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Gissler MC, Scherrer P, Anto-Michel N, Pennig J, Hoppe N, Füner L, Härdtner C, Stachon P, Li X, Mitre LS, Marchini T, Madl J, Wadle C, Hilgendorf I, von Zur Mühlen C, Bode C, Weber C, Lutgens E, Wolf D, Gerdes N, Zirlik A, Willecke F. Deficiency of Endothelial CD40 Induces a Stable Plaque Phenotype and Limits Inflammatory Cell Recruitment to Atherosclerotic Lesions in Mice. Thromb Haemost 2021; 121:1530-1540. [PMID: 33618394 DOI: 10.1055/a-1397-1858] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVES The co-stimulatory CD40L-CD40 dyad exerts a critical role in atherosclerosis by modulating leukocyte accumulation into developing atherosclerotic plaques. The requirement for cell-type specific expression of both molecules, however, remains elusive. Here, we evaluate the contribution of CD40 expressed on endothelial cells (ECs) in a mouse model of atherosclerosis. METHODS AND RESULTS Atherosclerotic plaques of apolipoprotein E-deficient (Apoe -/- ) mice and humans displayed increased expression of CD40 on ECs compared with controls. To interrogate the role of CD40 on ECs in atherosclerosis, we induced EC-specific (BmxCreERT2-driven) deficiency of CD40 in Apoe -/- mice. After feeding a chow diet for 25 weeks, EC-specific deletion of CD40 (iEC-CD40) ameliorated plaque lipid deposition and lesional macrophage accumulation but increased intimal smooth muscle cell and collagen content, while atherosclerotic lesion size did not change. Leukocyte adhesion to the vessel wall was impaired in iEC-CD40-deficient mice as demonstrated by intravital microscopy. In accord, expression of vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1) in the vascular endothelium declined after deletion of CD40. In vitro, antibody-mediated inhibition of human endothelial CD40 significantly abated monocyte adhesion on ECs. CONCLUSION Endothelial deficiency of CD40 in mice promotes structural features associated with a stable plaque phenotype in humans and decreases leukocyte adhesion. These results suggest that endothelial-expressed CD40 contributes to inflammatory cell migration and consecutive plaque formation in atherogenesis.
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Affiliation(s)
- Mark Colin Gissler
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Philipp Scherrer
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Nathaly Anto-Michel
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jan Pennig
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Natalie Hoppe
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Lisa Füner
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Carmen Härdtner
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Peter Stachon
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Xiaowei Li
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Lucia Sol Mitre
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Timoteo Marchini
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Josef Madl
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Germany
| | - Carolin Wadle
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ingo Hilgendorf
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Constantin von Zur Mühlen
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christoph Bode
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christian Weber
- Institute for Cardiovascular Prevention, Ludwig-Maximilians-University, Munich, Germany
- German Center for Cardiovascular Research, Partner Site Munich Heart Alliance, Munich, Germany
- Department of Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands
| | - Esther Lutgens
- Institute for Cardiovascular Prevention, Ludwig-Maximilians-University, Munich, Germany
- German Center for Cardiovascular Research, Partner Site Munich Heart Alliance, Munich, Germany
- Department of Medical Biochemistry, University of Amsterdam, Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Dennis Wolf
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Norbert Gerdes
- Division of Cardiology, Pulmonology, and Vascular Medicine, Medical Faculty, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Andreas Zirlik
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Division of Cardiology, Medical University of Graz, Graz, Austria
| | - Florian Willecke
- Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Klinik für Allgemeine und Interventionelle Kardiologie/Angiologie, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bochum, Germany
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Gissler MC, Anto-Michel N, Pennig J, Scherrer P, Li X, Marchini T, Pfeiffer K, Härdtner C, Abogunloko T, Mwinyella T, Sol Mitre L, Spiga L, Koentges C, Smolka C, von Elverfeldt D, Hoppe N, Stachon P, Dufner B, Heidt T, Piepenburg S, Hilgendorf I, Bjune JI, Dankel SN, Mellgren G, Seifert G, Eisenhardt SU, Bugger H, von Zur Muhlen C, Bode C, Zirlik A, Wolf D, Willecke F. Genetic Deficiency of TRAF5 Promotes Adipose Tissue Inflammation and Aggravates Diet-Induced Obesity in Mice. Arterioscler Thromb Vasc Biol 2021; 41:2563-2574. [PMID: 34348490 DOI: 10.1161/atvbaha.121.316677] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective: The accumulation of inflammatory leukocytes is a prerequisite of adipose tissue inflammation during cardiometabolic disease. We previously reported that a genetic deficiency of the intracellular signaling adaptor TRAF5 (TNF [tumor necrosis factor] receptor-associated factor 5) accelerates atherosclerosis in mice by increasing inflammatory cell recruitment. Here, we tested the hypothesis that an impairment of TRAF5 signaling modulates adipose tissue inflammation and its metabolic complications in a model of diet-induced obesity in mice. Approach and Results: To induce diet-induced obesity and adipose tissue inflammation, wild-type or Traf5-/- mice consumed a high-fat diet for 18 weeks. Traf5-/- mice showed an increased weight gain, impaired insulin tolerance, and increased fasting blood glucose. Weight of livers and peripheral fat pads was increased in Traf5-/- mice, whereas lean tissue weight and growth were not affected. Flow cytometry of the stromal vascular fraction of visceral adipose tissue from Traf5-/- mice revealed an increase in cytotoxic T cells, CD11c+ macrophages, and increased gene expression of proinflammatory cytokines and chemokines. At the level of cell types, expression of TNF[alpha], MIP (macrophage inflammatory protein)-1[alpha], MCP (monocyte chemoattractant protein)-1, and RANTES (regulated on activation, normal T-cell expressed and secreted) was significantly upregulated in Traf5-deficient adipocytes but not in Traf5-deficient leukocytes from visceral adipose tissue. Finally, Traf5 expression was lower in adipocytes from obese patients and mice and recovered in adipose tissue of obese patients one year after bariatric surgery. Conclusions: We show that a genetic deficiency of TRAF5 in mice aggravates diet-induced obesity and its metabolic derangements by a proinflammatory response in adipocytes. Our data indicate that TRAF5 may promote anti-inflammatory and obesity-preventing signaling events in adipose tissue.
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Affiliation(s)
- Mark Colin Gissler
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Nathaly Anto-Michel
- Department of Cardiology, Medical University of Graz, Austria (N.A.M., H.B., A.Z.)
| | - Jan Pennig
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Philipp Scherrer
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Xiaowei Li
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Timoteo Marchini
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Katharina Pfeiffer
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Carmen Härdtner
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Tijani Abogunloko
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Timothy Mwinyella
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Lucia Sol Mitre
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Lisa Spiga
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Christoph Koentges
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
- Institute of Neuropathology (C.K.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany
| | - Christian Smolka
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Dominik von Elverfeldt
- Department of Radiology, Medical Physics (D.v.E.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany
| | - Natalie Hoppe
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Peter Stachon
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Bianca Dufner
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Timo Heidt
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Sven Piepenburg
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Ingo Hilgendorf
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Jan-Inge Bjune
- Center for Diabetes Research (J.-I.B., S.N.D., G.M.), University of Bergen, Norway
- Mohn Nutrition Research Laboratory, Department of Clinical Science (J.-I.B., S.N.D., G.M.), University of Bergen, Norway
- Hormone Laboratory, Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway (J.-I.B., S.N.D., G.M.)
| | - Simon N Dankel
- Center for Diabetes Research (J.-I.B., S.N.D., G.M.), University of Bergen, Norway
- Mohn Nutrition Research Laboratory, Department of Clinical Science (J.-I.B., S.N.D., G.M.), University of Bergen, Norway
- Hormone Laboratory, Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway (J.-I.B., S.N.D., G.M.)
| | - Gunnar Mellgren
- Center for Diabetes Research (J.-I.B., S.N.D., G.M.), University of Bergen, Norway
- Mohn Nutrition Research Laboratory, Department of Clinical Science (J.-I.B., S.N.D., G.M.), University of Bergen, Norway
- Hormone Laboratory, Department of Medical Biochemistry and Pharmacology, Haukeland University Hospital, Bergen, Norway (J.-I.B., S.N.D., G.M.)
| | - Gabriel Seifert
- Department of General and Visceral Surgery (G.S.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany
| | - Steffen U Eisenhardt
- Department of Plastic and Hand Surgery, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Breisgau, Germany (S.U.E.)
| | - Heiko Bugger
- Department of Cardiology, Medical University of Graz, Austria (N.A.M., H.B., A.Z.)
| | - Constantin von Zur Muhlen
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Christoph Bode
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Andreas Zirlik
- Department of Cardiology, Medical University of Graz, Austria (N.A.M., H.B., A.Z.)
| | - Dennis Wolf
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
| | - Florian Willecke
- Cardiology and Angiology I, University Heart Center, Faculty of Medicine, University of Freiburg, Germany (M.C.G., J.P., P.S., X.L., T. Marchini, K.P., C.H., T.A., T. Mwinyella, L.S.M., L.S., C.K., C.S., N.H., P.S., B.D., T.H., S.P., I.H., C.v.z.M., C.B., D.W., F.W.)
- Clinic for General and Interventional Cardiology/Angiology, Herz- und Diabeteszentrum NRW, Ruhr-Universität Bochum, Bad Oeynhausen, Germany (F.W.)
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Pennig J, Scherrer P, Gissler MC, Anto-Michel N, Hoppe N, Füner L, Härdtner C, Stachon P, Wolf D, Hilgendorf I, Mullick A, Bode C, Zirlik A, Goldberg IJ, Willecke F. Glucose lowering by SGLT2-inhibitor empagliflozin accelerates atherosclerosis regression in hyperglycemic STZ-diabetic mice. Sci Rep 2019; 9:17937. [PMID: 31784656 PMCID: PMC6884628 DOI: 10.1038/s41598-019-54224-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 10/26/2019] [Indexed: 12/12/2022] Open
Abstract
Diabetes worsens atherosclerosis progression and leads to a defect in repair of arteries after cholesterol reduction, a process termed regression. Empagliflozin reduces blood glucose levels via inhibition of the sodium glucose cotransporter 2 (SGLT-2) in the kidney and has been shown to lead to a marked reduction in cardiovascular events in humans. To determine whether glucose lowering by empagliflozin accelerates atherosclerosis regression in a mouse model, male C57BL/6J mice were treated intraperitoneally with LDLR- and SRB1- antisense oligonucleotides and fed a high cholesterol diet for 16 weeks to induce severe hypercholesterolemia and atherosclerosis progression. At week 14 all mice were rendered diabetic by streptozotocin (STZ) injections. At week 16 a baseline group was sacrificed and displayed substantial atherosclerosis of the aortic root. In the remaining mice, plasma cholesterol was lowered by switching to chow diet and treatment with LDLR sense oligonucleotides to induce atherosclerosis regression. These mice then received either empagliflozin or vehicle for three weeks. Atherosclerotic plaques in the empagliflozin treated mice were significantly smaller, showed decreased lipid and CD68+ macrophage content, as well as greater collagen content. Proliferation of plaque resident macrophages and leukocyte adhesion to the vascular wall were significantly decreased in empagliflozin-treated mice. In summary, plasma glucose lowering by empagliflozin improves plaque regression in diabetic mice.
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Affiliation(s)
- Jan Pennig
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany
| | - Philipp Scherrer
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany
| | - Mark Colin Gissler
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany
| | - Nathaly Anto-Michel
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany
| | - Natalie Hoppe
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany
| | - Lisa Füner
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany
| | - Carmen Härdtner
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany
| | - Peter Stachon
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany
| | - Dennis Wolf
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany
| | - Ingo Hilgendorf
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany
| | - Adam Mullick
- Ionis Pharmaceuticals, Carlsbad, California, USA
| | - Christoph Bode
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany
| | - Andreas Zirlik
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany.,Division of Cardiology, Medical University of Graz, Graz, Austria
| | - Ira J Goldberg
- Department of Medicine, New York University Langone Health, New York, NY, USA
| | - Florian Willecke
- University Heart Center Freiburg-Bad Krozingen, Cardiology and Angiology I, University of Freiburg, Freiburg, Germany. .,Klinik für Allgemeine und Interventionelle Kardiologie/Angiologie, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bochum, Germany.
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Gissler MC, Anto Michel N, Pennig J, Scherrer P, Pfeiffer K, Haerdtner C, Von Elverfeldt D, Hoppe N, Stachon P, Machulsky N, Hilgendorf I, Bode C, Wolf D, Zirlik A, Willecke F. P1939Tumor necrosis factor receptor-associated factor 5 (TRAF-5) deficiency exacerbates diet-induced adipose tissue inflammation and aggravates metabolic syndrome in mice. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Introduction
Many clinical and experimental observations have established an association between visceral obesity and chronic adipose tissue inflammation. Potent pro-inflammatory mediators such as TNFα, CD40 and IL-1β are regulated by Tumor necrosis factor (TNF) receptor-associated factors (TRAFs). TRAF5 deficiency accelerates atherogenesis in mice by increasing inflammatory leukocyte recruitment. Since inflammatory cell invasion is also a prerequisite of adipose tissue inflammation, we tested the hypothesis that deficient TRAF5 signaling aggravates adipose tissue inflammation and its metabolic complications in a murine diet-induced obesity (DIO) model.
Purpose
We aimed to clarify the role of TRAF5 in adipose tissue inflammation and metabolic syndrome.
Methods
TRAF5−/− mice and gender- and age-matched wild-type (WT) mice consumed a high fat diet (HFD, 45%kcal from fat) or a matched low-fat diet (LFD, 10%kcal from fat) for 18 weeks to induce DIO and adipose tissue inflammation. All mice were then subjected to subsequent analysis, including glucose and insulin tolerance testing, body composition assessment by MRI imaging, flow cytometry, gene expression of different tissues, plasma analysis and histology. Finally, we studied if TRAF5 expression was associated with metabolic syndrome in humans by analyzing plasma and adipocytes samples from 62 patients of the Tumor-Necrosis-Factor Receptor Associated in Cardiovascular Risk Study (TRAFICS).
Results
TRAF5 expression was significantly attenuated in isolated WT-adipocytes and WT-macrophages after 18 weeks of HFD compared to LFD-fed controls. TRAF5−/− mice on HFD gained significantly more weight compared to TRAF5-competent mice and showed an aggravated metabolic phenotype, including impaired insulin tolerance, hyperinsulinemia and increased fasting glucose plasma levels. The weight gain in TRAF5−/− mice was attributable to a significant increase in adipose tissue and liver weight. Further analysis of the visceral adipose tissue revealed enhanced macrophage accumulation and increased pro-inflammatory CD11c+ subset polarization in HFD-fed TRAF5−/− mice. In line with an increased migratory capacity of inflammatory cells, we observed enhanced peritoneal invasion of leukocytes and subsets in TRAF5−/− mice. Accordingly, TRAF5 deficiency increased inflammatory cytokine expression and ameliorated parameters of insulin sensitivity in adipose tissue. Finally, patients with metabolic syndrome displayed decreased TRAF5 expression in blood and adipocytes compared to humans without metabolic syndrome.
Conclusion
We show that genetic deficiency of TRAF5 aggravates metabolic syndrome in murine diet-induced obesity. Enhanced accumulation of leukocytes subsets in adipose tissue serves as the likely mechanism. We conclude that TRAF5 signaling properties may favorably affect metabolic disease.
Acknowledgement/Funding
Forschungskommission Medizinische Fakultät Universität Freiburg, MOTI-VATE Promotionskolleg der Medizinischen Fakultät Freiburg (EKFS)
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Affiliation(s)
- M C Gissler
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - N Anto Michel
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - J Pennig
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - P Scherrer
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - K Pfeiffer
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - C Haerdtner
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - D Von Elverfeldt
- University of Freiburg, Department of Radiology, Medical Physics, Freiburg, Germany
| | - N Hoppe
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - P Stachon
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - N Machulsky
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - I Hilgendorf
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - C Bode
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - D Wolf
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
| | - A Zirlik
- Medical University of Graz, Department of Cardiology, Graz, Austria
| | - F Willecke
- University of Freiburg, Faculty of Medicine, Heart Center Freiburg University, Department of Cardiology and Angiology I, Freiburg, Germany
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5
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7
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Scherrer P, Blasco F, Imbert D. Etude experimentalein situde la toxicite du petrole brut et de 2 additifs envers les plantules deRhizophora mangle. ACTA ACUST UNITED AC 2008. [DOI: 10.1080/09593338909384747] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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8
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Affiliation(s)
- A Mordi
- Service de Chirurgie Viscérale et Gynécologique, Centre Hospitalier Général - Decize.
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9
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10
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Abstract
Nitration of tyrosine-26 at pH 9.0 in bacteriorhodopsin does not change its absorption spectrum but lowers the apparent pK of the alkaline transition to a blue-shifted chromophore from about pH 12.0 to 10.6. This effect is reversed by reducing the nitrotyrosine-26 to aminotyrosine which demonstrates that the protonation state of tyrosine-26 and the alkaline chromophore transition are correlated. Nitration of tyrosine-64 resulted in a shift of the purple complex from 570 to 535 nm at neutral pH. The alkaline transition pK of such a nitrated membrane was below 10 but was clearly independent of the protonation state of tyrosine-64 because it is not reversed by reduction of the nitrotyrosine. Nitrotyrosine-26 showed spectral properties similar to L-nitrotyrosine in aqueous environment while nitrotyrosine-64 showed only a 360-nm absorbance in the apomembrane but not in the retinal-containing membrane. Both tyrosines are accessible to water-soluble reagents.
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11
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Abstract
The interaction of the synthetic 21 amino acid peptide (AcE4K) with 1-oleoyl-2-[caproyl-7-NBD]-sn-glycero-3-phosphocholine membranes is used as a model system for the pH-sensitive binding of fusion peptides to membranes. The sequence of AcE4K (Ac-GLFEAIAGFIENGWEGMIDGK) is based on the sequence of the hemagglutinin HA2 fusion peptide and has similar partitioning into phosphatidylcholine membranes as the viral peptide. pH-dependent partitioning in the membrane, circular dichroism, tryptophan fluorescence, change of membrane area, and membrane strength, are measured to characterize various key aspects of the peptide-membrane interaction. The experimental results show that the partitioning of AcE4K in the membrane is pH dependent. The bound peptide inserts in the membrane, which increases the overall membrane area in a pH-dependent manner, however the depth of insertion of the peptide in the membrane is independent of pH. This result suggests that the binding of the peptide to the membrane is driven by the protonation of its three glutamatic acids and the aspartic acid, which results in an increase of the number of bound molecules as the pH decreases from pH 7 to 4.5. The transition between the bound state and the free state is characterized by the Gibbs energy for peptide binding. This Gibbs energy for pH 5 is equal to -30.2 kJ/mol (-7.2 kcal/mol). Most of the change of the Gibbs energy during the binding of AcE4K is due to the enthalpy of binding -27.3 kJ/mol (-6.5 kcal/mol), while the entropy change is relatively small and is on the order of 6.4 J/mol.K (2.3 cal/mol.K). The energy barrier separating the bound and the free state, is characterized by the Gibbs energy of the transition state for peptide adsorption. This Gibbs energy is equal to 51.3 kJ/mol (12.3 kcal/mol). The insertion of the peptide into the membrane is coupled with work for creation of a vacancy for the peptide in the membrane. This work is calculated from the measured area occupied by a single peptide molecule (220 A(2)) and the membrane elasticity (190 mN/m), and is equal to 15.5 kJ/mol (3.7 kcal/mol). The comparison of the work for creating a vacancy and the Gibbs energy of the transition state shows that the work for creating a vacancy may have significant effect on the rate of peptide insertion and therefore plays an important role in peptide binding. Because the work for creating a vacancy depends on membrane elasticity and the elasticity of the membrane is dependent on membrane composition, this provides a tool for modulating the pH for membrane instability by changing membrane composition. The insertion of the peptide in the membrane does not affect the membrane permeability for water, which shows that the peptide does not perturb substantially the packing of the hydrocarbon region. However, the ability of the membrane to retain solutes in the presence of peptide is compromised, suggesting that the inserted peptide promotes formation of short living pores. The integrity of the membrane is substantially compromised below pH 4.8 (threshold pH), when large pores are formed and the membrane breaks down. The binding of the peptide in the pore region is reversible, and the pore size varies on the experimental conditions, which suggests that the peptide in the pore region does not form oligomers.
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Affiliation(s)
- D V Zhelev
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708-0300, USA.
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12
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Maurer N, Wong KF, Stark H, Louie L, McIntosh D, Wong T, Scherrer P, Semple SC, Cullis PR. Spontaneous entrapment of polynucleotides upon electrostatic interaction with ethanol-destabilized cationic liposomes. Biophys J 2001; 80:2310-26. [PMID: 11325732 PMCID: PMC1301421 DOI: 10.1016/s0006-3495(01)76202-9] [Citation(s) in RCA: 168] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
This study describes the effect of ethanol and the presence of poly(ethylene) glycol (PEG) lipids on the interaction of nucleotide-based polyelectrolytes with cationic liposomes. It is shown that preformed large unilamellar vesicles (LUVs) containing a cationic lipid and a PEG coating can be induced to entrap polynucleotides such as antisense oligonucleotides and plasmid DNA in the presence of ethanol. The interaction of the cationic liposomes with the polynucleotides leads to the formation of multilamellar liposomes ranging in size from 70 to 120 nm, only slightly bigger than the parent LUVs from which they originated. The degree of lamellarity as well as the size and polydispersity of the liposomes formed increases with increasing polynucleotide-to-lipid ratio. A direct correlation between the entrapment efficiency and the membrane-destabilizing effect of ethanol was observed. Although the morphology of the liposomes is still preserved at the ethanol concentrations used for entrapment (25-40%, v/v), entrapped low-molecular-weight solutes leak rapidly. In addition, lipids can flip-flop across the membrane and exchange rapidly between liposomes. Furthermore, there are indications that the interaction of the polynucleotides with the cationic liposomes in ethanol leads to formation of polynucleotide-cationic lipid domains, which act as adhesion points between liposomes. It is suggested that the spreading of this contact area leads to expulsion of PEG-ceramide and triggers processes that result in the formation of multilamellar systems with internalized polynucleotides. The high entrapment efficiencies achieved at high polyelectrolyte-to-lipid ratios and the small size and neutral character of these novel liposomal systems are of utility for liposomal delivery of macromolecular drugs.
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Affiliation(s)
- N Maurer
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.
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13
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Semple SC, Klimuk SK, Harasym TO, Dos Santos N, Ansell SM, Wong KF, Maurer N, Stark H, Cullis PR, Hope MJ, Scherrer P. Efficient encapsulation of antisense oligonucleotides in lipid vesicles using ionizable aminolipids: formation of novel small multilamellar vesicle structures. Biochim Biophys Acta 2001; 1510:152-66. [PMID: 11342155 DOI: 10.1016/s0005-2736(00)00343-6] [Citation(s) in RCA: 282] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Typical methods used for encapsulating antisense oligodeoxynucleotides (ODN) and plasmid DNA in lipid vesicles result in very low encapsulation efficiencies or employ cationic lipids that exhibit unfavorable pharmacokinetic and toxicity characteristics when administered intravenously. In this study, we describe and characterize a novel formulation process that utilizes an ionizable aminolipid (1,2-dioleoyl-3-dimethylammonium propane, DODAP) and an ethanol-containing buffer system for encapsulating large quantities (0.15--0.25 g ODN/g lipid) of polyanionic ODN in lipid vesicles. This process requires the presence of up to 40% ethanol (v/v) and initial formulation at acidic pH values where the DODAP is positively charged. In addition, the presence of a poly(ethylene glycol)-lipid was required during the formulation process to prevent aggregation. The 'stabilized antisense-lipid particles' (SALP) formed are stable on adjustment of the external pH to neutral pH values and the formulation process allows encapsulation efficiencies of up to 70%. ODN encapsulation was confirmed by nuclease protection assays and (31)P NMR measurements. Cryo-electron microscopy indicated that the final particles consisted of a mixed population of unilamellar and small multilamellar vesicles (80--140 nm diameter), the relative proportion of which was dependent on the initial ODN to lipid ratio. Finally, SALP exhibited significantly enhanced circulation lifetimes in mice relative to free antisense ODN, cationic lipid/ODN complexes and SALP prepared with quaternary aminolipids. Given the small particle sizes and improved encapsulation efficiency, ODN to lipid ratios, and circulation times of this formulation compared to others, we believe SALP represent a viable candidate for systemic applications involving nucleic acid therapeutics.
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Affiliation(s)
- S C Semple
- Inex Pharmaceutical Corp., Burnaby, B.C., Canada.
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14
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Tam P, Monck M, Lee D, Ludkovski O, Leng EC, Clow K, Stark H, Scherrer P, Graham RW, Cullis PR. Stabilized plasmid-lipid particles for systemic gene therapy. Gene Ther 2000; 7:1867-74. [PMID: 11110420 DOI: 10.1038/sj.gt.3301308] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The structure of 'stabilized plasmid-lipid particles' (SPLP) and their properties as systemic gene therapy vectors has been investigated. We show that SPLP can be visualized employing cryo-electron microscopy to be homogeneous particles of diameter 72 +/- 5 nm consisting of a lipid bilayer surrounding a core of plasmid DNA. It is also shown that SPLP exhibit long circulation lifetimes (circulation half-life >6 h) following intravenous (i.v.) injection in a murine tumor model resulting in accumulation of up to 3% of the total injected dose and concomitant reporter gene expression at a distal (hind flank) tumor site. In contrast, i v. injection of naked plasmid DNA or plasmid DNA-cationic liposome complexes did not result in significant plasmid delivery to the tumor site or gene expression at that site. Furthermore, it is shown that high doses of SPLP corresponding to 175 microg plasmid per mouse are nontoxic as assayed by monitoring serum enzyme levels, whereas i.v. injection of complexes give rise to significant toxicity at dose levels above 20 microg plasmid per mouse. It is concluded that SPLP exhibit properties consistent with potential utility as a nontoxic systemic gene therapy vector.
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Affiliation(s)
- P Tam
- Inex Pharmaceuticals Corporation, Burnaby, BC, Canada
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15
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Saravolac EG, Ludkovski O, Skirrow R, Ossanlou M, Zhang YP, Giesbrecht C, Thompson J, Thomas S, Stark H, Cullis PR, Scherrer P. Encapsulation of plasmid DNA in stabilized plasmid-lipid particles composed of different cationic lipid concentration for optimal transfection activity. J Drug Target 2000; 7:423-37. [PMID: 10758913 DOI: 10.3109/10611860009102217] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
In previous work (Wheeler et al. (1999) Gene Therapy 6, 271-281) we have shown that plasmid DNA can be entrapped in "stabilized plasmid lipid particles" (SPLP) using low levels (5-10 mol%) of cationic lipid, the fusogenic lipid dioleoylphosphatidylethanolamine (DOPE), and a polyethyleneglycol (PEG) coating for stabilization. The PEG moieties are attached to a ceramide anchor containing an arachidoyl acyl group (PEG-CerC20). However, these SPLP exhibit low transfection potencies in vitro as compared to plasmid/cationic lipid complexes formed with liposomes composed of cationic and neutral lipid at a 1:1 lipid ratio. The objective of this study was to construct SPLPs with increased cationic lipid contents that result in maximum transfection levels. A phosphate buffer detergent dialysis technique is described resulting in formation of SPLP containing 7-42.5 mol% DODAC with reproducible encapsulation efficiency of up to 80%. An octanoyl acyl group was used as anchor for the PEG moiety (PEG-CerC8) permitting a quick exchange out of the SPLP to further optimize the in vitro and in vivo transfection. We have demonstrated that this technique can be used to encapsulate either linearized DNA or supercoiled plasmids ranging from 3-20 kb. The SPLP formed could be isolated from empty vesicles by sucrose density gradient centrifugation, and exhibited a narrow size distribution of approximately 75 +/- 6 nm as determined by cryo-electron microscopy. The high plasmid-to-lipid ratio observed corresponded to one plasmid per particle. The SPLP consist of a lipid bilayer surrounding the plasmid DNA as visualized by cryo-electron microscopy. SPLP containing a range of DODAC concentrations were tested for in vitro and in vivo transfection. In vitro, in COS-7 cells transfection reached a maximum after 48 h. The transfection efficiency increased when the DODAC concentration in the SPLP was decreased from 42.5 to 24 mol% DODAC. Decreasing the cationic lipid concentration improved transfection in part due to decreased toxicity. In vivo studies using an intraperitoneal B16 tumor model and intraperitoneal administration of SPLP showed maximum transfection activity for SPLP containing 24 mol% DODAC. Gene expression observed in tumor cells was increased by approximately one magnitude as compared to cationic lipid/DNA complexes. The SPLP were stable and upon storage at 4 degrees C no significant change in the transfection activity was observed over a one-year period. Thus this phosphate buffer detergent dialysis technique can be used to generate SPLP formulations containing a wide range of cationic lipid concentrations to determine optimal SPLP composition for high transfection activity and low toxicity.
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16
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Monck MA, Mori A, Lee D, Tam P, Wheeler JJ, Cullis PR, Scherrer P. Stabilized plasmid-lipid particles: pharmacokinetics and plasmid delivery to distal tumors following intravenous injection. J Drug Target 2000; 7:439-52. [PMID: 10758914 DOI: 10.3109/10611860009102218] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A previous study has shown that plasmid DNA can be encapsulated in lipid particles (SPLP, "stabilized plasmid lipid particles") of approximately 70 nm diameter composed of 1,2-dioleoyl-3-phosphatidyl-ethanolamine (DOPE), the cationic lipid N,N-dioleoyl-N,N-dimethylammonium chloride (DODAC) and poly(ethylene glycol) conjugated to ceramide (PEG-Cer) using a detergent dialysis process (Wheeler et al. (1999) Gene Therapy 6, 271-281). In this work we evaluated the potential of these SPLPs as systemic gene therapy vectors, determining their pharmacokinetics and the biodistribution of the plasmid and lipid components. It is shown that the blood clearance and the biodistribution of the SPLPs can be modulated by varying the acyl chain length of the ceramide group used as lipid anchor for the PEG polymer. Circulation lifetimes observed for SPLPs with PEG-CerC14 and PEG-CerC20 were t(1/2) = approximately 1 and approximately 10 h, respectively. The SPLPs are stable while circulating in the blood and the encapsulated DNA is fully protected from degradation by serum nucleases. The accelerated clearance of SPLPs with PEG-CerC14 is accompanied by increased accumulation in liver and spleen as compared to PEG-CerC20 SPLPs. Delivery of intact plasmid to liver and spleen was detected. Significant accumulation (approximately 10% of injected dose) of the long circulating SPLPs with PEG-CerC20 in a distal tumor (Lewis lung tumor in the mouse flank) was observed following i.v. application and delivery of intact plasmid to tumor tissue at approximately 6% injected dose/g tissue is demonstrated.
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Affiliation(s)
- M A Monck
- Inex Pharmaceuticals Corporation, Burnaby, BC, Canada
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17
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Klimuk SK, Semple SC, Nahirney PN, Mullen MC, Bennett CF, Scherrer P, Hope MJ. Enhanced anti-inflammatory activity of a liposomal intercellular adhesion molecule-1 antisense oligodeoxynucleotide in an acute model of contact hypersensitivity. J Pharmacol Exp Ther 2000; 292:480-8. [PMID: 10640283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
The anti-inflammatory activity of free and liposome-encapsulated oligonucleotide targeted against intercellular adhesion molecule-1 mRNA was investigated in a delayed type hypersensitivity model of acute inflammation in mice. Contact hypersensitivity reactions to 2, 4-dinitrofluorobenzene were monitored by measuring ear thickness and cellular infiltration, both of which were observed to be maximal 24 h after ear challenge. A murine-specific phosphorothioate oligodeoxynucleotide and various control sequences were each passively encapsulated into 100-nm diameter large unilamellar vesicles composed of egg phosphatidylcholine and cholesterol. All formulations were administered as a single-bolus injection into the tail vein approximately 15 min after initiating ear inflammation. Oligodeoxynucleotide dose was varied from 5 to 50 mg/kg and the extent of inflammation was assessed 24 h later. Mice treated with free oligonucleotide, empty vesicles, or encapsulated control sequences showed no measurable effect on ear swelling or cellular infiltration compared with untreated controls. However, mice that received the active sequence encapsulated in lipid vesicles exhibited near baseline levels of ear thickness and leukocyte infiltration, similar to that observed in mice treated with a topical corticosteroid. These data demonstrate the utility of liposome-encapsulated intercellular adhesion molecule-1 antisense oligonucleotide as a novel anti-inflammatory therapeutic.
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Affiliation(s)
- S K Klimuk
- Department of Biochemistry, The University of British Columbia, Vancouver, British Columbia, Canada.
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18
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Scherrer P, Bidaux JE, Kim A, Månson JA, Gotthardt R. Passive vibration damping in an alpine ski by integration of shape memory alloys. ACTA ACUST UNITED AC 1999. [DOI: 10.1051/jp4:1999940] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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19
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Zhang YP, Sekirov L, Saravolac EG, Wheeler JJ, Tardi P, Clow K, Leng E, Sun R, Cullis PR, Scherrer P. Stabilized plasmid-lipid particles for regional gene therapy: formulation and transfection properties. Gene Ther 1999; 6:1438-47. [PMID: 10467368 DOI: 10.1038/sj.gt.3300965] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Previous work (Wheeler et al, Gene Therapy 1999; 6: 271-281) has shown that plasmid DNA can be entrapped in 'stabilized plasmid-lipid particles' (SPLP) containing the fusogenic lipid dioleoylphosphatidylethanolamine (DOPE), low levels (5-10 mol%) of cationic lipid, and stabilized by a polyethyleneglycol (PEG) coating. The PEG moieties are attached to a ceramide anchor containing an arachidoyl acyl group (PEG-CerC20). These SPLP exhibit low transfection potencies in vitro, due in part to the long residence time of the PEG-CerC20 on the SPLP surface. In this work we employed SPLP stabilized by PEG attached to ceramide containing an octanoyl acyl group (PEG-CerC8), which is able to quickly exchange out of the SPLP, to develop systems that give rise to optimized in vitro and in vivo (regional) transfection. A particular objective was to achieve cationic lipid contents that give rise to maximum transfection levels. It is shown that by performing the dialysis procedure in the presence of increasing concentrations of citrate, SPLP containing up to 30 mol% of the cationic lipid dioleoydimethylammonium chloride (DODAC) could be generated. The SPLP produced could be isolated from empty vesicles by sucrose density gradient centrifugation, and exhibited a narrow size distribution (62 +/- 8 nm, as determined by freeze-fracture electron microscopy) and a high plasmid-to-lipid ratio of 65 microg/micromol (corresponding to one plasmid per particle) regardless of the DODAC content. It was found that isolated SPLP containing 20-24 mol% DODAC resulted in optimum transfection of COS-7 and HepG2 cells in vitro, with luciferase expression levels comparable to those achieved for plasmid DNA-cationic lipid complexes. In vivo studies employing an intraperitoneal B16 tumor model and intraperitoneal administration of SPLP also demonstrated maximum luciferase expression for DODAC contents of 20-24 mol% and significantly improved gene expression in tumor tissue as compared with complexes. We conclude that SPLP stabilized by PEG-CerC8 and containing 20-24 mol% cationic lipid are attractive alternatives to plasmid DNA-cationic lipid complexes for regional gene therapy applications.
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Affiliation(s)
- Y P Zhang
- INEX Pharmaceuticals Corporation, Burnaby, BC, Canada
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20
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Schoen P, Chonn A, Cullis PR, Wilschut J, Scherrer P. Gene transfer mediated by fusion protein hemagglutinin reconstituted in cationic lipid vesicles. Gene Ther 1999; 6:823-32. [PMID: 10505107 DOI: 10.1038/sj.gt.3300919] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Hemagglutinin, the membrane fusion protein of influenza virus, is known to mediate a low-pH-dependent fusion reaction between the viral envelope and the limiting membrane of the endosomal cell compartment following cellular uptake of the virus particles by receptor-mediated endocytosis. Here we exploited this activity of hemagglutinin to achieve efficient gene delivery to cultured cells. Hemagglutinin was reconstituted in the presence of the monocationic lipid dioleoyldimethylammonium chloride (DODAC) to permit plasmid binding to the virosome surface. Virosomes with 30 mol% DODAC exhibited a distinct binding capacity for plasmid without causing aggregation. The virosome fusion activity was not affected by the cationic lipid DODAC as demonstrated by low-pH-dependent lipid mixing with erythrocyte ghosts. Efficient cell transfection of BHK-21 cells was observed with virosomes containing 30 mol% DODAC and plasmid encoding for beta-galactosidase (pCMV beta-gal) associated to their surface. The transfection activity observed was dependent on the functional activity of hemagglutinin. Contrary to DNA/cationic lipid complexes the transfection was not dependent on the cationic lipid to DNA charge ratio. Importantly, transfection of BHK-21 cells with pCMV beta-gal by DODAC-containing virosomes did not show any significant signs of cytotoxicity that is commonly observed with DNA/cationic lipid complexes. Together with the high levels of expression of the transgene this highlights the potential of DODAC-containing virosomes as a novel approach in nonviral gene transfer.
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Affiliation(s)
- P Schoen
- Groningen Utrecht Institute for Drug Exploration (GUIDE), Department of Physiological Chemistry, University of Groningen, The Netherlands
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21
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Klimuk SK, Semple SC, Scherrer P, Hope MJ. Contact hypersensitivity: a simple model for the characterization of disease-site targeting by liposomes. Biochim Biophys Acta 1999; 1417:191-201. [PMID: 10082795 DOI: 10.1016/s0005-2736(98)00261-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A murine model of delayed-type hypersensitivity (DTH) is characterized with respect to liposome accumulation at a site of inflammation. Mice were sensitized by painting the abdominal region with a solution of 2,4-dinitrofluorobenzene (DNFB) and inflammation was induced 5 days later by challenging the ear with a dilute solution of DNFB. The inflammatory response was readily monitored by measuring ear thickness (edema) and radiolabeled leukocyte infiltration. Maximum ear swelling and cellular infiltration occurred 24 h after the epicutaneous challenge with the ear returning to normal size after approximately 72 h. We demonstrate that large unilamellar vesicles (LUV) accumulate at the site of inflammation to a level more than 20-fold higher than that measured in the untreated ear. Vesicle delivery to the ear correlated with increased vascular leakage resulting from endothelium remodeling in response to DNFB challenge, and was not a consequence of increased local tissue blood volume. Extravasation occurred only during the first 24 h after ear challenge; after this time the permeability of the endothelium to vesicles returned to normal. We further showed that LUV with a diameter of 120 nm exhibit maximum levels of accumulation, that a polyethylene glycol surface coating does not increase delivery, and that the process can be inhibited by the application of topical corticosteroids at the time of induction. These data and the inflammation model are discussed with respect to developing lipid-based drug delivery vehicles designed to accumulate at inflammatory disease sites.
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Affiliation(s)
- S K Klimuk
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, B.C., Canada.
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Wheeler JJ, Palmer L, Ossanlou M, MacLachlan I, Graham RW, Zhang YP, Hope MJ, Scherrer P, Cullis PR. Stabilized plasmid-lipid particles: construction and characterization. Gene Ther 1999; 6:271-81. [PMID: 10435112 DOI: 10.1038/sj.gt.3300821] [Citation(s) in RCA: 239] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A detergent dialysis procedure is described which allows encapsulation of plasmid DNA within a lipid envelope, where the resulting particle is stabilized in aqueous media by the presence of a poly(ethyleneglycol) (PEG) coating. These 'stabilized plasmid-lipid particles' (SPLP) exhibit an average size of 70 nm in diameter, contain one plasmid per particle and fully protect the encapsulated plasmid from digestion by serum nucleases and E. coli DNase I. Encapsulation is a sensitive function of cationic lipid content, with maximum entrapment observed at dioleoyldimethylammonium chloride (DODAC) contents of 5 to 10 mol%. The formulation process results in plasmid-trapping efficiencies of up to 70% and permits inclusion of 'fusigenic' lipids such as dioleoylphosphatidylethanolamine (DOPE). The in vitro transfection capabilities of SPLP are demonstrated to be strongly dependent on the length of the acyl chain contained in the ceramide group used to anchor the PEG polymer to the surface of the SPLP. Shorter acyl chain lengths result in a PEG coating which can dissociate from the SPLP surface, transforming the SPLP from a stable particle to a transfection-competent entity. It is suggested that SPLP may have utility as systemic gene delivery systems for gene therapy protocols.
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Affiliation(s)
- J J Wheeler
- Inex Pharmaceuticals Corporation, Burnaby, BC, Canada
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23
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Munoz D, Doumenq P, Elhy MC, Guiliano M, Jacquot F, Scherrer P, Mille G. In SituEvolution over an 8 Years' Period of Polycyclic Aromatic Hydrocarbons in Mangrove Soil. Qualitative and Quantitative Analysis by High Resolution GC/MS. Polycycl Aromat Compd 1996. [DOI: 10.1080/10406639608031210] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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24
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Abstract
The pH-sensitive dye 5-iodoacetamidofluorescein was covalently bound to a single cysteine residue introduced by site-directed mutagenesis in position 101 on the cytoplasmic surface or in position 130 on the extracellular surface of the proton pump bacteriorhodopsin. Using time-resolved absorption spectroscopy at 495 nm a transient increase was observed in the apparent pK of the dye attached at residue 101. At pH 7.3 the rise and decay times of this pK-change (approximately 2 ms and approximately 60 ms) correlate well with decay times observed for the M and O intermediates and with the proton uptake time. Interpreting the pK-increase of +0.18 pH-unit in terms of a transiently more negative surface charge density, we calculate a change of -0.80 elementary charge per bacteriorhodopsin at the cytoplasmic surface. It is likely that this charge change is due to the transient deprotonation of aspartate-96. With the label in position 130 on the extracellular surface no transient pK-shift was detected.
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Affiliation(s)
- U Alexiev
- Biophysics Group, Freie Universität Berlin, Germany
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25
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Alexiev U, Mollaaghababa R, Scherrer P, Khorana HG, Heyn MP. Rapid long-range proton diffusion along the surface of the purple membrane and delayed proton transfer into the bulk. Proc Natl Acad Sci U S A 1995; 92:372-6. [PMID: 7831293 PMCID: PMC42742 DOI: 10.1073/pnas.92.2.372] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The pH-indicator dye fluorescein was covalently bound to the surface of the purple membrane at position 72 on the extracellular side of bacteriorhopsin and at positions 101, 105, 160, or 231 on the cytoplasmic side by reacting bromomethylfluorescein with the sulfhydryl groups of cysteines introduced by site-directed mutagenesis. At position 72, on the extracellular surface, the light-induced proton release was detected 71 +/- 4 microseconds after the flash (conditions: pH 7.3, 22 degrees C, and 150 mM KCl). On the cytoplasmic side with the dye at positions 101, 105, and 160, the corresponding values were 77, 76, and 74 +/- 5 microseconds, respectively. Under the same conditions, the proton release time in the bulk medium as detected by pyranine was around 880 microseconds--i.e., slower by a factor of more than 10. The fact that the proton that is released on the extracellular side is detected much faster on the cytoplasmic surface than in the aqueous bulk phase demonstrates that it is retained on the surface and migrates along the purple membrane to the other side. These findings have interesting implications for bioenergetics and support models of local proton coupling. From the small difference between the proton detection times by labels on opposite sides of the membrane, we estimate that at 22 degrees C the proton surface diffusion constant is greater than 3 x 10(-5) cm2/s. At 5 degrees C, the proton release detection time at position 72 equals the faster of the two main rise times of the M intermediate (deprotonation of the Schiff base). At higher temperatures this correlation is gradually lost, but the curved Arrhenius plot for the proton release time is tangential to the linear Arrhenius plot for the rise of M at low temperatures. These observations are compatible with kinetic coupling between Schiff base deprotonation and proton release.
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Affiliation(s)
- U Alexiev
- Department of Physics, Freie Universität, Berlin, Germany
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27
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Scherrer P, Alexiev U, Marti T, Khorana HG, Heyn MP. Covalently bound pH-indicator dyes at selected extracellular or cytoplasmic sites in bacteriorhodopsin. 1. Proton migration along the surface of bacteriorhodopsin micelles and its delayed transfer from surface to bulk. Biochemistry 1994; 33:13684-92. [PMID: 7947777 DOI: 10.1021/bi00250a019] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The kinetics of the light-induced release and uptake of protons was monitored with the optical pH-indicator fluorescein covalently bound to various sites on the extracellular and cytoplasmic surfaces of bacteriorhodopsin. Selective labeling was achieved by reacting (iodoacetamido)fluorescein with the single cysteine residues in bacteriorhodopsin introduced at the desired positions by site-directed mutagenesis. All measurements were performed with bacteriorhodopsin micelles in phospholipid/detergent mixtures in 150 mM KCl at 22 degrees C, pH 7.3. Neither the replacements by cysteine nor the subsequent labeling affected the absorption spectrum of bacteriorhodopsin and the rise times of the M intermediate. Only the decay of M was altered for some bacteriorhodopsin mutants with cysteine residues on the cytoplasmic side. The proton release time detected with fluorescein attached to the extracellular surface (the proton release side) at position 72 (in the loop connecting helices B and C) or 130 (DE loop) was 22 +/- 4 microseconds, clearly faster than that measured with pyranine in the aqueous bulk phase (125 +/- 10 microseconds for wild-type and all mutants studied). For bacteriorhodopsin mutants labeled at positions 35, 101, 160, 229, and 231 in the cytoplasmic loop region (the proton uptake side), the released proton was observed with a time of 61 +/- 4 microseconds. This was about 3-fold slower than the release time on the extracellular side, but still significantly faster than that measured with pyranine in the bulk phase. These results suggest that the released protons are retained on the micellar surface and move more rapidly along this surface to the cytoplasmic side than from the surface to the bulk medium.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P Scherrer
- Department of Physics, Freie Universität Berlin, Germany
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28
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Alexiev U, Marti T, Heyn MP, Khorana HG, Scherrer P. Covalently bound pH-indicator dyes at selected extracellular or cytoplasmic sites in bacteriorhodopsin. 2. Rotational orientation of helices D and E and kinetic correlation between M formation and proton release in bacteriorhodopsin micelles. Biochemistry 1994; 33:13693-9. [PMID: 7947778 DOI: 10.1021/bi00250a020] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The kinetics of the light-induced proton release in bacteriorhodopsin/lipid/detergent micelles was monitored with the optical pH-indicator fluorescein bound covalently to positions 127-134 (helices D and E and the DE loop) on the extracellular side of the protein (the proton release side). Single cysteine residues were introduced in these positions by site-directed mutagenesis, and fluorescein was attached to the sulfhydryl group by reaction with (iodoacetamido)fluorescein. Two characteristic proton release times (approximately 20 and 70 microseconds) were observed. The faster time constant was recorded when fluorescein was attached to positions 127, 130, 131, 132, and 134, while the slower time was observed with the indicator bound to positions 128, 129, and 133. The results are rationalized by assuming specific helical wheel orientations for helics D and E and by making a choice for the residues in the DE loop: (i) The fast time constants occur with fluorescein either attached to residues 130, 131, and 132 that form the DE loop or when pointing toward the interior of the protein with its aqueous proton channel [residues 127 (helix D) and 134 (helix E)]. (ii) The slower time constants are detected with fluorescein exposed to the exterior lipid/detergent phase when bound to residues 128, 129 (both helix D), and 133 (helix E). This interpretation is supported by measurements of the polarity of the label environment which indicate for fluorescein in group i a more hydrophilic environment and for group ii a more hydrophobic environment. The fastest proton release time (10 microseconds) was observed with fluorescein bound to position 127.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- U Alexiev
- Department of Physics, Freie Universität Berlin, Germany
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29
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Alexiev U, Marti T, Heyn MP, Khorana HG, Scherrer P. Surface charge of bacteriorhodopsin detected with covalently bound pH indicators at selected extracellular and cytoplasmic sites. Biochemistry 1994; 33:298-306. [PMID: 8286351 DOI: 10.1021/bi00167a039] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We present a method that allows the detection of the surface charge density of bacteriorhodopsin (bR) at any selected protein surface site. The optical pH indicator fluorescein was covalently bound to the sulfhydryl groups of single cysteine residues, which were introduced at selected positions in bR by site-directed mutagenesis. On the extracellular side, the positions were in the BC loop (72) and in the DE loop (129-134). On the cytoplasmic side, one position in each loop was labeled: 35 (AB), 101 (CD), 160 (EF), and 231 (carboxy tail). The apparent pKs of fluorescein in these positions were determined for various salt concentrations. The local surface charge density was calculated from the dependence of the apparent pK of the dye on the ionic strength using the Gouy-Chapman equation. The surface charge density at pH 6.6 is more negative on the cytoplasmic side (averaged over all positions, -2.5 +/- 0.2 elementary charges per bR) than on the extracellular side (average, -1.8 +/- 0.2 elementary charges per bR) with little variation along the surface. Since the experiments were performed with electrically neutral CHAPS/DMPC micelles, these values represent the charge present on bR itself.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- U Alexiev
- Department of Physics, Freie Universität Berlin, Germany
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30
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Scherrer P, Quiniou E. [Melancholia and electroshock. A case of beneficial therapeutic eagerness]. Ann Med Psychol (Paris) 1991; 149:345-7. [PMID: 1958038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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31
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Scherrer P. [Responsibility and responsibilization of patients with mental disorders]. Ann Med Psychol (Paris) 1990; 148:635-6; discussion 636-8. [PMID: 2091520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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33
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Abstract
On the basis of data obtained by spectroscopic analysis and chromatography of retinal extracts, a consensus has been adopted that dark-adapted purple membrane (pm) contains 13-cis- and all-trans-retinal in equal amounts, whereas the light-adapted membrane contains all-trans-retinal only. We have developed an improved extraction technique which extracts up to 70% of the retinal in pm within 4 min. In the extracts from dark-adapted pm at room temperature, we consistently find 66-67% 13-cis-retinal and 33-34% all-trans-retinal, and more than 98.5% all-trans isomer in light-adapted samples. The spectrum obtained by reconstitution of bacterioopsin with 13-cis-retinal at 2 degrees C (to minimize isomerization) shows an absorbance maximum at 554 nm and agrees well with the spectrum for the 13-cis component calculated from the dark-adapted and light-adapted bR spectra with our extraction data. The ratio of 13-cis:all-trans isomer in dark-adapted pm is 2:1 and nearly constant between 0 and 38 degrees C but begins to decrease distinctly above 40 degrees C, and more rapidly near 70 degrees C, reaching 0.75 at 90 degrees C. The van't Hoff plot of the isomer ratio shows a nonlinear temperature dependence above 40 degrees C, indicating a more complex system than a simple thermal 13-cis/all-trans isomer equilibrium. We attribute the broadening, absorbance decrease, and blut shift of the visible absorption band with increasing temperature to the appearance of at least one and possibly two or three new chromophores which contain, mainly or exclusively, the all-trans isomer.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- P Scherrer
- Cardiovascular Research Institute, University of California, San Francisco 94143
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34
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Roepe P, Scherrer P, Ahl PL, Das Gupta SK, Bogomolni RA, Herzfeld J, Rothschild KJ. Tyrosine and carboxyl protonation changes in the bacteriorhodopsin photocycle. 2. Tyrosines-26 and -64. Biochemistry 1987; 26:6708-17. [PMID: 3427039 DOI: 10.1021/bi00395a021] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Low-temperature Fourier transform infrared (FTIR) and UV difference spectroscopies combined with selective tyrosine nitration and tyrosine isotopic labeling have been used to investigate the participation of tyrosines-26 and -64 in the bacteriorhodopsin (bR) photocycle. Nitration of Tyr-26 has no detectable effect on the FTIR or UV difference spectra of the BR570----K630 or BR570----M412 transitions. In contrast, nitration of Tyr-64 causes changes in both the FTIR and UV spectra of these transitions. However, this nitration does not alter tyrosine peaks in the FTIR difference spectra which have previously been associated with the protonation of a tyrosinate by K630 and the deprotonation of a tyrosine by M412 [Roepe, P., Ahl, P. L., Das Gupta, S. K., Herzfeld, J., & Rothschild, K. J. (1987) Biochemistry (preceding paper in this issue)]. Instead, Tyr-64 nitration appears to affect other tyrosine peaks. These results and changes in UV difference spectra upon Tyr-64 nitration are consistent with the deprotonation of Tyr-64 by M412 as concluded previously [Scherrer, P., & Stoeckenius, W. (1985) Biochemistry 24, 7733-7740]. Effects on chromophore vibrations caused by Tyr-64 nitration are unaltered upon reducing the nitrotyrosine to aminotyrosine with sodium dithionite. Finally, nitro-Tyr-64 causes a shift in the frequency of a positive peak at 1739 cm-1 in the BR570----M412 FTIR difference spectrum which reflects the protonation of a carboxyl-containing residue [Engelhard, M., Gerwert, K., Hess, B., Kreutz, W., & Siebert, F. (1985) Biochemistry 24, 400-407; Roepe, P., Ahl, P. L., Das Gupta, S. K., Herzfeld, J., & Rothschild, K. J. (1987) Biochemistry (preceding paper in this issue)]. The shift does not occur for samples containing amino-Tyr-64. These data suggest that Tyr-64 may interact with this carboxyl group.
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Affiliation(s)
- P Roepe
- Department of Physics, Boston University, Massachusetts 02215
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35
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Scherrer P, Quiniou E. [Severe mental disorders and the problem of hospitalization]. Ann Med Psychol (Paris) 1987; 145:469-82. [PMID: 3688702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The problem of the hospitalization of patients with severe mental disorders. In relating three clinical cases, the author's purpose is to show that sometimes an hospitalization of long duration is necessary and that the psychiatrist has to be able to assume that decision for the patient's sake. In the first two cases, suicide was the issue, each time after a too-short period of hospitalization, given the antecedents in the first case, and in the second, not allowing that an efficient treatment be set up and accepted. The third case shows how a sufficiently long hospitalization (about 2 months) could enable the setting of a long-duration treatment which led to a sensible improvement of the patient's state.
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36
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Scherrer P, McGinnis K, Bogomolni RA. Biochemical and spectroscopic characterization of the blue-green photoreceptor in Halobacterium halobium. Proc Natl Acad Sci U S A 1987; 84:402-6. [PMID: 3467364 PMCID: PMC304215 DOI: 10.1073/pnas.84.2.402] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Spectroscopic evidence indicates the presence of a second sensory receptor sR-II in Halobacterium halobium, which causes a repellent response to blue-green light. Reactions with hydroxylamine and NaCNBH3 and reconstitution of the bleached pigment with retinal show that it is very similar to the other retinylidene pigments bacteriorhodopsin, halorhodopsin, and especially the earlier-discovered phototaxis receptor, sensory rhodopsin, renamed sR-I587. The second sensory receptor, sR-II480, has an absorbance maximum at 480 nm and undergoes a cyclic photoreaction with a half-time of approximately 200 msec. Its predominant photocycle intermediate absorbs maximally near 360 nm. The receptor can be detected spectroscopically in the presence of sR-I587 and quantitated through its transient response to 450-nm excitation. It is selectively bleached by low hydroxylamine concentrations that are insufficient to bleach sR-I587 significantly. Its photochemical and phototactic activities can be restored by addition of retinal. The mobility of the receptor, on NaDodSO4/polyacrylamide gels, was similar or identical to that of sR-I587 and slightly faster than bacteriorhodopsin, yielding an apparent molecular mass of 23-24 kDa.
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37
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Scherrer P, Schelling JL. [Drug therapy of chronic pain in cancer patients. Survey among hospitalized patients]. Rev Med Suisse Romande 1987; 107:69-76. [PMID: 3563225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Wolff EK, Bogomolni RA, Scherrer P, Hess B, Stoeckenius W. Color discrimination in halobacteria: spectroscopic characterization of a second sensory receptor covering the blue-green region of the spectrum. Proc Natl Acad Sci U S A 1986; 83:7272-6. [PMID: 3463965 PMCID: PMC386698 DOI: 10.1073/pnas.83.19.7272] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Halobacterium halobium is attracted by green and red light and repelled by blue-green and shorter wavelength light. a photochromic, rhodopsin-like protein in the cell membrane, sensory rhodopsin sR587, has been identified as the receptor for the long-wavelength and near-UV stimuli. Discrepancies between the action spectrum for the repellent effect of blue light and the absorption spectrum of sR587 and its photocycle intermediate S373 strongly suggest the existence of an additional photoreceptor for the blue region of the spectrum. Transient light-induced absorbance changes in intact cells and cell membranes show, in addition to sR587, the presence of a second photoactive pigment with maximal absorption near 480 nm. It undergoes a cyclic photoreaction with a half-time of 150 msec. One intermediate state with maximal absorption near 360 nm has been resolved. The spectral properties of the new pigment are consistent with a function as the postulated photoreceptor for the repellent effect of blue light. The phototactic reactions and both pigments are absent when retinal synthesis is blocked; both can be restored by the addition of retinal. These results confirm and extend similar observations by Takahashi et al. [Takahashi, T., Tomioka, H., Kamo, N. & Kobatake, Y. (1985) FEMS Microbiol. Lett. 28, 161-164]. The archaeobacterium H. halobium thus uses two different mechanisms for color discrimination; it uses two rhodopsin-like receptors with different spectral sensitivities and also the photochromicity of at least one of these receptors to distinguish between three regions covering the visible and near-UV spectrum.
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Scherrer P, Perret C. [Prevention of acute renal insufficiency due to nontraumatic rhabdomyolysis]. Schweiz Med Wochenschr 1986; 116:572-4. [PMID: 3715436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Nine patients with nontraumatic rhabdomyolysis underwent preventive treatment for acute renal failure (ARF) (vascular filling, furosemide, dopamine, Na bicarbonate, allopurinol). Four patients developed functional azotemia and 4 others ARF with conserved diuresis and normalization of renal function without substitutive treatment. Only one patient remained oligoanuric and needed hemodialysis for 3 weeks. Comparing these 3 groups it appears that the severity of the renal impairment is due on one hand to the extent of the muscular lysis and on the other to early commencement of preventive treatment.
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40
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Abstract
In the dark, all titratable tyrosine residues of bacteriorhodopsin have pK's of greater than 11.0, which may be caused by the hydrophobic environment for buried residues and by high negative charge density for surface residues [Scherrer, P., & Stoeckenius, W. (1984) Biochemistry 23, 6195-6202]. Under illumination, deprotonation of only one tyrosine is observed in the micro- and millisecond time ranges of the photocycle; this is Tyr-64. Nitration of Tyr-64 decreases the chromophore absorbance, shifts the absorption maximum to 535 nm, and affects photocycle kinetics. However, restoring its native pK by reduction after nitration has no effect on the changes in photocycle kinetics or absorbance of the chromophore. Nitration of Tyr-64 apparently causes a conformational change in bR, which is independent of the pK of its phenolic group. These observations contradict earlier conclusions that in the photocycle a tyrosine residue directly interacts with the Schiff base during its deprotonation or reprotonation. The protonation state of Tyr-26 and the alkaline chromophore transition are correlated, as shown earlier (Scherrer & Stoeckenius, 1984). Lowering the pK of Tyr-26 by nitration decreases the M-decay rate, and this effect is partially reversed by reduction of the nitro group. We conclude that Tyr-26 may be located close to the chromophore and interact with it; but its protonation state does not change at physiological pH and in the microsecond time range of the photocycle. Tyr-64 is apparently located at or close to the external surface; its modification strongly affects the chromophore but apparently indirectly and not through its protonation changes.(ABSTRACT TRUNCATED AT 250 WORDS)
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41
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Scherrer P, Delaloye-Bischof A, Turini G, Perret C. [Myocardial involvement in nontraumatic rhabdomyolysis following an opiate overdose]. Schweiz Med Wochenschr 1985; 115:1166-70. [PMID: 4048911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Eight young addicts developed rhabdomyolysis as a complication of heroin overdose. ECG, plasma enzyme time activity curves and thallium myocardial scintigraphy were highly suggestive of a myocardial lesion associated with rhabdomyolysis. Such changes were particularly striking in 3 patients with acute left ventricular failure, as shown by a hemodynamic investigation (3 patients) and by echocardiography (1 patient). All patients recovered but myocardial scintigraphy and ECG remained abnormal for a period ranging from 8 months to 3 years following the acute episode. Although associated metabolic changes may play a role in myocardial dysfunction, the most likely mechanism appears to be a direct toxic effect of heroin on cardiac muscle.
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42
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Scherrer P. [Transsexuals or pseudotranssexuals?]. Ann Med Psychol (Paris) 1985; 143:549-60. [PMID: 4083651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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43
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Scherrer P, Gonvers JJ, Ruzicka J, Schnyder P, Godat A. [A case of Whipple disease with a pseudotumorous presentation: differential diagnosis with mesenteric panniculitis]. Schweiz Med Wochenschr 1984; 114:272-276. [PMID: 6200927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
A case of Whipple's disease initially presenting as an inflammatory, granulomatous and pseudotumorous infiltration of the mesenterium is discussed. The initial diagnosis of mesenteric panniculitis was invalidated by the typical histological findings of Whipple's disease in a duodenal biopsy performed 18 months later for malabsorption syndrome. This case illustrates the difficulties besetting differential diagnosis of inflammatory and granulomatous lesions of the mesenterium.
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44
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Scherrer P, Wauters JP, Polikar R, Campiche M. [The place of kidney biopsies in the diagnosis of isolated hematuria]. Schweiz Med Wochenschr 1984; 114:232-6. [PMID: 6701504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Twenty-six patients with idiopathic hematuria, i.e. with normal intravenous pyelography, without arterial hypertension, renal failure or significant proteinuria, underwent renal biopsy in our institution between 1973 and 1981. Segmental proliferative endocapillary glomerulonephritis was diagnosed in 13 cases; in the other 13 patients the renal tissue was either normal (6) or presented only minor lesions of the mesangium (5) or interstitial tissue (2). Twenty-two patients underwent a follow-up examination after a mean of 51 months (range 12-120). The hematuria had disappeared in half of them and no patients had developed hypertension or renal failure. These results suggest that in cases of idiopathic hematuria renal biopsy is not indicated for prognostic or therapeutic reasons, though in some cases it may avoid repeated and potentially dangerous investigations.
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45
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Scherrer P. [The 1940 debacle: gathering the mental patients at the Psychiatric Hospital of Auxerre]. Ann Med Psychol (Paris) 1984; 142:266-70. [PMID: 6465733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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46
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Scherrer P, Potez H, Nedelec JL. [A severe case of obsessional psychoneurosis treated with behavior therapy, then narcoanalysis]. Ann Med Psychol (Paris) 1983; 141:987-97. [PMID: 6666922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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47
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Scherrer P. [A case of very unusual erotomania or "erotomaniac relation"]. Ann Med Psychol (Paris) 1982; 140:923-30. [PMID: 7183228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Scherrer P. [The case of Marie-Louise N...A manic-depressive patient confined to a general hospital after a stroke followed by aphasia]. Ann Med Psychol (Paris) 1982; 140:530-9. [PMID: 7181250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Scherrer P, Rousselot Y. [Case report of Huntington chorea with delusional manifestations]. Ann Med Psychol (Paris) 1982; 140:353-6. [PMID: 6215874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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