Parvalbumin expression is downregulated in rat fast-twitch skeletal muscles during aging.
In this study, the protein expression profile of extensor digitorum longous (EDL) and Soleus (SOL) muscles, representing fast- and slow-twitch skeletal muscles, respectively, was established using high resolution two-dimensional electrophoresis (2-DE). One protein spot was found uniquely expressed in EDL muscle. N-terminal sequence analysis identified the protein as parvalbumin. Parvalbumin is a high affinity calcium binding protein that regulates muscle contraction and relaxation. Our experiments revealed that parvalbumin expression in EDL muscle was down-regulated during aging. In addition, high-intensity exercise could reverse this age-related change. Soleus muscles do not normally express parvalbumin, but high-intensity exercise could ectopically induce its expression in both young and old SOL muscles. We have also confirmed our 2-DE findings by immunohistochemistry on muscle sections. Our results suggest that high-intensity training could be used to improve muscle functions during aging because parvalbumin play an important role in regulating skeletal muscle contraction and relaxation.
Cai
D Q
DQ
Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Shatin, NT.
Li
M
M
Lee
K K
KK
Lee
K M
KM
Qin
L
L
Chan
K M
KM
D000375:Aging / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D015536:Down-Regulation / Q000502:physiology*; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D007150:Immunohistochemistry; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D018656:Muscle Fibers, Fast-Twitch / Q000737:chemistry / Q000378:metabolism*; D018657:Muscle Fibers, Slow-Twitch / Q000737:chemistry / Q000378:metabolism; D018482:Muscle, Skeletal / Q000737:chemistry / Q000378:metabolism*; D009218:Myosins / Q000737:chemistry; D010320:Parvalbumins / Q000737:chemistry / Q000378:metabolism*; D005082:Physical Exertion / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D020539:Sequence Analysis, Protein
D010320:Parvalbumins; D009218:Myosins