title: Estimated Prestroke Peak VO2 Is Related to Circulating IGF-1 Levels During Acute Stroke.
abstract: Background Insulin-like growth factor-1 (IGF-1) is neuroprotective after stroke and is regulated by insulin-like binding protein-3 (IGFBP-3). In healthy individuals, exercise and improved aerobic fitness (peak oxygen uptake; peak VO2) increases IGF-1 in circulation. Understanding the relationship between estimated prestroke aerobic fitness and IGF-1 and IGFBP-3 after stroke may provide insight into the benefits of exercise and aerobic fitness on stroke recovery. Objective The purpose of this study was to determine the relationship of IGF-1 and IGFBP-3 to estimated prestroke peak VO2in individuals with acute stroke. We hypothesized that (1) estimated prestroke peak VO2would be related to IGF-1 and IGFBP-3 and (2) individuals with higher than median IGF-1 levels will have higher estimated prestroke peak VO2compared to those with lower than median levels. Methods Fifteen individuals with acute stroke had blood sampled within 72 hours of hospital admission. Prestroke peak VO2was estimated using a nonexercise prediction equation. IGF-1 and IGFBP-3 levels were quantified using enzyme-linked immunoassay. Results Estimated prestroke peak VO2was significantly related to circulating IGF-1 levels (r = .60; P = .02) but not IGFBP-3. Individuals with higher than median IGF-1 (117.9 ng/mL) had significantly better estimated aerobic fitness (32.4 ± 6.9 mL kg-1min-1) than those with lower than median IGF-1 (20.7 ± 7.8 mL kg-1min-1; P = .03). Conclusions Improving aerobic fitness prior to stroke may be beneficial by increasing baseline IGF-1 levels. These results set the groundwork for future clinical trials to determine whether high IGF-1 and aerobic fitness are beneficial to stroke recovery by providing neuroprotection and improving function.
authors.affiliation: University of Kansas Medical Center, Kansas City, KS, USA.
authors.forename: Anna E
authors.initials: AE
authors.lastname: Mattlage
authors.affiliation: University of Kansas Medical Center, Kansas City, KS, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Rippee
authors.affiliation: University of Kansas Medical Center, Kansas City, KS, USA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Abraham
authors.affiliation: University of Kansas Hospital, Kansas City, KS, USA.
authors.forename: Janice
authors.initials: J
authors.lastname: Sandt
authors.affiliation: University of Kansas Medical Center, Kansas City, KS, USA sbillinger@kumc.edu.
authors.forename: Sandra A
authors.initials: SA
authors.lastname: Billinger
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002545:Brain Ischemia / Q000378:metabolism / Q000473:pathology; D002543:Cerebral Hemorrhage / Q000378:metabolism / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D000066829:Neuroprotection; D010101:Oxygen Consumption / Q000502:physiology*; D010809:Physical Fitness / Q000502:physiology; D012720:Severity of Illness Index; D020521:Stroke / Q000378:metabolism* / Q000473:pathology
chemical_list: D015415:Biomarkers; C583557:IGF1 protein, human; C515497:IGFBP3 protein, human; D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I
keywords: acute; insulin-like growth factor I; physical fitness; stroke