title: Helium-neon laser irradiation of cryopreserved ram sperm enhances cytochrome c oxidase activity and ATP levels improving semen quality.
abstract: This study examines whether and how helium-neon laser irradiation (at fluences of 3.96-9 J/cm(2)) of cryopreserved ram sperm helps improve semen quality. Pools (n = 7) of cryopreserved ram sperm were divided into four aliquots and subjected to the treatments: no irradiation (control) or irradiation with three different energy doses. After treatment, the thawed sperm samples were compared in terms of viability, mass and progressive sperm motility, osmotic resistance, as well as DNA and acrosome integrity. In response to irradiation at 6.12 J/cm(2), mass sperm motility, progressive motility and viability increased (P < 0.05), with no significant changes observed in the other investigated properties. In parallel, an increase (P < 0.05) in ATP content was detected in the 6.12 J/cm(2)-irradiated semen samples. Because mitochondria are the main cell photoreceptors with a major role played by cytochrome c oxidase (COX), the COX reaction was monitored using cytochrome c as a substrate in both control and irradiated samples. Laser treatment resulted in a general increase in COX affinity for its substrate as well as an increase in COX activity (Vmax values), the highest activity obtained for sperm samples irradiated at 6.12 J/cm(2) (P < 0.05). Interestingly, in these irradiated sperm samples, COX activity and ATP contents were positively correlated, and, more importantly, they also showed positive correlation with motility, suggesting that the improved sperm quality observed was related to mitochondria-laser light interactions.
authors.affiliation: Department of Agricultural, Environmental, and Food Sciences, University of Molise, Campobasso, Italy. Electronic address: nicolaia@unimol.it.
authors.forename: N
authors.initials: N
authors.lastname: Iaffaldano
authors.affiliation: Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, Campobasso, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Paventi
authors.affiliation: Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, Campobasso, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Pizzuto
authors.affiliation: Department of Agricultural, Environmental, and Food Sciences, University of Molise, Campobasso, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Di Iorio
authors.affiliation: Département des Sciences Animales, Centre de Recherche en Biologie de la Reproduction, Université Laval, Québec, Canada.
authors.forename: J L
authors.initials: JL
authors.lastname: Bailey
authors.affiliation: Department of Agricultural, Environmental, and Food Sciences, University of Molise, Campobasso, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Manchisi
authors.affiliation: Department of Medicine and Health Sciences "Vincenzo Tiberio", University of Molise, Campobasso, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Passarella
mesh_terms: D000255:Adenosine Triphosphate / Q000502:physiology*; D000818:Animals; D015925:Cryopreservation / Q000662:veterinary*; D003576:Electron Transport Complex IV / Q000378:metabolism*; D004789:Enzyme Activation / Q000528:radiation effects; D054020:Lasers, Gas; D008297:Male; D055101:Semen Analysis / Q000662:veterinary; D012662:Semen Preservation / Q000662:veterinary*; D012756:Sheep / Q000502:physiology*; D013094:Spermatozoa / Q000528:radiation effects*
chemical_list: D000255:Adenosine Triphosphate; D003576:Electron Transport Complex IV
keywords: ATP; Cryopreserved semen quality; Cytochrome c oxidase; Helium-neon laser; Ram sperm