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Cox JEJ, Pham KD, Keck AW, Wright Z, Thomas MA, Freeman WM, Ocañas SR. Flow Cytometry Analysis of Microglial Phenotypes in the Murine Brain During Aging and Disease. Bio Protoc 2024; 14:e5018. [PMID: 38948260 PMCID: PMC11211077 DOI: 10.21769/bioprotoc.5018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 05/19/2024] [Accepted: 05/28/2024] [Indexed: 07/02/2024] Open
Abstract
Microglia, the brain's primary resident immune cell, exists in various phenotypic states depending on intrinsic and extrinsic signaling. Distinguishing between these phenotypes can offer valuable biological insights into neurodevelopmental and neurodegenerative processes. Recent advances in single-cell transcriptomic profiling have allowed for increased granularity and better separation of distinct microglial states. While techniques such as immunofluorescence and single-cell RNA sequencing (scRNA-seq) are available to differentiate microglial phenotypes and functions, these methods present notable limitations, including challenging quantification methods, high cost, and advanced analytical techniques. This protocol addresses these limitations by presenting an optimized cell preparation procedure that prevents ex vivo activation and a flow cytometry panel to distinguish four distinct microglial states from murine brain tissue. Following cell preparation, fluorescent antibodies were applied to label 1) homeostatic, 2) disease-associated (DAM), 3) interferon response (IRM), and 4) lipid-droplet accumulating (LDAM) microglia, based on gene markers identified in previous scRNA-Seq studies. Stained cells were analyzed by flow cytometry to assess phenotypic distribution as a function of age and sex. A key advantage of this procedure is its adaptability, allowing the panel provided to be enhanced using additional markers with an appropriate cell analyzer (i.e., Cytek Aurora 5 laser spectral flow cytometer) and interrogating different brain regions or disease models. Additionally, this protocol does not require microglial cell sorting, resulting in a relatively quick and straightforward experiment. Ultimately, this protocol can compare the distribution of microglial phenotypic states between various experimental groups, such as disease state or age, with a lower cost and higher throughput than scRNA-seq. Key features • Analysis of microglial phenotypes from murine brain without the need for cell sorting, imaging, or scRNA-seq. • This protocol can distinguish between homeostatic, disease-associated (DAM), lipid-droplet accumulating (LDAM), and interferon response (IRM) microglia from any murine brain region and/or disease model of interest. • This protocol can be modified to incorporate additional markers of interest or dyes when using a cell analyzer capable of multiple color detections.
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Affiliation(s)
- Jillian E. J. Cox
- Neuroscience Program, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Genes and Human Disease, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Kevin D. Pham
- Genes and Human Disease, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Alex W. Keck
- Genes and Human Disease, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Zsabre Wright
- Genes and Human Disease, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Manu A. Thomas
- Genes and Human Disease, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Willard M. Freeman
- Neuroscience Program, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Genes and Human Disease, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Sarah R. Ocañas
- Neuroscience Program, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Genes and Human Disease, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
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He Y, Fan Y, Ahmadpoor X, Wang Y, Li ZA, Zhu W, Lin H. Targeting lysosomal quality control as a therapeutic strategy against aging and diseases. Med Res Rev 2024. [PMID: 38711187 DOI: 10.1002/med.22047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Revised: 04/04/2024] [Accepted: 04/21/2024] [Indexed: 05/08/2024]
Abstract
Previously, lysosomes were primarily referred to as the digestive organelles and recycling centers within cells. Recent discoveries have expanded the lysosomal functional scope and revealed their critical roles in nutrient sensing, epigenetic regulation, plasma membrane repair, lipid transport, ion homeostasis, and cellular stress response. Lysosomal dysfunction is also found to be associated with aging and several diseases. Therefore, function of macroautophagy, a lysosome-dependent intracellular degradation system, has been identified as one of the updated twelve hallmarks of aging. In this review, we begin by introducing the concept of lysosomal quality control (LQC), which is a cellular machinery that maintains the number, morphology, and function of lysosomes through different processes such as lysosomal biogenesis, reformation, fission, fusion, turnover, lysophagy, exocytosis, and membrane permeabilization and repair. Next, we summarize the results from studies reporting the association between LQC dysregulation and aging/various disorders. Subsequently, we explore the emerging therapeutic strategies that target distinct aspects of LQC for treating diseases and combatting aging. Lastly, we underscore the existing knowledge gap and propose potential avenues for future research.
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Affiliation(s)
- Yuchen He
- Department of Orthopaedics, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Yishu Fan
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Xenab Ahmadpoor
- Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Yumin Wang
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Zhong Alan Li
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
- Center for Neuromusculoskeletal Restorative Medicine, Hong Kong Science Park, Shatin, NT, Hong Kong SAR, China
| | - Weihong Zhu
- Department of Orthopaedics, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
- Department of Orthopaedic Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Hang Lin
- Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Bioengineering, University of Pittsburgh Swanson School of Engineering, Pittsburgh, Pennsylvania, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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Chen D, Lou Q, Song XJ, Kang F, Liu A, Zheng C, Li Y, Wang D, Qun S, Zhang Z, Cao P, Jin Y. Microglia govern the extinction of acute stress-induced anxiety-like behaviors in male mice. Nat Commun 2024; 15:449. [PMID: 38200023 PMCID: PMC10781988 DOI: 10.1038/s41467-024-44704-6] [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: 03/08/2023] [Accepted: 01/02/2024] [Indexed: 01/12/2024] Open
Abstract
Anxiety-associated symptoms following acute stress usually become extinct gradually within a period of time. However, the mechanisms underlying how individuals cope with stress to achieve the extinction of anxiety are not clear. Here we show that acute restraint stress causes an increase in the activity of GABAergic neurons in the CeA (GABACeA) in male mice, resulting in anxiety-like behaviors within 12 hours; meanwhile, elevated GABACeA neuronal CX3CL1 secretion via MST4 (mammalian sterile-20-like kinase 4)-NF-κB-CX3CL1 signaling consequently activates microglia in the CeA. Activated microglia in turn inhibit GABACeA neuronal activity via the engulfment of their dendritic spines, ultimately leading to the extinction of anxiety-like behaviors induced by restraint stress. These findings reveal a dynamic molecular and cellular mechanism in which microglia drive a negative feedback to inhibit GABACeA neuronal activity, thus facilitating maintenance of brain homeostasis in response to acute stress.
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Grants
- 32025017 National Natural Science Foundation of China (National Science Foundation of China)
- 32121002 National Natural Science Foundation of China (National Science Foundation of China)
- 82101300 National Natural Science Foundation of China (National Science Foundation of China)
- U22A20305 National Natural Science Foundation of China (National Science Foundation of China)
- the National Key Research and Development Program of China (STI2030-Major Projects 2021ZD0203100), Plans for Major Provincial Science & Technology Projects (202303a07020002), the CAS Project for Young Scientists in Basic Research (YSBR-013), the Innovative Research Team of High-level Local Universities in Shanghai (SHSMU-ZDCX20211902), the Institute of Health and Medicine (OYZD20220007)
- the China National Postdoctoral Program for Innovative Talents (BX20220283), the China Postdoctoral Science Foundation (2023M733395)
- Youth Innovation Promotion Association CAS, CAS Collaborative Innovation Program of Hefei Science Center (2021HSC-CIP013), the Fundamental Research Funds for the Central Universities (WK9100000030), USTC Research Funds of the Double First-Class Initiative (YD9100002018), the Natural Science Foundation of Anhui Province (2208085J30), and USTC Tang Scholar.
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Affiliation(s)
- Danyang Chen
- Department of Anesthesiology, the First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China
| | - Qianqian Lou
- Department of Anesthesiology, the First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China
| | - Xiang-Jie Song
- Department of Anesthesiology, the First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China
| | - Fang Kang
- Department of Anesthesiology, the First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China
| | - An Liu
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, 230022, China
| | - Changjian Zheng
- Department of Anesthesiology, the First Affiliated Hospital of Wannan Medical College, Wuhu, 241002, China
| | - Yanhua Li
- Department of Anesthesiology, the First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China
| | - Di Wang
- Department of Anesthesiology, the First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China
| | - Sen Qun
- Stroke Center and Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China
| | - Zhi Zhang
- Department of Anesthesiology, the First Affiliated Hospital of USTC, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China.
- The Center for Advanced Interdisciplinary Science and Biomedicine, Institute of Health and Medicine, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China.
| | - Peng Cao
- Stroke Center and Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China.
| | - Yan Jin
- Stroke Center and Department of Neurology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China.
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