LONG version: Should we carry IGF-1 Des ?

**RUI-Products** · 03-16-2012, 08:47 AM

Note: there is a SHORT version of this in the aas section*
LONG version:

Should we carry IGF-1 Des ?

First off what is IGF-1 Des ?
Well it is kind of like a cross in between the standard (what your body produces and has been around as a peptide for sale, for a while now) IGF-1 and the altered and extended amino chain of IGF-1LR3.
The active live per dosing is similar as the IGF-1 but binds much better to the receptors, kind of like IGF1lr3.
The thing is the active life is not the same as LR3 yet the enhanced effectiveness is.
It is essentially your normal IGF-1 made for better binding/effecting to the IGF receptors.
Some people prefer IGF-1LR3 for their studies, while others prefer IGF-1.

Which version is better?
There are lots of debate on which is better, some argue more “injection site growth” with IGF-1 over IGF-1LR3. (Which I feel is minimal regardless of which side of the fence you’re on and should not be the main reason for your pick in my opinion)
Others argue the Short acting version (IGF-1) is safer, while others argue smaller doses of the long acting version maybe more so, due to less higher spikes in blood levels per administration.
I believe ether/or will work and have a great results in lab studies.
I feel it comes down more to preference, for e.g. one person might want to limite the amount of injections for their lab study with IGF-1 LR3, while another may want more overall control on the dosing and spikes of the test subject’s IGF levels.

But what about IGF-1 vs. IGF-1 Des?
One thing is for sure IGF-1 DES is better for binding to receptors than the “old school” IGF-1 on the market and there is a growing awareness of this.
That is why I am posting this up today as we want to make sure we supply our customers with the best quality, most popular and most useful peptides out there!
DES 1-3 has "approximately 10-fold more potent than IGF-1 at stimulating hypertrophy and proliferation of cultured cells" vs. endogenous IGF-1, due to DES 1-3's lack of affinity for IGFBPs.”

Now, dissecting that claim a bit, it's talking about hypertrophy and proliferation of CULTURED CELLS. This is NOT a human study I have based this statement on. Cultured cells are very different than a human being. And what does "potent" mean? There were no claims on DES 1-3's ability to generate 10x muscle mass gains in humans or even pigs etc. Just that the binding is obviously much better with IGF-1 Des over IGF-1.
Furthermore, Lr3IGF-1 was designed artificially to resist binding (deactivation) as is DES 1-3. I think it would be a great study would be to compare the "effectiveness" of these two at increasing muscle "hypertrophy" and/or "hyperplasia", but that’s another topic.
The DES 1-3 analog has a much lower affinity for IGF binding proteins (IGFBP) than IGF-1. Multiple studies have shown this.

Below are a few summaries of some studies on what I have already mentioned above:

Also, "Des (1-3) IGF is a deletion of the first 3 aa that fails to bind IGF-1 binding proteins (IGFBPs), which inactivate IGF-1. Authors of Endocr Dev. 2005;9:160-9 claim “IGFBPs inactivate IGF-I by forming inactive complexes. The uses of IGF analogues with low affinity for IGFBPs and analogues that are able to displace IGF-I from IGFBPs are better candidates (than IGF-1 itself) in new clinical trials. “"

Biochem. J. (1989) 258, 267-272 (Printed in Great Britain)
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Insulin -like growth factor (IGF)-binding proteins inhibit the biological activities of IGF-1 and IGF-2 but not des-(1-3)-IGF-1

Marina ROSS,* Geoffrey L. FRANCIS,* Laszlo SZABO,t John C. WALLACEt and F. John BALLARD*t
*CSIRO Division of Human Nutrition, Kintore Avenue, Adelaide SA 5000, and tBiochemistry Department,
University of Adelaide, SA 5000, Australia
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"The biological potencies of IGF-1, IGF-
2 and des-(1-3)-IGF-I correlate inversely with their binding to proteins released into the medium by cells,
so that the enhanced potency of des-(1-3)-IGF-1 is a consequence of it not binding to purified binding
Proteins or those released by cultured cells."

Des[1-3]-IGF-1
This protein has been isolated from bovine colostrum, human brain and porcine uterus. It is a truncated variant of human IGF-1 with an N-terminal deletion of the tripeptide Gly-Pro-Glu, which probably results from post-translational cleavage of IGF-1.

The protein binds less well to IGF-binding proteins and is generally approximately 10-fold more potent than IGF-1 at stimulating hypertrophy and proliferation of cultured cells.

REFERENCES: Ballard FJ Des(1-3)IGF-I: a truncated form of insulin-like growth factor-I. International Journal of Biochemistry and Cell Biology 28(10): 1085-1087 (1996)
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