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Equipoise: Better Left to the Horses

Citations for the video on boldenone, which you can watch here.

A. 17-beta-Boldenone, also 1-dehydrotestosterone and androsta-1,4-diene-17beta-ol-3-one, differs from 17-beta-testosterone by having only one double bond at the 1-position[1]. As a veterinary steroid, boldenone is produced with an undecylenate ester, which testosterone was once produced with also.

B. From a single injection of testosterone, undecylenate produces maximal androgenic effect in roosters (judged by the size of the comb on their heads) after 17 days, after which it slowly declines. For reference, propionate hits its max (lower than undecylenate) at 6 days[2].

C. Developed for human use as Parenabol[3].

D. Where testosterone has a 31% affinity to the human recombinant androgen receptor (as compared to 100% for dihydrotestosterone), boldenone has a 49% affinity. It has less than a 1/4th the affinity for the bovine progesterone receptor as testosterone and about 100x less than 19-nortesterone. It binds to recombinant human SHBG about 50% more than testosterone, but far less than 19-nortestosterone. The efficacy of boldenone to the human androgen receptor is unknown[4].

E. Boldenone is naturally produced in male animals, though it is not entirely clear how food and micro-organisms[5] affect its synthesis in animals[6].

F. Boldenone causes hepatic dysfunction in rabbits, elevating serum transaminase values (ALT and AST), which return to normal following discontinuation[7].

G. In rats, boldenone increased serum creatinine and LDL-C. Anti-nitrogen species phytochemicals from grapeseed extract reduced the cardiotoxicity of boldenone on rats[8].

H. Interestingly, moringa leaf extract has been shown to attenuate renal and hepatic damage due to boldenone[9].

I. Boldenone disrupts the HPG systems of rabbits, though it does not appear to harm sperm morphology[10].

J. Per mg, boldenone produced more acetylcholinesterase activity than controls and more than stanozolol (brand name Winstrol) and the effect was more pronounced with time. In the long-term, it produces more oxidative stress than stanozolol in the cerebral cortex and produced more aggressive behavior than stanozolol. It also worsened memory, unlike stanozolol[11].

[1] Stolker, A. A. M., Zuidema, T., & Nielen, M. W. F. (2007). Residue analysis of veterinary drugs and growth-promoting agents. TrAC Trends in Analytical Chemistry, 26(10), 967-979. [2] Biagi, G. L., Guerra, M. C., & Barbaro, A. M. (1970). Relation between lipophilic character and hemolytic activity of testosterone and testosterone esters. Journal of medicinal chemistry, 13(5), 944-948. [3] Melick, R. A., & Baird, C. W. (1970). The effect of “Parenabol” on patients with osteoporosis. Medical Journal of Australia, 2(21), 960-962. [4] Bauer, E. R. S., Daxenberger, A., Petri, T., Sauerwein, H., & Meyer, H. H. D. (2001). Characterisation of the affinity of different anabolics and synthetic hormones to the human androgen receptor, human sex hormone binding globulin and to the bovine progestin receptor. Apmis, 109(S103), S452-S460. [5] Tang, R., Shen, Y., Wang, M., Zhou, H., & Zhao, Y. (2019). Highly efficient synthesis of boldenone from androst-4-ene-3, 17-dione by Arthrobacter simplex and Pichia pastoris ordered biotransformation. Bioprocess and biosystems engineering, 42(6), 933-940. [6] De Brabander, H. F., Poelmans, S., Schilt, R., Stephany, R. W., Le Bizec, B., Draisci, R., ... & Macri, A. (2004). Presence and metabolism of the anabolic steroid boldenone in various animal species: a review. Food Additives and Contaminants, 21(6), 515-525. [7] Mayada, R. F., Taghred, M. S., & Haytham, A. A. (2015). Boldenone-induced apoptotic, structural, and functional alterations in the liver of rabbits. World Rabbit Science, 23(1), 39-46. [8] Tousson, E., Elgharabawy, R. M., & Elmasry, T. A. (2018). Grape seed proanthocyanidin ameliorates cardiac toxicity induced by boldenone undecylenate through inhibition of NADPH oxidase and reduction in the expression of NOX2 and NOX4. Oxidative medicine and cellular longevity, 2018. [9] Tousson, E., Hafez, E., Masoud, A., Ashour, R., & Ershidot, O. (2016). Modulation of boldenone induced hepatic and renal toxicity by Moringa oleiferaas in albino rats. Journal of Bioscience and Applied Research, 2(10), 686-694. [10] Oda, S. S., & El‐Ashmawy, I. M. (2012). Adverse effects of the anabolic steroid, boldenone undecylenate, on reproductive functions of male rabbits. International journal of experimental pathology, 93(3), 172-178. [11] Bueno, A., Carvalho, F. B., Gutierres, J. M., Lhamas, C., & Andrade, C. M. (2017). A comparative study of the effect of the dose and exposure duration of anabolic androgenic steroids on behavior, cholinergic regulation, and oxidative stress in rats. PLoS One, 12(6), e0177623.


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