0:00
Hello,
my name is Hiroyuki Saturai,
professor of pharacology, Kyorin
University School of Medicine,
Tokyo, Japan.
Today, I'd like to discuss
urate transport in our body.
I will try hard to explain
physiological principles
of urate transport so that my talk
is applicable not only to urate,
but also to many negatively
charged xenobiotics
or endogenous substrate.
0:29
So this is the agenda for this talk.
I will briefly discuss about
what urate is doing in our body.
Then we move to the physiology
of trans-epithelial movement
of the solute.
Then I will come back
to urate handling
and especially in the two key
organs in urate metabolism,
kidney and the intestine.
Then I will finish with drugs
that affect urate transport,
either a treatment or a side effect.
1:02
This is the yin and yang of
urate, so good and bad of urate.
If your uric acid is
very high, many doctors
think that you are in trouble
such as gout, or arthritis, kidney
stones.
However, urate itself
is a major antioxidant.
This is a bright side.
Some people say that once humans
could retain urate in their body,
vitamin C, also known as a
very strong anti-oxidant,
we lost an anti-oxidant possibly
at that time when we got urate.
But superoxide is generated
through urate production
by xanthine oxidase.
And this free radical, superoxide,
causes lots of trouble.
It appears that radical damage and
the anti-oxidant effect of urate
canceled out.
But other chemical dioxide
dark side still remains.
So here, the most problematic of
the urate is its poor solubility.
When urate becomes insoluble,
that forms crystal.
And then crystal is in the
kidney that causes kidney stones.
And then if the crystal
forms in your joint,
that activates innate immunity
then leads to inflammation.
And this is a gouty attack.
