Fish oil mitigates myosteatosis and improves chemotherapy efficacy in a preclinical model of colon cancer

• Published in: PloS one 2017-08, Vol.12 (8), p.e0183576-e0183576
• Main Authors: Almasud, Alaa A, Giles, Kaitlin H, Miklavcic, John J, Martins, Karen J B, Baracos, Vickie E, Putman, Charles T, Guan, Leluo L, Mazurak, Vera C
• Format: Article
• Language: English
• Subjects: 5-Fluorouracil; Adipocytes; Adipogenesis; Adipose Tissue - metabolism; Animals; Antineoplastic Agents - adverse effects; Antineoplastic Agents - therapeutic use; Biology and Life Sciences; Cancer therapies; Chemotherapy; Colon; Colon cancer; Colonic Neoplasms - drug therapy; Colorectal cancer; Diet; Disease Models, Animal; Drug Synergism; Effectiveness; Fatty acids; Feeding; Feeding Behavior; Female; Fish; Fish oils; Fish Oils - pharmacology; Fish Oils - therapeutic use; Food; Gas chromatography; Gene expression; Implantation; Irinotecan; Lipids; Lipogenesis; Lung cancer; Medicine and Health Sciences; Metabolism; Muscle, Skeletal - drug effects; Muscle, Skeletal - metabolism; Muscle, Skeletal - pathology; Musculoskeletal system; Nutrition; Oils & fats; Oncology; Polymerase chain reaction; Rats; Rats, Inbred F344; Real-Time Polymerase Chain Reaction; Rodents; Skeletal muscle; Staining; Studies; Transcription factors; Transcription Factors - metabolism
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0183576

This study aimed to assess whether feeding a diet containing fish oil was efficacious in reducing tumor- and subsequent chemotherapy-associated myosteatosis, and improving tumor response to treatment. Female Fischer 344 rats were fed either a control diet for the entire study (control), or switched to a diet containing fish oil (2.0 g /100 g of diet) one week prior to tumor implantation (long term fish oil) or at the start of chemotherapy (adjuvant fish oil). Chemotherapy (irinotecan plus 5-fluorouracil) was initiated 2 weeks after tumor implantation (cycle-1) and 1 week thereafter (cycle-2). Reference animals received no tumor or treatment and only consumed the control diet. All skeletal muscle measures were conducted in the gastrocnemius. To assess myosteatosis, lipids were assessed histologically by Oil Red O staining and total triglyceride content was quantified by gas chromatography. Expression of adipogenic transcription factors were assessed at the mRNA level by real-time RT-PCR. Feeding a diet containing fish oil significantly reduced tumor- and subsequent chemotherapy-associated increases in skeletal muscle neutral lipid (p