Dietary modulation of the gut microbiota impacts human health. Here we investigated the hitherto unknown effects of resistant starch type 4 (RS4) enriched diet on gut microbiota composition and short-chain fatty acid (SCFA) concentrations in parallel with host immunometabolic functions in twenty individuals with signs of metabolic syndrome (MetS). Cholesterols, fasting glucose, glycosylated haemoglobin, and proinflammatory markers in the blood as well as waist circumference and % body fat were lower post intervention in the RS4 group compared with the control group. 16S-rRNA gene sequencing revealed a differential abundance of 71 bacterial operational taxonomic units, including the enrichment of three Bacteroides species and one each of Parabacteroides, Oscillospira, Blautia, Ruminococcus, Eubacterium, and Christensenella species in the RS4 group. Gas chromatography–mass spectrometry revealed higher faecal SCFAs, including butyrate, propionate, valerate, isovalerate, and hexanoate after RS4-intake. Bivariate analyses showed RS4-specific associations of the gut microbiota with the host metabolic functions and SCFA levels. Here we show that dietary RS4 induced changes in the gut microbiota are linked to its biological activity in individuals with signs of MetS. These findings have potential implications for dietary guidelines in metabolic health management.

The objective of these experiments was to establish the relationship of plasma ghrelin concentrations with feed intake and hormones indicative of nutritional state of cattle. In Exp.1, 4 steers (BW 450 +/- 14.3 kg) were used in a crossover design to compare plasma ghrelin concentrations of feed-deprived steers with those of steers allowed to consume feed and to establish the relationship of plasma ghrelin concentrations with those of GH, insulin (INS), glucose (GLU), and NEFA. After adaptation to a once-daily feed offering (0800), 2 steers continued the once-daily feeding schedule (FED), whereas feed was withheld from the other 2 steers (FAST). Serial blood samples were collected via indwelling jugular catheter from times equivalent to 22 h through 48 h of feed deprivation. Average plasma ghrelin concentrations were greater (P < 0.001) in FAST compared with FED (690 and 123 +/- 6.5 pg/mL) steers. Average plasma ghrelin concentrations for FED steers prefeeding were elevated (P < 0.001) when compared with those postfeeding (174 and 102 +/- 4.2 pg/mL, respectively). Average plasma GH concentration was elevated (P < 0.05) for FAST steers compared with FED steers. Plasma GLU concentrations were not different; however, for FAST steers, NEFA concentrations were elevated (P < 0.001) and INS concentrations were decreased (P < 0.001). In Exp. 2, 4 steers (BW 416 +/- 17.2 kg) were used in a crossover design to determine the effects of i.v. injection of bovine ghrelin (bGR) on plasma GH, INS, GLU, and NEFA concentrations; length of time spent eating; and DMI. Steers were offered feed once daily (0800). Serial blood samples were collected from steers via indwelling jugular catheter. Saline or bGR was injected via jugular catheter at 1200 and 1400. A dosage of 0.08 microg/kg of BW bGR was used to achieve a plasma ghrelin concentration similar to the physiological concentration measured in a FAST steer in Exp. 1 (1,000 pg/mL). Injection of bGR resulted in elevated (P < 0.005) plasma GH concentrations after the 1200 but not the 1400 injection. Plasma INS, GLU, and NEFA concentrations were not affected by bGR injection. For the combined 1-h periods postinjection, length of time spent eating was greater (P = 0.02) and DMI tended to be increased (P = 0.06) for bGR steers. These data are consistent with the hypothesis that ghrelin serves as a metabolic signal for feed intake or energy balance in ruminants.

Persistent infection with bovine viral diarrhea virus (BVDV) serves as a reservoir for the perpetuation of infection in cattle populations and causes a range of adverse effects on the health of the host. To study the interactions of the virus with the host, gene expression was compared in the blood of persistently infected (PI) and uninfected steer, and in the blood and tissues of PI fetuses, transiently infected (TI), and uninfected bovine fetuses. Microarray analysis of PI steer blood revealed differential gene expression indicative of an interferon (IFN) response including genes involved in cell cycle regulation, which may contribute to long-term adverse effects. Upregulation of IFN-stimulated genes (e.g., ISG15, PKR) and RNA helicases (RIG-I, LGP2, MDA-5) was identified in both PI fetal and steer blood in comparison to controls, indicating a continued stimulation of the innate antiviral response as a result of the persistent viremia. ISG15 was studied in further detail, implicating reticular cells as basal producers of ISG15 in the spleen, in addition to endothelial and macrophage-like cells in infected spleen. Consequences of chronic IFN pathway activation in PI cattle may include growth- and immunosuppression, the pathogenesis of which is still poorly understood. This study lends new insights into the interactions between BVDV and its host, and can serve as a model for studies of the role of the IFN system in persistent infections.

This study determined whether estradiol regulates insulin-like growth factor (IGF)-I and IGF binding proteins (IGFBPs) in the pituitary gland, hypophyseal stalk median eminence (SME), and circulation concomitantly with effects on LH. Ovariectomized ewes received an estradiol implant or no implant during the anestrous season and were slaughtered 80 days later. Estradiol suppressed serum LH to a greater extent during anestrus than after onset of the breeding season (Days 60 and 75). Amounts of mRNA for LHbeta subunit were decreased by estradiol, but mRNA for alpha and FSHbeta subunits were not affected. Estradiol increased serum IGF-I, IGFBP-3, and IGFBP-4 throughout the treatment period, but it did not influence other IGFBPs in serum. In response to estradiol, pituitary IGFBP-2 tended to increase and mRNA for IGFBP-2 increased twofold. Other IGFBPs in the pituitary gland were not influenced by estradiol. In the SME, IGFBP-2, IGFBP-5, and the 40-kDa IGFBP-3 were increased by estradiol. Thus, estradiol influences both the IGF and gonadotropin systems in sheep. Estradiol influences on gonadotroph function may be mediated by alterations in the IGF system.

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Protein supplementation during a strength and conditioning program resulted in changes in IGF-I concentrations.

Adverse experiences early in life have the potential to disrupt normal brain development and create stress response channels in preterm infants that are different from those observed in term infants. Animal models show that epigenetic modifications mediate the effects of maternal separation and environmental stress on susceptibility to disease and psychobehavioral problems later in life. Epigenetic research has the potential to lead to the identification of biological markers, gene expression profiles, and profile changes that occur overtime in response to early-life experiences. Combined with knowledge gained through the use of advanced technologies, epigenetic studies have the promise to refine our understanding about how the brain matures and functions from multiple perspectives including the effect of the environment on brain growth and maturation. Such an understanding will pave the way for care practices that will allow the premature brain to develop to its full capacity and will lead to the best possible outcomes. Neonatal epigenetic research is emerging and rapidly advancing. As scientists overcome biological, technical, and cost-related challenges, such research has a great potential in determining key environmental factors that affect the preterm genome, allowing for targeted interventions. The purpose of this article is to explore existing literature related to epigenetic mechanisms that potentially mediate the effects of the environment on preterm infant brain development.

Two experiments were conducted to determine whether 1) administration of estradiol-173 (E2) implants to barrows elevates serum concentrations of E2 to levels similar to those of adult boars and subsequently affects the anterior pituitary gland IGF system and 2) administration of E2 to barrows increases serum concentrations of E2, serum and anterior pituitary concentrations of IGF-I, and relative amounts of serum and anterior pituitary IGF-binding proteins (IGFBP), vs boars and unimplanted barrows. In Exp. 1, 20 crossbred barrows (150 +/- 6 d, 103 +/- 8 kg) were administered varying number of E2 implants (0, 2, 3, 4; n = 5/group) on d 1. Blood samples were collected weekly by jugular venipuncture, beginning on d 1. Pigs were killed on d 36 when a blood sample and anterior pituitary were collected. Serum concentrations of E2 were increased (P < 0.05) in pigs with 2,3, and 4 implants vs 0 implants, but no difference (P > 0.05) was detected in serum concentrations of E2 among pigs with 2, 3, and 4 implants. Orthogonal contrasts identified that three or four E2 implants were necessary to increase serum concentrations of E2 to that similar to boars. Serum and anterior pituitary concentrations of IGF-I were increased (P < 0.05) in pigs with 2, 3, and 4 implants vs 0 implants. Relative amounts of anterior pituitary IGFBP-2 and - 5 increased (P < 0.05) in response to administration of E2. In Exp. 2, three treatment groups were randomly allotted by litter; boars (n = 11), E2-implanted barrows (n = 9), and unimplanted barrows (n = 12). A blood sample was taken from all pigs on d 1 and every 14 d thereafter. Implanted pigs received four implants on d 1. Pigs were killed on d 91, when a blood sample and anterior pituitary were collected. Mean serum concentrations of E2 were greater (P < 0.05) in implanted pigs vs boars. Mean serum concentrations of IGF-I (ng/mL) were greater (P < 0.05) in boars (238.7 +/- 6.8) than in implanted barrows (170.2 +/- 8.9) and unimplanted (150.4 +/- 6.7) pigs and tended to be greater (P = 0.08) in implanted vs unimplanted pigs. Mean anterior pituitary concentrations of IGF-I (ng/mg tissue) were greater (P < 0.05) in implanted (773.6 +/- 57.0) pigs than boars (251.9 +/- 51.6) and unimplanted (185.6 +/- 49.4) pigs. Relative amounts of serum IGFBP-2 were greater (P < 0.05) in implanted pigs vs boars. Relative amounts of anterior pituitary IGFBP-2 and -5 were greater (P < 0.05) in boars than in implanted and unimplanted pigs. These data suggest that E2 may influence components of the porcine IGF system in the serum and anterior pituitary. Other gonadal factors present in boars may additionally affect the serum and anterior pituitary IGF system.