Neurodegenerative Diseases Mechanisms
60 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is a common feature of neurodegenerative disease?

  • Cellular regeneration
  • Acute inflammation
  • Chronic inflammation (correct)
  • Progenitor cell activation

    • What is the primary function of the Golgi apparatus in protein folding?

  • To receive correctly folded proteins from the ER (correct)
  • To ubiquitinate misfolded proteins
  • To facilitate protein folding into their 3D shape
  • To transport folded proteins to the ER

    • What is the result of Ca2+ overload and membrane damage in necrosis?

  • Cell shrinkage and apoptosis
  • Cell swelling and vacuolization (correct)
  • Progenitor cell activation and neurogenesis
  • Cellular regeneration and proliferation

    • What is the primary mechanism of neuronal death in chronic neurodegenerative disease?

    <p>Apoptosis</p> Signup and view all the answers

    What is the outcome of protein misfolding and ubiquitination?

    <p>Protein aggregation and neuronal damage</p> Signup and view all the answers

    What is the primary cause of ischaemic brain damage?

    <p>Acute injury</p> Signup and view all the answers

    What is the result of the systematic dismantling of a cell in apoptosis?

    <p>Macrophages removing shrunken remnants</p> Signup and view all the answers

    What is the result of raised Ca2+ levels in neurons?

    <p>Activation of protease and lipase</p> Signup and view all the answers

    What is the function of superoxide dismutase (SOD)?

    <p>To reduce oxidative stress</p> Signup and view all the answers

    What is the effect of neuronal growth factor (NGF) on apoptosis?

    <p>It decreases apoptosis</p> Signup and view all the answers

    What is the role of mitochondria in excitotoxicity?

    <p>To impair energy metabolism</p> Signup and view all the answers

    What is the result of nNOS activation?

    <p>Increased NO production with cell damage</p> Signup and view all the answers

    What is the primary consequence of excessive ROS production in neurodegenerative diseases?

    <p>Oxidative stress</p> Signup and view all the answers

    What is the primary mechanism of ischaemic brain damage?

    <p>Exocitotoxicity due to interruption of blood supply</p> Signup and view all the answers

    What is the role of SOD, catalase, antioxidants, glutathione, and vitamin E in the body?

    <p>To defend against oxidative stress</p> Signup and view all the answers

    What is the primary characteristic of the penumbra region in ischaemic brain damage?

    <p>Reversible damage</p> Signup and view all the answers

    What is the consequence of mitochondrial respiratory chain enzyme mutations?

    <p>Increased susceptibility to oxidative stress</p> Signup and view all the answers

    What is the percentage of stroke that is ischaemic?

    <p>85%</p> Signup and view all the answers

    What is the primary component of amorphous extracellular deposits in Alzheimer's disease?

    <p>Amyloid protein (Aβ)</p> Signup and view all the answers

    Which of the following is a characteristic of Down's syndrome?

    <p>Early onset of AD-like dementia</p> Signup and view all the answers

    What is the mechanism of action of Memantine in Alzheimer's disease?

    <p>Weak antagonism of NMDA receptors</p> Signup and view all the answers

    What is the effect of Tacrine on hepatic function?

    <p>Hepatotoxicity</p> Signup and view all the answers

    What is the estimated prevalence of Parkinson's disease in the UK?

    <p>1:500</p> Signup and view all the answers

    What is the primary effect of Cholinesterase inhibitors in Alzheimer's disease?

    <p>Modest improvement in memory and cognitive tests</p> Signup and view all the answers

    What is the primary mechanism of action of alteplase in treating ischaemic brain damage?

    <p>Dissolving blood clots</p> Signup and view all the answers

    Why is CT scanning required before administering alteplase in ischaemic brain damage?

    <p>To rule out haemorrhagic stroke</p> Signup and view all the answers

    What is the primary characteristic of Alzheimer's disease?

    <p>Loss of cognitive ability with no identifiable cause</p> Signup and view all the answers

    What is the region of the brain most affected in Alzheimer's disease?

    <p>Hippocampus and basal forebrain</p> Signup and view all the answers

    What is the prevalence of Alzheimer's disease at the age of 95 years?

    <p>90% or higher</p> Signup and view all the answers

    What is the proposed therapeutic approach to treat Alzheimer's disease in the future?

    <p>Administering neuroprotective agents to rescue cells</p> Signup and view all the answers

    $Ca^{2+}$ overload is a necessary factor for excitotoxicity

    <p>True</p> Signup and view all the answers

    Neuronal growth factor (NGF) and BDNF increase apoptosis

    <p>False</p> Signup and view all the answers

    Superoxide dismutase (SOD) is involved in the systematic dismantling of a cell in apoptosis

    <p>False</p> Signup and view all the answers

    Mitochondrial oxidative phosphorylation generates $NO$

    <p>False</p> Signup and view all the answers

    Excitotoxicity is characterized by the release of arachidonic acid and the decrease of glutamate reuptake

    <p>True</p> Signup and view all the answers

    NNOS activation is neuroprotective

    <p>False</p> Signup and view all the answers

    The primary mechanism of neuronal death in ischaemic brain damage is apoptosis

    <p>False</p> Signup and view all the answers

    The release of cytochrome c from damaged mitochondria always leads to apoptosis

    <p>False</p> Signup and view all the answers

    Reperfusion injury in ischaemic brain damage is caused by the release of antioxidants

    <p>False</p> Signup and view all the answers

    Mitochondrial dysfunction is a minor contributor to neurodegenerative diseases

    <p>False</p> Signup and view all the answers

    The penumbra region in ischaemic brain damage is characterized by irreversible necrosis

    <p>False</p> Signup and view all the answers

    Stroke is the leading cause of death globally

    <p>False</p> Signup and view all the answers

    Alteplase reduces mortality in ischaemic brain damage.

    <p>False</p> Signup and view all the answers

    CT scanning is required before administering alteplase to diagnose ischaemic brain damage.

    <p>True</p> Signup and view all the answers

    The prevalence of Alzheimer's disease is 5% at 65 years and 90%+ at 95 years.

    <p>True</p> Signup and view all the answers

    Surgery is the primary means of treating ischaemic brain damage.

    <p>False</p> Signup and view all the answers

    Neuroprotective agents are currently used to rescue cells in the penumbral region of ischaemic brain damage.

    <p>False</p> Signup and view all the answers

    Atherosclerosis is the primary cause of Alzheimer's disease.

    <p>False</p> Signup and view all the answers

    Neurodegenerative diseases are characterized by a single pathological process causing neuronal damage or death.

    <p>False</p> Signup and view all the answers

    Ischaemic brain damage is a chronic condition.

    <p>False</p> Signup and view all the answers

    Normal protein folding occurs in the Golgi apparatus.

    <p>False</p> Signup and view all the answers

    Apoptosis is a mechanism of neuronal death involving cell swelling and membrane damage.

    <p>False</p> Signup and view all the answers

    Oxidative stress is a primary mechanism of neuronal death in acute neurodegenerative disease.

    <p>False</p> Signup and view all the answers

    Neurogenesis is the process of neuronal death in neurodegenerative diseases.

    <p>False</p> Signup and view all the answers

    All forms of Alzheimer's disease are caused by mutations of the APP gene.

    <p>False</p> Signup and view all the answers

    Amyloid plaques are composed of phosphorylated Tau protein.

    <p>False</p> Signup and view all the answers

    Tacrine is effective in treating Alzheimer's disease in all patients.

    <p>False</p> Signup and view all the answers

    Down's syndrome often leads to late-onset Alzheimer's disease.

    <p>False</p> Signup and view all the answers

    Memantine is a strong antagonist of NMDA receptors.

    <p>False</p> Signup and view all the answers

    Parkinson's disease only affects movement control.

    <p>False</p> Signup and view all the answers

    Study Notes

    Mechanisms of Neuronal Death

    • Apoptosis: programmed cell death, essential mechanism, systematic dismantling of cell, activation of caspases, shrunken remnants removed by macrophages, no inflammatory response
    • Neuronal growth factor (NGF) and BDNF: ↓apoptosis, ↓Bax (pro-apoptotic) and ↑Bcl-2 (anti-apoptotic)

    Excitotoxicity

    • Glutamate (Glu): highly toxic to neurons, Ca2+ overload is an essential factor
    • Raised [Ca2+]: ↑Glu release, ↑protease and lipase activation, activation of nNOS
    • ↓[NO]: neuroprotective, ↑[NO] + ROS = cell damage
    • ↑arachidonic acid release: ↑ROS and ↓Glu reuptake

    Oxidative Stress

    • Mitochondrial oxidative phosphorylation: generates ATP
    • Mitochondrial energy metabolism: impaired mitochondria, Parkinson's, Stroke
    • Superoxide dismutase (SOD): defence against oxidative stress

    Neurodegenerative Diseases

    • Pathological process(es) causing neuronal damage/death
    • Neurogenesis: formation of neurons from progenitor cells
    • Ischaemic brain damage (stroke): acute
    • Alzheimer's disease: chronic
    • Parkinson's disease: chronic

    Protein Misfolding and Aggregation

    • Proteins folded to their 3D shape in ER
    • √ folded proteins → golgi
    • X folded proteins → ubiquinated
    • Protein misfolding and aggregation: essential mechanism in neurodegenerative diseases

    Ischaemic Brain Damage

    • Necrosis: due to acute injury, cell swells, Ca2+ overload, membrane damage, cell swelling, vacuolisation, and lysis
    • Spills contents of cell into surrounding tissue: inflammatory response
    • Chronic inflammation: feature of neurodegenerative disease
    • Alteplase: plasminogen activator, disperses thrombus, reduces mortality, but significant functional benefit

    Alzheimer's Disease

    • Loss of cognitive ability with age: normal
    • AD: dementia that does not have a cause
    • Prevalence rises with age: 5% at 65yrs to 90%+ at 95yrs
    • Age-related dementia: accelerated neuronal loss, falling blood supply due to atherosclerosis
    • Associated with brain shrinkage and localised loss of neurons: hippocampus and basal forebrain
    • Loss of cholinergic neurons: hippocampus and frontal cortex

    Pathogenesis of Alzheimer's Disease

    • Excessive ROS production: oxidative stress, NO synthesis, arachidonic acid metabolism
    • Reperfusion: leukocytes release cytotoxic oxygen, damages DNA, enzymes, and membrane lipids

    Oxidative Stress and Defence Mechanisms

    • Defence mechanisms: SOD, catalase, antioxidants, glutathione, and vitamin E
    • Oxidative stress: cause and consequence of inflammation
    • Mitochondrial integrity: essential for neuronal survival
    • Mitochondrial respiratory chain enzyme mutations: congenital or age-related, ↑in susceptibility to oxidative stress
    • Damaged mitochondria: cytochrome c release, pro-apoptotic

    Ischaemic Brain Damage

    • Stroke: 2nd most common cause of death globally (WHO, 2015)
    • 70% of stroke: non-fatal
    • 85% of stroke: ischaemic
    • Thrombosis/blockage of artery
    • 15% haemorrhagic: rupture of a cerebral artery
    • Interruption to blood supply: exocitotoxicity
    • Central core: irreversible necrosis
    • Reperfusion: production of ROS on restoration of O2
    • Takes hrs to develop: therapeutic opportunity
    • Penumbra surrounds core: inflammation and cell death

    Therapeutics

    • No drugs to halt AD
    • Cholinesterase inhibitors: tacrine, modest improvement in memory and cognitive tests
    • Memantine: weak antagonist of NMDA, potential inhibitor of excitotoxicity
    • Modest cognitive improvement, not neuroprotective

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Neurodegenerative Diseases 20-21 PDF

    Description

    Test your knowledge of neurodegenerative diseases, including mechanisms of neuronal death, protein misfolding, and aggregation. Learn about Alzheimer's and Parkinson's diseases, as well as ischaemic brain damage. Understand the pathological processes causing neuronal damage and death.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser