ABSTRACT
Objective To investigate the effect of red light on the expression of caspase-8 and caspase-3 mRNA and protein during the acute stage of hypoxic-ischemic brain damage (HIBD) in neonatal rats.Methods Forty-five seven-day-old Sprague-Dawley rats were randomly divided into a sham group,an HIBD model group (model group) and an irradiation group.The rats in the model and irradiation groups were subject to HIBD induced using the Rice-Vannucci method.The irradiation group was treated by irradiation with red light on the forehead immediately after the establishment of the HIBD model for 30 min/d on 3 consecutive days,while the sham group and the model group received no treatment.On the 3rd day after the operation,10 rats from each group were sacrificed by cervical dislocation and the left hippocampus was rapidly isolated and snap-frozen in liquid nitrogen for mRNA and protein examination.Another 5 rats in each group were used for immunofluorescence testing to localize and semi-quantify the expression of caspase-8 and caspase-3.Results In the model group,expression of caspase-8 and caspase-3 mRNA and protein in the left hippocampus was higher than in the sham group on the 3rd day.After red light irradiation,expression of caspase-8 and caspase-3 mRNA and protein decreased significantly in the irradiation group compared with the HIBD group.In the CA 1 region of the hippocampus,the levels of caspase-8 and caspase-3 in the irradiation group were significantly lower than in the model group.Conclusion Red light irradiation can decrease the expression of such apoptosis factors as caspase-8 and caspase-3 in hypoxic-ischemic brain damage at the acute stage and inhibit neural cell apoptosis so as to exert therapeutic effects for hypoxic-ischemic brain damage.
ABSTRACT
Objective To explore the therapeutic effects of 660 nm red light on sciatic nerve injury in adult rats.Methods Forty-five adult,male rats were divided into a control group and treatment groups 1,2,3 and 4.Sciatic nerve injury was modeled by crushing the nerve.The treatment groups received irradiation with red light once daily for 21 consecutive days.The power density of red light and irradiation time varied among the groups.The latency and amplitude of compound muscle action potentials (CMAPs) and nerve conductive velocity were examined at different time points.The Sciatic Function Index (SFI) was used to evaluate walking function.Results After 21 days of red light therapy no statistically significant differences were observed between the control group and treatment groups 1 to 4 with regard to the latency or the amplitude of the CMAPs.There was a significant difference between the control group and treatment group 3 in terms of sciatic nerve conduction velocity.The average Sciatic Function Indexes of treatment groups 2,3 were significantly different from that of the control group.Conclusion Red light irradiation can promote recovery after sciatic nerve injury,at least in rats,thereby improving walking function.