Trenbolone and cytotoxicity

[Serotonin]

Was browsing some online journals from my universities proxy and found this about tren... kind of interesting!

The anabolic steroids trenbolone and tetrahydrogestrinone induce micronuclei in V79 cells

Susanne B. Dorn , Hermann M. Bolt, Gisela H. Degen
Institute for Occupational Physiology, University of Dortmund, Germany


Anabolic steroids are used as growth promoter in animal husbandry, but are also widely misused by athletes for doping. Besides their hormonal (androgenic) potency, the possibility of genotoxic properties raises concern. The synthetic androgen trenbolone and the structurally related tetrahydrogestrinone were studied for chromosomal genotoxicity. Trenbolone (TB) has been evaluated previously in a series of in vitro and in vivo assays. Although it apparently binds to DNA and proteins to some extent, equivocal results have been obtained for cell transformation, and in assays reflecting genotoxicity at the chromosomal level. The genotoxicity of the newly synthesized designer drug tetrahydrogestrinone (THG) has not been investigated at all.

We determined the potency for micronucleus induction in V79 cells of TB and THG in comparison to the natural androgen testosterone. The cytotoxicity of the compounds was also assessed by means of the Alamar-Blue assay. All three compounds were cytotoxic at concentrations above 30 μM. Testosterone did not cause an induction of micronuclei up to 300 μM. In contrast, TB and THG induced micronuclei in V79 cells at subcytotoxic concentrations, THG being clearly more potent: it caused almost a doubling of the micronucleus rate at 3 μM; for TB, a two-fold increase of the MN rate was detected at 23 μM. The micronuclei induced by TB and THG were predominantly kinetochor (CREST)-positive, characterising the chromosomal genotoxicity as aneugenic. Since both TB and THG contain activated conjugated double bonds, they are expected to bind to proteins, e.g. tubulin, and may thereby disturb functions of the spindle apparatus.

Against this background, a specific mechanism of MN induction by TB and THG is proposed, since a plot of effective concentration against lipophilicity (−log C versus log Pow) reveals that both compounds are more potent than expected for non-specific hydrophobic interactions.

Here is a definition for aneugenic which is the KEY word in this abstract...

Aneugenic- Agents which affect CELL DIVISION and the MITOTIC SPINDLE APPARATUS resulting in the loss or gain of whole CHROMOSOMES, thereby inducing an ANEUPLOIDY.

[Conciliator]

As someone pointed out to me, the V79 cell line is Chinese hamster lung cell fibroblasts. They appear to really suck for making conclusions about human genotoxicity: http://www.pubmedcentral.nih.gov/pic...8&blobtype=pdf

[Serotonin]

Wow, man awesome read! Kind of hilarious that so much research would be done on a cell line with a mutated p53 gene!

Although it doesn't really affect the study that I cited since they weren't specifically looking at DNA damage or repair but the trenbolone binding to tubulin and disrupting the splitting of chromosomes during mitosis. This study probably used the v79 cell line since it has a very short generation time.

Thanks again for the info though, definitely interesting!

[Mike Dura]

I read the abstract and it's very technical and specialized which is great for the initiated but not for the generalist (i.e., 99% of the readers here). The jargon seems to be for those who have an advanced background in Bio? Frankly, I wouldn't even know if you understand it as it seems some pretend on this board (just like in day to day life). I catch people doing this in areas I am versed in - they just kind of fake it so others can bear witness to their efficacy and "knowlege."

Who knows? Maybe you do truly understand it. If so, talk in more general terms so others can grasp the content. In other words, consider the audience.

Now what I (a non-specialist in this area) got out of it is that tren can alter DNA. Mitosis is something I vaguely recall from a Bio class, roughly the process of a cell reproducing itself? That's probably wrong. One question is, how is this relevant to the tren user? Permanently altered genes? What are the ramifications if any?

Wow, man awesome read! Kind of hilarious that so much research would be done on a cell line with a mutated p53 gene!

Although it doesn't really affect the study that I cited since they weren't specifically looking at DNA damage or repair but the trenbolone binding to tubulin and disrupting the splitting of chromosomes during mitosis. This study probably used the v79 cell line since it has a very short generation time.

Thanks again for the info though, definitely interesting!

[Serotonin]

Mike- I understand what you mean but I'm sure there are some people that do read this and can glean a decent amount of info from it. I'm sure most people are confused by a lot of the jargon, as am I since I'm only just no finishing my bachelor's. Mainly, I put the info out for those interested and will always answer any questions I can!

Basically, the Trenbolone molecule will bind to protein molecules. Specifically, this article focused on that aspect and its affinity for the tubulin protein. The tubulin protein makes up the spindle fibers that will form and connect to chromosomes during metaphase of mitosis. This is the phase in which chromosomes line up in the middle of the cell. The next stage of mitosis is anaphase in which the duplicate chromosomes are pulled apart at their centromere. This study suggests that the trenbolone interferes with tubulin so much that perhaps a chromosome will NOT split thus leading to a new cell that will have a missing chromosome- also known as aneuploidy.

Now, under most circumstances this wouldn't matter anyways since it would most likely occur in a somatic cell (any cell of the body aside from sex cells like a sperm or an egg). The cell would probably not function and would either undergo apoptosis (programmed cell death) or be marked and destroyed by the immune system.

From what I learned, and hoped to convey to any readers, was that sometimes a chromosome can be missing and the cell may still function but actually be missing tumor suppression genes that may have been on the missing chromosome. This can lead to uncontrolled cell division which then can lead to further mutations and possibly cancer.

Ultimately, I'm sure the risk is negligible but it is there none the less and perhaps another anabolic may be better in the long run than trenbolone. I've done no research on this stuff but just found this article interesting enough to pass along.

[Serotonin]

As a side note, I'm still interested in trying tren in a future cycle but definitely won't be using it for a long time or multiple cycles.

[Conciliator]

This probably has more applicability:

http://www.ncbi.nlm.nih.gov/entrez/q...=pubmed_docsum

Ann Rech Vet. 1991;22(3):257-62.
Trenbolone: application of the Ames test. Recent data.Marzin D.
Laboratoire de Toxicologie, Institut Pasteur de Lille, France.

The mutagenicity of trenbolone, a synthetic androgen, was studied in a number of genotoxicity tests using in vitro and in vivo systems for gene mutations, chromosomal mutations and primary DNA damage demonstration. Only 2 tests were found to be positive or dubious: the in vitro micronucleus test in SHE cells (however, this test was negative in 2 other cell lines: C3H and CHO cells) and the Ames test for 1 of the 5 studies which found a positive result in TA 100 strain without metabolic activation. Repetition of this study with pure trenbolone showed no genotoxic activity; trenbolone was therefore considered to be devoid of genotoxic activity.

PMID: 1952760 [PubMed - indexed for MEDLINE]

[Conciliator]

Also:

http://www.ncbi.nlm.nih.gov/entrez/q...=pubmed_docsum

Arch Toxicol. 1988;61(4):249-58. Links
The genotoxicity of trenbolone, a synthetic steroid.Richold M.
Huntingdon Research Centre, Cambs, England.

Trenbolone, a synthetic androgen is used as a growth promotant in animal husbandry. Because of its steroidal structure and properties it has been extensively evaluated in a series of in vitro and in vivo assays to assess its genotoxic and initiating properties. Both the parent molecule 17-beta-hydroxy-trenbolone and its metabolite 17-alpha-hydroxy-trenbolone, produced only in cattle, have been tested. 17-beta-hydroxy-trenbolone was not genotoxic in the Ames Salmonella/microsome assay, cytogenetics assays in human lymphocytes and CHO cells, a micronucleus assay in CHO cells, a DNA repair synthesis assay in HeLa cells, mammalian cell mutation assays with CHO and V79 cells, the mouse micronucleus assay, rat bone marrow or spermatogonial cytogenetics assays or in a test for initiators in the rat. In the mouse lymphoma cell mutation assay with L 5178Y TK+/- cells, equivocal responses were obtained, particularly at highly toxic concentrations. With 17-alpha-hydroxy-trenbolone a weak positive response was obtained in the L5178Y Tk +/- assay, particularly at highly toxic concentrations. Negative results were obtained in the Ames Salmonella/microsome assay, the cytogenetics assays using both human lymphocytes in vitro and rat bone marrow in vivo, the DNA repair assay and in the CHO mammalian cell mutation assay. It was also negative in the in vivo test for initiators. From this extensive battery of data, and also taking into account published data on trenbolone, it is concluded that 17-alpha-hydroxytrenbolone and 17-beta-hydroxy-trenbolone are devoid of genotoxic activity and are not initiators of cancer.

PMID: 3288174 [PubMed - indexed for MEDLINE]

[Serotonin]

Awesome! I wish it stated the dosages. I found a few more that were interesting and will post them tonight when I get out of work. Hopefully tomorrow I can fish around for some more information on it binding to tubulin.

Thanks Conciliator!

[Mike Dura]

Thanks for breaking it down for me. You obviously study this stuff. Good info. It sounds like the risks would be small for a single cycle.

Mike- I understand what you mean but I'm sure there are some people that do read this and can glean a decent amount of info from it. I'm sure most people are confused by a lot of the jargon, as am I since I'm only just no finishing my bachelor's. Mainly, I put the info out for those interested and will always answer any questions I can!

Basically, the Trenbolone molecule will bind to protein molecules. Specifically, this article focused on that aspect and its affinity for the tubulin protein. The tubulin protein makes up the spindle fibers that will form and connect to chromosomes during metaphase of mitosis. This is the phase in which chromosomes line up in the middle of the cell. The next stage of mitosis is anaphase in which the duplicate chromosomes are pulled apart at their centromere. This study suggests that the trenbolone interferes with tubulin so much that perhaps a chromosome will NOT split thus leading to a new cell that will have a missing chromosome- also known as aneuploidy.

Now, under most circumstances this wouldn't matter anyways since it would most likely occur in a somatic cell (any cell of the body aside from sex cells like a sperm or an egg). The cell would probably not function and would either undergo apoptosis (programmed cell death) or be marked and destroyed by the immune system.

From what I learned, and hoped to convey to any readers, was that sometimes a chromosome can be missing and the cell may still function but actually be missing tumor suppression genes that may have been on the missing chromosome. This can lead to uncontrolled cell division which then can lead to further mutations and possibly cancer.

Ultimately, I'm sure the risk is negligible but it is there none the less and perhaps another anabolic may be better in the long run than trenbolone. I've done no research on this stuff but just found this article interesting enough to pass along.

[Mike Dura]

Hey guys. When you post these interesting things be sure to throw the non-specialist a bone. We're interested too. LoL.