[ExI] Jaw-dropping CWRU Alzheimer's breakthrough?

[spike]

-----Original Message-----
From: extropy-chat-bounces at lists.extropy.org
[mailto:extropy-chat-bounces at lists.extropy.org] On Behalf Of Jeff Davis
Sent: Thursday, March 15, 2012 2:03 PM
To: ExI chat list
Subject: Re: [ExI] Jaw-dropping CWRU Alzheimer's breakthrough?

On Wed, Mar 14, 2012 at 9:09 PM, spike <spike66 at att.net> wrote:

>>...we have a notion that bex somehow stimulates the mechanism which cleans
up beta amyloids, but it isn't a good barrier crosser, but other similar
medications are good crossers.

>...In several of your postings, Spike, you have mentioned that bex "isn't a
good barrier crosser".  These multiple assertions are liable to cause folks
to accept it as fact.  (Which it very well might be; links please.)
However, before that claim matures into solid belief, I have a couple of
questions:...In the CWRU research, the mice were administered bex, and it
"worked".
 So one might well ask, "If bex crosses the BBB only poorly, how come it
worked?"... Best, Jeff Davis


Jeff this is making me crazy, since the AD channels are smoking with
information but I don't know how to evaluate it.  What I understand is that
bexarotene is a lower crosser than some other similar medications, but
actual numbers are difficult to find.  The labs that have them aren't
talking.  Apparently substitution of a single COOH group with a methyl helps
it cross the barrier without harming its impact on beta amyloid mechanisms.
The problem with bexarotene is apparently the dose required to get
therapeutic levels in the brain cause a lot of side effects, especially in
those who have hypothyroid symptoms, which my family member does.  

However the medics know how to increase the crossing rate without wrecking
the medication, and are working the problem as fast as they can, and may it
be faster still.  Apparently the miraculous impact of bexarotene on mice is
not seen to the same degree in humans, or at least not nearly as quickly.
Damn.

UCLA and Salk have identified chemically related better crossers, but it
isn't clear that it is as effective as bexarotene was on the mice.  I am
hoping they publish soon.

spike