Accelerated Growth Rate Induced by Neonatal High-Protein Milk Formula Is Not Supported by Increased Tissue Protein Synthesis in Low-Birth-Weight Piglets

Low-birth-weight neonates are routinely fed a high-protein formula to promote catch-up growth and antibiotics are usually associated to prevent infection. Yet the effects of such practices on tissue protein metabolism are unknown. Baby pigs were fed from age 2 to 7 or 28 d with high protein formula with or without amoxicillin supplementation, in parallel with normal protein formula, to determine tissue protein metabolism modifications. Feeding high protein formula increased growth rate between 2 and 28 days of age when antibiotic was administered early in the first week of life. This could be explained by the occurrence of diarrhea when piglets were fed the high protein formula alone. Higher growth rate was associated with higher feed conversion and reduced protein synthesis rate in the small intestine, muscle and carcass, whereas proteolytic enzyme activities measured in these tissues were unchanged. In conclusion, accelerated growth rate caused by high protein formula and antibiotics was not supported by increased protein synthesis in muscle and carcass

The Level of Protein in Milk Formula Modifies Ileal Sensitivity to LPS Later in Life in a Piglet Model

Background: Milk formulas have higher protein contents than human milk. This high protein level could modify the development of intestinal microbiota, epithelial barrier and immune functions and have long-term consequences. Methodology/Principal findings: We investigated the effect of a high protein formula on ileal microbiota and physiology during the neonatal period and later in life. Piglets were fed from 2 to 28 days of age either a normoprotein (NP, equivalent to sow milk) or a high protein formula (HP, +40% protein). Then, they received the same solid diet until 160 days. During the formula feeding period ileal microbiota implantation was accelerated in HP piglets with greater concentrations of ileal bacteria at d7 in HP than NP piglets. Epithelial barrier function was altered with a higher permeability to small and large probes in Ussing chambers in HP compared to NP piglets without difference in bacterial translocation. Infiltration of T cells was increased in HP piglets at d28. IL-1b and NF-kappa B sub-units mRNA levels were reduced in HP piglets at d7 and d28 respectively; plasma haptoglobin also tended to be reduced at d7. Later in life, pro-inflammatory cytokines secretion in response to high doses of LPS in explants culture was reduced in HP compared to NP piglets. Levels of mRNA coding the NF-kappa B pathway sub-units were increased by the challenge with LPS in NP piglets, but not HP ones. Conclusions/Significance: A high protein level in formula affects the postnatal development of ileal microbiota, epithelial barrier and immune function in piglets and alters ileal response to inflammatory mediators later in life

Le paludisme chez la femme enceinte (A propos de 54 observations au Centre Hospitalier fr Saint-Denis, Hôpital Delafontaine (93))

ANGERS-BU Médecine-Pharmacie (490072105) / SudocSudocFranceF

Caractérisation de cellules dendritiques dans les organes lymphoïdes secondaires et le sang du porc sain et étude de leur activation après infection par le virus de la peste porcine classique

Des cellules dendritiques conventionnelles (cDC) et plasmacytoïdes (pDC) immatures et semi-matures ont été identifiées dans les zones T des organes lymphoïdes secondaires et le sang de porcs sains. Après infection des porcs par le virus de la peste porcine classique, les DC deviennent matures et actives en 24 h en prenant en charge le virus pour initier la réponse immunitaire innée dans les zones T de l amygdale. Les lymphocytes B activés co-localisées avecl antigène viral E2 migrent des centres germinatifs vers les zones T de l amygdale après 48 h. Les pDC sont recrutées dans le sang, mais le nombre de cDC et de lymphocytes y diminuent. Les pDC sont transitoirement activées les zones T de la rate, mais les cDC y expriment l interleukine 10, induisant une réponse humorale et l inhibition de l activité des DC. Les grandes productions d interféron alpha et de TNF alpha par les DC, pourraient induire l apoptose des cellules non infectées et un dysfonctionnement des lymphocytes T.RENNES1-BU Sciences Philo (352382102) / SudocSudocFranceF

A high-protein formula increases colonic peptide transporter 1 activity during neonatal life in low-birth-weight piglets and disturbs barrier function later in life

International audienceDietary peptides are absorbed along the intestine through peptide transporter 1 (PepT-1) which is highly responsive to dietary protein level. PepT-1 is also involved in gut homeostasis, both initiating and resolving inflammation. Low-birth-weight (LBW) neonates are routinely fed a high-protein (HP) formula to enhance growth. However, the influence of this nutritional practice on PepT-1 activity is unknown. Intestinal PepT-1 activity was compared in normal-birth-weight (NBW) and LBW piglets. The effect of HP v. normal-protein (NP) formula feeding on PepT-1 activity and gut homeostasis in LBW piglets was evaluated, during the neonatal period and in adulthood. Flux of cephalexin (CFX) across the tissue mounted in Ussing chambers was used as an indicator of PepT-1 activity. CFX flux was greater in the ileum, but not jejunum or colon, of LBW than NBW piglets during the neonatal period. When LBW piglets were formula-fed, the HP formula increased colonic CFX during the 1st week of life. Later in life, intestinal CFX fluxes and barrier function were similar whether LBW pigs had been fed NP or HP formula. However, colonic permeability of HP- but not NP-fed pigs increased when luminal pH was brought to 6·0. The formyl peptide N-formyl methionyl-leucyl-phenylalanine conferred colonic barrier protection in HP-fed piglets. Heat shock protein 27 levels in the colonic mucosa of HP-fed LBW pigs correlated with the magnitude of response to the acidic challenge. In conclusion, feeding a HP formula enhanced colonic PepT-1 activity in LBW pig neonates and increased sensitivity of the colon to luminal stress in adulthood

Is the colon submitted to nutritional programming? Delayed effect of a high protein formula on colonic physiology in low birth weight piglets

National audienc

Classical swine fever virus induces activation of plasmacytoid and conventional dendritic cells in tonsil, blood, and spleen of infected pigs

Classical swine fever virus (CSFV) compromises the host immune system, causing indirect leucopoenia and disruption of in vitro T cell stimulation capacity. In order to explore the potential role of dendritic cells (DC) in such phenomena, the activation of conventional DC (cDC) and plasmacytoid DC (pDC) in blood and secondary lymphoid organs of infected pigs was investigated in the early time course post-inoculation (pi), together with viral components dissemination and cytokine production in serum. Whereas CD11R1$^{+}$CD172a$^{+}$ cDC frequencies were markedly reduced in blood and spleen, analysis of CD4$^{+}$CD172a$^{+}$ pDC numbers revealed a rapid turn-over of this DC subset in tissues pi. Both subsets matured and were activated after infection, as demonstrated by down-regulation of CD1a, up-regulation of the co-stimulation molecule CD80/86 and expression of cytokines. cDC essentially expressed tumor necrosis factor alpha (TNF-$\alpha$) and interleukin (IL)-10, whereas pDC produced alpha interferon (IFN-$\alpha$) and IL-12. IFN-$\alpha$ and TNF-$\alpha$ productions revealed an enhancement of innate anti-viral immune responses. Detection of antigen activated B lymphocytes in tonsil T-cell areas at 72 h pi, subsequently to the transient translocation of the viral E2 protein within germinal centres at 48 h pi, indicates the initiation of humoral response. This response was also evidenced by an important IL-10 production in serum one week pi. IL-12 expression in organs, as well as transient detection of IL-18 and IFN-$\gamma$ in serum, reflected the initiation of cellular immune responses. However, the uncommonly high levels of TNF-$\alpha$ and IFN-$\alpha$ produced by DC and measured in serum early post-infection, together with IL-10 expression in spleen, could play a role in the disruption of immune system cells, either inducing apoptosis or impairing DC functionalities themselves