Jiangsu, 225001, China. .,Department of Orthopedics, Xiangya Second Hospital, Central South University, Changsha, Hunan, 410012, China. .,Orthopedics Institute, Subei People's Hospital of Jiangsu Province, Yangzhou, Jiangsu, 225001, China.
| | - Jingcheng Wang
- Department of Orthopedics, Clinical medical college of Yangzhou University, Nantong West Road 98, Yangzhou, Jiangsu, 225001, China. .,Department of Orthopedics, Xiangya Second Hospital, Central South University, Changsha, Hunan, 410012, China. .,Orthopedics Institute, Subei People's Hospital of Jiangsu Province, Yangzhou, Jiangsu, 225001, China.
| | - Daxin Wang
- Department of Orthopedics, Clinical medical college of Yangzhou University, Nantong West Road 98, Yangzhou, Jiangsu, 225001, China.,Orthopedics Institute, Subei People's Hospital of Jiangsu Province, Yangzhou, Jiangsu, 225001, China
| | - Hui Chen
- Department of Orthopedics, Clinical medical college of Yangzhou University, Nantong West Road 98, Yangzhou, Jiangsu, 225001, China.,Orthopedics Institute, Subei People's Hospital of Jiangsu Province, Yangzhou, Jiangsu, 225001, China
| | - Jihang Dai
- Department of Orthopedics, Clinical medical college of Yangzhou University, Nantong West Road 98, Yangzhou, Jiangsu, 225001, China.,Orthopedics Institute, Subei People's Hospital of Jiangsu Province, Yangzhou, Jiangsu, 225001, China
| | - Jun He
- Department of Orthopedics, Clinical medical college of Yangzhou University, Nantong West Road 98, Yangzhou, Jiangsu, 225001, China.,Orthopedics Institute, Subei People's Hospital of Jiangsu Province, Yangzhou, Jiangsu, 225001, China
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Pabon MA, Ma KC, Choi AMK. Autophagy and Obesity-Related Lung Disease. Am J Respir Cell Mol Biol 2016; 54:636-46. [PMID: 26900794 PMCID: PMC5455357 DOI: 10.1165/rcmb.2016-0045ps] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Accepted: 02/22/2016] [Indexed: 12/11/2022] Open
Abstract
Obesity-related disease is a significant source of premature death and economic burden globally. It is also a common comorbidity in patients suffering from lung disease, affecting both severity and treatment success. However, this complex association between obesity and the lung is poorly understood. Autophagy is a self-recycling homeostatic process that has been linked to beneficial or deleterious effects, depending on the specific lung disease. Obesity affects autophagy in a tissue-specific manner, activating autophagy in adipocytes and impairing autophagy in hepatocytes, immune cells, and pancreatic β-cells, among others. Obesity is also characterized by chronic low-grade inflammation that can be modulated by the pro- and antiinflammatory effects of the autophagic machinery. Scant evidence exists regarding the impact of autophagy in obesity-related lung diseases, but there are communal pathways that could be related to disease pathogenesis. Important signaling molecules in obesity, including IL-17, leptin, adiponectin, NLRP3 inflammasome, and TLR-4, have been implicated in the pathogenesis of lung disease. These mediators are known to be modulated by autophagy activity. In this perspective, we highlight the recent advances in the understanding of autophagy in obesity-related conditions, as well as the potential mechanisms that can link autophagy and obesity in the pathogenesis of lung disease.
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Affiliation(s)
- Maria A Pabon
- Division of Pulmonary and Critical Care Medicine, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, New York, New York
| | - Kevin C Ma
- Division of Pulmonary and Critical Care Medicine, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, New York, New York
| | - Augustine M K Choi
- Division of Pulmonary and Critical Care Medicine, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, New York, New York
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57
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Huang SL, Fu DL, Li HC, Zhang P, Chong T. The effect of rapamycin on TGFβ1 and MMP1 expression in a rabbit model of urethral stricture. Int Urol Nephrol 2016; 48:717-23. [PMID: 26837772 DOI: 10.1007/s11255-016-1227-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 01/22/2016] [Indexed: 11/25/2022]
Abstract
PURPOSE To investigate the effect of rapamycin on TGFβ1 and MMP1 expression in a rabbit model of urethral stricture. METHODS Twenty-four adult New Zealand male rabbits underwent an electrocoagulation of the bulbar urethra with a 13Fr pediatric resectoscope. Then rabbits were randomly divided into three groups: (1) normal control group: normal saline (NS), (2) the vehicle control group: dimethyl sulfoxide (DMSO), and (3) the treatment group: effective-dose rapamycin in DMSO (Ra), with 12, 6, and 6 rabbits in each group, respectively. Drugs were given by urethral irrigation daily for 4 weeks. Urethral tissue was harvested for histological and molecular analyses. TGFβ1 and MMP1 expression levels were evaluated by real-time quantitative PCR and immunohistochemistry. RESULTS Ten, six, and six rabbits were evaluated finally in Ra, DMSO, and NS group, respectively. Histological examination revealed the distribution of fibrosis and the degree of collagen deposition in the Ra group were smaller and slighter than the two control groups. Collagen content was significantly less in the Ra group than in the DMSO group (P < 0.001) and the NS group (P < 0.001). qRT-PCR analysis showed a higher expression of MMP1 mRNA in the Ra group than in the DMSO group (P < 0.001) and the NS group (P < 0.001). Immunohistochemistry showed the protein levels of MMP1 in the Ra group were significantly increased when compared with the DMSO group (P < 0.01) and the NS group (P < 0.01). On the other hand, no statistical difference could be found between every two groups in both mRNA and protein levels of TGFβ1. CONCLUSIONS Rapamycin enhances the expression of MMP1 in a rabbit model of urethral stricture, but has no direct effect on the expression of TGFβ1.
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Affiliation(s)
- S L Huang
- Department of Urology, the Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an City, 710004, Shaanxi Province, People's Republic of China
| | - D L Fu
- Department of Urology, the Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an City, 710004, Shaanxi Province, People's Republic of China
| | - H C Li
- Department of Urology, the Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an City, 710004, Shaanxi Province, People's Republic of China
| | - P Zhang
- Department of Urology, the Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an City, 710004, Shaanxi Province, People's Republic of China
| | - T Chong
- Department of Urology, the Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an City, 710004, Shaanxi Province, People's Republic of China.
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58
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Sadowski K, Kotulska K, Jóźwiak S. Management of side effects of mTOR inhibitors in tuberous sclerosis patients. Pharmacol Rep 2016; 68:536-42. [PMID: 26891243 DOI: 10.1016/j.pharep.2016.01.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Revised: 01/07/2016] [Accepted: 01/08/2016] [Indexed: 01/20/2023]
Abstract
mTOR inhibitors represent a relatively new therapeutic option in the management of patients affected by tuberous sclerosis complex (TSC). Randomized clinical trials support the use of everolimus in the treatment of subependymal giant cell astrocytomas (SEGA) and renal angiomyolipomas (AML) related to TSC. Accumulating data suggest also systemic disease-modifying potential of mTOR inhibitors. Given that increasing number of patients with TSC receive mTOR inhibitors, the issue of adverse events associated with this therapy becomes practically important. In the present study we provide the overview of clinical manifestations and therapeutic options for the most common adverse events related to mTOR inhibitors in TSC patients.
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Affiliation(s)
- Krzysztof Sadowski
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warszawa, Poland.
| | - Katarzyna Kotulska
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warszawa, Poland.
| | - Sergiusz Jóźwiak
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warszawa, Poland; Department of Pediatric Neurology, Warsaw Medical University, Warszawa, Poland.
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Abstract
Mechanistic target of rapamycin (mTOR, also known as mammalian target of rapamycin) is a ubiquitous serine/threonine kinase that regulates cell growth, proliferation and survival. These effects are cell-type-specific, and are elicited in response to stimulation by growth factors, hormones and cytokines, as well as to internal and external metabolic cues. Rapamycin was initially developed as an inhibitor of T-cell proliferation and allograft rejection in the organ transplant setting. Subsequently, its molecular target (mTOR) was identified as a component of two interacting complexes, mTORC1 and mTORC2, that regulate T-cell lineage specification and macrophage differentiation. mTORC1 drives the proinflammatory expansion of T helper (TH) type 1, TH17, and CD4(-)CD8(-) (double-negative, DN) T cells. Both mTORC1 and mTORC2 inhibit the development of CD4(+)CD25(+)FoxP3(+) T regulatory (TREG) cells and, indirectly, mTORC2 favours the expansion of T follicular helper (TFH) cells which, similarly to DN T cells, promote B-cell activation and autoantibody production. In contrast to this proinflammatory effect of mTORC2, mTORC1 favours, to some extent, an anti-inflammatory macrophage polarization that is protective against infections and tissue inflammation. Outside the immune system, mTORC1 controls fibroblast proliferation and chondrocyte survival, with implications for tissue fibrosis and osteoarthritis, respectively. Rapamycin (which primarily inhibits mTORC1), ATP-competitive, dual mTORC1/mTORC2 inhibitors and upstream regulators of the mTOR pathway are being developed to treat autoimmune, hyperproliferative and degenerative diseases. In this regard, mTOR blockade promises to increase life expectancy through treatment and prevention of rheumatic diseases.
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Affiliation(s)
- Andras Perl
- Division of Rheumatology, Departments of Medicine, Microbiology and Immunology, and Biochemistry and Molecular Biology, State University of New York, Upstate Medical University, College of Medicine, 750 East Adams Street, Syracuse, New York 13210, USA
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60
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Bernard M, Dieudé M, Yang B, Hamelin K, Underwood K, Hébert MJ. Autophagy fosters myofibroblast differentiation through MTORC2 activation and downstream upregulation of CTGF. Autophagy 2015; 10:2193-207. [PMID: 25495560 PMCID: PMC4502773 DOI: 10.4161/15548627.2014.981786] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Recent evidence suggests that autophagy may favor fibrosis through enhanced differentiation of fibroblasts in myofibroblasts. Here, we sought to characterize the mediators and signaling pathways implicated in autophagy-induced myofibroblast differentiation. Fibroblasts, serum starved for up to 4 d, showed increased LC3-II/-I ratios and decreased SQSTM1/p62 levels. Autophagy was associated with acquisition of markers of myofibroblast differentiation including increased protein levels of ACTA2/αSMA (actin, α 2, smooth muscle, aorta), enhanced gene and protein levels of COL1A1 (collagen, type I, α 1) and COL3A1, and the formation of stress fibers. Inhibiting autophagy with 3 different class I phosphoinositide 3-kinase and class III phosphatidylinositol 3-kinase (PtdIns3K) inhibitors or through ATG7 silencing prevented myofibroblast differentiation. Autophagic fibroblasts showed increased expression and secretion of CTGF (connective tissue growth factor), and CTGF silencing prevented myofibroblast differentiation. Phosphorylation of the MTORC1 target RPS6KB1/p70S6K kinase was abolished in starved fibroblasts. Phosphorylation of AKT at Ser473, a MTORC2 target, was reduced after initiation of starvation but was followed by spontaneous rephosphorylation after 2 d of starvation, suggesting the reactivation of MTORC2 with sustained autophagy. Inhibiting MTORC2 activation with long-term exposure to rapamycin or by silencing RICTOR, a central component of the MTORC2 complex abolished AKT rephosphorylation. Both RICTOR silencing and rapamycin treatment prevented CTGF and ACTA2 upregulation, demonstrating the central role of MTORC2 activation in CTGF induction and myofibroblast differentiation. Finally, inhibition of autophagy with PtdIns3K inhibitors or ATG7 silencing blocked AKT rephosphorylation. Collectively, these results identify autophagy as a novel activator of MTORC2 signaling leading to CTGF induction and myofibroblast differentiation.
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Key Words
- 3-MA, 3-methyladenine
- ACTA2, actin, α 2, smooth muscle, aorta
- AKT
- ATG7
- Ctl, control
- DAPI, 4′, 6-diamidino-2-phenylindole
- ECM, extracellular matrix
- FBS, fetal bovine serum
- GF, growth factor
- LC3B, MAP1LC3B (microtubule-associated protein 1 light chain 3 β)
- LY, LY294002
- MTORC2
- N, normal growth medium
- R, rapamycin
- SS, serum-free (starvation) medium
- T, TGFB1 (transforming growth factor, β 1)
- TUBA, tubulin, α
- V, vehicle
- W, wortmannin
- WB, western blotting
- autophagy
- connective tissue growth factor (CTGF)
- differentiation
- fibroblast
- fibrosis
- iso, isotype control
- myofibroblast
- rapamycin
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Affiliation(s)
- Monique Bernard
- a Centre de Recherche du Hospitalier de l'Université de Montréal (CRCHUM) and Université de Montréal ; Montreal , QC , Canada
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Gui YS, Wang L, Tian X, Li X, Ma A, Zhou W, Zeng N, Zhang J, Cai B, Zhang H, Chen JY, Xu KF. mTOR Overactivation and Compromised Autophagy in the Pathogenesis of Pulmonary Fibrosis. PLoS One 2015; 10:e0138625. [PMID: 26382847 PMCID: PMC4575195 DOI: 10.1371/journal.pone.0138625] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Accepted: 08/31/2015] [Indexed: 01/13/2023] Open
Abstract
The mammalian target of rapamycin (mTOR) signaling pathway in pulmonary fibrosis was investigated in cell and animal models. mTOR overactivation in alveolar epithelial cells (AECs) was achieved in the conditional and inducible Tsc1 knock-down mice SPC-rtTA/TetO-Cre/Tsc1fx/+ (STT). Doxycycline caused Tsc1 knock-down and consequently mTOR activation in AECs for the STT mice. Mice treated with bleomycin exhibited increased mortality and pulmonary fibrosis compared with control mice. In wild-type C57BL/6J mice, pretreatment with rapamycin attenuated the bleomycin-mediated mortality and fibrosis. Rapamycin-mediated mouse survival benefit was inhibited by chloroquine, an autophagy inhibitor. Autophagosomes were decreased in the lungs after bleomycin exposure. Rapamycin induced the production of autophagosomes and diminished p62. We concluded that mTOR overactivation in AECs and compromised autophagy in the lungs are involved in the pathogenesis of pulmonary fibrosis. The suppression of mTOR and enhancement of autophagy may be used for treatment of pulmonary fibrosis.
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Affiliation(s)
- Yao-Song Gui
- Department of Respiratory Medicine, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Lianmei Wang
- State Key Laboratory of Medical Molecular Biology, Department of Physiology and Pathophysiology, Institute of Basic Medical Sciences, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| | - Xinlun Tian
- Department of Respiratory Medicine, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Xue Li
- Department of Respiratory Medicine, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Aiping Ma
- Department of Respiratory Medicine, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Weixun Zhou
- Department of Pathology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Ni Zeng
- Department of Respiratory Medicine, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Ji Zhang
- Department of Thoracic Surgery, Wuxi People’s Hospital affiliated to Nanjing Medical University, Wuxi, China
| | - Baiqiang Cai
- Department of Respiratory Medicine, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Hongbing Zhang
- State Key Laboratory of Medical Molecular Biology, Department of Physiology and Pathophysiology, Institute of Basic Medical Sciences, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Jing-Yu Chen
- Department of Thoracic Surgery, Wuxi People’s Hospital affiliated to Nanjing Medical University, Wuxi, China
- * E-mail: (JYC); (KFX)
| | - Kai-Feng Xu
- Department of Respiratory Medicine, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
- * E-mail: (JYC); (KFX)
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Dual mTOR Inhibition Is Required to Prevent TGF-β-Mediated Fibrosis: Implications for Scleroderma. J Invest Dermatol 2015; 135:2873-2876. [PMID: 26134944 PMCID: PMC4640976 DOI: 10.1038/jid.2015.252] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Chu H, Wu T, Wu W, Tu W, Jiang S, Chen S, Ma Y, Liu Q, Zhou X, Jin L, Wang J. Involvement of collagen-binding heat shock protein 47 in scleroderma-associated fibrosis. Protein Cell 2015; 6:589-598. [PMID: 26091621 PMCID: PMC4506285 DOI: 10.1007/s13238-015-0171-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Accepted: 04/27/2015] [Indexed: 02/03/2023] Open
Abstract
Uncontrolled fibrosis of skin and internal organs is the main characteristic of scleroderma, and collagen is a major extracellular matrix protein that deposits in the fibrotic organs. As the chaperone of collagen, heat shock protein 47 (HSP47) is closely related with the development of fibrosis. To explore the potential function of HSP47 in the pathogenesis of scleroderma, the clinical, in vivo and in vitro studies were performed. In clinical, the increased mRNA level of HSP47 was observed in the skin fibroblasts and PBMC from scleroderma patients, and the enhanced protein level of HSP47 was also detected in the skin biopsy and plasma of the above patients. Unexpectedly, the enhanced levels of HSP47 were positively correlated with the presence of anti-centromere antibody in scleroderma patients. Moreover, a high expression of HSP47 was found in the skin lesion of BLM-induced scleroderma mouse model. Further in vitro studies demonstrated that HSP47 knockdown could block the intracellular and extracellular collagen over-productions induced by exogenous TGF-β. Therefore, the results in this study provide direct evidence that HSP47 is involved in the pathogenesis of scleroderma. The high expression of HSP47 can be detected in the circulatory system of scleroderma patients, indicating that HSP47 may become a pathological marker to assess the progression of scleroderma, and also explain the systemic fibrosis of scleroderma. Meanwhile, collagen over-expression is blocked by HSP47 knockdown, suggesting the possibility that HSP47 can be a potential therapeutic target for scleroderma.
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Affiliation(s)
- Haiyan Chu
- />Ministry of Education Key Laboratory of Contemporary Anthropology and State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200438 China
| | - Ting Wu
- />Ministry of Education Key Laboratory of Contemporary Anthropology and State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200438 China
| | - Wenyu Wu
- />Division of Dermatology, Huashan Hospital, Fudan University, Shanghai, 200040 China
- />Institute of Rheumatology, Immunology and Allergy, Fudan University, Shanghai, 20080 China
| | - Wenzhen Tu
- />Division of Rheumatology, Shanghai TCM-Integrated Hospital, Shanghai, 200082 China
| | - Shuai Jiang
- />Ministry of Education Key Laboratory of Contemporary Anthropology and State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200438 China
| | - Sidi Chen
- />Ministry of Education Key Laboratory of Contemporary Anthropology and State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200438 China
| | - Yanyun Ma
- />Ministry of Education Key Laboratory of Contemporary Anthropology and State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200438 China
| | - Qingmei Liu
- />Ministry of Education Key Laboratory of Contemporary Anthropology and State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200438 China
| | - Xiaodong Zhou
- />Division of Rheumatology, University of Texas Health Science Center at Houston, Houston, TX 77030 USA
| | - Li Jin
- />Ministry of Education Key Laboratory of Contemporary Anthropology and State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200438 China
| | - Jiucun Wang
- />Ministry of Education Key Laboratory of Contemporary Anthropology and State Key Laboratory of Genetic Engineering, Collaborative Innovation Center for Genetics and Development, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200438 China
- />Institute of Rheumatology, Immunology and Allergy, Fudan University, Shanghai, 20080 China
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Ponticos M, Papaioannou I, Xu S, Holmes AM, Khan K, Denton CP, Bou-Gharios G, Abraham DJ. Failed degradation of JunB contributes to overproduction of type I collagen and development of dermal fibrosis in patients with systemic sclerosis. Arthritis Rheumatol 2015; 67:243-53. [PMID: 25303440 PMCID: PMC4312903 DOI: 10.1002/art.38897] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 09/25/2014] [Indexed: 12/31/2022]
Abstract
OBJECTIVE The excessive deposition of extracellular matrix, including type I collagen, is a key aspect in the pathogenesis of connective tissue diseases such as systemic sclerosis (SSc; scleroderma). To further our understanding of the mechanisms governing the dysregulation of type I collagen production in SSc, we investigated the role of the activator protein 1 (AP-1) family of transcription factors in regulating COL1A2 transcription. METHODS The expression and nuclear localization of AP-1 family members (c-Jun, JunB, JunD, Fra-1, Fra-2, and c-Fos) were examined by immunohistochemistry and Western blotting in dermal biopsy specimens and explanted skin fibroblasts from patients with diffuse cutaneous SSc and healthy controls. Gene activation was determined by assessing the interaction of transcription factors with the COL1A2 enhancer using transient transfection of reporter gene constructs, electrophoretic mobility shift assays, chromatin immunoprecipitation analysis, and RNA interference involving knockdown of individual AP-1 family members. Inhibition of fibroblast mammalian target of rapamycin (mTOR), Akt, and glycogen synthase kinase 3β (GSK-3β) signaling pathways was achieved using small-molecule pharmacologic inhibitors. RESULTS Binding of JunB to the COL1A2 enhancer was observed, with its coalescence directed by activation of gene transcription through the proximal promoter. Knockdown of JunB reduced enhancer activation and COL1A2 expression in response to transforming growth factor β. In SSc dermal fibroblasts, increased mTOR/Akt signaling was associated with inactivation of GSK-3β, leading to blockade of JunB degradation and, thus, constitutively high expression of JunB. CONCLUSION In patients with SSc, the accumulation of JunB resulting from altered mTOR/Akt signaling and a failure of proteolytic degradation underpins the aberrant overexpression of type I collagen. These findings identify JunB as a potential target for antifibrotic therapy in SSc.
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The Tumor Necrosis Factor Superfamily Molecule LIGHT Promotes Keratinocyte Activity and Skin Fibrosis. J Invest Dermatol 2015; 135:2109-2118. [PMID: 25789702 PMCID: PMC4504809 DOI: 10.1038/jid.2015.110] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/19/2015] [Accepted: 03/06/2015] [Indexed: 01/10/2023]
Abstract
Several inflammatory diseases including scleroderma and atopic dermatitis display dermal thickening, epidermal hypertrophy, or excessive accumulation of collagen. Factors that might promote these features are of interest for clinical therapy. We previously reported that LIGHT, a TNF superfamily molecule, mediated collagen deposition in the lungs in response to allergen. We therefore tested whether LIGHT might similarly promote collagen accumulation and features of skin fibrosis. Strikingly, injection of recombinant soluble LIGHT into naive mice, either subcutaneously or systemically, promoted collagen deposition in the skin and dermal and epidermal thickening. This replicated the activity of bleomycin, an antibiotic that has been previously used in models of scleroderma in mice. Moreover skin fibrosis induced by bleomycin was dependent on endogenous LIGHT activity. The action of LIGHT in vivo was mediated via both of its receptors, HVEM and LTβR, and was dependent on the innate cytokine TSLP and TGF-β. Furthermore, we found that HVEM and LTβR were expressed on human epidermal keratinocytes and that LIGHT could directly promote TSLP expression in these cells. We reveal an unappreciated activity of LIGHT on keratinocytes and suggest that LIGHT may be an important mediator of skin inflammation and fibrosis in diseases such as scleroderma or atopic dermatitis.
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66
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Abstract
Osteoarthritis (OA) is a chronic degenerative joint disease characterized by the progressive loss of articular cartilage, remodeling of the subchondral bone, and synovial inflammation. Mammalian target of rapamycin (mTOR) is a serine/threonine protein kinase that controls critical cellular processes such as growth, proliferation, and protein synthesis. Recent studies suggest that mTOR plays a vital role in cartilage growth and development and in altering the articular cartilage homeostasis as well as contributing to the process of cartilage degeneration associated with OA. Both pharmacological inhibition and genetic deletion of mTOR have been shown to reduce the severity of OA in preclinical mouse models. In this review article, we discuss the roles of mTOR in cartilage development, in maintaining articular cartilage homeostasis, and its potential as an OA therapeutic target.
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Affiliation(s)
- Bandna Pal
- Division of Genetics and Development, The Toronto Western Research Institute, Toronto Western Hospital, The University Health Network (UHN), 60 Leonard Avenue, Toronto, ON M5T 2S8 Canada
| | - Helal Endisha
- Division of Genetics and Development, The Toronto Western Research Institute, Toronto Western Hospital, The University Health Network (UHN), 60 Leonard Avenue, Toronto, ON M5T 2S8 Canada
| | - Yue Zhang
- Division of Genetics and Development, The Toronto Western Research Institute, Toronto Western Hospital, The University Health Network (UHN), 60 Leonard Avenue, Toronto, ON M5T 2S8 Canada
| | - Mohit Kapoor
- Division of Genetics and Development, The Toronto Western Research Institute, Toronto Western Hospital, The University Health Network (UHN), 60 Leonard Avenue, Toronto, ON M5T 2S8 Canada
- Department of Surgery, University of Toronto, Toronto, ON Canada
- Division of Orthopaedics, Toronto Western Hospital, Toronto, ON Canada
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67
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Luo L, Zhang C, Zhao J, Wei Q, Li X. Effects of rapamycin on reduction of peridural fibrosis: an experimental study. Med Sci Monit 2015; 21:482-8. [PMID: 25677111 PMCID: PMC4335565 DOI: 10.12659/msm.893165] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background Peridural fibrosis (PF) is a normal complication after lumbar surgery. It is a challenge for both surgeons and patients. Rapamycin (RPM), a novel antibiotic with anti-proliferative and immunosuppressive properties, has been shown to be effective in preventing uncontrolled scar proliferation diseases. The object of the present research was to investigate the effects of RPM on inhibiting PF in vitro and in vivo. Material/Methods In vitro, the fibroblasts collected and isolated from the rat tail skin were cultured with/without RPM and cell counting was performed. In vivo, the double-blinded study was conducted in 60 healthy Wistar rats divided randomly into 3 groups: 1) RPM treatment group; 2) Vehicle treatment group; 3) Control group. Rats underwent a L1-L2 level laminectomy with a satisfactory anesthetization. Four weeks post-operatively, the Rydell score, histological analysis, hydroxyproline content, vimentin expressional level, and inflammatory cytokines expressional levels were assessed. Results In vitro, RPM showed ability to prevent fibroblast proliferation. In vivo, the laminectomy was well tolerated by all rats, which were killed 4 weeks post-operatively. The Rydell score, histological evaluation, hydroxyproline content, vimentin expression level, and inflammatory activity showed the positive effect of RPM in preventing peridural adhesion, inhibiting fibrotic formation and collagen synthesis, and down-regulating inflammation. Conclusions In the present primary study, RPM showed good efficacy in preventing the proliferation of fibroblasts. RPM can prevent rat peridural adhesion through inhibiting collagen synthesis, fibroblasts proliferation, and inflammatory activity.
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Affiliation(s)
- Like Luo
- Department of Orthopedic Trauma and Hand Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Chifei Zhang
- Affiliated Tumor Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Jinmin Zhao
- Department of Orthopedic Trauma and Hand Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Qingjun Wei
- Department of Orthopedic Trauma and Hand Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Xiaofeng Li
- Department of Orthopedic Trauma and Hand Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China (mainland)
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Transcriptional profiling of rapamycin-treated fibroblasts from hypertrophic and keloid scars. Ann Plast Surg 2015; 72:711-9. [PMID: 24835866 DOI: 10.1097/sap.0b013e31826956f6] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Excess scar formation after cutaneous injury can result in hypertrophic scar (HTS) or keloid formation. Modern strategies to treat pathologic scarring represent nontargeted approaches that produce suboptimal results. Mammalian target of rapamycin (mTOR), a central mediator of inflammation, has been proposed as a novel target to block fibroproliferation. To examine its mechanism of action, we performed genomewide microarray on human fibroblasts (from normal skin, HTS, and keloid scars) treated with the mTOR inhibitor, rapamycin. Hypertrophic scar and keloid fibroblasts demonstrated overexpression of collagen I and III that was effectively abrogated with rapamycin. Blockade of mTOR specifically impaired fibroblast expression of the collagen biosynthesis genes PLOD, PCOLCE, and P4HA, targets significantly overexpressed in HTS and keloid scars. These data suggest that pathologic scarring can be abrogated via modulation of mTOR pathways in procollagen and collagen processing.
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69
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Chen C, Akiyama K, Wang D, Xu X, Li B, Moshaverinia A, Brombacher F, Sun L, Shi S. mTOR inhibition rescues osteopenia in mice with systemic sclerosis. ACTA ACUST UNITED AC 2014; 212:73-91. [PMID: 25534817 PMCID: PMC4291526 DOI: 10.1084/jem.20140643] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Chen et al. show that treatment with rapamycin, a drug known to inhibit mTOR signaling, rescues low bone density in mice with systemic sclerosis. Fibrillin-1 (FBN1) deficiency-induced systemic sclerosis is attributed to elevation of interleukin-4 (IL4) and TGF-β, but the mechanism underlying FBN1 deficiency–associated osteopenia is not fully understood. We show that bone marrow mesenchymal stem cells (BMMSCs) from FBN1-deficient (Fbn1+/−) mice exhibit decreased osteogenic differentiation and increased adipogenic differentiation. Mechanistically, this lineage alteration is regulated by IL4/IL4Rα-mediated activation of mTOR signaling to down-regulate RUNX2 and up-regulate PPARγ2, respectively, via P70 ribosomal S6 protein kinase (P70S6K). Additionally, we reveal that activation of TGF-β/SMAD3/SP1 signaling results in enhancement of SP1 binding to the IL4Rα promoter to synergistically activate mTOR pathway in Fbn1+/− BMMSCs. Blockage of mTOR signaling by osteoblastic-specific knockout or rapamycin treatment rescues osteopenia phenotype in Fbn1+/− mice by improving osteogenic differentiation of BMMSCs. Collectively, this study identifies a previously unrecognized role of the FBN1/TGF-β/IL4Rα/mTOR cascade in BMMSC lineage selection and provides experimental evidence that rapamycin treatment may provide an anabolic therapy for osteopenia in Fbn1+/− mice.
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Affiliation(s)
- Chider Chen
- Center for Craniofacial Molecular Biology, Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033 Department of Anatomy and Cell Biology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Kentaro Akiyama
- Center for Craniofacial Molecular Biology, Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033 Department of Oral Rehabilitation and Regenerative Medicine, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Science, Kita-ku, Okayama 700-8525, Japan
| | - Dandan Wang
- Department of Rheumatology and Immunology, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008, China
| | - Xingtian Xu
- Center for Craniofacial Molecular Biology, Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033 Key Laboratory of Translational Research, Tong Ji University School of Stomatology, Shanghai 200072, China
| | - Bei Li
- Center for Craniofacial Molecular Biology, Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033 School of Stomatology, Fourth Military Medical University, Xi'an 710032, Shaanxi, China
| | - Alireza Moshaverinia
- Center for Craniofacial Molecular Biology, Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033
| | - Frank Brombacher
- Division of Immunology, Cape Town Component and Institute of Infectious Diseases and Molecular Medicine (IIDMM), International Center for Genetic Engineering and Biotechnology (ICGEB) University of Cape Town, Cape Town 7925, South Africa
| | - Lingyun Sun
- Department of Rheumatology and Immunology, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008, China
| | - Songtao Shi
- Center for Craniofacial Molecular Biology, Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033
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Zhang W, Chen G, Ren JG, Zhao YF. Bleomycin induces endothelial mesenchymal transition through activation of mTOR pathway: a possible mechanism contributing to the sclerotherapy of venous malformations. Br J Pharmacol 2014; 170:1210-20. [PMID: 23992520 DOI: 10.1111/bph.12355] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2013] [Revised: 07/29/2013] [Accepted: 08/19/2013] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE Bleomycin (BLM), one of the most common sclerosants, is often used to treat venous malformations (VMs). The present study was designed to investigate whether endothelial mesenchymal transition (EndoMT) contributes to the therapeutic effects of BLM. EXPERIMENTAL APPROACH Endothelial and mesenchymal markers of HUVECs were measured by immunofluorescence, real-time quantitative PCR and Western blot analysis. Cell migration and tube formation assays were performed to evaluate endothelial cell function. Slug small-interfering RNA and specific inhibitors [Z-VAD-FMK for pan caspases, rapamycin for mammalian target of rapamycin (mTOR)] were used to investigate the mechanism. KEY RESULTS Long term (48 h or longer) treatment with BLM (0.1 mU·mL(-1) ) induced EndoMT in HUVECs, as manifested by a reduction in the expression of vascular endothelial-cadherin and an up-regulation in the expression of α-smooth muscle actin and fibroblast specific protein-1, as well as activation of the transcription factor Slug. The size and protein content of the transformed cells were increased. BLM also enhanced the migration of HUVECs but diminished their tube formation. By employing rapamycin, we demonstrated that activation of the mTOR pathway is involved in BLM-induced EndoMT in HUVECs. CONCLUSIONS AND IMPLICATIONS Our results show that a Slug-dependent EndoMT process is involved in BLM-induced therapeutic effects on endothelial cells and, more importantly, indicate the potential role of this process in the sclerotherapy of VMs.
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Affiliation(s)
- Wei Zhang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China; Department of Oral & Maxillofacial - Head & Neck Oncology, School and Hospital of Stomatology, Wuhan University, Wuhan, China
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Liang M, Lv J, Chu H, Wang J, Chen X, Zhu X, Xue Y, Guan M, Zou H. Vertical inhibition of PI3K/Akt/mTOR signaling demonstrates in vitro and in vivo anti-fibrotic activity. J Dermatol Sci 2014; 76:104-11. [PMID: 25258031 DOI: 10.1016/j.jdermsci.2014.08.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 07/01/2014] [Accepted: 08/05/2014] [Indexed: 02/07/2023]
Abstract
BACKGROUND The mammalian target of rapamycin (mTOR) regulates cellular activity in many diseases, but the complex interplay with PI3K/Akt pathway may hampers its function. OBJECTIVE This study was undertaken to determine the activity of PI3K/Akt/mTOR signaling in the fibroblasts from systemic sclerosis (SSc) patients, and compare the effects of vertical inhibiting PI3K/Akt/mTOR by BEZ235 and inhibiting mTOR alone by rapamycin in fibroblast activation and in two complementary established mouse model of SSc. METHODS Pharmaceutical specific inhibitors BEZ235 and rapamycin were used to vertical inhibit PI3K/Akt/mTOR signaling and mTOR signaling alone in cultured fibroblasts and in mice. SSc mouse model was established by daily injecting bleomycin subcutaneously or by overexpression of constitutively active type I TGF-β receptor (TβRI(ca)). To delineate the mechanisms underlying the antifibrotic effects of BEZ235 and rapamycin, activity of PI3K/Akt/mTOR signaling was analyzed by determining the expressions of phosphorylated Akt, GSK-3β, mTOR and S6 ribosomal protein (S6). RESULTS Primary dermal fibroblasts demonstrated hyperactivity of PI3K/Akt and mTOR signaling. mTOR inhibitor rapamycin failed to inhibit dermal fibrosis in an established SSc mouse model. However, administration of a dual inhibitor for PI3K/Akt and mTOR signaling BEZ235 attenuated dermal fibrosis by reversing increased dermal thickness and collagen deposition in two SSc mouse models. Furthermore, BEZ235 showed superior inhibitory effect on fibroblast activation relative to rapamycin in vitro. Also both BEZ235 and rapamycin could prevent the phosphorylation of mTOR and S6 completely. BEZ235 also blocked the activation of Akt and GSK-3β dramatically, whereas rapamycin has been shown to increase further upregulation of phosphorylated Akt on Ser473 both in vitro and in vivo. CONCLUSION These data show that blocking PI3K/Akt/mTOR with BEZ235 leads to superior inhibitory effect for dermal fibrosis, suggesting that vertical inhibition of PI3K/Akt/mTOR signaling may have therapeutic potential for SSc.
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Affiliation(s)
- Minrui Liang
- Division of Rheumatology, Huashan Hospital, Shanghai 200040, China; Institute of Rheumatology, Immunology and Allergy, Fudan University, Shanghai 200040, China
| | - Jiaoyan Lv
- Department of Immunology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Haiyan Chu
- Institute of Rheumatology, Immunology and Allergy, Fudan University, Shanghai 200040, China; Ministry of Education Key Laboratory of Contemporary Anthropology and State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Jiucun Wang
- Institute of Rheumatology, Immunology and Allergy, Fudan University, Shanghai 200040, China; Ministry of Education Key Laboratory of Contemporary Anthropology and State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200433, China
| | - Xiangjun Chen
- Institute of Rheumatology, Immunology and Allergy, Fudan University, Shanghai 200040, China; Department of Neurology, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Xiaoxia Zhu
- Division of Rheumatology, Huashan Hospital, Shanghai 200040, China; Institute of Rheumatology, Immunology and Allergy, Fudan University, Shanghai 200040, China
| | - Yu Xue
- Division of Rheumatology, Huashan Hospital, Shanghai 200040, China; Institute of Rheumatology, Immunology and Allergy, Fudan University, Shanghai 200040, China
| | - Ming Guan
- Institute of Rheumatology, Immunology and Allergy, Fudan University, Shanghai 200040, China; Department of Clinical Laboratory, Huashan Hospital, Fudan University, Shanghai 200040, China
| | - Hejian Zou
- Division of Rheumatology, Huashan Hospital, Shanghai 200040, China; Institute of Rheumatology, Immunology and Allergy, Fudan University, Shanghai 200040, China.
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Abstract
Without doubt, animal models have provided significant insights into our understanding of the rheumatological diseases; however, no model has accurately replicated all aspects of any autoimmune disease. Recent years have seen a plethora of knockouts and transgenics that have contributed to our knowledge of the initiating events of systemic sclerosis, an autoimmune disease. In this review, the focus is on models of systemic sclerosis and how they have progressed our understanding of fibrosis and vasculopathy, and whether they are relevant to the pathogenesis of systemic sclerosis.
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Affiliation(s)
- Carol M Artlett
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA, USA
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Tamaki Z, Asano Y, Kubo M, Ihn H, Tada Y, Sugaya M, Kadono T, Sato S. Effects of the immunosuppressant rapamycin on the expression of human α2(I) collagen and matrix metalloproteinase 1 genes in scleroderma dermal fibroblasts. J Dermatol Sci 2014; 74:251-9. [PMID: 24630239 DOI: 10.1016/j.jdermsci.2014.02.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Revised: 11/28/2013] [Accepted: 02/03/2014] [Indexed: 01/10/2023]
Abstract
BACKGROUND Rapamycin has been shown to exert an anti-fibrotic effect on skin fibrosis in a certain subset of patients with systemic sclerosis (SSc) and in bleomycin-treated animal models. OBJECTIVES To investigate the mechanism responsible for the anti-fibrotic effect of rapamycin especially by focusing on human α2(I) collagen (COL1A2) and matrix metalloproteinase 1 (MMP1) genes in normal and systemic sclerosis (SSc) dermal fibroblasts. METHODS The expression levels of type I procollagen and MMP1 proteins were analyzed by immunoblotting and the mRNA levels of COL1A2 and MMP1 genes were evaluated by quantitative real-time RT-PCR. The activities of COL1A2 and MMP1 promoters were determined by reporter analysis. RESULTS Rapamycin significantly decreased the levels of type I procollagen protein and COL1A2 mRNA, while significantly increasing the levels of MMP1 protein and mRNA in normal dermal fibroblasts. Similar effects of rapamycin were also observed in SSc dermal fibroblasts. Importantly, the inhibitory and stimulatory effects of rapamycin on the mRNA levels of COL1A2 and MMP1 genes, respectively, were significantly greater in SSc dermal fibroblasts than in normal dermal fibroblasts. In SSc dermal fibroblasts, rapamycin affected the expression of COL1A2 gene at the post-transcriptional level. In contrast, rapamycin altered the expression of MMP1 gene at the transcriptional level through the JNK/c-Jun signaling pathway in those cells. CONCLUSION Rapamycin has a potential to directly regulate the deposition of type I collagen in extracellular matrix through inhibiting type I collagen synthesis and promoting its degradation by MMP1, suggesting that this drug is useful for the treatment of SSc.
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Affiliation(s)
- Zenshiro Tamaki
- Department of Dermatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Yoshihide Asano
- Department of Dermatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan.
| | - Masahide Kubo
- Department of Dermatology, Tokyo Kousei-Nenkin Hospital, Tokyo, Japan
| | - Hironobu Ihn
- Department of Dermatology and Plastic Surgery, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Yayoi Tada
- Department of Dermatology, Teikyo University School of Medicine, Tokyo, Japan
| | - Makoto Sugaya
- Department of Dermatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Takafumi Kadono
- Department of Dermatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Shinichi Sato
- Department of Dermatology, University of Tokyo Graduate School of Medicine, Tokyo, Japan
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Arno AI, Gauglitz GG, Barret JP, Jeschke MG. New molecular medicine-based scar management strategies. Burns 2014; 40:539-51. [PMID: 24438742 DOI: 10.1016/j.burns.2013.11.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 10/21/2013] [Accepted: 11/18/2013] [Indexed: 02/06/2023]
Abstract
Keloids and hypertrophic scars are prevalent disabling conditions with still suboptimal treatments. Basic science and molecular-based medicine research have contributed to unravel new bench-to-bedside scar therapies and to dissect the complex signalling pathways involved. Peptides such as the transforming growth factor beta (TGF-β) superfamily, with Smads, Ski, SnoN, Fussels, endoglin, DS-Sily, Cav-1p, AZX100, thymosin-β4 and other related molecules may emerge as targets to prevent and treat keloids and hypertrophic scars. The aim of this review is to describe the basic complexity of these new molecular scar management strategies and point out new fibrosis research lines.
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Affiliation(s)
- Anna I Arno
- Ross Tilley Burn Centre and Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada; Plastic Surgery Department and Burn Unit, Vall d'Hebron University Hospital, Autonomous University of Barcelona, Barcelona, Spain
| | - Gerd G Gauglitz
- Department of Dermatology and Allergology, Ludwig Maximilians University, Munich, Germany
| | - Juan P Barret
- Plastic Surgery Department and Burn Unit, Vall d'Hebron University Hospital, Autonomous University of Barcelona, Barcelona, Spain
| | - Marc G Jeschke
- Ross Tilley Burn Centre and Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada.
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Latella G, Vetuschi A, Sferra R, Speca S, Gaudio E. Localization of ανβ6 integrin-TGF-β1/Smad3, mTOR and PPARγ in experimental colorectal fibrosis. Eur J Histochem 2013; 57:e40. [PMID: 24441193 PMCID: PMC3896042 DOI: 10.4081/ejh.2013.e40] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 11/26/2013] [Accepted: 11/04/2013] [Indexed: 02/08/2023] Open
Abstract
A simultaneous action of several pro-fibrotic mediators appears relevant in the development of fibrosis. There are evidences that transforming growth factor-β (TGF-β)/Smad3 pathway forms with αvβ6 integrin, mammalian target of Rapamycin (mTOR) and peroxisome proliferator-activated receptor-γ (PPARγ) a complex signalling network with extensive crosstalk and strong effects on fibrosis development. The present study evaluated the expression of TGFβ, Smad3, αvβ6 integrin, mTOR and PPARγ in 2, 4, 6-trinitrobenzenesulphonic acid (TNBS)-induced colorectal fibrosis in Smad3 wild-type (WT) and null mice. Smad3 WT mice treated with TNBS developed a marked colorectal fibrosis and showed a concomitant up-regulation of TGFβ, Smad3, αvβ6 and mTOR and a reduction of PPARγ expression. On the other hand, Smad3 Null mice similarly treated with TNBS did not develop fibrosis and showed a very low or even absent expression of TGFβ, Smad3, αvβ6 and mTOR and a marked over-expression of PPARγ. At the same time the expression of α-smooth muscle actin (a marker of activated myofibroblasts), collagen I-III and connective tissue growth factor (a downstream effector of TGFβ/Smad3-induced extracellular matrix proteins) were up-regulated in Smad3 WT mice treated with TNBS compared to Null TNBS-treated mice. These preliminary results suggest a possible interaction between these pro-fibrotic molecules in the development of intestinal fibrosis.
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McMahan ZH, Wigley FM. Novel investigational agents for the treatment of scleroderma. Expert Opin Investig Drugs 2013; 23:183-98. [PMID: 24261610 DOI: 10.1517/13543784.2014.848852] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
INTRODUCTION The purpose of this article is to highlight novel therapies that are being used in scleroderma (SSc). Therapeutic interventions in SSc generally target at least one of three ongoing biological processes characteristic of the disease: vasculopathy, autoimmunity and tissue fibrosis. Treatment decisions in SSc are determined by the level of disease activity and the degree of specific organ involvement. Traditional therapy has primarily focused on organ-specific management without clear evidence of overall disease modification. AREAS COVERED The authors provide a review of a variety of agents, which are already used for other autoimmune diseases, that are now being used to treat active SSc skin or lung disease, including rituximab, tocilizumab and IVIG. Several agents studied in vitro and in animal models of fibrosis have shown promise, including bortezomib, LPA-1 antagonists, anti-CCN2 therapy, anti-IL-13 and thrombin antagonists. The authors also provide details on targeting intracellular molecular pathways and matricellular proteins, which is another novel area of investigation. EXPERT OPINION Combination therapy may be necessary to control the complex biological network active in SSc. Most of the current evidence that suggest benefit of these agents is based on small population studies. Ultimately well-designed clinical trials are required to define the role of these agents in treating SSc.
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Affiliation(s)
- Zsuzsanna Hortobagyi McMahan
- Johns Hopkins University, Medicine/Rheumatology , 55200 Eastern Avenue, MFL Center Tower, Suite 5300, Baltimore, MD 21224 , USA
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Milani BY, Milani FY, Park DW, Namavari A, Shah J, Amirjamshidi H, Ying H, Djalilian AR. Rapamycin inhibits the production of myofibroblasts and reduces corneal scarring after photorefractive keratectomy. Invest Ophthalmol Vis Sci 2013; 54:7424-30. [PMID: 24106124 DOI: 10.1167/iovs.13-12674] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
PURPOSE Corneal stromal scarring partly involves the production of corneal myofibroblasts. The purpose of this study was to examine the effects of rapamycin (an inhibitor of the mammalian target of rapamycin [mTOR] pathway) on myofibroblast formation in vitro and in-vivo. METHODS Human corneal fibroblasts were grown in culture and transformed into myofibroblasts using TGF-β (2 ng/mL). The phosphorylation (activation) of the mTOR pathway was examined by immunoblotting. Cell proliferation with and without rapamycin was examined by thiazolyl blue tetrazolium bromide (MTT) assay and Ki67 staining. The expression of the myofibroblast differentiation marker smooth muscle actin (SMA) was examined by immunostaining and immunoblotting. The functional effects of rapamycin were measured using a gel contraction assay. For in vivo studies, 140 μm laser ablation was performed on rabbit corneas followed by subconjunctival rapamycin or vehicle. Corneal haze development was graded at 4 weeks, while the expression of myofibroblast markers was examined by immunostaining and immunoblotting. RESULTS The TGF-β activated the mTOR pathway with peak phosphorylation at 2 to 4 hours. Treatment of corneal fibroblasts with rapamycin reduced their proliferation by 46% compared to control. Rapamycin significantly inhibited TGF-β-induced expression of myofibroblast markers (17.2% SMA positive cells with rapamycin compared to 69.0% in control). Rapamycin also significantly inhibited TGF-β-induced collagen gel contraction. In the rabbit eyes treated with rapamycin, corneal haze development was significantly less compared to controls (0.75 ± 0.4 vs. 2.17 ± 0.7). CONCLUSIONS Rapamycin appears to inhibit proliferation and differentiation of corneal myofibroblasts and, thus, may provide an effective therapeutic measure for preventing corneal scarring.
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Affiliation(s)
- Behrad Y Milani
- Illinois Eye and Ear Infirmary, University of Illinois at Chicago (UIC) Department of Ophthalmology and Visual Sciences, Chicago, Illinois
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A reactive oxygen species-mediated, self-perpetuating loop persistently activates platelet-derived growth factor receptor α. Mol Cell Biol 2013; 34:110-22. [PMID: 24190966 DOI: 10.1128/mcb.00839-13] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The platelet-derived growth factor (PDGF) receptors (PDGFRs) are central to a spectrum of human diseases. When PDGFRs are activated by PDGF, reactive oxygen species (ROS) and Src family kinases (SFKs) act downstream of PDGFRs to enhance PDGF-mediated tyrosine phosphorylation of various signaling intermediates. In contrast to these firmly established principles of signal transduction, much less is known regarding the recently appreciated ability of ROS and SFKs to indirectly and chronically activate monomeric PDGF receptor α (PDGFRα) in the setting of a blinding condition called proliferative vitreoretinopathy (PVR). In this context, we made a series of discoveries that substantially expands our appreciation of epigenetic-based mechanisms to chronically activate PDGFRα. Vitreous, which contains growth factors outside the PDGF family but little or no PDGFs, promoted formation of a unique SFK-PDGFRα complex that was dependent on SFK-mediated phosphorylation of PDGFRα and activated the receptor's kinase activity. While vitreous engaged a total of five receptor tyrosine kinases, PDGFRα was the only one that was activated persistently (at least 16 h). Prolonged activation of PDGFRα involved mTOR-mediated inhibition of autophagy and accumulation of mitochondrial ROS. These findings reveal that growth factor-containing biological fluids, such as vitreous, are able to tirelessly activate PDGFRα by engaging a ROS-mediated, self-perpetuating loop.
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Yan JW, Wang YJ, Peng WJ, Tao JH, Wan YN, Li BZ, Mei B, Chen B, Yao H, Yang GJ, Li XP, Ye DQ, Wang J. Therapeutic potential of interleukin-17 in inflammation and autoimmune diseases. Expert Opin Ther Targets 2013; 18:29-41. [PMID: 24147601 DOI: 10.1517/14728222.2013.843669] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Interleukin-17 (IL-17) is a proinflammatory cytokine that mainly produced by T helper 17 (Th17) cells. In this article, we discussed the role of IL-17 in inflammation and autoimmune diseases, and the therapeutic strategies targeting IL-17. AREAS COVERED In this article, we discussed the proinflammatory cytokine IL-17 and IL-17 receptors signals, and their regulation. IL-17 expression was abnormal in the bacterium, virus and fungus infection, and its higher level caused the tissue inflammation. IL-17 was involved in the pathological process of autoimmune diseases, such as systemic sclerosis, rheumatoid arthritis, ankylosing spondylitis and systemic lupus erythematosus, and IL-17 has been put as a therapeutic target in the clinic. EXPERT OPINION IL-17/IL-17R signals and their application in inflammation process still need to be explored. Therapeutic strategies targeting IL-17 in autoimmune diseases ameliorated the inadequate response to anti-TNF-α therapy.
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Affiliation(s)
- Jun-Wei Yan
- Anhui Medical University, School of Public Health, Department of Epidemiology and Biostatistics , NO.81, Meishan Road, Hefei, Anhui, 230032, PR , China +86 551 65161175 ; +86 551 65161126 ;
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Lo Re S, Lison D, Huaux F. CD4+
T lymphocytes in lung fibrosis: diverse subsets, diverse functions. J Leukoc Biol 2013; 93:499-510. [DOI: 10.1189/jlb.0512261] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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Maurer B, Distler O. Emerging targeted therapies in scleroderma lung and skin fibrosis. Best Pract Res Clin Rheumatol 2013; 25:843-58. [PMID: 22265265 DOI: 10.1016/j.berh.2011.11.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 11/14/2011] [Indexed: 01/08/2023]
Abstract
Systemic sclerosis (SSc) is a multisystemic fibrotic disorder that affects the skin and internal organs. Despite an improved outcome probably reflecting a better management of disease complications, morbidity and mortality remain higher than those of patients with other connective tissue diseases. SSc is still considered incurable; however, during recent years, intensive research activities have deepened the understanding of pathogenic mechanisms and have led to the identification of cellular and molecular anti-fibrotic targets. This review article will discuss potential future targeted therapeutic options based on data from in vitro studies, experimental models of fibrosis and first human trials with focus on scleroderma skin and lung fibrosis.
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Affiliation(s)
- Britta Maurer
- Department of Rheumatology and Center of Experimental Rheumatology, University Hospital Zurich, Zurich Center of Integrative Human Physiology (ZIHP), Zurich, Switzerland
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83
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Bruck F, Belle L, Lechanteur C, de Leval L, Hannon M, Dubois S, Castermans E, Humblet-Baron S, Rahmouni S, Beguin Y, Briquet A, Baron F. Impact of bone marrow-derived mesenchymal stromal cells on experimental xenogeneic graft-versus-host disease. Cytotherapy 2013; 15:267-79. [DOI: 10.1016/j.jcyt.2012.09.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 08/25/2012] [Accepted: 09/11/2012] [Indexed: 01/29/2023]
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Yoshizaki A, Yanaba K, Ogawa A, Iwata Y, Ogawa F, Takenaka M, Shimizu K, Asano Y, Kadono T, Sato S. The specific free radical scavenger edaravone suppresses fibrosis in the bleomycin-induced and tight skin mouse models of systemic sclerosis. ACTA ACUST UNITED AC 2013; 63:3086-97. [PMID: 21618208 DOI: 10.1002/art.30470] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Patients with systemic sclerosis (SSc) exhibit enhanced production of free radicals due to ischemia and reperfusion injury following Raynaud's phenomenon, an initial clinical manifestation. Oxidative stress induces cytokine production, inflammatory cell recruitment, and tissue injury in several inflammatory diseases. The aim of this study was to examine the effect of edaravone, a free radical scavenger, on the development of fibrosis and autoimmunity in two different mouse models of SSc. METHODS The bleomycin-induced SSc model in mice and the tight skin mouse model were used to evaluate the effect of edaravone on fibrosis and immunologic abnormalities. To assess the reaction of fibroblasts to stimulation with free radicals, fibroblasts from these mice were cultured with NONOate, a nitric oxide-releasing agent, and hydrogen peroxide. RESULTS Treatment with edaravone reduced fibrosis in mice with bleomycin-induced SSc and in TSK/+ mice. The production of free radicals was also attenuated by edaravone in both models. In addition, production of fibrogenic cytokines such as interleukin-6 and transforming growth factor β1, production of anti-topoisomerase I antibody, and the degree of hypergammaglobulinemia were reduced by edaravone. Furthermore, bleomycin induced the production of H2O2 and nitric oxide from inflammatory cells, and collagen production was increased in fibroblasts cultured with H2O2 and NONOate. CONCLUSION This study is the first to show that edaravone has a significant inhibitory effect on fibrosis both in the bleomycin-induced SSc model and in TSK/+ mice. These results indicate that edaravone should be further evaluated for potential use as an antifibrotic agent in SSc.
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Affiliation(s)
- Ayumi Yoshizaki
- Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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Sekiguchi Y, Zhang J, Patterson S, Liu L, Hamada C, Tomino Y, Margetts PJ. Rapamycin inhibits transforming growth factor β-induced peritoneal angiogenesis by blocking the secondary hypoxic response. J Cell Mol Med 2012; 16:1934-45. [PMID: 22117756 PMCID: PMC3822704 DOI: 10.1111/j.1582-4934.2011.01493.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Patients with end-stage kidney disease on peritoneal dialysis often develop progressive scarring of the peritoneal tissues. This manifests as submesothelial thickening and is associated with increased vascularization that leads to ultrafiltration dysfunction. Hypoxia induces a characteristic series of responses including angiogenesis and fibrosis. We investigated the role of hypoxia in peritoneal membrane damage. An adenovirus expressing transforming growth factor (TGF) β was used to induce peritoneal fibrosis. We evaluated the effect of the mTOR inhibitor rapamycin, which has been previously shown to block hypoxia-inducible factor (HIF) 1α. We also assessed the effect of HIF1α independently using an adenovirus expressing active HIF1α. To identify the TGFβ1-independent effects of HIF1α, we expressed HIF1α in the peritoneum of mice lacking the TGFβ signalling molecule Smad3. We demonstrate that TGFβ-induced fibroproliferative tissue is hypoxic. Rapamycin did not affect the early angiogenic response, but inhibited angiogenesis and submesothelial thickening 21 days after induction of fibrosis. In primary mesothelial cell culture, rapamycin had no effect on TGFβ-induced vascular endothelial growth factor (VEGF) but did suppress hypoxia-induced VEGF. HIF1α induced submesothelial thickening and angiogenesis in peritoneal tissue. The fibrogenic effects of HIF1α were Smad3 dependent. In summary, submesothelial hypoxia may be an important secondary factor, which augments TGFβ-induced peritoneal injury. The hypoxic response is mediated partly through HIF1α and the mTOR inhibitor rapamycin blocks the hypoxic-induced angiogenic effects but does not affect the direct TGFβ-mediated fibrosis and angiogenesis.
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Affiliation(s)
- Yoshimi Sekiguchi
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
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Del Principe D, Lista P, Malorni W, Giammarioli AM. Fibroblast autophagy in fibrotic disorders. J Pathol 2012; 229:208-20. [PMID: 23018629 DOI: 10.1002/path.4115] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Revised: 09/13/2012] [Accepted: 09/14/2012] [Indexed: 12/20/2022]
Abstract
Fibrotic disorders are multistage progressive processes that often arise from different causes and are commonly associated with chronic inflammation. Excessive deposition of extracellular matrix is the hallmark of many fibrotic diseases. This may be due to an excess of fibroblast recruitment and activation, as well as to their differentiation in myofibroblasts. These events may be triggered by cytokines, chemokines and growth factors released by lymphocytes or macrophages. The excessive production of extracellular matrix is apparently due to alterations of metabolic pathways in activated fibroblasts. It has been suggested that a defective autophagy, an important subcellular pathway with multiple homeostatic roles, also recognized as a key component of both innate and acquired immunity, could play a role. In this review we illustrate recent insights in the field, suggesting the possible implication of the immune system in orchestrating the fibrotic response via the modulation of autophagic pathways.
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87
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Koca SS, Ozgen M, Dagli F, Tuzcu M, Ozercan IH, Sahin K, Isik A. Proteasome inhibition prevents development of experimental dermal fibrosis. Inflammation 2012; 35:810-7. [PMID: 21882074 DOI: 10.1007/s10753-011-9380-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Scleroderma is a chronic fibrotic disorder. Bortezomib, a proteasome inhibitor, is reported to attenuate experimentally induced renal and cardiac fibrosis. This study aimed to evaluate the preventive and therapeutic efficacies of bortezomib on a bleomycin (BLM)-induced scleroderma model. Dermal fibrosis was induced in Balb/c mice by subcutaneous BLM (100 μg/day) injections. Bortezomib (1.6 mg/kg twice/week) was applied intraperitoneally to BLM-injected mice during the first 3 weeks for preventive interventions and in the second 3 weeks for therapeutic interventions. IL-4 and TGF-β1 serum levels, dermal thicknesses, dermal inflammatory cell counts, and α-SMA-positive fibroblastic cell counts were determined, and type-I collagen, NF-κBp65, I-κBα, and JNK1 expressions were assessed. BLM applications increased serum IL-4 level, dermal inflammatory cell counts, α-SMA-positive cell counts, expression of type-I collagen, NF-κB, and JNK1, and dermal thickness in early stage of fibrosis, but serum IL-4 level and dermal inflammatory cell counts showed no increases in later stages. As a preventive intervention, bortezomib decreased dermal thickness, inflammatory cell infiltrations, fibroblastic activity, and expression of type-I collagen, NF-κB, and JNK1, but did not decrease fibroblastic activity and dermal thickness at later stages of fibrosis. Inflammatory status is prominent in the early stage of dermal fibrosis, but declines at later stages. In BLM-induced dermal fibrosis, bortezomib has a preventive anti-fibrotic and anti-inflammatory efficacy, but has no therapeutic anti-fibrotic efficacy in preexisting tissue fibrosis. These findings suggest that the effect of proteasome inhibition in early stages of dermal fibrosis may be related to its anti-inflammatory effects.
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Affiliation(s)
- Suleyman Serdar Koca
- Department of Rheumatology, Faculty of Medicine, Firat University, Elazig, Turkey.
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Caza TN, Talaber G, Perl A. Metabolic regulation of organelle homeostasis in lupus T cells. Clin Immunol 2012; 144:200-13. [PMID: 22836085 PMCID: PMC3423541 DOI: 10.1016/j.clim.2012.07.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 07/03/2012] [Indexed: 12/23/2022]
Abstract
Abnormal T-cell signaling and activation are characteristic features in systemic lupus erythematosus (SLE). Lupus T cells are shifted toward an over-activated state, important signaling pathways are rewired, and signaling molecules are replaced. Disturbances in metabolic and organelle homeostasis, importantly within the mitochondrial, endosomal, and autophagosomal compartments, underlie the changes in signal transduction. Mitochondrial hyperpolarization, enhanced endosomal recycling, and dysregulated autophagy are hallmarks of pathologic organelle homeostasis in SLE. This review is focused on the metabolic checkpoints of endosomal traffic that control immunological synapse formation and mitophagy and may thus serve as targets for treatment in SLE.
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Affiliation(s)
- Tiffany N Caza
- Department of Medicine, State University of New York Upstate Medical University, Syracuse, 13210, USA
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Speca S, Giusti I, Rieder F, Latella G. Cellular and molecular mechanisms of intestinal fibrosis. World J Gastroenterol 2012; 18:3635-61. [PMID: 22851857 PMCID: PMC3406417 DOI: 10.3748/wjg.v18.i28.3635] [Citation(s) in RCA: 177] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2011] [Revised: 03/26/2012] [Accepted: 04/09/2012] [Indexed: 02/06/2023] Open
Abstract
Fibrosis is a chronic and progressive process characterized by an excessive accumulation of extracellular matrix (ECM) leading to stiffening and/or scarring of the involved tissue. Intestinal fibrosis may develop in several different enteropathies, including inflammatory bowel disease. It develops through complex cell, extracellular matrix, cytokine and growth factor interactions. Distinct cell types are involved in intestinal fibrosis, such as resident mesenchymal cells (fibroblasts, myofibroblasts and smooth muscle cells) but also ECM-producing cells derived from epithelial and endothelial cells (through a process termed epithelial- and endothelial-mesenchymal transition), stellate cells, pericytes, local or bone marrow-derived stem cells. The most important soluble factors that regulate the activation of these cells include cytokines, chemokines, growth factors, components of the renin-angiotensin system, angiogenic factors, peroxisome proliferator-activated receptors, mammalian target of rapamycin, and products of oxidative stress. It soon becomes clear that although inflammation is responsible for triggering the onset of the fibrotic process, it only plays a minor role in the progression of this condition, as fibrosis may advance in a self-perpetuating fashion. Definition of the cellular and molecular mechanisms involved in intestinal fibrosis may provide the key to developing new therapeutic approaches.
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Patel AS, Lin L, Geyer A, Haspel JA, An CH, Cao J, Rosas IO, Morse D. Autophagy in idiopathic pulmonary fibrosis. PLoS One 2012; 7:e41394. [PMID: 22815997 PMCID: PMC3399849 DOI: 10.1371/journal.pone.0041394] [Citation(s) in RCA: 274] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Accepted: 06/21/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Autophagy is a basic cellular homeostatic process important to cell fate decisions under conditions of stress. Dysregulation of autophagy impacts numerous human diseases including cancer and chronic obstructive lung disease. This study investigates the role of autophagy in idiopathic pulmonary fibrosis. METHODS Human lung tissues from patients with IPF were analyzed for autophagy markers and modulating proteins using western blotting, confocal microscopy and transmission electron microscopy. To study the effects of TGF-β(1) on autophagy, human lung fibroblasts were monitored by fluorescence microscopy and western blotting. In vivo experiments were done using the bleomycin-induced fibrosis mouse model. RESULTS Lung tissues from IPF patients demonstrate evidence of decreased autophagic activity as assessed by LC3, p62 protein expression and immunofluorescence, and numbers of autophagosomes. TGF-β(1) inhibits autophagy in fibroblasts in vitro at least in part via activation of mTORC1; expression of TIGAR is also increased in response to TGF-β(1). In the bleomycin model of pulmonary fibrosis, rapamycin treatment is antifibrotic, and rapamycin also decreases expression of á-smooth muscle actin and fibronectin by fibroblasts in vitro. Inhibition of key regulators of autophagy, LC3 and beclin-1, leads to the opposite effect on fibroblast expression of á-smooth muscle actin and fibronectin. CONCLUSION Autophagy is not induced in pulmonary fibrosis despite activation of pathways known to promote autophagy. Impairment of autophagy by TGF-β(1) may represent a mechanism for the promotion of fibrogenesis in IPF.
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Affiliation(s)
- Avignat S. Patel
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ling Lin
- Department of Medicine, Pennsylvania State University, Hershey, Pennsylvainia, United States of America
| | - Alexander Geyer
- Division of Pulmonary, Critical Care, and Sleep Medicine, Mt. Sinai School of Medicine, New York, United States of America
| | - Jeffrey A. Haspel
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Chang Hyeok An
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Jiaofei Cao
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ivan O. Rosas
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- Lovelace Respiratory Research Institute, Albuquerque, New Mexico, United States of America
| | - Danielle Morse
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail: (DM)
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Spies CM, Straub RH, Buttgereit F. Energy metabolism and rheumatic diseases: from cell to organism. Arthritis Res Ther 2012; 14:216. [PMID: 22747923 PMCID: PMC3446535 DOI: 10.1186/ar3885] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
In rheumatic and other chronic inflammatory diseases, high amounts of energy for the activated immune system have to be provided and allocated by energy metabolism. In recent time many new insights have been gained into the control of the immune response through metabolic signals. Activation of immune cells as well as reduced nutrient supply and hypoxia in inflamed tissues cause stimulation of glycolysis and other cellular metabolic pathways. However, persistent cellular metabolic signals can promote ongoing chronic inflammation and loss of immune tolerance. On the organism level, the neuroendocrine immune response of the hypothalamic-pituitary adrenal axis and sympathetic nervous system, which is meant to overcome a transient inflammatory episode, can lead to metabolic disease sequelae if chronically activated. We conclude that, on cellular and organism levels, a prolonged energy appeal reaction is an important factor of chronic inflammatory disease etiology.
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Affiliation(s)
- Cornelia M Spies
- Department of Rheumatology and Clinical Immunology, Charité University Medicine Berlin, Charitéplatz 1, 10117 Berlin, Germany.
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Animal models of cutaneous and hepatic fibrosis. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 105:371-409. [PMID: 22137437 DOI: 10.1016/b978-0-12-394596-9.00011-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Fibrosis occurs as a part of normal wound healing. However, excessive or dysregulated fibrosis can lead to severe organ dysfunction and is a feature of a variety of diseases. Due to its insidious onset, fibrosis tends to go undetected in its early stages. This is in part why these diseases remain so poorly understood. Animal models have provided a means to examine these early stages and to isolate and understand the effect of perturbations in signaling pathways, chemokines, and cytokines. Here, we summarize recent progress in the understanding of the molecular pathogenesis of fibrosis, both its initiation and its maintenance phases, from animal models of fibrosis in the skin and liver. Due to these organs' properties, modeling fibrosis in them poses unique challenges. Elegant solutions have therefore been developed for modeling fibrosis in each, and now, great potential for animal models to contribute to our understanding appears scientifically imminent.
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Xu T, Xie J, Wang W, Ren H, Chen N. Impact of Rapamycin on Peritoneal Fibrosis and Transport Function. Blood Purif 2012; 34:48-57. [DOI: 10.1159/000339814] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Accepted: 05/30/2012] [Indexed: 12/13/2022]
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Goc A, Choudhary M, Byzova TV, Somanath PR. TGFβ- and bleomycin-induced extracellular matrix synthesis is mediated through Akt and mammalian target of rapamycin (mTOR). J Cell Physiol 2011; 226:3004-13. [PMID: 21302298 DOI: 10.1002/jcp.22648] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A number of pro-fibrogenic stimuli, such as growth factors, cytokines, and extracellular matrix (ECM) proteins, involve Akt and its downstream substrates in mediating their effects. We previously reported that absence of Akt1, which is the predominant isoform of the three gene Akt family in vascular cells, resulted in impaired ECM remodeling in skin and vasculature. In the current study, we investigated the importance of Akt1 in TGFβ- and bleomycin-induced synthesis and secretion of ECM proteins by fibroblasts. We observed that both TGFβ and bleomycin stimulated the synthesis of ECM proteins in a dose- and time-dependent manner. Treatment with TGFβ and bleomycin also resulted in increased phosphorylation of Akt, mammalian target of rapamycin (mTOR) and their downstream signaling partners, p70S6 Kinase, Ribosomal S6 protein and 4E-BP1, resulting in the activation of this pathway. The effects of TGFβ and bleomycin on ECM synthesis were blunted by pre-treatment with an mTOR inhibitor rapamycin. Whereas mTOR is responsible for the transcriptional regulation of a number of ECM proteins, adhesion molecules and matrix metalloproteases (MMPs), synthesis of major ECM proteins such as fibronectin and collagens (types I, II and V) by fibroblasts in response to TGFβ and bleomycin is regulated by mTOR at the translational level. These findings indicate the importance of the Akt-mTOR signaling pathway in TGF-mediated fibrogenic events in vivo.
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Affiliation(s)
- Anna Goc
- Program in Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Medical College of Georgia, Augusta, Georgia 30912-2450, USA
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Yoshizaki A, Yanaba K, Ogawa A, Asano Y, Kadono T, Sato S. Immunization with DNA topoisomerase I and Freund's complete adjuvant induces skin and lung fibrosis and autoimmunity via interleukin-6 signaling. ACTA ACUST UNITED AC 2011; 63:3575-85. [DOI: 10.1002/art.30539] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Sagiroglu T, Sezer A, Altaner S, Umit H, Yalta T, Yagci MA. The effects of sirolimus on target organs during mesenteric ischemia and reperfusion damage in an experimental rat model. Curr Ther Res Clin Exp 2011; 72:79-93. [PMID: 24648578 DOI: 10.1016/j.curtheres.2011.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/21/2011] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Mesenteric ischemia and reperfusion (I/R) syndrome (MIRS) has been considered a clinicopathologic entity associated with a variety of clinically severe conditions with decreased intestinal blood flow and has been known to induce I/R damage in various organs. Sirolimus (SRL), a macrolide antibiotic isolated from a strain of Streptomyces hygroscopicus, is a potent and nonnephrotoxic immunosuppressant. OBJECTIVE This study was designed to investigate the potential impact of sirolimus on MIRS-induced I/R damage in renal, intestinal, pulmonary, and hepatic tissues in an experimental rat model. METHODS Twenty-four male Sprague-Dawley rats, aged 6 to 8 weeks and weighing 280 (±20 g), were studied. Using computer-generated random numbers, rats were assigned to 1 of the following 3 groups: group 1 (I/R group, n = 8), group 2 (I/R + sirolimus group, n = 8), and group 3 (control group, n = 8). Sirolimus, in a 1 mg/mL (60 mL) solution, was administered intraperitoneally in a dose of 1.5 mg/kg/d to the rats assigned to group 2 starting from 3 days before the surgical procedure. In surgery, a laparotomy was performed to clamp the superior mesenteric artery and, thus, induce bowel ischemia in groups 1 and 2. After 60 minutes of ischemia, the microvascular clamp on the superior mesenteric artery was removed for 3 hours of reperfusion. Soon after experimental induction of MIRS, bowel, lung, kidney, and liver specimens from each animal were harvested for both biochemical and histopathologic analysis. RESULTS There were statistically significant differences between groups 1 and 3 with regard to degrees of intestinal (P < 0.001), hepatic (P = 0.001), renal (P < 0.001), and pulmonary (P = 0.01) I/R damage. The lung specimens from group 2 had less inflammation and perivascular edema formation compared with specimens from group 1, but no statistical significance was observed between the groups (P < 0.33). There were statistically significant differences between groups 1 and 2 with regard to degrees of intestinal, hepatic, and renal I/R damage (P = 0.001 for all). CONCLUSION The findings of the present study demonstrate the attenuating effects of sirolimus on I/R damage in the intestine and remote organs, including the liver and kidney in the setting of MIRS in an experimental rat model. As a therapeutic implication, the utility of sirolimus may be of clinical value in procedures associated with a high likelihood of I/R damage, including major abdominal operations and renal transplantation. However, whether these results apply to humans is unclear. Additional experimental and clinical studies are warranted to confirm the clinical utility of sirolimus in conditions potentially associated with I/R damage.
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Affiliation(s)
- Tamer Sagiroglu
- Department of General Surgery, Faculty of Medicine, Trakya University, Edirne, Turkey
| | - Atakan Sezer
- Department of General Surgery, Faculty of Medicine, Trakya University, Edirne, Turkey
| | - Semsi Altaner
- Department of Pathology, Faculty of Medicine, Trakya University, Edirne, Turkey
| | - Hasan Umit
- Department of Gastroenterology, Faculty of Medicine, Trakya University, Edirne, Turkey
| | - Tulin Yalta
- Department of Pathology, Faculty of Medicine, Trakya University, Edirne, Turkey
| | - Mehmet Ali Yagci
- Department of General Surgery, Faculty of Medicine, Trakya University, Edirne, Turkey
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