RAD-140 and Raloxifene Interaction: Avoid | Peptide Database

Join others researching Liothyronine (T3) — share findings, ask questions, and learn from real experiences Liothyronine (T3) is the biologically active form of thyroid hormone, responsible for regulating basal metabolic rate, thermogenesis, protein synthesis, and cellular energy metabolism throughout the body. Unlike levothyroxine (T4), which serves primarily as a prohormone requiring peripheral conversion by deiodinase enzymes, T3 acts directly on nuclear thyroid hormone receptors to exert its metabolic effects. It has been FDA-approved since the 1950s for the treatment of hypothyroidism, myxedema coma, and as a diagnostic agent in thyroid suppression tests. Pharmaceutical T3 is available as Cytomel (brand) and generic liothyronine sodium tablets. In performance and biohacking contexts, T3 is widely used during cutting phases to accelerate fat loss by directly upregulating metabolic rate, and by individuals seeking metabolic optimization when peripheral T4-to-T3 conversion is impaired due to caloric restriction, stress, or other factors. Liothyronine enters target cells via monocarboxylate transporter 8 (MCT8) and other thyroid hormone transporters, then binds to nuclear thyroid hormone receptors (primarily TR-beta in metabolic tissues and TR-alpha in cardiac tissue). The T3-receptor complex forms heterodimers with retinoid X receptors (RXR) and binds to thyroid hormone response elements (TREs) on DNA, directly modulating gene transcription. This increases expression of Na+/K+ ATPase (driving cellular energy expenditure), uncoupling proteins (UCP1 in brown adipose tissue, promoting thermogenesis), and enzymes involved in fatty acid oxidation, gluconeogenesis, and protein turnover. T3 also upregulates beta-adrenergic receptor density, which amplifies catecholamine sensitivity and contributes to increased heart rate, lipolysis, and thermogenesis. At physiological doses, T3 supports healthy metabolism; at supraphysiological doses, it shifts the body into a catabolic state where both fat and lean tissue can be catabolized for energy.

Join others researching Dutasteride — share findings, ask questions, and learn from real experiences Dutasteride is a potent dual 5-alpha reductase inhibitor that blocks both Type I and Type II isoforms of the enzyme responsible for converting testosterone to dihydrotestosterone (DHT). FDA-approved at 0.5mg daily for benign prostatic hyperplasia (BPH) under the brand name Avodart, it is widely used off-label for the treatment of androgenetic alopecia (male pattern hair loss). By inhibiting both isoforms, dutasteride achieves approximately 90% suppression of serum DHT, compared to roughly 70% with finasteride, which blocks only the Type II isoform. This greater DHT suppression translates to potentially superior hair regrowth outcomes in head-to-head comparisons, though it also carries a somewhat higher risk of DHT-related side effects. Dutasteride has an exceptionally long half-life of approximately 5 weeks, meaning it takes several months to reach steady-state levels and equally long for effects to fully wash out after discontinuation. Dutasteride competitively inhibits both the Type I and Type II isoforms of the enzyme 5-alpha reductase. Type II is the predominant isoform in the prostate and hair follicles, while Type I is found primarily in the skin, sebaceous glands, and liver. By blocking both isoforms, dutasteride suppresses serum DHT levels by approximately 90% at the standard 0.5mg dose, compared to the roughly 70% suppression achieved by finasteride (which blocks only Type II). This near-complete DHT suppression more effectively reduces the androgenic stimulus driving follicular miniaturization in genetically susceptible individuals. The exceptionally long elimination half-life of approximately 5 weeks is due to extensive tissue binding and slow clearance. Serum testosterone may increase modestly (10-20%) as a compensatory response to the pronounced reduction in DHT, though this increase remains within the normal physiological range for most men.