Transcript Monster Cow & Steroid Slides

Monster Cows: Belgian Blue Cattle,
80% meat
• Originated in the early 1900’s Farmer’s selectively bred
for the “double muscled” appearance, and from the
1960’s on genetic selection techniques enhanced the
trait. A carcass can be up to 80% meat. They are so
muscled they often cannont give birth without C-Section.
What trait? Do they have crazy exercise? Well that
helps with the tone, however they have a defective
myostatin gene. They’re growth supressor is inhibited.
So nothing keeps them from growing. What kinds of
disease could we use this genetic mutation to treat?
Dissections comparing normal,
heterozygous, and homozygous
mice
Myostatin
• A growth factor
(hormone) that
surpresses muscle
growth.
– Slows down development
of muscle stem cells
• In 2002, researchers at
the University of
Pennsylvania showed
that monoclonal antibody
specific to myostatin
improves the condition of
mice with muscular
dystrophy, presumably by
blocking myostatin's
action.
The number of fibers is probably fixed early
in life. This is regulated by myostatin, a
cytokine that is synthesized in muscle cells
(and circulates as a hormone later in life).
Myostatin suppresses skeletal muscle
development. Cattle and mice with
inactivating mutations in their myostatin
genes develop much larger muscles. Some
athletes and other remarkably strong
people have been found to carry one
mutant myostatin gene. These discoveries
have already led to the growth of an illicit
market in drugs supposedly able to
suppress myostatin. However these are
only fake drugs so far.
In adults, increased strength and muscle
mass comes about through an increase in
the thickness of the individual fibers and
increase in the amount of connective
tissue. In the mouse, at least, fibers
increase in size by attracting more
myoblasts to fuse with them.
Carl Lewis
• Ran 100 m in 9.86s
– 1991 world record
– Jumps over cars
– 9 Gold Medals
• Excellent example of
Type II fast twitch
muscle
• Also a vegan
• Outspoken, even
damning of those who
used performance
enhancers.
– Like Ben Johnson
Ben Johnson
• Between 1968 and
1983 the 100m record
was shaved by 0.04s
• In one year Johnson
beat it by 0.16s
• 1988 Seoul Olympics
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Johnson: 9.76 s
27 mph
45 strides
Ahead the whole time
Lewis sets an
American record with
9.92s, but still second
• Busted for doping
Back to Carl Lewis
• Johnson’s medal revoked
and given to Lewis
• 5 years later in 2003
Lewis admits he was
busted 3 times in 1988 for
banned stimulants.
– He “thought they were
herbal supplements”
– The U.S. Olympic
committee found his
ingestion to be,
“inadvertant”
– Since it was after the 3
year statute of limitations
he could keep his medals
– Stimulants could have
• Johnson beating Lewis in
‘88
Which leads to the question how do steroids
work?
• Androgenic: increasing
masculine traits
• Anabolic: building muscles
as opposed to
• Catabolic: breaking down
nutrients
Jason Giambi
Barry Bonds
Sammy Sosa
Mark McGwire