Lexica
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A SERD (Selective Estrogen Receptor Degrader), such as Fulvestrant, acts as a competitive antagonist that binds to the Estrogen Receptor (ER) and induces a conformational change. This misfolding causes the receptor to be flagged by the cell's proteasome system, leading to its proteasomal degradation (effectively 'recycling' the receptor as waste).
Fulvestrant has a significantly higher affinity for the ERα (Alpha) isoform. This is the 'master regulator' of epiphyseal closure and skeletal maturation; its absence prevents the mineralization of the growth plates and sutures. Crucially, this leaves the ERβ (Beta) isoform largely unblocked. While ERα drives feminization and skeletal fusion, ERβ is the primary mediator of neuroprotection, cardiovascular health, and trabecular bone mineral density (BMD).
The danger of standard AIs (Aromatase Inhibitors) is that they deplete the ligand (Estrogen) entirely, starving both receptors and causing cognitive decline and osteoporosis. By using Fulvestrant, we theoretically delete the 'fusion' receptor (ERα) while using Genistein Aglycone—a potent phytoestrogen with high ERβ-selectivity—to saturate the remaining receptors. This replicates the phenotype seen in clinical case studies of ERα deficiency, where individuals continue to grow linearly into their 30s due to the failure of estrogen-mediated skeletal 'sealing', while the ERβ-targeted Genistein maintains cognitive and metabolic homeostasis.
This strategy is modeled after the landmark 1994 case study of a 28-year-old male with a congenital ERα deficiency. Despite having normal-to-high levels of circulating testosterone and oestrogen, he stood 6'8" and was still growing because his body lacked the 'inbox' (ERα) to receive the signal to stop. His growth plates remained as open as a teenager's because the ERβ receptor alone was incapable of triggering the final 'seal'. By replicating this 'Selective Receptor Deletion', we aim to achieve a state of prolonged skeletal plasticity, allowing for 3D expansion and height growth to continue well beyond the natural developmental window."
However, it is important to note that the man in question had severe osteoporosis because the ERb receptor was not sufficient on its own to provide the necessary BMD.
Fulvestrant has a significantly higher affinity for the ERα (Alpha) isoform. This is the 'master regulator' of epiphyseal closure and skeletal maturation; its absence prevents the mineralization of the growth plates and sutures. Crucially, this leaves the ERβ (Beta) isoform largely unblocked. While ERα drives feminization and skeletal fusion, ERβ is the primary mediator of neuroprotection, cardiovascular health, and trabecular bone mineral density (BMD).
The danger of standard AIs (Aromatase Inhibitors) is that they deplete the ligand (Estrogen) entirely, starving both receptors and causing cognitive decline and osteoporosis. By using Fulvestrant, we theoretically delete the 'fusion' receptor (ERα) while using Genistein Aglycone—a potent phytoestrogen with high ERβ-selectivity—to saturate the remaining receptors. This replicates the phenotype seen in clinical case studies of ERα deficiency, where individuals continue to grow linearly into their 30s due to the failure of estrogen-mediated skeletal 'sealing', while the ERβ-targeted Genistein maintains cognitive and metabolic homeostasis.
This strategy is modeled after the landmark 1994 case study of a 28-year-old male with a congenital ERα deficiency. Despite having normal-to-high levels of circulating testosterone and oestrogen, he stood 6'8" and was still growing because his body lacked the 'inbox' (ERα) to receive the signal to stop. His growth plates remained as open as a teenager's because the ERβ receptor alone was incapable of triggering the final 'seal'. By replicating this 'Selective Receptor Deletion', we aim to achieve a state of prolonged skeletal plasticity, allowing for 3D expansion and height growth to continue well beyond the natural developmental window."
However, it is important to note that the man in question had severe osteoporosis because the ERb receptor was not sufficient on its own to provide the necessary BMD.
