IOC World Congress on Sport Science (2003, Oct, Athens)


IOC World Congress on Sport Science, Oct, 2003 Genes and Performance Wednesday, 1030am, Chair: Bengt Saltin

Genes and Health Greg collier, AGT Biosciences, LTD, Deakin Uni, International Diabetes Institute and South West foundation Texas

PARL a  new gene involved in muscle function and type 2 diabetes

Literature is full of candidate gene studies – not worth the paper their written on

Unique DNA collection

AGT Biosceince cetre for Stat Genomics

Outbread Israeli Sand Rat Colony

Ezpress Technology Platform

AGT Biosceinces has access to number of human DNA sample collections

Access to unique DNA collections from worldwide populations

Major Collaborators

Dr. John Blangero, Texas -    analysis of genetics of many complex diseases -    devel opf new stat software -    SOLAR

Native habitat is semi-arid regions of middle east

Israeli sand Rat develops diabetes and obesity in manner similar to humans

PARL – Preseneilins-associated rhomboid-like protein

7 transmembrane protein

predicted was located in mitochondria – regulating basic muscle function

Located at chromosome 3q27

Reduced gene expression in muscle of diabetic P. obesus

PARL gene expression was increased after exercise-training

Human gene expression data -    Eric Ravussin, Anthony Civitarese (Pennington Biomedical Research Center)

Discovered by microarrary….

REF: McQuibban, Nature 423, 534 (2003) -    in mitochondria, yeast equivalent…. -    if knock gene out, mitochondria shrink and don’t function correctly

PARL cleaves human equivalent of OPA1… -    in diabetic muscle, where decreased expression of PARL, this is a problem

Mitochondrial defects in genes occur before diabetes occurs

Dgene expression I skeletial musc asso with

REF: Kissebah, AH PNAS 97, 14478 (2000)

Genotyping 50 individuals, XXX

Association studies

Look at relationship of XXX

Responsible for about 5% of variation in insulin levels

Largest yet genetic variation causing insulin resistance

Discovered in muscle of animals

Leu26Val variant of parl asso with plasma insuli, with a strong genotype-by-age variant

Finding genes like this is not simple

Need to combine human linkage studies with expression

Not a worthwhile task to identify a gene and find an association

Brain health, and voluntary running Frank Booth

Epidemiological reports indicate that physically active elderly humans have less cognitive dystnfunction

Laurin Arch Neurol. 58:498, 2001 -    women 65 yars or older, evaluated -    highlevel of phys activ corresponsed to exercise

What is the mechanism? How phys activ tie into brain disfunction

Brain derived neuro..factor (BDNF)

Lu Learn, Mem. 2003, 10: 83-85

Wifdenfalk Neurosci Res 34 125: 1999 -    animals running more had increase in XXX (i.e.

Located in hippocampus -    Hippocampus is highly plastic structure normally asso with cog function, rather than motor

Malcangio Trends Pharmacol Sci 24:116, 2003-10-08

Increase in neurogenesis in hippocampus in animals that are running, compared to animals who are not running

Running primes t brain to enhance neuronal health

It is dogma in medicine that health indivs are the control group and t sick patients are treatment group

It is dogma in exercise that healthy indivs are t treatment group and t sicker population is t control group

Nby calling t phyaically active group t treatment, some others outside of exercise believe that being sedentary is health and thus see no reason to further supp exercise research

Carro, J. Neurosci. 21, 5678, 2001 Carro Mol Neurobi9ol 27, 153, 2003-10-08 -    Increased sendetarism, contributes to an increasing incidence of neurological diseases -    Sedentary life is a risk factor for neurodegenerative disease

What genese are changing in brain that will protect you from neural degeneration

(Saltin: Have identified candidate genes, now how activate?)

Kinetic Consideration of endurance training adaptations Name?

Approx 4 weeks before protein increase, through training

In 1980s, mRNA increase detected after 2 weeks

How do muscle cells adapt to exercise?

Metabolic genes: at transcription or mRNA (transient response)

Measure mRNA increases (transient) 48hrs after exercise – inc in protein concentration

Stress genes Priority Genes Metabolic/Mitochondrial Genes

Adaptations from training have to stem from acute stimulus (exercise bout)

Trying to indicate different categories of genes

Example: PDK4

protoocal after 4 weeks of one-legged knee extensor exercise train

24 hrs after exercise bout, mRNA back to basel levels

during exercise, why would muscle want to shut of a gene that produces carbohydrates? -    hyp: as glucose ….muscle no longer want to use…

Endurance (PGC-1) David Hood, York University, Toronto

Endurance = high capacity of mitochondrial enzyme activity Not only applicable to endurane athletes, but also sedentary individuals – no exercise, low mitochondrial content and endurance capacity)

Ageing and low physical activity, bring mitochon down

Changes in energy status and calcium,. XXXX l

Leads to change of nucleus – transcription factors

Stimuli that affect transcription of nuclear genes

Mitochondria has its own genome -    very limited, only codes for 13 genes (and 100s of genes reqd for mitochondrial function) -    transcription factor for 13 genes is TFAM

Studied with animal model -    chronic stimulation

typical marker for mitochondria (cytochrome C) -    Freyseeenet, et al AJP 277, E26, 1999

Performance change -    muscle force greater fatigue resistance (40% improvement)

PGC-1alpha -    popular due to widespread effects in cell biology -    mediates thyroid -    influ on muscle fibre type -    affects mitochondrial biogenesis

co-activator not a transcrioption factor not binding DNA, but binding transcritpopn factors -    e.g. NRF-1, thyroid receptors (can enhance)

with chronic stim model, looked at PGC-1 level -    nothing happened after 3 days, but by 5, 7, 10, increase in PGC-1 protein by 50% (Irrcher et al AJP 2003, 284)

used cells for better control induce to fuse together -    immature muscle cell. Can make contract, or treat with drug -    not physiological, but useful -    is calcium important in mitochondrial biogenesis

number of transcriptors that could be involved in calcium response -    2.5x inc in PGC-1

effects of exercise on PGC-1 might be mediated by calcium

stimulation model -    cells stimulated in disk -    compared to non stimulated -    looked at factors o    PGC-1 coactives NRF-1 o    NRF-1 transcriptionally activates Tfam and Cyto c) o    Tfam imported to mito and inc mtDNA transcption and copy number o    P38 MAP kinases phosphorylation stablizes PGC-1 protein o    Irrcher et al AJP… (as abobe)

Effect of altering AMPKalpha activity with AICAR -    inc in PGC-1 levels -    which will ultimately affect mito levels

if understand PGC-1, can understand what affects mitochondrial levels

thyroid hormone is another potent stimulator of metabolism -    high thyroid, high mito -    hypo-thyroid is opposite -    also acts by PGC-1

Conclusion

Contractilve activity-endurance signalling of mito bigenesis involves both calcium signals and changed I  ATP turnove and is mediated by PGC-1alpha

Important role of PGC-1 in mataining normal levels…

How neuronal activity controls muscle fiber type and fiber size S. Schiuaffino, Padova

Dissecting signalling pathways involved in activity-dependant muscle gene regulation

Fiber types in skeletal muscle Genetics important, but other factors can modulate fibers -    motorneuron activity is major factor

motorneuron modulate fibre size and fibre type

mechanical effects also important, and one of less explored areas -    sports that generate tension in muiscle (e.g. weightlifting) can induce muscle hypertrophy metabolic changes -    exercise can inc AMP and can activate…?

Try to identify important transaction pathways (activate and block) -    How? o    Pharma not helpful o    Need a genetic approach •    Somatic transgenesis •    Transgenic mice: long procedure •    Instead make transgenic muscles o    Inject foreign DNA through plasmid o    In few days, see effect in muscle phenotype e.g. Changes in MyHC gene expression inducaed by slow motor neuron…

injected mutant  transducers to see if can block effect of nerve or to induce denervated muscle

Murgia et alNature Cell Biol, 2000 Serrano el al PNAS 2001 Pallafaccihna et al PNAS ,2002

Effects: two fibres (injected with foreign DNA) do not express slow myocin

More recently identify transcription factor -    NFAT (transcip factor, protein binding DNA o    Known to translocate o    This translocation been able to….directly, linkd to GFP (fluorescent protein)

Same approach can be used to study muscle hypertrophy

(Saltin: people are on path to find out how performance is regulated)

An overwall enlargement of skeletal muscles is obtained by training and enhanced by anabolic steroids Name? (Female, Paris)

What’s important in skeletal muscle is, as muscle grows, inc proteins, mitochondria, and myonuclei and satellite cells are controlling this

What happens to nuclei in muscle that accompanies growth of muscle fibre As indiv trains (power train), is inc in myonuclear number, and anabolic steroids increase myonuclear number -    amount of cytoplasm remains constant

if inc in no. of nuclei, means that cells have to be added in and must come from myonuclear component

skeletal muscle has cell, reserve cell

satellite cells can proliferate, to allow muscle to grow -    also used to repair muscle

sat cells can be isolated from muscle and grow from biopsy

sat cells isol from human muscle fibres, have ltd capacity to cell

from birth can make 60-70 divisions -    most of these lost during rapid growth

then, muscles stop growing -    from 20-90yrs, maintain capacity to grow and repair skel muscle

Mitotic Clock -    this is why there is a limited capacity, limited by Telemere (on each chromosome, is a piece of redundant DNA, each time cell divides, small part of this DNA will be lost, after while, signals to stop cells from further division, protects cells from cancer, but limits no. times can divide)

in athletes, no. of satellite cells increase on muscle fibre -    to inc muscle mass, to repair muscle

same biopsies – look at telemere length, compared to sedentary -    in elite pro athletes, is small decrease in Tele DNA, muscle is turning over much more than in sedentary population

Athletes with FAMS (Fatigued Athlete Myopathic Syndrome  - Noakes) -    suffering from chronic fatigue -    connective tissue abundant -    inc internal nuclei -    abnormal mito nuclei

compared with control group of sports people

in this syndrome, where overtrain and genetic background, where cannot replenish sat cells, is pathologic – comparable to genetic disease

similar decrease in sat cells in weightlifters with large doping history

lose telemetric DNA each time cell divides

in cell culture, when isolated from elite athletes, compared to sedentary, doing small amount of regular activity is beneficial, because amateurXXXXX? -    what level of activity is beneficial, compared to excessive exercise

Muscle satellite cells activation and skeletal muscle mass recognition Geoff Goldspink

Muscle mass muss be regulated locally and systemically -    must be local growth factors

Alterantive Splicing of Human IGF-1 gene -    now call mechano growth factor (only detected in ?) o    derived from IGF-1 •    IGF-1 genereal growth factor that makes cells inc in size

Normally think of IGF-1 as produced in liver

But MGF has different sequence and different action to systemic factor Activated by chemical signals quickly after exercise?

49 base insert -    ie.  Downstream shifts

put cDNA into different plasmids using same techniqe as earlier paper (inject to muscle of mouse)

made some constructs for in vitro when pt into mouse, found that a group of fibres that hve been tranZZ have inc in size within 2 weeks (25% larger) -    potent growth factor)

how was it doing this? -    looked at cells in culture -    put interest into C2C12 cells o    saw effects of systemic IGF-1, increased in mass, but …?

Subjected rat to mechanical damage, put in myotoxin agent -    to see repair, etc

if look at marker for sat cell activation -    sat cells inc in numbers quickly after injury -    what sort is activating? o    Discovered that shortly after injury MGF is expressed •    Chief contender as major factor activiating sat cells Need to replenish pool of cells, but not too much

Muscles respond to mechanical signals – how? -    not enough sat cells -    seems that they are not activated -    all muscles do not respond to exercise as well, since do not prod enough MGF

(Saltin: now health subject)

Muscle Contraction Febbraio?, Female, Brown hair

Plasma IL-6 -    Ostrowksi et al J. Physiol 1998 -    Ostrowski,

Is IL-6 produced during exercise? -    yes, by working muscles, when it is released into circulation

role of muscle glycogen? -    systemic vs. local effects -    transcription rate inc with exercise, but further enhanced when muscle glycogen is XXX?

What does it mean to feed athletes carbohydrates during exercise? -    IL-6 is inhibited

Febbraio et al 2003

If IL-6 was being produced to signal to liver to produce glucose? -    not clear from findings

Febbraio hiscock, fischer, sachetti, Pederson -    2hrs cycling, at 40% VO2max….etc -    IL-6 can influence glucose production, but co-factor is required

Does IL-6 induce lipolysis? -    yes. Van hall, et al J clin endorcinol metab june 2003-10-08

Keller, FASEB, J, December, XXXX?

Nutrition – supplementation and sports performance

Ergogenic aids:food for performance or food for thought

Diet, training and ergogenic aids: t evidence from antiquity Louis Grivetti

Examples of

Doping Substances in Nutritional Supplements: Results of an IOC study Hans Geyer

Since 1996, Prohormones available over counter

Prohormones of Testosterone -    DHEA

Prohormones of Nandrolone

Labelling of preparations does not reflect actual content

Parasrampuria M. et al 1998

Insufficient urveyence of prohormones

Now analyse  non hormonal

Broad based study of international market

634 nutritional supplements purchased from Oct2000 – Nov 2001

in 13 countries

mainlybourght in shops (91.2%) and internet

289 supplements (49%) from prohorone selling companies

Results: 15% of nutritional supp,ements contained anaboligc androgenic not on label

most of positive nutritional included DHEA andendion

most positive products came from US companies (about 90%!)

do only prohormone companies have positive samples?

10% of products from non pro-hormone also positive

does application of such contamination of substances, lead to positive doping results -    Yes, especially if prohormone of nandrolone

Many victims of contaminated substance? -    Christie, ottie, etc

Conclusion

Problem of non-hormonal nutritional supplements containing prohibited anabolic-androgeneic is international problem

Consumption can lead to positive doping

Minimize risk, athletes should only buy nutritional supplements from companies which perform qualiy check for prohormones that guaranteee

In germany have companies that

www.osp-koeln.de -    low risk suppplments (cannot excp

www.dopinginfo.de

in this study, cases were too low to have a physiological  affect

example from Belgium where athlete has managed to gain compensation from

Muscle Glycogen: train low – compete high

Carbo ingestionduring exercise of longdurationin c performance

High muscle glycogen enhances time to exhaustion

What are infol of CHO ingestion and uiscle glycogen on training??

Training adaptation: what is influ of training at low versus high XXX

Training adaptation -    what is that? -    Molecular mechanisms? o    Accumulation of proteins o    How accumulate protein in muscle?

Prof. Choulis,

Framing it as a problem.

Number of durugs see

Questions

Randy Welberg, USOC presentations

Goldspink - china, factor 8 - haemophilia