title: Accelerated skeletal muscle recovery after in vivo polyphenol administration.
abstract: Acute skeletal muscle damage results in fiber disruption, oxidative stress and inflammation. We investigated cell-specific contributions to the regeneration process after contusion-induced damage (rat gastrocnemius muscle) with or without chronic grape seed-derived proanthocyanidolic oligomer (PCO) administration. In this placebo-controlled study, male Wistar rats were subjected to PCO administration for 2 weeks, after which they were subjected to a standardised contusion injury. Supplementation was continued after injury. Immune and satellite cell responses were assessed, as well as oxygen radical absorption capacity and muscle regeneration. PCO administration resulted in a rapid satellite cell response with an earlier peak in activation (Pax7⁺, CD56⁺, at 4 h post-contusion) vs. placebo groups (PLA) (P<.001: CD56⁺ on Day 5 and Pax7⁺ on Day 7). Specific immune-cell responses in PLA followed expected time courses (neutrophil elevation on Day 1; sustained macrophage elevation from Days 3 to 5). PCO dramatically decreased neutrophil elevation to nonsignificant, while macrophage responses were normal in extent, but significantly earlier (peak between Days 1 and 3) and completely resolved by Day 5. Anti-inflammatory cytokine, IL-10, increased significantly only in PCO (Day 3). Muscle fiber regeneration (MHC(f) content and central nuclei) started earlier and was complete by Day 14 in PCO, but not in PLA. Thus, responses by three crucial cell types involved in muscle recovery were affected by in vivo administration of a specific purified polyphenol in magnitude (neutrophil), time course (macrophages), or time course and activation state (satellite cell), explaining faster effective regeneration in the presence of proanthocyanidolic oligomers.
authors.affiliation: Department of Physiological Sciences, Stellenbosch University, Stellenbosch, South Africa.
authors.forename: Kathryn H
authors.initials: KH
authors.lastname: Myburgh
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Kruger
authors.forename: Carine
authors.initials: C
authors.lastname: Smith
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D000975:Antioxidants / Q000032:analysis / Q000378:metabolism / Q000627:therapeutic use*; D019002:CD56 Antigen / Q000378:metabolism; D003288:Contusions / Q000178:diet therapy / Q000276:immunology / Q000473:pathology / Q000534:rehabilitation*; D016207:Cytokines / Q000097:blood / Q000378:metabolism; D019587:Dietary Supplements; D056604:Grape Seed Extract / Q000627:therapeutic use*; D008264:Macrophages / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008297:Male; D018482:Muscle, Skeletal / Q000276:immunology / Q000293:injuries / Q000473:pathology / Q000502:physiology*; D018995:Myosin Heavy Chains / Q000378:metabolism; D020556:Neutrophil Infiltration; D009504:Neutrophils / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D051761:Paired Box Transcription Factors / Q000378:metabolism; D059808:Polyphenols / Q000627:therapeutic use*; D044945:Proanthocyanidins / Q000627:therapeutic use*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012038:Regeneration; D032496:Satellite Cells, Skeletal Muscle / Q000276:immunology / Q000378:metabolism / Q000473:pathology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000975:Antioxidants; D019002:CD56 Antigen; D016207:Cytokines; D056604:Grape Seed Extract; C511402:Grape Seed Proanthocyanidins; C530821:PAX7 protein, rat; D051761:Paired Box Transcription Factors; D059808:Polyphenols; D044945:Proanthocyanidins; D018995:Myosin Heavy Chains