OLYMPUS UK YKAR1NE is an anabolic formulation containing (17α,20E)-17,20-[(1-methoxyethylidene)bis-(oxy)]-3-oxo-19-norpregna-4,20-diene-21-carboxylic acid methyl ester, or YK-11, a compound structurally similar to DHT, commonly classified as SARM, compounds selectively activating androgen receptors.
Androgen receptors (AR) are part of nuclear receptors responsible for the regulation of transcription of target genes. Being combined with "caring proteins" they wait inactive for the appearance of the corresponding androgen in the cytosol. The adoption of the ligand by AR allows the initial activation and translocation from the cytosol to the nucleus of the cell.
There, AR-androgen complex combines with the required DNA fragments (androgen response elements – ARE) and recruiting appropriate regulators, ie. co-activators or co-repressors, it respectively intensifies, or inhibits, the transcription of genes enabling the development and rehabilitation of concrete structures.
Full activation of AR is possible thanks to an interaction responsible for the transcription and joining coactivators of NTD domain (containing subdomain AF-1 – activation function-1) with LBD domain (having AF-2 subdomain – activation function-2), which has been called the N/C interaction.
The connection to the androgen receptors, there compete numerous compounds, including testosterone and dihydrotestosterone (DHT) – their excessive activity can lead to many adverse effects.
Through the activation of androgen receptors without inducing adverse effects, attributable to an excess number of androgens, there were emerged a newly formed group of compounds known as selective modulators of androgen receptors (SARMs).
SARM term refers to a group of substances, both steroidal and non-steroidal, which as ligands of androgen receptors (AR) connected to the hormone-binding domains (LBD) they affect their functioning.
Perfect SARMs are characterized by a big interaction strength of AR, typically bigger than endogenous androgens and tissue specificity, so that they are able to activate AR in selected areas of the organism, including muscles, bones, or the nervous system, with bypassing, e.g. prostate, leading to obtain desired effects.
As a rule, they are not a substrate for 5a-reductase and aromatase, and thus they are not subject to changes to DHT and estrogens, and therefore, they are not associated with negative consequences of the activity of these hormones.
(17α,20E)-17,20-[(1-methoxyethylidene)bis-(oxy)]-3-oxo-19-norpregna-4,20-diene-21-carboxylic acid methyl ester has been classified as one of the most effective SARMs, strongly activating anabolic processes in specific areas of the organism.
As the ligand having a tissue specificity and high affinity for AR (greater than in the case of testosterone or DHT), it is capable of strong binding to selected androgen receptors. Nevertheless, its operation not fully coincide with the one assigned SARMs, as evidenced by the inability to induce the N/C interaction, and therefore, a partial agonist of these receptors.
YK-11 irrespectively of a lack of possibilities to full activation of androgen receptors, it is able to increase the level of the main myogenic regulatory factors (MRFs), in particular: MyoD, Myf5 and myogenin, in a greater way than does it DHT. YK-11 enables a process of myogenesis mainly by increasing the concentration of follistatin (FST), through which it limits the activity of myostatin, a protein limitating muslce proliferation process over the naturally programmed size.
Besides the impact of (17α,20E)-17,20-[(1-methoxyethylidene)bis-(oxy)]-3-oxo-19-norpregna-4,20-diene-21-carboxylic acid methyl ester on androgen receptors and activating or inactivation of some proteins, so far there are not known an impact on the ratio of hormones in the organism and its possible effects on the liver.
OLYMPUS UK YKAR1NE is an extremely powerful anabolic product, which mainly through increasing MRFs and blocking myostatin, it is capable of increasing the synthesis of new muscle fibers. By supporting the development of muscle mass, with concomitant loss of excessive body fat, it leads to an exposure of an extremely muscular and skimmed silhouette.