Evidence of melatonin synthesis by human lymphocytes and its physiological significance: possible role as intracrine, autocrine, and/or paracrine substance 1 ANTONIO CARRILLO-VICO * , JUAN R. CALVO * , PEDRO ABREU † , PATRICIA J. LARDONE * , SOFÍA GARCÍA-MAURIÑO * , RUSSEL J. REITER ‡ and JUAN M. GUERRERO * ,2 * Department of Medical Biochemistry and Molecular Biology, The University of Seville School of Medicine and Virgen Macarena Hospital, Seville, Spain; † Department of Physiology, School of Medicine, University of La Laguna, Tenerife, Spain; and ‡ Department of Cellular and Structural Biology, The University of Texas, Health Science Center at San Antonio, San Antonio, Texas, USA 2 Correspondence: Department of Medical Biochemistry and Molecular Biology, The University of Seville School of Medicine, Avda. Sánchez Pizjuan 4, 41009 Seville, Spain. E-mail: guerrero@us.es <h3>SPECIFIC AIMS</h3> It has been historically assumed that the pineal gland is the major source of melatonin in vertebrates. Melatonin plays a central role in fine tuning circadian rhythms in vertebrate physiology. Additionally, melatonin shows a remarkable functional versatility exhibiting antioxidant, oncostatic, anti-aging, and immunomodulatory properties. Its biosynthesis from tryptophan involves four well-defined intracellular steps catalyzed by tryptophan hydroxylase (TPH), aromatic amino acid decarboxylase (AADC),
/lp/fed-of-american-socs-for-experimental-biology/evidence-of-melatonin-synthesis-by-human-lymphocytes-and-its-s6fct50qqI