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Dr Trevor Marshall
Foundation Staff
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Posted: Sat Dec 26th, 2009 09:37 |
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A new paper has just been published, which shows that only in the hands of master craftsmen are in-vitro and in-silico tools capable of delivering sensible results. Oh - unbiased master craftsmen, that is...
Here is the Pubmed abstract, loudly proclaiming that 25-D is a VDR agonist:
http://www.ncbi.nlm.nih.gov/pubmed/19944755
However, if you spend the money necessary to buy the full-text, a totally different picture emerges.
Take a look at Figure 1(c) below:
To make things simpler, and to make sure that we are posting this image in copyright 'fair-dealing' I have only included the graphic for 1(c).
Once you figure out how to read the figure  you can see the primary flaw in their argument - 25-D only started to induce significant transcription when it is at concentrations around 250nmol/L, or 100ng/ml. Which levels are of course toxic in-vivo.
Adams reported bone resorption occurring at 150nmol/L to 230 nmol/L
http://www.ncbi.nlm.nih.gov/pubmed/9245225
Now there are a number of other defects in this study which tend to distract from the essential value of what this group did - they confirmed that at physiological concentrations, 25-D is not a VDR agonist.
Which is a nice Christmas present indeed
..Trevor..
ps: 'Gold Stars' will be awarded to members who pick up the other defects in this study, especially to those who find ones I haven't noticed myself
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Dr Trevor Marshall
Foundation Staff
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Posted: Sat Dec 26th, 2009 10:07 |
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I wasn't suggesting everybody go out and buy a copy PM and email those who have one to share their copy...
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Rico
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Posted: Sat Dec 26th, 2009 12:26 |
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They're using samples from mice, not humans.
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No diagnosis/some symptoms; wife with Sarc on MP; Olm 40mg q6h| avoid D| 1,25D=63 25D=32 (May 2006) 1,25D=44; 25D=10(Dec 2006)PhaseI(May06) PhaseII(Aug06) PhaseIII(Aug07)
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Bane
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Posted: Sat Dec 26th, 2009 17:43 |
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| The focus is on 1 gene (Cyp24a1) of the 900+ the vdr may transcribe? From a point of logic wouldn't the body try and transform this high lvl of 25D (100ng/ml) into 24R, 25(OH)2D3 so it could be cleared from the body? That's if the vdr works, or is even present under the stress of pathogens. They are testing their hypothesis on vdr's thats working. Lookin at the figure they jump from 50nM with no effect, to 250nm(100ng/ml) with transcription effect, what if 25D starts producing Cyp24a1 allready at 100nM (40ng/ml), right where immunosuppression is in effect? So the Cyp24a1 production of a WORKIN vdr might be a defence mechanism from this toxic lvl? I see no AMP's, Cathelicidin or TLR2 produced??
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Oral Lichen Planus(mild)/Clubbed Finger (digital clubbing)Last 25D 5.6ng/ml, phase3
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Russ
Member in Phase 3
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Posted: Sat Dec 26th, 2009 18:09 |
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| I thought that agonism vs. antagonism was dependent on the structure of the molecule and how it fits into the binding pocket of the receptor. I wouldn't have thought that something could be antagonistic at low concentrations and agonistic at high concentrations. But from reading this thread it sounds like Vitamin D is an antagonist at normal physiological concentrations but turns into an agonist at super high concentrations (above the level of toxicity). Am I missing something?
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Lyme, MCS, ADD, optic nerve inflammation | Phase 1: Jul '06 | Phase 3: Jul '07 | 25D: 5 ng/ml (Oct '09)
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Dr Trevor Marshall
Foundation Staff
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Posted: Sat Dec 26th, 2009 20:10 |
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Russ, Bane and Rico you are right on the money. These authors show no production of CYP24 in a VDR null mouse, and then state this proves VDR transcribes CYP24. But no, that only proves VDR is one of the factors, not that it is the only one. Let me be clear, CYP24 is the enzyme I would probably check for, as it was found by Wang et al to be the most highly up=regulated. But I know that one gene is not enough - even measuring cathelicidin may not substitute for the Beta-defensins, TLR2, etc. A simplistic model of how the body works is the enemy of goood science...
At the recent Nuclear Receptors conference it was stated that whole-genome luciferase scans were showing that VDR transcribes several hundred without a ligand at all, and several thousand when liganded.The Foundation is in discussion to test Olmesartan with this assay, and we have ordered some pure olmesartan (not medoxomil) from China so we can get this data - how many thousands of genes are involved?
The fundamental advantage of in-silico molecular emulation is that it models the forces between atoms, and determines shape and affinity based on that. Why a self-respecting scientist would be thinking in terms of "pocket volume" and "filling the pocket" rather than the forces exerted by one molecule on another, is beyond my comprehension. And a sad statement on the quality of in-silico research. No wonder people say it isn't a reliable technology - it seems that the competence of the researcher is important. Sigh. Take a look at:
http://autoimmunityresearch.org/flash/Olmesartan_VDRh_VDRm.html
http://autoimmunityresearch.org/flash/VDR_activation.html
The second video was made when I finally realized exactly how the VDR activates when using a DRIP205 coactivator - something which apparently nobody else has figured out yet  Precision is the keyword.. and lots of computing power...
Finally, there is no attempt to quantify, or take into account, all the other effects that 1,25-D and 25_d have on other receptors, raging from Rhodopsin in the eye (which was a doddle to figure out after thinking about 'floaters' for a while...) to GPCRs and the other nuclear receptors.
And then there is the mistake confusing the mouse VDR with the human VDR. Several papers have exposed that mistake in the past...
I could go on and on - maybe after breakfast...
ps:why did they discount the concentrations of 1,25-D in the skin at 800pmol as not being important. Haven't they ever looked at the decades of range covered by an S-shaped displacement curve?
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Russ
Member in Phase 3
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Posted: Sat Dec 26th, 2009 20:24 |
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So the correct data, from your work, shows that 25D is a VDR antagonist regardless of concentration?
What's the difference between pure olmesartan and olmesartan medoxomil?
Thanks.
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Lyme, MCS, ADD, optic nerve inflammation | Phase 1: Jul '06 | Phase 3: Jul '07 | 25D: 5 ng/ml (Oct '09)
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Bane
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Posted: Sat Dec 26th, 2009 20:56 |
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Russ wrote: So the correct data, from your work, shows that 25D is a VDR antagonist regardless of concentration?
What's the difference between pure olmesartan and olmesartan medoxomil?
Thanks.
i don't think it's that black and white, they experimented with cell line and mice. High concentrations of 25D will leak/find it's way into the cell, high 1.25 will leak out from tissues thats inflamed/infected. Once inside the cell 25D will occupy the LBP, and according to this study they say 25D will transcribe 1 gene, while 1.25D is said to transcribe over 900, even olmesartan probably can't compete with that
Olmesartan medoxomil is the prodrug form
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Oral Lichen Planus(mild)/Clubbed Finger (digital clubbing)Last 25D 5.6ng/ml, phase3
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Dr Trevor Marshall
Foundation Staff
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Posted: Sat Dec 26th, 2009 21:09 |
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Olmesartan medoxomil is a prodrug, converted to the biologically-active olmesartan by esters in the blood and GI tissue.
The primary difference seems to be that olmesartan medoxomil, the pharmaceutical marketed by Sankyo, is a pharmaceutical marketed by Sankyo. The medoxomil moeity does extend the 'hypotensive efficacy' to 24 hours between dosing, something probably not too important to MP members
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Dr Trevor Marshall
Foundation Staff
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Posted: Sat Dec 26th, 2009 21:32 |
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Bioactive Olmesartan (white powder) is CAS: 144689-24-7
http://www.chemblink.com/products/144689-24-7.htm
(8 suppliers listed)
Olmesartan medoxomil (white powder) is CAS:144689-63-4
http://www.chemblink.com/products/144689-63-4.htm
(wow - 35 suppliers..)
Olmesartan with an extra CH2 group and unknown equivalence is CAS: 144689-78-1
http://www.chemblink.com/products/144689-78-1.htm
Trityl Olmesartan, which is 'easily' converted to very pure Olmesartan medoxomil is CAS: 144690-92-6
http://www.chemblink.com/products/144690-92-6.htm
(patent explaining how to convert is at http://tinyurl.com/ybdddpu )
Last edited on Sat Dec 26th, 2009 21:36 by Dr Trevor Marshall
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inge
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Posted: Sun Dec 27th, 2009 07:21 |
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Trevor,
Do you plan to comment on the flaws of the article in the journal where it is published? If not I might do it.
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CFS/ME 125D64 25D12(dec 07) Ph1De06 daily lite exp NoIR use Ph2Mar07 ModPh2 Jun07 abx brkOct 07 r//t KFTs freq abx chg to control kidney IP Apr 08 phase 2 abx
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marysue
Moderator
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Posted: Thu Dec 31st, 2009 05:30 |
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What are "whole-genome luciferase scans" and who is using them in the research world--and for what purposes?
Anything with the term "whole-genome" in it sounds pretty interesting and useful.
MarysueLast edited on Thu Dec 31st, 2009 05:32 by marysue
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Thanks Dr. Marshall and staff for all the support!
CFS/FM '95; infert/endomet '02; hypotension; cardiac IP; start light restrict. Oct08; 125D=70 25D=30 (Feb09); Benicar26Apr09; NoIRs, low light, no sun; 25D=10 (Jun09); 25D=5 (Nov09)
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Dr Trevor Marshall
Foundation Staff
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Posted: Sat Jan 2nd, 2010 23:41 |
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Inge,
Sorry, I missed your answer while I was in China.
Paul has written to the editor asking if he might like a comment. There doesn't seem to be a way of dealing with a detailed critique at the publication, so a short letter from a physician (you) might be rather helpful, regardless of whether we eventually put a larger document together
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sdcreacy
Member in Phase 3
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Posted: Wed Jan 6th, 2010 03:12 |
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A methodological problem with Figure 1(C):
They use MCF-7 cells, a Her2(-) human breast cancer cell line that is nothing close to normal. This cell line, like all long term cell cultures-particularily cancer cell lines- have massively rearranged genomes and mutated gene expessions. MCF-7 could hardly be considered a normal human system. A massive overdose of a seco-steroid would have unknown cross-pathway effects. While not perfect, a low-passage primary human cell line would have been preferable in this experiment.
Figures A and B refer to mouse CYP24a1 and VDR, so- as we know- do not precisely represent human biochemistry.
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sdcreacy
Member in Phase 3
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Posted: Wed Jan 6th, 2010 03:23 |
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| Quick question regarding Olmesartan: are there any references I could read that establish Olmesartan as a VDR agonist biochemically (in-vitro or in cells)? The 2006 paper calls it an antagonist, so I am confused.
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jcwat101
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Posted: Wed Jan 6th, 2010 03:45 |
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We don't have in vitro data as of yet.
That article is superceded by the work Trevor presented here:
Karolinska Institut “Days of Molecular Medicine-Inflammation in Chronic Disease” Conference in Stockholm, Sweden, May 24-27, 2006.
Dr. Marshall's presentation VDR Nuclear Receptor Competence is the Key to Recovery from Chronic Inflammatory and Autoimmune Disease explains how Benicar activates the innate immune system.
Available at:
http://www.marshallprotocol.com/forum39/5940.html
http://www.marshallprotocol.com/forum39/6362.html
A copy of the handout is available from URL http://autoimmunityresearch.org/karolinska-handout.pdf
Of course we do have our clinical, in vivo data, supporting this role for Olmesartan. The indirect evidence is discussed some here http://autoimmunityresearch.org/preprints/WaterhouseAnnals2009Preprint.pdf
and in the other papers and presentations at http://mpkb.org
Joyce Waterhouse
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20 yrs with CFS/FM/Lyme/IBS, food sensitivities; 1,25D/25D 8/04:64/11 http://SynergyHN.com
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Frans
Member in Phase 2
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Posted: Wed Mar 3rd, 2010 15:51 |
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Trevor,
I just ran into this paper: PMID 20193763
It is a study way over my head, but the following stands out:
The expressed enzyme (Frans: mouse CYP27B1) has low activity at higher concentrations of 25-hydroxyvitamin D in membranes, revealing that substrate inhibition may contribute to the regulation of the activity of this enzyme
Best, Frans
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Burn-out/nervous breakdown Jan01 125D 48 25D8.48 Ph1Nov06 ModPh2Jan07 Ph2Apr08 Cipramil Seroquel NoIRs lite exp r/t work cover up 25D3.9(Oct07)
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Dr Trevor Marshall
Foundation Staff
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Posted: Wed Mar 3rd, 2010 18:55 |
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Frans,
If you look at Figure 1 in my Bioessay you will see the specific contributions to this enzyme.
http://TrevorMarshall.com/BioEssays-Feb08-Marshall-Preprint.pdf
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