References CDC (2020)
in hypophysectomized rats) [32, 33]
This triggers protein kinase A, which upregulates thyroid hormone synthesis enzymes (thyroid peroxidase, sodium-iodide symporter), promoting T4 and T3 production
While passive diffusion was initially proposed as the main absorption route, recent evidence indicates that specific transmembrane transporters including Na-taurocholate cotransporting polypeptide, organic anion-transporting polypeptides, L-type amino acid transporters, and monocarboxylate transporters also facilitate LT4 uptake
Challenges include batch-to-batch variability, absence of standardized extraction protocols, and inconsistent concentrations of bioactive constituents, all of which complicate compliance with Good Manufacturing Practice (GMP) standards and hinder reproducibility in clinical trials
Ranieri M, Sciuscio M, Cortese AM, et al