* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Berman - LIFE at UCF - University of Central Florida
Neurogenomics wikipedia , lookup
Perivascular space wikipedia , lookup
Cognitive flexibility wikipedia , lookup
Neuropsychology wikipedia , lookup
Molecular neuroscience wikipedia , lookup
Haemodynamic response wikipedia , lookup
Neuropsychopharmacology wikipedia , lookup
Neurophilosophy wikipedia , lookup
Environmental enrichment wikipedia , lookup
Visual selective attention in dementia wikipedia , lookup
Cognitive science wikipedia , lookup
Embodied cognitive science wikipedia , lookup
Cognitive neuroscience wikipedia , lookup
Nutrition and cognition wikipedia , lookup
Aging brain wikipedia , lookup
Dementia with Lewy bodies wikipedia , lookup
Impact of health on intelligence wikipedia , lookup
Clinical neurochemistry wikipedia , lookup
Stephen A Berman MD PhD University of Central Florida College of Medicine Clarifying some basic terminology Dementia is a general term for loss of cognitive functions, i.e. thinking abilities. Alzheimer’s Disease, as routinely used in the medical literature, is a particular type of dementia. Alois Alzheimer b. 6/14/1864 First Known Case of Alzheimer’s Disease Auguste D. Alois Alzheimer b. 6/14/1864 • “Auguste D.”, a 51 y/o woman. • Delusions that her husband was having an affair. • Soon followed by rapidly progressive memory loss, losing her way in the apartment, carrying/hiding household objects, worsening paranoia. Alzheimer’s Disease NFT’s (silver stain) Cortical atrophy Plaque (silver stain) Tangle (silver stain) 1898 Recent studies on dementia senilis and brain disorders caused by atheromatous vascular disease: by A. Alzheimer 1901-1906 Alzheimer treated and followed Auguste D. 1906 Lecture on Auguste D.’s case 1910 Emil Kraepelin coins term Alzheimer’s Disease (both Alzheimer’s and Kraepelin had reservations concerning whether it was a “disease” or just a premature aging of the brain. 1970’s Alzheimer’s disease recognized but considered relatively rare. 1975- Dr. Robert Butler—NIA. Alzheimer’s is the major cause of cognitive impairment in the Elderly. With sufficient application of money, we can cure it in 5 years! 1981-Ann Neurol. 1981 Aug;10(2):122-6. Alzheimer disease: evidence for selective loss of cholinergic neurons in the nucleus basalis. Whitehouse PJ, Price DL, Clark AW, Coyle JT, DeLong MR. Donepezil (Aricept): all stages of Alzheimer's. Rivastigmine (Exelon): mild to moderate Alzheimer's. Galantamine (Razadyne): mild to moderate Alzheimer's. 2014- Alzheimer’s Disease: the Scientific Holy War Amyloid Plaque (beta amyloid protein or BAP) Neurofibrillary Tangle (tau protein) • BAPtists: The accumulation of a fragment of the beta amyloid precursor (BAP) protein or APP (the amyloid beta 42 residue fragment or Ab-42) leads to the formation of plaques that someone kill neurons. • TAUists: Abnormal phosphorylation of tau proteins makes them “sticky,” leading to the break up of microtubules. The resulting loss of axonal transport causes cell death. Ann Neurol. 1981 Aug;10(2):122-6. Alzheimer disease: evidence for selective loss of cholinergic neurons in the nucleus basalis. Whitehouse PJ, Price DL, Clark AW, Coyle JT, DeLong MR. Most of what we call Alzheimer’s Disease is essentially aging of the brain. Some people’s brains age faster in this manner…others age slower. Numerous factors influence this process including general health, cardiovascular health, sleep, exercise, relaxation vs. stress, diet, and heredity. Some tests may measure certain substances that correlate with or predict this process but that does not prove we are dealing with a singular disease—or even a multifactorial disease as we usually think about it. Myth Closer to Reality Alzheimer’s is a disease Alzheimer’s is a complex cluster of multi-factorial, multi-level brain problems typically seen with aging “AD ravages the brain” “Brain aging creates age-associated cognitive challenges” “AD leads to a loss of self” “Brain aging creates a change in self” “Alzheimer's is a slow death” Even WITH a diagnosis of AD, “Aging persons can still be vital contributors” We must declare war on Alzheimer’s We should better understand the aging process, particularly as applied to the nervous system So what is Alzheimer’s disease? Short answer: I don’t know Longer answer: A word describing a cluster of multiple problems at multiple levels of the nervous system which can give rise to a gradual decline in our ability to think. If you want, you may call that a disease, but if so it probably is not a disease that will respond to a single type of treatment. Anti-Alzheimmab Berman Pharmaceuticals Ltd Alzheimer’s: A Multi-level Multi Factorial Problems Associated with Aging ? Cell types Proteins Intracellular Structures Affect Supracellular structures Affected Other bodily systems Neurons (beta) amyloid Mitochondria Data Streams Cardiovascular Tubulin Lysosomes Networks Endocrine Proteases (calpains) Proteasome Connectome (or parts thereof) Ubiquitin Glia, and Microglia Proteases (calpains) Mitochondria Ubiquitin Lysosomes Neurofilament protein Proteosomes teleomeres Weakness With Aging Muscle Disease—Adult Muscular Dystrophies, Myasthenia Gravis, Polymyositis, etc. Nerve Disease---Diabetic, Hereditary (e.g. Charcot-Marie-Toothe Disease), etc. Nerve Root Injury---Disc problems, infections Spinal Cord Problems Weakness due to aging per se Thinking Problems With Aging Strokes Hereditary Diseases—Huntington’s, Lewy Body Disease, Fronto-Temporal Dementia, Normal Pressure Hydrocephalus, Progressive Supranuclear Palsy, Corticobasilar atrophy Brain trauma Brain tumors Effects of Aging on the brain =? Alzheimer’s Disease ? Neurodegenerative Disorders - Part 2 Neurodegenerative disorders, Oriented toward Dementia/neurocognitive disorders (e.g. Alzheimer’s disease) Stephen Berman MD PHD Professor of Neurology UCF Spongiform changes of the brain Spongiform changes Amyloid plaque INCLUSIONS Disease Inclusions Protein Associated proteins Parkinsons Lewy body α-synuclein ? Lewy Body Disease Lewy body α-synuclein ? Alzheimers Amyloid Plaque, NF Tangle β- amyloid fragments , abnormal Tau APP, presenilin, secretases, Tau positive glial inclusions Tau Tau Fronto Temporal Dementia, (also Progressive Supranuclear Palsy, Corticobasilar Degeneration) Huntington’s Nuclear and Huntintin cytoplasmic inclusions Huntintin SCA Ataxin Ataxin ALS SOD1 NF-H Prion Prion CJD Amyloid plaque, spongiform changes Objectives • The objectives of this session are to understand and learn about concepts, ideas, and facts related to neurodegenerative diseases. These include the following: • • • • General features Pathological hallmarks Genetic and molecular biological factors Biochemical Mechanisms DEMENTIA Causes Alzheimer's disease* Vascular dementia* Fronto-temporal dementia Parkinson's disease with dementia Lewy body dementia Progressive supranuclear palsy (PSP) Normal pressure hydrocephalus Creutzfeldt-Jacob Disease Huntington's disease Others * We will focus on the problems marked with an asterix Working Definition of Dementia Acquired disorder Decline from premorbid baseline Affects at least 2 cognitive functions Is a syndrome more than a diagnosis Some forms of dementia leave memory intact Previously called “hardening of the arteries” or “senility” DSM IV Diagnosis of Dementia Memory impairment [insidious onset, gradual progression] AND Impairment in at least 1 other cognitive domain Affecting social or occupational function (“activities of daily living” – ADLs) Represents a decline from pre-morbid ability DSM-5: Minor Neurocognitive disorder Diagnostic Criteria A. Evidence of modest cognitive decline from a previous level of performance in one or more cognitive domains (complex attention, executive function, learning and memory, language, perceptual-motor, or social cognition) based on: 1. Concern of the individual, a knowledgeable informant, or the clinician that there has been a mild decline in cognitive function; and 2. A modest impairment in cognitive performance, preferably documented by standardized neuropsychological testing or, in its absence, another quantified clinical assessment. B. The cognitive deficits do not interfere with capacity for independence in everyday activities (i.e., complex instrumental activities of daily living such as paying bills or managing medications are preserved, but greater effort, compensatory strategies, or accommodation may be required). C. The cognitive deficits do not occur exclusively in the context of a delirium. D. The cognitive deficits are not better explained by another mental disorder (e.g., major depressive disorder, schizophrenia). DSM-5: Major Neurocognitive disorder Diagnostic Criteria A. Evidence of significant cognitive decline from a previous level of performance in one or more cognitive domains (complex attention, executive function, learning and memory, language, perceptual-motor, or social cognition) based on: 1. Concern of the individual, a knowledgeable informant, or the clinician that there has been a significant decline in cognitive function; and 2. A substantial impairment in cognitive performance, preferably documented by standardized neuropsychological testing or, in its absence, another quantified clinical assessment. B. The cognitive deficits interfere with independence in everyday activities (i.e., at a minimum, requiring assistance with complex instrumental activities of daily living such as paying bills or managing medications). C. The cognitive deficits do not occur exclusively in the context of a delirium. D. The cognitive deficits are not better explained by another mental disorder (e.g., major depressive disorder, schizophrenia). Important Issues Dementia is an important public health problem that is increasing. The diagnosis of dementia is still clinical but new methods are emerging. Etiology is probably related to toxic beta amyloid fragments, neurofibrillary tangles and problems caused by other proteins. Acetylcholine is especially affected in Alzheimer’s disease and Lewey Body Disease. Current treatments are effective, but palliative. First line: acetylcholinesterase inhibitors. Alzheimer’s Disease: the Scientific Holy War The Baptists vs. The Tauists • BAPtists: The accumulation of a fragment of the beta amyloid precursor (BAP) protein or APP (the amyloid beta 42 residue fragment or Ab-42) leads to the formation of plaques that someone kill neurons. • TAUists: Abnormal phosphorylation of tau proteins makes them “sticky,” leading to the break up of microtubules. The resulting loss of axonal transport causes cell death. Amyloid Hypothesis 1. The amyloid precursor protein (APP) is broken down by “secretases” 2. A nonsoluble fragment of the APP protein (mostly Ab-42) accumulates and is deposited outside the cell. 3. The “sticky” nature of Ab-42 helps other protein fragments (including apoE) to gather into plaques. 4. These plaques and/or the migration of the Ab out of the cell causes neuronal injury and death 5. PSEN1 & PSEN2 genes subunits of g secretase. Amyloid precursor protein (APP) is membrane protein that sits in the membrane extending outward. It is though to be important for neuronal growth, survival, and repair. From: Sww.niapublications.org/pubs/unraveling/01.htm Enzymes cut the APP into fragments, the most important of which for AD is called b-amyloid (beta-amyloid) or Ab. From: www.niapublications.org/pubs/unraveling/01.htm Beta-amyloid is “sticky” so the fragments cling together along with other material outside of the cell, forming the plaques seen in the AD brain. From: www.niapublications.org/pubs/unraveling/01.htm Neuronal Plaques in Alzheimer’s Disease From http://www.rnw.nl/health/html/brain.html Tau Protein • • • • • No tau mutations in AD but some in other “tauopathies.” However, the burden of abnormal tau accumlations seems to correlate much better with dementia in AD than does the burden of amyloid or amyloid plaque accumulation Tauopathies: Diseases caused, at least partially, by abnormal forms, configurations, or accumulations of tau protein. In tauopthathies Tau is generally deposited in hyper phosphorylated form as paired helical or straight filaments. These usually form neurofibrillary tangles. Examples: AD (in part), Pick's Disease, Frontotemporal Dementia with Parkinsonism Linked to Chromosome 17 (FTDP-17), Corticobasal Degeneration, and Progressive supranuclear palsy NFT’s can also be found in dementia pugilistica, myotonic dystrophy, and prion diseases Tau Hypothesis 1. Ordinarily, the t (tau) protein is a microtubule-associated protein (MAP) that acts as a three-dimensional “railroad tie” for the microtubule, which is the conduit for axonal transport. 2. Tau phosphorylation causes tau to aggregate into proteins cause “paired helical filaments” (PHFs) leading to neurofibrillary tangles (NFTs). 3. This process impairs axonal transport causing of cell death. 4. Possibly, tau aggregates may even form “prion” like structures which promote the spread of the degeneration to adjoining neurons [This is a recent addition to the hypothesis] NFT’s Microtubules are like railroad tracks that transport nutrition and other molecules. Tauproteins act as “ties” that stabilize the structure of the microtubules. In AD, tau proteins become tangled, unstabilizing the structure of the microtubule. Loss of axonal transport results in cell death. Neurofibrillary Tangles in Alzheimer’s Disease From http://www.rnw.nl/health/html/brain.html Alzheimer’s Disease NFT’s (silver stain) SP’s (beta amyloid stain) Cortical atrophy Plaque (silver stain) Tangle (silver stain) Plaques and neurofibrillary tangles http://www.hosppract.com/genetics/9707gen.htm Senile Plaques • Spherical lesions measuring up to 100 microns • Neuritic plaques are fully developed senile plaques – Central core of extracellular amyloid – Halo of dystrophic neuronal processes with neurofibrillary degeneration – Zone around the amyloid core contains reactive astrocytes and microglia • In addition to neuritic plaques, beta amyloid can also be found in diffuse plaques and may not be associated with dementia (e.g. cerebral amyloid angiopathy) Drawings of three neuritic (senile) plaques from the brains of patients with dementia. Goedert M Brain 2009;132:1102-1111 More On Amyloid • Chromosome 21 contains the gene for the Amyloid Precursor Protein (APP) • Trisomy 21 (Down syndrome): 1.5x’s the amt of APP as typical people. But not clear that they get more AD because to the extent amyloid might “cause” AD it does so not by overproduction of APP but by defective processing which produces toxic fragments rather than normal non-toxic (and/or beneficial) fragment. Tau Protein • Tau (the Greek letter) is a microtubule associated protein, encoded by the gene MAPT gene on 17q21. Normally, tau is phosphorylated and is present mainly in axons where it binds and stabilizes microtubules. • Neurofibrillary degeneration is characterized by deposition in neuronal body and processes of INsoluble polymers of OVER-phophorylated microtubule associated protein tau. • Tau aggregates as paired helical filaments, affecting axonal transport and thus nutrition and function of the cells. • Is this the primary cause of AD? Some would say “Yes.” But it’s likely there’s a lot more to this story yet to be discovered…. Nature. 2012 May 2;485(7400):651-5. doi: 10.1038/nature11060. Prion-like behaviour and tau-dependent cytotoxicity of pyroglutamylated amyloid-β. Nussbaum JM, Schilling S, Cynis H, Silva A, Swanson E, Wangsanut T, Tayler K, Wiltgen B, Hatami A, Rönicke R, Reymann K, Hutter-Paier B, Alexandru A, Jagla W, Graubner S, Glabe CG, Demuth HU, Bloom GS. Source:Department of Biology, University of Virginia, Charlottesville, Virginia 22904, USA. AbPeptide AbPeptide Pyroglutamate Tau Perhaps the Cause is Multi-Factorial (always good to say when you don’t really know). • Protein accumulation: beta amyloid and tau, i.e. plaques & tangles •Oxidation • Inflammation: glia, microglia, cytokines, lymphokines, and whatever else is around. •Mitochondrial dysfunction • Lipid distribution: Lipid membrane site of APP cleavage. •Mutations in other genes affecting amyloid and tau •Prions and/or “prion like” proteins (perhaps altered beta amyloid or tau) •Proteasome damage •Impairment of ubiquitin system (cell wastes not cleared properly) Current gene candidates for AD: • Changes too rapidly to keep track of. • Go to http://www.alzgene.org/ for more information •Actually the above database has gotten behind. Their last update was 2011. They are working on a new version. More On Amyloid • Autosomal dominant AD develops < 65 y/o (presenile dementia) – Due to APP gene and presenillin 1 and 2 mutations (affects secretase activity) on chr 14 and 1 respectively • Apolipoprotein E (ApoE) genotype (chromosome 19) – Transports lipids in and out of cell – 3 forms (ApoE2, ApoE3, ApoE4) – Genetic risk factor as homozygous ApoE4 allele develop AD at a mean age of 70 (earlier onset) How is AD different from normal aging? Normal ADL’s Normal Memory Normal Impaired ADL’s Impaired Memory AD Normal Aging • Rate of learning may slow with age • Rate of recall may slow with age • Rate of forgetting does not increase with age Significant declines in cognitive function do not represent normal aging Vascular dementia • 2nd most common form of • Caused by degenerative • occurs when the blood supply carrying oxygen and nutrients to the brain is interrupted by a blocked or diseased vascular system • Usually occurs in “stepped” declines, whereas the decline in Alzheimer's Disease is more gradual • higher in men than in women • incidence increases with age Different types of vascular dementia • Stroke-related dementia – Single-infarct dementia – Multi-infarct dementia – Hemorrhage less common but possible • Small vessel disease-related dementia – known as sub-cortical vascular dementia – Binswanger's disease (severe form) • Vascular dementia and Alzheimer's disease ,. i.e. mixed dementia. Not uncommonly seen. Signs and Symptoms Behavioral Physical signs/symptoms signs/symptoms • • •• •• • • Memoryspeech Slurred problems; forgetfulness Language problems Dizziness Abnormal behavior Leg or arm weakness Wandering or getting lost in familiar Lack of concentration surroundings Laughingwith Moving or crying rapid, shuffling inappropriately steps • Loss Difficulty of bladder following or bowel instructions control • Problems handling money Risk factors • • • • • • • high blood pressure diabetes high cholesterol family history of heart problems disease in arteries elsewhere in the body heart rhythm abnormalities lifestyle factors (overweight/smoking) Treatment and Prevention • taking medication to treat any underlying conditions – control high blood pressure and heart disease • commitment to a healthier lifestyle – stopping smoking, taking regular exercise, healthy diet and drinking alcohol in moderation • receiving rehabilitative support – physiotherapy, occupational therapy and speech therapy • Medications for Alzheimer’s disease may also help a little DEMENTIA Causes Alzheimer's disease* Vascular dementia* Fronto-temporal dementia Parkinson's disease with dementia Lewy body dementia Progressive supranuclear palsy (PSP) Normal pressure hydrocephalus Creutzfeldt-Jacob Disease Huntington's disease Others * We will focus on the problems marked with an asterix DSM-5: Minor Neurocognitive disorder Diagnostic Criteria A. Evidence of modest cognitive decline from a previous level of performance in one or more cognitive domains (complex attention, executive function, learning and memory, language, perceptual-motor, or social cognition) based on: 1. Concern of the individual, a knowledgeable informant, or the clinician that there has been a mild decline in cognitive function; and 2. A modest impairment in cognitive performance, preferably documented by standardized neuropsychological testing or, in its absence, another quantified clinical assessment. B. The cognitive deficits do not interfere with capacity for independence in everyday activities (i.e., complex instrumental activities of daily living such as paying bills or managing medications are preserved, but greater effort, compensatory strategies, or accommodation may be required). C. The cognitive deficits do not occur exclusively in the context of a delirium. D. The cognitive deficits are not better explained by another mental disorder (e.g., major depressive disorder, schizophrenia). DSM-5: Major Neurocognitive disorder Diagnostic Criteria A. Evidence of significant cognitive decline from a previous level of performance in one or more cognitive domains (complex attention, executive function, learning and memory, language, perceptual-motor, or social cognition) based on: 1. Concern of the individual, a knowledgeable informant, or the clinician that there has been a significant decline in cognitive function; and 2. A substantial impairment in cognitive performance, preferably documented by standardized neuropsychological testing or, in its absence, another quantified clinical assessment. B. The cognitive deficits interfere with independence in everyday activities (i.e., at a minimum, requiring assistance with complex instrumental activities of daily living such as paying bills or managing medications). C. The cognitive deficits do not occur exclusively in the context of a delirium. D. The cognitive deficits are not better explained by another mental disorder (e.g., major depressive disorder, schizophrenia). Important Issues Dementia is an important public health problem that is increasing. The diagnosis of dementia is still clinical but new methods are emerging. Etiology is probably related to toxic beta amyloid fragments, neurofibrillary tangles and problems caused by other proteins. Acetylcholine is especially affected in Alzheimer’s disease and Lewey Body Disease. Current treatments are effective, but palliative. First line: acetylcholinesterase inhibitors. Alzheimer’s Disease: the Scientific Holy War The Baptists vs. The Tauists • BAPtists: The accumulation of a fragment of the beta amyloid precursor (BAP) protein or APP (the amyloid beta 42 residue fragment or Ab-42) leads to the formation of plaques that someone kill neurons. • TAUists: Abnormal phosphorylation of tau proteins makes them “sticky,” leading to the break up of microtubules. The resulting loss of axonal transport causes cell death. Neuronal Plaques in Alzheimer’s Disease From http://www.rnw.nl/health/html/brain.html Neurofibrillary Tangles in Alzheimer’s Disease From http://www.rnw.nl/health/html/brain.html