Salivary composition in obese vs normal-weight subjects: towards a role in postprandial lipid metabolism?
In the pathophysiological context of obesity, oral exposure to dietary fat can modulate lipid digestion and absorption, but underlying in-mouth mechanisms have not been clearly identified. Therefore, we tested the hypothesis that salivary components related to dietary fat sensitivity would differ according to body mass index (BMI) and postprandial lipid metabolism in young men. Saliva was collected from nine normal-weight (BMI=22.3±0.5 kg m(-2)) and nine non-morbid obese (BMI=31.7±0.3 kg m(-2)) men before an 8-h postprandial metabolic exploration test involving the consumption of a 40-g fat meal, in which obese subjects revealed a delayed postprandial lipid metabolism. Nine salivary characteristics (flow, protein content, lipolysis, amylase, proteolysis, total antioxidant status, lysozyme, lipocalin 1 and carbonic anhydrase-VI) were investigated. We show that, under fasting conditions, salivary lipolysis was lower in obese vs normal-weight subjects, whereas proteolysis and carbonic anhydrase VI were higher. We reveal through multivariate and Mann-Whitney analysis that differences in fasting salivary lipolysis and proteolysis between both groups are related to differences in postprandial lipid metabolism including exogenous fatty-acid absorption and β-oxidation. These results suggest a potential role of salivary composition on postprandial lipid metabolism and bring novel causal hypotheses on the links between salivary composition, sensitivity to dietary fat oral income and postprandial lipid metabolism according to BMI.
INRA, UMR 1397, CarMeN Laboratory, Univ Lyon-1, Oullins, France.|INSERM U1060, CarMeN Laboratory, Oullins, France.|Centre de Recherche en Nutrition Humaine Rhône-Alpes (CRNH-RA) and Centre Européen pour la Nutrition et la Santé (CENS), Pierre-Bénite, France.
C
C
Vors
Laboratoire de Biochimie, Centre Hospitalier Lyon Sud, Pierre-Bénite, France.
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J
Drai
INRA, UMR 1397, CarMeN Laboratory, Univ Lyon-1, Oullins, France.|Centre de Recherche en Nutrition Humaine Rhône-Alpes (CRNH-RA) and Centre Européen pour la Nutrition et la Santé (CENS), Pierre-Bénite, France.
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L
Gabert
INRA, UMR 1397, CarMeN Laboratory, Villeurbanne, France.|INSA-Lyon, IMBL, Villeurbanne, France.
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Pineau
INRA, UMR 1397, CarMeN Laboratory, Univ Lyon-1, Oullins, France.|Centre de Recherche en Nutrition Humaine Rhône-Alpes (CRNH-RA) and Centre Européen pour la Nutrition et la Santé (CENS), Pierre-Bénite, France.
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Laville
INRA, UMR 1397, CarMeN Laboratory, Univ Lyon-1, Oullins, France.|INSERM U1060, CarMeN Laboratory, Oullins, France.
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H
Vidal
CNRS, UMR6265 Centre des Sciences du Goût et de l'Alimentation, Dijon, France.|INRA, UMR1324 Centre des Sciences du Goût et de l'Alimentation, Dijon, France.|Université de Bourgogne, UMR Centre des Sciences du Goût et de l'Alimentation, Dijon, France.
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Guichard
INRA, UMR 1397, CarMeN Laboratory, Univ Lyon-1, Oullins, France.|INRA, UMR 1397, CarMeN Laboratory, Villeurbanne, France.|INSA-Lyon, IMBL, Villeurbanne, France.|Centre de Recherche en Nutrition Humaine Rhône-Alpes (CRNH-RA) and Centre Européen pour la Nutrition et la Santé (CENS), Pierre-Bénite, France.
M-C
MC
Michalski
CNRS, UMR6265 Centre des Sciences du Goût et de l'Alimentation, Dijon, France.|INRA, UMR1324 Centre des Sciences du Goût et de l'Alimentation, Dijon, France.|Université de Bourgogne, UMR Centre des Sciences du Goût et de l'Alimentation, Dijon, France.
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Feron
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D004041:Dietary Fats; D004734:Energy Metabolism; D006801:Humans; D050356:Lipid Metabolism; D008066:Lipolysis; D008297:Male; D062407:Meals; D009765:Obesity / Q000378:metabolism* / Q000503:physiopathology; D019518:Postprandial Period; D012463:Saliva / Q000737:chemistry* / Q000378:metabolism; D013851:Thinness / Q000378:metabolism* / Q000503:physiopathology
D001786:Blood Glucose; D004041:Dietary Fats