Binding Protein Concentrations Research Articles

A Low-Dose Prebiotic Fiber Supplement Reduces Lipopolysaccharide Binding Protein Concentrations in a Subgroup of Young, Healthy Adults Consuming Low-Fiber Diets

A Low-Dose Prebiotic Fiber Supplement Reduces Lipopolysaccharide Binding Protein Concentrations in a Subgroup of Young, Healthy Adults Consuming Low-Fiber Diets

Metabolic dysfunction-associated steatotic liver disease-associated fibrosis and cardiac dysfunction in patients with type 2 diabetes.

Metabolic dysfunction-associated steatotic liver disease (MASLD), particularly in the presence of liver fibrosis, increases the risk of cardiovascular morbidity and mortality, but the nature of the cardio-hepatic interaction in the context type 2 diabetes mellitus (T2DM) is not fully understood. To evaluate the changes in cardiac morphology and function in patients with T2DM and MASLD-associated liver fibrosis. T2DM patients with MASLD underwent a medical evaluation that included an assessment of lifestyle, anthropometric measurements, vital signs, an extensive laboratory panel, and a standard echocardiography. Liver fibrosis was evaluated using two scores [Fibrosis-4 (FIB4) and Non-alcoholic fatty liver disease-Fibrosis Score (NFS)], and subjects were classified as having advanced fibrosis, no fibrosis, or an indeterminate risk. The correlations between structural and functional cardiac parameters and markers of liver fibrosis were evaluated through bivariate and multiple regression analyses. Statistical significance was set at P < 0.05. Data from 267 T2DM-MASLD subjects with complete assessment was analyzed. Patients with scores indicating advanced fibrosis exhibited higher interventricular septum and left ventricular (LV) posterior wall thickness, atrial diameters, LV end-systolic volume, LV mass index (LVMi), and epicardial adipose tissue thickness (EATT). Their mean ejection fraction (EF) was significantly lower (49.19% ± 5.62% vs 50.87% ± 5.14% vs 52.00% ± 3.25%; P = 0.003), and a smaller proportion had an EF ≥ 50% (49.40% vs 68.90% vs 84.21%; P = 0.0017). Their total and mid LV wall motion score indexes were higher (P < 0.05). Additionally, they had markers of diastolic dysfunction, with a higher E/e' ratio [9.64 ± 4.10 vs 8.44 (2.43-26.33) vs 7.35 ± 2.62; P = 0.026], and over 70% had lateral e' values < 10 cm/second, though without significant differences between groups. In multiple regression analyses, FIB4 correlated with left atrium diameter (LAD; β = 0.044; P < 0.05), and NFS with both LAD (β = 0.039; P < 0.05) and right atrium diameter (β = 0.041; P < 0.01), Moreover, LVMi correlated positively with age and EATT (β = 1.997; P = 0.0008), and negatively with serum sex-hormone binding protein (SHBP) concentrations (β = -0.280; P = 0.004). SHBP also correlated negatively with LAD (β = -0.036; P < 0.05). T2DM patients with markers of MASLD-related liver fibrosis exhibit lower EF and present indicators of diastolic dysfunction and cardiac hypertrophy. Additionally, LVMi and LAD correlated negatively with serum SHBP concentrations.

An overview of interpretability of two models of unbound fraction that are used in combination with the well-stirred model for predicting hepatic clearance of drugs

Hypothetical and experimental models of unbound fraction have been proposed to facilitate predicting the hepatic clearance (CLH) of drugs from values of intrinsic clearance for the unbound drug (CLint-in vitro-unbound) and the well-stirred model (WSM). The hypothetical model (fu-adjusted) is adjusting the unbound fractions determined in plasma in vitro to estimate the maximum unbound fractions at the hepatocytes if each drug-protein complex in plasma becomes fully dissociated at the membrane by any albumin (ALB)-facilitated hepatic uptake mechanism. The model of fu-adjusted is also adjusting the unbound fraction for a pH gradient effect across the membrane. Alternatively, the new experimental model (fu-dynamic) measures the unbound fractions resulting to the dynamic dissociation kinetics from proteins in the presence of plasma and a liver enzyme in an in vitro assay. The objective of this study was to conduct an in-depth analysis of previous CLH predictions made with these unbound fractions in a companion manuscript. Furthermore, a new dataset on transporter substrates was also included in this study. Finally, the physiological basis of fu-adjusted has been redefined to extend its applicability with more drugs. In this case, there are lower concentrations of binding proteins in liver versus plasma that could also explain the higher unbound fractions for that organ. The outcomes associated to additional analyses pointed out that fu-adjusted, again, generally provided the most accurate predictions of CLH because fu-dynamic has generated superior biases of underpredictions or overpredictions. For slowly metabolized drugs bound to ALB, fu-dynamic was definitively less accurate than fu-adjusted. For other drug properties, fu-dynamic fared better but it was still not generally more accurate than fu-adjusted. Furthermore, experimental values of fu-dynamic were sometimes incoherent. For example, drugs bound to alpha-acid glycoprotein (AGP) did not follow the principle of fu-dynamic (i.e., values of fu-dynamic did not correlate with values of CLint-in vitro-unbound) by contrast to those drugs bound to ALB. Therefore, the current experimental setting for fu-dynamic might be unsuitable in some circumstances. Overall, this study confirmed that calculated values of fu-adjusted were as accurate as experimental values of fu-dynamic and can even be more accurate. A guidance on which unbound fraction to use in the WSM is also provided.

Serum retinol binding protein 4 in individuals with essential hypertension and type 2 diabetes: A cross-sectional study.

Cardiometabolic disorders, notably primary hypertension and type 2 diabetes, present substantial global health challenges. The intricate interplay between metabolic and cardiovascular pathways has prompted extensive research into molecular mechanisms linking these conditions. The adipokine Retinol Binding Protein 4 (RBP4), initially recognized for retinol transport, has emerged as a potential biomarker in the network of metabolic and cardiovascular dysfunction. Recent studies implicate RBP4 in insulin resistance and its complications, including hypertension. This study explores RBP4 dynamics in patients with primary hypertension and type 2 diabetes, aiming to contribute valuable insights into diagnostic and therapeutic advancements in managing these interconnected disorders. This cross-sectional study, conducted over 2 years in a tertiary healthcare centre of North India, aimed to investigate the serum concentration of Retinol Binding Protein 4 (RBP4) in 119 participants diagnosed with primary hypertension and type 2 diabetes. Ethical guidelines were strictly followed, and comprehensive clinical assessments, including blood pressure measurements, were performed. RBP4 levels were quantified using an ELISA kit, alongside markers of insulin resistance. Statistical analyses, involving t-tests and correlation assessments, sought to unravel potential associations between RBP4, insulin resistance, and blood pressure parameters using SPSS 20.0. The study comprised 61 healthy control (HC) participants and 58 individuals diagnosed with both essential hypertension and type 2 diabetes (EH+T2D). EH+T2D participants were on average older (45.71 ± 9.29 years vs. 40.34 ± 9.47 years, P = 0.002). Dyslipidemia prevalence was markedly higher in EH+T2D (72.4% vs. 11.4%, P < 0.0001), accompanied by disrupted lipid profiles. Serum RBP4 concentration was significantly elevated in EH+T2D (49.17 ± 19.37 mg/L, P < 0.0001), suggesting its potential role in the shared pathophysiology of primary hypertension and type 2 diabetes. Pearson's correlation analysis revealed associations between RBP4 levels, metabolic, and cardiovascular parameters, underscoring its potential as a link between these conditions. Elevated serum RBP4 levels suggest its potential as a novel biomarker in the shared pathophysiology of primary hypertension and type 2 diabetes. The correlation analysis highlights the intricate interplay between metabolic, lipid, and cardiovascular parameters, emphasizing the need for holistic interventions.

Effects of solid-state fermentation product of yeast supplementation on liver and intestinal health, and resistance of common carp (Cyprinus carpio) against spring viraemia carp virus

This study aimed to investigate the effects of solid-state fermentation products of yeast (SFPY) on liver and intestinal health and disease resistance of common carp (Cyprinus carpio). A total of 200 common carp with an initial average weight of 2.55 ± 0.004 g were divided into 5 groups (4 replications per group and 10 fish per replication), and were fed with one of five diets, including a control diet and 4 diets supplemented with 2‰ (Y2), 3‰ (Y3), 4‰ (Y4), or 5‰ (Y5) SFPY, respectively, for 8 weeks. Results indicated that, the addition of SFPY to the diet of common carp did not affect the growth performance or survival rate of fish (P = 0.253). Interestingly, with the addition of SFPY, the triacylglycerol (TAG) content of the liver presented a linear decreasing tendency (P = 0.004), with significantly decreased in Y4 and Y5 groups (P = 0.035) compared with control. Serum lipopolysaccharide (LPS) content and diamine oxidase (DAO) activity presented a negative linear relationship with the addition of SFPY (P = 0.015, P = 0.030), while serum lipopolysaccharide binding protein (LBP) content first decreased and then increased (P < 0.001). The total antioxidant capacity (T-AOC) in the intestine of fish increased continuously with increasing SFPY supplementation (P = 0.026), reaching the highest level in Y5 group. The villus height in all experimental groups were significantly higher than that in the control group (P < 0.001). Furthermore, compared to the control, adding 3‰ SFPY to the control diet of common carp significantly increased the relative abundance of Fusobacteria (P = 0.018) and decreased that of Proteobacteria (P = 0.039) at phylum level, and increased the relative abundance of Cetobacterium (P= 0.018) and decreased that of Shewanella (P = 0.013) at genus level. Compared with the control, the relative mRNA expression level of spring viraemia of carp virus N protein (SVCV-n) in the kidney was lower than that of the control group without significance and bottomed out in Y4 group (P = 0.138). In conclusion, dietary SFPY enhanced the SVCV resistance capacity of common carp by improving liver and intestinal health and modulating the gut microbiota. Thus, SFPY is a potential feed additive to be used in aquaculture to reduce the huge economic loss of common carp due to SVCV disease. Based on liver TAG content and intestinal villus height, the optimal addition level of SFPY was 3.02‰ and 2.72‰, respectively.

Concentration of fatty acid binding protein as a new indicator of ejaculate fertility

Objective. To determine the marker function of fatty acid binding protein (FABP) concentration in seminal plasma (SP) in order to assess ejaculate fertility used in in vitro fertilization (IVF) treatment of infertility in couples. Materials and methods. The study involved semen samples of 96 men of reproductive age: the study group (n=63) – patients with a decrease in concentration and/or total content of spermatozoa in ejaculate, the comparison group (n=33) – men with normal concentration and number of spermatozoa in ejaculate. The content of FABP in SP was determined by enzyme-linked immunosorbent assay using the test system “FABP – ELISA – BEST” (A-9102, Vector-Best, Russia). In order to determine the informative value of using the concentration of FABP in SP as a criterion of ejaculate fertility of men of the study group, the predictive value of positive and negative IVF results was determined by calculating the diagnostic sensitivity, specificity and efficiency. Results. The content of FABP in SP accounted for 1.29 ± 0.24 ng/mL, the median and interquartile range comprised 1.23 [1.13–1.35] ng/mL, ranging from 1.08 to 2.79 ng/mL. The study revealed statistically significant intergroup differences (Mann-Whitney test U=79.00; p=0.000016), a weak correlation between the level of FABP and the concentration of spermatozoa (R=0.578008) and their number in ejaculate (R=0.583599). The diagnostic sensitivity of the test for FABP in SP of the men of the study group accounted for 81.82%, specificity – 78.95%, efficiency – 80.95%. Conclusion. Seminal plasma FABP can act as a marker of spermatogenesis disorders. The study of this protein in ejaculate provides the accuracy of predicting the outcome of in vitro fertilization.

149 Development of a leaky gut model: Impact of 24-h feed restriction on ileal expression of tight junction proteins in weaned pigs

Abstract Weanling barrows, 26 to 28 d old [n = 90; Duroc terminal line Fast genetics, initial body weight (BW)= 5.63 ± 0.43 kg] were used to evaluate the effect of 24-h complete feed restriction on growth and intestinal integrity. Upon arrival at the NutriQuest modeling center (Fergus Falls, MN), pigs were weighed, blocked by BW, and randomly assigned to 1 of 30 pens. Five treatments were randomly assigned to 6 pens: 1) Positive Control (PC), and 4 treatments that had 24-hr feed restriction (FR); 2) Negative control (NC), 3) Direct Fed Microbial (DFM) A, 4) DFM B, and 5) DFM C. Feed intake and BW were determined weekly and before and after FR. All pigs were fed a common diet. Fifteen pigs were removed prior to FR due to enteric disease. On d 18, feed was removed from pigs on treatments 2 to 5 for 24 h. After 24 h, 8 pigs per treatment were harvested for tissue collection. Feed access was restored to the remaining pigs who were harvested 3 d later. Ileal samples were collected and immediately frozen. Plasma and fecal samples were collected upon arrival, at FR, and 24 h and 4-d post-FR. Ileal expression of claudin-3, occludin, and tight-junction-1 genes was determined using QuantStudio 3 Real Time PCR system. Fold-change in gene expression compared with NC was calculated for each treatment. Plasma samples were analyzed for LPS binding protein (LBP) concentration, and fecal samples were analyzed for myeloperoxidase (MPO) concentration. Pig (n = 75) was the experimental unit for BW, LBP, MPO, and gene expression data. Pen (n = 30) was the experimental unit for feed intake. Data were analyzed using PROC GLIMMIX of SAS. Preplanned orthogonal contrasts were performed to determine the effect of PC vs. 4 FR treatments. To determine the relationship of tight junction gene expression and LBP and MPO, PROC REG of SAS was used. Data are described as PC vs. FR treatments to focus on model development. Final BW for pigs on PC was greater compared with the FR treatments (P &amp;lt; 0.05; Table 1). From 1 to 4 d post-FR, average daily gain (ADG) for FR treatments was greater than PC (P &amp;lt; 0.01). There was no effect of treatment on feed intake or feed efficiency. Plasma LBP and fecal MPO concentrations were greater 24 h post-FR for pigs on PC compared with FR treatments (P &amp;lt; 0.01). Fold change in occludin and claudin-3 expression was greater for PC compared with FR treatments (P ≤ 0.05). For pigs euthanized 24 h post-FR, there was a positive relationship between LBP concentrations and occludin expression (P &amp;lt; 0.02). Twenty-four hour FR in weaned pigs alters ileal tight junction gene expression and plasma LBP concentrations; therefore, a timed FR event may serve as a model for leaky gut.

150 Development of a leaky gut model: Meta-analysis of plasma and fecal markers of leaky gut

Abstract Intestinal integrity can be compromised in livestock and poultry species during stress events, including off-feed events. To develop a leaky gut model, weanling barrows 26 to 28 d old [n = 307; Duroc terminal line Fast genetics, initial body weight (BW) = 5.90 ± 0.47 kg), were used in a total of 6 randomized complete block experiments at the NutriQuest modeling center (Fergus Falls, MN). All trials included positive control (PC) and negative control (NC) treatments. The other treatments evaluated (n = 8) were various strains and levels of direct-fed microbial (DFM) products. With the exception of PC, all treatments had complete 24-h feed restriction (FR) approximately 18 d after arrival. Pigs assigned to PC had ad libitum access to feed. Pigs were housed 3 pigs per pen in 1 of 30 pens, and all pigs were fed a common high-quality basal diet. For 3 trials, pigs received Excede (Zoetis; Parsipanny, NJ) IM upon arrival and were provided gentamycin via water for 3 d post-arrival. For 3 trials, no prophylactic antibiotics were administered. Eighteen days post-arrival, fecal and plasma samples were collected from all pigs and feed was removed from FR pens. After 24 h, plasma and fecal samples were collected from all pigs, and one-half of the pigs per trial were harvested for tissue collection. Four days after FR, samples were collected similarly, and the remaining pigs were harvested. Plasma samples were analyzed for LPS binding protein concentrations (LBP), and fecal samples were analyzed for myeloperoxidase (MPO) concentrations. Data from the PC (n = 90) and NC (n = 92) treatments only were analyzed as Individual Participant Data meta-analysis using PROC MIXED of SAS. Data from all pigs (n = 307) were analyzed using PROC REG of SAS with forward step-wise selection to determine relationships between response variables. Plasma LBP concentrations did not differ between PC and NC 24 h after FR (P = 0.14). However, change in LBP concentrations and the ratio of LBP immediately before and after FR, differed between PC and NC (P &amp;lt; 0.001). For NC, LBP concentrations decreased, and for PC, LBP concentrations increased (Table 1). There was no effect of treatment on fecal MPO concentrations. Using the broader dataset (n = 307), variables that were predictive of plasma LBP concentrations immediately following FR were trial (P &amp;lt; 0.001), treatment (P &amp;lt; 0.001), and fecal MPO concentrations (P &amp;lt; 0.05). Variables that were predictive of change in LBP concentrations before and after FR were trial (P &amp;lt; 0.001), treatment (P &amp;lt; 0.001), and initial BW (P &amp;lt; 0.01). These data, taken with data presented in a companion abstract on ileal tight junction gene expression, suggest that plasma LBP concentrations immediately following a FR event are a useful marker of leaky gut. Fecal MPO concentrations do not consistently respond to FR.

Confounding factors of the expression of mTBI biomarkers, S100B, GFAP and UCH-L1 in an aging population.

To evaluate some confounding factors that influence the concentrations of S100 calcium binding protein B (S100B), glial fibrillary acidic protein (GFAP), andubiquitin carboxyl-terminal hydrolase L-1 (UCH-L1) in older individuals. Indeed, recent guidelines have proposed the combined use of S100B and the "GFAP-UCH-L1" mTBI test to rule out mild traumatic brain injuries (mTBI). As older adults are the most at risk of mTBI, it is particularly important to understand the confounding factors of those mTBI rule-out biomarkers in aging population. The protein S100B and the "GFAP and UCH-L1" mTBI test were measured using Liaison XL (Diasorin) and Alinity I (Abbott), respectively, in 330 and 341 individuals with non-suspected mTBI from the SarcoPhAge cohort. S100B, GFAP and UCH-L1 were all significantly correlated with renal function whereas alcohol consumption, Geriatric Depression Score (GDS), smoking habits and anticoagulant intake were not associated with any of these three biomarkers. Body mass index (BMI) and age were associated with GFAP and UCH-L1 expression while sex and mini-mental state examination (MMSE) were only associated with GFAP. According to the manufacturer's cut-offs for mTBI rule-out, only 5.5 % of participants were positive for S100B whereas 66.9 % were positive for the "GFAP-UCH-L1" mTBI test. All positive "GFAP-UCH-L1" mTBI tests were GFAP+/UCH-L1-. Among individuals with cystatin C>1.55 mg/L, 25 % were positive for S100B while 90 % were positive for the mTBI test. Our data show that confounding factors have different impacts on the positivity rate of the "GFAP-UCH-L1" mTBI test compared to S100B.

Phenomewide Association Study of Health Outcomes Associated With the Genetic Correlates of 25 Hydroxyvitamin D Concentration and Vitamin D Binding Protein Concentration.

While it is known that vitamin D deficiency is associated with adverse bone outcomes, it remains unclear whether low vitamin D status may increase the risk of a wider range of health outcomes. We had the opportunity to explore the association between common genetic variants associated with both 25 hydroxyvitamin D (25OHD) and the vitamin D binding protein (DBP, encoded by the GC gene) with a comprehensive range of health disorders and laboratory tests in a large academic medical center. We used summary statistics for 25OHD and DBP to generate polygenic scores (PGS) for 66,482 participants with primarily European ancestry and 13,285 participants with primarily African ancestry from the Vanderbilt University Medical Center Biobank (BioVU). We examined the predictive properties of PGS25OHD, and two scores related to DBP concentration with respect to 1322 health-related phenotypes and 315 laboratory-measured phenotypes from electronic health records. In those with European ancestry: (a) the PGS25OHD and PGSDBP scores, and individual SNPs rs4588 and rs7041 were associated with both 25OHD concentration and 1,25 dihydroxyvitamin D concentrations; (b) higher PGS25OHD was associated with decreased concentrations of triglycerides and cholesterol, and reduced risks of vitamin D deficiency, disorders of lipid metabolism, and diabetes. In general, the findings for the African ancestry group were consistent with findings from the European ancestry analyses. Our study confirms the utility of PGS and two key variants within the GC gene (rs4588 and rs7041) to predict the risk of vitamin D deficiency in clinical settings and highlights the shared biology between vitamin D-related genetic pathways a range of health outcomes.

Vitamin D Binding Protein (DBP), Free Calcidiol, and Total Calcitriol in Adults from Northern Greece.

An ongoing debate has been raised on whether is better to use total or free calcidiol as a screening test in the population. In winter and summer, free calcidiol, total calcitriol, and vitamin D binding protein (DBP) concentrations were determined by immunoenzymatic assays in 326 adults (161 males, 165 females). These included 99 osteoporotic patients, 53 type 1 and 51 type 2 diabetics, and 123 athletic healthy persons, all from northern Greece. In the whole sample, free calcidiol mean concentrations differed significantly (p < 0.001) between males (5.53 pg/ml) and females (4.68 pg/ml). Free calcidiol was significantly greater in the athletic healthy group (6.02 pg/ml) than in the three patient groups, and lowest in the osteoporosis group (3.69 pg/ml). Total calcitriol mean concentration did not differ significantly between genders in the whole sample (p = 0.896) or in the study groups, except for type 2 diabetics (males 38.33 pg/ml, females 54.52 pg/ml, p = 0.001). It was significantly less in the osteoporotics (34.61 pg/ml) than in the athletic healthy group (41.65 pg/ml, p = 0.037) and type 1 diabetics (43.73 pg/ml, p = 0.030), whereas it did not differ significantly between the other study groups. The DBP mean concentrations were not significantly different between genders in the whole sample and the study groups nor among the study groups (p = 0.467). Comparisons with our previously reported results of total calcidiol suggest the measurement of free calcidiol offers nothing more than that, and total calcitriol is not a sensitive measure for assessing vitamin D status.

Urinary Vitamin D Binding Protein: A Marker of Kidney Tubular Dysfunction in Patients at Risk for Type 2 Diabetes.

Recent studies have reported elevated urinary vitamin D binding protein (uVDBP) concentrations in patients with diabetic kidney disease, although the utility of uVDBP to predict deterioration of kidney function over time has not been examined. Our objective was to assess the association of uVDBP with longitudinal changes in kidney function. Adults at-risk for type 2 diabetes from the Prospective Metabolism and Islet Cell Evaluation (PROMISE) study had 3 assessments over 6 years (n = 727). Urinary albumin-to-creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR) were used as measures of kidney function. Measurements of uVDBP were performed with enzyme-linked immunosorbent assay and normalized to urine creatinine (uVDBP:cr). Generalized estimating equations (GEEs) evaluated longitudinal associations of uVDBP and uVDBP:cr with measures of kidney function, adjusting for covariates. Renal uVDBP loss increased with ACR severity at baseline. Individuals with normoalbuminuria, microalbuminuria, and macroalbuminuria had median log uVDBP:cr concentrations of 1.62 μg/mmol, 2.63 μg/mmol, and 2.48 μg/mmol, respectively, and ACR positively correlated with uVDBP concentrations (r = 0.37; P < .001). There was no significant association between uVDBP and eGFR at baseline. Adjusted longitudinal GEE models indicated that each SD increase both in baseline and longitudinal uVDBP:cr was significantly associated with higher ACR over 6 years (β = 30.67 and β = 32.91, respectively). Conversely, neither baseline nor longitudinal uVDBP:cr measures showed a significant association with changes in eGFR over time. These results suggest that loss of uVDBP:cr over time may be a useful marker for predicting renal tubular damage in individuals at risk for diabetes.

337 Supplementation of a Kaolin and Yeast-Based Feed Additive on Performance of Feedlot Cattle

Abstract The objective of this project was to examine the effectiveness of feeding a kaolin and yeast-based feed additive on the performance of feedlot cattle. Seventy-five steers (initial BW; 545 ± 42.4 kg) were blocked by BW and randomly allocated into 25 blocks of 3 steers (n = 25 per treatment) in a randomized complete block design with 3 treatments including control, low (10 g/day) and high (15 g/day) kaolin and yeast-based feed additive (FA) supplementation. The steers were fed a finishing diet consisting of 7% corn silage, 1% straw, and 92% corn-based concentrate (DM basis). The duration of the feeding period was 120 days. Supplementation of high grain finishing diet with FA did not affect feed intake (average, 12.4 kg/d), final BW (average, 768 kg), averaged daily gain (average, 1.77 kg/d), carcass traits, and abscessed livers. However, increasing the feeding of FA (0, 10, 15 g/d) to finishing steers linearly (P = 0.05) improved feed efficiency from 0.139 to 0.143 and 0.148 kg gain/kg feed and linearly (P = 0.06) improved net energy for maintenance from 2.05 to 2.10 and 2.15 Mcal/kg and net energy for growth from1.39 to 1.43 and 1.47 Mcal/kg, respectively. Fecal IgA concentration linearly (P = 0.06) increased from 15.0 to 22.7 and 30.1 µg/g with increasing FA addition, suggesting an improvement in nutrient absorption, and potentially better gut health. The increasing addition of FA also linearly (P = 0.03) increased plasma lipopolysaccharide binding protein (LBP) concentration from 46.3 to 56.2 and 64.7 µg/mL but decreased blood total antioxidants from 0.282 to 0.251 and 0.204 mM. These results suggest that the addition of FA may support gut health.

253 Understanding the Health Benefits of Feeding Treated Wheat Straw for Weanling Pigs

Abstract Two experiments were conducted to understand the growth and health benefits of including treated wheat straw in weanling pig diets. The first experiment evaluated feeding treated versus untreated wheat straw on young pig growth performance and localized immunological markers. One hundred and ninety-two (PIC 359 x Yorkshire) pigs were weaned at 26.8 ± 1.1 d old (8.3 ± 1.1 kg) and randomly allotted to 24 pens with 8 pigs per pen. Three dietary treatments were fed over a 28-d period, control (CON), control plus 5% untreated wheat straw (UWS), and control plus 5% treated wheat straw (TWS). Diets were formulated to meet or exceed all nutrient requirements of NRC, 2012. Growth performance data was recorded on a weekly basis. One pig per pen (equal number of males and females) was randomly selected for sacrifice and sample collection on d 28. The second experiment evaluated the impact of 5% dietary TWS on the local and systemic health of nursery pigs experiencing a vaccination-induced immune challenge. Twenty barrows (PIC 800 x Yorkshire) were weaned at 27.7 ± 0.75 d (8.6 ± 1.2 kg) and assigned to four pens, with 5 pigs per pen. A heavy and light-weight pen for each treatment (CON and TWS) resulted. All pigs were sacrificed for sample collection on d 42. In both experiments, before euthanasia, blood was collected to assess plasma immunoglobulin A (IgA) and intestinal fatty acid binding protein (iFABP) concentration. Upon sacrifice, segments of the distal ileum and ascending colon were removed to collect mucosal scrapings for the analysis of localized immunological markers interleukin (IL) 6 , IL-10, IL-12, and tumor necrosis factor-alpha (TNF-α). In experiment one, overall ADG and ADFI were similar among treatments. Gain-to-feed ratio of TWS pigs was greater (P &amp;lt; 0.05) than that of UWS pigs and tended to be greater (P = 0.07) than that of CON pigs (0.70, 0.67, and 0.68, respectively; SEM = 0.01). Both straw treatments decreased the expression of ileal and colonic mucosa IL-6, in addition with less expression of ileal IL-12. Plasma IgA concentrations in UWS pigs were greater than those in CON and TWS pigs (P &amp;lt; 0.05). In experiment two, TWS pigs had greater gene expression of colonic TNF-α and IL-6 (P &amp;lt; 0.05). Ileal gene or protein expression of markers did not differ, nor did amounts of plasma IgA or iFABP. Overall, feeding 5% treated wheat straw in the nursery pig diet does not negatively impact growth and results in increased feed efficiency. Nursery diets with 5% treated wheat straw can impact the expression of immune markers in the gut, but the question of how this is related to performance and overall health needs further elucidation.

Investigating the Association Between Diet-Induced "Leaky Gut" and the Development of Prediabetes.

Chronic consumption of a high-calorie diet compromises the gut microbiota and the integrity of the intestinal wall, which causes translocation of bacterial lipopolysaccharides (LPS) into the blood. This elicits the secretion of pro-inflammatory cytokines, resulting in inflammation. However, how a high-fat high carbohydrate diet affects intestinal permeability and its possible role in the development of prediabetes have not been investigated. This study investigated the effects of HFHC diet-induced prediabetes on gut microbiota and intestinal permeability in male Sprague Dawley rats. The animals were randomly assigned into the non-prediabetic (NPD) and diet-induced prediabetic (PD) groups (n=6) for 20 weeks. Then, the fecal samples were analyzed to measure the gut microbiota level of Firmicutes, Bacteroidetes, and Proteobacteria in both animal groups. Blood glucose, plasma insulin, serum zonulin, plasma LPS, soluble CD14, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), and intestinal fatty-acid binding protein (IFABP) concentrations were measured. The PD group had a reduction in the Firmicutes and an increase in Bacteroidetes and Proteobacteria levels compared to those in the NPD group. Blood glucose, insulin concentration, serum zonulin, and plasma sCD14 concentrations in the PD group increased significantly, while plasma LPS concentrations were similar to the NPD group. Concentrations of plasma TNF-α, IL-6, CRP, and IFABP, an intracellular protein expressed in the intestine, increased in PD compared to the NPD group. the study results cumulatively suggest that chronic consumption of the HFHC diet may be associated with the dysregulation of gut microbiota, leading to increased intestinal permeability.

21 Intentionally Induced Barrier Dysfunction Causes Inflammation, Decreases Growth, and Alters Carcass Characteristics of Feedlot Cattle

Abstract There are a variety of acute and chronic psychological and physical stressors associated with management practices used in beef production systems. Primary challenges in feedlot cattle include heat stress, acute and subacute acidosis, weaning, transportation, feed deprivation/restriction, and social mixing/crowding. These stressors disturb the homeostatic state of the host and microbiome and cause acute or chronic inflammation resulting in damage to the gastrointestinal tract (GIT) epithelial barrier that leaves the animal vulnerable to enteric pathogens and toxins. A breach of the small intestinal barrier (leaky gut) allows unwanted pathogens and toxins to infiltrate into blood, causing infection, depressed feed intake, and diverts nutritional resources away from anabolic processes. We have demonstrated that intentionally inducing GIT inflammation in feedlot cattle with aspirin, which is known to cause mucosal injury and increase GIT barrier dysfunction, provides a model system to better understand the metabolic cost of leaky gut in grain-fed feedlot cattle. Indeed, aspirin increased leakage of chromium-EDTA into urine, raised serum concentrations of lipopolysaccharide binding protein (LBP), decreased growth by 4.5 to 8.5%, and re-partitioned carcass components from lean tissue (rib-eye area) into fat. Thus, the chronic inflammatory effects of leaky gut have the potential to create a significant economic loss. Our work also shows that in-feed administration of monensin and tylosin have offered a solution to the non-specific immune response observed in grain-fed cattle by increasing jejunal villus height to crypt depth ratio, diminishing leaky gut, and decreasing serum LBP. Finally, we have observed that molasses based liquid supplements increase ruminal butyrate concentration, resulting in improved gut barrier function, decreased serum inflammatory markers, and greater DMI and ADG in newly received feedlot cattle fed a 30% roughage diet.

Intestinal barrier disruption with Plasmodium falciparum infection in pregnancy and risk of preterm birth: a cohort study

Malaria in early pregnancy is a risk factor for preterm birth and is associated with sustained inflammation and dysregulated angiogenesis across gestation. This study investigated whether malaria is associated with increased gut leak and whether this contributes to systemic inflammation, altered angiogenesis, and preterm birth. We quantified plasma concentrations of gut leak markers, soluble CD14 (sCD14) and lipopolysaccharide binding protein (LBP) from 1339 HIV-negative pregnant Malawians at <24 weeks gestational age. We assessed the relationship of sCD14 and LBP concentrations with markers of inflammation, angiogenesis, and L-arginine bioavailability and compared them between participants with and without malaria, and with and without preterm birth. Plasma concentrations of sCD14 and LBP were significantly higher in participants with malaria and were associated with parasite burden (p <0.0001, both analyses and analytes). The odds ratio for preterm birth associated with one log sCD14 was 2.67 (1.33 to 5.35, p=0.006) and 1.63 (1.07-2.47, p=0.023) for LBP. Both gut leak analytes were positively associated with increases in proinflammatory cytokines CRP, sTNFR2, IL18-BP, CHI3L1 and Angptl3 (p <0.05, all analytes) and sCD14 was significantly associated with angiogenic proteins Angpt-2, sENG and the sFLT:PlGF ratio (p <0.05, all analytes). sCD14 was negatively associated with L-arginine bioavailability (p <0.001). Malaria in early pregnancy is associated with intestinal barrier dysfunction, which is linked to an increased risk of preterm birth. Open Philanthropy, Canadian Institutes of Health Research, Canada Research Chair program, European and Developing Countries Clinical Trials Partnership, Bill & Melinda Gates Foundation.

Cytosolic concentrations of actin binding proteins and the implications for in vivo F-actin turnover.

Understanding how numerous actin-binding proteins (ABPs) work in concert to control the assembly, organization, and turnover of the actin cytoskeleton requires quantitative information about the levels of each component. Here, we measured the cellular concentrations of actin and the majority of the conserved ABPs in Saccharomyces cerevisiae, as well as the free (cytosolic) fractions of each ABP. The cellular concentration of actin is estimated to be 13.2 µM, with approximately two-thirds in the F-actin form and one-third in the G-actin form. Cellular concentrations of ABPs range from 12.4 to 0.85 µM (Tpm1> Pfy1> Cof1> Abp1> Srv2> Abp140> Tpm2> Aip1> Cap1/2> Crn1> Sac6> Twf1> Arp2/3> Scp1). The cytosolic fractions of all ABPs are unexpectedly high (0.6-0.9) and remain so throughout the cell cycle. Based on these numbers, we speculate that F-actin binding sites are limited in vivo, which leads to high cytosolic levels of ABPs, and in turn helps drive the rapid assembly and turnover of cellular F-actin structures.

Measurement of an intestinal biomarker during poisonings from select toxicants and toxins

Introduction Intestinal toxicity can occur following ingestion of various drugs, chemicals, and toxins. Intestinal fatty acid binding protein is a cytosolic protein specific to intestinal epithelial cells released into the systemic circulation following intestinal injury. Understanding intestinal toxicity in poisoning has the potential to explain mechanisms of toxicity and gastrointestinal symptoms. Methods Plasma samples were retrospectively analysed for intestinal fatty acid binding protein in 25 healthy controls and in those poisoned with Gloriosa superba (n = 18), Thevetia peruviana (n = 26), organophosphates (in various solvents) (n = 17), paracetamol (n = 14), glyphosate (n = 20), 2-methyl-4-chlorophenoxyacetic acid (n = 18) and propanil (n = 19). Results Median peak plasma intestinal fatty acid binding protein concentrations were significantly higher in patients poisoned with Gloriosa superba (2,994.1 µg/L; interquartile range 600.0–5,158.2, P < 0.001), Thevetia peruviana (1,292.5 µg/L; interquartile range 760.3 − 2,076.2; P < 0.001), glyphosate (1,803.6 µg/L; interquartile range 225.7–8,927.7; P < 0.001), 2-methyl-4-chlorophenoxyacetic acid (1,236.2 µg/L; interquartile range 192.6 − 1,709.7; P = 0.010), paracetamol (1,066.5 µg/L; interquartile range 512.9 − 1,336.9; P = 0.035), and organophosphate poisoning (729.8 µg/L; interquartile range 431.5 − 1,588.2; P = 0.046) than in healthy controls (221.6 µg/L; interquartile range 134.8 − 460.1). Median intestinal fatty acid binding protein was not statistically significantly increased compared to controls after propanil poisoning (630.0 µg/L; interquartile range 23.5 − 1,390.3; P = 0.423). Conclusions Our pilot study describes intestinal injury assessed by elevated plasma intestinal fatty acid binding protein concentrations following the ingestion of several poisons. This serves as a foundation for further exploration into enterocyte damage in toxicology.

Aging Increases Enterocyte Damage during a 3-Hour Exposure to Very Hot and Dry Heat: A Preliminary Study.

Profound heat stress can damage the gastrointestinal barrier, leading to microbial translocation from the gut and subsequent systemic inflammation. Despite the greater vulnerability of older people to heat wave-related morbidity and mortality, it is unknown if age modulates gastrointestinal barrier damage and inflammation during heat stress. Therefore, the aim of this study was to determine if aging impacted enterocyte damage and systemic inflammatory responses to a 3-h exposure to very hot and dry (47 °C, 15% humidity) heat with accompanying activities of daily living (intermittent activity at 3 METS). Data from 16 young (age 21 to 39 years) and 16 older (age 65 to 76 years) humans were used to address this aim. In each group, log-transformed plasma concentrations of intestinal fatty acid binding protein (I-FABPlog), interleukin-8 (IL-8log), and tissue factor (TFlog) were assessed as indices of enterocyte damage, systemic inflammation, and blood coagulation, respectively, before and after the 3-h heat exposure. In the younger cohort, I-FABPlog concentration did not increase from pre to post heat exposure (p = 0.264, d = 0.20), although it was elevated in the older group (p = 0.014, d = 0.67). The magnitude of the increase in I-FABPlog was greater in the older participants (p = 0.084, d = 0.55). Across all participants, there was no correlation between the change in core temperature and the change in IFABPlog. There was no change in IL-8log in the younger group (p = 0.193, d = 0.23) following heat exposure, but we observed a decrease in IL-8log in the older group (p = 0.047, d = 0.48). TFlog decreased in the younger group (p = 0.071, d = 0.41), but did not change in the older group (p = 0.193, d = 0.15). Our data indicate that I-FABPlog concentration (an index of enterocyte damage) is increased in older humans during a 3-h extreme heat exposure. Future studies should determine whether this marker reflects increased gastrointestinal barrier permeability in older individuals during heat exposure.