Dietary Macronutrients Do Not Differently Influence Postprandial Serum and Plasma Brain-Derived Neurotrophic Factor Concentrations: A Randomized, Double-Blind, Controlled Cross-Over Trial

Objectives: Brain-derived neurotrophic factor (BDNF) plays a role in cognition and metabolism. Specific nutrients can affect fasting BDNF concentrations, which are potentially mediated by insulin and/or glucose. Since macronutrients trigger each a different insulin and glucose response, we examined postprandial effects of meals rich in fat, carbohydrates, or protein on BDNF concentrations. BDNF was analyzed in serum and plasma, since concentration differences can be found between matrices.Methods: Healthy overweight/obese male participants (n = 18) participated in this randomized, double-blind, cross-over trial consisting of three test days with 1 week wash-out periods. Either a high-fat (En% fat, carbohydrates, protein: 52.3, 39.2, 8.0), high-carbohydrate (En% 9.6, 81.5, 8.6) or high-protein meal (En% 10.6, 51.5, 36.9) was consumed on each test day. BDNF concentrations were measured after 0, 60, and 240 min. Glucose and insulin concentrations were measured after 0, 15, 30, 45, 60, 90, 120, and 240 min.Results: BDNF concentrations were higher in serum compared with plasma (P < 0.001). Postprandial BDNF concentrations in serum decreased significantly after the high-fat (P = 0.013) and high-carbohydrate meals (P = 0.040), and showed a trend after the high-protein meal (P = 0.076). No differences were found between meals (P = 0.66). Postprandial BDNF concentrations measured in plasma did not significantly change after the different meals (P = 0.47). As total area under the curve (AUC) for glucose was significantly higher after the high-carbohydrate meal compared with the high-fat (P = 0.003) and high-protein meals (P < 0.001), and the total AUC for insulin was higher after the high-carbohydrate (P < 0.001) and high-protein meals (P < 0.001) compared with the high-fat meal, it seems that acute changes in glucose and insulin do not affect postprandial BDNF concentrations. However, after the high-protein meal, the higher total AUC for glucose correlated with lower serum BDNF concentrations, and a higher maximal increase in glucose correlated with a lower maximal increase in plasma BDNF concentrations. There were no correlations with insulin concentrations after either meal.Conclusion: Serum BDNF concentrations were higher than plasma concentrations. Since postprandial BDNF responses were not different between the meals, we conclude that there is no role for insulin or glucose in regulating postprandial BDNF concentrations.Clinical Trial Registration: [www.ClinicalTrials.gov], identifier [NCT03139890].

Physical properties and processing of Silphium integrifolium seeds to obtain oil and enriched protein meal

Silphium integrifolium Michx. (Silflower) has been a promising subject for domestication as a perennial oilseed crop. This work was carried out to investigate the seed processing aspect of this effort. Selected physical properties of the seed were evaluated, seed milling to obtain enriched kernel fraction was conducted, and initial characterization of the seed protein was performed. There was wide variation in flat seed length (11.54 to 20.75 mm), width (4.61 to 11.76 mm), and thickness (0.92 to 1.63 mm). The thousand seed weight was 23.8 g but the tapped bulk density was only 189.58 g/L due to the presence of wing around the seed’s periphery. The kernel accounted for 56.14% of the seed weight and contained 31.00% oil. An enriched kernel fraction with 79.6% purity was obtained by roller-milling, sifting, and air classification. Linoleic (62.3%) and oleic (19.62%) acids were the major fatty acids in the oil. The defatted enriched kernel fraction contained 63.41% crude protein. Globulin, glutelin, albumin, and prolamin accounted for 55.63%, 19.28%, 16.38%, and 8.71% of the soluble proteins, respectively. At an extraction pH of 9, protein solubility was 62%. Maximum solubility (70%) was obtained at pH 10 while minimum solubility of 9% occurred between pH 4 and 5.5. Aside from the oil, the dehulling of silflower seeds also produced a high-protein defatted meal, which may be used as is or as a starting material for enriching the protein further into a protein isolate.

PSV-B-26 Performance of sunflower protein meal and dried yeast as secondary protein sources in feline diets

The objectives of this study were to assess graded inclusions of sunflower protein meal (SPM; crude protein: 54%, crude fat: 11%, crude fiber: 4%) and dried yeast (DY; crude protein: 50%, crude fat: 3%, crude fiber: 2%) on nutrient digestibility, stool quality, and palatability in adult cats. Both SPM and DY were included at 5% and 10% in replacement of pea protein in a high-protein, chicken-based feline diet to maintain equal macronutrient concentrations across all test diets (formulated to 41% crude protein, 18% crude fat, 3% crude fiber). The study was approved and followed by the facility’s Institutional Animal Care and Use Committee. A standard 2-bowl palatability test over a 2-day period was executed with adult cats (n = 30 each) to determine intake ratios between test diets (5% and 10% SPM or 5% and 10% DY), and test diets vs. control. Total tract nutrient digestibility was evaluated (n = 8 per diet) with 5 days of diet acclimation followed by 5 days of total fecal collection. Stool quality was evaluated on a 1–5 scale, where 1 = hard/formed and 5 = non-formed/diarrhea. All data were analyzed by ANOVA (SAS v9.4) and T-tests post-hoc (Minitab 18). Palatability and stool quality were similar (P > 0.05) between all diets. Protein digestibility was lower for DY-containing diets, compared with control (5% DY at P = 0.0083 and 10% DY at P = 0.0336), but not significantly different for SPM diets (P > 0.05). However, average protein digestibility was >88% across all diets. The alternative protein sources tested showed merit for inclusion to diversify ingredient sources while maintaining palatability in cat diets.

PSV-B-25 Performance of sunflower protein meal and dried yeast as secondary protein sources in canine diets

The objectives of this study were to assess graded inclusions of sunflower protein meal (SPM; crude protein: 54%, crude fat: 11%, crude fiber: 4%) and dried yeast (DY; crude protein: 50%, crude fat: 3%, crude fiber: 2%) on nutrient digestibility, stool quality, and palatability in adult dogs. Both SPM and DY were included at 5% and 10% in replacement of pea protein in a high-protein, chicken-based canine diet to maintain equal macronutrient concentrations across all test diets (formulated to 35% crude protein, 15% crude fat, 3% crude fiber). The study was approved and followed by the facility’s Institutional Animal Care and Use Committee. A standard 2-bowl palatability test over a 2-day period was executed with adult dogs (n = 30 each) to determine intake ratios (IR) between test diets (5% and 10% SPM or 5% and 10% DY), and test diets vs. control. Total tract nutrient digestibility was evaluated (n = 8 per diet) with 5 days of diet acclimation followed by 5 days of total fecal collection. Stool quality was evaluated on a 1–5 scale, where 1 = hard/formed and 5 = non-formed/diarrhea. All data were analyzed by ANOVA (SAS v9.4) and T-tests post-hoc (Minitab 18). With P < 0.05 considered statistically significant, no differences were observed between diets for protein digestibility (all >84% avg) or stool scores (all averages between 2.25–2.50). For DY-containing diets, no significant differences in IR were noted vs. control (IRs = 35:65, 5% DY vs control; 40:60, 10% DY vs. control). However, palatability of control was preferred vs. SPM-containing diets (P< 0.05; IRs = 19:81, 5% SPM vs. control; 29:71, 10% SPM vs. control). Overall, detriments in protein digestibility and stool quality were not evident with DY and SPM, suggesting their viability as alternative protein sources in dog diets.

Persistent Purine Metabolic Abnormality Induces the Aggravation of Visceral Inflammation and Intestinal Microbiota Dysbiosis in Magang Goose

Gout is a disease involving abnormal purine metabolism that is widespread in mammals and birds. Goose is especially susceptible for gout in early stage. However, a few studies investigated the ontogenetic pattern of goslings with purine metabolic abnormality. Our studies were conducted to investigate whether persistent purine metabolic abnormality would lead to aggravation of visceral inflammation and intestinal microbiota dysbiosis in goose. A total of 132 1-day-old Magang geese were randomly divided into six replicates and fed a high-calcium and protein meal-based diet from 1 to 28 days. The experiment lasted for 28 days. Liver and kidney damages were observed in 14- and 28-day-old Magang geese, and liver inflammation increased with increasing age. In 28-day-old Magang geese, serum CAT and liver GSH-Px activity were significantly reduced. Furthermore, jejunum intestinal barrier was impaired and the abundance of Bacteroides was significantly reduced at the genus level. Collectively, the high-calcium and high-protein (HCP) meal-based diet caused liver and kidney damage in 28-day-old Magang geese, leading to hyperuricemia and gout symptoms, and the intestinal barrier is impaired and the intestinal flora is disrupted.

Rheological Study of an Extruded Fish Diet with the Addition of Hydrolyzed Protein Meal

The extrusion of food for human and animal consumption is a unit operation that includes mixing, shearing and force to the materials related to the rheological properties of the materials in the extruder. The present work aims to study the rheological behavior of an extruded fish diet incorporating hydrolyzed protein flour processed by extrusion. The measurement was carried out online with a slit die rheometer, defining the rheological models and parameters that fit the process. During the extrusion process, the raw materials used were hydrolyzed protein meal, fish meal and cassava starch. For the results, the evaluated treatments were adjusted to the Power Law, where an increase in the shear rate decreases the viscosity of the material, corresponding to a pseudoplastic behavior. The incorporation of hydrolyzed protein flour presented a significant effect on the value of n and Klp, increasing the viscosity with the increase in the percentage of inclusion of HPH. The models obtained for the prediction of the viscosity are adjusted to the changes in shear rate, temperature and humidity of the system.