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Pan T, Liu F, Hao X, Wang S, Wasi M, Song JH, Lewis VO, Lin PP, Moon B, Bird JE, Panaretakis T, Lin SH, Wu D, Farach-Carson MC, Wang L, Zhang N, An Z, Zhang XHF, Satcher RL. BIGH3 mediates apoptosis and gap junction failure in osteocytes during renal cell carcinoma bone metastasis progression. Cancer Lett 2024; 596:217009. [PMID: 38849015 DOI: 10.1016/j.canlet.2024.217009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 05/26/2024] [Accepted: 05/30/2024] [Indexed: 06/09/2024]
Abstract
Renal cell carcinoma (RCC) bone metastatis progression is driven by crosstalk between tumor cells and the bone microenvironment, which includes osteoblasts, osteoclasts, and osteocytes. RCC bone metastases (RCCBM) are predominantly osteolytic and resistant to antiresorptive therapy. The molecular mechanisms underlying pathologic osteolysis and disruption of bone homeostasis remain incompletely understood. We previously reported that BIGH3/TGFBI (transforming growth factor-beta-induced protein ig-h3, shortened to BIGH3 henceforth) secreted by colonizing RCC cells drives osteolysis by inhibiting osteoblast differentiation, impairing healing of osteolytic lesions, which is reversible with osteoanabolic agents. Here, we report that BIGH3 induces osteocyte apoptosis in both human RCCBM tissue specimens and in a preclinical mouse model. We also demonstrate that BIGH3 reduces Cx43 expression, blocking gap junction (GJ) function and osteocyte network communication. BIGH3-mediated GJ inhibition is blocked by the lysosomal inhibitor hydroxychloroquine (HCQ), but not osteoanabolic agents. Our results broaden the understanding of pathologic osteolysis in RCCBM and indicate that targeting the BIGH3 mechanism could be a combinational strategy for the treatment of RCCBM-induced bone disease that overcomes the limited efficacy of antiresorptives that target osteoclasts.
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Affiliation(s)
- Tianhong Pan
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Fengshuo Liu
- Departments of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Xiaoxin Hao
- Departments of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Shubo Wang
- Department of Mechanical Engineering, University of Delaware, Newark, DE, USA
| | - Murtaza Wasi
- Department of Mechanical Engineering, University of Delaware, Newark, DE, USA
| | - Jian H Song
- Departments of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Valerae O Lewis
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Patrick P Lin
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Bryan Moon
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Justin E Bird
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Theocharis Panaretakis
- Departments of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Sue-Hwa Lin
- Departments of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; Departments of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Danielle Wu
- Department of Diagnostic and Biomedical Sciences, The University of Texas Health Science Center at Houston, School of Dentistry, Houston, TX, USA; Departments of Bioengineering, Rice University, Houston, TX, USA
| | - Mary C Farach-Carson
- Department of Diagnostic and Biomedical Sciences, The University of Texas Health Science Center at Houston, School of Dentistry, Houston, TX, USA; Departments of BioSciences, Rice University, Houston, TX, USA; Departments of Bioengineering, Rice University, Houston, TX, USA
| | - Liyun Wang
- Department of Mechanical Engineering, University of Delaware, Newark, DE, USA
| | - Ningyan Zhang
- The Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, USA
| | - Zhiqiang An
- The Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, USA
| | - Xiang H-F Zhang
- Departments of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA; Departments of Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA; Departments of Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, USA; Departments of McNair Medical Institute, Baylor College of Medicine, Houston, TX, USA
| | - Robert L Satcher
- Departments of Orthopedic Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
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Huang H, Tang Q, Li S, Qin Y, Zhu G. TGFBI: A novel therapeutic target for cancer. Int Immunopharmacol 2024; 134:112180. [PMID: 38733822 DOI: 10.1016/j.intimp.2024.112180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/26/2024] [Accepted: 04/27/2024] [Indexed: 05/13/2024]
Abstract
TGFBI, an extracellular matrix protein induced by transforming growth factor β, has been found to exhibit aberrant expression in various types of cancer. TGFBI plays a crucial role in tumor cell proliferation, angiogenesis, and apoptosis. It also facilitates invasion and metastasis in various types of cancer, including colon, head and neck squamous, renal, and prostate cancers. TGFBI, a prominent p-EMT marker, strongly correlates with lymph node metastasis. TGFBI demonstrates immunosuppressive effects within the tumor immune microenvironment. Targeted therapy directed at TGFBI shows promise as a potential strategy to combat cancer. Hence, a comprehensive review was conducted to examine the impact of TGFBI on various aspects of tumor biology, including cell proliferation, angiogenesis, invasion, metastasis, apoptosis, and the immune microenvironment. This review also delved into the underlying biochemical mechanisms to enhance our understanding of the research advancements related to TGFBI in the context of tumors.
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Affiliation(s)
- Huimei Huang
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Qinglai Tang
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Shisheng Li
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Yuexiang Qin
- Department of Otolaryngology-Head and Neck Surgery, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Gangcai Zhu
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, China.
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Zhang W, Ma L, Zhou Q, Gu T, Zhang X, Xing H. Therapeutic Targets for Diabetic Kidney Disease: Proteome-Wide Mendelian Randomization and Colocalization Analyses. Diabetes 2024; 73:618-627. [PMID: 38211557 PMCID: PMC10958583 DOI: 10.2337/db23-0564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 12/23/2023] [Indexed: 01/13/2024]
Abstract
At present, safe and effective treatment drugs are urgently needed for diabetic kidney disease (DKD). Circulating protein biomarkers with causal genetic evidence represent promising drug targets, which provides an opportunity to identify new therapeutic targets. Summary data from two protein quantitative trait loci studies are presented, one involving 4,907 plasma proteins data from 35,559 individuals and the other encompassing 4,657 plasma proteins among 7,213 European Americans. Summary statistics for DKD were obtained from a large genome-wide association study (3,345 cases and 2,372 controls) and the FinnGen study (3,676 cases and 283,456 controls). Mendelian randomization (MR) analysis was conducted to examine the potential targets for DKD. The colocalization analysis was used to detect whether the potential proteins exist in the shared causal variants. To enhance the credibility of the results, external validation was conducted. Additionally, enrichment analysis, assessment of protein druggability, and the protein-protein interaction networks were used to further enrich the research findings. The proteome-wide MR analyses identified 21 blood proteins that may causally be associated with DKD. Colocalization analysis further supported a causal relationship between 12 proteins and DKD, with external validation confirming 4 of these proteins, and TGFBI was affirmed through two separate group data sets. These results indicate that targeting these four proteins could be a promising approach for treating DKD, and warrant further clinical investigations. ARTICLE HIGHLIGHTS
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Affiliation(s)
- Wei Zhang
- Department of Nephrology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
| | - Leilei Ma
- Department of Nephrology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
| | - Qianyi Zhou
- Department of Nephrology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
| | - Tianjiao Gu
- Department of Endocrinology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
| | - Xiaotian Zhang
- Department of Nephrology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
| | - Haitao Xing
- Department of Nephrology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
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Dou F, Liu Q, Lv S, Xu Q, Wang X, Liu S, Liu G. FN1 and TGFBI are key biomarkers of macrophage immune injury in diabetic kidney disease. Medicine (Baltimore) 2023; 102:e35794. [PMID: 37960829 PMCID: PMC10637504 DOI: 10.1097/md.0000000000035794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 10/04/2023] [Indexed: 11/15/2023] Open
Abstract
The pathogenesis of diabetic kidney disease (DKD) is complex, and the existing treatment methods cannot control disease progression well. Macrophages play an important role in the development of DKD. This study aimed to search for biomarkers involved in immune injury induced by macrophages in DKD. The GSE96804 dataset was downloaded and analyzed by the CIBERSORT algorithm to understand the differential infiltration of macrophages between DKD and normal controls. Weighted gene co-expression network analysis was used to explore the correlation between gene expression modules and macrophages in renal tissue of DKD patients. Protein-protein interaction network and machine learning algorithm were used to screen the hub genes in the key modules. Subsequently, the GSE30528 dataset was used to further validate the expression of hub genes and analyze the diagnostic effect by the receiver operating characteristic curve. The clinical data were applied to explore the prognostic significance of hub genes. CIBERSORT analysis showed that macrophages increased significantly in DKD renal tissue samples. A total of ten modules were generated by weighted gene co-expression network analysis, of which the blue module was closely associated with macrophages. The blue module mainly played an important role in biological processes such as immune response and fibrosis. Fibronectin 1 (FN1) and transforming growth factor beta induced (TGFBI) were identified as hub genes of DKD patients. Receiver operating characteristic curve analysis was performed in the test cohort: FN1 and TGFBI had larger area under the curve values (0.99 and 0.88, respectively). Clinical validation showed that 2 hub genes were negatively correlated with the estimated glomerular filtration rate in DKD patients. In addition, FN1 and TGFBI showed a strong positive correlation with macrophage alternative activation. FN1 and TGFBI are promising biomarkers for the diagnosis and treatment of DKD patients, which may participate in immune response and fibrosis induced by macrophages.
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Affiliation(s)
- Fulin Dou
- Department of Nephrology, The Second Hospital of Shandong University, Jinan, China
| | - Qingzhen Liu
- Department of Nephrology, The Second Hospital of Shandong University, Jinan, China
| | - Shasha Lv
- Department of Nephrology, The Second Hospital of Shandong University, Jinan, China
| | - Qiaoying Xu
- Department of Nephrology, The Second Hospital of Shandong University, Jinan, China
| | - Xueling Wang
- Department of Nephrology, The Second Hospital of Shandong University, Jinan, China
| | - Shanshan Liu
- Department of Nephrology, The Second Hospital of Shandong University, Jinan, China
| | - Gang Liu
- Department of Nephrology, The Second Hospital of Shandong University, Jinan, China
- Nephrology Research Institute of Shandong University, The Second Hospital of Shandong University, Jinan, China
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Meng X, Wei M, Wang D, Qu X, Zhang K, Zhang N, Li X. Astragalus polysaccharides protect renal function and affect the TGF- β/Smad signaling pathway in streptozotocin-induced diabetic rats. J Int Med Res 2020; 48:300060520903612. [PMID: 32475187 PMCID: PMC7263164 DOI: 10.1177/0300060520903612] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 01/09/2020] [Indexed: 01/23/2023] Open
Abstract
OBJECTIVES The objective was to observe the effects of Astragalus polysaccharides on diabetes and on regulation of the TGF-β/Smad signaling pathway. METHODS A type 2 diabetic rat model was established with a high-fat diet in combination with low-dose streptozotocin (35 mg/kg). Astragalus polysaccharides were applied as treatment intervention and changes in blood glucose and kidney morphology and function were assessed. RESULTS Eight weeks after model establishment, kidney weight as a proportion of total weight (KW/TW) in the high-, medium-, and low-dose Astragalus polysaccharide groups was significantly lower than that in the model group, and the KW/TW value gradually decreased with increasing dose of polysaccharides in each treatment group. Fasting blood glucose in the low- and medium-dose Astragalus polysaccharide groups was numerically lower than that in the model group and fasting blood glucose in rats in the high-dose group was significantly lower than that in the model group. Levels of 24-hour urinary microalbumin, creatinine, blood urea nitrogen, collagens I, III, and IV, α-smooth muscle actin, transforming growth factor-β1, and Smad3 in Astragalus polysaccharide groups (all doses) were significantly lower than those in the model group. CONCLUSIONS Astragalus polysaccharide significantly improved blood glucose and protected kidney function in a rat diabetes model.
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Affiliation(s)
- Xue Meng
- Department of Nephrology, Affiliated Hospital of Jining Medical University, Jining, Shandong, China
| | - Mingmin Wei
- Department of Nephrology, Affiliated Hospital of Jining Medical University, Jining, Shandong, China
| | - Dong Wang
- Department of Nephrology, Affiliated Hospital of Jining Medical University, Jining, Shandong, China
| | - Xiaohan Qu
- Department of Nephrology, Affiliated Hospital of Jining Medical University, Jining, Shandong, China
| | - Kun Zhang
- Department of Nephrology, Affiliated Hospital of Jining Medical University, Jining, Shandong, China
| | - Nan Zhang
- Department of Nephrology, Affiliated Hospital of Jining Medical University, Jining, Shandong, China
| | - Xinjian Li
- Department of Nephrology, Affiliated Hospital of Jining Medical University, Jining, Shandong, China
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Steuber M, Schönherr H. Guided assembly, nanostructuring and functionalization with brushes of microscale polymer cubes for tailored 3-D cell microenvironments. Eur Polym J 2019. [DOI: 10.1016/j.eurpolymj.2019.01.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Han J, Zhang M, Lin HY, Huang FY, Lin YY, Tan GH, Zheng ZY. Impaired Autophagic Degradation of Transforming Growth Factor-β-Induced Protein by Macrophages in Lattice Corneal Dystrophy. Invest Ophthalmol Vis Sci 2019; 60:978-989. [PMID: 30884524 DOI: 10.1167/iovs.18-25838] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Lattice corneal dystrophy (LCD) is related to the denaturation of transforming growth factor-β-induced protein (TGFBIp). Autophagic degradation of the denatured proteins by macrophages is one pathway to remove the denatured proteins. Thus, we investigated the role of autophagy in the degradation of mutant (MU) TGFBIp in macrophages. Methods Corneas from participants were observed by slit-lamp photography and subjected to histopathologic and genetic analysis. Wild-type (WT) and MU TGFBIp were recombined and expressed. Macrophages from MU participants were isolated and cocultured with the recombinant TGFBIp. Colocalization of the two molecules was observed by immunofluorescent microscopy. Enzyme-linked immunosorbent assay, Western blotting, and flow cytometry were used to detect changes in molecule expression related to the phenotype and autophagy process. Results Fourteen members from a family of 25 were identified as LCD sufferers. Significant TGFBIp aggregates and macrophage infiltration were found only in the corneas of LCD sufferers. Marker accumulation of TGFBIp was found in macrophages exposed to MU TGFBIp even at 5 hours after MU TGFBIp was withdrawn. High expressions of CD68 and CD36 were found in macrophages exposed to WT TGFBIp, but not to MU TGFBIp. Impaired autophagic flux due to defective autophagosome fusion to lysosomes was found in macrophages exposed to MU TGFBIp. Blockage of the autophagic process suppressed the expression of CD68 and CD36 in macrophages exposed to WT TGFBIp to levels similar to those found in macrophages exposed to MU TGFBIp. Conclusions Our results suggested that reversion of the defective autophagic process in macrophages may be a therapeutic strategy for patients with LCD.
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Affiliation(s)
- Ji Han
- Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou, China.,Department of Ophthalmology, The First Affiliated Hospital of Hainan Medical College, Haikou, China
| | - Ming Zhang
- Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou, China
| | - Hai-Yan Lin
- Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou, China
| | - Feng-Ying Huang
- Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou, China
| | - Ying-Ying Lin
- Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou, China
| | - Guang-Hong Tan
- Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou, China
| | - Zhen-You Zheng
- Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou, China.,Department of Ophthalmology, The First Affiliated Hospital of Hainan Medical College, Haikou, China
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Mukhi D, Nishad R, Menon RK, Pasupulati AK. Novel Actions of Growth Hormone in Podocytes: Implications for Diabetic Nephropathy. Front Med (Lausanne) 2017; 4:102. [PMID: 28748185 PMCID: PMC5506074 DOI: 10.3389/fmed.2017.00102] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Accepted: 06/26/2017] [Indexed: 02/05/2023] Open
Abstract
The kidney regulates water, electrolyte, and acid-base balance and thus maintains body homeostasis. The kidney’s potential to ensure ultrafiltered and almost protein-free urine is compromised in various metabolic and hormonal disorders such as diabetes mellitus (DM). Diabetic nephropathy (DN) accounts for ~20–40% of mortality in DM. Proteinuria, a hallmark of renal glomerular diseases, indicates injury to the glomerular filtration barrier (GFB). The GFB is composed of glomerular endothelium, basement membrane, and podocytes. Podocytes are terminally differentiated epithelial cells with limited ability to replicate. Podocyte shape and number are both critical for the integrity and function of the GFB. Podocytes are vulnerable to various noxious stimuli prevalent in a diabetic milieu that could provoke podocytes to undergo changes to their unique architecture and function. Effacement of podocyte foot process is a typical morphological alteration associated with proteinuria. The dedifferentiation of podocytes from epithelial-to-mesenchymal phenotype and consequential loss results in proteinuria. Poorly controlled type 1 DM is associated with elevated levels of circulating growth hormone (GH), which is implicated in the pathophysiology of various diabetic complications including DN. Recent studies demonstrate that functional GH receptors are expressed in podocytes and that GH may exert detrimental effects on the podocyte. In this review, we summarize recent advances that shed light on actions of GH on the podocyte that could play a role in the pathogenesis of DN.
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Affiliation(s)
- Dhanunjay Mukhi
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Rajkishor Nishad
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Ram K Menon
- Department of Pediatric Endocrinology and Physiology, University of Michigan, Ann Arbor, MI, United States
| | - Anil Kumar Pasupulati
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
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TGFβ induces BIGH3 expression and human retinal pericyte apoptosis: a novel pathway of diabetic retinopathy. Eye (Lond) 2016; 30:1639-1647. [PMID: 27564721 DOI: 10.1038/eye.2016.179] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 06/14/2016] [Indexed: 02/05/2023] Open
Abstract
PurposeOne of the earliest hallmarks of diabetic retinopathy is the loss of retinal pericytes. However, the mechanisms that promote pericyte dropout are unknown. In the present study, we propose a novel pathway in which pericyte apoptosis is mediated by macrophages, TGFβ and pro-apoptotic BIGH3 (TGFβ-induced Gene Human Clone 3) protein.Patients and methodsTo elucidate this pathway, we assayed human retinal pericyte (HRP) apoptosis by TUNEL assay, BIGH3 mRNA expression by qPCR, and BIGH3 protein expression by western blot analysis. HRP were treated with BIGH3 protein, TGFβ1 and TGFβ2 and inhibition assays were carried out by blocking with antibodies against BIGH3. The distribution of BIGH3 and CD68+ macrophages were compared in a post-mortem donor eye with 7-year history of Type II diabetes and histopathogically confirmed non-proliferative diabetic retinopathy (NPDR).ResultsTGFβ induced a significant increase in BIGH3 mRNA and protein expression, and HRP apoptosis. BIGH3 treatment showed HRP undergo apoptosis in a dose-dependent manner. At 5 μg/ml, BIGH3 induced 3.5-times more apoptosis in HRP than in retinal endothelial cells. TGFβ induced apoptosis was inhibited by blocking with antibodies against BIGH3. In an example of NPDR, BIGH3 accumulated within the walls of the inner retina arterioles. Macrophage infiltrates were frequently associated with these vessels and the inner nuclear layer.ConclusionTogether with our previously published results on macrophage-induced retinal endothelial cell apoptosis, the present study supports a novel inflammatory pathway mediated by macrophages and the BIGH3 protein leading to HRP apoptosis. As shown in human post-mortem globes, these observations are clinically relevant, suggesting a new mechanism underlying pericyte dropout during NPDR.
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