Effects Of 16-Week HIIT And Vitamin E Intervention On ROS-NF?B-Bnip3 Pathway In Aging Rats

Objective:The changes of ROS-NF?B-Bnip3 pathway and mitochondrial number in the soleus muscle of aged rats were observed and the HIIT intervention and vitamin E supplementation were performed for 16 weeks.The effects of HIIT intervention and vitamin E supplementation on the changes of these indicators were observed.Exercise provides a theoretical basis for regulating mitochondrial ROS-NF?B-Bnip-3 pathway to delay skeletal muscle age-related degeneration.Methods:Eighty 8-month-old male Wistar rats were randomly divided into a quiet group?group C?,a vitamin E supplement group?group EC?,a HIIT intervention group?group H?,and a HIIT-intervention vitamin E supplement group?group EH?,20rats in each group.The VO₂max test was performed 3 days after the adaptive training,and then the VO₂max test was performed every two weeks.The group H and the group EH were alternately performed at 50%,65%,and 80%VO₂max for 50 min/day,5days/week for 16 weeks of exercise intervention,and the exercise intensity was adjusted according to the VO₂max test result.Vitamin E was administered to the group EC and the group EH at 50 mg/kg body weight per day.Rats in each group were harvested at 24 hours after the end of the 8th week and the 16th week of the intervention.The rat soleus muscle was exfoliated.The fluorescence intensity of ROS was measured by a multi-function microplate reader.NF-?B,Beclin-1,Bnip-3 and PI3-k were tested by western blot.The expression of NF-?B,Beclin-1,Bnip-3 and PI3-k were observed by transmission electron microscopy to observe the morphological changes of rat soleus muscle mitochondria.VO₂max test results were analyzed by repeated measures analysis of variance,SOD,ROS test results and relative expression data of NF-?B,Bnip-3,Beclin-1 and PI3-k using SPSS for two-way analysis of variance.Results:1.During the 16 weeks,the number of mitochondria in the soleus muscle of the rats in group C decreased.The number of mitochondria in the soleus muscle of the rats in group H increased in the first 8 weeks and remained stable during the 8-16weeks.Rats in the group EC and the group EH showed a trend of increasing first and then decreasing.2.During the 16 weeks,the content of SOD in skeletal muscle of rats in group H and EH increased first and then decreased.The content of SOD in skeletal muscle of group C and group EC continued to decrease;Before group EC There was a slight decrease in 8 weeks and a significant drop in 8 to 16 weeks.3.During the 16-week period,the skeletal muscle ROS levels in the C and EH groups increased first and then decreased.By 16 weeks,the ROS content in the C and EH groups were higher than the basal state;the rats in the H and EC groups showed a continuous upward trend.In the first 8 weeks,the group H had a smaller increase than the group C.By 16 weeks,the skeletal muscle ROS content in the group H was basically the same as that in the group C.During the first 8 weeks,the skeletal muscle ROS level in the group EC increased significantly,16 weeks.The hourly level is basically the same as that of 8weeks.4.The changes of NF-?B protein content in the rats in each group were not obvious during the 16-week period,and the C group remained the same level;the H group showed a slight increase at 8 weeks,and then decreased to the basic state level at 16 weeks;The EC group NF-?B protein content in the rats in the first 8 weeks was basically unchanged,and increased slightly at 16 weeks.The EH group showed a slight decrease to below the basal state level in 0 to 8 weeks,and then increased in the 8-16weeks.Up to the basic state level.5.There was no change in Beclin-1 protein content in skeletal muscle of rats in group C during the 16 weeks;there was no change in the first 8 weeks of group H,and the content of Beclin-1 protein in skeletal muscle of rats increased from 8 to 16 weeks;The EC group and the EH group showed a trend of rising first and then decreasing,but the decline in the EH group was more obvious during the8-16 weeks.6.The content of Bnip-3 protein in group C and group EC showed a continuous upward trend during the 16-week period.Both the H group and the EH group showed a trend of increasing first and then decreasing.7.During the 16 weeks,the contents of PI3-k protein in skeletal muscle of rats in group C and EC showed a continuous upward trend,but there was no significant increase.The contents of PI3-k protein in skeletal muscle of rats in group H and EH showed The trend of rising first and then falling.Conclusion:1.HIIT intervention for 16 weeks can effectively delay the decrease of maximal oxygen uptake in aged rats,and delay the decline of aerobic capacity during the ageing.2.Vitamin E supplementation and HIIT intervention for 8 weeks can effectively delay the decrease of skeletal muscle mitochondria and morphological atrophy in aged rats.Simple vitamin E supplementation has no such effect.3.The HIIT exercise lasting for 16 weeks increased the number of mitochondria in the soleus muscle of the aged rats.The combination of HIIT exercise and vitamin E increased the mitochondrial volume of the soleus muscle of the aged rats but decreased the total number.4.HIIT intervention for 8 weeks and the combination of HIIT and vitamin E can delay the SOD content in rats and affect the protein content of ROS-NF?B-Bnip-3pathway,which may be the reason for alleviating skeletal muscle age-related degeneration.