title: Altering dietary lysine:arginine ratio has little effect on cardiovascular risk factors and vascular reactivity in moderately hypercholesterolemic adults.
abstract: BACKGROUND
  Information is scarce regarding the effect of dietary protein type, with specific focus on the lysine-to-arginine (Lys:Arg) ratio, on cardiovascular risk factors and vascular reactivity in humans.
  
  
  OBJECTIVE
  Determine the effect of dietary Lys:Arg ratio on cardiovascular risk factors and vascular reactivity in moderately hypercholesterolemic adults.
  
  
  METHODS
  Randomized cross-over design of two 35-day diet phases; thirty adults (21 females and 9 males, >or=50 years, LDL cholesterol>or=120 mg/dL). Diets had 20% energy (E) protein, 30%E fat, 50%E carbohydrate and were designed to have low (0.7) or high (1.4) Lys:Arg ratio. Measures included fasting and postprandial lipid, lipoprotein, apolipoprotein concentrations; fasting high sensitivity C-reactive protein (hsCRP), small dense LDL (sdLDL) cholesterol, remnant lipoprotein cholesterol (RemLC), glycated albumin, adiponectin and immunoreactive insulin concentrations, endogenous cholesteryl ester transfer protein (CETP) and lecithin:cholesterol acyl transferase (LCAT) activities; cholesterol fractional synthesis rate (FSR); and flow mediated dilation (FMD) and peripheral artery tonometry (PAT).
  
  
  RESULTS
  No differences were observed in fasting and/or postprandial total, LDL, HDL and sdLDL cholesterol, RemLC, Lp(a) or apo B concentrations, LCAT and CETP activities, FSR, glycated albumin, immunoreactive insulin, FMD or PAT. The low, relative to the high, Lys:Arg ratio diet resulted in lower postprandial VLDL cholesterol (-24%, P=0.001) and triglycerides (-23%, P=0.001), and small but significant differences in fasting (-3%, P=0.003) and postprandial (-3%, P=0.018) apo AI, and fasting adiponectin concentrations (+7%, P=0.035). Fasting and postprandial hsCRP concentrations were 23% lower after the low Lys:Arg ratio diet (P=0.020 for both).
  
  
  CONCLUSIONS
  Diets differing in Lys:Arg ratios had no or small effects on cardiovascular risk factors and vascular reactivity.
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA.
authors.forename: Sonia
authors.initials: S
authors.lastname: Vega-López
authors.forename: Nirupa R
authors.initials: NR
authors.lastname: Matthan
authors.forename: Lynne M
authors.initials: LM
authors.lastname: Ausman
authors.forename: Scott V
authors.initials: SV
authors.lastname: Harding
authors.forename: Todd C
authors.initials: TC
authors.lastname: Rideout
authors.forename: Masumi
authors.initials: M
authors.lastname: Ai
authors.forename: Seiko
authors.initials: S
authors.lastname: Otokozawa
authors.forename: Alicia
authors.initials: A
authors.lastname: Freed
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Kuvin
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Jones
authors.forename: Ernst J
authors.initials: EJ
authors.lastname: Schaefer
authors.forename: Alice H
authors.initials: AH
authors.lastname: Lichtenstein
mesh_terms: D052242:Adiponectin / Q000378:metabolism; D000368:Aged; D001120:Arginine / Q000378:metabolism*; D001808:Blood Vessels / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000517:prevention & control*; D002784:Cholesterol / Q000378:metabolism; D018592:Cross-Over Studies; D004032:Diet; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000178:diet therapy*; D008239:Lysine / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000378:metabolism; D012307:Risk Factors
chemical_list: D052242:Adiponectin; D001120:Arginine; D002784:Cholesterol; D007862:Phosphatidylcholine-Sterol O-Acyltransferase; D008239:Lysine