Effects Of Astaxanthin And Acute High-intensity Exercise On Hepatic Oxidative Stress In Rats

Acute intense exercise induces excessive oxidative stress in the body,which causes certain damage to the metabolic function of the liver and the integrity of liver cells,and then produces secondary diseases.As a powerful antioxidant,astaxanthin plays an effective role in inhibiting the excessive generation of free radicals in the body,protecting the integrity of cell membrane,preventing oxidative injury caused by exercise and improving the body’s antioxidant capacity.Objective:To investigate the effects of astaxanthin supplementation on oxidative liver injury in rats induced by acute intense exercise and its mechanism.Methods:After adaptive feeding for 4 days,32 male SD rats were randomly divided into four groups:control group（group C）,single administration group（group M）,single exercise group（group E）,exercise and administration group（group EM）.Exercise intervention plan is:1 day after the grouping adaptive treadmill exercise in rats,constituting the 20th day exercise test,it is concluded that the rat exhaustion rate to an average of 21 m/min（75%VO₂max）,combined with the literature to determine the final run test plan for the last day,E EM group of rats with speed of 24 m/min,the slope as-16°,8group,each group for 5 min interval of 1 min acute large treadmill exercise intensity.The astaxanthin intervention scheme was as follows:M and EM groups were gavaged 25 mg/kg of astaxanthin daily for 4 weeks;Group C and E were given the same amount of soybean oil by gavage every day.Immediately after exercise collection of rat liver and femoral arterial blood,use kit determination of rat liver function index of ALT and AST level,oxidative stress,MDA,SOD and GSH levels,RT-q PCR method determination of liver tissue AMPKα1,AMPKα2,Nrf2,HO-1 m RNA expression quantity relatively,Western Blotting method hepatic AMPKαphosphorylation levels,GSK-3βand Nrf2,HO-1 protein phosphorylation level relative to express（/β-actin）.Results:The basal body weight of rats in four groups was similar,but no significant difference was found.Group E following acute intensive exercise rats serum ALT,AST activity increased significantly（P（27）0.01）;Cut down the content of serum MDA content increased,GSH（P（27）0.05）,but SOD vitality has no obvious change;The liver of rats increased amount of m RNA expression of HO-1（P（27）0.05）,other purpose gene m RNA expression quantity were no bigger difference;Hepatic AMPKαphosphorylation levels（P（27）0.05）,GSK-3βphosphorylation levels（P（27）0.01）and the decline in HO-1 protein expression.After astaxanthin intervention,the activity of ALT and AST had no changes.Lower plasma MDA content（P（27）0.01）,higher SOD activity（P（27）0.01）,GSH content has no obvious change;Rat liver AMPKα1,Nrf2,HO-1 m RNA expression quantity increases,AMPKα2 m RNA expression decreased,but without statistical significance;Hepatic AMPKαphosphorylation level and more Nrf2 protein expression（P（27）0.01）,GSK-3βphosphorylation levels（P（27）0.01）and HO-1 protein expression is on the decline.Astaxanthin supplement movement condition,the EM group rats serum ALT activity significantly decreased（P（27）0.01）and AST vitality has no obvious change;Plasma MDA content decreased significantly（P（27）0.05）,SOD activity significantly increased（P（27）0.01）,but have less effect on GSH content;Rat liver AMPKα1,the increased amount of m RNA expression of HO-1 but no significant difference,and AMPKα2,Nrf2 m RNA expression quantity has no obvious change;GSK-3βphosphorylation level in the liver tissue changed very significantly higher（P（27）0.01）,Nrf2 and HO-1 protein expression increased slightly and AMPKαphosphorylation levels drop but had no statistical significance.Conclusion:（1）The integrity of rat liver cells after acute intense exercise was damaged,which aggravated the degree of lipid peroxidation,decreased the activity of non-enzymatic antioxidant in the body,and induced oxidative stress injury;（2）Astaxanthin supplementation repaired liver cell membrane damage,significantly reduced the lipid peroxidation level in the membrane of rats under the state of rest and exercise,significantly increased the endogenous enzyme antioxidant level,and effectively protected against ROS-induced damage;（3）astaxanthin intervention by AMPKα1 pathway,to further promote the Nrf2 in nuclear transfer,push downstream transcription translation HO-1,enhance the body’s antioxidant defenses,but the quiet condition phase II detoxifying enzymes slight inhibitory effect on the expression of HO-1.