title: Blueberry intake alters skeletal muscle and adipose tissue peroxisome proliferator-activated receptor activity and reduces insulin resistance in obese rats.
abstract: Metabolic syndrome can precede the development of type 2 diabetes and cardiovascular disease and includes phenotypes such as obesity, systemic inflammation, insulin resistance, and hyperlipidemia. A recent epidemiological study indicated that blueberry intake reduced cardiovascular mortality in humans, but the possible genetic mechanisms of this effect are unknown. Blueberries are a rich source of anthocyanins, and anthocyanins can alter the activity of peroxisome proliferator-activated receptors (PPARs), which affect energy substrate metabolism. The effect of blueberry intake was assessed in obesity-prone rats. Zucker Fatty and Zucker Lean rats were fed a higher-fat diet (45% of kcal) or a lower-fat diet (10% of kcal) containing 2% (wt/wt) freeze-dried whole highbush blueberry powder or added sugars to match macronutrient and calorie content. In Zucker Fatty rats fed a high-fat diet, the addition of blueberry reduced triglycerides, fasting insulin, homeostasis model index of insulin resistance, and glucose area under the curve. Blueberry intake also reduced abdominal fat mass, increased adipose and skeletal muscle PPAR activity, and affected PPAR transcripts involved in fat oxidation and glucose uptake/oxidation. In Zucker Fatty rats fed a low-fat diet, the addition of blueberry also significantly reduced liver weight, body weight, and total fat mass. Finally, Zucker Lean rats fed blueberry had higher body weight and reduced triglycerides, but all other measures were unaffected. In conclusion, whole blueberry intake reduced phenotypes of metabolic syndrome in obesity-prone rats and affected PPAR gene transcripts in adipose and muscle tissue involved in fat and glucose metabolism.
authors.affiliation: Cardiovascular Center and the Michigan Integrative Medicine Program, University of Michigan Health System, Ann Arbor, Michigan 48109, USA. mitchell.seymour@gmail.com
authors.forename: E Mitchell
authors.initials: EM
authors.lastname: Seymour
authors.forename: Ignasia I
authors.initials: II
authors.lastname: Tanone
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Urcuyo-Llanes
authors.forename: Sarah K
authors.initials: SK
authors.lastname: Lewis
authors.forename: Ara
authors.initials: A
authors.lastname: Kirakosyan
authors.forename: Michael G
authors.initials: MG
authors.lastname: Kondoleon
authors.forename: Peter B
authors.initials: PB
authors.lastname: Kaufman
authors.forename: Steven F
authors.initials: SF
authors.lastname: Bolling
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D000872:Anthocyanins / Q000008:administration & dosage; D029798:Blueberry Plants / Q000737:chemistry*; D018752:Diet, Fat-Restricted; D059305:Diet, High-Fat; D004041:Dietary Fats / Q000008:administration & dosage; D002149:Energy Intake; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D050356:Lipid Metabolism / Q000187:drug effects; D008297:Male; D024821:Metabolic Syndrome / Q000188:drug therapy; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000378:metabolism; D009765:Obesity / Q000188:drug therapy; D047492:Peroxisome Proliferator-Activated Receptors / Q000187:drug effects / Q000378:metabolism*; D010641:Phenotype; D010936:Plant Extracts / Q000008:administration & dosage*; D051381:Rats; D011924:Rats, Zucker; D014280:Triglycerides / Q000097:blood
chemical_list: D000872:Anthocyanins; D004041:Dietary Fats; D007328:Insulin; D047492:Peroxisome Proliferator-Activated Receptors; D010936:Plant Extracts; D014280:Triglycerides