Infrared laser therapy decreases systemic oxidative stress and inflammation in ApoE knockout mice with periodontitis

Abstract

This study examines the effects of Photobiomodulation by near infrared irradiation (NIR-PBM) on oxidative and physiological stress in the apoliprotein E (ApoE-/-) knockout animal model with ligature-induced periodontal disease (PD). The animals were divided into three groups: ApoEC (without intervention); ApoEP (periodontitis); and ApoEP + L (periodontitis, NIR-PBM seven consecutive days). Alveolar bone loss (via scanning electron microscopy), quantification of reactive oxygen species (ROS) by flow cytometry, plasma cholesterol levels, inflammatory activity and plasma lipid peroxidation were evaluated. Alveolar bone loss was significant in the ApoEP group compared to the ApoEC group (p < 0.05). There was an increase in plasma cholesterol levels in the ApoEP group (p < 0.05) in relation to ApoEC; NIR-PBM reduced levels to levels below those of control animals. The ApoEP group had higher MPO levels when compared to the ApoEC group (p < 0.05). The superoxide anion and hydrogen peroxide increased in the ApoE P group in relation to the ApoEC (p < 0.05), ApoE P + L showed a reduction when compared to the ApoE P animals (p < 0.05) and the levels of hydrogen peroxide hydrogen were lower in the ApoEC group compared to ApoEP + L (p < 0.05). ApoEP group showed increased lipid peroxidation than ApoEC (p < 0.05), and animals that received NIR-PBM treatment had lower levels than ApoEP group (p < 0.05). In conclusion, NIR-PBM effectively reduces systemic parameters associated with PD progression in hypercholesterolemic animals. More studies with longer evaluation times are needed to elucidate the effects of PBM on experimental periodontitis related to hypercholesterolemia.