title: Chronic dietary exposure to branched chain amino acids impairs glucose disposal in vegans but not in omnivores.
abstract: Branched chain amino acids (BCAA) are among nutrients strongly linked with insulin sensitivity (IS) measures. We investigated the effects of a chronic increase of BCAA intake on IS in two groups of healthy subjects differing in their basal consumption of BCAA, that is, vegans and omnivores.
  
  
  
  Eight vegans and eight matched omnivores (five men and three women in each group) received 15 g (women) or 20 g (men) of BCAA daily for 3 months. Anthropometry, blood analyses, glucose clamp, arginine test, subcutaneous abdominal adipose tissue (AT) and skeletal muscle (SM) biopsies (mRNA levels of selected metabolic markers, respiratory chain (RC) activity) were performed at baseline, after the intervention and after a 6 month wash-out period.
  
  
  
  Compared with omnivores, vegans had higher IS at baseline (GIR, glucose infusion rate: 9.6±2.4 vs 7.1±2.4 mg/kg/min, 95% CI for difference: 0.55 to 5.82) that declined after the intervention and returned to baseline values after the wash-out period (changes in GIR with 95% CI, 3-0 months: -1.64 [-2.5; -0.75] and 9-3 months: 1.65 [0.75; 2.54] mg/kg/min). No such change was observed in omnivores. In omnivores the intervention led to an increased expression of lipogenic genes (DGAT2, FASN, PPARγ, SCD1) in AT. SM RC activity increased in both groups.
  
  
  
  Negative impact of increased BCAA intake on IS was only detected in vegans, that is, subjects with low basal amino acids/BCAA intake, which appear to be unable to induce sufficient compensatory changes within AT and SM on a BCAA challenge.
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.|Division of Clinical Physiology, 2nd Department of Internal Medicine University Hospital Královské Vinohrady, Šrobárova 50, Prague 10 100 34, Czech Republic Prague.
authors.forename: J
authors.initials: J
authors.lastname: Gojda
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.|Department of Sport Medicine, Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.
authors.forename: L
authors.initials: L
authors.lastname: Rossmeislová
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.|Division of Clinical Physiology, 2nd Department of Internal Medicine University Hospital Královské Vinohrady, Šrobárova 50, Prague 10 100 34, Czech Republic Prague.
authors.forename: R
authors.initials: R
authors.lastname: Straková
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.
authors.forename: J
authors.initials: J
authors.lastname: Tůmová
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.
authors.forename: M
authors.initials: M
authors.lastname: Elkalaf
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.
authors.forename: M
authors.initials: M
authors.lastname: Jaček
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.
authors.forename: P
authors.initials: P
authors.lastname: Tůma
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.|Division of Clinical Physiology, 2nd Department of Internal Medicine University Hospital Královské Vinohrady, Šrobárova 50, Prague 10 100 34, Czech Republic Prague.
authors.forename: J
authors.initials: J
authors.lastname: Potočková
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.|Division of Clinical Physiology, 2nd Department of Internal Medicine University Hospital Královské Vinohrady, Šrobárova 50, Prague 10 100 34, Czech Republic Prague.|Department of Sport Medicine, Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.
authors.forename: E
authors.initials: E
authors.lastname: Krauzová
authors.affiliation: Department of Anaesthesia and Intensive Care Medicine, University Hospital Královské Vinohrady and Third Faculty of Medicine, Charles University, Šrobárova 50, Prague 10 100 34, Czech Republic Prague.
authors.forename: P
authors.initials: P
authors.lastname: Waldauf
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.
authors.forename: J
authors.initials: J
authors.lastname: Trnka
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.|Division of Clinical Physiology, 2nd Department of Internal Medicine University Hospital Královské Vinohrady, Šrobárova 50, Prague 10 100 34, Czech Republic Prague.|Department of Sport Medicine, Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.
authors.forename: V
authors.initials: V
authors.lastname: Štich
authors.affiliation: Centre for Research on Diabetes, Metabolism and Nutrition of Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.|Department of Sport Medicine, Third Faculty of Medicine, Charles University in Prague, Ruská 87, Prague 10 100 00 Czech Republic.
authors.forename: M
authors.initials: M
authors.lastname: Anděl
mesh_terms: D000328:Adult; D000597:Amino Acids, Branched-Chain / Q000008:administration & dosage* / Q000097:blood; D000886:Anthropometry; D001786:Blood Glucose / Q000378:metabolism*; D004032:Diet; D000067269:Diet, Vegan; D000074341:Dietary Exposure / Q000009:adverse effects*; D004044:Dietary Proteins / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D015444:Exercise; D005260:Female; D015309:Glucose Clamp Technique; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D000066989:Vegans; D055815:Young Adult
chemical_list: D000597:Amino Acids, Branched-Chain; D001786:Blood Glucose; D004044:Dietary Proteins; D007328:Insulin