title: Decreased melatonin levels and increased levels of advanced oxidation protein products in the seminal plasma are related to male infertility.
abstract: Melatonin, an indolamine secreted by the pineal gland, is known as a powerful free-radical scavenger and wide-spectrum antioxidant. Therefore, the aim of this study was to correlate markers of oxidative protein damage (advanced oxidation protein products, AOPPs) and the total antioxidant capacity (TAC) with melatonin levels in the seminal plasma of men with azoospermia (n=37), theratozoospermia (n=29) and fertile controls (normozoospermia, n=37). Melatonin concentration was measured by radioimmunoassay. The levels of AOPP as well as TAC efficiency (determined by the ferric reducing antioxidant power, FRAP) were estimated by spectrophotometric methods. The concentration of melatonin and AOPP significantly differed in azoospermic (P<0.0001) and theratozoospermic (P<0.0001) patients versus fertile men, and correlated negatively (r=-0.33, P=0.0016). The TAC levels were significantly higher in azoospermia than in theratozoospermia (P=0.0022) and the control group (P=0.00016). In azoospermia, the AOPP concentration was also significantly higher than that observed in theratozoospermia (P=0.00029). Decreased levels of melatonin together with elevated AOPP altered the oxidative-antioxidative balance in the ejaculate, thereby reducing fertility. Therefore, melatonin and AOPP levels may serve as additional diagnostic markers of semen quality and male reproductive potential.
authors.affiliation: Department of Chemistry and Immunochemistry, Faculty of Medicine, Wroc?aw Medical University, O. Bujwida 44A, 50-345 Wroc?aw, Poland.
authors.forename: Ewa Maria
authors.initials: EM
authors.lastname: Kratz
authors.affiliation: Department of Toxicology, Faculty of Pharmacy, Wroc?aw Medical University, Borowska 211, 50-556 Wroc?aw, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Piwowar
authors.affiliation: Department of Animal Physiology and Ethology, Faculty of Natural Sciences, Comenius University, Mlynska dolina B2, 84215 Bratislava, Slovak Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Zeman
authors.affiliation: Department of Animal Physiology and Ethology, Faculty of Natural Sciences, Comenius University, Mlynska dolina B2, 84215 Bratislava, Slovak Republic.
authors.forename: Katarína
authors.initials: K
authors.lastname: Stebelová
authors.affiliation: Institute of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Waehringer Guertel 18-20 Vienna, Austria.
authors.forename: Theresia
authors.initials: T
authors.lastname: Thalhammer
mesh_terms: D000328:Adult; D062107:Advanced Oxidation Protein Products / Q000032:analysis*; D053713:Azoospermia / Q000175:diagnosis / Q000378:metabolism*; D016022:Case-Control Studies; D015536:Down-Regulation; D006801:Humans; D008297:Male; D008550:Melatonin / Q000032:analysis*; D008875:Middle Aged; D018384:Oxidative Stress; D011863:Radioimmunoassay; D012661:Semen / Q000737:chemistry*; D013053:Spectrophotometry; D000072660:Teratozoospermia / Q000175:diagnosis / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D062107:Advanced Oxidation Protein Products; D008550:Melatonin