title: Skeletal muscle gene expression profile is modified by dietary protein source and calcium during energy restriction.
abstract: OBJECTIVE
  The potential of whey protein and calcium to modify skeletal muscle gene expression during energy restriction (ER) was investigated in a model of diet-induced obesity.
  
  
  METHODS
  Obese C57BL/6J mice received casein (calcium 0.4%) and two different high-calcium (1.8%) whey protein-based [whey protein isolate (WPI)+Ca and α-lactalbumin+Ca] diets for ER.
  
  
  RESULTS
  Compared to casein, WPI and α-lactalbumin-based diets altered 208 and 287 genes, respectively, of which 186 genes were common to WPI and α-lactalbumin diets. These genes represented 31 KEGG pathways. The Wnt signaling was the most enriched pathway among the 101 genes regulated by α-lactalbumin only, whereas the 22 genes regulated by WPI only were not associated with KEGG pathways. Unlike casein, WPI and α-lactalbumin diets decreased Aldh1a7, Fasn, leptin, Nr4a3 and Scd1 mRNA expression, indicating dietary protein source-dependent alterations in muscle lipid and fatty acid metabolism. Muscle weight or lean body mass maintenance did not differ between groups although modest changes in hypertrophy/atrophy signaling were found.
  
  
  CONCLUSIONS
  The skeletal muscle gene expression profile is modified by the dietary protein source and calcium during ER which may explain, at least in part, the greater anti-obesity effect of whey proteins and calcium compared to casein.
authors.affiliation: Institute of Biomedicine, Pharmacology, University of Helsinki, Helsinki, Finland.
authors.forename: Eveliina
authors.initials: E
authors.lastname: Tauriainen
authors.forename: Markus
authors.initials: M
authors.lastname: Storvik
authors.forename: Piet
authors.initials: P
authors.lastname: Finckenberg
authors.forename: Saara
authors.initials: S
authors.lastname: Merasto
authors.forename: Essi
authors.initials: E
authors.lastname: Martonen
authors.forename: Taru K
authors.initials: TK
authors.lastname: Pilvi
authors.forename: Riitta
authors.initials: R
authors.lastname: Korpela
authors.forename: Eero M
authors.initials: EM
authors.lastname: Mervaala
mesh_terms: D000465:Algorithms; D000818:Animals; D001823:Body Composition / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D002136:Calcium, Dietary / Q000494:pharmacology*; D031204:Caloric Restriction; D002364:Caseins / Q000494:pharmacology; D016000:Cluster Analysis; D004044:Dietary Proteins / Q000494:pharmacology*; D002149:Energy Intake / Q000235:genetics / Q000502:physiology; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D046228:Microarray Analysis; D008894:Milk Proteins / Q000494:pharmacology; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000378:metabolism*; D000067816:Whey Proteins
chemical_list: D002136:Calcium, Dietary; D002364:Caseins; D004044:Dietary Proteins; D008894:Milk Proteins; D000067816:Whey Proteins