3,5-Diiodo-L-thyronine (3,5-T2) is a thyroid hormone metabolite.¹It binds to thyroid hormone receptor α₁(TRα₁), TRβ₁, and TRβ₂(EC₅₀s = 0.8, 0.79, and 0.1 µM, respectively, in cell-free assays).²3,5-T2 (1 pM) stimulates oxygen consumption in perfused livers isolated from rats with hypothyroidism induced by sodium iodide.³It reduces subcutaneous and epididymal fat mass, as well as decreases serum leptin and cholesterol levels, without affecting body weight in high-fat diet-induced obese mice when administered at a dose of 2.5 µg/g per day.¹

1.Jonas, W., Lietzow, J., Wohlgemuth, F., et al.3,5-Diiodo-L-thyronine (3,5-T2) exerts thyromimetic effects on hypothalamus-pituitary-thyroid axis, body composition, and energy metabolism in male diet-induced obese miceEndocrinology156(1)389-399(2015) 2.Ball, S.G., Sokolov, J., and Chin, W.W.3,5-Diiodo-L-thyronine (T2) has selective thyromimetic effects in vivo and in vitroJ. Mol. Endocrinol.19(2)137-147(1997) 3.Horst, C., Rokos, H., and Seitz, H.J.Rapid stimulation of hepatic oxygen consumption by 3,5-di-iodo-?-thyronineBiochem. J.261(3)945-950(1989)