36 research outputs found
Fasting and refeeding impacts on piglet jejunal transcriptome during weaning period
International audienc
Diet-induced obesity in young mice interferes with the pancreatic intrinsic nervous system maturation and alters its control of insulin secretion
Pancreatic Intrinsic Nervous System (PINS) maturation goes on postnatally and is involved in the control of pulsatility and amplitude of insulin secretion (IS), both altered in obese and diabetic patients. The aim of our study was to determine the impact of obesity in infancy on PINS maturation and control of IS.C57BL/6J mice aged 4 weeks received a normal (ND) or a western diet (WD) for 12 weeks. 4 weeks old mice were used as initial controls (T0). After sacrifice, pancreases were placed in organ incubators for 1 h. The impact of PINS upon IS was studied by adding to the culture the nicotinic receptors agonist DMPP in presence or absence of L-NAME (inhibitor of NOS) or SNP (NO donor). Insulin was assayed in culture supernatants. PINS density and phenotype were determined by IHC.PINS density was less in ND compared to T0 mice, whereas there was no difference between WD and T0 mice. Cholinergic innervation significantly increased with age in both WD and ND mice whereas nitrergic innervation increased in ND mice and decreased in WD.PINS stimulation by DMPP induced a time-dependent increase in IS, significantly larger in ND compared to WD mice. IS profile was identical in WD and T0 mice. Addition of L-Name inhibited DMPP-induced IS in ND mice while SNP tended to reduce it. Neither L-Name nor SNP altered IS in WD mice.Our study suggests that WD induces neuroplastic changes in the PINS that could be involved in pancreatic dysfunctions observed during obesity
Diet-induced obesity in young mice: consequences on the pancreatic intrinsic nervous system control of insulin secretion
International audienceINTRODUCTION: Obesity has become a pandaemic even in children. We aimed to investigate the impact of obesity in youth on later pancreatic intrinsic nervous system (PINS) phenotype and control of insulin secretion.METHODS: Young mice (5-week-old, T0 group) were fed either a normal diet (ND group) or a Western diet (WD group) for 12Â weeks. Pancreas nervous system density, PINS phenotype and pancreas anatomy were analysed by immunohistochemistry at T0 and in adulthood (ND and WD groups). Insulin secretion was also studied in these 3 groups using a new model of ex vivo pancreatic culture, where PINS was stimulated by nicotinic and nitrergic agonists with and without antagonists. Insulin was assayed in supernatants by ELISA.RESULTS: Pancreas nervous system density decreased with age in ND (PÂ <Â .01) but not in WD mice (PÂ =Â .08). Western diet decreased the PINS nitrergic component as compared to normal diet (PÂ <Â .01) but it did not modify its cholinergic component (PÂ =Â .50). Nicotinic PINS stimulation induced greater insulin secretion in ND compared to WD mice (PÂ <Â .001) whereas nitrergic stimulation significantly decreased insulin secretion in ND mice (PÂ <Â .001) and tended to increase insulin secretion in WD mice (PÂ =Â .08). Endocrine pancreas anatomy was not modified by the Western diet as compared to the normal diet (PÂ =Â .93).CONCLUSIONS: Early Western diet induced neuronal density and phenotype changes in PINS that might be involved in the pancreas insulin secretion dysfunctions associated with obesity
DĂ©veloppement post-natal du systĂšme ghrĂ©line et impact dâune formule infantile enrichie en acides gras Ă chaine moyenne chez le mini-porc Yucatan.
International audienc
Post-natal development of the ghrelin system and impact of medium-chain fatty acid-enriched formula feeding in Yucatan mini-pigs
International audienc
Impact de lâalimentation maternelle enrichie en fibres prĂ©biotiques sur les rĂ©ponses mĂ©taboliques et immunitaires de la descendance Ă un rĂ©gime hyperlipidique
Impact de lâalimentation maternelle enrichie en fibres prĂ©biotiques sur les rĂ©ponses mĂ©taboliques et immunitaires de la descendance Ă un rĂ©gime hyperlipidique. JournĂ©e maladies neuro-digestives et mĂ©tabolique
QualitĂ© nutritionnelle des protĂ©ines du lait humain et dâune prĂ©paration pour nourrissons, Ă©tude prĂ©-clinique chez le modĂšle mini-porcelet
International audienceIntroduction et but de lâĂ©tudeLa formulation des prĂ©parations pour nourrissons (PPN) est trĂšs rĂ©glementĂ©e et doit mimer au mieux lâaminogramme du lait humain (LH), premier Ă©lĂ©ment essentiel de la qualitĂ© nutritionnelle des protĂ©ines. Peu dâĂ©tudes in vivo se sont intĂ©ressĂ©es Ă la digestibilitĂ© des acides aminĂ©s (AA) du LH et des PPNs, permettant dâestimer leur biodisponibilitĂ©, autre indicateur important de la qualitĂ© nutritionnelle des protĂ©ines. Lâobjectif de cette Ă©tude Ă©tait de mesurer la digestibilitĂ© ilĂ©ale vraie (DIV) des protĂ©ines du LH et dâune PPN, afin de calculer leur DIAAS (Digestible Indispensable Amino Acid Score ; FAO, 2013). Un modĂšle mini-porcelet a Ă©tĂ© utilisĂ© comme modĂšle du nourrisson.MatĂ©riel et MĂ©thodesDes porcelets ĂągĂ©s de 19 jours ont reçu pendant 6 jours du LH (n=7) ou une PPN (n=9). Un troisiĂšme groupe de porcelets a reçu un rĂ©gime sans protĂ©ines (n=6), permettant dâĂ©valuer les pertes en protĂ©ines endogĂšnes. Les trois rĂ©gimes contenaient du Cobalt-EDTA comme marqueur de transit. Le dernier jour, les repas ont Ă©tĂ© distribuĂ©s toutes les heures pendant six heures avant sacrifice des animaux et rĂ©cupĂ©ration des contenus ilĂ©aux pour mesurer la digestibilitĂ© vraie de lâazote total et des AA. Le DIAAS a Ă©tĂ© calculĂ© Ă partir des digestibilitĂ©s et des teneurs en AA des aliments au regard du profil de rĂ©fĂ©rence, correspondant au profil en AA du LH (FAO, 2007). Des hydrolyses de durĂ©es multiples (0 Ă 120 h) des Ă©chantillons ont Ă©tĂ© rĂ©alisĂ©es afin dâĂ©valuer les pertes en AA au cours de cette Ă©tape et corriger les valeurs classiquement obtenues Ă 24 h dâhydrolyse acide ou 16 h dâhydrolyse basique pour le tryptophane. Une ANOVA multifactorielle a permis lâanalyse et la comparaison des donnĂ©es.RĂ©sultats et Analyses statistiquesLes hydrolyses multiples ont permis de corriger les teneurs en AA des aliments et des digestas, en particulier pour la tyrosine et la valine (+10% de la valeur mesurĂ©e Ă 24 h dâhydrolyse). Les profils en AA du LH Ă©taient en accord avec la mĂ©ta-analyse de Zhang et al. (2003). La DIV de lâazote aminĂ© nâĂ©tait pas significativement diffĂ©rente (LM : 96,7 ± 1,0 % et PPN : 98,0 ± 0,7 for IF, p > 0,05) tandis que la DIV de lâazote total Ă©tait significativement plus faible pour le LH (91,3 ± 1,2 %) que pour la PPN (98,0 ± 0,9 %). Cette diffĂ©rence sâexpliquait par la plus forte proportion dâazote non protĂ©ique dans le LH (LH : 31,0 ± 0,7 % et PPN :4,4 ± 0,2 % de lâazote total), partiellement non digestible et non-absorbable. Quelques AA prĂ©sentaient des diffĂ©rences de digestibilitĂ©. Ainsi, la lysine Ă©tait significativement plus digestible dans le LH que dans la PPN (98,4 ± 0,7 % vs. 96,0 ± 0,5 %), probablement liĂ© Ă lâabsence de glycation des protĂ©ines (rĂ©action de Maillard) dans le LH. A lâinverse, les DIVs de la phĂ©nylalanine, la thrĂ©onine, la valine, lâalanine, la proline et la sĂ©rine, Ă©taient significativement lĂ©gĂšrement plus faibles dans le LH que dans la PPN (-2,6 Ă -7,3 points). La DIV moyenne dutryptophane Ă©tait proche entre le LH et la PPN (96,8 ± 0,5 %, p = 0,079). Le DIAAS Ă©tait plus Ă©levĂ© pour le LH que pour la PPN (+10%) et Ă©tait, pour les deux aliments, liĂ©s Ă une teneur en AA aromatiques (phĂ©nylalanine + tyrosine) plus basse que celle du profil de rĂ©fĂ©rence.ConclusionCette Ă©tude a dĂ©montrĂ© que le LH, comparĂ© Ă la PPN, avait une DIV plus faible uniquement pour lâazote total et non pas pour lâazote aminĂ©. Ceci suggĂšre quâune fraction dâazote non protĂ©ique du LH est sous forme non digestible et non absorbable, tel que lâurĂ©e, et est donc transfĂ©rĂ©e vers le colon. Cette fraction azotĂ©e, bien que peu considĂ©rĂ©e dans la formulation des PPNs, peut cependant avoir un rĂŽle sur la composition du microbiote. Par ailleurs, la digestibilitĂ© plus Ă©levĂ©e de la lysine dans le LH que la PPN, est certainement dĂ» Ă lâabsence de rĂ©action de Maillard dans le LH contrairement aux PPNs, qui reçoivent de nombreux traitements thermique
Casein structure differently impacts satiety by modulating plasma aminoacid kinetic
International audienceDietary protein is strong appetite inhibitor as it reduces food intake in following meals by signalingdirectly or indirectly to the brain, modulating eating behavior. However, the type of protein in snacksor pre-loads differently influences food intake, likely due to differences in dietary protein hydrolysisand amino acid bioavailability. We recently observed striking differences in plasma amino acidkinetics as well as intra-gastric behavior between micellar casein (MC) and sodium caseinate (SC).Gastric distension and plasma amino acid levels, in particular that of leucine, both impact foodintake. The objective of the present study was therefore to clarify whether the structure of caseinimpacts its preload effect on subsequent food intake in the pig model.Overnight fasted pigs (21.5 ± 1.5 kg) equipped with jugular catheters were allowed to consumewithin 5 min casein drinks differing in casein structure (SC vs. MC, 350 kcal, 10% casein, 1.2% glucosein water) in a cross-over study. Ad libitum intake of their regular feed was assessed during 1hr, either1 or 4hr after casein drink ingestion. Gastric emptying of the casein drinks radiolabeled with 99Tc-colloĂŻd was followed during 2hr using gamma-scintigraphy. Plasma kinetics of hormones related toeating behavior (ghrelin, GLP-1, insulin) and of free amino acids were evaluated for 2hr followingcasein drink ingestion.The amount of feed consumed 1hr, but not 4hr, after SC ingestion was lower than the amount offeed consumed after MC ingestion (feed consumed at 1h: SC 1306 ± 138 vs. MC 1513 ± 79 g, P=0.03).Gastric emptying parameters after both types of casein ingestion were not significantly different(t1/2: SC 103 ± 12 vs. MC 116 ± 18 min, ÎČ: SC 0.67 ± 0.14 vs. MC 0.52 ± 0.04, P>0.05). Plasma ghrelin,GLP-1 and insulin kinetics were similar after casein drink ingestion (SC vs. MC, P>0.05 for allhormones). Free plasma amino acid concentrations, in particular that of leucine, increased after bothSC and MC ingestion but was greater after SC than MC ingestion from 60 to 120 min (plasma leucineat 60 min: SC 87.8 ± 4.8 vs. MC 66.0 ± 3.5 mg/L, P=0.009).In conclusion, ingestion of casein differing in their structure impacts subsequent food intake likelydue to difference in amino acid bioavailability. Casein exhibits less anorectic effect when consumedas micellar casein than as sodium caseinate. Such differences might be of importance when designingfood dedicated to people with low appetite
Un régime hyperlipidique entraßne des désordres métaboliques sans modification de la composition corporellechez le porc conventionnel adulte
Un régime hyperlipidique entraßne des désordres métaboliques sans modification de la composition corporellechez le porc conventionnel adulte. 12. Journées Francophones de Nutrition (JFN
The ghrelin system follows a precise post-natal development in mini-pigs that is not impacted by dietary medium chain fatty-acids
International audienceThe ghrelin-ghrelin receptor (GHSR1) system is one of the most important mechanisms regulating food intake and energy balance. To be fully active, ghrelin is acylated with medium-chain fatty acids (MCFA) through the ghrelin-O-acetyl transferase (GOAT). Several studies reported an impact of dietary MCFA on ghrelin acylation in adults. Our study aimed at describing early post-natal development of the ghrelin system in mini-pigs as a model of human neonates and evaluating the impact of dietary MCFA. Suckled mini-pigs were sacrificed at post-natal day (PND) 0, 2, 5, and 10 or at adult stage. In parallel, other mini-pigs were fed from birth to PND10 a standard or a dairy lipid-enriched formula with increased MCFA concentration (DL-IF). Plasma ghrelin transiently peaked at PND2, with no variation of the acylated fraction except in adults where it was greater than during the neonatal period. Levels of mRNA coding pre-proghrelin (GHRL) and GOAT in the antrum did not vary during the post-natal period but dropped in adults. Levels of antral pcsk1/3 (cleaving GHRL into ghrelin) mRNA decreased significantly with age and was negatively correlated with plasma acylated, but not total, ghrelin. Hypothalamic ghsr1 mRNA did not vary in neonates but increased in adults. The DL-IF formula enriched antral tissue with MCFA but did not impact the ghrelin system. In conclusion, the ghrelin maturation enzyme PCSK1/3 gene expression exhibited post-natal modifications parallel to transient variations in circulating plasma ghrelin level in suckling piglets but dietary MCFA did not impact this post-natal development