Increased iNOS, MMP-2, and HSP-72 in skeletal muscle following high-intensity exercise training.
Skeletal muscle adapts to exercise by an upregulation of cellular defenses, such as inducible nitric oxide synthase (iNOS) and matrix metalloproteinase type 2 (MMP-2) and heat shock protein type-72 (HSP-72). The aims of the study were to examine iNOS, MMP-2, and HSP-72 mRNA and protein expression after high-intensity exercise training and to examine whether the expression levels are fiber type dependent. Young Wistar rats were assigned to either 2 or 4 weeks of a high-intensity (32 m/min) running exercise for 40 minutes 5 day per week. A non-running group served as a control. Western blotting and reverse transcriptase-polymerase chain reaction of muscle mRNA and protein levels were assessed in the medial gastrocnemius, quadriceps, soleus, crural, and sternal head of diaphragm muscles. High-intensity exercise training for 4 weeks but not for 2 weeks resulted in a significant increase in both RNA and protein levels of iNOS, MMP-2, and HSP-72 in all muscles examined except the sternal head of diaphragm. High-intensity exercise training is required to promote the expression of iNOS, MMP-2, and HSP-72 in hind limb muscles regardless their muscle fiber type, whereas in the diaphragm the changes are fiber-type dependent.
Carmeli
Eli
E
Department of Physical Therapy, Sackler Faculty of Medicine, The Stanley Steyer School of Health Professions, Tel Aviv University, Ramat Aviv, Israel. elie@post.tau.ac.il
Beiker
Reut
R
Maor
Miri
M
Kodesh
Einat
E
D000818:Animals; D015153:Blotting, Western; D001835:Body Weight / Q000502:physiology; D003964:Diaphragm / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000096:biosynthesis / Q000235:genetics; D050884:HSP72 Heat-Shock Proteins / Q000378:metabolism*; D006614:Hindlimb / Q000378:metabolism; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism*; D009929:Organ Size / Q000502:physiology; D010805:Physical Conditioning, Animal / Q000502:physiology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction
D050884:HSP72 Heat-Shock Proteins; D012333:RNA, Messenger; D052247:Nitric Oxide Synthase Type II; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D020778:Matrix Metalloproteinase 2