Jan Breslow | |
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Alma mater | |
Awards | Heinrich Wieland Prize (1991) |
Scientific career | |
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Jan Leslie Breslow (born 1943) [1] [2] is an American physician and medical researcher who studies atherosclerosis. As of 2017, he is Frederick Henry Leonhardt Professor at Rockefeller University and directs the university's Laboratory of Biochemical Genetics and Metabolism.
Breslow attended Columbia College, Columbia University, gaining AB (1963) and MA (1964) degrees in chemistry. He then studied at Harvard Medical School, receiving his MD in 1968. He worked in pediatric medicine at the Boston Children's Hospital (1968–70) and then held a post-doctoral position at the National Heart, Lung, and Blood Institute (1970–73). [1] [3]
In 1973, he took up a post as head of the metabolism division of Boston Children's Hospital, as well as successively instructor, assistant and associate professor in pediatric medicine at Harvard Medical School. In 1984, he moved to Rockefeller University as a professor, and in 1986, was appointed Frederick Henry Leonhardt Professor at the Laboratory of Biochemical Genetics and Metabolism. [1] [3] In 2014, he was appointed director of the university's Sackler Center for Biomedicine and Nutrition. [3] He also works at Rockefeller University Hospital as a senior physician and was physician-in-chief in the 1990s. [1] [3]
Breslow's research has focused on the genetic factors that govern an individual's predisposition to develop atherosclerosis. [4] He started to work on the genetics of cholesterol handling in the late 1970s, [5] and in the early 1980s, with Vassilis Zannis, he was one of the earliest to dissect the different variants of human apolipoprotein E (ApoE), a component of very low-density lipoprotein. [6] People with different ApoE variants are now known to have different risks not only of heart disease but also of Alzheimer's disease. [4] In 1992, his group found that deleting the mouse gene for ApoE caused the animals to develop elevated blood cholesterol levels and atherosclerosis within around 6 months, on a normal diet. [7] Nobuyo Maeda's group at the University of North Carolina at Chapel Hill also independently created ApoE knockouts (apoe−/−) that developed atherosclerosis at the same time. [8] [9] [10] The ApoE knockout was the earliest mouse model of the disease, and has been widely used in atherosclerosis research. [10] [11] [12]
His group has subsequently researched other genes associated with atherosclerosis, and for example, in 2003, were among the first to identify and characterize PCSK9 , which encodes an enzyme acting in a novel cholesterol regulatory pathway. [13] Antibodies targeting PCSK9 were approved by the US FDA as a novel class of cholesterol-lowering drugs in 2015. [14]
Breslow is an elected fellow of the American Society for Clinical Investigation (1984), [2] US National Academy of Sciences (1995), Deutsche Akademie der Naturforscher Leopoldina (1996) [15] and the Institute of Medicine (1997). [4] He served as president of the American Heart Association – using the position to lobby vigorously for more government funding for research into heart disease [16] – and has received several awards from the association, including their Lifetime Research Achievement Award in 2010. [1] He has also served as vice president of the American Society for Clinical Investigation. [4] He has won the E. Mead Johnson Award of the American Academy of Pediatrics (1984), the Heinrich Wieland Prize (1991) and the Bristol-Myers Squibb Award for Cardiovascular Research (2000). [1] [4] In March 2013, Rockefeller University organized a symposium entitled "Genetics of Lipid Disorders and Atherosclerosis" to mark his seventieth birthday. [17]
Breslow is married to Marilyn G. Breslow, an investment manager and sculptor; the couple have two sons. [18] [19] Breslow is one of the signatories of a letter entitled "No Need to Panic About Global Warming", which was published in The Wall Street Journal in 2012. [20]
Low-density lipoprotein (LDL) is one of the five major groups of lipoprotein that transport all fat molecules around the body in extracellular water. These groups, from least dense to most dense, are chylomicrons, very low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), low-density lipoprotein (LDL) and high-density lipoprotein (HDL). LDL delivers fat molecules to cells. LDL has been associated with the progression of atherosclerosis.
A lipoprotein is a biochemical assembly whose primary function is to transport hydrophobic lipid molecules in water, as in blood plasma or other extracellular fluids. They consist of a triglyceride and cholesterol center, surrounded by a phospholipid outer shell, with the hydrophilic portions oriented outward toward the surrounding water and lipophilic portions oriented inward toward the lipid center. A special kind of protein, called apolipoprotein, is embedded in the outer shell, both stabilising the complex and giving it a functional identity that determines its role.
Hypercholesterolemia, also called high cholesterol, is the presence of high levels of cholesterol in the blood. It is a form of hyperlipidemia, hyperlipoproteinemia, and dyslipidemia.
Joseph Leonard Goldstein ForMemRS is an American biochemist. He received the Nobel Prize in Physiology or Medicine in 1985, along with fellow University of Texas Southwestern researcher, Michael Brown, for their studies regarding cholesterol. They discovered that human cells have low-density lipoprotein (LDL) receptors that remove cholesterol from the blood and that when LDL receptors are not present in sufficient numbers, individuals develop hypercholesterolemia and become at risk for cholesterol related diseases, notably coronary heart disease. Their studies led to the development of statin drugs.
Apolipoproteins are proteins that bind lipids to form lipoproteins. They transport lipids in blood, cerebrospinal fluid and lymph.
Hyperlipidemia is abnormally high levels of any or all lipids or lipoproteins in the blood. The term hyperlipidemia refers to the laboratory finding itself and is also used as an umbrella term covering any of various acquired or genetic disorders that result in that finding. Hyperlipidemia represents a subset of dyslipidemia and a superset of hypercholesterolemia. Hyperlipidemia is usually chronic and requires ongoing medication to control blood lipid levels.
The low-density lipoprotein receptor (LDL-R) is a mosaic protein of 839 amino acids that mediates the endocytosis of cholesterol-rich low-density lipoprotein (LDL). It is a cell-surface receptor that recognizes apolipoprotein B100 (ApoB100), which is embedded in the outer phospholipid layer of very low-density lipoprotein (VLDL), their remnants—i.e. intermediate-density lipoprotein (IDL), and LDL particles. The receptor also recognizes apolipoprotein E (ApoE) which is found in chylomicron remnants and IDL. In humans, the LDL receptor protein is encoded by the LDLR gene on chromosome 19. It belongs to the low density lipoprotein receptor gene family. It is most significantly expressed in bronchial epithelial cells and adrenal gland and cortex tissue.
Apolipoprotein E (Apo-E) is a protein involved in the metabolism of fats in the body of mammals. A subtype is implicated in Alzheimer's disease and cardiovascular diseases. It is encoded in humans by the gene APOE.
Apolipoprotein B (ApoB) is a protein that in humans is encoded by the APOB gene. Its measurement is commonly used to detect risk of atherosclerotic cardiovascular disease.
Familial hypercholesterolemia (FH) is a genetic disorder characterized by high cholesterol levels, specifically very high levels of low-density lipoprotein cholesterol, in the blood and early cardiovascular diseases. The most common mutations diminish the number of functional LDL receptors in the liver or produce abnormal LDL receptors that never go to the cell surface to function properly. Since the underlying body biochemistry is slightly different in individuals with FH, their high cholesterol levels are less responsive to the kinds of cholesterol control methods which are usually more effective in people without FH. Nevertheless, treatment is usually effective.
Lipoprotein(a) is a low-density lipoprotein variant containing a protein called apolipoprotein(a). Genetic and epidemiological studies have identified lipoprotein(a) as a risk factor for atherosclerosis and related diseases, such as coronary heart disease and stroke.
Apolipoprotein AI(Apo-AI) is a protein that in humans is encoded by the APOA1 gene. As the major component of HDL particles, it has a specific role in lipid metabolism.
Apolipoprotein C-III also known as apo-CIII, and apolipoprotein C3, is a protein that in humans is encoded by the APOC3 gene. Apo-CIII is secreted by the liver as well as the small intestine, and is found on triglyceride-rich lipoproteins such as chylomicrons, very low density lipoprotein (VLDL), and remnant cholesterol.
ATP-binding cassette transporter ABCA1, also known as the cholesterol efflux regulatory protein (CERP) is a protein which in humans is encoded by the ABCA1 gene. This transporter is a major regulator of cellular cholesterol and phospholipid homeostasis.
Apolipoprotein A-V is a protein that in humans is encoded by the APOA5 gene on chromosome 11. It is significantly expressed in liver. The protein encoded by this gene is an apolipoprotein and an important determinant of plasma triglyceride levels, a major risk factor for coronary artery disease. It is a component of several lipoprotein fractions including VLDL, HDL, chylomicrons. It is believed that apoA-V affects lipoprotein metabolism by interacting with LDL-R gene family receptors. Considering its association with lipoprotein levels, APOA5 is implicated in metabolic syndrome. The APOA5 gene also contains one of 27 SNPs associated with increased risk of coronary artery disease.
Apolipoprotein A-II is a protein that in humans is encoded by the APOA2 gene. It is the second most abundant protein of the high density lipoprotein particles. The protein is found in plasma as a monomer, homodimer, or heterodimer with apolipoprotein D. ApoA-II regulates many steps in HDL metabolism, and its role in coronary heart disease is unclear. Remarkably, defects in this gene may result in apolipoprotein A-II deficiency or hypercholesterolemia.
Proprotein convertase subtilisin/kexin type 9 (PCSK9) is an enzyme encoded by the PCSK9 gene in humans on chromosome 1. It is the 9th member of the proprotein convertase family of proteins that activate other proteins. Similar genes (orthologs) are found across many species. As with many proteins, PCSK9 is inactive when first synthesized, because a section of peptide chains blocks their activity; proprotein convertases remove that section to activate the enzyme. The PCSK9 gene also contains one of 27 loci associated with increased risk of coronary artery disease.
Alirocumab, sold under the brand name Praluent, is a medication used as a second-line treatment for high cholesterol for adults whose cholesterol is not controlled by diet and statin treatment. It is a human monoclonal antibody that belongs to a novel class of anti-cholesterol drugs, known as PCSK9 inhibitors, and it was the first such agent to receive FDA approval. The FDA approval was contingent on the completion of further clinical trials to better determine efficacy and safety.
Apabetalone is an orally available small molecule created by Resverlogix Corp. that is being evaluated in clinical trials for the treatment of atherosclerosis and associated cardiovascular disease (CVD). In the phase II clinical trial ASSURE in patients with angiographic coronary disease and low high-density lipoprotein cholesterol (HDL-C) levels, apabetalone showed no greater increase in HDL-cholesterol (HDL-c) and apolipoprotein A-I (ApoA-I) levels or incremental regression of atherosclerosis than administration of placebo, while causing a statistically significant greater incidence of elevated liver enzymes. However, pooled analysis of the effect of apabetalone in three phase II clinical trials ASSERT, ASSURE, and SUSTAIN demonstrated increases in HDL-cholesterol (HDL-c) and apolipoprotein A-I (ApoA-I) levels, as well as decreases in the incidence of major adverse cardiac events (MACE). Reduction of MACE was more profound in patients with diabetes mellitus. In a short-term study in prediabetics, favorable changes in glucose metabolism were observed in patients receiving apabetalone. An international, multicenter phase III trial, “Effect of RVX000222 on Time to Major Adverse Cardiovascular Events in High-Risk Type 2 Diabetes Mellitus Subjects with Coronary Artery Disease” (BETonMACE) commenced in October 2015. The trial is designed to determine whether apabetalone in combination with statins can decrease cardiac events compared to treatment with statins alone.
Nobuyo N. Maeda is a Japanese geneticist and medical researcher, who works on complex human diseases including atherosclerosis, diabetes and high blood pressure, and is particularly known for creating the first mouse model for atherosclerosis. Maeda has worked in the United States since 1978; as of 2017, she is the Robert H. Wagner Distinguished Professor at the University of North Carolina at Chapel Hill.