Effects of photobiomodulation therapy (PBMT) on bovine sperm function.
Fertilization rates and subsequent embryo development rely on sperm factors related to semen quality and viability. Photobiomodulation therapy (PBMT) is based on emission of electromagnetic waves of a laser optical system that interact with cells and tissues resulting in biological effects. This interaction is mediated by photoacceptors that absorb the electromagnetic energy. Effects are dependent of irradiation parameters, target cell type, and species. In sperm, PBMT improves several features like motility and viability, affecting sperm aerobic metabolism and energy production. The aim of this study was to investigate, under same conditions, how different output powers (5, 7.5, and 10 mW) and time of irradiation (5 and 10 min) of laser (He-Ne laser, 633 nm) may affect frozen/thawed bovine sperm functions. Results showed significant effects depending on power while using 10 min of irradiation on motility parameters and mitochondrial potential. However, no effect was observed using 5 min of irradiation, regardless of power applied. In conclusion, PBMT is effective to modulate bovine sperm function. The effectiveness is dependent on the interaction between power applied and duration of irradiation, showing that these two parameters simultaneously influence sperm function. In this context, when using the same fluency and energy with different combinations of power and time of exposure, we observed distinct effects, revealing that biological effects should be also based on simple parameters rather than only composite parameters such as fluency, irradiance and energy. Laser irradiation of frozen/thawed bovine semen led to an increase on mitochondrial function and motility parameters that could potentially improve fertility rates.
Laboratory of Spermatozoa Biology, School of Veterinary Medicine and Animal Science, Department of Animal Reproduction, University of São Paulo, São Paulo, Brazil.
Adriano F P
AF
Siqueira
Laboratory of Spermatozoa Biology, School of Veterinary Medicine and Animal Science, Department of Animal Reproduction, University of São Paulo, São Paulo, Brazil.
Fernanda S
FS
Maria
Laboratory of Spermatozoa Biology, School of Veterinary Medicine and Animal Science, Department of Animal Reproduction, University of São Paulo, São Paulo, Brazil.|Laboratory of in vitro Fertilization, Cloning and Animal Transgenesis, School of Veterinary Medicine and Animal Science, Department of Animal Reproduction, University of São Paulo, São Paulo, Brazil.
Camilla M
CM
Mendes
Laboratory of Spermatozoa Biology, School of Veterinary Medicine and Animal Science, Department of Animal Reproduction, University of São Paulo, São Paulo, Brazil.
Thais R S
TR
Hamilton
Laboratory of Andrology, School of Veterinary Medicine and Animal Science, Department of Animal Reproduction, University of São Paulo, São Paulo, Brazil.
Andressa
A
Dalmazzo
Centro de Ciências Naturais e Humanas (CCNH), Federal University of ABC, Santo André, Brazil.
Thiago R
TR
Dreyer
Centro de Ciências Naturais e Humanas (CCNH), Federal University of ABC, Santo André, Brazil.
Herculano M
HM
da Silva
Laboratory of Andrology, School of Veterinary Medicine and Animal Science, Department of Animal Reproduction, University of São Paulo, São Paulo, Brazil.
Marcilio
M
Nichi
Centro de Ciências Naturais e Humanas (CCNH), Federal University of ABC, Santo André, Brazil.
Marcella P
MP
Milazzotto
Laboratory of in vitro Fertilization, Cloning and Animal Transgenesis, School of Veterinary Medicine and Animal Science, Department of Animal Reproduction, University of São Paulo, São Paulo, Brazil.
José A
JA
Visintin
Laboratory of Spermatozoa Biology, School of Veterinary Medicine and Animal Science, Department of Animal Reproduction, University of São Paulo, São Paulo, Brazil. meoaa@usp.br.
Mayra E O A
ME
Assumpção
D000818:Animals; D002417:Cattle; D002470:Cell Survival / Q000528:radiation effects; D028022:Low-Level Light Therapy / Q000379:methods*; D008297:Male; D055101:Semen Analysis; D012662:Semen Preservation; D013081:Sperm Motility / Q000528:radiation effects*; D013094:Spermatozoa / Q000528:radiation effects*
Flow cytometry; He-Ne laser; Low level laser therapy; Motility; Phothobiomodulatory effects