Open AccessPreoperative overnight parenteral nutrition ( TPN ) improves skeletal muscle protein metabolism indicated by microarray algorithm analyses in a randomized trial
Author(s) -
Iresjö BrittMarie,
Engström Cecilia,
Lundholm Kent
Publication year - 2016
Publication title -
physiological reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.918
H-Index - 39
ISSN - 2051-817X
DOI - 10.14814/phy2.12789
Subject(s) - parenteral nutrition , p70 s6 kinase 1 , anabolism , skeletal muscle , medicine , protein degradation , endocrinology , protein biosynthesis , microarray , messenger rna , pi3k/akt/mtor pathway , gene expression , biology , bioinformatics , signal transduction , gene , biochemistry
Loss of muscle mass is associated with increased risk of morbidity and mortality in hospitalized patients. Uncertainties of treatment efficiency by short‐term artificial nutrition remain, specifically improvement of protein balance in skeletal muscles. In this study, algorithmic microarray analysis was applied to map cellular changes related to muscle protein metabolism in human skeletal muscle tissue during provision of overnight preoperative total parenteral nutrition ( TPN ). Twenty‐two patients (11/group) scheduled for upper GI surgery due to malignant or benign disease received a continuous peripheral all‐in‐one TPN infusion (30 kcal/kg/day, 0.16 gN /kg/day) or saline infusion for 12 h prior operation. Biopsies from the rectus abdominis muscle were taken at the start of operation for isolation of muscle RNA . RNA expression microarray analyses were performed with Agilent Sureprint G3, 8 × 60K arrays using one‐color labeling. 447 mRNA s were differently expressed between study and control patients ( P < 0.1). mRNA s related to ribosomal biogenesis, mRNA processing, and translation were upregulated during overnight nutrition; particularly anabolic signaling S6K1 ( P < 0.01–0.1). Transcripts of genes associated with lysosomal degradation showed consistently lower expression during TPN while mRNA s for ubiquitin‐mediated degradation of proteins as well as transcripts related to intracellular signaling pathways, PI 3 kinase/ MAP kinase, were either increased or decreased. In conclusion, muscle mRNA alterations during overnight standard TPN infusions at constant rate altered mRNA s associated with mTOR signaling; increased initiation of protein translation; and suppressed autophagy/lysosomal degradation of proteins. This indicates that overnight preoperative parenteral nutrition is effective to promote muscle protein metabolism.