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Chae S, Lee HJ, Lee HE, Kim J, Jeong YJ, Lin Y, Kim HY, Leriche G, Ehrlich RS, Lingl SC, Seo MD, Lee YH, Yang J, Kim JI, Hoe HS. The dopamine analogue CA140 alleviates AD pathology, neuroinflammation, and rescues synaptic/cognitive functions by modulating DRD1 signaling or directly binding to Abeta. J Neuroinflammation 2024; 21:200. [PMID: 39129007 DOI: 10.1186/s12974-024-03180-x] [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: 07/10/2023] [Accepted: 07/17/2024] [Indexed: 08/13/2024] Open
Abstract
BACKGROUND We recently reported that the dopamine (DA) analogue CA140 modulates neuroinflammatory responses in lipopolysaccharide-injected wild-type (WT) mice and in 3-month-old 5xFAD mice, a model of Alzheimer's disease (AD). However, the effects of CA140 on Aβ/tau pathology and synaptic/cognitive function and its molecular mechanisms of action are unknown. METHODS To investigate the effects of CA140 on cognitive and synaptic function and AD pathology, 3-month-old WT mice or 8-month-old (aged) 5xFAD mice were injected with vehicle (10% DMSO) or CA140 (30 mg/kg, i.p.) daily for 10, 14, or 17 days. Behavioral tests, ELISA, electrophysiology, RNA sequencing, real-time PCR, Golgi staining, immunofluorescence staining, and western blotting were conducted. RESULTS In aged 5xFAD mice, a model of AD pathology, CA140 treatment significantly reduced Aβ/tau fibrillation, Aβ plaque number, tau hyperphosphorylation, and neuroinflammation by inhibiting NLRP3 activation. In addition, CA140 treatment downregulated the expression of cxcl10, a marker of AD-associated reactive astrocytes (RAs), and c1qa, a marker of the interaction of RAs with disease-associated microglia (DAMs) in 5xFAD mice. CA140 treatment also suppressed the mRNA levels of s100β and cxcl10, markers of AD-associated RAs, in primary astrocytes from 5xFAD mice. In primary microglial cells from 5xFAD mice, CA140 treatment increased the mRNA levels of markers of homeostatic microglia (cx3cr1 and p2ry12) and decreased the mRNA levels of a marker of proliferative region-associated microglia (gpnmb) and a marker of lipid-droplet-accumulating microglia (cln3). Importantly, CA140 treatment rescued scopolamine (SCO)-mediated deficits in long-term memory, dendritic spine number, and LTP impairment. In aged 5xFAD mice, these effects of CA140 treatment on cognitive/synaptic function and AD pathology were regulated by dopamine D1 receptor (DRD1)/Elk1 signaling. In primary hippocampal neurons and WT mice, CA140 treatment promoted long-term memory and dendritic spine formation via effects on DRD1/CaMKIIα and/or ERK signaling. CONCLUSIONS Our results indicate that CA140 improves neuronal/synaptic/cognitive function and ameliorates Aβ/tau pathology and neuroinflammation by modulating DRD1 signaling in primary hippocampal neurons, primary astrocytes/microglia, WT mice, and aged 5xFAD mice.
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Affiliation(s)
- Sehyun Chae
- Neurovascular Unit, Korea Brain Research Institute (KBRI), 61, Cheomdan-ro, Dong-gu, Daegu, 41068, Republic of Korea
| | - Hyun-Ju Lee
- Neurodegenerative Unit, Korea Brain Research Institute (KBRI), 61, Cheomdan-ro, Dong-gu, Daegu, 41068, Republic of Korea
| | - Ha-Eun Lee
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-Gil, Ulsan, 44919, Republic of Korea
| | - Jieun Kim
- Neurodegenerative Unit, Korea Brain Research Institute (KBRI), 61, Cheomdan-ro, Dong-gu, Daegu, 41068, Republic of Korea
| | - Yoo Joo Jeong
- Neurodegenerative Unit, Korea Brain Research Institute (KBRI), 61, Cheomdan-ro, Dong-gu, Daegu, 41068, Republic of Korea
- Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu, 42988, Republic of Korea
| | - Yuxi Lin
- Biopharmaceutical Research Center, Korea Basic Science Institute (KBSI), Ochang, ChungBuk, 28119, Republic of Korea
| | - Hye Yun Kim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-Gil, Ulsan, 44919, Republic of Korea
| | - Geoffray Leriche
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093-0358, USA
| | - Rachel S Ehrlich
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093-0358, USA
| | - Sascha Castro Lingl
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093-0358, USA
| | - Min-Duk Seo
- College of Pharmacy and Department of Molecular Science and Technology, Ajou University, Suwon, Gyeonggi, 16499, Republic of Korea
| | - Young-Ho Lee
- Biopharmaceutical Research Center, Korea Basic Science Institute (KBSI), Ochang, ChungBuk, 28119, Republic of Korea
- Bio-Analytical Science, University of Science and Technology (UST), Daejeon, 34113, Republic of Korea
- Department of Systems Biotechnology, Chung-Ang University, Gyeonggi , 17546, Republic of Korea
| | - Jerry Yang
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, 92093-0358, USA.
| | - Jae-Ick Kim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-Gil, Ulsan, 44919, Republic of Korea.
| | - Hyang-Sook Hoe
- Neurodegenerative Unit, Korea Brain Research Institute (KBRI), 61, Cheomdan-ro, Dong-gu, Daegu, 41068, Republic of Korea.
- Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu, 42988, Republic of Korea.
- Department of Neural Development and Disease, Korea Brain Research Institute (KBRI), 61 Cheomdan-ro, Dong-gu, Daegu, 41068, Republic of Korea.
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Kale MB, Bhondge HM, Wankhede NL, Shende PV, Thanekaer RP, Aglawe MM, Rahangdale SR, Taksande BG, Pandit SB, Upaganlawar AB, Umekar MJ, Kopalli SR, Koppula S. Navigating the intersection: Diabetes and Alzheimer's intertwined relationship. Ageing Res Rev 2024; 100:102415. [PMID: 39002642 DOI: 10.1016/j.arr.2024.102415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2024] [Revised: 07/06/2024] [Accepted: 07/06/2024] [Indexed: 07/15/2024]
Abstract
Alzheimer's disease (AD) and Diabetes mellitus (DM) exhibit comparable pathophysiological pathways. Genetic abnormalities in APP, PS-1, and PS-2 are linked to AD, with diagnostic aid from CSF and blood biomarkers. Insulin dysfunction, termed "type 3 diabetes mellitus" in AD, involves altered insulin signalling and neuronal shrinkage. Insulin influences beta-amyloid metabolism, exacerbating neurotoxicity in AD and amyloid production in DM. Both disorders display impaired glucose transporter expression, hastening cognitive decline. Mitochondrial dysfunction and Toll-like receptor 4-mediated inflammation worsen neurodegeneration in both diseases. ApoE4 raises disease risk, especially when coupled with dyslipidemia common in DM. Targeting shared pathways like insulin-degrading enzyme activation and HSP60 holds promise for therapeutic intervention. Recognizing these interconnected mechanisms underscores the imperative for developing tailored treatments addressing the overlapping pathophysiology of AD and DM, offering potential avenues for more effective management of both conditions.
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Affiliation(s)
- Mayur B Kale
- Smt. Kishoritai Bhoyar College of Pharmacy, Kamptee, Nagpur, Maharashtra 441002, India
| | | | - Nitu L Wankhede
- Smt. Kishoritai Bhoyar College of Pharmacy, Kamptee, Nagpur, Maharashtra 441002, India
| | - Prajwali V Shende
- Smt. Kishoritai Bhoyar College of Pharmacy, Kamptee, Nagpur, Maharashtra 441002, India
| | - Rushikesh P Thanekaer
- Smt. Kishoritai Bhoyar College of Pharmacy, Kamptee, Nagpur, Maharashtra 441002, India
| | - Manish M Aglawe
- Smt. Kishoritai Bhoyar College of Pharmacy, Kamptee, Nagpur, Maharashtra 441002, India
| | - Sandip R Rahangdale
- Smt. Kishoritai Bhoyar College of Pharmacy, Kamptee, Nagpur, Maharashtra 441002, India
| | - Brijesh G Taksande
- Smt. Kishoritai Bhoyar College of Pharmacy, Kamptee, Nagpur, Maharashtra 441002, India
| | - Sunil B Pandit
- SNJB's Shriman Sureshdada Jain College of Pharmacy, Neminagar, Chandwad, Nashik, Maharashtra, India
| | - Aman B Upaganlawar
- SNJB's Shriman Sureshdada Jain College of Pharmacy, Neminagar, Chandwad, Nashik, Maharashtra, India
| | - Milind J Umekar
- Smt. Kishoritai Bhoyar College of Pharmacy, Kamptee, Nagpur, Maharashtra 441002, India
| | - Spandana Rajendra Kopalli
- Department of Bioscience and Biotechnology, Sejong University, Gwangjin-gu, Seoul 05006, Republic of Korea
| | - Sushruta Koppula
- College of Biomedical and Health Sciences, Konkuk University, Chungju-Si, Chungcheongbuk Do 27478, Republic of Korea.
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Chmielarz M, Sobieszczańska B, Środa-Pomianek K. Metabolic Endotoxemia: From the Gut to Neurodegeneration. Int J Mol Sci 2024; 25:7006. [PMID: 39000116 PMCID: PMC11241432 DOI: 10.3390/ijms25137006] [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: 05/15/2024] [Revised: 06/22/2024] [Accepted: 06/23/2024] [Indexed: 07/16/2024] Open
Abstract
Metabolic endotoxemia is a severe health problem for residents in developed countries who follow a Western diet, disrupting intestinal microbiota and the whole organism's homeostasis. Although the effect of endotoxin on the human immune system is well known, its long-term impact on the human body, lasting many months or even years, is unknown. This is due to the difficulty of conducting in vitro and in vivo studies on the prolonged effect of endotoxin on the central nervous system. In this article, based on the available literature, we traced the path of endotoxin from the intestines to the blood through the intestinal epithelium and factors promoting the development of metabolic endotoxemia. The presence of endotoxin in the bloodstream and the inflammation it induces may contribute to lowering the blood-brain barrier, potentially allowing its penetration into the central nervous system; although, the theory is still controversial. Microglia, guarding the central nervous system, are the first line of defense and respond to endotoxin with activation, which may contribute to the development of neurodegenerative diseases. We traced the pro-inflammatory role of endotoxin in neurodegenerative diseases and its impact on the epigenetic regulation of microglial phenotypes.
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Affiliation(s)
- Mateusz Chmielarz
- Department of Microbiology, Wroclaw University of Medicine, Chalubinskiego 4 Street, 50-368 Wroclaw, Poland
| | - Beata Sobieszczańska
- Department of Microbiology, Wroclaw University of Medicine, Chalubinskiego 4 Street, 50-368 Wroclaw, Poland
| | - Kamila Środa-Pomianek
- Department of Biophysics and Neuroscience, Wroclaw University of Medicine, Chalubinskiego 3a, 50-368 Wroclaw, Poland
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Campolim CM, Schimenes BC, Veras MM, Kim YB, Prada PO. Air pollution accelerates the development of obesity and Alzheimer's disease: the role of leptin and inflammation - a mini-review. Front Immunol 2024; 15:1401800. [PMID: 38933275 PMCID: PMC11199417 DOI: 10.3389/fimmu.2024.1401800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2024] [Accepted: 05/29/2024] [Indexed: 06/28/2024] Open
Abstract
Air pollution is an urgent concern linked to numerous health problems in low- and middle-income countries, where 92% of air pollution-related deaths occur. Particulate matter 2.5 (PM2.5) is the most harmful component of air pollutants, increasing inflammation and changing gut microbiota, favoring obesity, type 2 diabetes, and Alzheimer's Disease (AD). PM2.5 contains lipopolysaccharides (LPS), which can activate the Toll-like receptor 4 (TLR4) signaling pathway. This pathway can lead to the release of pro-inflammatory markers, including interleukins, and suppressor of cytokine signaling-3 (SOCS3), which inhibits leptin action, a hormone that keeps the energy homeostasis. Leptin plays a role in preventing amyloid plaque deposition and hyperphosphorylation of tau-protein (p-tau), mechanisms involved in the neurodegeneration in AD. Approximately 50 million people worldwide are affected by dementia, with a significant proportion living in low-and middle-income countries. This number is expected to triple by 2050. This mini-review focuses on the potential impact of PM2.5 exposure on the TLR4 signaling pathway, its contribution to leptin resistance, and dysbiosis that exacerbates the link between obesity and AD.
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Affiliation(s)
- Clara Machado Campolim
- Department of Internal Medicine, School of Medical Science, State University of Campinas (UNICAMP), Campinas, SP, Brazil
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA, United States
| | | | - Mariana Matera Veras
- Laboratory of Environmental and Experimental Pathology LIM05, Department of Pathology, School of Medicine, University of São Paulo (USP), São Paulo, SP, Brazil
| | - Young-Bum Kim
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, MA, United States
| | - Patricia Oliveira Prada
- Department of Internal Medicine, School of Medical Science, State University of Campinas (UNICAMP), Campinas, SP, Brazil
- Obesity and Comorbidities Research Center, Campinas, SP, Brazil
- Department of Structural and Functional Biology, Institute of Biology (IB), University of Campinas, Campinas, SP, Brazil
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Zhang L, Xu F, Yang Y, Yang L, Wu Q, Sun H, An Z, Li J, Wu H, Song J, Wu W. PM 2.5 exposure upregulates pro-inflammatory protein expression in human microglial cells via oxidant stress and TLR4/NF-κB pathway. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 277:116386. [PMID: 38657455 DOI: 10.1016/j.ecoenv.2024.116386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 04/18/2024] [Accepted: 04/21/2024] [Indexed: 04/26/2024]
Abstract
Exposure to ambient PM2.5 is associated with neurodegenerative disorders, in which microglia activation plays a critical role. Thus far, the underlying mechanisms for PM2.5-induced microglia activation have not been well elucidated. In this study, a human microglial cell line (HMC3) was used as the in vitro model to examine the inflammatory effect (hall marker of microglia activation) of PM2.5 and regulatory pathways. The expression of inflammatory mediators including interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) as well as the brain derived neurotrophic factor (BDNF) were determined by ELISA and/or real-time PCR, respectively. Flow cytometry was used to measure the production of intracellular reactive oxygen species (ROS). Western blot was used to measure protein levels of Toll-like receptor 4 (TLR4), NF-κB inhibitor α (IκBα) and COX-2. It was shown that PM2.5 stimulation increased IL-6 and COX-2 expression but decreased BDNF expression in a dose-dependent manner. Further studies showed that PM2.5 triggered the formation of ROS and pre-treatment with the ROS scavenger acetylcysteine (NAC) significantly suppressed PM2.5-induced IL-6 and COX-2 expression. Moreover, the nuclear factor kappa B (NF-κB) inhibitor BAY11-7085 or the TLR4 neutralizing antibody markedly blocked PM2.5-induced IL-6 and COX-2 expression. However, NAC or BAY11-7085 exhibited minimal effect on PM2.5-induced BDNF down-regulation. In addition, pre-treatment with BAY11-7085 or TLR4 neutralizing antibody reduced ROS production induced by PM2.5, and NAC pre-treatment inhibited TLR4 expression and NF-κB activation induced by PM2.5. Collectively, PM2.5 treatment induced IL-6 and COX-2 but suppressed BDNF expression. PM2.5-induced IL-6 and COX-2 expression was mediated by interactive oxidative stress and TLR4/NF-κB pathway.
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Affiliation(s)
- Ling Zhang
- Henan International Collaborative Laboratory for Health Effects and Intervention of Air Pollution, School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Fei Xu
- Henan International Collaborative Laboratory for Health Effects and Intervention of Air Pollution, School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Yishu Yang
- Henan International Collaborative Laboratory for Health Effects and Intervention of Air Pollution, School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Lin Yang
- Henan International Collaborative Laboratory for Health Effects and Intervention of Air Pollution, School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Qiong Wu
- Henan International Collaborative Laboratory for Health Effects and Intervention of Air Pollution, School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Han Sun
- Henan International Collaborative Laboratory for Health Effects and Intervention of Air Pollution, School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Zhen An
- Henan International Collaborative Laboratory for Health Effects and Intervention of Air Pollution, School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Juan Li
- Henan International Collaborative Laboratory for Health Effects and Intervention of Air Pollution, School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Hui Wu
- Henan International Collaborative Laboratory for Health Effects and Intervention of Air Pollution, School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Jie Song
- Henan International Collaborative Laboratory for Health Effects and Intervention of Air Pollution, School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Weidong Wu
- Henan International Collaborative Laboratory for Health Effects and Intervention of Air Pollution, School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China.
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Islam R, Rajan R, Choudhary H, Vrionis F, Hanafy KA. Gender differences in Alzheimer's may be associated with TLR4-LYN expression in damage associated microglia and neuronal phagocytosis. J Cell Physiol 2024; 239:e30916. [PMID: 36409648 PMCID: PMC10199960 DOI: 10.1002/jcp.30916] [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: 07/20/2022] [Revised: 11/03/2022] [Accepted: 11/07/2022] [Indexed: 11/22/2022]
Abstract
The role of Aβ plaques and neurofibrillary tangles in Alzheimer's disease (AD) pathogenesis have recently come into question due to failure of many pharmaceutical agents targeting these deposits and detection of these misfolded proteins in normal human brains. Therefore, we investigated correlations between microglial activation and toll like receptor 4 (TLR4) and Lck/Yes novel tyrosine (LYN) kinase signaling in an AD mouse model. In this study, we used 5-6-month-old 5XFAD and wild type (WT) male and female mice. Immunohistochemistry (IHC) and flow cytometry (FC) were performed on their brains. Cognitive performance was assessed with the Barnes-Maze. IHC showed more Ab aggregation in microglia of female 5XFAD mice compared to their male counterparts. Increased co-localization of microglial TLR4 and LYN was also observed in AD more than WT and females more than males. IHC also suggests microglial phagocytosis of neurons in AD mice, which is supported by FC data. Our FC data also support the involvement of disease associated microglia (DAMs) in this process based on cytokine secretion. Cognitive assessment by the Barnes maze showed 5XFAD females performed worse than males. In this study, we investigated the relationship between microglial TLR4 and LYN kinase in 5XFAD male and females. Our data reveals a correlation between microglial TLR4 and LYN co-localization and AD pathogenesis, more in females than males. Targeting microglial TLR4 and Lyn in DAMs may offer new therapeutic opportunities in the treatment of AD.
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Affiliation(s)
- Rezwanul Islam
- Department of Biomedical Sciences, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL
| | - Robin Rajan
- Marcus Neuroscience Institute, Boca Raton Medical Center, Boca Raton, FL
| | - Hadi Choudhary
- Department of Biomedical Sciences, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL
| | - Frank Vrionis
- Marcus Neuroscience Institute, Boca Raton Medical Center, Boca Raton, FL
| | - Khalid A. Hanafy
- Department of Biomedical Sciences, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL
- Marcus Neuroscience Institute, Boca Raton Medical Center, Boca Raton, FL
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Wang J, Behl T, Rana T, Sehgal A, Wal P, Saxena B, Yadav S, Mohan S, Anwer MK, Chigurupati S, Zaheer I, Shen B, Singla RK. Exploring the pathophysiological influence of heme oxygenase-1 on neuroinflammation and depression: A study of phytotherapeutic-based modulation. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2024; 127:155466. [PMID: 38461764 DOI: 10.1016/j.phymed.2024.155466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 02/02/2024] [Accepted: 02/18/2024] [Indexed: 03/12/2024]
Abstract
BACKGROUND The heme oxygenase (HO) system plays a significant role in neuroprotection and reduction of neuroinflammation and neurodegeneration. The system, via isoforms HO-1 and HO-2, regulates cellular redox balance. HO-1, an antioxidant defense enzyme, is highlighted due to its association with depression, characterized by heightened neuroinflammation and impaired oxidative stress responses. METHODOLOGY We observed the pathophysiology of HO-1 and phytochemicals as its modulator. We explored Science Direct, Scopus, and PubMed for a comprehensive literature review. Bibliometric and temporal trend analysis were done using VOSviewer. RESULTS Several phytochemicals can potentially alleviate neuroinflammation and oxidative stress-induced depressive symptoms. These effects result from inhibiting the MAPK and NK-κB pathways - both implicated in the overproduction of pro-inflammatory factors - and from the upregulation of HO-1 expression mediated by Nrf2. Bibliometric and temporal trend analysis further validates these associations. CONCLUSION In summary, our findings suggest that antidepressant agents can mitigate neuroinflammation and depressive disorder pathogenesis via the upregulation of HO-1 expression. These agents suppress pro-inflammatory mediators and depressive-like symptoms, demonstrating that HO-1 plays a significant role in the neuroinflammatory process and the development of depression.
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Affiliation(s)
- Jiao Wang
- Joint Laboratory of Artificial Intelligence for Critical Care Medicine, Department of Critical Care Medicine and Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, China; Department of Computer Science and Information Technology, University of A Coruña, A Coruña, Spain
| | - Tapan Behl
- Amity School of Pharmaceutical Sciences, Amity University, Mohali, Punjab, India.
| | - Tarapati Rana
- Chitkara College of Pharmacy, Chitkara University, Rajpura-140401, Punjab, India; Government Pharmacy College, Seraj-175123, Mandi, Himachal Pradesh, India
| | - Aayush Sehgal
- GHG Khalsa College of Pharmacy, Gurusar Sadhar-141104, Ludhiana, Punjab, India
| | - Pranay Wal
- Pranveer Singh Institute of Technology, Pharmacy, Kanpur, Uttar Pradesh, India
| | - Bhagawati Saxena
- Department of Pharmacology, Institute of Pharmacy, Nirma University, S.G. Highway, Ahmedabad, 382481, India
| | - Shivam Yadav
- School of Pharmacy, Babu Banarasi Das University, Lucknow, Uttar Pradesh, India
| | - Syam Mohan
- Substance Abuse and Toxicology Research Center, Jazan University, Jazan 45142, Saudi Arabia; School of Health Sciences, University of Petroleum and Energy Studies, Dehradun, 248007, Uttarakhand, India; Center for Global Health Research, Saveetha Medical College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, India
| | - Md Khalid Anwer
- Department of Pharmaceutics, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj-11942, Saudi Arabia
| | - Sridevi Chigurupati
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, Qassim University, Buraydah-51452, Kingdom of Saudi Arabia; Department of Biotechnology, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Saveetha Nagar, Thandalam, Chennai-602105, India
| | - Imran Zaheer
- Department of Pharmacology, College of Medicine, (Al-Dawadmi Campus), Shaqra University, Al-Dawadmi, 11961, Kingdom of Saudi Arabia
| | - Bairong Shen
- Joint Laboratory of Artificial Intelligence for Critical Care Medicine, Department of Critical Care Medicine and Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, China.
| | - Rajeev K Singla
- Joint Laboratory of Artificial Intelligence for Critical Care Medicine, Department of Critical Care Medicine and Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, China; School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab-144411, India.
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Ouyang P, Cai Z, Peng J, Lin S, Chen X, Chen C, Feng Z, Wang L, Song G, Zhang Z. SELENOK-dependent CD36 palmitoylation regulates microglial functions and Aβ phagocytosis. Redox Biol 2024; 70:103064. [PMID: 38320455 PMCID: PMC10850786 DOI: 10.1016/j.redox.2024.103064] [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: 01/09/2024] [Revised: 01/25/2024] [Accepted: 01/25/2024] [Indexed: 02/08/2024] Open
Abstract
Amyloid-beta (Aβ) is a key factor in the onset and progression of Alzheimer's disease (AD). Selenium (Se) compounds show promise in AD treatment. Here, we revealed that selenoprotein K (SELENOK), a selenoprotein involved in immune regulation and potentially related to AD pathology, plays a critical role in microglial immune response, migration, and phagocytosis. In vivo and in vitro studies corroborated that SELENOK deficiency inhibits microglial Aβ phagocytosis, exacerbating cognitive deficits in 5xFAD mice, which are reversed by SELENOK overexpression. Mechanistically, SELENOK is involved in CD36 palmitoylation through DHHC6, regulating CD36 localization to microglial plasma membranes and thus impacting Aβ phagocytosis. CD36 palmitoylation was reduced in the brains of patients and mice with AD. Se supplementation promoted SELENOK expression and CD36 palmitoylation, enhancing microglial Aβ phagocytosis and mitigating AD progression. We have identified the regulatory mechanisms from Se-dependent selenoproteins to Aβ pathology, providing novel insights into potential therapeutic strategies involving Se and selenoproteins.
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Affiliation(s)
- Pei Ouyang
- Shenzhen Key Laboratory of Marine Bioresources and Ecology, Brain Disease and Big Data Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China; Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China
| | - Zhiyu Cai
- Shenzhen Key Laboratory of Marine Bioresources and Ecology, Brain Disease and Big Data Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Jiaying Peng
- Shenzhen Key Laboratory of Marine Bioresources and Ecology, Brain Disease and Big Data Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Shujing Lin
- Shenzhen Key Laboratory of Marine Bioresources and Ecology, Brain Disease and Big Data Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Xiaochun Chen
- Shenzhen Key Laboratory of Marine Bioresources and Ecology, Brain Disease and Big Data Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Changbin Chen
- Shenzhen Key Laboratory of Marine Bioresources and Ecology, Brain Disease and Big Data Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Ziqi Feng
- Shenzhen Key Laboratory of Marine Bioresources and Ecology, Brain Disease and Big Data Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Lin Wang
- College of Biology and Food Engineering, Anyang Institute of Technology, Anyang, China
| | - Guoli Song
- Shenzhen Key Laboratory of Marine Bioresources and Ecology, Brain Disease and Big Data Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China; Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.
| | - Zhonghao Zhang
- Shenzhen Key Laboratory of Marine Bioresources and Ecology, Brain Disease and Big Data Research Institute, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China; Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, China.
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9
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Karati D, Mukherjee S, Roy S. A Promising Drug Candidate as Potent Therapeutic Approach for Neuroinflammation and Its In Silico Justification of Chalcone Congeners: a Comprehensive Review. Mol Neurobiol 2024; 61:1873-1891. [PMID: 37801205 DOI: 10.1007/s12035-023-03632-0] [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: 06/13/2023] [Accepted: 08/31/2023] [Indexed: 10/07/2023]
Abstract
Multiple genetic, environmental, and immunological variables cause neuropsychiatric disorders (NPDs). The induced inflammatory immune response is also connected to the severity and treatment outcomes of various NPDs. These reactions also significantly impact numerous brain functions such as GABAergic signaling and neurotransmitter synthesis through inflammatory cytokines and chemokines. Chalcones (1,3-diaryl-2-propen-1-ones) and their heterocyclic counterparts are flavonoids with various biological characteristics including anti-inflammatory activity. Several pure chalcones have been clinically authorized or studied in humans. Chalcones are favored for their diagnostic and therapeutic efficacy in neuroinflammation due to their tiny molecular size, easy manufacturing, and flexibility for changes to adjust lipophilicity ideal for BBB penetrability. These compounds reached an acceptable plasma concentration and were well-tolerated in clinical testing. As a result, they are attracting increasing attention from scientists. However, chalcones' therapeutic potential remains largely untapped. This paper is aimed at highlighting the causes of neuroinflammation, more potent chalcone congeners, their mechanisms of action, and relevant structure-activity relationships.
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Affiliation(s)
- Dipanjan Karati
- Department of Pharmaceutical Technology, School of Pharmacy, Techno India University, Kolkata, West Bengal, 700091, India
| | - Swarupananda Mukherjee
- Department of Pharmaceutical Technology, NSHM Knowledge Campus, Kolkata, 124 B.L. Saha Road, Kolkata, West Bengal, 700053, India
| | - Souvik Roy
- Department of Pharmaceutical Technology, NSHM Knowledge Campus, Kolkata, 124 B.L. Saha Road, Kolkata, West Bengal, 700053, India.
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10
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Djurišić M. Immune receptors and aging brain. Biosci Rep 2024; 44:BSR20222267. [PMID: 38299364 PMCID: PMC10866841 DOI: 10.1042/bsr20222267] [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: 07/20/2023] [Revised: 01/08/2024] [Accepted: 01/29/2024] [Indexed: 02/02/2024] Open
Abstract
Aging brings about a myriad of degenerative processes throughout the body. A decrease in cognitive abilities is one of the hallmark phenotypes of aging, underpinned by neuroinflammation and neurodegeneration occurring in the brain. This review focuses on the role of different immune receptors expressed in cells of the central and peripheral nervous systems. We will discuss how immune receptors in the brain act as sentinels and effectors of the age-dependent shift in ligand composition. Within this 'old-age-ligand soup,' some immune receptors contribute directly to excessive synaptic weakening from within the neuronal compartment, while others amplify the damaging inflammatory environment in the brain. Ultimately, chronic inflammation sets up a positive feedback loop that increases the impact of immune ligand-receptor interactions in the brain, leading to permanent synaptic and neuronal loss.
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Affiliation(s)
- Maja Djurišić
- Departments of Biology, Neurobiology, and Bio-X, Stanford University, Stanford, CA 94305, U.S.A
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11
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Xu X, Han Y, Zhang B, Ren Q, Ma J, Liu S. Understanding immune microenvironment alterations in the brain to improve the diagnosis and treatment of diverse brain diseases. Cell Commun Signal 2024; 22:132. [PMID: 38368403 PMCID: PMC10874090 DOI: 10.1186/s12964-024-01509-w] [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: 09/25/2023] [Accepted: 02/01/2024] [Indexed: 02/19/2024] Open
Abstract
Abnormal inflammatory states in the brain are associated with a variety of brain diseases. The dynamic changes in the number and function of immune cells in cerebrospinal fluid (CSF) are advantageous for the early prediction and diagnosis of immune diseases affecting the brain. The aggregated factors and cells in inflamed CSF may represent candidate targets for therapy. The physiological barriers in the brain, such as the blood‒brain barrier (BBB), establish a stable environment for the distribution of resident immune cells. However, the underlying mechanism by which peripheral immune cells migrate into the brain and their role in maintaining immune homeostasis in CSF are still unclear. To advance our understanding of the causal link between brain diseases and immune cell status, we investigated the characteristics of immune cell changes in CSF and the molecular mechanisms involved in common brain diseases. Furthermore, we summarized the diagnostic and treatment methods for brain diseases in which immune cells and related cytokines in CSF are used as targets. Further investigations of the new immune cell subtypes and their contributions to the development of brain diseases are needed to improve diagnostic specificity and therapy.
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Affiliation(s)
- Xiaotong Xu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Yi Han
- Guang'an Men Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, People's Republic of China.
| | - Binlong Zhang
- Guang'an Men Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, People's Republic of China
| | - Quanzhong Ren
- JST Sarcopenia Research Centre, National Center for Orthopaedics, Beijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan Hospital, Capital Medical University, Beijing, 100035, People's Republic of China
| | - Juan Ma
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, People's Republic of China.
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
| | - Sijin Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
- Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, Shandong, 250117, People's Republic of China
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12
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Tsai ST, Yang CC, Liao HY, Lin YW. Electroacupuncture Reduces Fibromyalgia Pain via Neuronal/Microglial Inactivation and Toll-like Receptor 4 in the Mouse Brain: Precise Interpretation of Chemogenetics. Biomedicines 2024; 12:387. [PMID: 38397989 PMCID: PMC10886830 DOI: 10.3390/biomedicines12020387] [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: 01/22/2024] [Revised: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/25/2024] Open
Abstract
Fibromyalgia (FM) is a complex, chronic, widespread pain syndrome that can cause significant health and economic burden. Emerging evidence has shown that neuroinflammation is an underlying pathological mechanism in FM. Toll-like receptors (TLRs) are key mediators of the immune system. TLR4 is expressed primarily in microglia and regulates downstream signaling pathways, such as MyD88/NF-κB and TRIF/IRF3. It remains unknown whether electroacupuncture (EA) has therapeutic benefit in attenuating FM pain and what role the TLR4 pathway may play in this effect. We compared EA with sham EA to eliminate the placebo effect due to acupuncture. We demonstrated that intermittent cold stress significantly induced an increase in mechanical and thermal FM pain in mice (mechanical: 2.48 ± 0.53 g; thermal: 5.64 ± 0.32 s). EA but not sham EA has an analgesic effect on FM mice. TLR4 and inflammatory mediator-related molecules were increased in the thalamus, medial prefrontal cortex, somatosensory cortex (SSC), and amygdala of FM mice, indicating neuroinflammation and microglial activation. These molecules were reduced by EA but not sham EA. Furthermore, a new chemogenetics method was used to precisely inhibit SSC activity that displayed an anti-nociceptive effect through the TLR4 pathway. Our results imply that the analgesic effect of EA is associated with TLR4 downregulation. We provide novel evidence that EA modulates the TLR4 signaling pathway, revealing potential therapeutic targets for FM pain.
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Affiliation(s)
- Sheng-Ta Tsai
- Department of Neurology, China Medical University Hospital, Taichung 404332, Taiwan;
- School of Medicine, China Medical University, Taichung 404328, Taiwan
| | - Chia-Chun Yang
- Department of General Psychiatry, Taoyuan Psychiatric Center, Ministry of Health and Welfare, Taoyuan 330035, Taiwan;
| | - Hsien-Yin Liao
- School of Post-Baccalaureate Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 404328, Taiwan
- Department of Acupuncture, China Medical University Hospital, Taichung 404328, Taiwan
| | - Yi-Wen Lin
- Graduate Institute of Acupuncture Science, College of Chinese Medicine, China Medical University, Taichung 404328, Taiwan
- Chinese Medicine Research Center, China Medical University, Taichung 404328, Taiwan
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13
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Choi S, Choi SH, Bastola T, Park Y, Oh J, Kim KY, Hwang S, Miller YI, Ju WK. AIBP: A New Safeguard against Glaucomatous Neuroinflammation. Cells 2024; 13:198. [PMID: 38275823 PMCID: PMC10814024 DOI: 10.3390/cells13020198] [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: 12/11/2023] [Revised: 01/18/2024] [Accepted: 01/20/2024] [Indexed: 01/27/2024] Open
Abstract
Glaucoma is a group of ocular diseases that cause irreversible blindness. It is characterized by multifactorial degeneration of the optic nerve axons and retinal ganglion cells (RGCs), resulting in the loss of vision. Major components of glaucoma pathogenesis include glia-driven neuroinflammation and impairment of mitochondrial dynamics and bioenergetics, leading to retinal neurodegeneration. In this review article, we summarize current evidence for the emerging role of apolipoprotein A-I binding protein (AIBP) as an important anti-inflammatory and neuroprotective factor in the retina. Due to its association with toll-like receptor 4 (TLR4), extracellular AIBP selectively removes excess cholesterol from the plasma membrane of inflammatory and activated cells. This results in the reduced expression of TLR4-associated, cholesterol-rich lipid rafts and the inhibition of downstream inflammatory signaling. Intracellular AIBP is localized to mitochondria and modulates mitophagy through the ubiquitination of mitofusins 1 and 2. Importantly, elevated intraocular pressure induces AIBP deficiency in mouse models and in human glaucomatous retina. AIBP deficiency leads to the activation of TLR4 in Müller glia, triggering mitochondrial dysfunction in both RGCs and Müller glia, and compromising visual function in a mouse model. Conversely, restoring AIBP expression in the retina reduces neuroinflammation, prevents RGCs death, and protects visual function. These results provide new insight into the mechanism of AIBP function in the retina and suggest a therapeutic potential for restoring retinal AIBP expression in the treatment of glaucoma.
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Affiliation(s)
- Seunghwan Choi
- Hamilton Glaucoma Center and Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA 92093, USA; (S.C.); (T.B.); (Y.P.)
| | - Soo-Ho Choi
- Department of Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | - Tonking Bastola
- Hamilton Glaucoma Center and Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA 92093, USA; (S.C.); (T.B.); (Y.P.)
| | - Younggun Park
- Hamilton Glaucoma Center and Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA 92093, USA; (S.C.); (T.B.); (Y.P.)
- Department of Ophthalmology and Visual Science, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
| | - Jonghyun Oh
- Hamilton Glaucoma Center and Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA 92093, USA; (S.C.); (T.B.); (Y.P.)
- Department of Ophthalmology, Dongguk University Ilsan Hospital, Goyang 10326, Republic of Korea
| | - Keun-Young Kim
- National Center for Microscopy and Imaging Research, Department of Neurosciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Sinwoo Hwang
- Hamilton Glaucoma Center and Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA 92093, USA; (S.C.); (T.B.); (Y.P.)
| | - Yury I. Miller
- Department of Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | - Won-Kyu Ju
- Hamilton Glaucoma Center and Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA 92093, USA; (S.C.); (T.B.); (Y.P.)
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14
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Yedke NG, Kumar P. The Neuroprotective Role of BCG Vaccine in Movement Disorders: A Review. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2024; 23:30-38. [PMID: 36567299 DOI: 10.2174/1871527322666221223142813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 11/07/2022] [Accepted: 11/10/2022] [Indexed: 12/27/2022]
Abstract
Bacillus Calmette-Guérin (BCG) is the first developed vaccine to prevent tuberculosis (TB) and is the world's most widely used vaccine. It has a reconcilable defense in opposition to tuberculosis, meningitis, and miliary disease in children but changeable protection against pulmonary TB. Immune activation is responsible for regulating neural development by activating it. The effect of the BCG vaccine on neuronal disorders due to subordinate immune provocation is useful. BCG vaccine can prevent neuronal degeneration in different neurological disorders by provoking auto-reactive T-cells. In the case of TB, CD4+ T-cells effectively protect the immune response by protecting the central defense. Because of the preceding fact, BCG induces protection by creating precise T-cells like CD4+ T-cells and CD8+ T-cells. Hence, vaccination-induced protection generates specific T-cells and CD4+ T-cells, and CD8+ T-cells. The BCG vaccine may have an essential effect on motor disorders and play a crucial role in neuroprotective management. The present review describes how the BCG vaccine might be interrelated with motor disorders and play a key role in such diseases.
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Affiliation(s)
- Narhari Gangaram Yedke
- Department of Pharmaceutical Sciences and Technology Maharaja Ranjit Singh Punjab Technical University, Bathinda, Punjab, India
| | - Puneet Kumar
- Department of Pharmacology Central University of Punjab, Bathinda, Punjab, India
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15
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Li Y, Chen X, Zhou M, Feng S, Peng X, Wang Y. Microglial TLR4/NLRP3 Inflammasome Signaling in Alzheimer's Disease. J Alzheimers Dis 2024; 97:75-88. [PMID: 38043010 DOI: 10.3233/jad-230273] [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] [Indexed: 12/04/2023]
Abstract
Alzheimer's disease is a pervasive neurodegenerative disease that is estimated to represent approximately 70% of dementia cases worldwide, and the molecular complexity that has been highlighted remains poorly understood. The accumulation of extracellular amyloid-β (Aβ), intracellular neurofibrillary tangles formed by tau hyperphosphorylation, and neuroinflammation are the major pathological features of Alzheimer's disease (AD). Over the years, there has been no apparent breakthrough in drug discovery based on the Aβ and tau hypotheses. Neuroinflammation has gradually become a hot spot in AD treatment research. As the primary cells of innate immunity in the central nervous system, microglia play a key role in neuroinflammation. Toll-like receptor 4 (TLR4) and nucleotide-binding oligomerization domain-like receptor 3 (NLRP3) inflammasomes are vital molecules in neuroinflammation. In the pathological context of AD, the complex interplay between TLR4 and the NLRP3 inflammasomes in microglia influences AD pathology via neuroinflammation. In this review, the effect of the activation and inhibition of TLR4 and NLRP3 in microglia on AD pathology, as well as the cross-talk between TLR4 and the NLRP3 inflammasome, and the influence of essential molecules in the relevant signaling pathway on AD pathology, were expounded. In addition, the feasibility of these factors in representing a potential treatment option for AD has been clarified.
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Affiliation(s)
- Yunfeng Li
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
- Department of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Xiongjin Chen
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
- Department of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Mulan Zhou
- Department of Pharmacy, The People's Hospital of Gaozhou, Maoming, China
| | - Sifan Feng
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
- Department of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Xiaoping Peng
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
- Department of Neurology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Yan Wang
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
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16
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Xu J, Chen Y, Shi Y, Sun A, Yang Y, Boustani M, Su J, Zhang P. Associations Between Neuroinflammation-Related Conditions and Alzheimer's Disease: A Study of US Insurance Claims Data. J Alzheimers Dis 2024; 99:739-752. [PMID: 38701142 PMCID: PMC11228456 DOI: 10.3233/jad-231286] [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] [Indexed: 05/05/2024]
Abstract
Background Early detection of Alzheimer's disease (AD) is a key component for the success of the recently approved lecanemab and aducanumab. Patients with neuroinflammation-related conditions are associated with a higher risk for developing AD. Objective Investigate the incidence of AD among patients with neuroinflammation-related conditions including epilepsy, hemorrhage stroke, multiple sclerosis (MS), and traumatic brain injury (TBI). Methods We used Optum's de-identified Clinformatics Data Mart Database (CDM). We derived covariate-matched cohorts including patients with neuroinflammation-related conditions and controls without the corresponding condition. The matched cohorts were: 1) patients with epilepsy and controls (N = 67,825 matched pairs); 2) patients with hemorrhage stroke and controls (N = 81,510 matched pairs); 3) patients with MS and controls (N = 9,853 matched pairs); and 4) patients TBI and controls (N = 104,637 matched pairs). We used the Cox model to investigate the associations between neuroinflammation-related conditions and AD. Results We identified that epilepsy, hemorrhage stroke, and TBI were associated with increased risks of AD in both males and females (hazard ratios [HRs]≥1.74, p < 0.001), as well as in gender- and race-conscious subpopulations (HRs≥1.64, p < 0.001). We identified that MS was associated with increased risks of AD in both males and females (HRs≥1.47, p≤0.004), while gender- and race-conscious subgroup analysis shown mixed associations. Conclusions Patients with epilepsy, hemorrhage stroke, MS, and/or TBI are associated with a higher risk of developing AD. More attention on cognitive status should be given to older patients with these conditions.
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Affiliation(s)
- Jing Xu
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yao Chen
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yi Shi
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Anna Sun
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yuedi Yang
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Malaz Boustani
- Indiana University Center for Health Innovation and Implementation Science, School of Medicine, Indianapolis, IN, USA
| | - Jing Su
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Pengyue Zhang
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, IN, USA
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Hao W, Luo Q, Tomic I, Quan W, Hartmann T, Menger MD, Fassbender K, Liu Y. Modulation of Alzheimer's disease brain pathology in mice by gut bacterial depletion: the role of IL-17a. Gut Microbes 2024; 16:2363014. [PMID: 38904096 PMCID: PMC11195493 DOI: 10.1080/19490976.2024.2363014] [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: 12/07/2023] [Accepted: 05/29/2024] [Indexed: 06/22/2024] Open
Abstract
Gut bacteria regulate brain pathology of Alzheimer's disease (AD) patients and animal models; however, the underlying mechanism remains unclear. In this study, 3-month-old APP-transgenic female mice with and without knock-out of Il-17a gene were treated with antibiotics-supplemented or normal drinking water for 2 months. The antibiotic treatment eradicated almost all intestinal bacteria, which led to a reduction in Il-17a-expressing CD4-positive T lymphocytes in the spleen and gut, and to a decrease in bacterial DNA in brain tissue. Depletion of gut bacteria inhibited inflammatory activation in both brain tissue and microglia, lowered cerebral Aβ levels, and promoted transcription of Arc gene in the brain of APP-transgenic mice, all of which effects were abolished by deficiency of Il-17a. As possible mechanisms regulating Aβ pathology, depletion of gut bacteria inhibited β-secretase activity and increased the expression of Abcb1 and Lrp1 in the brain or at the blood-brain barrier, which were also reversed by the absence of Il-17a. Interestingly, a crossbreeding experiment between APP-transgenic mice and Il-17a knockout mice further showed that deficiency of Il-17a had already increased Abcb1 and Lrp1 expression at the blood-brain barrier. Thus, depletion of gut bacteria attenuates inflammatory activation and amyloid pathology in APP-transgenic mice via Il-17a-involved signaling pathways. Our study contributes to a better understanding of the gut-brain axis in AD pathophysiology and highlights the therapeutic potential of Il-17a inhibition or specific depletion of gut bacteria that stimulate the development of Il-17a-expressing T cells.
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Affiliation(s)
- Wenlin Hao
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
| | - Qinghua Luo
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
- Department of Neurology, The second affiliated hospital of Nanchang University, Nanchang, China
| | - Inge Tomic
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
| | - Wenqiang Quan
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
- Department of Clinical Laboratory, Tongji Hospital, Tongji University Medical School, Shanghai, China
| | - Tobias Hartmann
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
- Department of Experimental Neurology, Saarland University, Homburg/Saar, Germany
| | - Michael D. Menger
- Department of Experimental Surgery, Saarland University, Homburg/Saar, Germany
| | - Klaus Fassbender
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
| | - Yang Liu
- Department of Neurology, Saarland University, Homburg/Saar, Germany
- German Institute for Dementia Prevention (DIDP), Saarland University, Homburg/Saar, Germany
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18
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Terzioglu G, Young-Pearse TL. Microglial function, INPP5D/SHIP1 signaling, and NLRP3 inflammasome activation: implications for Alzheimer's disease. Mol Neurodegener 2023; 18:89. [PMID: 38017562 PMCID: PMC10685641 DOI: 10.1186/s13024-023-00674-9] [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: 04/05/2023] [Accepted: 10/26/2023] [Indexed: 11/30/2023] Open
Abstract
Recent genetic studies on Alzheimer's disease (AD) have brought microglia under the spotlight, as loci associated with AD risk are enriched in genes expressed in microglia. Several of these genes have been recognized for their central roles in microglial functions. Increasing evidence suggests that SHIP1, the protein encoded by the AD-associated gene INPP5D, is an important regulator of microglial phagocytosis and immune response. A recent study from our group identified SHIP1 as a negative regulator of the NLRP3 inflammasome in human iPSC-derived microglial cells (iMGs). In addition, we found evidence for a connection between SHIP1 activity and inflammasome activation in the AD brain. The NLRP3 inflammasome is a multiprotein complex that induces the secretion of pro-inflammatory cytokines as part of innate immune responses against pathogens and endogenous damage signals. Previously published studies have suggested that the NLRP3 inflammasome is activated in AD and contributes to AD-related pathology. Here, we provide an overview of the current understanding of the microglial NLRP3 inflammasome in the context of AD-related inflammation. We then review the known intracellular functions of SHIP1, including its role in phosphoinositide signaling, interactions with microglial phagocytic receptors such as TREM2 and evidence for its intersection with NLRP3 inflammasome signaling. Through rigorous examination of the intricate connections between microglial signaling pathways across several experimental systems and postmortem analyses, the field will be better equipped to tailor newly emerging therapeutic strategies targeting microglia in neurodegenerative diseases.
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Affiliation(s)
- Gizem Terzioglu
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, 60 Fenwood Rd, Boston, MA, 02115, USA
| | - Tracy L Young-Pearse
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, 60 Fenwood Rd, Boston, MA, 02115, USA.
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19
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Balu D, Valencia-Olvera AC, Nguyen A, Patnam M, York J, Peri F, Neumann F, LaDu MJ, Tai LM. A small-molecule TLR4 antagonist reduced neuroinflammation in female E4FAD mice. Alzheimers Res Ther 2023; 15:181. [PMID: 37858252 PMCID: PMC10585767 DOI: 10.1186/s13195-023-01330-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 10/10/2023] [Indexed: 10/21/2023]
Abstract
BACKGROUND APOE genotype is the greatest genetic risk factor for sporadic Alzheimer's disease (AD). APOE4 increases AD risk up to 12-fold compared to APOE3, an effect that is greater in females. Evidence suggests that one-way APOE could modulate AD risk and progression through neuroinflammation. Indeed, APOE4 is associated with higher glial activation and cytokine levels in AD patients and mice. Therefore, identifying pathways that contribute to APOE4-associated neuroinflammation is an important approach for understanding and treating AD. Human and in vivo evidence suggests that TLR4, one of the key receptors involved in the innate immune system, could be involved in APOE-modulated neuroinflammation. Consistent with that idea, we previously demonstrated that the TLR4 antagonist IAXO-101 can reduce LPS- and Aβ-induced cytokine secretion in APOE4 glial cultures. Therefore, the goal of this study was to advance these findings and determine whether IAXO-101 can modulate neuroinflammation, Aβ pathology, and behavior in mice that express APOE4. METHODS We used mice that express five familial AD mutations and human APOE3 (E3FAD) or APOE4 (E4FAD). Female and male E4FAD mice and female E3FAD mice were treated with vehicle or IAXO-101 in two treatment paradigms: prevention from 4 to 6 months of age or reversal from 6 to 7 months of age. Learning and memory were assessed by modified Morris water maze. Aβ deposition, fibrillar amyloid deposition, astrogliosis, and microgliosis were assessed by immunohistochemistry. Soluble levels of Aβ and apoE, insoluble levels of apoE and Aβ, and IL-1β were measured by ELISA. RESULTS IAXO-101 treatment resulted in lower Iba-1 coverage, lower number of reactive microglia, and improved memory in female E4FAD mice in both prevention and reversal paradigms. IAXO-101-treated male E4FAD mice also had lower Iba-1 coverage and reactivity in the RVS paradigm, but there was no effect on behavior. There was also no effect of IAXO-101 treatment on neuroinflammation and behavior in female E3FAD mice. CONCLUSION Our data supports that TLR4 is a potential mechanistic therapeutic target for modulating neuroinflammation and cognition in APOE4 females.
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Affiliation(s)
- Deebika Balu
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Ana C Valencia-Olvera
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Austin Nguyen
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Mehul Patnam
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Jason York
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Francesco Peri
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | | | - Mary Jo LaDu
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Leon M Tai
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, 60612, USA.
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20
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Fan Q, Wu YZ, Jia XX, A R, Liu CM, Zhang WW, Chao ZY, Zhou DH, Wang Y, Chen J, Xiao K, Chen C, Shi Q, Dong XP. Increased Gal-3 Mediates Microglia Activation and Neuroinflammation via the TREM2 Signaling Pathway in Prion Infection. ACS Chem Neurosci 2023; 14:3772-3793. [PMID: 37769016 DOI: 10.1021/acschemneuro.3c00344] [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] [Indexed: 09/30/2023] Open
Abstract
Galectin 3 (Gal-3) is one of the major elements for activating microglia and mediating neuroinflammation in some types of neurodegenerative diseases. However, its role in the pathogenesis of prion disease is seldom addressed. In this study, markedly increased brain Gal-3 was identified in three scrapie-infected rodent models at the terminal stage. The increased Gal-3 was mainly colocalized with the activated microglia. Coincidental with the increased brain Gal-3 in prion-infected animals, the expression of brain trigger receptor expressed in myeloid cell 2 (TREM2), one of the Gal-3 receptors, and some components in the downstream pathway also significantly increased, whereas Toll-like receptor 4 (TLR4), another Gal-3 receptor, and the main components in its downstream signaling were less changed. The increased Gal-3 signals were distributed at the areas with PrPSc deposit but looked not to colocalize directly with PrPSc/PrP signals. Similar changing profiles of Gal-3, the receptors TREM2 and TLR4, as well as the proteins in the downstream pathways were also observed in prion-infected cell line SMB-S15. Removal of PrPSc replication in SMB-S15 cells reversed the upregulation of cellular Gal-3, TREM2, and the relevant proteins. Moreover, we presented data for interactions of Gal-3 with TREM2 and with TLR4 morphologically and molecularly in the cultured cells. Stimulation of prion-infected cells or their normal partner cells with recombinant mouse Gal-3 in vitro induced obvious responses for activation of TREM2 signaling and TLR4 signaling. Our data here strongly indicate that prion infection or PrPSc deposit induces remarkably upregulated brain Gal-3, which is actively involved in the microglia activation and neuroinflammation mainly via TREM2 signaling.
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Affiliation(s)
- Qin Fan
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Yue-Zhang Wu
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Xiao-Xi Jia
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Ruhan A
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Chu-Mou Liu
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Wei-Wei Zhang
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- North China University of Science and Technology, Tangshan 063210 China
| | - Zhi-Yue Chao
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Dong-Hua Zhou
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Yuan Wang
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- North China University of Science and Technology, Tangshan 063210 China
| | - Jia Chen
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Kang Xiao
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Cao Chen
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Qi Shi
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Xiao-Ping Dong
- National Key-Laboratory of Intelligent Tracing and Forecasting for Infectious Disease, NHC Key Laboratory of Medical Virology and Viral Diseases, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan 430071, China
- China Academy of Chinese Medical Sciences, Beijing 100700, China
- Shanghai Institute of Infectious Disease and Biosafety, Shanghai 200032, China
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21
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Sangineto M, Ciarnelli M, Cassano T, Radesco A, Moola A, Bukke VN, Romano A, Villani R, Kanwal H, Capitanio N, Duda L, Avolio C, Serviddio G. Metabolic reprogramming in inflammatory microglia indicates a potential way of targeting inflammation in Alzheimer's disease. Redox Biol 2023; 66:102846. [PMID: 37586250 PMCID: PMC10457454 DOI: 10.1016/j.redox.2023.102846] [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: 07/17/2023] [Accepted: 08/08/2023] [Indexed: 08/18/2023] Open
Abstract
Microglia activation drives the pro-inflammatory activity in the early stages of Alzheimer's disease (AD). However, the mechanistic basis is elusive, and the hypothesis of targeting microglia to prevent AD onset is little explored. Here, we demonstrated that upon LPS exposure, microglia shift towards an energetic phenotype characterised by high glycolysis and high mitochondrial respiration with dysfunction. Although the activity of electron transport chain (ETC) complexes is boosted by LPS, this is mostly devoted to the generation of reactive oxygen species. We showed that by inhibiting succinate dehydrogenase (SDH) with dimethyl malonate (DMM), it is possible to modulate the LPS-induced metabolic rewiring, facilitating an anti-inflammatory phenotype. DMM improves mitochondrial function in a direct way and by reducing LPS-induced mitochondrial biogenesis. Moreover, the block of SDH with DMM inhibits the recruitment of hypoxia inducible-factor 1 α (HIF-1α), which mediates the induction of glycolysis and cytokine expression. Similar bioenergetic alterations were observed in the microglia isolated from AD mice (3xTg-AD), which present high levels of circulating LPS and brain toll-like receptor4 (TLR4). Moreover, this well-established model of AD was used to show a potential effect of SDH inhibition in vivo as DMM administration abrogated brain inflammation and modulated the microglia metabolic alterations of 3xTg-AD mice. The RNA-sequencing analysis from a public dataset confirmed the consistent transcription of genes encoding for ETC subunits in the microglia of AD mice (5xFAD). In conclusion, TLR4 activation promotes metabolic changes and the pro-inflammatory activity in microglia, and SDH might represent a promising therapeutic target to prevent AD development.
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Affiliation(s)
- Moris Sangineto
- C.U.R.E. (University Center for Liver Disease Research and Treatment), Liver Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy.
| | - Martina Ciarnelli
- C.U.R.E. (University Center for Liver Disease Research and Treatment), Liver Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Tommaso Cassano
- Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Antonio Radesco
- Istituto Oncologico "Giovanni Paolo II", I.R.C.S.S. of Bari, Laboratory of Haematological Diagnostics and Cellular Therapy, Bari, Italy
| | - Archana Moola
- C.U.R.E. (University Center for Liver Disease Research and Treatment), Liver Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Vidyasagar Naik Bukke
- C.U.R.E. (University Center for Liver Disease Research and Treatment), Liver Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Antonino Romano
- C.U.R.E. (University Center for Liver Disease Research and Treatment), Liver Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Rosanna Villani
- C.U.R.E. (University Center for Liver Disease Research and Treatment), Liver Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Hina Kanwal
- C.U.R.E. (University Center for Liver Disease Research and Treatment), Liver Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Nazzareno Capitanio
- Biochemistry Unit, Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | - Loren Duda
- Pathology Unit, Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | - Carlo Avolio
- Neurology Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Gaetano Serviddio
- C.U.R.E. (University Center for Liver Disease Research and Treatment), Liver Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
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22
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Weaver DF. Druggable targets for the immunopathy of Alzheimer's disease. RSC Med Chem 2023; 14:1645-1661. [PMID: 37731705 PMCID: PMC10507808 DOI: 10.1039/d3md00096f] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 06/21/2023] [Indexed: 09/22/2023] Open
Abstract
Alzheimer's disease (AD) is one of the leading threats to the health and socioeconomic well-being of humankind. Though research to develop disease modifying therapies for AD has traditionally focussed on the misfolding and aggregation of proteins, this approach has failed to yield a definitively curative agent. Accordingly, the search for additional or alternative approaches is a medicinal chemistry priority. Dysfunction of the brain's neuroimmune-neuroinflammation axis has emerged as a leading contender. Neuroimmunity however is mechanistically complex, rendering the recognition of candidate receptors a challenging task. Herein, a review of the role of neuroimmunity in the biomolecular pathogenesis of AD is presented with the identification of a 'druggable dozen' targets; in turn, each identified target represents one or more discrete receptors centred on a common biochemical mechanism. The druggable dozen is composed of both cellular and molecular messenger targets, with a 'targetable ten' microglial targets as well as two cytokine-based targets. For each target, the underlying molecular basis, with a consideration of strengths and weaknesses, is considered.
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Affiliation(s)
- Donald F Weaver
- Krembil Research Institute, University Health Network, Department of Chemistry, University of Toronto 60 Leonard Avenue Toronto ON M5T 0S8 Canada
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23
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Lana D, Magni G, Landucci E, Wenk GL, Pellegrini-Giampietro DE, Giovannini MG. Phenomic Microglia Diversity as a Druggable Target in the Hippocampus in Neurodegenerative Diseases. Int J Mol Sci 2023; 24:13668. [PMID: 37761971 PMCID: PMC10531074 DOI: 10.3390/ijms241813668] [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: 07/27/2023] [Revised: 08/31/2023] [Accepted: 09/02/2023] [Indexed: 09/29/2023] Open
Abstract
Phenomics, the complexity of microglia phenotypes and their related functions compels the continuous study of microglia in disease animal models to find druggable targets for neurodegenerative disorders. Activation of microglia was long considered detrimental for neuron survival, but more recently it has become apparent that the real scenario of microglia morphofunctional diversity is far more complex. In this review, we discuss the recent literature on the alterations in microglia phenomics in the hippocampus of animal models of normal brain aging, acute neuroinflammation, ischemia, and neurodegenerative disorders, such as AD. Microglia undergo phenomic changes consisting of transcriptional, functional, and morphological changes that transform them into cells with different properties and functions. The classical subdivision of microglia into M1 and M2, two different, all-or-nothing states is too simplistic, and does not correspond to the variety of phenotypes recently discovered in the brain. We will discuss the phenomic modifications of microglia focusing not only on the differences in microglia reactivity in the diverse models of neurodegenerative disorders, but also among different areas of the brain. For instance, in contiguous and highly interconnected regions of the rat hippocampus, microglia show a differential, finely regulated, and region-specific reactivity, demonstrating that microglia responses are not uniform, but vary significantly from area to area in response to insults. It is of great interest to verify whether the differences in microglia reactivity may explain the differential susceptibility of different brain areas to insults, and particularly the higher sensitivity of CA1 pyramidal neurons to inflammatory stimuli. Understanding the spatiotemporal heterogeneity of microglia phenomics in health and disease is of paramount importance to find new druggable targets for the development of novel microglia-targeted therapies in different CNS disorders. This will allow interventions in three different ways: (i) by suppressing the pro-inflammatory properties of microglia to limit the deleterious effect of their activation; (ii) by modulating microglia phenotypic change to favor anti-inflammatory properties; (iii) by influencing microglia priming early in the disease process.
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Affiliation(s)
- Daniele Lana
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy; (E.L.); (D.E.P.-G.); (M.G.G.)
| | - Giada Magni
- Institute of Applied Physics “Nello Carrara”, National Research Council (IFAC-CNR), Via Madonna del Piano 10, 50019 Florence, Italy;
| | - Elisa Landucci
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy; (E.L.); (D.E.P.-G.); (M.G.G.)
| | - Gary L. Wenk
- Department of Psychology, The Ohio State University, Columbus, OH 43210, USA;
| | - Domenico Edoardo Pellegrini-Giampietro
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy; (E.L.); (D.E.P.-G.); (M.G.G.)
| | - Maria Grazia Giovannini
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy; (E.L.); (D.E.P.-G.); (M.G.G.)
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24
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Atef MM, Mostafa YM, Ahmed AAM, El-Sayed NM. Simvastatin attenuates aluminium chloride-induced neurobehavioral impairments through activation of TGF-β1/ SMAD2 and GSK3β/β-catenin signalling pathways. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2023; 102:104220. [PMID: 37454825 DOI: 10.1016/j.etap.2023.104220] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 06/19/2023] [Accepted: 07/10/2023] [Indexed: 07/18/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease characterised by the presence of β-amyloid plaques and acetylcholine depletion leading to neurobehavioral defects. AD was contributed also with downregulation of TGF-β1/SMAD2 and GSK3β/β-catenin pathways. Simvastatin (SMV) improved memory function experimentally and clinically. Hence, this study aimed to investigate the mechanistic role of SMV against aluminium chloride (AlCl3) induced neurobehavioral impairments. AD was induced by AlCl3 (50 mg/kg) for 6 weeks. Mice received Simvastatin (10 or 20 mg/kg) or Donepezil (3 mg/kg) for 6 weeks after that the histopathological, immunohistochemical and biochemical test were examined. Treatment with SMV improved the memory deterioration induced by AlCl3 with significant recovery of the histopathological changes. This was concomitant with the decrease of AChE and Aβ (1-42). SMV provides its neuroprotective effect through upregulating the protein expression of β-catenin, TGF-β1 and downregulating the expression of GSK3β, TLR4 and p-SMAD2.
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Affiliation(s)
| | - Yasser M Mostafa
- Department of Pharmacology & Toxicology, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt; Department of Pharmacology & Toxicology, Faculty of Pharmacy, Badr University in Cairo, Egypt
| | - Amal A M Ahmed
- Department of Cytology & Histology, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, Egypt
| | - Norhan M El-Sayed
- Department of Pharmacology & Toxicology, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt.
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25
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Yadav H, Shirumalla RK. Emerging trends in IRAK-4 kinase research. Mol Biol Rep 2023; 50:7825-7837. [PMID: 37490192 DOI: 10.1007/s11033-023-08438-w] [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: 05/27/2022] [Accepted: 04/06/2023] [Indexed: 07/26/2023]
Abstract
The IRAK-4 kinase lies at a critical signaling node that drives cancer cell survival through multiple mechanisms, activation, and translocation of NF-κB mediated inflammatory responses and innate immune signaling through regulation of interferon-α/β receptor (IFNα/β). Inhibition, of IRAK-4, has consequently drawn a lot of attention in recent years to address indications ranging from oncology to autoimmune disorders to neurodegeneration, etc. However, the key stumbling block in targeting IRAK-4 is that despite the inhibition of the kinase activity using an inhibitor the target remains effective, reducing the potential of an inhibitor. This is due to the "scaffolding effect" because of which although regulation of downstream processes by IRAK-4 has been primarily linked with kinase function; however, still, various reports have suggested that IRAK-4 has a non-kinase function in a variety of cell types. This is attributed to the myddosome complex formed by IRAK-4 with myd88, IRAK-2, and IRAK-1 which by itself can cause the activation of downstream effector TRAF6 despite inhibition of the kinase domain of IRAK-4. With this challenge, several groups initiated the development of targeting protein degraders of IRAK-4 using Proteolysis-Targeting Chimeras (PROTACs) technology to completely remove the IRAK-4 from the cellular milieu. In this review, we will capture all these developments and the evolving science around this target.
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Affiliation(s)
- Himanshu Yadav
- SGT College of Pharmacy, SGT University, Budhera, Gurugram, Haryana, 122505, India
| | - Raj Kumar Shirumalla
- SGT College of Pharmacy, SGT University, Budhera, Gurugram, Haryana, 122505, India.
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26
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Zhu Z, Zhang L, Elsherbini A, Crivelli SM, Tripathi P, Harper C, Quadri Z, Spassieva SD, Bieberich E. The S1P receptor 1 antagonist Ponesimod reduces TLR4-induced neuroinflammation and increases Aβ clearance in 5XFAD mice. EBioMedicine 2023; 94:104713. [PMID: 37480622 PMCID: PMC10393615 DOI: 10.1016/j.ebiom.2023.104713] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 06/29/2023] [Accepted: 06/29/2023] [Indexed: 07/24/2023] Open
Abstract
BACKGROUND Previously, we showed that the sphingosine-1-phosphate (S1P) transporter spinster 2 (Spns2) mediates activation of microglia in response to amyloid β peptide (Aβ). Here, we investigated if Ponesimod, a functional S1P receptor 1 (S1PR1) antagonist, prevents Aβ-induced activation of glial cells and Alzheimer's disease (AD) pathology. METHODS We used primary cultures of glial cells and the 5XFAD mouse model to determine the effect of Aβ and Ponesimod on glial activation, Aβ phagocytosis, cytokine levels and pro-inflammatory signaling pathways, AD pathology, and cognitive performance. FINDINGS Aβ42 increased the levels of TLR4 and S1PR1, leading to their complex formation. Ponesimod prevented the increase in TLR4 and S1PR1 levels, as well as the formation of their complex. It also reduced the activation of the pro-inflammatory Stat1 and p38 MAPK signaling pathways, while activating the anti-inflammatory Stat6 pathway. This was consistent with increased phagocytosis of Aβ42 in primary cultured microglia. In 5XFAD mice, Ponesimod decreased the levels of TNF-α and CXCL10, which activate TLR4 and Stat1. It also increased the level of IL-33, an anti-inflammatory cytokine that promotes Aβ42 phagocytosis by microglia. As a result of these changes, Ponesimod decreased the number of Iba-1+ microglia and GFAP+ astrocytes, and the size and number of amyloid plaques, while improving spatial memory as measured in a Y-maze test. INTERPRETATION Ponesimod targeting S1PR1 is a promising therapeutic approach to reprogram microglia, reduce neuroinflammation, and increase Aβ clearance in AD. FUNDING NIHR01AG064234, RF1AG078338, R21AG078601, VAI01BX003643.
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Affiliation(s)
- Zhihui Zhu
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, United States
| | - Liping Zhang
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, United States
| | - Ahmed Elsherbini
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, United States
| | - Simone M Crivelli
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, United States
| | - Priyanka Tripathi
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, United States
| | - Carmen Harper
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, United States
| | - Zainuddin Quadri
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, United States
| | - Stefka D Spassieva
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, United States
| | - Erhard Bieberich
- Department of Physiology, University of Kentucky College of Medicine, Lexington, KY 40536, United States; Veterans Affairs Medical Center, Lexington, KY 40502, United States.
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27
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Choi SB, Kwon S, Kim JH, Ahn NH, Lee JH, Yang SH. The Molecular Mechanisms of Neuroinflammation in Alzheimer's Disease, the Consequence of Neural Cell Death. Int J Mol Sci 2023; 24:11757. [PMID: 37511515 PMCID: PMC10380735 DOI: 10.3390/ijms241411757] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/17/2023] [Accepted: 07/20/2023] [Indexed: 07/30/2023] Open
Abstract
Alzheimer's disease (AD) is accompanied by neural cell loss and memory deficit. Neural cell death, occurring via apoptosis and autophagy, is widely observed in the AD brain in addition to neuroinflammation mediated by necroptosis and the NLRP3 inflammasome. Neurotoxicity induced by amyloid-beta (Aβ) and tau aggregates leads to excessive neural cell death and neuroinflammation in the AD brain. During AD progression, uncontrolled neural cell death results in the dysregulation of cellular activity and synaptic function. Apoptosis mediated by pro-apoptotic caspases, autophagy regulated by autophagy-related proteins, and necroptosis controlled by the RIPK/MLKL axis are representative of neural cell death occurred during AD. Necroptosis causes the release of cellular components, contributing to the pro-inflammatory environment in the AD brain. Inordinately high levels of neural cell death and pro-inflammatory events lead to the production of pro-inflammatory cytokines and feed-forward hyper neuroinflammation. Thus, neural cell death and neuroinflammation cause synaptic dysfunction and memory deficits in the AD brain. In this review, we briefly introduce the mechanisms of neural cell death and neuroinflammation observed in the AD brain. Combined with a typical strategy for targeting Aβ and tau, regulation of neural cell death and neuroinflammation may be effective for the amelioration of AD pathologies.
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Affiliation(s)
- Su-Bin Choi
- Department of Biomedical Engineering, College of Life Science and Biotechnology, Dongguk University, Seoul 04620, Republic of Korea
| | - Sehee Kwon
- Department of Biomedical Engineering, College of Life Science and Biotechnology, Dongguk University, Seoul 04620, Republic of Korea
| | - Ji-Hye Kim
- Department of Biomedical Engineering, College of Life Science and Biotechnology, Dongguk University, Seoul 04620, Republic of Korea
| | - Na-Hyun Ahn
- Department of Biomedical Engineering, College of Life Science and Biotechnology, Dongguk University, Seoul 04620, Republic of Korea
| | - Joo-Hee Lee
- Department of Biomedical Engineering, College of Life Science and Biotechnology, Dongguk University, Seoul 04620, Republic of Korea
| | - Seung-Hoon Yang
- Department of Biomedical Engineering, College of Life Science and Biotechnology, Dongguk University, Seoul 04620, Republic of Korea
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Ibrahim WW, Skalicka-Woźniak K, Budzyńska B, El Sayed NS. NLRP3 inflammasome inhibition and M1-to-M2 microglial polarization shifting via scoparone-inhibited TLR4 axis in ovariectomy/D-galactose Alzheimer's disease rat model. Int Immunopharmacol 2023; 119:110239. [PMID: 37137264 DOI: 10.1016/j.intimp.2023.110239] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/15/2023] [Accepted: 04/22/2023] [Indexed: 05/05/2023]
Abstract
Neuroinflammation mediated by microglia activation is a critical contributor to Alzheimer's disease (AD) pathogenesis. Dysregulated microglia polarization in terms of M1 overactivation with M2 inhibition is involved in AD pathological damage. Scoparone (SCO), a coumarin derivative, displays several beneficial pharmacological effects including anti-inflammatory and anti-apoptotic properties, however, its neurological effect in AD is still elusive. This study investigated the neuroprotective potential of SCO in AD animal model focusing on determining its effect on M1/M2 microglia polarization and exploring the plausible mechanism involved via investigating its modulatory role on TLR4/MyD88/NF-κB and NLRP3 inflammasome. Sixty female Wistar rats were randomly allocated into four groups. Two groups were sham-operated and treated or untreated with SCO, and the other two groups were subjected to bilateral ovariectomy (OVX) and received D-galactose (D-Gal; 150 mg/kg/day, i.p) alone or with SCO (12.5 mg/kg/day, i.p) for 6 weeks. SCO improved memory functions of OVX/D-Gal rats in the Morris water maze and novel object recognition tests. It also reduced the hippocampal burden of amyloid-β42 and p-Tau, additionally, the hippocampal histopathological architecture was prominently preserved. SCO inhibited the gene expression of TLR4, MyD88, TRAF-6, and TAK-1, additionally, p-JNK and NF-κBp65 levels were significantly curbed. This was associated with repression of NLRP3 inflammasome along with M1-to-M2 microglia polarization shifting as exemplified by mitigating pro-inflammatory M1 marker (CD86) and elevating M2 neuroprotective marker (CD163). Therefore, SCO could promote microglia transition towards M2 through switching off TLR4/MyD88/TRAF-6/TAK-1/NF-κB axis and inhibiting NLRP3 pathway, with consequent mitigation of neuroinflammation and neurodegeneration in OVX/D-Gal AD model.
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Affiliation(s)
- Weam W Ibrahim
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Cairo, Egypt.
| | | | - Barbara Budzyńska
- Independent Laboratory of Behavioral Studies, Medical University of Lublin, Lublin, Poland
| | - Nesrine S El Sayed
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
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Huffels CFM, Middeldorp J, Hol EM. Aß Pathology and Neuron-Glia Interactions: A Synaptocentric View. Neurochem Res 2023; 48:1026-1046. [PMID: 35976488 PMCID: PMC10030451 DOI: 10.1007/s11064-022-03699-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 06/30/2022] [Accepted: 07/15/2022] [Indexed: 10/15/2022]
Abstract
Alzheimer's disease (AD) causes the majority of dementia cases worldwide. Early pathological hallmarks include the accumulation of amyloid-ß (Aß) and activation of both astrocytes and microglia. Neurons form the building blocks of the central nervous system, and astrocytes and microglia provide essential input for its healthy functioning. Their function integrates at the level of the synapse, which is therefore sometimes referred to as the "quad-partite synapse". Increasing evidence puts AD forward as a disease of the synapse, where pre- and postsynaptic processes, as well as astrocyte and microglia functioning progressively deteriorate. Here, we aim to review the current knowledge on how Aß accumulation functionally affects the individual components of the quad-partite synapse. We highlight a selection of processes that are essential to the healthy functioning of the neuronal synapse, including presynaptic neurotransmitter release and postsynaptic receptor functioning. We further discuss how Aß affects the astrocyte's capacity to recycle neurotransmitters, release gliotransmitters, and maintain ion homeostasis. We additionally review literature on how Aß changes the immunoprotective function of microglia during AD progression and conclude by summarizing our main findings and highlighting the challenges in current studies, as well as the need for further research.
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Affiliation(s)
- Christiaan F M Huffels
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Jinte Middeldorp
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
- Department of Neurobiology & Aging, Biomedical Primate Research Centre, Rijswijk, The Netherlands
| | - Elly M Hol
- Department of Translational Neuroscience, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands.
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Dabi YT, Ajagbe AO, Degechisa ST. Toll-like receptors in pathogenesis of neurodegenerative diseases and their therapeutic potential. Immun Inflamm Dis 2023; 11:e839. [PMID: 37102648 PMCID: PMC10116887 DOI: 10.1002/iid3.839] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/17/2023] [Accepted: 03/29/2023] [Indexed: 04/28/2023] Open
Abstract
Toll-like receptors (TLRs) are a family of pattern-recognition receptors triggered by pathogen-derived and tissue-damage-related ligands. TLRs were previously believed to only be expressed in immune cells. However, it is now confirmed that they are ubiquitously expressed in cells within the body including neurons, astrocytes, and microglia of the central nervous system (CNS). Activation of TLRs is capable of inducing immunologic and inflammatory responses to injury or infection of CNS. This response is self-limiting that usually resolves once the infection has been eradicated or the tissue damage has been repaired. However, the persistence of inflammation-inducing insults or a failure in normal resolution mechanisms may result in overwhelming inflammation which may induce neurodegeneration. This implies that TLRs may play a role in mediating the link between inflammation and neurodegenerative diseases namely Alzheimer's disease, Parkinson's disease, Huntington's disease, stroke, and amyotrophic lateral sclerosis. So, new therapeutic approaches that specifically target TLRs may be developed by better understanding TLR expression mechanisms in the CNS and their connections to particular neurodegenerative disorders. Therefore, this review paper discussed the role of TLRs in neurodegenerative diseases.
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Affiliation(s)
- Yosef Tsegaye Dabi
- Department of Medical Laboratory Science, Institute of Health SciencesWollega UniversityNekemteEthiopia
| | - Abayomi O. Ajagbe
- Department of Anatomy, College of Health Sciences, Faculty of Basic Medical SciencesNile University of NigeriaAbujaNigeria
| | - Sisay T. Degechisa
- Department of Medical Biochemistry, School of Medicine, College of Health SciencesAddis Ababa UniversityAddis AbabaEthiopia
- Department of Medical Laboratory Sciences, College of Medicine and Health SciencesArba Minch UniversityArba MinchEthiopia
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31
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Decandia D, Gelfo F, Landolfo E, Balsamo F, Petrosini L, Cutuli D. Dietary Protection against Cognitive Impairment, Neuroinflammation and Oxidative Stress in Alzheimer's Disease Animal Models of Lipopolysaccharide-Induced Inflammation. Int J Mol Sci 2023; 24:ijms24065921. [PMID: 36982996 PMCID: PMC10051444 DOI: 10.3390/ijms24065921] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 03/14/2023] [Accepted: 03/16/2023] [Indexed: 03/30/2023] Open
Abstract
Alzheimer's disease (AD) is a rapidly growing epidemic with a heavy social and economic burden. Evidence suggests that systemic inflammation, dysregulation of the immune response and the resulting neuroinflammation and neurodegeneration play a significant role in AD pathogenesis. Currently, given that there is no fully convincing cure for AD, the interest in lifestyle factors (such as diet), which potentially delay onset and reduce the severity of symptoms, is increasing. This review is aimed at summarizing the effects of dietary supplementation on cognitive decline, neuroinflammation and oxidative stress in AD-like animal models with a focus on neuroinflammation induced by lipopolysaccharide (LPS) injection, which mimics systemic inflammation in animals. The compounds reviewed include curcumin, krill oil, chicoric acid, plasmalogens, lycopene, tryptophan-related dipeptides, hesperetin and selenium peptides. Despite the heterogeneity of these compounds, there is a strong consensus on their counteracting action on LPS-induced cognitive deficits and neuroinflammatory responses in rodents by modulating cell-signaling processes, such as the NF-κB pathway. Overall, dietary interventions could represent an important resource to oppose AD due to their influence in neuroprotection and immune regulation.
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Affiliation(s)
- Davide Decandia
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
- Department of Psychology, Sapienza University of Rome, Via dei Marsi 78, 00185 Rome, Italy
| | - Francesca Gelfo
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
- Department of Human Sciences, Guglielmo Marconi University, Via Plinio 44, 00193 Rome, Italy
| | - Eugenia Landolfo
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
| | - Francesca Balsamo
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
- Department of Human Sciences, Guglielmo Marconi University, Via Plinio 44, 00193 Rome, Italy
| | - Laura Petrosini
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
| | - Debora Cutuli
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
- Department of Psychology, Sapienza University of Rome, Via dei Marsi 78, 00185 Rome, Italy
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32
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Xu J, Farsad HL, Hou Y, Barclay K, Lopez BA, Yamada S, Saliu IO, Shi Y, Knight WC, Bateman RJ, Benzinger TLS, Yi JJ, Li Q, Wang T, Perlmutter JS, Morris JC, Zhao G. Human striatal glia differentially contribute to AD- and PD-specific neurodegeneration. NATURE AGING 2023; 3:346-365. [PMID: 36993867 PMCID: PMC10046522 DOI: 10.1038/s43587-023-00363-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 01/09/2023] [Indexed: 02/11/2023]
Abstract
The commonalities and differences in cell-type-specific pathways that lead to Alzheimer disease (AD) and Parkinson disease (PD) remain unknown. Here, we performed a single-nucleus transcriptome comparison of control, AD and PD striata. We describe three astrocyte subpopulations shared across different brain regions and evolutionarily conserved between humans and mice. We reveal common features between AD and PD astrocytes and regional differences that contribute toward amyloid pathology and neurodegeneration. In contrast, we found that transcriptomic changes in microglia are largely unique to each disorder. Our analysis identified a population of activated microglia that shared molecular signatures with murine disease-associated microglia (DAM) as well as disease-associated and regional differences in microglia transcriptomic changes linking microglia to disease-specific amyloid pathology, tauopathy and neuronal death. Finally, we delineate undescribed subpopulations of medium spiny neurons (MSNs) in the striatum and provide neuronal transcriptomic profiles suggesting disease-specific changes and selective neuronal vulnerability.
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Affiliation(s)
- Jinbin Xu
- The Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Huifangjie L. Farsad
- The Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Yiran Hou
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
- Present address: Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA
| | - Kia Barclay
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
| | - Ben Anthony Lopez
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
- MD-PhD in Molecular Medicine Program, College of Medicine, University of the Philippines Manila, Manila, Philippines
| | - Shinnosuke Yamada
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Yiming Shi
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
| | - William C. Knight
- The Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Randall J. Bateman
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Tammie L. S. Benzinger
- The Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Jason J. Yi
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
| | - Qingyun Li
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
| | - Ting Wang
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Joel S. Perlmutter
- The Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - John C. Morris
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Guoyan Zhao
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, USA
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
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33
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Li Z, Chen A, Wan H, Gao X, Li C, Xiong L, Liang H. Immunohistochemical Localization of MD2, a Co-Receptor of TLR4, in the Adult Mouse Brain. ACS Chem Neurosci 2023; 14:400-417. [PMID: 36657737 PMCID: PMC9897217 DOI: 10.1021/acschemneuro.2c00540] [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: 09/07/2022] [Accepted: 01/04/2023] [Indexed: 01/21/2023] Open
Abstract
Myeloid differentiation factor 2 (MD2) is a co-receptor of a classical proinflammatory protein TLR4 whose activation leads to neuroinflammation. It is widely accepted that TLR4 is expressed on the cell surface of microglia and astrocytes, and MD2 is expected to be expressed by these cells as well. However, our previous study showed that neurons from certain nuclei also expressed MD2. Whether MD2 is expressed by other brain nuclei is still unknown. It is the aim of the present study to map the distribution of MD2-positive cells in the adult mouse brain. Immunohistochemical staining against MD2 was completed to localize MD2-positive cells in the mouse brain by comparing the location of positive cells with the mouse brain atlas. MD2-positive cells were found in the majority of mouse brain nuclei with clusters of cells in the olfactory bulb, cortices, the red nucleus, and cranial nuclei. Subcortical nuclei had heterogeneous staining of MD2 with more prominent cells in the basolateral and the central amygdaloid nuclei. The ventral pallidum and the diagonal bands had positive cells with similar density and shape. Prominent cells were present in thalamic nuclei which were nearly homogeneous and in reticular formation of the brainstem where cells were dispersed with similar density. The hypothalamus had fewer outstanding cells compared with the thalamus. The red nucleus, the substantia nigra, and the ventral tegmental area in the pretectum had outstanding cells. Motor cranial nuclei also had outstanding MD2-positive cells, whereas raphe, sensory cranial, and deep cerebellar nuclei had MD2-positive cells with moderate density. The presence of MD2 in these nuclei may suggest the involvement of MD2 in their corresponding physiological functions.
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Affiliation(s)
- Zhen Li
- Clinical
Research Center for Anesthesiology and Perioperative Medicine, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Translational
Research Institute of Brain and Brain-Like Intelligence, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Department
of Anesthesiology and Perioperative Medicine, Shanghai Fourth People’s
Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Shanghai
Key Laboratory of Anesthesiology and Brain Functional Modulation, Shanghai 200434, China
| | - Aiwen Chen
- Clinical
Research Center for Anesthesiology and Perioperative Medicine, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Translational
Research Institute of Brain and Brain-Like Intelligence, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Department
of Anesthesiology and Perioperative Medicine, Shanghai Fourth People’s
Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Shanghai
Key Laboratory of Anesthesiology and Brain Functional Modulation, Shanghai 200434, China
| | - Hanxi Wan
- Clinical
Research Center for Anesthesiology and Perioperative Medicine, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Translational
Research Institute of Brain and Brain-Like Intelligence, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Department
of Anesthesiology and Perioperative Medicine, Shanghai Fourth People’s
Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Shanghai
Key Laboratory of Anesthesiology and Brain Functional Modulation, Shanghai 200434, China
| | - Xiaofei Gao
- Clinical
Research Center for Anesthesiology and Perioperative Medicine, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Translational
Research Institute of Brain and Brain-Like Intelligence, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Department
of Anesthesiology and Perioperative Medicine, Shanghai Fourth People’s
Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Shanghai
Key Laboratory of Anesthesiology and Brain Functional Modulation, Shanghai 200434, China
| | - Chunguang Li
- NICM
Health Research Institute, Western Sydney
University, Penrith, New South Wales 2751, Australia
| | - Lize Xiong
- Clinical
Research Center for Anesthesiology and Perioperative Medicine, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Translational
Research Institute of Brain and Brain-Like Intelligence, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Department
of Anesthesiology and Perioperative Medicine, Shanghai Fourth People’s
Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Shanghai
Key Laboratory of Anesthesiology and Brain Functional Modulation, Shanghai 200434, China
| | - Huazheng Liang
- Clinical
Research Center for Anesthesiology and Perioperative Medicine, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Translational
Research Institute of Brain and Brain-Like Intelligence, Shanghai
Fourth People’s Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Department
of Anesthesiology and Perioperative Medicine, Shanghai Fourth People’s
Hospital, School of Medicine, Tongji University, Shanghai 200434, China
- Shanghai
Key Laboratory of Anesthesiology and Brain Functional Modulation, Shanghai 200434, China
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34
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Ayyubova G. TREM2 signalling as a multifaceted player in brain homoeostasis and a potential target for Alzheimer's disease treatment. Eur J Neurosci 2023; 57:718-733. [PMID: 36637116 DOI: 10.1111/ejn.15914] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 12/27/2022] [Accepted: 01/10/2023] [Indexed: 01/14/2023]
Abstract
Triggering receptor expressed on myeloid cells-2 (TREM2) has crucial roles in microglial physiology, differentiation, metabolism and survival. Genome-wide association studies (GWAS) show that genetic mutations of the TREM2 increase the risk of late-onset Alzheimer's disease (AD) by two to four times, disrupting the microglial function in reducing the progression of the disease. Accumulating data show that TREM2 function in AD is related primarily to the clearance of soluble and insoluble amyloid beta (Aβ42) aggregates from the brain. TREM2 also ameliorates the pathological effects of activated microglia on neuronal tau pathology, demonstrating its protective anti-inflammatory effects. However, since the excessive activation of TREM2 signalling can inhibit pro-inflammatory reactions and suppress the role of microglia in immune surveillance, at the late stages of the disease, it might promote immune tolerance, which is detrimental. The contradictory effects of TREM2 mutations on brain amyloidopathy and tauopathy in multiple mouse models, as well as studies revealing various effects of TREM2 overexpression, complicate the understanding of the role that TREM2 plays in AD aetiopathogenesis. In this review, we summarize the latest developments regarding the significance of TREM2 signalling in the stability of microglial pro- and anti-inflammatory activations and propose the mechanisms that should be targeted in the future to treat AD.
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Affiliation(s)
- Gunel Ayyubova
- Department of Cytology, Embryology and Histology, Azerbaijan Medical University, Baku, Azerbaijan
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35
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Qin J, Ma Z, Chen X, Shu S. Microglia activation in central nervous system disorders: A review of recent mechanistic investigations and development efforts. Front Neurol 2023; 14:1103416. [PMID: 36959826 PMCID: PMC10027711 DOI: 10.3389/fneur.2023.1103416] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 02/13/2023] [Indexed: 03/09/2023] Open
Abstract
Microglia are the principal resident immune cells in the central nervous system (CNS) and play important roles in the development of CNS disorders. In recent years, there have been significant developments in our understanding of microglia, and we now have greater insight into the temporal and spatial patterns of microglia activation in a variety of CNS disorders, as well as the interactions between microglia and neurons. A variety of signaling pathways have been implicated. However, to date, all published clinical trials have failed to demonstrate efficacy over placebo. This review summarizes the results of recent important studies and attempts to provide a mechanistic view of microglia activation, inflammation, tissue repair, and CNS disorders.
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36
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Das TK, Ganesh BP. Interlink between the gut microbiota and inflammation in the context of oxidative stress in Alzheimer's disease progression. Gut Microbes 2023; 15:2206504. [PMID: 37127846 PMCID: PMC10153019 DOI: 10.1080/19490976.2023.2206504] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/03/2023] Open
Abstract
The microbiota-gut-brain axis is an important pathway of communication and may dynamically contribute to Alzheimer's disease (AD) pathogenesis. Pathological commensal gut microbiota alterations, termed as dysbiosis, can influence intestinal permeability and break the blood-brain barrier which may trigger AD pathogenesis via redox signaling, neuronal, immune, and metabolic pathways. Dysbiosis increases the oxidative stress. Oxidants affect the innate immune system through recognizing microbial-derived pathogens by Toll-like receptors and initiating the inflammatory process. Most of the gut microbiome research work highlights the relationship between the gut microbiota and AD, but the contributory connection between precise bacteria and brain dysfunction in AD pathology cannot be fully demonstrated. Here, we summarize the current information of the fundamental connections between oxidative stress, inflammation, and gut dysbiosis in AD. This review emphasizes on the involvement of gut microbiota in the regulation of oxidative stress, inflammation, immune responses including central and peripheral cross-talk. It provides insights for novel preventative and therapeutic approaches in AD.
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Affiliation(s)
- Tushar K Das
- Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Bhanu P Ganesh
- Department of Neurology, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA
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37
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Kwon OY, Lee SH. Ishige okamurae Attenuates Neuroinflammation and Cognitive Deficits in Mice Intracerebroventricularly Injected with LPS via Regulating TLR-4/MyD88-Dependent Pathways. Antioxidants (Basel) 2022; 12:antiox12010078. [PMID: 36670940 PMCID: PMC9854571 DOI: 10.3390/antiox12010078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 12/22/2022] [Accepted: 12/26/2022] [Indexed: 12/31/2022] Open
Abstract
Neuroinflammation is one of the critical causes of neuronal loss and cognitive impairment. We aimed to evaluate the anti-neuroinflammatory properties of Ishige okamuae using mice intracerebroventricularly injected with lipopolysaccharides (LPS) and LPS-treated C6 glioma cells. We found that the short- and long-term memory deficits of LPS-injected mice were improved by oral administration of Ishige okamurae extracts (IOE). LPS-induced neuronal loss, increase in amyloid-β plaque, and expression of COX-2 and iNOS were restored by IOE. In addition, LPS-induced activation of Toll-like receptor-4 (TLR-4) and its downstream molecules, such as MyD88, NFκB, and mitogen-activated protein kinases (MAPKs), were significantly attenuated in the brains of mice fed with IOE. We found that pretreatment of IOE to C6 glioma cells ameliorated LPS-induced expression of TLR-4 and its inflammatory cascades, such as MyD88 expression, reactive oxygen species production, MAPKs phosphorylation, and NFκB phosphorylation with consequent downregulation of COX-2, iNOS, proinflammatory cytokines, and nitric oxide expression. Furthermore, IOE (0.2 µg/mL) was found to have equivalent efficacy with 10 μM of MyD88 inhibitor in preventing LPS-induced inflammatory responses in C6 glioma cells. Taken together, these results strongly suggest that IOE could be developed as a promising anti-neuroinflammatory agent which is able to control the TLR-4/MyD88-dependent signaling pathways.
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38
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Elbandy M. Anti-Inflammatory Effects of Marine Bioactive Compounds and Their Potential as Functional Food Ingredients in the Prevention and Treatment of Neuroinflammatory Disorders. MOLECULES (BASEL, SWITZERLAND) 2022; 28:molecules28010002. [PMID: 36615197 PMCID: PMC9822486 DOI: 10.3390/molecules28010002] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022]
Abstract
Functional foods include enhanced, enriched, fortified, or whole foods that impart health benefits beyond their nutritional value, particularly when consumed as part of a varied diet on a regular basis at effective levels. Marine sources can serve as the sources of various healthy foods and numerous functional food ingredients with biological effects can be derived from these sources. Microalgae, macroalgae, crustaceans, fungi, bacteria fish, and fish by-products are the most common marine sources that can provide many potential functional food ingredients including phenolic compounds, proteins and peptides, and polysaccharides. Neuroinflammation is closely linked with the initiation and progression of various neurodegenerative diseases, including Alzheimer's disease, Huntington's disease, and Parkinson's disease. Activation of astrocytes and microglia is a defense mechanism of the brain to counter damaged tissues and detrimental pathogens, wherein their chronic activation triggers neuroinflammation that can further exacerbate or induce neurodegeneration. Currently, available therapeutic agents only provide symptomatic relief from these disorders and no therapies are available to stop or slow down the advancement of neurodegeneration. Thereffore, natural compounds that can exert a protective effect against these disorders have therapeutic potential. Numerous chemical compounds, including bioactive peptides, fatty acids, pigments, alkaloids, and polysaccharides, have already been isolated from marine sources that show anti-inflammatory properties, which can be effective in the treatment and prevention of neuroinflammatory disorders. The anti-inflammatory potential of marine-derived compounds as functional food ingredients in the prevention and treatment of neurological disorders is covered in this review.
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Affiliation(s)
- Mohamed Elbandy
- Department of Clinical Nutrition, College of Applied Medical Science, Jazan University, Jazan 45142, Saudi Arabia
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39
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Neuroprotective Effects of Nicotinamide against MPTP-Induced Parkinson's Disease in Mice: Impact on Oxidative Stress, Neuroinflammation, Nrf2/HO-1 and TLR4 Signaling Pathways. Biomedicines 2022; 10:biomedicines10112929. [PMID: 36428497 PMCID: PMC9687839 DOI: 10.3390/biomedicines10112929] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/04/2022] [Accepted: 11/11/2022] [Indexed: 11/16/2022] Open
Abstract
Nicotinamide (NAM) is the amide form of niacin and an important precursor of nicotinamide adenine dinucleotide (NAD), which is needed for energy metabolism and cellular functions. Additionally, it has shown neuroprotective properties in several neurodegenerative diseases. Herein, we sought to investigate the potential protective mechanisms of NAM in an intraperitoneal (i.p) 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD) mouse model (wild-type mice (C57BL/6N), eight weeks old, average body weight 25-30 g). The study had four groups (n = 10 per group): control, MPTP (30 mg/kg i.p. for 5 days), MPTP treated with NAM (500 mg/kg, i.p for 10 days) and control treated with NAM. Our study showed that MPTP increased the expression of α-synuclein 2.5-fold, decreased tyrosine hydroxylase (TH) 0.5-fold and dopamine transporters (DAT) levels up to 0.5-fold in the striatum and substantia nigra pars compacta (SNpc), and impaired motor function. However, NAM treatment significantly reversed these PD-like pathologies. Furthermore, NAM treatment reduced oxidative stress by increasing the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) between 0.5- and 1.0-fold. Lastly, NAM treatment regulated neuroinflammation by reducing Toll-like receptor 4 (TLR-4), phosphorylated nuclear factor-κB, tumor (p-NFκB), and cyclooxygenase-2 (COX-2) levels by 0.5- to 2-fold in the PD mouse brain. Overall, these findings suggest that NAM exhibits neuroprotective properties and may be an effective therapeutic agent for PD.
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Ramos A, Joshi RS, Szabo G. Innate immune activation: Parallels in alcohol use disorder and Alzheimer’s disease. Front Mol Neurosci 2022; 15:910298. [PMID: 36157070 PMCID: PMC9505690 DOI: 10.3389/fnmol.2022.910298] [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: 04/08/2022] [Accepted: 07/18/2022] [Indexed: 11/16/2022] Open
Abstract
Alcohol use disorder is associated with systemic inflammation and organ dysfunction especially in the liver and the brain. For more than a decade, studies have highlighted alcohol abuse-mediated impairment of brain function and acceleration of neurodegeneration through inflammatory mechanisms that directly involve innate immune cells. Furthermore, recent studies indicate overlapping genetic risk factors between alcohol use and neurodegenerative disorders, specifically regarding the role of innate immunity in the pathomechanisms of both areas. Considering the pressing need for a better understanding of the relevance of alcohol abuse in dementia progression, here we summarize the molecular mechanisms of neuroinflammation observed in alcohol abuse and Alzheimer’s disease, the most common cause of dementia. In addition, we highlight mechanisms that are already established in the field of Alzheimer’s disease that may be relevant to explore in alcoholism to better understand alcohol mediated neurodegeneration and dementia, including the relevance of the liver-brain axis.
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Affiliation(s)
- Adriana Ramos
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Radhika S. Joshi
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Gyongyi Szabo
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
- Broad Institute of MIT and Harvard, Cambridge, MA, United States
- *Correspondence: Gyongyi Szabo,
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Li K, Ran B, Wang Y, Liu L, Li W. PLCγ2 impacts microglia-related effectors revealing variants and pathways important in Alzheimer’s disease. Front Cell Dev Biol 2022; 10:999061. [PMID: 36147734 PMCID: PMC9485805 DOI: 10.3389/fcell.2022.999061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 08/15/2022] [Indexed: 11/30/2022] Open
Abstract
Alzheimer’s disease (AD) is an irreversible neurodegenerative disease mainly characterized by memory loss and cognitive decline. The etiology of AD is complex and remains incompletely understood. In recent years, genome-wide association studies (GWAS) have increasingly highlighted the central role of microglia in AD pathology. As a trans-membrane receptor specifically present on the microglia in the central nervous system, phosphatidylinositol-specific phospholipase C gamma 2 (PLCγ2) plays an important role in neuroinflammation. GWAS data and corresponding pathological research have explored the effects of PLCG2 variants on amyloid burden and tau pathologies that underline AD. The link between PLCγ2 and other AD-related effectors in human and mouse microglia has also been established, placing PLCγ2 downstream of the triggering receptor expressed on myeloid cells 2 (TREM2), toll-like receptor 4 (TLR4), Bruton’s tyrosine kinase (BTK), and colony-stimulating factor 1 receptor (CSF1R). Because the research on PLCγ2’s role in AD is still in its early stages, few articles have been published, therefore in this paper, we integrate the relevant research published to date, review the structural features, expression patterns, and related pathways of PLCγ2, and summarize the recent studies on important PLCG2 variants related to AD. Furthermore, the possibility and challenge of using PLCγ2 to develop therapeutic drugs for AD are also discussed.
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Toll-Like Receptor 4: A Promising Therapeutic Target for Alzheimer's Disease. Mediators Inflamm 2022; 2022:7924199. [PMID: 36046763 PMCID: PMC9420645 DOI: 10.1155/2022/7924199] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/05/2022] [Accepted: 08/09/2022] [Indexed: 11/18/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease that primarily manifests as memory deficits and cognitive impairment and has created health challenges for patients and society. In AD, amyloid β-protein (Aβ) induces Toll-like receptor 4 (TLR4) activation in microglia. Activation of TLR4 induces downstream signaling pathways and promotes the generation of proinflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β), which also trigger the activation of astrocytes and influence amyloid-dependent neuronal death. Therefore, TLR4 may be an important molecular target for treating AD by regulating neuroinflammation. Moreover, TLR4 regulates apoptosis, autophagy, and gut microbiota and is closely related to AD. This article reviews the role of TLR4 in the pathogenesis of AD and a range of potential therapies targeting TLR4 for AD. Elucidating the regulatory mechanism of TLR4 in AD may provide valuable clues for developing new therapeutic strategies for AD.
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Microglia and microglial-based receptors in the pathogenesis and treatment of Alzheimer’s disease. Int Immunopharmacol 2022; 110:109070. [DOI: 10.1016/j.intimp.2022.109070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 07/02/2022] [Accepted: 07/14/2022] [Indexed: 11/23/2022]
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Squillace S, Salvemini D. Toll-like receptor-mediated neuroinflammation: relevance for cognitive dysfunctions. Trends Pharmacol Sci 2022; 43:726-739. [PMID: 35753845 PMCID: PMC9378500 DOI: 10.1016/j.tips.2022.05.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 05/13/2022] [Accepted: 05/27/2022] [Indexed: 10/17/2022]
Abstract
Toll-like receptors (TLRs) are pattern recognition receptors (PRRs) with a well-documented role in the innate and adaptive immune responses. Interestingly, TLR activation has also been linked to several brain functions including neurogenesis and synaptogenesis. Increasing evidence supports TLR involvement in peripheral and central inflammation underlying normal aging and the pathogenesis of clinical conditions characterized by cognitive decline. These include not only major neurodegenerative diseases but also traumatic brain injuries, surgeries, and alcohol consumption- and chemotherapy-induced cognitive impairment. We first summarize the physiological roles of TLRs in the nervous system, and then illustrate the emerging involvement of TLRs in cognitive functions, pointing to these receptors as novel enticing pharmacological targets to develop more efficient drugs for the treatment of cognitive impairment.
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Affiliation(s)
- Silvia Squillace
- Department of Pharmacology and Physiology, and the Henry and Amelia Nasrallah Center for Neuroscience, Saint Louis University School of Medicine, 1402 South Grand Boulevard, St. Louis, MO 63104, USA
| | - Daniela Salvemini
- Department of Pharmacology and Physiology, and the Henry and Amelia Nasrallah Center for Neuroscience, Saint Louis University School of Medicine, 1402 South Grand Boulevard, St. Louis, MO 63104, USA.
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Forloni G, La Vitola P, Balducci C. Oligomeropathies, inflammation and prion protein binding. Front Neurosci 2022; 16:822420. [PMID: 36081661 PMCID: PMC9445368 DOI: 10.3389/fnins.2022.822420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 07/28/2022] [Indexed: 11/13/2022] Open
Abstract
The central role of oligomers, small soluble aggregates of misfolded proteins, in the pathogenesis of neurodegenerative disorders is recognized in numerous experimental conditions and is compatible with clinical evidence. To underline this concept, some years ago we coined the term oligomeropathies to define the common mechanism of action of protein misfolding diseases like Alzheimer, Parkinson or prion diseases. Using simple experimental conditions, with direct application of synthetic β amyloid or α-synuclein oligomers intraventricularly at micromolar concentrations, we could detect differences and similarities in the biological consequences. The two oligomer species affected cognitive behavior, neuronal dysfunction and cerebral inflammatory reactions with distinct mechanisms. In these experimental conditions the proposed mediatory role of cellular prion protein in oligomer activities was not confirmed. Together with oligomers, inflammation at different levels can be important early in neurodegenerative disorders; both β amyloid and α-synuclein oligomers induce inflammation and its control strongly affects neuronal dysfunction. This review summarizes our studies with β-amyloid or α-synuclein oligomers, also considering the potential curative role of doxycycline, a well-known antibiotic with anti-amyloidogenic and anti-inflammatory activities. These actions are analyzed in terms of the therapeutic prospects.
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Ganz T, Fainstein N, Ben-Hur T. When the infectious environment meets the AD brain. Mol Neurodegener 2022; 17:53. [PMID: 35986296 PMCID: PMC9388962 DOI: 10.1186/s13024-022-00559-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 08/08/2022] [Indexed: 11/23/2022] Open
Abstract
Background The Amyloid theory of Alzheimer’s disease (AD) suggests that the deposition of Amyloid β (Aβ) in the brain triggers a chain of events, involving the deposition of phosphorylated Tau and other misfolded proteins, leading to neurodegeneration via neuroinflammation, oxidative stress, and neurovascular factors. The infectious theory linked various infectious agents with the development of AD, raising the possibility that they serve as etiological causes of the disease. Are these theories mutually exclusive, or do they coincide? Main body In this review, we will discuss how the two theories converge. We present a model by which (1) the systemic infectious burden accelerates the development of AD brain pathology via bacterial Amyloids and other pathogen-associated molecular patterns (PAMPs), and (2) the developing AD brain pathology increases its susceptibility to the neurotoxicity of infectious agents -derived PAMPs, which drive neurodegeneration via activated microglia. Conclusions The reciprocal effects of amyloid deposition and systemic infectious burden may lead to a vicious cycle fueling Alzheimer’s disease pathogenesis.
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Singh D. Astrocytic and microglial cells as the modulators of neuroinflammation in Alzheimer's disease. J Neuroinflammation 2022; 19:206. [PMID: 35978311 PMCID: PMC9382837 DOI: 10.1186/s12974-022-02565-0] [Citation(s) in RCA: 92] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 08/06/2022] [Indexed: 12/17/2022] Open
Abstract
Neuroinflammation is instigated by the misfiring of immune cells in the central nervous system (CNS) involving microglia and astrocytes as key cell-types. Neuroinflammation is a consequence of CNS injury, infection, toxicity, or autoimmunity. It is favorable as well as a detrimental process for neurodevelopment and associated processes. Transient activation of inflammatory response involving release of cytokines and growth factors positively affects the development and post-injury tissue. However, chronic or uncontrolled inflammatory responses may lead to various neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis, and multiple sclerosis. These diseases have variable clinical and pathological features, but are underlaid by the aggregation of misfolded proteins with a cytotoxic effect. Notably, abnormal activation of glial cells could mediate neuroinflammation, leading to the neurodegenerative condition. Microglia, a type of glial cell, a resident immune cell, form the forefront defense of the CNS immune system. Dysfunctional microglia and astrocyte, a different kind of glial cell with homeostatic function, impairs the protein aggregate (amyloid-beta plaque) clearance in AD. Studies have shown that microglia and astrocytes undergo alterations in their genetic profile, cellular and molecular responses, and thus promote dysfunctional immune cross-talk in AD. Hence, targeting microglia and astrocytes-driven molecular pathways could resolve the particular layers of neuroinflammation and set a reliable therapeutic intervention in AD progression.
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Affiliation(s)
- Deepali Singh
- National Brain Research Centre, Manesar, Haryana, 122052, India.
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1-L Transcription in Alzheimer's Disease. Curr Issues Mol Biol 2022; 44:3533-3551. [PMID: 36005139 PMCID: PMC9406503 DOI: 10.3390/cimb44080243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/04/2022] [Accepted: 08/06/2022] [Indexed: 11/23/2022] Open
Abstract
Alzheimer’s disease is a very complex disease and better explanations and models are needed to understand how neurons are affected and microglia are activated. A new model of Alzheimer’s disease is presented here, the β-amyloid peptide is considered an important RNA recognition/binding peptide. 1-L transcription revealed compatible sequences with AAUAAA (PAS signal) and UUUC (class III ARE rich in U) in the Aβ peptide, supporting the peptide–RNA regulatory model. When a hypothetical model of fibril selection with the prionic character of amyloid assemblies is added to the peptide-RNA regulatory model, the downregulation of the PI3K-Akt pathway and the upregulation of the PLC-IP3 pathway are well explained. The model explains why neurons are less protected from inflammation and why microglia are activated; why mitochondria are destabilized; why the autophagic flux is destabilized; and why the post-transcriptional attenuation of the axonal signal “noise” is interrupted. For example, the model suggests that Aβ peptide may post-transcriptionally control ELAVL2 (ELAV-like RNA binding protein 2) and DCP2 (decapping mRNA protein 2), which are known to regulate RNA processing, transport, and stability.
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Li Y, Zhu S, Xie K, Feng X, Chen L, Wu X, Sun Z, Shu G, Wang S, Zhu C, Gao P, Jiang Q, Wang L. TLR4 in Tph2 neurons modulates anxiety-related behaviors in a sex-dependent manner. Neuropharmacology 2022; 216:109175. [PMID: 35787402 DOI: 10.1016/j.neuropharm.2022.109175] [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: 12/30/2021] [Revised: 06/09/2022] [Accepted: 06/27/2022] [Indexed: 11/18/2022]
Abstract
TLR4 belongs to the TLR receptor family and can induce a proinflammatory response to invading pathogens. Recent studies have identified that TLR4 is associated with major anxiety disorder. Tph2 is a rate-limiting enzyme for 5-HT biosynthesis that is expressed at high levels in the DRN, which includes the main 5-HT projection to the hippocampus and prefrontal cortex and regulates anxiety disorder. Here, we show that TLR4 expressed in Tph2 neurons in the DRN can modulate anxiety-like behaviors in a sex-dependent manner. Deletion of TLR4 in Tph2 neurons decreases anxiety-like behaviors in male but not in female mice. Meanwhile, a similar phenotype was found by selectively ablating TLR4 in the DRN of adult male but not female mice using AAV-Cre-GFP virus. Inhibition of TLR4 in DRN by infusion of LPS-RS via intra-Aq is sufficient to reverse anxiety-like behavior induced by chronic immobilization stress (CIS). The underlying mechanisms seem to involve alterations in the excitability of Tph2 neurons and key components of 5-HT transmission, including synthesis, reuptake, and transmission. Our results suggest that TLR4 in Tph2 neurons is a key modulator in anxiety-like behaviors and the 5-HT system in the brain between different sexes.
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Affiliation(s)
- Yongxiang Li
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Shuqing Zhu
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Kailai Xie
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Xiajie Feng
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Lvshuang Chen
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Xin Wu
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Zhonghua Sun
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Gang Shu
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Songbo Wang
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Canjun Zhu
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Ping Gao
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Qingyan Jiang
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China.
| | - Lina Wang
- Guangdong Provincial Key Laboratory of Animal Nutrition Control, Guangzhou, Guangdong, 510642, China; National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, Guangdong, 510642, China.
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Chen SH, Han S, Hu CF, Zhou R, Gao Y, Tu D, Gao H, Feng J, Wang Y, Lu RB, Hong JS. Activation of the MAC1-ERK1/2-NOX2 Pathway Is Required for LPS-Induced Sustaining Reactive Microgliosis, Chronic Neuroinflammation and Neurodegeneration. Antioxidants (Basel) 2022; 11:1202. [PMID: 35740099 PMCID: PMC9220294 DOI: 10.3390/antiox11061202] [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: 05/24/2022] [Revised: 06/13/2022] [Accepted: 06/16/2022] [Indexed: 11/24/2022] Open
Abstract
Recent studies suggest that improper resolution of acute neuroinflammation may lead to long-lasting low-grade chronic neuroinflammation and drive progressive neurodegeneration. However, the molecular mechanism underlying the transition from acute to chronic neuroinflammation remains unclear. The main purpose of this study was to search for potential pathways mediating LPS-elicited chronic neuroinflammation and resultant neurodegeneration. Using microglia cultures prepared from C57BL/6J, MAC1-deficient, and MyD88-deficient mice, the initial study showed that activation of TLR-4 is not sufficient for maintaining chronic neuroinflammation despite its essential role in LPS-initiated acute neuroinflammation. Opposite to TLR-4, our studies showed significantly reduced intensity of chronic neuroinflammation, oxidative stress, and progressive loss of nigral dopaminergic neurons in MAC1-deficient neuron/glial cultures or mice stimulated with LPS. Mechanistic studies revealed the essential role ERK1/2 activation in chronic neuroinflammation-elicited neurodegeneration, which was demonstrated by using an ERK1/2 inhibitor in neuron-glial cultures. Taken together, we propose a key role of the MAC1-NOX2-ERK1/2 signaling pathway in the initiation and maintenance of low-grade chronic neuroinflammation. Continuing ERK1/2 phosphorylation and NOX2 activation form a vicious feedforward cycle in microglia to maintain the low-grade neuroinflammation and drive neurodegeneration.
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Affiliation(s)
- Shih-Heng Chen
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA; (S.H.); (C.-F.H.); (R.Z.); (Y.G.); (D.T.); (Y.W.); (J.-S.H.)
| | - Shuangyu Han
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA; (S.H.); (C.-F.H.); (R.Z.); (Y.G.); (D.T.); (Y.W.); (J.-S.H.)
- Respiratory Department, Tianjin Medical University General Hospital, Tianjin 300052, China;
| | - Chih-Fen Hu
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA; (S.H.); (C.-F.H.); (R.Z.); (Y.G.); (D.T.); (Y.W.); (J.-S.H.)
- Department of Pediatrics, Tri-Service General Hospital, National Defense Medical Center, Taipei 10086, Taiwan
| | - Ran Zhou
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA; (S.H.); (C.-F.H.); (R.Z.); (Y.G.); (D.T.); (Y.W.); (J.-S.H.)
- Respiratory Department, Tianjin Medical University General Hospital, Tianjin 300052, China;
| | - Yun Gao
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA; (S.H.); (C.-F.H.); (R.Z.); (Y.G.); (D.T.); (Y.W.); (J.-S.H.)
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Institute for Brain Sciences, Nanjing University, Nanjing 210061, China;
| | - Dezhen Tu
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA; (S.H.); (C.-F.H.); (R.Z.); (Y.G.); (D.T.); (Y.W.); (J.-S.H.)
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Institute for Brain Sciences, Nanjing University, Nanjing 210061, China;
| | - Huiming Gao
- MOE Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Institute for Brain Sciences, Nanjing University, Nanjing 210061, China;
| | - Jing Feng
- Respiratory Department, Tianjin Medical University General Hospital, Tianjin 300052, China;
| | - Yubao Wang
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA; (S.H.); (C.-F.H.); (R.Z.); (Y.G.); (D.T.); (Y.W.); (J.-S.H.)
- Institute of Infectious Diseases, The Second Hospital of Tianjin Medical University, Tianjin 300211, China
| | - Ru-Band Lu
- Institute of Behavioral Medicine, National Cheng Kung University, Tainan 70101, Taiwan;
| | - Jau-Shyong Hong
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA; (S.H.); (C.-F.H.); (R.Z.); (Y.G.); (D.T.); (Y.W.); (J.-S.H.)
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