This is Pathetic…

Posted By elissa on Dec 11, 2008 | 0 comments

I’m currently writing a review of LG Sciences pSARM.  Evidently, the company is doing its best to convince would-be customers that the primary ingredient, osthol, binds to androgen receptors.  So one of their reps posted a drawing superimposing osthole over testosterone on a bbing board to “prove” it “fits” androgen receptors.*

There’s just (ahem!) a few problems with this argument…

1. Ligands – and their binding sites – are THREE-DIMENSIONAL – not two.  What LG Sciences has done is a bit like looking up at the night sky at a constellation, and assuming all the stars in a particular formation lie in the same plane, simply because that’s what it looks like from Earth.  2-D chemical formulas are simply a shorthand way of representing molecules, but like a painting or photograph, have no depth. Seemingly mall differences in structure can add up to large differences in shape – where it matters. And despite the alleged similarity, there are some pretty significant differences between the two.

2. If 2-D structural similarity is all that matters, there are plenty of other compounds that are a much closer match for testosterone than osthol is. Like estradiol (estrogen), for example. 😀

3. If 2-D structural similarity is all that matters, then perhaps the brain trust at LG Sciences would care to explain why many of the SARM drugs currently being researched have even less structural overlap w/testosterone than osthol does.

In short, it’s just marketing, and a rather weak attempt at that.  You “prove” androgen receptor binding capacity by – surprise!!! – conducting receptor binding studies (scroll down to “In Vitro and In Vivo Models for Evaluation of AR Ligands”) You “prove” a compound acts like a SARM by demonstrating it has tissue-selective effects. 

If you’re going to play “scientist,” then you need to play by the “rules.”  It’s that simple.

Pathetic.

*This drawing is referred to in the pSARM write up on their web site, but does not actually appear there. Maybe they finally realized just how thick it made them look.