Impairment of IGF-I expression and anabolic signaling following ischemia/reperfusion in skeletal muscle of old mice

► Aging muscle incurs greater damage following ischemia/reperfusion than in young. ► IGF-I expression in both peptide and mRNA of IGF-I were reduced in aging. ► Anabolic activity of aged muscle subsequent to injury was reduced compared to young. ► Aging reduced phosphorylation of intermediates of the PI3 Kinase pathway in muscle. ► Altered IGF-I signaling in aging muscle impairs recovery.