title: Impact of cigarette smoking on histone (H2B) to protamine ratio in human spermatozoa and its relation to sperm parameters.
abstract: Smoking is strongly associated with abnormalities in histone-to-protamine transition and with alteration of protamine expression in human spermatozoa. A proper protamine to histone ratio is, however, essential for sperm chromatin maturity and DNA integrity. Alterations in these sperm nuclear proteins were observed in infertile men. The present prospective study is aimed at evaluating the possible relationship among smoking, semen quality and the histone-to-protamine transition ratio in mature spermatozoa. Histone H2B and protamine 1 (P1) and 2 (P2) were quantified using acid-urea polyacrylamide gel electrophoresis in the spermatozoa of 35 smokers and 19 non-smokers. Levels of lipid peroxidation marker malondialdehyde (MDA) were measured in seminal plasma by thiobarbituric acid assay. Cotinine concentrations were determined in seminal plasma using an enzyme-linked immunosorbent assay. Histone H2B levels in smokers (292.27 ± 58.24 ng/10(6)) were significantly higher (p = 0.001) than that of non-smokers (109.1 ± 43.70 ng/10(6)), besides, a significant difference (p > 0.0001) was found for the P1 and P2 ratio between smokers (1.71 ± 0.071) and non-smokers (1.05 ± 0.033). The H2B/(H2B+P1 + P2) ratio (0.29 ± 0.71) of smokers were significantly higher (p = <0.0001) than that of non-smokers (0.12 ± 0.01). The concentrations of MDA (μm) (7.13 ± 1.15) and cotinine (ng/mL) (60.44 ± 31.32) in seminal plasma of smokers were significantly higher (p = 0.001) than those in the samples of the non-smoker group (4.42 ± 1.16 and 2.01 ± 2.84 respectively). In addition, smokers showed significantly (p ≤ 0.002) lower sperm count, motility (p = 0.018), vitality (p = 0.009) and membrane integrity (p = 0.0001) than non-smokers. These results reveal that patients who smoke possess a higher proportion of spermatozoa with an alteration of the histone to protamine ratio than patients who do not smoke, and suggest that cigarette smoking may inversely affect male fertility.
authors.affiliation: Department of Basic Sciences, College of Science and Health Professions, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia; Department of Medical Biochemistry & Molecular Biology, University of the Saarland, Homburg/Saar, Germany; IVF & Andrology Laboratory, Department of Obstetrics and Gynecology, University of the Saarland, Homburg/Saar, Germany; Faculty of Pharmacy and Medical Sciences, Petra University, Amman, Jordan.
authors.forename: M F
authors.initials: MF
authors.lastname: Hamad
authors.forename: N
authors.initials: N
authors.lastname: Shelko
authors.forename: S
authors.initials: S
authors.lastname: Kartarius
authors.forename: M
authors.initials: M
authors.lastname: Montenarh
authors.forename: M E
authors.initials: ME
authors.lastname: Hammadeh
mesh_terms: D000328:Adult; D002470:Cell Survival; D002843:Chromatin / Q000235:genetics; D003367:Cotinine / Q000378:metabolism; D005298:Fertility / Q000187:drug effects*; D006657:Histones / Q000378:metabolism*; D006801:Humans; D007248:Infertility, Male; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D011446:Prospective Studies; D011479:Protamines / Q000378:metabolism*; D012661:Semen / Q000737:chemistry; D055101:Semen Analysis; D012907:Smoking / Q000009:adverse effects*; D013076:Sperm Count; D013081:Sperm Motility / Q000187:drug effects*; D013094:Spermatozoa / Q000187:drug effects
chemical_list: D002843:Chromatin; D006657:Histones; C082073:PRM1 protein, human; D011479:Protamines; C068621:protamine 2; D008315:Malondialdehyde; D003367:Cotinine
keywords: histones; oxidative stress; protamines; smoking; sperm parameters