1
|
Yuan J, Zhao Q, Li J, Wen Y, Wu R, Zhao S, Lang YF, Yan QG, Huang X, Du S, Cao SJ. CXCL8 Knockout: A Key to Resisting Pasteurella multocida Toxin-Induced Cytotoxicity. Int J Mol Sci 2024; 25:5330. [PMID: 38791369 PMCID: PMC11121343 DOI: 10.3390/ijms25105330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 05/05/2024] [Accepted: 05/12/2024] [Indexed: 05/26/2024] Open
Abstract
Pasteurella multocida, a zoonotic pathogen that produces a 146-kDa modular toxin (PMT), causes progressive atrophic rhinitis with severe turbinate bone degradation in pigs. However, its mechanism of cytotoxicity remains unclear. In this study, we expressed PMT, purified it in a prokaryotic expression system, and found that it killed PK15 cells. The host factor CXCL8 was significantly upregulated among the differentially expressed genes in a transcriptome sequencing analysis and qPCR verification. We constructed a CXCL8-knockout cell line with a CRISPR/Cas9 system and found that CXCL8 knockout significantly increased resistance to PMT-induced cell apoptosis. CXCL8 knockout impaired the cleavage efficiency of apoptosis-related proteins, including Caspase3, Caspase8, and PARP1, as demonstrated with Western blot. In conclusion, these findings establish that CXCL8 facilitates PMT-induced PK15 cell death, which involves apoptotic pathways; this observation documents that CXCL8 plays a key role in PMT-induced PK15 cell death.
Collapse
Affiliation(s)
- Jianlin Yuan
- Research Center for Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (J.Y.); (Q.Z.); (J.L.); (Y.W.); (R.W.); (S.Z.); (Y.-F.L.); (Q.-G.Y.); (X.H.)
| | - Qin Zhao
- Research Center for Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (J.Y.); (Q.Z.); (J.L.); (Y.W.); (R.W.); (S.Z.); (Y.-F.L.); (Q.-G.Y.); (X.H.)
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
- National Demonstration Center for Experimental Animal Education, Sichuan Agricultural University, Chengdu 611130, China
| | - Jinfeng Li
- Research Center for Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (J.Y.); (Q.Z.); (J.L.); (Y.W.); (R.W.); (S.Z.); (Y.-F.L.); (Q.-G.Y.); (X.H.)
| | - Yiping Wen
- Research Center for Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (J.Y.); (Q.Z.); (J.L.); (Y.W.); (R.W.); (S.Z.); (Y.-F.L.); (Q.-G.Y.); (X.H.)
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
- National Demonstration Center for Experimental Animal Education, Sichuan Agricultural University, Chengdu 611130, China
| | - Rui Wu
- Research Center for Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (J.Y.); (Q.Z.); (J.L.); (Y.W.); (R.W.); (S.Z.); (Y.-F.L.); (Q.-G.Y.); (X.H.)
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
- National Demonstration Center for Experimental Animal Education, Sichuan Agricultural University, Chengdu 611130, China
| | - Shan Zhao
- Research Center for Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (J.Y.); (Q.Z.); (J.L.); (Y.W.); (R.W.); (S.Z.); (Y.-F.L.); (Q.-G.Y.); (X.H.)
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
- National Demonstration Center for Experimental Animal Education, Sichuan Agricultural University, Chengdu 611130, China
| | - Yi-Fei Lang
- Research Center for Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (J.Y.); (Q.Z.); (J.L.); (Y.W.); (R.W.); (S.Z.); (Y.-F.L.); (Q.-G.Y.); (X.H.)
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
- National Demonstration Center for Experimental Animal Education, Sichuan Agricultural University, Chengdu 611130, China
| | - Qi-Gui Yan
- Research Center for Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (J.Y.); (Q.Z.); (J.L.); (Y.W.); (R.W.); (S.Z.); (Y.-F.L.); (Q.-G.Y.); (X.H.)
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
- National Demonstration Center for Experimental Animal Education, Sichuan Agricultural University, Chengdu 611130, China
| | - Xiaobo Huang
- Research Center for Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (J.Y.); (Q.Z.); (J.L.); (Y.W.); (R.W.); (S.Z.); (Y.-F.L.); (Q.-G.Y.); (X.H.)
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
- National Demonstration Center for Experimental Animal Education, Sichuan Agricultural University, Chengdu 611130, China
| | - Senyan Du
- Research Center for Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (J.Y.); (Q.Z.); (J.L.); (Y.W.); (R.W.); (S.Z.); (Y.-F.L.); (Q.-G.Y.); (X.H.)
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
- National Demonstration Center for Experimental Animal Education, Sichuan Agricultural University, Chengdu 611130, China
| | - San-Jie Cao
- Research Center for Swine Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China; (J.Y.); (Q.Z.); (J.L.); (Y.W.); (R.W.); (S.Z.); (Y.-F.L.); (Q.-G.Y.); (X.H.)
- Sichuan Science-Observation Experimental Station of Veterinary Drugs and Veterinary Diagnostic Technique, Ministry of Agriculture and Rural Affairs, Chengdu 611130, China
- National Demonstration Center for Experimental Animal Education, Sichuan Agricultural University, Chengdu 611130, China
| |
Collapse
|
2
|
Chakraborty S, Handrick B, Yu D, Bode KA, Hafner A, Schenz J, Schaack D, Uhle F, Tachibana T, Kamitani S, Vogl T, Kubatzky KF. Gα q modulates the energy metabolism of osteoclasts. Front Cell Infect Microbiol 2023; 12:1016299. [PMID: 36699722 PMCID: PMC9869164 DOI: 10.3389/fcimb.2022.1016299] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 12/09/2022] [Indexed: 01/12/2023] Open
Abstract
Introduction The bacterial protein toxin Pasteurella multocida toxin (PMT) mediates RANKL-independent osteoclast differentiation. Although these osteoclasts are smaller, their resorptive activity is high which helps in efficient destruction of nasal turbinate bones of pigs. Methods The proteome of bone marrow-derived macrophages differentiated into osteoclasts with either RANKL or PMT was analysed. The results were verified by characterizing the metabolic activity using Seahorse analysis, a protein translation assay, immunoblots, real-time PCR as well as flow cytometry-based monitoring of mitochondrial activity and ROS production. A Gαq overexpression system using ER-Hoxb8 cells was used to identify Gαq-mediated metabolic effects on osteoclast differentiation and function. Results PMT induces the upregulation of metabolic pathways, which included strong glycolytic activity, increased expression of GLUT1 and upregulation of the mTOR pathway. As OxPhos components were expressed more efficiently, cells also displayed increased mitochondrial respiration. The heterotrimeric G protein Gαq plays a central role in this hypermetabolic cell activation as it triggers mitochondrial relocalisation of pSerSTAT3 and an increase in OPA1 expression. This seems to be caused by a direct interaction between STAT3 and OPA1 resulting in enhanced mitochondrial respiration. Overexpression of Gαq mimicked the hypermetabolic phenotype observed for PMT-induced osteoclasts and resulted in higher glycolytic and mitochondrial activity as well as increased bone resorptive activity. In addition, rheumatoid arthritis (RA) patients showed an increase in GNAQ expression, especially in the synovial fluid. Discussion Our study suggests that Gαq plays a key role in PMT-induced osteoclastogenesis. Enhanced expression of GNAQ at the site of inflammation in RA patients indicates its pathophysiological relevance in the context of inflammatory bone disorders.
Collapse
Affiliation(s)
- Sushmita Chakraborty
- Department of Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg University, Heidelberg, Germany
- Department of Transplant Immunology and Immunogenetics, All India Institute of Medical Sciences, New Delhi, India
| | - Bianca Handrick
- Department of Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg University, Heidelberg, Germany
| | - Dayoung Yu
- Department of Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg University, Heidelberg, Germany
| | - Konrad A. Bode
- Department of Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg University, Heidelberg, Germany
| | - Anna Hafner
- Department of Anesthesiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Judith Schenz
- Department of Anesthesiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Dominik Schaack
- Department of Anesthesiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Florian Uhle
- Department of Anesthesiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Taro Tachibana
- Department of Chemistry and Bioengineering, Graduate School of Engineering, Osaka Metropolitan University, Osaka, Japan
| | - Shigeki Kamitani
- Department of Nutrition, Graduate School of Human Life and Ecology, Osaka Metropolitan University, Osaka, Japan
| | - Thomas Vogl
- Institute of Immunology, University Hospital Münster, Münster, Germany
| | - Katharina F. Kubatzky
- Department of Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg University, Heidelberg, Germany
| |
Collapse
|
3
|
Kubatzky KF. Pasteurella multocida toxin - lessons learned from a mitogenic toxin. Front Immunol 2022; 13:1058905. [PMID: 36591313 PMCID: PMC9800868 DOI: 10.3389/fimmu.2022.1058905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
The gram-negative, zoonotic bacterium Pasteurella multocida was discovered in 1880 and found to be the causative pathogen of fowl cholera. Pasteurella-related diseases can be found in domestic and wild life animals such as buffalo, sheep, goat, deer and antelope, cats, dogs and tigers and cause hemorrhagic septicemia in cattle, rhinitis or pneumonia in rabbits or fowl cholera in poultry and birds. Pasteurella multocida does not play a major role in the immune-competent human host, but can be found after animal bites or in people with close contact to animals. Toxigenic strains are most commonly found in pigs and express a phage-encoded 146 kDa protein, the Pasteurella multocida toxin (PMT). Toxin-expressing strains cause atrophic rhinitis where nasal turbinate bones are destroyed through the inhibition of bone building osteoblasts and the activation of bone resorbing osteoclasts. After its uptake through receptor-mediated endocytosis, PMT specifically targets the alpha subunit of several heterotrimeric G proteins and constitutively activates them through deamidation of a glutamine residue to glutamate in the alpha subunit. This results in cytoskeletal rearrangement, proliferation, differentiation and survival of cells. Because of the toxin's mitogenic effects, it was suggested that it might have carcinogenic properties, however, no link between Pasteurella infections and cell transformation could be established, neither in tissue culture models nor through epidemiological data. In the recent years it was shown that the toxin not only affects bone, but also the heart as well as basically all cells of innate and adaptive immunity. During the last decade the focus of research shifted from signal transduction processes to understanding how the bacteria might benefit from a bone-destroying toxin. The primary function of PMT seems to be the modulation of immune cell activation which at the same time creates an environment permissive for osteoclast formation. While the disease is restricted to pigs, the implications of the findings from PMT research can be used to explore human diseases and have a high translational potential. In this review our current knowledge will be summarized and it will be discussed what can be learned from using PMT as a tool to understand human pathologies.
Collapse
Affiliation(s)
- Katharina F. Kubatzky
- Department of Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg University, Heidelberg, Germany
| |
Collapse
|
4
|
Cai H, Wang Z, Tang W, Ke X, Zhao E. Recent advances of the mammalian target of rapamycin signaling in mesenchymal stem cells. Front Genet 2022; 13:970699. [PMID: 36110206 PMCID: PMC9468880 DOI: 10.3389/fgene.2022.970699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 08/11/2022] [Indexed: 11/22/2022] Open
Abstract
Mammalian target of rapamycin (mTOR) is a serine/threonine kinase involved in a variety of cellular functions, such as cell proliferation, metabolism, autophagy, survival and cytoskeletal organization. Furthermore, mTOR is made up of three multisubunit complexes, mTOR complex 1, mTOR complex 2, and putative mTOR complex 3. In recent years, increasing evidence has suggested that mTOR plays important roles in the differentiation and immune responses of mesenchymal stem cells (MSCs). In addition, mTOR is a vital regulator of pivotal cellular and physiological functions, such as cell metabolism, survival and ageing, where it has emerged as a novel therapeutic target for ageing-related diseases. Therefore, the mTOR signaling may develop a large impact on the treatment of ageing-related diseases with MSCs. In this review, we discuss prospects for future research in this field.
Collapse
Affiliation(s)
- Huarui Cai
- State Key Laboratory of Silkworm Genome Biology, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China
- Cancer Center, Medical Research Institute, Southwest University, Chongqing, China
| | - Zhongze Wang
- State Key Laboratory of Silkworm Genome Biology, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China
- Cancer Center, Medical Research Institute, Southwest University, Chongqing, China
| | - Wenhan Tang
- State Key Laboratory of Silkworm Genome Biology, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China
| | - Xiaoxue Ke
- State Key Laboratory of Silkworm Genome Biology, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China
- Cancer Center, Medical Research Institute, Southwest University, Chongqing, China
- *Correspondence: Xiaoxue Ke, ; Erhu Zhao,
| | - Erhu Zhao
- State Key Laboratory of Silkworm Genome Biology, College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China
- Cancer Center, Medical Research Institute, Southwest University, Chongqing, China
- *Correspondence: Xiaoxue Ke, ; Erhu Zhao,
| |
Collapse
|
5
|
Abdulrahman RF, Davies RL. Diversity and characterization of temperate bacteriophages induced in Pasteurella multocida from different host species. BMC Microbiol 2021; 21:97. [PMID: 33784980 PMCID: PMC8008546 DOI: 10.1186/s12866-021-02155-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 02/25/2021] [Indexed: 12/31/2022] Open
Abstract
Background Bacteriophages play important roles in the evolution of bacteria and in the emergence of new pathogenic strains by mediating the horizontal transfer of virulence genes. Pasteurella multocida is responsible for different disease syndromes in a wide range of domesticated animal species. However, very little is known about the influence of bacteriophages on disease pathogenesis in this species. Results Temperate bacteriophage diversity was assessed in 47 P. multocida isolates of avian (9), bovine (8), ovine (10) and porcine (20) origin. Induction of phage particles with mitomycin C identified a diverse range of morphological types representing both Siphoviridae and Myoviridae family-types in 29 isolates. Phage of both morphological types were identified in three isolates indicating that a single bacterial host may harbour multiple prophages. DNA was isolated from bacteriophages recovered from 18 P. multocida isolates and its characterization by restriction endonuclease (RE) analysis identified 10 different RE types. Phage of identical RE types were identified in certain closely-related strains but phage having different RE types were present in other closely-related isolates suggesting possible recent acquisition. The host range of the induced phage particles was explored using plaque assay but only 11 (38%) phage lysates produced signs of infection in a panel of indicator strains comprising all 47 isolates. Notably, the majority (9/11) of phage lysates which caused infection originated from two groups of phylogenetically unrelated ovine and porcine strains that uniquely possessed the toxA gene. Conclusions Pasteurella multocida possesses a wide range of Siphoviridae- and Myoviridae-type bacteriophages which likely play key roles in the evolution and virulence of this pathogen. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-021-02155-9.
Collapse
Affiliation(s)
- Rezheen F Abdulrahman
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, 120 University Place, Glasgow, G12 8TA, UK.,Pathology and Microbiology Department, Collage of Veterinary Medicine, University of Duhok, Kurdistan Region, Iraq
| | - Robert L Davies
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Sir Graeme Davies Building, University of Glasgow, 120 University Place, Glasgow, G12 8TA, UK.
| |
Collapse
|
6
|
Liu Z, Liu H, Li Y, Wang Y, Xing R, Mi F, Xiang C, Fu R. Adiponectin inhibits the differentiation and maturation of osteoclasts via the mTOR pathway in multiple myeloma. Int J Mol Med 2020; 45:1112-1120. [PMID: 31985020 PMCID: PMC7053860 DOI: 10.3892/ijmm.2020.4475] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Accepted: 12/10/2019] [Indexed: 01/05/2023] Open
Abstract
The present study sought to investigate the correlation between adipose cytokines (visfatin, leptin and adiponectin) and markers of multiple myeloma bone disease, and to determine the effects and mechanism of action of adiponectin on the differentiation and maturation of osteoclasts in multiple myeloma (MM). The levels of visfatin, leptin and adiponectin were measured. Their association with the indices of myeloma tumor load and bone disease were analyzed. Reverse transcription-quantitative PCR was used to detect the expression of receptor activator of nuclear factor-κB ligand (RANKL), osteoclast associated Ig-like receptor (OSCAR), tartrate-resistant acid phosphatase (TRAP) and Cathepsin K genes. Flow cytometry was used to detect the expression of adiponectin receptor 1 (AdipoR1) and the phosphorylation of the mechanistic target of rapamycin kinase (mTOR) pathway-associated proteins mTOR and eukaryotic translation initiation factor 4E-binding protein (4EBP1). There were no significant correlations among leptin, visfatin and the indexes of myeloma tumor load and bone disease. Serum adiponectin levels were significantly lower in patients with newly diagnosed multiple myeloma compared with healthy volunteers (12.37±3.13 vs. 13.80±0.95; P<0.05). The number of mature osteoclasts in the adiponectin group was lower compared with in the control group. Adiponectin also inhibited the mRNA expression of the osteoclast-associated factors RANKL, OSCAR, TRAP and Cathepsin K. Comparison between the non-adiponectin group and the adiponectin group revealed that adiponectin increased the expression of AdipoR1 on the surface of osteoclast precursor cells (26.21±4.27% vs. 29.86±6.23%; P<0.05) and reduced the expression of phosphorylated (p-)mTOR (7.89±1.00% vs. 5.91±1.26%; P<0.05) and p-4EBP1 (26.78±5.00% vs. 22.49±4.24%; P<0.05). The p-mTOR and p-4EBP1 levels in the adiponectin + MHY1485 (an mTOR signaling pathway-specific agonist) group were significantly higher compared with those in the adiponectin group. It was revealed that adiponectin may inhibit osteoclast differentiation and maturation via the mTOR pathway. In conclusion, adiponectin inhibits the differentiation and maturation of osteoclasts by increasing the expression of AdipoR1 and reducing the phosphorylation levels of mTOR and 4EBP1 in patients with MM.
Collapse
Affiliation(s)
- Zhaoyun Liu
- Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Hui Liu
- Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Yanqi Li
- Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Yangyang Wang
- Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Rui Xing
- Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Fu Mi
- Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Chenhuan Xiang
- Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| | - Rong Fu
- Department of Hematology, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China
| |
Collapse
|
7
|
Shen G, Ren H, Qiu T, Zhang Z, Zhao W, Yu X, Huang J, Tang J, Liang D, Yao Z, Yang Z, Jiang X. Mammalian target of rapamycin as a therapeutic target in osteoporosis. J Cell Physiol 2017; 233:3929-3944. [PMID: 28834576 DOI: 10.1002/jcp.26161] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 08/21/2017] [Indexed: 12/19/2022]
Abstract
The mechanistic target of rapamycin (mTOR) plays a key role in sensing and integrating large amounts of environmental cues to regulate organismal growth, homeostasis, and many major cellular processes. Recently, mounting evidences highlight its roles in regulating bone homeostasis, which sheds light on the pathogenesis of osteoporosis. The activation/inhibition of mTOR signaling is reported to positively/negatively regulate bone marrow mesenchymal stem cells (BMSCs)/osteoblasts-mediated bone formation, adipogenic differentiation, osteocytes homeostasis, and osteoclasts-mediated bone resorption, which result in the changes of bone homeostasis, thereby resulting in or protect against osteoporosis. Given the likely importance of mTOR signaling in the pathogenesis of osteoporosis, here we discuss the detailed mechanisms in mTOR machinery and its association with osteoporosis therapy.
Collapse
Affiliation(s)
- Gengyang Shen
- Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Hui Ren
- Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Ting Qiu
- Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zhida Zhang
- Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Wenhua Zhao
- Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xiang Yu
- Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jinjing Huang
- Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jingjing Tang
- Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - De Liang
- Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zhensong Yao
- Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zhidong Yang
- Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xiaobing Jiang
- Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.,Laboratory Affiliated to National Key Discipline of Orthopaedic and Traumatology of Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, China
| |
Collapse
|
8
|
Influence of Pasteurella multocida Toxin on the differentiation of dendritic cells into osteoclasts. Immunobiology 2017; 223:142-150. [PMID: 29030011 DOI: 10.1016/j.imbio.2017.09.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/07/2017] [Indexed: 01/25/2023]
Abstract
Dendritic cells (DC) are antigen-presenting cells that connect the innate and adaptive immune system to ensure an efficient immune response during the course of an infection. Recently, DC came into the spotlight as a potential source of osteoclast progenitors, especially under (auto)inflammatory conditions. The virulence factor Pasteurella multocida Toxin (PMT) causes atrophic rhinitis in pigs, a disease characterised by a severe reduction of nasal bone. Our group and others have shown the potential of PMT in mediating differentiation of monocytes/macrophages into bone-resorbing osteoclasts. However, whether DC are target cells for PMT-induced osteoclast differentiation, is currently unknown. Using different murine DC model systems, we investigated the ability of PMT to induce osteoclast formation in DC. Similar to our previous observations in macrophages, PMT was endocytosed by DC and triggered intracellular deamidation of residue Q209 of the Gq alpha subunit. Still, PMT failed to induce prolonged secretion of osteoclastogenic cytokines and osteoclast formation; instead PMT-treated DC secreted interleukin-12 (IL-12), an inhibitor of osteoclastogenesis. In this study, we show that in comparison to bone marrow-derived macrophages, PMT induces maturation of DC through increased expression of the activation markers CD80 and CD86. As maturation of DC prevents their transdifferentiation into osteoclasts, we hypothesize that PMT, a potent osteoclastogenic toxin, fails to trigger osteoclastogenesis in DC due to its effect on DC maturation and IL-12 production.
Collapse
|
9
|
Chakraborty S, Kloos B, Harre U, Schett G, Kubatzky KF. Pasteurella multocida Toxin Triggers RANKL-Independent Osteoclastogenesis. Front Immunol 2017; 8:185. [PMID: 28289415 PMCID: PMC5327351 DOI: 10.3389/fimmu.2017.00185] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 02/09/2017] [Indexed: 01/15/2023] Open
Abstract
Bone remodeling is a continuous process to retain the structural integrity and function of the skeleton. A tight coupling is maintained between osteoclast-mediated resorption of old or damaged bones and osteoblast-mediated formation of new bones for bone homeostasis. While osteoblasts differentiate from mesenchymal stem cells, osteoclasts are hematopoietic in origin and derived from myeloid precursor cells. Osteoclast differentiation is driven by two cytokines, cytokine receptor activator of NF-κB ligand (RANKL), and macrophage colony-stimulating factor. Imbalances in the activity of osteoblasts and osteoclasts result in the development of bone disorders. Bacterially caused porcine atrophic rhinitis is characterized by a loss of nasal ventral conche bones and a distortion of the snout. While Bordetella bronchiseptica strains cause mild and reversible symptoms, infection of pigs with toxigenic Pasteurella multocida strains causes a severe and irreversible decay. The responsible virulence factor Pasteurella multocida toxin (PMT) contains a deamidase activity in its catalytical domain that constitutively activates specific heterotrimeric G proteins to induce downstream signaling cascades. While osteoblasts are inhibited by the toxin, osteoclasts are activated, thus skewing bone remodeling toward excessive bone degradation. Still, the mechanism by which PMT interferes with bone homeostasis, and the reason for this unusual target tissue is not yet well understood. Here, we show that PMT has the potential to differentiate bone marrow-derived macrophages into functional osteoclasts. This toxin-mediated differentiation process is independent of RANKL, a cytokine believed to be indispensable for triggering osteoclastogenesis, as addition of osteoprotegerin to PMT-treated macrophages does not show any effect on PMT-induced osteoclast formation. Although RANKL is not a prerequisite, toxin-primed macrophages show enhanced responsiveness to low concentrations of RANKL, suggesting that the PMT-generated microenvironment offers conditions where low concentrations of RANKL lead to an increase in the number of osteoclasts resulting in increased resorption. PMT-mediated release of the osteoclastogenic cytokines such as IL-6 and TNF-α, but not IL-1, supports the differentiation process. Although the production of cytokines and the subsequent activation of signaling cascades are necessary for PMT-mediated differentiation into osteoclasts, they are not sufficient and PMT-induced activation of G protein signaling is essential for efficient osteoclastogenesis.
Collapse
Affiliation(s)
- Sushmita Chakraborty
- Zentrum für Infektiologie, Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Heidelberg , Heidelberg , Germany
| | - Bianca Kloos
- Zentrum für Infektiologie, Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Heidelberg , Heidelberg , Germany
| | - Ulrike Harre
- Department of Internal Medicine 3, Institute of Clinical Immunology, University of Erlangen-Nuremberg , Erlangen , Germany
| | - Georg Schett
- Department of Internal Medicine 3, Institute of Clinical Immunology, University of Erlangen-Nuremberg , Erlangen , Germany
| | - Katharina F Kubatzky
- Zentrum für Infektiologie, Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Heidelberg , Heidelberg , Germany
| |
Collapse
|
10
|
Wu CL, Chen CH, Hwang CS, Chen SD, Hwang WC, Yang DI. Roles of p62 in BDNF-dependent autophagy suppression and neuroprotection against mitochondrial dysfunction in rat cortical neurons. J Neurochem 2017; 140:845-861. [PMID: 28027414 DOI: 10.1111/jnc.13937] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 11/28/2016] [Accepted: 12/14/2016] [Indexed: 12/19/2022]
Abstract
Previously, we have reported that pre-conditioning of primary rat cortical neurons with brain-derived neurotrophic factor (BDNF) may exert neuroprotective effects against 3-nitropropionic acid (3-NP), a mitochondrial complex II inhibitor. However, the underlying mechanisms, especially potential involvements of autophagy, remain elusive. In this work, we tested the hypothesis that BDNF may suppress 3-NP-induced autophagy to exert its neuroprotective effects by inducing the expression of p62/sequestosome-1 in primary cortical neurons. We found that 3-NP increased total level of microtubule-associated protein 1A/1B-light chain (LC)-3 as well as the LC3-II/LC3-I ratio, an index of autophagy, in primary cortical neurons. BDNF decreased LC3-II/LC3-I ratio and time-dependently induced expression of p62. Knockdown of p62 by siRNA restored LC3-II/LC3-I ratio and increased total LC3 levels associated with BDNF exposure; p62 knockdown also abolished BDNF-dependent neuroprotection against 3-NP. Upstream of p62, we found that BDNF triggered phosphorylation of mammalian target of rapamycin (mTOR) and its downstream mediator p70S6K; importantly, the mTOR inhibitor rapamycin reduced both BDNF-dependent p62 induction as well as 3-NP resistance. BDNF is known to induce c-Jun in cortical neurons. We found that c-Jun knockdown in part attenuated BDNF-mediated p62 induction, whereas p62 knockdown had no significant effects on c-Jun expression. In addition to suppressing p62 induction, rapamycin also partially suppressed BDNF-induced c-Jun expression, but c-Jun knockdown failed to affect mTOR activation. Together, our results suggested that BDNF inhibits 3-NP-induced autophagy via, at least in part, mTOR/c-Jun-dependent induction of p62 expression, together contributing to neuroprotection against mitochondrial inhibition.
Collapse
Affiliation(s)
- Chia-Lin Wu
- Program in Molecular Medicine, National Yang-Ming University and Academia Sinica, Taipei, Taiwan.,Institute of Brain Science and Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Chien-Hui Chen
- Institute of Brain Science and Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Chi-Shin Hwang
- Department of Neurology, Taipei City Hospital, Taipei, Taiwan.,Department of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Shang-Der Chen
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.,Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Wei-Chao Hwang
- Department of Neurology, Taipei City Hospital, Taipei, Taiwan
| | - Ding-I Yang
- Institute of Brain Science and Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| |
Collapse
|
11
|
Shen G, Ren H, Qiu T, Liang D, Xie B, Zhang Z, Yao Z, Yang Z, Jiang X. Implications of the Interaction Between miRNAs and Autophagy in Osteoporosis. Calcif Tissue Int 2016; 99:1-12. [PMID: 26922423 DOI: 10.1007/s00223-016-0122-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 02/15/2016] [Indexed: 01/08/2023]
Abstract
Imbalances between bone formation and resorption are the primary cause of osteoporosis. However, currently, a detailed molecular mechanism of osteoporosis is not available. Autophagy is the conserved process characterized by degrading and recycling aggregated proteins, intracellular pathogens, and damaged organelles. MicroRNAs (miRNAs) are novel regulatory factors that play important roles in numerous cellular processes, including autophagy, through the posttranscriptional regulation of gene expression. Conversely, autophagy plays a role in the regulation of miRNA homeostasis. Recent advances have revealed that both autophagy and miRNAs are involved in the maintenance of bone homoeostasis, whereas the role of the interaction of miRNAs with autophagy in osteoporosis remains unclear. In this paper, we review previous reports on autophagy, miRNAs, and their interaction in osteoporosis.
Collapse
Affiliation(s)
- Gengyang Shen
- Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Hui Ren
- Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Ting Qiu
- Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - De Liang
- Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Bo Xie
- The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Zhida Zhang
- Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Zhensong Yao
- Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Zhidong Yang
- Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Xiaobing Jiang
- Department of Spinal Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510405, China.
- Laboratory Affiliated to National Key Discipline of Orthopaedic and Traumatology of Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, 510405, China.
| |
Collapse
|