title: Maillard reaction products modulate gut microbiota composition in adolescents.
abstract: METHODS
  Scarce data are available concerning effects of certain bioactive substances such as Maillard reaction products (MRP) on the gut microbiota composition, and the question of how a diet rich in MRP affects gut microbiota in humans is still open.
  
  
  RESULTS
  Two experiments were conducted. In expt. 1, adolescents consumed diets either high or low in MRP in a two-period crossover trial; in expt. 2, rats were fed diets supplemented or not with MRP model-systems. Intestinal microbiota composition in fecal (adolescents) or cecal (rat) samples was assessed by qPCR analysis. Negative correlations were found in the human assay between lactobacilli numbers and dietary advanced MRP (r = -0.418 and -0.387, for hydroxymethylfurfural and carboxymethyl-lysine respectively, p < 0.05), whereas bifidobacteria counts were negatively correlated with Amadori compounds intake. In the rat assay, total bacteria and lactobacilli were negatively correlated with MRP intake (r = -0.674,-0.675 and -0.676, for Amadori compounds, hydroxymethylfurfural and carboxymethyl-lysine respectively, p < 0.05), but no correlations were found with bifidobacteria.
  
  
  CONCLUSIONS
  Dietary MRP are able to modulate in vivo the intestinal microbiota composition both in humans and in rats, and the specific effects are likely to be linked to the chemical structure and dietary amounts of the different browning compounds.
authors.affiliation: Departamento de Fisiología y Bioquímica de la Nutrición Animal (INAN), Estación Experimental del Zaidín (CSIC), Armilla, Granada, Spain.
authors.forename: Isabel
authors.initials: I
authors.lastname: Seiquer
authors.forename: Luis A
authors.initials: LA
authors.lastname: Rubio
authors.forename: M Jesús
authors.initials: MJ
authors.lastname: Peinado
authors.forename: Cristina
authors.initials: C
authors.lastname: Delgado-Andrade
authors.forename: María Pilar
authors.initials: MP
authors.lastname: Navarro
mesh_terms: D000293:Adolescent; D000818:Animals; D001439:Bacteroides / Q000302:isolation & purification; D001644:Bifidobacterium / Q000302:isolation & purification; D002432:Cecum / Q000737:chemistry / Q000382:microbiology; D018592:Cross-Over Studies; D004032:Diet; D004755:Enterobacteriaceae / Q000302:isolation & purification; D004926:Escherichia coli / Q000302:isolation & purification; D005243:Feces / Q000737:chemistry / Q000382:microbiology; D005662:Furaldehyde / Q000031:analogs & derivatives / Q000378:metabolism; D006801:Humans; D007422:Intestines / Q000382:microbiology*; D007778:Lactobacillus / Q000302:isolation & purification; D008239:Lysine / Q000031:analogs & derivatives / Q000378:metabolism; D015416:Maillard Reaction; D008297:Male; D064307:Microbiota; D051381:Rats; D017208:Rats, Wistar; D012760:Shigella / Q000302:isolation & purification
chemical_list: C008046:5-hydroxymethylfurfural; C048496:N(6)-carboxymethyllysine; D005662:Furaldehyde; D008239:Lysine
keywords: Adolescents; Cecum; Feces; Maillard reaction products; Microbiota; Rat