Impact of alpha‐tocopherol deficiency and supplementation on sacrocaudalis and gluteal muscle fiber histopathology and morphology in horses

Journal of Veterinary Internal Medicine

Janel Peterson¹  Anna Dahlgren¹  Erin Burns¹  Brittni Ming‐Whitfield¹  Carrie J. Finno¹  Scott A. Katzman²  Anna M. Firshman³  Stephanie J. Valberg⁴  Amanda Borer‐Matsui⁴  Lauren Bookbinder⁴  Shelby Glessner⁴ 

[1] Department of Population Health and Reproduction University of California Davis Davis California;Department of Surgical and Radiological Sciences University of California Davis Davis California;Department of Veterinary Population Medicine, College of Veterinary Medicine University of Minnesota St Paul Minnesota;McPhail Equine Performance Center, Department of Large Animal Clinical Sciences Michigan State University East Lansing Michigan;

关键词: atrophy;    mitochondria;    myopathy;    skeletal muscle;    vitamin E;   

DOI  :  10.1111/jvim.15643

来源: DOAJ

【 摘 要 】

Abstract Background A subset of horses deficient in alpha‐tocopherol (α‐TP) develop muscle atrophy and vitamin E‐responsive myopathy (VEM) characterized by mitochondrial alterations in the sacrocaudalis dorsalis medialis muscle (SC). Objectives To quantify muscle histopathologic abnormalities in subclinical α‐TP deficient horses before and after α‐TP supplementation and compare with retrospective (r)VEM cases. Animals Prospective study; 16 healthy α‐TP‐deficient Quarter Horses. Retrospective study; 10 retrospective vitamin E‐responsive myopathy (rVEM) cases . Methods Blood, SC, and gluteus medius (GM) biopsy specimens were obtained before (day 0) and 56 days after 5000 IU/450 kg horse/day PO water dispersible liquid α‐TP (n = 8) or control (n = 8). Muscle fiber morphology and mitochondrial alterations were compared in samples from days 0 and 56 and in rVEM cases. Results Mitochondrial alterations more common than our reference range (<2.5% affected fibers) were present in 3/8 control and 4/8 treatment horses on day 0 in SC but not in GM (mean, 2.2; range, 0%‐10% of fibers). Supplementation with α‐TP for 56 days did not change the percentage of fibers with mitochondrial alterations or anguloid atrophy, or fiber size in GM or SC. Clinical rVEM horses had significantly more mitochondrial alterations (rVEM SC, 13% ± 7%; GM, 3% ± 2%) and anguloid atrophy compared to subclinical day 0 horses. Conclusions and Clinical Importance Clinically normal α‐TP‐deficient horses can have mitochondrial alterations in the SC that are less severe than in atrophied VEM cases and do not resolve after 56 days of α‐TP supplementation. Preventing α‐TP deficiency may be of long‐term importance for mitochondrial viability.

【 授权许可】

Unknown