Queensland Brain Institute

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Queensland Brain Institute
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Outline

• Background
• Technology
• Overview of stem cell research
• Motor neuron disease

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Background

• Established in 2003 within The University of
  Queensland
• Founding Director Professor Perry Bartlett, FAA
• QBI has become one of the largest basic
  neuroscience research institutes in the world

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Vision

• To discover the mechanisms regulating brain
  function and translate these findings into new
  therapeutics to promote and restore optimal,
  lifelong neurological and mental health for the
  people of Queensland and Australia.

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The Problem
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Technology

• Advanced imaging
• MRI, microscopy
• Animal research facility
• Surgery, behaviour, drug trials
• Cell sorting
• e.g. for isolating stem cells
• Gene profiling
• Human genome on a chip
• Computational neuroscience
• World class computer capabilities

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Advanced imaging technology

• Magnetic Resonance Imaging (MRI) 16.4T wide-bore
  spectrometer

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In vivo DTI of mouse spinal cord
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Human genome on a chip
We are using these chips to look for differences
between healthy people and people with MND. We
aim to identify a diagnostic fingerprint for MND.
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New Facilities

• QLD gov
• Smart State
• UQ
• Atlantic
• Philanthropies

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Leading science journals
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Collaborations

• Institute of Neuroscience, Shanghai
• Riken Brain Institute, Japan
• Trinity College Institute of Neuroscience,Dublin
• McKnight Brain Institute, USA

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Main areas of research

• Neural plasticity
• Cognitive and behavioural neuroscience
• Ageing and brain disorders
• Visual neuroscience

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Visual neuroscience

• Seeks to elucidate principles of flight control
  and navigation, and to explore the limits of the
  cognitive capacities of small brains such as
  insects

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The brain is plastic!

• The adult brain is not hard-wired and can rapidly
  change both
• repertoire and strength of synaptic connections
  on existing nerve cells
• Basis of learning and memory
• repertoire of nerve cells themselves
• neurogenesis

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Neurogenesis

• Until a decade ago, it was generally accepted
  that the generation of new nerve cells in the
  central nervous system did not persist into
  adulthood.
• It is now clear that stem cells exists within the
  adult brain, and these cells continue to divide
  throughout life.
• These cells are capable of migrating and
  generating new neurons and glia which integrate
  into the existing functional circuitry.

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Neurogenesis
Self renew, long-lived Difficult to distinguish
from a stem cell All brain cell types are
formed from a single cell
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Neurogenesis
Disorders in which nerve cells are lost
Neurodegenerative disorders such as Alzheimers
and Parkinsons. Trauma such as stroke and spinal
cord injury. Other diseases such as epilepsy and
MND. Depression and other mood disorders.
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Unique Focus

• The mechanisms controlling neurogenesis will have
  broad application in treating neurological and
  mental illnesses, and promoting optimal brain
  function in an ageing population

Goal

• Find the key molecules regulating neurogenesis.
• Test in animal models of disease, behaviour and
  ageing.

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Disease targets of new therapeutics

• Huntingtons
• Spinal cord injury
• Brain tumours (gliomas)
• MND

• Ageing/Dementia
• Stroke/Rehabilitation
• MS
• Parkinsons
• Epilepsy
• Psychiatric Disorders

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How can we increase neurogenesis

• Learning
• Exercise
• Diet
• Growth factors
• Small peptides
• Prozac

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Using Prozac to treat Huntington disease

• Progressive neurodegenerative disorder affecting
  the cortex and striatum
• Motor, cognitive and psychiatric symptoms
• Mice with HD were given Prozac in their drinking
  water, then tested for improved cognitive function

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Effect of Prozac on spatial memory in HD mice
Spontaneous alternation in the T-maze
Trial 1 Forced to go left
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Effect of Prozac on spatial memory in HD mice
Spontaneous alternation in the T-maze
Trial 2 Allowed to choose
Normal mice prefer to explore the new arm 70 of
the time.
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Spinal Cord Repair

• QBI researchers, in collaboration with
  researchers from the University of Melbourne and
  elsewhere with UQ, are working together to
  develop a therapeutic to stimulate the repair of
  newly damaged spinal cord.

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Lesion site
Caudal
Rostral
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Brain Tumour Research

• QBI neuroscientists are working on a new approach
  to treating aggressive brain tumours, using a
  protein that has already been shown to
  dramatically inhibit brain cancer stem cells in
  laboratory animals.

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Translational Research Institute (TRI)

• Building expected to begin in 2008
• Major medical research base to produce and test
  new drugs and vaccines
• To be located at the Princess Alexandra Hospital,
  Brisbane
• Initiative of Prof. Ian Frazer (Gardasil,
  cervical cancer vaccine)
• An Australian first and one of only a handful in
  the world

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Genetics of Motor Neuron Disease
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90

• sporadic MND
• Most people with MND are the only known person in
  their family with the disorder.
• familial MND
• MND is sometimes inherited, with more than one
  affected person in a family.

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90

• sporadic MND
• Most people with MND are the only known person in
  their family with the disorder.
• familial MND
• MND is sometimes inherited, with more than one
  affected person in a family.

Mutations in SOD1 account for 20 of familial MND
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• sporadic MND
• Most people with MND are the only known person in
  their family with the disorder.
• familial MND
• MND is sometimes inherited, with more than one
  affected person in a family.

Mutations in SOD1 also account for 1-4 of
sporadic MND
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• sporadic MND
• Most people with MND are the only known person in
  their family with the disorder.
• familial MND
• MND is sometimes inherited, with more than one
  affected person in a family.

This area (8) represents unknown MND genes
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• sporadic MND
• Most people with MND are the only known person in
  their family with the disorder.
• familial MND
• MND is sometimes inherited, with more than one
  affected person in a family.

Genes environment
This area (8) represents unknown MND genes
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Current research aims

• Identify new genes which cause familial MND
• Collaborating with hospitals in China
• Using mice
• Understand how MND is caused by faults in SOD1
  and other genes
• May be relevant to sporadic MND
• Discover ways of preventing and treating MND.

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Familial MND
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Gene identification is difficult

• Need large families for mapping genes
• Late onset, often rapid course
• Makes DNA collection difficult
• Can take many years to collect
• Small families can be analysed together
• Different families may have different genes
• Needs very large numbers

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Using mice to find MND genes

• Laboratory mice also get MND (eg SOD1 mice)
• ANU have a large collection of mice that carry
  different unknown gene mutations (caused by
  injection of a chemical)
• We are currently screening these mice for
  MND-like symptoms

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Strategy
Screened using a grip strength meter
100s of mice with different gene mutations
Gene mapping
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Mice with MND-like features

• 5 mice with movement defects have been identified
• We are now looking for motor neuron loss in their
  spinal cords (too time consuming to use as a
  screen)

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How will finding MND genes help?

• Diagnosis
• Understanding
• Treatment
• SOD1 as an example

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SOD1 diagnosis

• For the test, a blood sample is taken and sent to
  a laboratory where the DNA is isolated and SOD1
  is tested
• No testing should be carried out without advice
  from a genetic counsellor

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Implications

• If an SOD1 mutation were identified, it would
  have significance for other family members.
• If an individual has a mutation in SOD1, each of
  their children has a 50/50 chance of inheriting
  the faulty gene.
• Important if it becomes possible to prevent MND

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Understanding MND in SOD1 mice
SOD1

• SOD1 aggregates
• Cell-cell interactions
• Free radicals
• Mitochondrial dysfunction
• Overproduction of glutamate
• Activation of cell death pathways

Bendotti Carri, 2004
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Testing novel therapies

• Peptides designed to target specific receptors
• p75
• EphA4

• Gene therapy
• But what gene do we introduce?

• Cell transplants
• Can healthy astrocytes rescue sick neurons?

• Stem cells
• Not yet successful in humans

SOD1 mice
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Testing p75 peptides in SOD1 mice

• p75 is a molecule that appears in motor neurons
  that are dying
• QBI have developed peptides that block p75 and
  prevent motor neurons dying in cell culture
• We are now testing the SOD1 mice
• Mice received bi-weekly injections and their limb
  weakness and co-ordination tested over several
  weeks

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Rotarod test

• Mice with motor neuron disease are unable to
  balance on a rotating rod

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Rotarod performance
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Rotarod performance following treatment
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Preliminary results

• P75 treatment is promising and may be more
  beneficial if administered from an earlier age
• Once a preventative treatment is available,
  predictive testing for SOD1 will become important.

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Conclusions

• Understanding the genetics of MND will.
• Lead to improved diagnosis
• Improve our understanding of what causes motor
  neuron loss in patients with MND
• Help us to develop treatments for MND

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www.qbi.uq.edu.au
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http//www.abbc.edu.au
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The Genetics of Human Epilepsy

• Robyn Wallace
• Queensland Brain Institute

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Epilepsy can be inherited

• 400BC On The Sacred Disease
• Hippocrates suggested that epilepsy was a disease
  of the brain.
• First to note that epilepsy is familial

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Twin Studies (Berkovic, 1998)
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Causes of Epilepsy
others
tumour
trauma
stroke
unknown
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Generalized Epilepsy with Febrile Seizures Plus
(GEFS)

• Mixed seizure types
• Febrile seizures
• Febrile seizures beyond 6 yrs (FS)
• Generalized epilepsy absences, tonic-clonic
  seizures

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GEFS Pedigree

Febrile seizures
Generalised epilepsy

Febrile seizures plus
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TCCTGGAGCTAGCTGGTTTTACAATTTAATGGTGAAAATGACTGCCACCT
TAAACTTCTA ACTTAGCTGGAATTCTCATTCTACCACCTAGATGCTTGG
GTTCCTCCAGCAAGGGACTTT CTGAGGAAGGGGCACTCGGGTAGCATAA
AGTCTGAGTTACCGGCAACGTTGACAGTCCCA
CTTATGGGGCCTCCCATGTACAAGGCCCTACCTAATGTATGAAAATGGGC
CCAGCCATTG CTGGAAGCAAAGGACCATTTCTTTCAACAAGAGAGAGGG
AAACTGAGACTCAGGGATGAA TGACTTGCTGAGGTCACGCAGTGAGTGA
CAGGGCTCAGCCTAGCATCCAGTCCTGTCTGC
TGGTAATCATTGAGGGGGGAACAGATGGTTTGTGAGGGGTCTGGCATTGC
TTAGGGCAAT GGGTGCCTCTGCCTGACCTGAGCCTGCTGTCCCCACAGT
GTCCTCAGCCTGCGGGGGCTG CGTGGAGGTGGACTCGGAGACCGAGGCC
GTGTATGGGATGACCTTCAAAATTCTTTGCAT
?
6,000,000,000 lt20,000
base pairs base pairs
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Identifying the GEFS gene

• localised the gene to chromosome 19
• searched databases for a gene on this chromosome
• sodium channel ?1 subunit (SCN1B)

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Voltage-gated Sodium Channel

• Membrane protein comprised of one ? and two ?
  subunits
• Essential for normal nerve cell activity (action
  potentials)
• Some antiepileptic drugs target sodium channels
  (eg phenytoin)

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C121W Mutation
DNA GGC GAC TAC GAG TGC CAC GTC TAC
CGC sequence G Amino
Gly Asp Tyr Glu Cys His Val Tyr
Arg Acid sequence Trp
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sodium channel ? subunit
C121W
?
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Functional Analysis

• to determine the effect of the gene alteration on
  sodium channel function
• the human sodium channel was expressed in Xenopus
  oocytes
• the ? subunit requires an ? subunit to form a
  functional channel

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current
voltage
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? subunit - Functional Analysis
closed
??????
? C121Wb
?
time
open
(msec)
Channel remains open longer than
usual Hyperexcitability of cells seizures
Courtesy AL George
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Frequency of GEFS Mutations

• 50 unrelated GEFS cases tested
• Na ? subunit - 3/50
• Na ? subunit - 5/50
• GABA receptor - 2/50
• account for 20 of GEFS cases

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Overview of epilepsy genes

• Sodium channels
• Propagate electrical signal within a cell

• GABA receptors
• Chemical signal between cells

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Outcomes

• Genetic testing now available
• Sodium channel mutations
• Important for medication
• Drug discovery underway
• Cells with mutated sodium channels are currently
  being used to identify novel drugs for epilepsy.
• A mouse carrying the GABA receptor mutation is
  being used to test potential drugs

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Human Epilepsy Genes
GENE
FUNCTION
FUNCTION
GENE
SCN1A
LGI1
Sodium channel
Potassium channel-associated
SCN2A
EFHC1
Sodium channel
Calcium channel-associated
SCN1B
CHRNA4
Acetylcholine receptor
Sodium channel
CHRNB2
Chloride channel
Acetylcholine receptor
CLCN2
GABRG2
GABA receptor
Potassium channel
KCNQ2
GABRA1
Potassium channel
GABA receptor
KCNQ3
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Human Epilepsy Genes

• 12 genes discovered to date
• Account for only a small proportion of epilepsy
  patients
• Many epilepsy genes yet to be discovered

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Future

• Predictive testing
• Improved antiepileptic drugs
• Novel therapies
• Stem cell therapy
• Gene therapy
• A cure for epilepsy