1
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Olabiyi BF, Schmoele AC, Beins EC, Zimmer A. Pharmacological blockade of cannabinoid receptor 2 signaling does not affect LPS/IFN-γ-induced microglial activation. Sci Rep 2023; 13:11105. [PMID: 37429837 PMCID: PMC10333177 DOI: 10.1038/s41598-023-37702-z] [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: 02/28/2023] [Accepted: 06/26/2023] [Indexed: 07/12/2023] Open
Abstract
Cannabinoid receptor 2 (CB2) signaling modulates microglial responses to inflammatory stimuli. Our previous studies demonstrated that genetic deletion of CB2 inhibits microglial activation during inflammatory stimulation of toll-like receptors (TLRs) or in neurodegenerative conditions. However, we cannot exclude developmental effects of the constitutive CB2 knockout (CB2-/-), which could mediate compensatory outcomes in CB2-/- mice. In the present study, we therefore tested whether acute pharmacological inhibition of CB2 receptor has a similar effect on microglial activation as in CB2-/- in response to inflammatory stimulation. Our findings suggest that the CB2-specific antagonist SR144528 has little or no effect on LPS/IFN-γ-induced activation in primary microglia or organotypic hippocampal slice cultures at nanomolar concentrations. We show that SR144528 did not alter LPS/IFN-γ-mediated microglial cytokine secretion, Iba1 and CD68 staining intensity or morphology at 1 and 10 nM. Although SR144528 suppressed LPS/IFN-γ-induced microglial activation at 1 µM, this anti-inflammatory effect was not dependent on CB2 receptors and exceeded the Ki on CB2 receptors by more than a thousand-fold. Thus, SR144528 does not mimic the anti-inflammatory effects observed in the CB2-/- microglia after LPS/IFN-γ stimulation. Therefore, we propose that the deletion of CB2 probably triggered an adaptive mechanism, making microglia less responsive to inflammatory stimulation.
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Affiliation(s)
| | | | - Eva Carolina Beins
- Institute of Molecular Psychiatry, Medical Faculty, University of Bonn, Bonn, Germany
- Institute of Human Genetics, University of Bonn, School of Medicine & University Hospital Bonn, Bonn, Germany
| | - Andreas Zimmer
- Institute of Molecular Psychiatry, Medical Faculty, University of Bonn, Bonn, Germany.
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2
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Cervantes J, Kanter JE. Monocyte and macrophage foam cells in diabetes-accelerated atherosclerosis. Front Cardiovasc Med 2023; 10:1213177. [PMID: 37378396 PMCID: PMC10291141 DOI: 10.3389/fcvm.2023.1213177] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 05/30/2023] [Indexed: 06/29/2023] Open
Abstract
Diabetes results in an increased risk of atherosclerotic cardiovascular disease. This minireview will discuss whether monocyte and macrophage lipid loading contribute to this increased risk, as monocytes and macrophages are critically involved in the progression of atherosclerosis. Both uptake and efflux pathways have been described as being altered by diabetes or conditions associated with diabetes, which may contribute to the increased accumulation of lipids seen in macrophages in diabetes. More recently, monocytes have also been described as lipid-laden in response to elevated lipids, including triglyceride-rich lipoproteins, the class of lipids often elevated in the setting of diabetes.
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Affiliation(s)
| | - Jenny E. Kanter
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA, United States
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3
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ACAT1/SOAT1 Blockade Suppresses LPS-Mediated Neuroinflammation by Modulating the Fate of Toll-like Receptor 4 in Microglia. Int J Mol Sci 2023; 24:ijms24065616. [PMID: 36982689 PMCID: PMC10053317 DOI: 10.3390/ijms24065616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 03/08/2023] [Accepted: 03/08/2023] [Indexed: 03/17/2023] Open
Abstract
Cholesterol is stored as cholesteryl esters by the enzymes acyl-CoA:cholesterol acyltransferases/sterol O:acyltransferases (ACATs/SOATs). ACAT1 blockade (A1B) ameliorates the pro-inflammatory responses of macrophages to lipopolysaccharides (LPS) and cholesterol loading. However, the mediators involved in transmitting the effects of A1B in immune cells is unknown. Microglial Acat1/Soat1 expression is elevated in many neurodegenerative diseases and in acute neuroinflammation. We evaluated LPS-induced neuroinflammation experiments in control vs. myeloid-specific Acat1/Soat1 knockout mice. We also evaluated LPS-induced neuroinflammation in microglial N9 cells with and without pre-treatment with K-604, a selective ACAT1 inhibitor. Biochemical and microscopy assays were used to monitor the fate of Toll-Like Receptor 4 (TLR4), the receptor at the plasma membrane and the endosomal membrane that mediates pro-inflammatory signaling cascades. In the hippocampus and cortex, results revealed that Acat1/Soat1 inactivation in myeloid cell lineage markedly attenuated LPS-induced activation of pro-inflammatory response genes. Studies in microglial N9 cells showed that pre-incubation with K-604 significantly reduced the LPS-induced pro-inflammatory responses. Further studies showed that K-604 decreased the total TLR4 protein content by increasing TLR4 endocytosis, thus enhancing the trafficking of TLR4 to the lysosomes for degradation. We concluded that A1B alters the intracellular fate of TLR4 and suppresses its pro-inflammatory signaling cascade in response to LPS.
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4
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Bhattacharjee P, Rutland N, Iyer MR. Targeting Sterol O-Acyltransferase/Acyl-CoA:Cholesterol Acyltransferase (ACAT): A Perspective on Small-Molecule Inhibitors and Their Therapeutic Potential. J Med Chem 2022; 65:16062-16098. [PMID: 36473091 DOI: 10.1021/acs.jmedchem.2c01265] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Sterol O-acyltransferase (SOAT) is a membrane-bound enzyme that aids the esterification of cholesterol and fatty acids to cholesterol esters. SOAT has been studied extensively as a potential drug target, since its inhibition can serve as an alternative to statin therapy. Two SOAT isozymes that have discrete functions in the human body, namely, SOAT1 and SOAT2, have been characterized. Over three decades of research has focused on candidate SOAT1 inhibitors with unsatisfactory results in clinical trials. Recent research has focused on targeting SOAT2 selectively. In this perspective, we summarize the literature covering various SOAT inhibitory agents and discuss the design, structural requirements, and mode of action of SOAT inhibitors.
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Affiliation(s)
- Pinaki Bhattacharjee
- Section on Medicinal Chemistry, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, 5625 Fishers Lane, Rockville, Maryland 20852, United States
| | - Nicholas Rutland
- Section on Medicinal Chemistry, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, 5625 Fishers Lane, Rockville, Maryland 20852, United States
| | - Malliga R Iyer
- Section on Medicinal Chemistry, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, 5625 Fishers Lane, Rockville, Maryland 20852, United States
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5
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Sterol O-Acyltransferase Inhibition Ameliorates High-Fat Diet-Induced Renal Fibrosis and Tertiary Lymphoid Tissue Maturation after Ischemic Reperfusion Injury. Int J Mol Sci 2022; 23:ijms232415465. [PMID: 36555105 PMCID: PMC9779122 DOI: 10.3390/ijms232415465] [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: 10/20/2022] [Revised: 11/30/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022] Open
Abstract
Metabolic syndrome is associated with the development of chronic kidney disease (CKD). We previously demonstrated that aged kidneys are prone to developing tertiary lymphoid tissues (TLTs) and sustain inflammation after injury, leading to CKD progression; however, the relationship between renal TLT and metabolic syndrome is unknown. In this study, we demonstrated that a high-fat diet (HFD) promoted renal TLT formation and inflammation via sterol O-acyltransferase (SOAT) 1-dependent mechanism. Mice fed a HFD prior to ischemic reperfusion injury (IRI) exhibited pronounced renal TLT formation and sustained inflammation compared to the controls. Untargeted lipidomics revealed the increased levels of cholesteryl esters (CEs) in aged kidneys with TLT formation after IRI, and, consistently, the Soat1 gene expression increased. Treatment with avasimibe, a SOAT inhibitor, attenuated TLT maturation and renal inflammation in HFD-fed mice subjected to IRI. Our findings suggest the importance of SOAT1-dependent CE accumulation in the pathophysiology of CKDs associated with TLT.
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6
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Plasma Angiotensin Converting Enzyme 2 (ACE2) Activity in Healthy Controls and Patients with Cardiovascular Risk Factors and/or Disease. J Pers Med 2022; 12:jpm12091495. [PMID: 36143280 PMCID: PMC9501250 DOI: 10.3390/jpm12091495] [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: 08/10/2022] [Revised: 09/05/2022] [Accepted: 09/08/2022] [Indexed: 11/18/2022] Open
Abstract
Angiotensin converting enzyme 2 (ACE2) is an endogenous negative regulator of the renin-angiotensin system, a key factor in the development of cardiovascular disease (CVD). ACE2 is also used by SARS-CoV-2 for host cell entry. Given that COVID-19 is associated with hypercoagulability, it is timely to explore the potential relationship between plasma ACE2 activity and the coagulation profile. In this cross-sectional study, ACE2 activity and global coagulation assays (GCA) including thromboelastography, thrombin, and fibrin generation were measured in adult healthy controls (n = 123; mean age 41 ± 17 years; 35% male) and in patients with cardiovascular risk factors and/or disease (n = 258; mean age 65 ± 14 years; 55% male). ACE2 activity was significantly lower in controls compared to patients with cardiovascular risk factors and/or disease (median 0.10 (0.02, 3.33) vs. 5.99 (1.95, 10.37) pmol/mL/min, p < 0.001). Of the healthy controls, 48% had undetectable ACE2 activity. Controls with detectable ACE2 had lower maximum amplitude (p < 0.001). In patients with cardiovascular risk factors and/or disease, those in the 3rd tertile were older and male (p = 0.002), with a higher Framingham grade and increased number of cardiovascular risk factors (p < 0.001). In conclusion, plasma ACE2 activity is undetectable to very low in young healthy controls with minimal clinically relevant associations to GCA. Patients with cardiovascular risk factors and/or disease have increased plasma ACE2 activity, suggesting that it may be an important biomarker of endothelial dysfunction and atherosclerosis.
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7
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Duan Y, Gong K, Xu S, Zhang F, Meng X, Han J. Regulation of cholesterol homeostasis in health and diseases: from mechanisms to targeted therapeutics. Signal Transduct Target Ther 2022; 7:265. [PMID: 35918332 PMCID: PMC9344793 DOI: 10.1038/s41392-022-01125-5] [Citation(s) in RCA: 66] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 07/04/2022] [Accepted: 07/12/2022] [Indexed: 12/13/2022] Open
Abstract
Disturbed cholesterol homeostasis plays critical roles in the development of multiple diseases, such as cardiovascular diseases (CVD), neurodegenerative diseases and cancers, particularly the CVD in which the accumulation of lipids (mainly the cholesteryl esters) within macrophage/foam cells underneath the endothelial layer drives the formation of atherosclerotic lesions eventually. More and more studies have shown that lowering cholesterol level, especially low-density lipoprotein cholesterol level, protects cardiovascular system and prevents cardiovascular events effectively. Maintaining cholesterol homeostasis is determined by cholesterol biosynthesis, uptake, efflux, transport, storage, utilization, and/or excretion. All the processes should be precisely controlled by the multiple regulatory pathways. Based on the regulation of cholesterol homeostasis, many interventions have been developed to lower cholesterol by inhibiting cholesterol biosynthesis and uptake or enhancing cholesterol utilization and excretion. Herein, we summarize the historical review and research events, the current understandings of the molecular pathways playing key roles in regulating cholesterol homeostasis, and the cholesterol-lowering interventions in clinics or in preclinical studies as well as new cholesterol-lowering targets and their clinical advances. More importantly, we review and discuss the benefits of those interventions for the treatment of multiple diseases including atherosclerotic cardiovascular diseases, obesity, diabetes, nonalcoholic fatty liver disease, cancer, neurodegenerative diseases, osteoporosis and virus infection.
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Affiliation(s)
- Yajun Duan
- Department of Cardiology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.,Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Ke Gong
- Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Suowen Xu
- Department of Cardiology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Feng Zhang
- Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Xianshe Meng
- Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Jihong Han
- Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China. .,College of Life Sciences, Key Laboratory of Bioactive Materials of Ministry of Education, State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, China.
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8
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Griffett K, Hayes M, Bedia-Diaz G, Appourchaux K, Sanders R, Boeckman MP, Koelblen T, Zhang J, Schulman IG, Elgendy B, Burris TP. Antihyperlipidemic Activity of Gut-Restricted LXR Inverse Agonists. ACS Chem Biol 2022; 17:1143-1154. [PMID: 35417135 DOI: 10.1021/acschembio.2c00057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Hyperlipidemia and increased circulating cholesterol levels are associated with increased cardiovascular disease risk. The liver X receptors (LXRs) are regulators of de novo lipogenesis and cholesterol transport and have been validated as potential therapeutic targets for the treatment of atherosclerosis. However, efforts to develop LXR agonists to reduce cardiovascular diseases have failed due to poor clinical outcomes-associated increased hepatic lipogenesis and elevated low-density lipoprotein (LDL) cholesterol (C). Here, we report that LXR inverse agonists are effective in lowering plasma LDL cholesterol and triglycerides in several models of hyperlipidemia, including the Ldlr null mouse model of atherosclerosis. Mechanistic studies demonstrate that LXR directly regulates the expression of Soat2 enzyme in the intestine, which is directly responsible for the re-uptake or excretion of circulating lipids. Oral administration of a gut-specific LXR inverse agonist leads to reduction of Soat2 expression in the intestine and effectively lowers circulating LDL cholesterol and triglyceride levels without modulating LXR target genes in the periphery. In summary, our studies highlight the therapeutic potential of the gut-restricted molecules to treat hyperlipidemia and atherosclerosis through the intestinal LXR-Soat2 axis.
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Affiliation(s)
- Kristine Griffett
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, Alabama 36849, United States
| | - Matthew Hayes
- University of Florida Genetics Institute, Gainesville, Florida 32610, United States
| | - Gonzalo Bedia-Diaz
- Center for Clinical Pharmacology, Washington University School of Medicine and St. Louis College of Pharmacy, St. Louis, Missouri 63110, United States
| | - Kevin Appourchaux
- Center for Clinical Pharmacology, Washington University School of Medicine and St. Louis College of Pharmacy, St. Louis, Missouri 63110, United States
| | - Ryan Sanders
- University of Florida Genetics Institute, Gainesville, Florida 32610, United States
| | - Michael P. Boeckman
- Center for Clinical Pharmacology, Washington University School of Medicine and St. Louis College of Pharmacy, St. Louis, Missouri 63110, United States
| | - Thomas Koelblen
- University of Florida Genetics Institute, Gainesville, Florida 32610, United States
| | - Jinsong Zhang
- Department of Pharmacology & Physiology, Saint Louis University School of Medicine, St. Louis, Missouri 63104, United States
| | - Ira G. Schulman
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, Virginia 22903, United States
| | - Bahaa Elgendy
- Center for Clinical Pharmacology, Washington University School of Medicine and St. Louis College of Pharmacy, St. Louis, Missouri 63110, United States
| | - Thomas P. Burris
- University of Florida Genetics Institute, Gainesville, Florida 32610, United States
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9
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Baumer Y, McCurdy SG, Boisvert WA. Formation and Cellular Impact of Cholesterol Crystals in Health and Disease. Adv Biol (Weinh) 2021; 5:e2100638. [PMID: 34590446 PMCID: PMC11055929 DOI: 10.1002/adbi.202100638] [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: 02/28/2021] [Revised: 08/20/2021] [Indexed: 11/10/2022]
Abstract
Cholesterol crystals (CCs) were first discovered in atherosclerotic plaque tissue in the early 1900 and have since been observed and implicated in many diseases and conditions, including myocardial infarction, abdominal aortic aneurism, kidney disease, ocular diseases, and even central nervous system anomalies. Despite the widespread involvement of CCs in many pathologies, the mechanisms involved in their formation and their role in various diseases are still not fully understood. Current knowledge concerning the formation of CCs, as well as the molecular pathways activated upon cellular exposure to CCs, will be explored in this review. As CC formation is tightly associated with lipid metabolism, the role of cellular lipid homeostasis in the formation of CCs is highlighted, including the role of lysosomes. In addition, cellular pathways and processes known to be affected by CCs are described. In particular, CC-induced activation of the inflammasome and production of reactive oxygen species, along with the role of CCs in complement-mediated inflammation is discussed. Moreover, the clinical manifestation of embolized CCs is described with a focus on renal and skin diseases associated with CC embolism. Lastly, potential therapeutic measures that target either the formation of CCs or their impact on different cell types and tissues are highlighted.
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Affiliation(s)
- Yvonne Baumer
- Social Determinants of Obesity and Cardiovascular Risk Laboratory, National Heart, Lung, and Blood Institute, Building 10, 10 Center Drive, Bethesda, MD 20814, USA
| | - Sara G. McCurdy
- Dept. of Medicine, University of California San Diego, 9500 Gilman Street, La Jolla, CA 92093, USA
| | - William A. Boisvert
- Center for Cardiovascular Research, University of Hawaii, 651 Ilalo Street, Honolulu, HI 96813, USA
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10
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Hai Q, Smith JD. Acyl-Coenzyme A: Cholesterol Acyltransferase (ACAT) in Cholesterol Metabolism: From Its Discovery to Clinical Trials and the Genomics Era. Metabolites 2021; 11:metabo11080543. [PMID: 34436484 PMCID: PMC8398989 DOI: 10.3390/metabo11080543] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/10/2021] [Accepted: 08/12/2021] [Indexed: 11/16/2022] Open
Abstract
The purification and cloning of the acyl-coenzyme A: cholesterol acyltransferase (ACAT) enzymes and the sterol O-acyltransferase (SOAT) genes has opened new areas of interest in cholesterol metabolism given their profound effects on foam cell biology and intestinal lipid absorption. The generation of mouse models deficient in Soat1 or Soat2 confirmed the importance of their gene products on cholesterol esterification and lipoprotein physiology. Although these studies supported clinical trials which used non-selective ACAT inhibitors, these trials did not report benefits, and one showed an increased risk. Early genetic studies have implicated common variants in both genes with human traits, including lipoprotein levels, coronary artery disease, and Alzheimer’s disease; however, modern genome-wide association studies have not replicated these associations. In contrast, the common SOAT1 variants are most reproducibly associated with testosterone levels.
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11
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Duong MT, Nasrallah IM, Wolk DA, Chang CCY, Chang TY. Cholesterol, Atherosclerosis, and APOE in Vascular Contributions to Cognitive Impairment and Dementia (VCID): Potential Mechanisms and Therapy. Front Aging Neurosci 2021; 13:647990. [PMID: 33841127 PMCID: PMC8026881 DOI: 10.3389/fnagi.2021.647990] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 03/08/2021] [Indexed: 12/18/2022] Open
Abstract
Vascular contributions to cognitive impairment and dementia (VCID) are a common cause of cognitive decline, yet limited therapies exist. This cerebrovascular disease results in neurodegeneration via acute, chronic, local, and systemic mechanisms. The etiology of VCID is complex, with a significant impact from atherosclerosis. Risk factors including hypercholesterolemia and hypertension promote intracranial atherosclerotic disease and carotid artery stenosis (CAS), which disrupt cerebral blood flow and trigger ischemic strokes and VCID. Apolipoprotein E (APOE) is a cholesterol and phospholipid carrier present in plasma and various tissues. APOE is implicated in dyslipidemia and Alzheimer disease (AD); however, its connection with VCID is less understood. Few experimental models for VCID exist, so much of the present information has been drawn from clinical studies. Here, we review the literature with a focus on the clinical aspects of atherosclerotic cerebrovascular disease and build a working model for the pathogenesis of VCID. We describe potential intermediate steps in this model, linking cholesterol, atherosclerosis, and APOE with VCID. APOE4 is a minor isoform of APOE that promotes lipid dyshomeostasis in astrocytes and microglia, leading to chronic neuroinflammation. APOE4 disturbs lipid homeostasis in macrophages and smooth muscle cells, thus exacerbating systemic inflammation and promoting atherosclerotic plaque formation. Additionally, APOE4 may contribute to stromal activation of endothelial cells and pericytes that disturb the blood-brain barrier (BBB). These and other risk factors together lead to chronic inflammation, atherosclerosis, VCID, and neurodegeneration. Finally, we discuss potential cholesterol metabolism based approaches for future VCID treatment.
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Affiliation(s)
- Michael Tran Duong
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Ilya M Nasrallah
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - David A Wolk
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | | | - Ta-Yuan Chang
- Geisel School of Medicine, Dartmouth College, Hanover, NH, United States
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12
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Amengual J, Ogando Y, Nikain C, Quezada A, Qian K, Vaisar T, Fisher EA. Short-Term Acyl-CoA:Cholesterol Acyltransferase Inhibition, Combined with Apoprotein A1 Overexpression, Promotes Atherosclerosis Inflammation Resolution in Mice. Mol Pharmacol 2020; 99:175-183. [PMID: 33384285 DOI: 10.1124/molpharm.120.000108] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 12/15/2020] [Indexed: 12/21/2022] Open
Abstract
Acyl-CoA:cholesterol acyltransferase (ACAT) mediates cellular cholesterol esterification. In atherosclerotic plaque macrophages, ACAT promotes cholesteryl ester accumulation, resulting in foam cell formation and atherosclerosis progression. Its complete inactivation in mice, however, showed toxic effects because of an excess of free cholesterol (FC) in macrophages, which can cause endoplasmic reticulum stress, cholesterol crystal formation, and inflammasome activation. Our previous studies showed that long-term partial ACAT inhibition, achieved by dietary supplementation with Fujirebio F1394, delays atherosclerosis progression in apoprotein E-deficient (Apoe -/-) mice by reducing plaque foam cell formation without inflammatory or toxic effects. Here, we determined whether short-term partial inhibition of ACAT, in combination with an enhanced systemic FC acceptor capacity, has synergistic benefits. Thus, we crossbred Apoe -/- with human apoprotein A1-transgenic (APOA1 tg/tg) mice, which have elevated cholesterol-effluxing high-density lipoprotein particles, and subjected Apoe -/- and APOA1 tg/tg/Apoe -/- mice to an atherogenic diet to develop advanced plaques. Then mice were either euthanized (baseline) or fed purified standard diet with or without F1394 for 4 more weeks. Plaques of APOA1 tg/tg/Apoe -/- mice fed F1394 showed a 60% reduction of macrophages accompanied by multiple other benefits, such as reduced inflammation and favorable changes in extracellular composition, in comparison with Apoe -/- baseline mice. In addition, there was no accumulation of cholesterol crystals or signs of toxicity. Overall, these results show that short-term partial ACAT inhibition, coupled to increased cholesterol efflux capacity, favorably remodels atherosclerosis lesions, supporting the potential of these combined therapies in the treatment of advanced atherosclerosis. SIGNIFICANCE STATEMENT: Short-term pharmacological inhibition of acyl-CoA:cholesterol acyltransferase-mediated cholesterol esterification, in combination with increased free cholesterol efflux acceptors, has positive effects in mice by 1) reducing the inflammatory state of the plaque macrophages and 2) favoring compositional changes associated with plaque stabilization. These effects occur without toxicity, showing the potential of these combined therapies in the treatment of advanced atherosclerosis.
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Affiliation(s)
- Jaume Amengual
- Leon H. Charney Division of Cardiology, Department of Medicine, Cardiovascular Research Center, New York University Grossman School of Medicine, New York, New York (J.A., Y.O, C.N., A.Q., K.Q., E.A.F); Department of Food Science and Human Nutrition, University of Illinois Urbana Champaign, Champaign, Illinois (.J.A.); Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, Washington (T.V.); and Division of Biostatistics, Department of Population Health, New York University Grossman School of Medicine, New York, New York (K.Q.)
| | - Yoscar Ogando
- Leon H. Charney Division of Cardiology, Department of Medicine, Cardiovascular Research Center, New York University Grossman School of Medicine, New York, New York (J.A., Y.O, C.N., A.Q., K.Q., E.A.F); Department of Food Science and Human Nutrition, University of Illinois Urbana Champaign, Champaign, Illinois (.J.A.); Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, Washington (T.V.); and Division of Biostatistics, Department of Population Health, New York University Grossman School of Medicine, New York, New York (K.Q.)
| | - Cyrus Nikain
- Leon H. Charney Division of Cardiology, Department of Medicine, Cardiovascular Research Center, New York University Grossman School of Medicine, New York, New York (J.A., Y.O, C.N., A.Q., K.Q., E.A.F); Department of Food Science and Human Nutrition, University of Illinois Urbana Champaign, Champaign, Illinois (.J.A.); Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, Washington (T.V.); and Division of Biostatistics, Department of Population Health, New York University Grossman School of Medicine, New York, New York (K.Q.)
| | - Alexandra Quezada
- Leon H. Charney Division of Cardiology, Department of Medicine, Cardiovascular Research Center, New York University Grossman School of Medicine, New York, New York (J.A., Y.O, C.N., A.Q., K.Q., E.A.F); Department of Food Science and Human Nutrition, University of Illinois Urbana Champaign, Champaign, Illinois (.J.A.); Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, Washington (T.V.); and Division of Biostatistics, Department of Population Health, New York University Grossman School of Medicine, New York, New York (K.Q.)
| | - Kun Qian
- Leon H. Charney Division of Cardiology, Department of Medicine, Cardiovascular Research Center, New York University Grossman School of Medicine, New York, New York (J.A., Y.O, C.N., A.Q., K.Q., E.A.F); Department of Food Science and Human Nutrition, University of Illinois Urbana Champaign, Champaign, Illinois (.J.A.); Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, Washington (T.V.); and Division of Biostatistics, Department of Population Health, New York University Grossman School of Medicine, New York, New York (K.Q.)
| | - Tomas Vaisar
- Leon H. Charney Division of Cardiology, Department of Medicine, Cardiovascular Research Center, New York University Grossman School of Medicine, New York, New York (J.A., Y.O, C.N., A.Q., K.Q., E.A.F); Department of Food Science and Human Nutrition, University of Illinois Urbana Champaign, Champaign, Illinois (.J.A.); Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, Washington (T.V.); and Division of Biostatistics, Department of Population Health, New York University Grossman School of Medicine, New York, New York (K.Q.)
| | - Edward A Fisher
- Leon H. Charney Division of Cardiology, Department of Medicine, Cardiovascular Research Center, New York University Grossman School of Medicine, New York, New York (J.A., Y.O, C.N., A.Q., K.Q., E.A.F); Department of Food Science and Human Nutrition, University of Illinois Urbana Champaign, Champaign, Illinois (.J.A.); Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, Washington (T.V.); and Division of Biostatistics, Department of Population Health, New York University Grossman School of Medicine, New York, New York (K.Q.)
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13
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Neumann B, Chao K, Chang CCY, Chang TY. Nanodisc scaffold peptide (NSP r) replaces detergent by reconstituting acyl-CoA:cholesterol acyltransferase 1 into peptidiscs. Arch Biochem Biophys 2020; 691:108518. [PMID: 32735863 DOI: 10.1016/j.abb.2020.108518] [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] [Received: 05/04/2020] [Revised: 07/20/2020] [Accepted: 07/25/2020] [Indexed: 12/19/2022]
Abstract
To conduct biochemical studies in vitro, membrane proteins (MPs) must be solubilized with detergents. While detergents are great tools, they can also inhibit the biological activity and/or perturb oligomerization of individual MPs. Nanodisc scaffold peptide (NSPr), an amphipathic peptide analog of ApoA1, was recently shown to reconstitute detergent solubilized MPs into peptidiscs in vitro. Acyl-coenzyme A:cholesterol acyltransferase 1 (ACAT1), also known as sterol O-acyltransferase 1 (SOAT1), plays a key role in cellular cholesterol storage in various cell types and is a drug target to treat multiple human diseases. ACAT1 contains nine transmembrane domains (TMDs) and primarily forms a homotetramer in vitro and in intact cells; deletion of the N-terminal dimerization domain produces a homodimer with full retention in catalytic activity. ACAT1 is prone to inactivation by numerous detergents. Here we pursued the use of NSPr to overcome the detergent-induced inactivation of ACAT1 by generating near detergent-free ACAT1 peptidiscs. Based on native-PAGE analysis, we showed that NSPr reconstitutes ACAT1 into soluble peptidiscs, in which ACAT1 exists predominantly in oligomeric states greater than a homotetramer. The formation of these higher-order oligomeric states was independent of the N-terminal dimerization domain, suggesting that the oligomerization is mediated through hydrophobic interactions of multiple ACAT1 subunits. ACAT1 peptidiscs were still susceptible to heat-mediated inactivation, presumably due to the residual detergent (CHAPS) bound to ACAT1. We then conditioned ACAT1 with phosphatidylcholine (PC) to replace CHAPS prior to the formation of ACAT1 peptidiscs. The results showed, when PC was included, ACAT1 was present mainly in higher-order oligomeric states with greater enzymatic activity. With PC present, the enzymatic activity of ACAT1 peptidiscs was protected from heat-mediated inactivation. These results support the use of NSPr to create a near detergent-free solution of ACAT1 in peptidiscs for various in vitro studies. Our current results also raise the possibility that, under certain conditions, ACAT1 may form higher-order oligomeric states in vivo.
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Affiliation(s)
- Bryan Neumann
- Department of Biochemistry & Cell Biology, Geisel School of Medicine, Dartmouth College, Hanover, NH, 03755, USA
| | - Kevin Chao
- College of Medicine, SUNY Downstate Health Sciences University, Brooklyn, NY, 11203, USA
| | - Catherine C Y Chang
- Department of Biochemistry & Cell Biology, Geisel School of Medicine, Dartmouth College, Hanover, NH, 03755, USA.
| | - Ta-Yuan Chang
- Department of Biochemistry & Cell Biology, Geisel School of Medicine, Dartmouth College, Hanover, NH, 03755, USA.
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14
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Hill J, Shao X, Wright JS, Stauff J, Sherman PS, Arteaga J, Wong KK, Viglianti BL, Scott PJH, Brooks AF. Synthesis and Evaluation of 11C- and 18F-Labeled SOAT1 Inhibitors as Macrophage Foam Cell Imaging Agents. ACS Med Chem Lett 2020; 11:1299-1304. [PMID: 32551015 PMCID: PMC7294710 DOI: 10.1021/acsmedchemlett.0c00127] [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: 03/11/2020] [Accepted: 04/30/2020] [Indexed: 11/30/2022] Open
Abstract
PD-132301, an inhibitor of sterol O-acyltransferase 1 (SOAT1; also known as acyl-coenzyme A:cholesterol acyltransferase-1, ACAT1), is under clinical investigation for numerous adrenal disorders. Radiolabeled SOAT1 inhibitors could support drug discovery and help diagnose SOAT1-related disorders, such as atherosclerosis. We synthesized two radiolabeled SOAT1 inhibitors, [11C]PD-132301 and fluorine analogue [18F]1. Rat biodistribution studies were conducted with both agents and, as the most selective tracer, [11C]PD-132301 was advanced to preclinical positron emission tomography studies in (atherosclerotic) ApoE-/- mice. The uptake of [11C]PD-132301 in SOAT1-rich tissue warrants further investigation into the compound as an atherosclerosis and adrenal imaging agent.
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Affiliation(s)
- James
R. Hill
- Institute
for Molecular Bioscience, The University
of Queensland, Brisbane, Queensland 4072, Australia
- Department
of Radiology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Xia Shao
- Department
of Radiology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jay S. Wright
- Department
of Radiology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jenelle Stauff
- Department
of Radiology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Phillip S. Sherman
- Department
of Radiology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Janna Arteaga
- Department
of Radiology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Ka Kit Wong
- Department
of Radiology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Benjamin L. Viglianti
- Department
of Radiology, University of Michigan, Ann Arbor, Michigan 48109, United States
- Nuclear
Medicine Service, Veterans Administration, Ann Arbor, Michigan 48105, United States
| | - Peter J. H. Scott
- Department
of Radiology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Allen F. Brooks
- Department
of Radiology, University of Michigan, Ann Arbor, Michigan 48109, United States
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15
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Zhang Y, Jian W, He L, Wu J. Externalized histone H4: a novel target that orchestrates chronic inflammation by inducing lytic cell death. Acta Biochim Biophys Sin (Shanghai) 2020; 52:336-338. [PMID: 32072162 DOI: 10.1093/abbs/gmz165] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 11/09/2018] [Accepted: 12/05/2018] [Indexed: 11/15/2022] Open
Affiliation(s)
- Yao Zhang
- Department of Inspection, The First People’s Hospital of Changde City, Changde 415003, China, and
| | - Wu Jian
- Department of Inspection, The First People’s Hospital of Changde City, Changde 415003, China, and
| | - Lu He
- Department of Neurosurgery, The First Affiliated Hospital, University of South China, Hengyang 421001, China
| | - Jianhua Wu
- Department of Inspection, The First People’s Hospital of Changde City, Changde 415003, China, and
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16
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Mechanisms and regulation of cholesterol homeostasis. Nat Rev Mol Cell Biol 2019; 21:225-245. [DOI: 10.1038/s41580-019-0190-7] [Citation(s) in RCA: 450] [Impact Index Per Article: 90.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2019] [Indexed: 12/14/2022]
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