title: The protein source determines the potential of high protein diets to attenuate obesity development in C57BL/6J mice.
abstract: The notion that the obesogenic potential of high fat diets in rodents is attenuated when the protein:carbohydrate ratio is increased is largely based on studies using casein or whey as the protein source. We fed C57BL/6J mice high fat-high protein diets using casein, soy, cod, beef, chicken or pork as protein sources. Casein stood out as the most efficient in preventing weight gain and accretion of adipose mass. By contrast, mice fed diets based on pork or chicken, and to a lesser extent mice fed cod or beef protein, had increased adipose tissue mass gain relative to casein fed mice. Decreasing the protein:carbohydrate ratio in diets with casein or pork as protein sources led to accentuated fat mass accumulation. Pork fed mice were more obese than casein fed mice, and relative to casein, the pork-based feed induced substantial accumulation of fat in classic interscapular brown adipose tissue accompanied by decreased UCP1 expression. Furthermore, intake of a low fat diet with casein, but not pork, as a protein source reversed diet-induced obesity. Compared to pork, casein seems unique in maintaining the classical brown morphology in interscapular brown adipose tissue with high UCP1 expression. This was accompanied by increased expression of genes involved in a futile cycling of fatty acids. Our results demonstrate that intake of high protein diets based on other protein sources may not have similar effects, and hence, the obesity protective effect of high protein diets is clearly modulated by protein source.
authors.affiliation: National Institute of Nutrition and Seafood Research, Bergen, Norway; Department of Biology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Liisberg
authors.affiliation: National Institute of Nutrition and Seafood Research, Bergen, Norway; Department of Biology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Lene Secher
authors.initials: LS
authors.lastname: Myrmel
authors.affiliation: National Institute of Nutrition and Seafood Research, Bergen, Norway; Department of Biology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Even
authors.initials: E
authors.lastname: Fjære
authors.affiliation: National Institute of Nutrition and Seafood Research, Bergen, Norway; Department of Biology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Alexander K
authors.initials: AK
authors.lastname: Rønnevik
authors.affiliation: National Institute of Nutrition and Seafood Research , Bergen, Norway.
authors.forename: Susanne
authors.initials: S
authors.lastname: Bjelland
authors.affiliation: National Institute of Nutrition and Seafood Research , Bergen, Norway.
authors.forename: Kristin Røen
authors.initials: KR
authors.lastname: Fauske
authors.affiliation: Department of Biology, University of Copenhagen , Copenhagen, Denmark.
authors.forename: Jacob Bak
authors.initials: JB
authors.lastname: Holm
authors.affiliation: Department of Biology, University of Copenhagen , Copenhagen, Denmark.
authors.forename: Astrid Linde
authors.initials: AL
authors.lastname: Basse
authors.affiliation: Department of Biology, University of Copenhagen , Copenhagen, Denmark.
authors.forename: Jacob B
authors.initials: JB
authors.lastname: Hansen
authors.affiliation: National Institute of Nutrition and Seafood Research , Bergen, Norway.
authors.forename: Bjørn
authors.initials: B
authors.lastname: Liaset
authors.affiliation: Department of Biology, University of Copenhagen , Copenhagen, Denmark.
authors.forename: Karsten
authors.initials: K
authors.lastname: Kristiansen
authors.affiliation: National Institute of Nutrition and Seafood Research, Bergen, Norway; Department of Biology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Lise
authors.initials: L
authors.lastname: Madsen
keywords: adiposity; animal models; brown adipose tissue; diet; protein sources