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Samuel I, Ben-Haroush Schyr R, Arad Y, Attali T, Azulai S, Bergel M, Halfon A, Hefetz L, Hirsch T, Israeli H, Lax N, Nitzan K, Sender D, Sweetat S, Okun E, Rosenmann H, Ben-Zvi D. Sleeve Gastrectomy Reduces Glycemia but Does Not Affect Cognitive Impairment in Lean 5xFAD Mice. Front Neurosci 2022; 16:937663. [PMID: 36033613 PMCID: PMC9403181 DOI: 10.3389/fnins.2022.937663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 06/23/2022] [Indexed: 11/13/2022] Open
Abstract
Obesity and hyperglycemia are risk factors for cognitive decline and for the development of Alzheimer’s Disease (AD). Bariatric surgery is an effective treatment for obesity that was shown to improve cognitive decline in obese patients. Bariatric surgery was shown to exert weight loss independent effects on metabolic diseases such as type 2 diabetes. We tested whether sleeve gastrectomy (SG), a common bariatric surgery, can affect the cognitive impairment in lean, normoglycemic female 5xFAD mice, a genetic model for AD. 5xFAD mice and wild-type (WT) littermates underwent SG or sham surgery at the age of 5 months and were tested for metabolic, behavioral, and molecular phenotypes 90 days later. SG led to a reduction in blood glucose levels and total plasma cholesterol levels in 5xFAD mice without inducing weight loss. However, the surgery did not affect the outcomes of long-term spatial memory tests in these mice. Analysis of β-Amyloid plaques corroborated the behavioral studies in showing no effect of surgery on the molecular phenotype of 5xFAD mice. In conclusion, SG leads to an improved metabolic profile in lean female 5xFAD mice without inducing weight loss but does not affect the brain pathology or behavioral phenotype. Our results suggest that the positive effects of bariatric surgery on cognitive decline in obese patients are likely attributed to weight loss and improvement in obesity sequelae, and not to weight loss independent effects of surgery.
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Affiliation(s)
- Itia Samuel
- Department of Developmental Biology and Cancer Research, The Institute of Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Rachel Ben-Haroush Schyr
- Department of Developmental Biology and Cancer Research, The Institute of Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Yhara Arad
- Department of Developmental Biology and Cancer Research, The Institute of Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
- Department of Military Medicine and Tzameret, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Tamar Attali
- Department of Developmental Biology and Cancer Research, The Institute of Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Shira Azulai
- Department of Developmental Biology and Cancer Research, The Institute of Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Michael Bergel
- Department of Developmental Biology and Cancer Research, The Institute of Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Aviv Halfon
- Department of Developmental Biology and Cancer Research, The Institute of Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
- Department of Military Medicine and Tzameret, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Liron Hefetz
- Department of Developmental Biology and Cancer Research, The Institute of Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
- Department of Military Medicine and Tzameret, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Tamir Hirsch
- The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
- The Paul Feder Laboratory on Alzheimer’s Disease Research, Bar-Ilan University, Ramat Gan, Israel
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Hadar Israeli
- Department of Developmental Biology and Cancer Research, The Institute of Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Neta Lax
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Keren Nitzan
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Dana Sender
- Department of Developmental Biology and Cancer Research, The Institute of Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Sahar Sweetat
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Eitan Okun
- The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
- The Paul Feder Laboratory on Alzheimer’s Disease Research, Bar-Ilan University, Ramat Gan, Israel
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Hanna Rosenmann
- Department of Neurology, The Agnes Ginges Center for Human Neurogenetics, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
- *Correspondence: Hanna Rosenmann,
| | - Danny Ben-Zvi
- Department of Developmental Biology and Cancer Research, The Institute of Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
- Danny Ben-Zvi,
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Abu-Gazala S, Bergel M, Arad Y, Hefetz L, Azulai S, Baker A, Haran A, Israeli H, Kleiman D, Samuel I, Tsubary U, Permyakova A, Tam J, Ben-Haroush Schyr R, Ben-Zvi D. Generation and characterization of a mouse model for one anastomosis gastric bypass surgery. Am J Physiol Endocrinol Metab 2022; 322:E414-E424. [PMID: 35285295 DOI: 10.1152/ajpendo.00416.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
One anastomosis gastric bypass (OAGB) surgery became a common bariatric procedure in recent years. In this surgery, the distal stomach, duodenum, and proximal jejunum are bypassed, leading to weight loss, improvement in metabolic parameters, and a change in hormonal secretion. We sought to generate and characterize a mouse model for OAGB. Mice fed for 26 wk on a high-fat diet were assigned to OAGB, sham surgery, or caloric restriction and were followed for 50 more days on a high-fat diet. Physiological and histological parameters of the mice were compared during and at the end of the experiment. OAGB-operated mice lost weight and displayed low levels of plasma lipids, high insulin sensitivity, and rapid glucose metabolism compared with sham-operated mice. OAGB-operated mice had higher energy expenditure, higher levels of glucagon-like peptide (GLP-1), and lower albumin than weight-matched calorie-restricted mice. There was no difference in the histology of the endocrine pancreas. The livers of OAGB mice had little hepatic steatosis yet presented with a large number of phagocytic cells. The OAGB mouse model recapitulates many of the phenotypes described in patients that underwent OAGB and enables molecular and physiological studies on the outcome of this surgery.NEW & NOTEWORTHY A mouse model for one anastomosis gastric bypass (OAGB) surgery displays similar outcomes to clinical reports and enables to study the weight loss-dependent and -independent effects of this bariatric surgery.
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Affiliation(s)
- Samir Abu-Gazala
- Department of Surgery, Hadassah Medical Center-Ein Kerem, Jerusalem, Israel
- Department of Surgery, Penn Transplant Institute, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Michael Bergel
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Yhara Arad
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
- Department of Military Medicine and Tzameret, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Liron Hefetz
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
- Department of Military Medicine and Tzameret, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Shira Azulai
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Aaron Baker
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Arnon Haran
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Hadar Israeli
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Doron Kleiman
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Itia Samuel
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Uria Tsubary
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
- Department of Military Medicine and Tzameret, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Anna Permyakova
- Obesity and Metabolism Laboratory, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Joseph Tam
- Obesity and Metabolism Laboratory, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Rachel Ben-Haroush Schyr
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Danny Ben-Zvi
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
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Hefetz L, Ben-Haroush Schyr R, Bergel M, Arad Y, Kleiman D, Israeli H, Samuel I, Azulai S, Haran A, Levy Y, Sender D, Rottenstreich A, Ben-Zvi D. Maternal antagonism of Glp1 reverses the adverse outcomes of sleeve gastrectomy on mouse offspring. JCI Insight 2022; 7:156424. [PMID: 35393955 PMCID: PMC9057621 DOI: 10.1172/jci.insight.156424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/25/2022] [Indexed: 12/30/2022] Open
Abstract
Mothers that underwent bariatric surgery are at higher risk for delivering a small-for-gestational age (SGA) infant. This phenomenon is attributed to malabsorption and rapid weight loss following surgery. We compared pregnancy outcomes in lean mice that underwent sham surgery or sleeve gastrectomy (SG). SG led to a reduction in glucose levels and an increase in postprandial levels of glucagon-like peptide 1 (Glp1) without affecting mice weight during pregnancy. Pups of SG-operated mice (SG pups) were born SGA. The placenta and pancreas of the pups were not affected by SG, although a high-fat diet caused hepatic steatosis and glucose intolerance in male SG pups. Treatment with a Glp1 receptor antagonist during pregnancy normalized the birth weight of SG pups and diminished the adverse response to a high-fat diet without affecting glucose levels of pregnant mice. The antagonist did not affect the birth weight of pups of sham-operated mice. Our findings link elevated Glp1 signaling, rather than weight loss, to the increased prevalence of SGA births following bariatric surgery with metabolic consequences for the offspring. The long-term effects of bariatric surgery on the metabolic health of offspring of patients require further investigation.
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Affiliation(s)
- Liron Hefetz
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel.,Department of Military Medicine and Tzameret, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel, and Medical Corps, Israel Defense Forces, Israel
| | - Rachel Ben-Haroush Schyr
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Michael Bergel
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Yhara Arad
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel.,Department of Military Medicine and Tzameret, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel, and Medical Corps, Israel Defense Forces, Israel
| | - Doron Kleiman
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Hadar Israeli
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Itia Samuel
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Shira Azulai
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Arnon Haran
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Yovel Levy
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Dana Sender
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Amihai Rottenstreich
- Department of Obstetrics and Gynecology and.,Faculty of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Danny Ben-Zvi
- Department of Developmental Biology and Cancer Research, Institute of Medical Research Israel-Canada, Hebrew University-Hadassah Medical School, Jerusalem, Israel
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Ben-Haroush Schyr R, Al-Kurd A, Moalem B, Permyakova A, Israeli H, Bardugo A, Arad Y, Hefetz L, Bergel M, Haran A, Azar S, Magenheim I, Tam J, Grinbaum R, Ben-Zvi D. Sleeve Gastrectomy Suppresses Hepatic Glucose Production and Increases Hepatic Insulin Clearance Independent of Weight Loss. Diabetes 2021; 70:2289-2298. [PMID: 34341005 PMCID: PMC8576500 DOI: 10.2337/db21-0251] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 07/28/2021] [Indexed: 11/13/2022]
Abstract
Bariatric operations induce weight loss, which is associated with an improvement in hepatic steatosis and a reduction in hepatic glucose production. It is not clear whether these outcomes are entirely due to weight loss, or whether the new anatomy imposed by the surgery contributes to the improvement in the metabolic function of the liver. We performed vertical sleeve gastrectomy (VSG) on obese mice provided with a high-fat high-sucrose diet and compared them to diet and weight-matched sham-operated mice (WMS). At 40 days after surgery, VSG-operated mice displayed less hepatic steatosis compared with WMS. By measuring the fasting glucose and insulin levels in the blood vessels feeding and draining the liver, we showed directly that hepatic glucose production was suppressed after VSG. Insulin levels were elevated in the portal vein, and hepatic insulin clearance was elevated in VSG-operated mice. The hepatic expression of genes associated with insulin clearance was upregulated. We repeated the experiment in lean mice and observed that portal insulin and glucagon are elevated, but only insulin clearance is increased in VSG-operated mice. In conclusion, direct measurement of glucose and insulin in the blood entering and leaving the liver shows that VSG affects glucose and insulin metabolism through mechanisms independent of weight loss and diet.
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Affiliation(s)
- Rachel Ben-Haroush Schyr
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School-The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Abbas Al-Kurd
- Department of Surgery, Hadassah Medical Center-Mt. Scopus, Jerusalem, Israel
| | - Botros Moalem
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School-The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Anna Permyakova
- Obesity and Metabolism Laboratory, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Hadar Israeli
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School-The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Aya Bardugo
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School-The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Yhara Arad
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School-The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Liron Hefetz
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School-The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Michael Bergel
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School-The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Arnon Haran
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School-The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Shahar Azar
- Obesity and Metabolism Laboratory, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Itia Magenheim
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School-The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Joseph Tam
- Obesity and Metabolism Laboratory, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ronit Grinbaum
- Department of Surgery, Hadassah Medical Center-Mt. Scopus, Jerusalem, Israel
| | - Danny Ben-Zvi
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School-The Hebrew University of Jerusalem, Jerusalem, Israel
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Azar S, Udi S, Drori A, Hadar R, Nemirovski A, Vemuri KV, Miller M, Sherill-Rofe D, Arad Y, Gur-Wahnon D, Li X, Makriyannis A, Ben-Zvi D, Tabach Y, Ben-Dov IZ, Tam J. Reversal of diet-induced hepatic steatosis by peripheral CB1 receptor blockade in mice is p53/miRNA-22/SIRT1/PPARα dependent. Mol Metab 2020; 42:101087. [PMID: 32987186 PMCID: PMC7563015 DOI: 10.1016/j.molmet.2020.101087] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 09/03/2020] [Accepted: 09/17/2020] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE The endocannabinoid (eCB) system is increasingly recognized as being crucially important in obesity-related hepatic steatosis. By activating the hepatic cannabinoid-1 receptor (CB1R), eCBs modulate lipogenesis and fatty acid oxidation. However, the underlying molecular mechanisms are largely unknown. METHODS We combined unbiased bioinformatics techniques, mouse genetic manipulations, multiple pharmacological, molecular, and cellular biology approaches, and genomic sequencing to systematically decipher the role of the hepatic CB1R in modulating fat utilization in the liver and explored the downstream molecular mechanisms. RESULTS Using an unbiased normalized phylogenetic profiling analysis, we found that the CB1R evolutionarily coevolves with peroxisome proliferator-activated receptor-alpha (PPARα), a key regulator of hepatic lipid metabolism. In diet-induced obese (DIO) mice, peripheral CB1R blockade (using AM6545) induced the reversal of hepatic steatosis and improved liver injury in WT, but not in PPARα-/- mice. The antisteatotic effect mediated by AM6545 in WT DIO mice was accompanied by increased hepatic expression and activity of PPARα as well as elevated hepatic levels of the PPARα-activating eCB-like molecules oleoylethanolamide and palmitoylethanolamide. Moreover, AM6545 was unable to rescue hepatic steatosis in DIO mice lacking liver sirtuin 1 (SIRT1), an upstream regulator of PPARα. Both of these signaling molecules were modulated by the CB1R as measured in hepatocytes exposed to lipotoxic conditions or treated with CB1R agonists in the absence/presence of AM6545. Furthermore, using microRNA transcriptomic profiling, we found that the CB1R regulated the hepatic expression, acetylation, and transcriptional activity of p53, resulting in the enhanced expression of miR-22, which was found to specifically target SIRT1 and PPARα. CONCLUSIONS We provide strong evidence for a functional role of the p53/miR-22/SIRT1/PPARα signaling pathway in potentially mediating the antisteatotic effect of peripherally restricted CB1R blockade.
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Affiliation(s)
- Shahar Azar
- Obesity and Metabolism Laboratory, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Shiran Udi
- Obesity and Metabolism Laboratory, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Adi Drori
- Obesity and Metabolism Laboratory, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Rivka Hadar
- Obesity and Metabolism Laboratory, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Alina Nemirovski
- Obesity and Metabolism Laboratory, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Kiran V Vemuri
- Center for Drug Discovery, Northeastern University, Boston, MA, USA
| | - Maya Miller
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Dana Sherill-Rofe
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Yhara Arad
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Devorah Gur-Wahnon
- Laboratory of Medical Transcriptomics, Department of Nephrology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Xiaoling Li
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | | | - Danny Ben-Zvi
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Yuval Tabach
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, Hadassah Medical School, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Iddo Z Ben-Dov
- Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
| | - Joseph Tam
- Obesity and Metabolism Laboratory, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel.
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Fisch S, Bachner-Hinenzon N, Ertracht O, Guo L, Arad Y, Ben-Zvi D, Liao R, Schneiderman J. Localized Antileptin Therapy Prevents Aortic Root Dilatation and Preserves Left Ventricular Systolic Function in a Murine Model of Marfan Syndrome. J Am Heart Assoc 2020; 9:e014761. [PMID: 32378446 PMCID: PMC7660857 DOI: 10.1161/jaha.119.014761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Marfan syndrome (MFS) is a genetically transmitted connective tissue disorder characterized by aortic root dilatation, dissection, and rupture. Molecularly, MFS pathological features have been shown to be driven by increased angiotensin II in the aortic wall. Using an angiotensin II-driven aneurysm mouse model, we have recently demonstrated that local inhibition of leptin activity restricts aneurysm formation in the ascending and abdominal aorta. As we observed de novo leptin synthesis in the ascending aortic aneurysm wall of patients with MFS, we hypothesized that local counteracting of leptin activity in MFS may also prevent aortic cardiovascular complications in this context. Methods and Results Fbn1C1039G/+ mice underwent periaortic application of low-dose leptin antagonist at the aortic root. Treatment abolished medial degeneration and prevented increase in aortic root diameter (P<0.001). High levels of leptin, transforming growth factor β1, Phosphorylated Small mothers against decapentaplegic 2, and angiotensin-converting enzyme 1 observed in saline-treated MFS mice were downregulated in leptin antagonist-treated animals (P<0.01, P<0.05, P<0.001, and P<0.001, respectively). Leptin and angiotensin-converting enzyme 1 expression levels in left ventricular cardiomyocytes were also decreased (P<0.001) and coincided with prevention of left ventricular hypertrophy and aortic and mitral valve leaflet thickening (P<0.01 and P<0.05, respectively) and systolic function preservation. Conclusions Local, periaortic application of leptin antagonist prevented aortic root dilatation and left ventricular valve remodeling, preserving left ventricular systolic function in an MFS mouse model. Our results suggest that local inhibition of leptin may constitute a novel, stand-alone approach to prevent MFS aortic root aneurysms and potentially other similar angiotensin II-driven aortic pathological features.
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Affiliation(s)
- Sudeshna Fisch
- Cardiovascular Physiology Core Department of Medicine Brigham and Women's Hospital Harvard Medical School Boston MA
| | | | - Offir Ertracht
- Eliachar Research Laboratory Galilee Medical Center Nahariya Israel
| | | | - Yhara Arad
- Department of Developmental Biology and Cancer Research Institute of Medical Research Israel-Canada Hebrew University of Jerusalem-Hadassah Medical School Jerusalem Israel
| | - Danny Ben-Zvi
- Department of Developmental Biology and Cancer Research Institute of Medical Research Israel-Canada Hebrew University of Jerusalem-Hadassah Medical School Jerusalem Israel
| | - Ronglih Liao
- Cardiovascular Physiology Core Department of Medicine Brigham and Women's Hospital Harvard Medical School Boston MA.,Stanford University School of Medicine Cardiovascular Institute Stanford CA
| | - Jacob Schneiderman
- Department of Vascular Surgery Sheba Medical Center Sackler Faculty of Medicine Tel Aviv University Tel Aviv Israel
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7
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Arad Y, Newstein D, Cadet F, Roth M, Guerci AD. Association of multiple risk factors and insulin resistance with increased prevalence of asymptomatic coronary artery disease by an electron-beam computed tomographic study. Arterioscler Thromb Vasc Biol 2001; 21:2051-8. [PMID: 11742884 DOI: 10.1161/hq1201.100257] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.3] [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: 11/16/2022]
Abstract
The insulin resistance syndrome, consisting of resistance to insulin and several metabolic abnormalities, is associated with an increased risk of symptomatic coronary artery disease. Asymptomatic persons with increased coronary calcification have increased coronary plaque and an increased likelihood of future cardiovascular events. Electron-beam computed tomography-derived coronary artery calcium scores, metabolic and anthropometric parameters, and fasting and stimulated concentrations of glucose and insulin were measured in 1160 asymptomatic men and women. Coronary artery calcium scores were positively correlated with glucose, insulin, and homeostasis model assessment (HOMA) insulin resistance. Calcium scores were positively correlated with intra-abdominal adiposity, age, total cholesterol/high density lipoprotein (HDL) ratio, low density lipoprotein, triglycerides, blood pressure, and HOMA beta cell function and inversely correlated with HDL and peripheral fat. These correlations, except for 2-hour glucose, remained significant for all subjects with fasting serum glucose <126 mg/dL or all subjects with fasting serum glucose 110 mg/dL. In a multivariate analysis, age, sex, family history of premature coronary artery disease, intra-abdominal adiposity, low density lipoprotein, and smoking independently predicted calcium scores. Blood pressure, HDL, triglycerides, glucose, insulin, and HOMA insulin resistance or beta cell function were not independently correlated with coronary artery calcium scores. Asymptomatic individuals with insulin resistance have elevated coronary calcium scores. The association between insulin resistance and coronary calcification persists with impaired glucose tolerance and normal fasting serum glucose. Central/visceral adiposity may be a determinant of insulin resistance and atherosclerosis even in asymptomatic nondiabetic persons.
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Affiliation(s)
- Y Arad
- Department of Preventive Cardiology, St. Francis Hospital, Roslyn, New York 11576, USA.
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8
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Affiliation(s)
- J J Popma
- Department of Medicine, Cardiovascular Division, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115, USA.
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Arad Y, Newstein D, Roth M, Guerci AD. Rationale and design of the St. Francis Heart Study: a randomized clinical trial of atorvastatin plus antioxidants in asymptomatic persons with elevated coronary calcification. Control Clin Trials 2001; 22:553-72. [PMID: 11578788 DOI: 10.1016/s0197-2456(01)00146-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Early detection of asymptomatic subjects who are at risk for future cardiovascular events may allow for earlier medical treatment in order to prevent disease progression and future events. Electron-beam computed tomography accurately identifies people with increased coronary calcification, which is correlated with increased coronary plaque mass, increased likelihood of obstructive coronary disease, and increased likelihood of future cardiovascular events. The St. Francis Heart Study is a single-center combination study of men and women 50-70 years old that includes a natural history study of the relation between calcium scores and cardiovascular events (n = 5582), the association of calcium scores with traditional and nontraditional coronary disease risk factors (n = 1160), and a randomized clinical trial designed to assess the benefit of combination treatment with atorvastatin, vitamin C, and vitamin E, as compared to placebos, in subjects with elevated age- and gender-adjusted coronary calcification (n = 1007). Mean follow-up duration will be 4 years. The study is proceeding on schedule with anticipated completion by August 2002. It should provide important information regarding the benefits of treating asymptomatic men and women who have elevated coronary artery calcium, using cholesterol reduction and antioxidant therapy. The article describes the design of the St. Francis Heart Study.
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Affiliation(s)
- Y Arad
- Department of Preventive Cardiology, St. Francis Hospital, Roslyn, NY 11576, USA.
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Abstract
Deficiencies in traditional cardiovascular risk-factor assessment in asymptomatic individuals have led to the use of electron beam computed tomography (CT) scanning as a screening test for coronary artery disease. This novel approach is based on a secure pathologic foundation: the risk of coronary disease events is proportional to the severity and extent of underlying coronary atherosclerosis, and in middle-aged and elderly adults, calcified plaque is closely related to total plaque. Electron beam CT measures coronary calcium quickly, easily, accurately, and with a high degree of reproducibility. Coronary calcium is three to nine times higher in persons with fatal or nonfatal myocardial infarction than in age-matched controls, and four observational outcomes studies have demonstrated that the electron beam CT-derived coronary calcium score predicts fatal and nonfatal myocardial infarction. In symptomatic persons undergoing cardiac catheterization, electron beam CT is more closely associated with the severity of coronary atherosclerosis than are standard coronary risk factors. Preliminary evidence in asymptomatic persons indicates that the coronary calcium score also predicts coronary disease events more accurately than standard risk factors.
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Affiliation(s)
- A D Guerci
- St. Francis Hospital, 100 Port Washington Boulevard, Roslyn, NY 11576, USA.
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Arad Y, Newstein D, Roth M, Guerci A. Rationale and design of the St. Francis heart study: a randomized clinical trial of atorvastatin plus a antioxidants in asymptomatic persons with elevated coronary calcium. ATHEROSCLEROSIS SUPP 2001. [DOI: 10.1016/s1567-5688(01)80065-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
OBJECTIVES We sought to determine the prognostic accuracy of electron beam computed tomographic (EBCT) scanning of the coronary arteries at three to four years. BACKGROUND Coronary artery calcium scores determined by EBCT correlate with the severity of coronary artery disease. However, previous reports of the prognostic accuracy of EBCT scanning for coronary events in asymptomatic individuals are conflicting. METHODS Asymptomatic men and women undergoing coronary EBCT completed initial and follow-up evaluations, which included past medical history, the Rose angina questionnaire and interim cardiovascular events. Reported coronary events (death, nonfatal myocardial infarction [MI] and revascularization procedures) were confirmed without knowledge of the scan results. RESULTS Information was obtained in 1,172 (99.6%) of 1,177 eligible subjects (baseline age 53 +/- 11 years, 71% men). During an average follow-up of 3.6 years, 39 subjects sustained coronary events: three coronary deaths, 15 nonfatal MIs and 21 coronary artery revascularization procedures. The mean coronary artery calcium score was 764 +/- 935 among subjects with events as compared with 135 +/- 432 among those without events (p < 0.0001). For the prediction of all coronary events and of nonfatal MIs and deaths, the areas under the receiver-operator characteristics curve were 0.84 and 0.86, respectively, and a coronary calcium score > or =160 was associated with odds ratios of 15.8 and 22.2, respectively. The odds ratios for all events remained high (14.3 to 20.2) after adjustment for self-reported cardiovascular risk factors. CONCLUSIONS In asymptomatic adults, EBCT of the coronary arteries predicts coronary death and nonfatal MI and the need for revascularization procedures.
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Affiliation(s)
- Y Arad
- Department of Preventive Cardiology, St Francis Hospital, Roslyn, New York 11576, USA.
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Arad Y, Saxena U. Therapeutic strategies for coronary artery disease beyond low density lipoprotein (LDL)--lowering. Curr Pharm Des 1999; 5:1-10. [PMID: 10066880] [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: 02/11/2023]
Abstract
Coronary artery disease (CAD) ranks as the leading cause of death in the Western world. The most widely used therapeutics utilized for the treatment of CAD are the lipid-lowering drugs, which lower plasma cholesterol. However lowering cholesterol alone may not be sufficient to provide benefit to all patient populations at risk for CAD. This creates an unmet medical need. Emerging knowledge of the genesis, progression and regression of atherosclerosis, that leads to CAD permits evaluation of other therapeutic strategies. This review will evaluate two such naturally occurring paradigms, the nitric oxide pathway and the high-density lipoprotein system which are nature's defense mechanisms against atherosclerosis and may lead to next generation therapeutics against CAD.
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Affiliation(s)
- Y Arad
- Preventive Cardiology, St. Francis Hospital, Roslyn, New York 11576, USA
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Arad Y, Spadaro LA, Roth M, Scordo J, Goodman K, Sherman S, Lerner G, Newstein D, Guerci AD. Serum concentration of calcium, 1,25 vitamin D and parathyroid hormone are not correlated with coronary calcifications. An electron beam computed tomography study. Coron Artery Dis 1998; 9:513-8. [PMID: 9847983 DOI: 10.1097/00019501-199809080-00007] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The amount of coronary artery calcification, measured using electron beam computed tomography, is correlated with the volume of coronary artery atherosclerotic plaque, the severity of stenosis by angiography, and with the likelihood of future cardiovascular events. The deposition of calcium in atherosclerotic plaques may also be influenced by determinants of calcium metabolism, thus contributing to the variance of the relation between coronary artery calcification and extent of atherosclerosis. Our objective was to determine whether this variance could be explained by differences in the parameters of calcium metabolism. DESIGN AND METHODS We measured serum concentrations of calcium, 1,25(OH)2 vitamin D and parathyroid hormone (PTH) in 50 subjects undergoing angiography for clinical indications, and evaluated the correlations between these concentrations and calcium deposition in the coronary arteries, and the ratio of calcium deposition to extent of atherosclerosis using coronary angiography. RESULTS AND CONCLUSIONS Serum concentrations of calcium 1,25(OH)2 vitamin D and PTH were not correlated with coronary calcification or the ratio of coronary calcification to the extent of coronary stenosis. We conclude that, in subjects undergoing coronary angiography, the variance of the relationship between coronary atherosclerosis and coronary calcium is not a result of differences in serum concentrations of calcium, 1,25(OH)2 vitamin D or PTH.
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Affiliation(s)
- Y Arad
- Department of Preventive Cardiology, St Francis Hospital, Roslyn, New York 11576, USA.
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Guerci AD, Spadaro LA, Goodman KJ, Lledo-Perez A, Newstein D, Lerner G, Arad Y. Comparison of electron beam computed tomography scanning and conventional risk factor assessment for the prediction of angiographic coronary artery disease. J Am Coll Cardiol 1998; 32:673-9. [PMID: 9741510 DOI: 10.1016/s0735-1097(98)00299-x] [Citation(s) in RCA: 133] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To determine whether electron beam computed tomography (CT) adds to conventional risk factor assessment in the prediction of angiographic coronary artery disease. BACKGROUND Electron beam CT scanning can be used to predict the severity of coronary atherosclerosis, but whether it does so independently of conventional risk factors is unclear. METHODS Electron beam CT scans were performed and conventional risk factors were measured in 290 men and women undergoing coronary arteriography for clinical indications. The association of the electron beam CT-derived coronary artery calcium score and conventional risk factors with the presence and severity of angiographically defined coronary atherosclerosis was analyzed by logistic regression and receiver-operator characteristics analysis. RESULTS Age, the ratio of total cholesterol to high-density lipoprotein (HDL) cholesterol and the coronary calcium score were significantly and independently associated with the presence of any coronary disease and obstructive coronary disease. In association with any coronary disease, odds ratios for age, the ratio of total cholesterol to HDL cholesterol and calcium score, highest quartile vs. lowest quartile, were 6.01 (95% confidence interval 2.87 to 12.56), 3.14 (1.56 to 6.31) and 94.08 (21.06 to 420.12), respectively. For obstructive coronary disease, highest quartile vs. lowest quartile, the respective odds ratios for age, the ratio of total cholesterol to HDL and calcium score were 3.86 (1.86 to 8.00), 4.11 (1.98 to 8.52) and 34.12 (12.67 to 91.86). Male gender was also significantly associated with any coronary disease (odds ratio 2.19, p=0.04) and obstructive coronary disease (odds ratio 2.07, p=0.04). Cigarette smoking was significantly associated with any coronary disease (odds ratio=2.74, p=0.004), and diabetes was significantly associated with obstructive disease (odds ratio 3.16, p=0.01). After adjustment for the coronary calcium score and other risk factors, it was determined that triglycerides, family history and hypertension were not significantly associated with any disease state. A coronary calcium score >80 (Agatston method) was associated with an increased likelihood of any coronary disease regardless of the number of risk factors, and a coronary calcium score > or = 170 was associated with an increased likelihood of obstructive coronary disease regardless of the number of risk factors (p < 0.001). CONCLUSIONS Electron beam CT scanning offers improved discrimination over conventional risk factors in the identification of persons with any angiographic coronary disease or angiographic obstructive coronary disease.
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Affiliation(s)
- A D Guerci
- Research Department, St. Francis Hospital, Roslyn, New York 11576-1348, USA
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Abstract
We investigated the ability of NAC to inhibit in vitro LDL oxidation, and the effects of the timing of NAC addition, repeated additions of NAC, and the presence of preoxidized LDL, on the oxidation reaction. NAC inhibited in vitro LDL oxidation induced by copper sulfate, 2,2'-azobis(2-amidinopropane) dihydrochloride, and UV light, and protected LDL against depletion of antioxidant vitamins. Glutathione was similarly effective against copper-mediated LDL oxidation. NAC's effectiveness was inversely related to the timing of its addition. Sequential NAC additions prolonged the lag phase more effectively than initial addition of the same total dose. NAC reduced CD formation during the oxidation of native LDL by oxidized LDL. NAC's effectiveness as an inhibitor of in vitro LDL oxidation is dependent on the temporal sequence of the oxidation reaction, sequential additions, and the presence of previously oxidized LDL.
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Affiliation(s)
- A K Rattan
- St. Francis Hospital, DeMatteis Center, Lipid Research Laboratory, Roslyn, NY 11576-1348, USA
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Arad Y. Electron beam computed tomography for the diagnosis of cardiac disease. S Afr Med J 1998; 88:558-63. [PMID: 9638124] [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: 02/07/2023] Open
Abstract
Electron beam computed tomography (EBCT) of the heart is a new modality which will alter the way cardiology is practised. It allows for the detection of early coronary artery disease (CAD) in asymptomatic individuals, regardless of their level of risk as assessed by traditional risk factor analysis. Compared with risk analysis based on risk factors alone, an assessment which also utilises quantitative measurements of coronary artery plaque by EBCT allows for more precise determination of the need for medical therapy. Non-invasive intravenous contrast EBCT coronary angiography can identify significant obstructive CAD, and should reduce the need for conventional coronary angiography. Incorporation of EBCT into routine medical practice is more cost-effective than other modalities currently available. This paper reviews relevant original articles on EBCT and preventive cardiology published in peer-reviewed medical journals, and assesses the implications of EBCT for preventive cardiology.
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Affiliation(s)
- Y Arad
- Department of Preventive Cardiology, St Francis Hospital, Roslyn, NY, USA
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Arad Y, Spadaro LA, Roth M, Scordo J, Goodman K, Sherman S, Lledo A, Lerner G, Guerci AD. Correlations between vascular calcification and atherosclerosis: a comparative electron beam CT study of the coronary and carotid arteries. J Comput Assist Tomogr 1998; 22:207-11. [PMID: 9530380 DOI: 10.1097/00004728-199803000-00008] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [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: 02/07/2023]
Abstract
PURPOSE Electron beam CT (EBCT)-derived coronary artery calcium scores correlate with the extent of atherosclerosis, but there is a substantial variance about the general relationship between coronary calcification and coronary atherosclerosis. The relationship between calcification and atherosclerosis may also differ in various arteries. This study was designed to evaluate whether the relation between carotid artery intima-media thickness (IMT) and carotid artery calcium could be used as a correction factor to improve the correlation between coronary calcification and coronary atherosclerosis. METHOD We measured atherosclerosis in the coronary and carotid arteries by angiography and ultrasonography, respectively, and quantified coronary and carotid calcium deposition with EBCT in 50 subjects. The correlation between the findings in the carotid and coronary arteries was investigated. RESULTS Coronary artery calcium score correlated with coronary angiography and with carotid calcium score. Coronary stenosis correlated with carotid IMT. There was no meaningful correlation of carotid IMT and carotid calcium. CONCLUSION There is an intraindividual variation in the relationship of plaque mass to calcification among different vessels. The relation between carotid artery calcification and carotid IMT is not predictive of the relation between coronary artery calcification and coronary obstruction.
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Affiliation(s)
- Y Arad
- Department of Preventive Cardiology, St. Francis Hospital, Roslyn, NY 11576, USA
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Arad Y. Increased Coronary Calcification by EBCT Is Associated With Characteristics of Metabolic Syndrome X. J Am Coll Cardiol 1998. [DOI: 10.1016/s0735-1097(97)88287-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Abstract
Oxidation of low-density lipoprotein (LDL) is postulated to be essential for the development of atherosclerosis. LY-139478 is a new non-steroidal potent estrogen analog, but its effects on in vitro LDL oxidation have not been completely elucidated. We investigated the ability of LY-139478 to inhibit in vitro copper sulfate-mediated LDL oxidation using several methods, including conjugated diene (CD) accumulation, relative electrophoretic mobility on agarose gel, thiobarbituric acid-reactive substances (TBARS) assay, and superoxide anions scavenging activity. The antioxidative potential of LY-139478 was compared to testosterone (T), 17-alpha-estradiol (17alphaE), 17-beta-estradiol (17betaE), dehydroepiandrosterone (D), and dehydroepiandrosterone-3-sulfate (DS). LY-139478 was superior to 17alphaE and 17betaE in prolonging the lag phase and decreasing the slope and peak concentration of the conjugated diene accumulation, decreasing the rate of migration of LDL on agarose gel electrophoresis, and inhibiting the production of melonyldialdehyde (MDA) in the TBARS assay. T, D and DS were ineffective in all three assays. It was previously shown that when native LDL is oxidized by previously oxidized LDL (secondary oxidation) the lag phase is lost (Schnitzer et al. Free Rad Res 1995;23:137). LY-139478 was at least 15-fold more effective than 17alphaE, and 17betaE in slowing the propagation phase and reducing CD accumulation in this secondary oxidation, with 50% inhibition at 10 microM and 98% inhibition at 100 microM. However, none restored the lag phase. T, D and DS were ineffective. Superoxide anion generation was inhibited only by DS at high doses (500 microM). These results demonstrate that LY-139478 is an effective inhibitor of LDL oxidation and is superior to natural steroidal hormones, including 17betaE, in protecting against primary and secondary LDL oxidation.
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Affiliation(s)
- A K Rattan
- Department of Preventive Cardiology, St. Francis Hospital, Roslyn, NY 11576-1348, USA
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Arad Y, Roth M, Lerner G, Spadaro L, Guerci A. 4.P.44 Increased coronary calcification by Electron Beam CT is associated with insulin resistance, central and intra abdominal adiposity, and reduced HDL cholesterol. Atherosclerosis 1997. [DOI: 10.1016/s0021-9150(97)89571-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Arad Y, Spadaro LA, Goodman K, Lledo-Perez A, Sherman S, Lerner G, Guerci AD. Predictive value of electron beam computed tomography of the coronary arteries. 19-month follow-up of 1173 asymptomatic subjects. Circulation 1996; 93:1951-3. [PMID: 8640967 DOI: 10.1161/01.cir.93.11.1951] [Citation(s) in RCA: 347] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Coronary electron beam computed tomography (EBCT) detects atherosclerotic coronary artery disease by measuring calcium deposition in the walls of coronary arteries. EBCT-derived coronary artery calcium (CAC) scores correlate with the severity of underlying coronary artery disease. METHODS AND RESULTS We followed 1173 asymptomatic patients who underwent EBCT between September 1993 and March 1994. During average follow-up of 19 months, 18 subjects had 26 cardiovascular events: 1 death, 7 myocardial infarctions, 8 coronary artery bypass graft procedures, 9 coronary angioplasties, and 1 nonhemorrhagic stroke. For CAC score thresholds of 100, 160, and 680, EBCT had sensitivities of 89%, 89%, and 50% and specificities of 77%, 82%, and 95%, respectively. Odds ratios ranged from 20.0 to 35.4 (P < .0001 for all). CONCLUSIONS Coronary EBCT predicts future atherosclerotic cardiovascular disease events in asymptomatic subjects.
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Affiliation(s)
- Y Arad
- Department of Preventive Cardiology, St Francis Hospital, Roslyn, NY 11576, USA
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Galeano NF, Milne R, Marcel YL, Walsh MT, Levy E, Ngu'yen TD, Gleeson A, Arad Y, Witte L, Al-Haideri M, Rumsey SC, Deckelbaum RJ. Apoprotein B structure and receptor recognition of triglyceride-rich low density lipoprotein (LDL) is modified in small LDL but not in triglyceride-rich LDL of normal size. J Biol Chem 1994; 269:511-9. [PMID: 8276844] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We compared the effect of lipid composition and particle size of triglyceride-rich low density lipoprotein (LDL) upon apoprotein B conformation and binding to the LDL receptor. Three groups of triglyceride-rich LDL were studied: (a) LDL isolated from chronic hypertriglyceridemic individuals (HTG-LDL); (b) normal LDL made triglyceride-rich by in vitro incubation with triglyceride emulsion and the neutral lipid transfer protein (R-LDL); and (c) LDL from normolipidemic individuals made acutely hypertriglyceridemic by intravenous infusion of 10% Intralipid (IV-LDL). HTG-LDL was small and dense, whereas R-LDL and IV-LDL had normal size. HTG-LDL, but not R-LDL or IV-LDL, exhibited decreased binding to the LDL receptor on human skin fibroblasts in studies at 4 degrees C and reduced degradation at 37 degrees C. Apoprotein B conformation was assessed by circular dichroism and by analyzing the immunoreactivity of different monoclonal antibodies. HTG-LDL but not R-LDL or IV-LDL showed a change in the CD spectra and a consistent decrease in the immunoreactivity of monoclonal antibody 3F5 (2.5-fold) which recognizes an epitope adjacent to the receptor binding domain of apoprotein B. These findings suggest that in triglyceride-rich LDL, the relative content of neutral lipid in the core of LDL in the absence of changes in the size of the particle does not significantly affect apoprotein B conformation or its affinity for the LDL receptor.
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Affiliation(s)
- N F Galeano
- Department of Pediatrics, Columbia University, New York, New York 10032
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Galeano N, Milne R, Marcel Y, Walsh M, Levy E, Ngu'yen T, Gleeson A, Arad Y, Witte L, al-Haideri M. Apoprotein B structure and receptor recognition of triglyceride-rich low density lipoprotein (LDL) is modified in small LDL but not in triglyceride-rich LDL of normal size. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)42379-9] [Citation(s) in RCA: 133] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Rumsey SC, Galeano NF, Arad Y, Deckelbaum RJ. Cryopreservation with sucrose maintains normal physical and biological properties of human plasma low density lipoproteins. J Lipid Res 1992; 33:1551-61. [PMID: 1431579] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The ability to preserve low density lipoprotein (LDL) preparations frozen for weeks and months without changes in structure or biological properties is of potential use in long-term comparative studies of LDL. We demonstrate that freeze-thawing of LDL causes marked alterations in its structure and biological behavior, and that such changes can be prevented by the addition of sucrose to the LDL solution prior to freezing. Freezing LDL at -70 degrees C in the absence of sucrose resulted in aggregation and fusion of particles as measured by electron microscopy, spectrophotometric absorption, and column gel filtration. This was associated with increased binding affinity of monoclonal antibodies at epitopes distant from the receptor binding region. Functional changes induced by freezing included 3- to 10-fold increases in binding at 4 degrees C and 37 degrees C, and uptake of LDL in fibroblasts, attributable mainly to increases in nonspecific binding processes. Cryopreservation of LDL in 10% sucrose (w/v) completely prevented the structural and functional changes incurred after short-term freezing, and LDL cryopreserved in sucrose for as long as 18 months displayed cell binding, uptake, and degradation very similar to that of freshly obtained LDL.
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Affiliation(s)
- S C Rumsey
- Department of Pediatrics, Columbia University, New York, NY 10032
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Rumsey SC, Galeano NF, Arad Y, Deckelbaum RJ. Cryopreservation with sucrose maintains normal physical and biological properties of human plasma low density lipoproteins. J Lipid Res 1992. [DOI: 10.1016/s0022-2275(20)41409-9] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Rumsey SC, Obunike JC, Arad Y, Deckelbaum RJ, Goldberg IJ. Lipoprotein lipase-mediated uptake and degradation of low density lipoproteins by fibroblasts and macrophages. J Clin Invest 1992; 90:1504-12. [PMID: 1401083 PMCID: PMC443197 DOI: 10.1172/jci116018] [Citation(s) in RCA: 153] [Impact Index Per Article: 4.8] [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: 12/26/2022] Open
Abstract
Lipoprotein lipase (LPL), the rate limiting enzyme for hydrolysis of lipoprotein triglyceride, also mediates nonenzymatic interactions between lipoproteins and heparan sulfate proteoglycans. To determine whether cell surface LPL increases LDL binding to cells, bovine milk LPL was added to upregulated and nonupregulated human fibroblasts along with media containing LDL. LDL binding to cells was increased 2-10-fold, in a dose-dependent manner, by the addition of 0.5-10 micrograms/ml of LPL. The amount of LDL bound to the cells in the presence of LPL far exceeded the capacity for LDL binding via the LDL receptor. Treatment of fibroblasts with heparinase and heparitinase resulted in a 64% decrease in LPL-mediated LDL binding. Compared to studies performed without LPL, more LDL was internalized and degraded in the presence of LPL, but the time course was slower than that of classical lipoprotein receptor mediated pathways. In LDL receptor negative fibroblasts, LPL increased surface bound LDL > 140-fold, intracellular LDL > 40-fold, and LDL degradation > 6-fold. These effects were almost completely inhibited by heparin and anti-LPL monoclonal antibody. LPL also increased the binding and uptake by fibroblasts of apolipoprotein-free triglyceride emulsions; binding was increased > 8-fold and cellular uptake was increased > 40-fold with LPL. LPL increased LDL binding to THP-1 monocytes, and increased LDL uptake (4.5-fold) and LDL degradation (2.5-fold) by THP-1 macrophages. In the absence of added LPL, heparin and anti-LPL monoclonal antibodies decreased LDL degradation by > 40%, and triglyceride emulsion uptake by > 50%, suggesting that endogenously produced LPL mediated lipid particle uptake and degradation. We conclude that LPL increases lipid and lipoprotein uptake by cells via a pathway not involving the LDL receptor. This pathway may be important for lipid accumulation in LPL synthesizing cells.
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Affiliation(s)
- S C Rumsey
- Department of Pediatrics, Columbia University College of Physicians and Surgeons, New York 10032
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Arad Y, Ramakrishnan R, Ginsberg HN. Effects of lovastatin therapy on very-low-density lipoprotein triglyceride metabolism in subjects with combined hyperlipidemia: evidence for reduced assembly and secretion of triglyceride-rich lipoproteins. Metabolism 1992; 41:487-93. [PMID: 1588827 DOI: 10.1016/0026-0495(92)90206-p] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have previously reported decreased production rates of the major apolipoprotein B (apoB)-containing lipoproteins, very-low-density lipoproteins (VLDL), and low-density lipoproteins (LDL) in patients with combined hyperlipidemia (CHL) during treatment with lovastatin. In the present study, we determined the effects of lovastatin therapy on VLDL triglyceride (TG) metabolism. Plasma VLDL turnover was determined in six CHL patients, before and during lovastatin therapy. 3H-triglyceride-glycerol-specific activity data derived from injection of 3H-glycerol were analyzed by compartmental modeling. The effects of lovastatin on VLDL TG metabolism were compared with those previously determined on VLDL apoB metabolism in these subjects. Lovastatin therapy was associated with decreased concentrations of VLDL TG in five of six patients and decreased VLDL apoB concentrations in all six. VLDL TG production rates (PR) decreased in five patients, with the mean for the group decreasing from 14.1 +/- 7.1 to 10.3 +/- 4.0 mg/kg/h (P less than .05). VLDL apoB PR also decreased in five patients, with the mean decreasing from 21.8 +/- 20.3 to 12.2 +/- 9.0 mg/kg/d (P = .11). Changes in VLDL TG concentrations during lovastatin treatment were correlated with changes in VLDL apoB concentrations (r = .74, P = .09) and in VLDL TG PR (r = .91, P = .01). Changes in VLDL TG PR were also related to changes in VLDL apoB PR (r = .62, P = NS). There were no consistent changes in the fractional catabolic rates of either VLDL TG or VLDL apoB during lovastatin therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- Y Arad
- Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY 10032
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Ramakrishnan R, Arad Y, Wong S, Ginsberg HN. Nonuniform radiolabeling of VLDL apolipoprotein B: implications for the analysis of studies of the kinetics of the metabolism of lipoproteins containing apolipoprotein B. J Lipid Res 1990; 31:1031-42. [PMID: 2373953 PMCID: PMC3275143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Radiolabeling of whole lipoproteins or individual apolipoproteins has been an essential tool for the determination of the kinetics of apolipoprotein metabolism in vivo. Mathematical analysis of specific radioactivity (SA) or total radioactivity data has demonstrated the existence of significant complexity in the plasma decay curves of several apolipoproteins. Results obtained during development of methods to study the metabolism of apolipoprotein B (apoB) in very low density lipoprotein (VLDL) subclasses isolated according to flotation (Sf) rates from whole radiolabeled (d less than 1.006 g/ml) VLDL suggested nonuniform radiolabeling of apoB in the three Sf subclasses being studied. We therefore determined apoB SA in VLDL Sf subclasses in ten hypertriglyceridemic and five normal subjects. After radioiodination of apoB in whole VLDL, different apoB SA were found in Sf 400-100, Sf 100-60, and Sf 60-20. The pattern of labeling was quite variable among subjects. On average, apoB SA in the VLDL tracer was greatest in Sf 400-100, and least in Sf 60-20. Nonuniform labeling could also be demonstrated in five studies in which samples were obtained 3 min after intravenous injection of the tracer into subjects with a wide range of plasma triglycerides. Nonuniform labeling of apoB in whole VLDL was also demonstrated in two of the subjects by isolating subclasses of their VLDL that did not bind to an anti-apolipoprotein E immunoaffinity column. These results indicate that the usual assumption of homogeneous labeling of apoB may be erroneous. We have derived a simple mathematical formula to study the consequences of this assumption in estimating kinetic parameters. It is shown that an erroneous assumption of homogeneous tracer labeling may significantly underestimate or overestimate the true production rate, even in a simple two-pool model. Identification of labeling characteristics and incorporation of this information into the mathematical analysis of the plasma radioactivity data can improve the accuracy of the analysis as well as the sensitivity of compartmental models generated by such data.
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Affiliation(s)
- R Ramakrishnan
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032
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Usiskin KS, Butterworth S, Clore JN, Arad Y, Ginsberg HN, Blackard WG, Nestler JE. Lack of effect of dehydroepiandrosterone in obese men. Int J Obes (Lond) 1990; 14:457-63. [PMID: 2143499] [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] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
To assess the effects of dehydroepiandrosterone (DHEA) on weight and body fat mass in young obese men, six obese (body mass index, 31.5 +/- 2.9 (s.e.] men were studied at baseline, after 28 days of placebo administration, and again after 28 days of DHEA (1600 mg/day) administration. Body fat mass was assessed on each occasion by three separate methods: hydrostatic weighing, impedance plethysmography, and skinfold measurements at four body sites. Waist-to-hip ratios were recorded. In addition, tissue sensitivity to insulin was determined using the modified minimal model technique, and serum lipids were assayed. Serum DHEA-sulfate levels rose from 7.4 +/- 1.7 mumol/l at baseline to 39.8 +/- 11.9 mumol/l after DHEA administration (P less than 0.05). Although body fat mass was reduced in two of the six men following DHEA administration, for the group as a whole neither total body weight, body fat mass, or waist-to-hip ratio changed significantly during the study. No change in either tissue insulin sensitivity or serum lipids was observed. These observations suggest that, at a daily dose of 13.4-19.7 mg/kg, short-term DHEA administration does not affect the total weight, body fat mass, fat distribution, insulin sensitivity, or lipid status of obese young men.
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Affiliation(s)
- K S Usiskin
- Department of Medicine, Medical College of Virginia/Virginia Commonwealth University, Richmond 23298
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Arad Y, Ramakrishnan R, Ginsberg HN. Lovastatin therapy reduces low density lipoprotein apoB levels in subjects with combined hyperlipidemia by reducing the production of apoB-containing lipoproteins: implications for the pathophysiology of apoB production. J Lipid Res 1990; 31:567-82. [PMID: 2351867] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
We investigated the metabolism of very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), and low density lipoprotein (LDL) apolipoprotein B (apoB) in seven patients with combined hyperlipidemia (CHL), using 125I-labeled VLDL and 131I-labeled LDL and compartmental modeling, before and during lovastatin treatment. Lovastatin therapy significantly reduced plasma levels of LDL cholesterol (142 vs 93 mg/dl, P less than 0.0005) and apoB (1328 vs 797 micrograms/ml, P less than 0.001). Before treatment, CHL patients had high production rates (PR) of LDL apoB. Three-fourths of this LDL apoB flux was derived from sources other than circulating VLDL and was, therefore, defined as "cold" LDL apoB flux. Compared to baseline, treatment with lovastatin was associated with a significant reduction in the total rate of entry of apoB-containing lipoproteins into plasma in all seven CHL subjects (40.7 vs. 25.7 mg/kg.day, P less than 0.003). This reduction was associated with a fall in total LDL apoB PR and in "cold" LDL apoB PR in six out of seven CHL subjects. VLDL apoB PR fell in five out of seven CHL subjects. Treatment with lovastatin did not significantly alter VLDL apoB conversion to LDL apoB or LDL apoB fractional catabolic rate (FCR) in CHL patients. In three patients with familial hypercholesterolemia who were studied for comparison, lovastatin treatment increased LDL apoB FCR but did not consistently alter LDL apoB PR. We conclude that lovastatin lowers LDL cholesterol and apoB concentrations in CHL patients by reducing the rate of entry of apoB-containing lipoproteins into plasma, either as VLDL or as directly secreted LDL.
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Affiliation(s)
- Y Arad
- Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY 10032
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Arad Y, Badimon JJ, Badimon L, Hembree WC, Ginsberg HN. Dehydroepiandrosterone feeding prevents aortic fatty streak formation and cholesterol accumulation in cholesterol-fed rabbit. Arteriosclerosis 1989; 9:159-66. [PMID: 2522296 DOI: 10.1161/01.atv.9.2.159] [Citation(s) in RCA: 100] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The concentration of dehydroepiandrosterone sulfate (DHEA-S) in human plasma is higher than any other steroid. Recent evidence has suggested an inverse relationship between plasma DHEA levels and the development of coronary atherosclerosis in humans. We used the cholesterol-fed rabbit model to investigate whether DHEA feeding would diminish aortic fatty streak formation in this model. Fifteen New Zealand White rabbits were fed rabbit chow supplemented with 0.5% cholesterol (wt/wt). Seven animals were, in addition, fed DHEA, 0.5% of diet (wt/wt). Animals were sacrificed after 2 months, and the aortic involvement with fatty streaks was evaluated by computerized planimetry of Sudan IV-stained aortas and by chemical analysis of aortic wall lipids. Compared to controls, DHEA-fed animals had similar plasma levels of total, very low density lipoprotein (VLDL), low density lipoprotein (LDL), and high density lipoprotein (HDL) cholesterol, corticoids, and estrogens. DHEA-fed animals had higher plasma levels of total, VLDL, and LDL triglycerides and lower HDL triglycerides than did controls. DHEA feeding resulted in 30% and 40%, respectively, inhibition of fatty streak formation by chemical analysis and planimetry. We conclude that DHEA feeding inhibits the development of aortic fatty streaks in cholesterol-fed rabbits, independent of changes in plasma total and LDL cholesterol levels of DHEA conversion to estrogens or corticoids.
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Affiliation(s)
- Y Arad
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY 10032
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Abstract
Isoelectric focusing on thin layers of agarose was used to separate several human hemoglobin variants in narrow pH range (pH 6-9). Problems with gel flooding and distortions due to electroendosmotic flow were solved by altering the casting and processing of the gel, by modifying the focusing apparatus, and by utilizing commercial agarose that had been chemically modified to reduce electroendomosis. Hemoglobins C, O-ARAB, A2, and E were distinguished from one another, as were hemoglobins S, D-LOS ANGELES, G-PHILADELPHIA, F. A, I, and J. The technic is rapid, simple, and relatively inexpensive. The agarose is nontoxic, has excellent gelling properties, and possesses large pores, yet gives resolution equivalent or superior to that obtained on thin layers of polyacrylamide gel, making it preferable to polyacrylamide for thin-layer isoelectric focusing.
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