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Grayson C, Mailloux RJ. Coenzyme Q 10 and nicotinamide nucleotide transhydrogenase: Sentinels for mitochondrial hydrogen peroxide signaling. Free Radic Biol Med 2023; 208:260-271. [PMID: 37573896 DOI: 10.1016/j.freeradbiomed.2023.08.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 07/21/2023] [Accepted: 08/08/2023] [Indexed: 08/15/2023]
Abstract
Mitochondria use hydrogen peroxide (H2O2) as a mitokine for cell communication. H2O2 output for signaling depends on its rate of production and degradation, both of which are strongly affected by the redox state of the coenzyme Q10 (CoQ) pool and NADPH availability. Here, we propose the CoQ pool and nicotinamide nucleotide transhydrogenase (NNT) have evolved to be central modalities for mitochondrial H2O2 signaling. Both factors play opposing yet equally important roles in dictating H2O2 availability because they are connected to one another by two central parameters in bioenergetics: electron supply and Δp. The CoQ pool is the central point of convergence for electrons from various dehydrogenases and the electron transport chain (ETC). The increase in Δp creates a significant amount of protonic backpressure on mitochondria to promote H2O2 genesis through CoQ pool reduction. These same factors also drive the activity of NNT, which uses electrons and the Δp to eliminate H2O2. In this way, electron supply and the magnitude of the Δp manifests as a redox connection between the two sentinels, CoQ and NNT, which serve as opposing yet equally important forces required for budgeting H2O2. Taken together, CoQ and NNT are sentinels linked through mitochondrial bioenergetics to manage H2O2 availability for interorganelle and intercellular redox signaling.
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Affiliation(s)
- Cathryn Grayson
- The School of Human Nutrition, Faculty of Agricultural and Environmental Sciences, McGill University, Ste.-Anne-de-Bellevue, Quebec, Canada
| | - Ryan J Mailloux
- The School of Human Nutrition, Faculty of Agricultural and Environmental Sciences, McGill University, Ste.-Anne-de-Bellevue, Quebec, Canada.
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Rentz T, Dorighello GG, dos Santos RR, Barreto LM, Freitas IN, Lazaro CM, Razolli DS, Cazita PM, Oliveira HCF. CETP Expression in Bone-Marrow-Derived Cells Reduces the Inflammatory Features of Atherosclerosis in Hypercholesterolemic Mice. Biomolecules 2023; 13:1556. [PMID: 37892238 PMCID: PMC10605246 DOI: 10.3390/biom13101556] [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: 09/04/2023] [Revised: 10/13/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023] Open
Abstract
CETP activity reduces plasma HDL-cholesterol concentrations, a correlate of an increased risk of atherosclerotic events. However, our recent findings suggest that CETP expression in macrophages promotes an intracellular antioxidant state, reduces free cholesterol accumulation and phagocytosis, and attenuates pro-inflammatory gene expression. To determine whether CETP expression in macrophages affects atherosclerosis development, we transplanted bone marrow from transgenic mice expressing simian CETP or non-expressing littermates into hypercholesterolemic LDL-receptor-deficient mice. The CETP expression did not change the lipid-stained lesion areas but decreased the macrophage content (CD68), neutrophil accumulation (LY6G), and TNF-α aorta content of young male transplanted mice and decreased LY6G, TNF-α, iNOS, and nitrotyrosine (3-NT) in aged female transplanted mice. These findings suggest that CETP expression in bone-marrow-derived cells reduces the inflammatory features of atherosclerosis. These novel mechanistic observations may help to explain the failure of CETP inhibitors in reducing atherosclerotic events in humans.
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Affiliation(s)
- Thiago Rentz
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas 13083-862, SP, Brazil; (T.R.); (G.G.D.); (L.M.B.); (I.N.F.); (C.M.L.)
| | - Gabriel G. Dorighello
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas 13083-862, SP, Brazil; (T.R.); (G.G.D.); (L.M.B.); (I.N.F.); (C.M.L.)
| | - Renata R. dos Santos
- Division of Radiotherapy, Medical School Hospital, Faculty of Medical Sciences, State University of Campinas, Campinas 13083-887, SP, Brazil;
| | - Lohanna M. Barreto
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas 13083-862, SP, Brazil; (T.R.); (G.G.D.); (L.M.B.); (I.N.F.); (C.M.L.)
| | - Israelle N. Freitas
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas 13083-862, SP, Brazil; (T.R.); (G.G.D.); (L.M.B.); (I.N.F.); (C.M.L.)
| | - Carolina M. Lazaro
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas 13083-862, SP, Brazil; (T.R.); (G.G.D.); (L.M.B.); (I.N.F.); (C.M.L.)
| | - Daniela S. Razolli
- Obesity and Comorbidities Research Center, State University of Campinas, Campinas 13083-864, SP, Brazil;
| | - Patricia M. Cazita
- Laboratório de Lípides (LIM10), Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo 01246-903, SP, Brazil;
| | - Helena C. F. Oliveira
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas 13083-862, SP, Brazil; (T.R.); (G.G.D.); (L.M.B.); (I.N.F.); (C.M.L.)
- Obesity and Comorbidities Research Center, State University of Campinas, Campinas 13083-864, SP, Brazil;
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Tff3 Deficiency Protects against Hepatic Fat Accumulation after Prolonged High-Fat Diet. LIFE (BASEL, SWITZERLAND) 2022; 12:life12081288. [PMID: 36013467 PMCID: PMC9409972 DOI: 10.3390/life12081288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/09/2022] [Accepted: 08/11/2022] [Indexed: 11/17/2022]
Abstract
Trefoil factor 3 (Tff3) protein is a small secretory protein expressed on various mucosal surfaces and is involved in proper mucosal function and recovery via various mechanisms, including immune response. However, Tff3 is also found in the bloodstream and in various other tissues, including the liver. Its complete attenuation was observed as the most prominent event in the early phase of diabetes in the polygenic Tally Ho mouse model of diabesity. Since then, its role in metabolic processes has emerged. To elucidate the complex role of Tff3, we used a new Tff3-deficient mouse model without additional metabolically relevant mutations (Tff3-/-/C57BL/6NCrl) and exposed it to a high-fat diet (HFD) for a prolonged period (8 months). The effect was observed in male and female mice compared to wild-type (WT) counter groups (n = 10 animals per group). We monitored the animals’ general metabolic parameters, liver morphology, ultrastructure and molecular genes in relevant lipid and inflammatory pathways. Tff3-deficient male mice had reduced body weight and better glucose utilization after 17 weeks of HFD, but longer HFD exposure (32 weeks) resulted in no such change. We found a strong reduction in lipid accumulation in male Tff3-/-/C57BL/6NCrl mice and a less prominent reduction in female mice. This was associated with downregulated peroxisome proliferator-activated receptor gamma (Pparγ) and upregulated interleukin-6 (Il-6) gene expression, although protein level difference did not reach statistical significance due to higher individual variations. Tff3-/-/C57Bl6N mice of both sex had reduced liver steatosis, without major fatty acid content perturbations. Our research shows that Tff3 protein is clearly involved in complex metabolic pathways. Tff3 deficiency in C57Bl6N genetic background caused reduced lipid accumulation in the liver; further research is needed to elucidate its precise role in metabolism-related events.
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Figueira TR, Castilho RF. Insights on how mitochondrial NAD(P) + transhydrogenase plays a central metabolic role in proinflammatory macrophages. Am J Physiol Cell Physiol 2022; 323:C648-C649. [PMID: 35938879 DOI: 10.1152/ajpcell.00090.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Tiago R Figueira
- School of Physical Education and Sport of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, Brazil
| | - Roger F Castilho
- School of Medical Sciences, Department of Pathology, University of Campinas (UNICAMP), Campinas, Brazil
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Francisco A, Figueira TR, Castilho RF. Mitochondrial NAD(P) + Transhydrogenase: From Molecular Features to Physiology and Disease. Antioxid Redox Signal 2022; 36:864-884. [PMID: 34155914 DOI: 10.1089/ars.2021.0111] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Significance: Proton-translocating NAD(P)+ transhydrogenase, also known as nicotinamide nucleotide transhydrogenase (NNT), catalyzes a reversible reaction coupling the protonmotive force across the inner mitochondrial membrane and hydride (H-, a proton plus two electrons) transfer between the mitochondrial pools of NAD(H) and NADP(H). The forward NNT reaction is a source of NADPH in the mitochondrial matrix, fueling antioxidant and biosynthetic pathways with reductive potential. Despite the greater emphasis given to the net forward reaction, the reverse NNT reaction that oxidizes NADPH also occurs in physiological and pathological conditions. Recent Advances: NNT (dys)function has been linked to various metabolic pathways and disease phenotypes. Most of these findings have been based on spontaneous loss-of-function Nnt mutations found in the C57BL/6J mouse strain (NntC57BL/6J mutation) and disease-causing Nnt mutations in humans. The present review focuses on recent advances based on the mouse NntC57BL/6J mutation. Critical Issues: Most studies associating NNT function with disease phenotypes have been based on comparisons between different strains of inbred mice (with or without the NntC57BL/6J mutation), which creates uncertainties over the actual contribution of NNT in the context of other potential genetic modifiers. Future Directions: Future research might contribute to understanding the role of NNT in pathological conditions and elucidate how NNT regulates physiological signaling through its forward and reverse reactions. The importance of NNT in redox balance and tumor cell proliferation makes it a potential target of new therapeutic strategies for oxidative-stress-mediated diseases and cancer. Antioxid. Redox Signal. 36, 864-884.
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Affiliation(s)
- Annelise Francisco
- Department of Pathology, Faculty of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
| | - Tiago Rezende Figueira
- School of Physical Education and Sport of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, Brazil
| | - Roger Frigério Castilho
- Department of Pathology, Faculty of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
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Bharath LP, Regan T, Conway R. Regulation of Immune Cell Function by Nicotinamide Nucleotide Transhydrogenase. Am J Physiol Cell Physiol 2022; 322:C666-C673. [PMID: 35138175 PMCID: PMC8977145 DOI: 10.1152/ajpcell.00607.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Redox homeostasis is elemental for the normal physiology of all cell types. Cells use multiple mechanisms to regulate the redox balance tightly. The onset and progression of many metabolic and aging-associated diseases occur due to the dysregulation of redox homeostasis. Thus, it is critical to identify and therapeutically target mechanisms that precipitate abnormalities in redox balance. Reactive oxygen species (ROS) produced within the immune cells regulate homeostasis, hyperimmune and hypoimmune cell responsiveness, apoptosis, immune response to pathogens, and tumor immunity. Immune cells have both cytosolic and organelle-specific redox regulatory systems to maintain appropriate levels of ROS. Nicotinamide nucleotide transhydrogenase (NNT) is an essential mitochondrial redox regulatory protein. Dysregulation of NNT function prevents immune cells from mounting an adequate immune response to pathogens, promotes a chronic inflammatory state associated with aging and metabolic diseases, and initiates conditions related to a dysregulated immune system such as autoimmunity. While many studies have reported on NNT in different cell types, including cancer cells, relatively few studies have explored NNT in immune cells. This review provides an overview of NNT and focuses on the current knowledge of NNT in the immune cells.
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Affiliation(s)
- Leena P Bharath
- Department of Nutrition and Public Health, Merrimack College, North Andover, Massachusetts, United States
| | - Thomas Regan
- Department of Nutrition and Public Health, Merrimack College, North Andover, Massachusetts, United States
| | - Rachel Conway
- Department of Nutrition and Public Health, Merrimack College, North Andover, Massachusetts, United States
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Rawle DJ, Le TT, Dumenil T, Bishop C, Yan K, Nakayama E, Bird PI, Suhrbier A. Widespread discrepancy in Nnt genotypes and genetic backgrounds complicates granzyme A and other knockout mouse studies. eLife 2022; 11:e70207. [PMID: 35119362 PMCID: PMC8816380 DOI: 10.7554/elife.70207] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 01/10/2022] [Indexed: 02/06/2023] Open
Abstract
Granzyme A (GZMA) is a serine protease secreted by cytotoxic lymphocytes, with Gzma-/- mouse studies having informed our understanding of GZMA's physiological function. We show herein that Gzma-/- mice have a mixed C57BL/6J and C57BL/6N genetic background and retain the full-length nicotinamide nucleotide transhydrogenase (Nnt) gene, whereas Nnt is truncated in C57BL/6J mice. Chikungunya viral arthritis was substantially ameliorated in Gzma-/- mice; however, the presence of Nnt and the C57BL/6N background, rather than loss of GZMA expression, was responsible for this phenotype. A new CRISPR active site mutant C57BL/6J GzmaS211A mouse provided the first insights into GZMA's bioactivity free of background issues, with circulating proteolytically active GZMA promoting immune-stimulating and pro-inflammatory signatures. Remarkably, k-mer mining of the Sequence Read Archive illustrated that ≈27% of Run Accessions and ≈38% of BioProjects listing C57BL/6J as the mouse strain had Nnt sequencing reads inconsistent with a C57BL/6J genetic background. Nnt and C57BL/6N background issues have clearly complicated our understanding of GZMA and may similarly have influenced studies across a broad range of fields.
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Affiliation(s)
- Daniel J Rawle
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
| | - Thuy T Le
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
| | - Troy Dumenil
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
| | - Cameron Bishop
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
| | - Kexin Yan
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
| | - Eri Nakayama
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
- Department of Virology I, National Institute of Infectious DiseasesTokyoJapan
| | - Phillip I Bird
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash UniversityMelbourneAustralia
| | - Andreas Suhrbier
- QIMR Berghofer Medical Research InstituteBrisbaneAustralia
- Australian Infectious Disease Research Centre, GVN Center of ExcellenceBrisbaneAustralia
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Chen S, Wang J, Zhang L, Xia H. Experimental study on alleviating atherosclerosis through intervention of mitochondrial calcium transport and calcium-induced membrane permeability transition. J Investig Med 2021; 69:1156-1160. [PMID: 33906902 DOI: 10.1136/jim-2020-001765] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2021] [Indexed: 01/23/2023]
Abstract
To investigate the effort of mitochondrial calcium transport and calcium-induced membrane permeability transition in alleviating atherosclerosis. The experimental mice were divided into three groups: the control group (C57BL/6 mice with normal diet), the atherosclerosis group (apolipoprotein E-deficient (ApoE-/-) mice with high-fat diet) and the mitochondrial targeting agent group (ApoE-/- mouse with high-fat diet). The mean fluorescence intensity of Ca2+ in the atherosclerosis group is significantly higher than control group and mitochondrial targeting agent group. But the mean fluorescence intensity of Ca2+-ATPase is lower than other groups. The macrophage recruitment (F4/80 positive area) and the expression of tumor necrosis factor alpha, interleukin-6, pyrin domain containing protein 3, intercellular cell adhesion molecule-1, p38 mitogen-activated protein kinase and Jun kinase 1/2 phosphorylation in the atherosclerosis group are higher that other groups. Treatment with mitochondrial targeting agents reduced the levels of elevated cyt C and cleaved caspase-3 in atherosclerotic mice (p<0.05). Mitochondrial targeting agents interfere with mitochondrial calcium transport and calcium-induced membrane permeability transition, inhibit MAPK/JNK pathway activation, inhibit foam cell formation and alleviate the process of atherosclerosis.
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Affiliation(s)
- Sisi Chen
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Jianing Wang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.,Department of Cardiology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Lei Zhang
- Department of Cardiology and Institute of Clinical Medicine, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Hao Xia
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China .,Cardiovascular Research Institute, Wuhan University, Wuhan, Hubei, China.,Hubei Key Laboratory of Cardiology, Wuhan, Hubei, China
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Raposo HF, Forsythe P, Chausse B, Castelli JZ, Moraes-Vieira PM, Nunes VS, Oliveira HCF. Novel role of cholesteryl ester transfer protein (CETP): attenuation of adiposity by enhancing lipolysis and brown adipose tissue activity. Metabolism 2021; 114:154429. [PMID: 33166579 DOI: 10.1016/j.metabol.2020.154429] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 10/13/2020] [Accepted: 11/04/2020] [Indexed: 01/07/2023]
Abstract
OBJECTIVE The systemic function of CETP has been well characterized. CETP plasma activity reduces HDL cholesterol and thus increases the risk of atherosclerosis. Here, we investigated whether CETP expression modulate adiposity. METHODS Body adiposity and energy metabolism related assays and gene/protein expression were compared in CETP transgenic and non-transgenic mice and in hamsters treated with CETP neutralizing antibody. RESULTS We found that transgenic mice expressing human CETP present less white adipose tissue mass and lower leptinemia than nontransgenic (NTg) littermates. No differences were found in physical activity, food intake, fat fecal excretion, lipogenesis or exogenous lipid accumulation in adipose depots. Nonetheless, adipose lipolysis rates and whole-body energy expenditure were elevated in CETP mice. In accordance, lipolysis-related gene expression and protein content were increased in visceral and brown adipose tissue (BAT). In addition, we verified increased BAT temperature and oxygen consumption. These results were confirmed in two other animal models: 1) hamsters treated with CETP neutralizing antibody and 2) an independent line of transgenic mice expressing simian CETP. CONCLUSIONS These findings reveal a novel anti-adipogenic role for CETP.
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Affiliation(s)
- Helena F Raposo
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas, SP, Brazil; Obesity and Comorbidities Research Center, Institute of Biology, State University of Campinas, Campinas, SP, Brazil
| | - Patricia Forsythe
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas, SP, Brazil
| | - Bruno Chausse
- Obesity and Comorbidities Research Center, Institute of Biology, State University of Campinas, Campinas, SP, Brazil
| | - Júlia Z Castelli
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas, SP, Brazil; Obesity and Comorbidities Research Center, Institute of Biology, State University of Campinas, Campinas, SP, Brazil
| | - Pedro M Moraes-Vieira
- Obesity and Comorbidities Research Center, Institute of Biology, State University of Campinas, Campinas, SP, Brazil; Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, State University of Campinas, Campinas, SP, Brazil; Experimental Medicine Research Cluster (EMRC), State University of Campinas, SP, Brazil
| | - Valéria S Nunes
- Laboratorio de Lipides (LIM10), Hospital das Clínicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, SP, Brazil
| | - Helena C F Oliveira
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas, SP, Brazil; Obesity and Comorbidities Research Center, Institute of Biology, State University of Campinas, Campinas, SP, Brazil.
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Low-density lipoprotein receptor (LDLR) regulates NLRP3-mediated neuronal pyroptosis following cerebral ischemia/reperfusion injury. J Neuroinflammation 2020; 17:330. [PMID: 33153475 PMCID: PMC7643474 DOI: 10.1186/s12974-020-01988-x] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 10/07/2020] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Inflammatory response has been recognized as a pivotal pathophysiological process during cerebral ischemic stroke. NLRP3 inflammasome, involved in the regulation of inflammatory cascade, can simultaneously lead to GSDMD-executed pyroptosis in cerebral ischemia. Low-density lipoprotein receptor (LDLR), responsible for cholesterol uptake, was noted to exert potential anti-inflammatory bioactivities. Nevertheless, the role of LDLR in neuroinflammation mobilized by cerebral ischemia/reperfusion (I/R) has not been investigated. METHODS Ischemic stroke mice model was accomplished by middle cerebral artery occlusion. Oxygen-glucose deprivation was employed after primary cortical neuron was extracted and cultured. A pharmacological inhibitor of NLRP3 (CY-09) was administered to suppress NLPR3 activation. Histological and biochemical analysis were performed to assess the neuronal death both in vitro and in vivo. In addition, neurological deficits and behavioral deterioration were evaluated in mice. RESULTS The expression of LDLR was downregulated following cerebral I/R injury. Genetic knockout of Ldlr enhanced caspase-1-dependent cleavage of GSDMD and resulted in severe neuronal pyroptosis. LDLR deficiency contributed to excessive NLRP3-mediated maturation and release of IL-1β and IL-18 under in vitro and in vivo ischemic conditions. These influences ultimately led to aggravated neurological deficits and long-term cognitive dysfunction. Blockade of NLRP3 substantially retarded neuronal pyroptosis in Ldlr-/- mice and cultured Ldlr-/- neuron after experimental stroke. CONCLUSIONS These results demonstrated that LDLR modulates NLRP3-mediated neuronal pyroptosis and neuroinflammation following ischemic stroke. Our findings characterize a novel role for LDLR as a potential therapeutic target in neuroinflammatory responses to acute cerebral ischemic injury.
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