Influence of postruminal casein infusion and exogenous glucagon-like peptide 2 administration on the jejunal mucosal transcriptome in cattle.

We previously demonstrated that postruminal casein infusion and exogenous glucagon-like peptide 2 (GLP-2) administration independently stimulated growth and carbohydrase activity of the pancreas and jejunal mucosa in cattle. The objective of the current study was to profile the jejunal mucosal transcriptome of cattle using next-generation RNA sequencing in response to postruminal casein infusion and exogenous GLP-2. Twenty-four Holstein steers [250 ± 23.1 kg body weight (BW)] received a continuous abomasal infusion of 3.94 g raw corn starch/kg of BW combined with either 0 or 1.30 g casein/kg of BW for 7 d. Steers received subcutaneous injections at 0800 and 2000 h to provide either 0 or 100 µg GLP-2/kg of BW per day. At the end of the 7-d treatment period, steers were slaughtered for collection of the jejunal mucosa. Total RNA was extracted from jejunal mucosal tissue, strand-specific cDNA libraries were prepared, and RNA sequencing was conducted to generate 150-bp paired-end reads at a depth of 40 M reads per sample. Differentially expressed genes (DEG), KEGG pathway enrichment, and gene ontology enrichment were determined based on the FDR-corrected P-value (padj). Exogenous GLP-2 administration upregulated (padj < 0.05) 667 genes and downregulated 1,101 genes of the jejunal mucosa. Sphingolipid metabolism, bile secretion, adherens junction, and galactose metabolism were among the top KEGG pathways enriched with upregulated DEG (padj < 0.05) in response to exogenous GLP-2 administration. The top gene ontologies enriched with upregulated DEG (padj < 0.05) in response to exogenous GLP-2 administration included nutrient metabolic processes, brush border and bicellular tight junction assembly, and enzyme and transporter activities. Exogenous GLP-2 administration increased or tended to increase (padj < 0.10) brush border carbohydrase (MGAM, LCT, TREH), hexose transporter (SLC5A1, SLC2A2), and associated transcription factor (HNF1, GATA4, KAT2B) mRNA expression of the jejunal mucosa. Gene ontologies and KEGG pathways that were downregulated (padj < 0.05) in response to exogenous GLP-2 were related to genetic information processing. Postruminal casein infusion downregulated (padj < 0.05) 7 jejunal mucosal genes that collectively did not result in enriched KEGG pathways or gene ontologies. This study highlights some of the transcriptional mechanisms associated with increased growth, starch assimilation capacity, and barrier function of the jejunal mucosa in response to exogenous GLP-2 administration.

Efficiency of protein combinations in diets for Rhamdia quelen: growth, digestive and metabolic biochemistry and nutrient deposition.

This study was conducted to determine the best combination of protein sources in diets for jundiá, based on growth, metabolism, and nutrient deposition. Five protein combinations were tested: casein + fish meal (control), casein + gelatin, casein + albumin, casein + albumin + fish meal, and albumin + fish meal, in diets containing 370 g Kg-1 of crude protein and 13.4 MJ Kg-1 of digestible energy. The fish (9.38 ± 0.12 g) were allocated in a water recirculation system at a density of 3.35 g L-1 per experimental unit and fed until apparent satiety for 40 days with the diets. The fish fed with the control diet had the highest final weight, specific growth rate, protein and feed efficiency ratio, protein retention, and best apparent feed conversion. On the other hand, fish that received casein + albumin and albumin + fish meal diets showed worse results in growth and body protein retention, low trypsin and chymotrypsin activity, and high intestinal amylase activity. Therefore, the combination referred to as control (casein + fish meal) conclusively provides the best rhythm for nutrient digestion and metabolism processes, enabling fish to reach greater growth and retention of body protein with low whole-fish fat content.

The effect of probiotics and casein supplementation on aerobic capacity parameters of male soccer players.

BACKGROUND: In the realm of sports science, nutrition is a well-established pillar for athletes' training, performance, and post-workout recovery. However, the role of gut microbiota, often overlooked, is a novel and intriguing aspect that can significantly impact athletic performance. With this in mind, our study ventures into uncharted territory, investigating the effect of probiotic and casein supplementation on the aerobic capacity of male soccer players. METHOD: A double-blinded and placebo-controlled study was conducted with 44 male soccer players (Age: 22.81 ± 2.76 yr, Height: 177.90 ± 6.75 cm, Weight: 67.42 ± 8.44 kg). The participants were subjected to the Bruce test in the beginning; then, they were randomly divided into four groups, each consisting of 11 people: probiotics (PRO), casein (CAS), probiotics with casein (PRO+CAS), and placebo (PLA). PRO group was given one probiotic capsule (containing strains of Lactiplantibacillus plantarum BP06, Lacticaseibacillus casei BP07, Lactobacillus acidophilus BA05, Lactobacillus delbrueckii BD08 bulgaricus, Bifidobacterium infantis BI04, Bifidobacterium longum BL03, Bifidobacterium breve BB02 and Streptococcus salivarius thermophilus BT01, with a total dose of 4.5 × 1011 CFU) during dinner, while the CAS group consumed 20 grams of casein powder 45 minutes before bed. The PRO+CAS group was given one probiotic capsule during dinner and 20 grams of casein powder 45 minutes before bed. The participants in the PLA group were given one red capsule (containing 5 grams of starch) during dinner. All participants were instructed to take the supplements only on training days, three times a week for four weeks. The maximal oxygen consumption (VO2max), Ventilatory Threshold (VT), Time-to-exhaustion (TTE), Respiratory Compensation Point (RCP), Isocapnic area Time (Time-IC), Isocapnic area oxygen consumption (VO2-IC), and Hypocapnic Hyperventilation area Time (Time-HHV), after the Bruce test were Measured. All data were analyzed using SPSS Windows software, mixed repeated measure ANOVA, and Bonferroni post hoc test at p < 0.05 level. RESULTS: The current study's findings illustrated that, after the intervention, TTE (p = 0.01) and RCP (p = 0.01) were significantly improved in PRO+CAS compared to the PLA group. No significant difference was observed between PRO and PLA (p = 0.52), PRO and CAS (p = 0.999), PRO and PRO+CAS (p = 0.9), CAS and PLA (p = 0.65), CAS and PRO+CAS (p = 0.73) in TTE. In addition, no significant difference was observed between PRO and CAS (p = 0.999), PRO and PLA (p = 0.40), PRO and PRO+CAS (p = 0.999), CAS and PLA (p = 0.263), CAS and PRO+CAS (p = 0.999) in RCP. Time-HHV was significantly higher in PRO+CAS (p = 0.000) and CAS (p = 0.047) compared to the PLA group. However, no significant difference was observed in the Time-HHV between PRO and CAS (p = 0.999), PRO and PRO+CAS (p = 0.25), PRO and PLA (p = 0.12), and CAS and PRO+CAS (p = 0.57). Additionally, all the groups had no significant differences in VO2max, VT1, VO2-IC and Time-IC. CONCLUSION: The findings showed that consuming probiotics and casein could relatively improve the aerobic capacity of male soccer players. Nevertheless, simultaneous consumption of probiotics and casein had a more pronounced effect on aerobic capacity indicators, especially TTE and Time-HHV.

Protein-based oral rehydration solutions for patients with an ileostomy: A randomised, double-blinded crossover study.

BACKGROUND & AIM: Patients with an ileostomy are at increased risk of dehydration and sodium depletion. Treatments recommended may include oral rehydration solutions (ORS). We aimed to investigate if protein type or protein hydrolysation affects absorption from iso-osmolar ORS in patients with an ileostomy. METHODS: This was a randomised, double-blinded, active comparator-controlled 3 × 3 crossover intervention study. We developed three protein-based ORS with whey protein isolate, caseinate or whey protein hydrolysate. The solutions contained 40-48 g protein/L, 34-45 mmol sodium/L and had an osmolality of 248-270 mOsm/kg. The patients ingested 500 mL/d. The study consisted of three 4-week periods with a >2-week washout between each intervention. The primary outcome was wet-weight ileostomy output. Ileostomy output and urine were collected for a 24-h period before and after each intervention. Additionally, blood sampling, dietary records, muscle-strength tests, bioimpedance analyses, questionnaires and psychometric tests were conducted. RESULTS: We included 14 patients, of whom 13 completed at least one intervention. Ten patients completed all three interventions. Wet-weight ileostomy output did not change following either of the three interventions and did not differ between interventions (p = 0.38). A cluster of statistically significant improvements related to absorption was observed following the intake of whey protein isolate ORS, including decreased faecal losses of energy (-365 kJ/d, 95% confidence interval (CI), -643 to -87, p = 0.012), potassium (-7.8 mmol/L, 95%CI, -12.0 to -3.6, p = 0.001), magnesium (-4.0 mmol/L, 95%CI, -7.4 to -0.7, p = 0.020), improved plasma aldosterone (-4674 pmol/L 95%CI, -8536 to -812, p = 0.019), estimated glomerular filtration rate (eGFR) (2.8 mL/min/1.73 m2, 95%CI, 0.3 to 5.4, p = 0.03) and CO2 (1.7 mmol/L 95%CI, 0.1 to 3.3, p = 0.04). CONCLUSION: Ingestion of 500 mL/d of iso-osmolar solutions containing either whey protein isolate, caseinate or whey protein hydrolysate for four weeks resulted in unchanged and comparable ileostomy outputs in patients with an ileostomy. Following whey protein isolate ORS, we observed discrete improvements in a series of absorption proxies in both faeces and blood, indicating increased absorption. The protein-based ORS were safe and well-tolerated. Treatments should be tailored to each patient, and future studies are warranted to explore treatment-effect heterogeneity and whether different compositions or doses of ORS can improve absorption and nutritional status in patients with an ileostomy. GOV STUDY IDENTIFIER: NCT04141826.

Prolonged Consumption of A2 ß-Casein Milk Reduces Symptoms Compared to A1 and A2 ß-Casein Milk in Lactose Maldigesters: A Two-Week Adaptation Study.

Approximately 30% of milk protein is ß-casein. We aimed to determine whether lactose maldigesters who chronically consumed two cups of A1/A2 milk (containing 75% A1 ß-casein and 25% A2 ß-casein) would adapt to have fewer intolerance symptoms, lower serum inflammatory markers, and/or altered glutathione levels similar to those consuming A2 milk (containing 100% A2 ß-casein). A double-blinded, randomized, crossover trial was conducted. Sixteen confirmed lactose maldigesters consumed 250 mL of A1/A2 milk and A2 milk twice daily with meals for two weeks. At the end of the adaptation period on day 15, lactose maldigestion was measured after a challenge with the same milk used for adaptation (0.5 g of lactose per kg of body weight) with a hydrogen breath test. Fecal urgency was higher during the two-week consumption of A1/A2 milk compared to A2 milk (p = 0.04, n = 16). Bloating (p = 0.03, n = 16) and flatulence (p = 0.02, n = 16) were also higher on the 15th day with A1/A2 milk compared to A2 milk challenge. However, day-to-day symptoms, hydrogen, serum inflammatory markers, and antioxidant concentrations were not different after A1/A2 and A2 milk consumption adaptation periods. Adaptation over two weeks did not improve lactose digestion or tolerance of A1/A2 milk to match that of A2 milk.

Anxiolytic-like effects of milk proteins.

Milk varieties and specific proteins exhibit anxiolytic-like actions in mice and rats exposed to several tests, the most prominent being the elevated plus-maze. Administrations of αs1-casein, its 91-100 (α-casozepine), 91-97, 91-93, and 91-92 fragments, the 60-69 fragment of ß-casein, lactoferrin, ß-lactotensin, wheylin-1, wheylin-2, and α-lactalbumin have been reported to increase open arm exploration relative to enclosed arm exploration. Anxiolytic-like actions have also been described for 91-93 and 91-92 fragments of αs1-casein, wheylin-1, α-lactalbumin, and lactoferrin in the open-field. Some effects appear to be mediated by the GABAA receptor complex, since antagonists mitigated the anxiolytic-like actions of αs1-casein, the 91-92 fragment of αs1-casein, and wheylin-1. Other neurotransmitters purported to affect such behaviors include 5HT, dopamine, and neurotensin. Further research is needed to identify their neuropharmacological actions.

Comparison of the Protective Effects of Casein Hydrolysate Containing Tyr-Pro-Val-Glu-Pro-Phe and Casein on the Behaviors and Peripheral and Brain Functions in Mice with Chronic-Stress-Induced Anxiety and Insomnia.

Chronic stress is a major inducer of anxiety and insomnia. Milk casein has been studied for its stress-relieving effects. We previously prepared a casein hydrolysate (CP) rich in the sleep-enhancing peptide YPVEPF, and this study aims to systemically investigate the different protective effects of CP and casein on dysfunction and anxiety/insomnia behavior and its underlying mechanisms in chronically stressed mice. Behavioral results showed that CP ameliorated stress-induced insomnia and anxiety more effectively than milk casein, and this difference in amelioration was highly correlated with an increase in GABA, 5-HT, GABAA, 5-HT1A receptors, and BDNF and a decrease in IL-6 and NMDA receptors in stressed mice. Furthermore, CP restored these dysfunctions in the brain and colon by activating the HPA response, modulating the ERK/CREB-BDNF-TrκB signaling pathway, and alleviating inflammation. The abundant YPVEPF (1.20 ± 0.04%) and Tyr-based/Trp-containing peptides of CP may be the key reasons for its different effects compared to casein. Thus, this work revealed the main active structures of CP and provided a novel dietary intervention strategy for the prevention and treatment of chronic-stress-induced dysfunction and anxiety/insomnia behaviors.

Exploring pectin-casein micelles as novel carriers for oral drug delivery of artesunate in the treatment of systemic lupus erythematosus.

The oral route of administration is considered the optimal choice for treating chronic diseases due to its convenience and non-invasiveness, which can help prevent physical and mental harm to patients undergoing long-term treatment. However, challenges such as safety, gastrointestinal stability, and bioavailability of oral drugs often limit their effectiveness. Natural biomacromolecule micelles, known for their safety, stability, biocompatibility, and diverse functions, have emerged as promising carriers for oral treatment of chronic diseases like systemic lupus erythematosus (SLE) with fat-soluble drugs. This study introduces an innovative approach by developing an oral delivery system using chemically synthesized natural biomacromolecules to load artesunate for treating SLE. By synthesizing amphiphilic polymer micelles from pectin and casein through a carbodiimide reaction, a more stable structure is achieved. The hydrophobic core of these micelles encapsulates artesunate, resulting in the formation of an oral delivery system (PC-AS) with several advantages, including high drug loading and encapsulation efficiency, small particle size, negative potential, strong stability in the gastrointestinal tract, low toxicity and side effects, strong adhesion in the small intestine, and high bioavailability. These advantages facilitate efficient absorption of artesunate in the gastrointestinal tract, leading to improved bioavailability and effective alleviation of SLE-like symptoms in MRL/lpr mice. By utilizing chemically synthesized natural macromolecular micelles for delivering artesunate in the treatment of SLE, this study overcomes the oral barriers associated with the original drug and presents a novel solution for the long-term oral treatment of chronic diseases.

Hemp seed protein and its hydrolysate compared with casein protein consumption in adults with hypertension: a double-blind crossover study.

BACKGROUND: The effects of consuming hemp seed protein (HSP) as well as its hydrolysate-derived bioactive peptide (HSP+) on blood pressure (BP) has not, to our knowledge, been investigated in humans. OBJECTIVES: We aimed to investigate how consumption of HSP and its hydrolysate modulates 24-h systolic (SBP) and diastolic BP (DBP) and plasma biomarkers of BP compared with casein. METHODS: In a double-blind, randomized, crossover design trial, 35 adults who had mild hypertension with SBP between 130 and 160 mmHg and DBP ≤110 mmHg were recruited. Participants were randomly assigned to varying sequences of 3 6-wk treatments, 50 g casein/d, 50 g HSP/d, or 45 g HSP plus 5 g HSP-derived bioactive peptides/d (HSP+), separated by a 2-wk washout period. Treatment effects were assessed with a linear mixed model with repeated measures. RESULTS: Compared with casein, after HSP+ consumption, 24-h SBP and 24-h DBP decreased from 135.1 and 80.0 mmHg to 128.1 ± 1.6 (P < 0.0001) and 76.0 ± 1.4 mmHg (P < 0.0001), respectively, whereas these values were 133.5 ± 1.6 and 78.9 ± 1.4 mmHg after HSP consumption (P < 0.0001). There were no differences between the HSP and HSP+ consumption in plasma angiotensin-converting enzyme (ACE) activity, renin, or nitric oxide (NO) concentrations. However, these 2 treatments were able to lower both ACE and renin activities and raise NO concentration in plasma compared with casein. CONCLUSIONS: These results suggest that hemp protein consumption, as well as in combination with bioactive peptides, may have a role in the dietary management of hypertension. This trial was registered at clinicaltrials.gov as NCT03508895.

Appetite, food intake, and gut hormone responses to glycomacropeptide protein ingestion in older adults: A feasibility, acceptability, and pilot study.

Glycomacropeptide (GMP) has a unique amino acid profile which may make less satiating than other dietary proteins. This study assessed the feasibility and likely acceptability of a leucine-enriched GMP drink and determined appetite response in older adults (OA). Thirteen OA (11f; 70 ± 4 years) were recruited for sensory assessments of a leucine-enriched GMP drink when mixed with water and with fruit smoothie, compared with whey protein isolate (WHEY). Participants also partook in a single focus group exploring acceptability to protein and supplementation. Separately, a counterbalanced, double-blind study with twelve OA (8f; 69 ± 3 years) was conducted to determine appetite and gut hormone responses. Fasting subjective appetite was recorded using visual analogue scales and a fasted venous blood sample was collected (to measures acyl-ghrelin, PYY, GLP-1, and CCK) before participants consumed either: GMP protein (27g + 3g leucine, 350 mL water), WHEY (30g, 350 mL water), or water. Participants rested for 240 min, with appetite measures and blood sampling throughout. An ad libitum pasta-based meal was then consumed. Sensory testing revealed low pleasantness rating for GMP in water vs. WHEY (16 ± 14 vs 31 ± 24, p = 0.016). GMP addition to smoothie reduced pleasantness (26 ± 21 vs. 61 ± 29, p = 0.009) and worsened the aroma (46 ± 15 vs. 69 ± 28, p = 0.014). The focus group revealed uncertainty of protein needs and a scepticism of supplements, with preference for food. Gut hormone response did not differ between GMP and WHEY (nAUC for all gut hormones p > 0.05). There was no difference between conditions for lunch ad libitum intake (549 ± 171 kcal, 512 ± 238 kcal, 460 ± 199 kcal for GMP, WHEY, and water, p = 0.175), or for subjective appetite response. Leucine-enriched GMP was not less satiating than WHEY, and low palatability and scepticism of supplements question the likely acceptability of GMP supplementation. Providing trusted nutritional advice and food enrichment/fortification may be preferred strategies for increasing protein intake in OA.

Immediate and sustained root caries prevention of fluoride varnish combined with toothpastes: findings of clinical relevance?

DESIGN: An in vitro study to determine the immediate and sustained effect of fluoride varnish and its combination with fluoride toothpastes in preventing the development of root caries. CASE SELECTION: Human root dentine samples (150) were randomly divided into five experimental protocols of 30 specimens each: 1) fluoride varnish (22,600 ppm fluoride and 1-5% CPP-ACP); 2) fluoride varnish followed by Paste One (1100 ppm sodium fluoride and CPP-ACP); 3) fluoride varnish followed by Paste Plus (900 ppm sodium fluoride and CPP-ACP); 4) fluoride varnish followed by Paste One and Paste Plus; and 5) no treatment (control). A layer of varnish was applied to specimens except the control group and was left in situ for 18 h. The varnish layer was removed, and the various toothpaste treatments were initiated. Half of the specimens in each group were assigned to a short-term incubation model in which they were immediately subjected to a 7-day cariogenic challenge consisting of a combination of human saliva and artificial saliva containing 2% sucrose. The other half of the specimens in each group were assigned to the long-term incubation model in which the experimental protocol was continued for 8 weeks before initiating the seven-day cariogenic challenge. The protocols were evaluated by assessing dentine porosity (rhodamine intensity), mineral density, biofilm biomass, and viability assays. DATA ANALYSIS: Confocal laser scanning microscopy was used to determine dentine porosity and Levene's test was used to verify the assumption of equality of variances and normal distribution of errors before two-way ANOVA and the Games-Howell test were carried out at a significance level of 0.05 for both incubation models. Microcomputed tomography was used to determine mineral density with statistical analysis involving Levene's test, two-way ANOVA and Tukey's test at a significance level of 0.05 for both incubation models. Biomass was evaluated using a biofilm biomass assay with analysis of optical density data using Levene's test, ANOVA and Scheffe's test at a significance level of 0.05. RESULTS: For both the short- and long-term incubation models, all the experimental regimes resulted in a statistically significant decrease in dentine porosity and an increase in mineral density when compared to the control group. Fluoride varnish followed by both pastes and fluoride varnish followed by Paste One resulted in a statistically significant decrease in dentine porosity for some depths in both models when compared to fluoride varnish alone. Changes in dentine porosity and mineral density were observed within groups over time. All the experimental regimes demonstrated anti-biofilm effects. Immediate and sustained anti-caries effects were observed for all preventive protocols, with the combination of fluoride varnish and Paste One resulting in superior additional anti-caries effects. CONCLUSIONS: The authors concluded that all protocols demonstrated immediate and sustained anti-caries effects against the development of root caries despite variations in effects over time. The combination of fluoride varnish and Paste One resulted in additional anti-caries effects that were consistently superior, with no additional effects being observed when Paste Plus was added in combination. The authors suggest that, within the study's limitations, topical fluoride varnish seems to have a protective effect on root surfaces for up to eight weeks and that fluoride varnish should be considered as an important adjunct strategy in the prevention of root caries in older adults.

Neonatal Gut and Immune Responses to ß-Casein Enriched Formula in Piglets.

BACKGROUND: ß-casein is the main casein constituent in human milk (HM) and a source of bioactive peptides for the developing gastrointestinal tract and immune system. Infant formulas contain less ß-casein than HM, but whether different concentrations of ß-casein affect tolerability and gut and immune maturation in newborns is unknown. OBJECTIVES: Using near-term piglets as a model for newborn infants, we investigated whether increasing the ß-casein fraction in bovine-based formula is clinically safe and may improve gut and immune maturation. METHODS: Three groups of near-term pigs (96% gestation) were fed formula with bovine casein and whey protein (ratio 40:60): 1) standard skim milk casein (BCN-standard, 35% ß-casein of total casein, n = 18); 2) ß-casein enrichment to HM concentrations (BCN-medium, 65%, n = 19); and 3) high ß-casein enrichment (BCN-high, 91%, n = 19). A reference group was fed 100% whey protein concentrate (WPC) as protein (WPC, n = 18). Intestinal and immune parameters were assessed before and after euthanasia on day 5. RESULTS: Clinical variables (mortality, activity, body growth, and diarrhea) were similar among the groups, and no differences in intestinal or biochemical parameters were observed between BCN-standard and BCN-medium pigs. However, pigs receiving high amounts of ß-casein (BCN-high) had lower small intestine weight and tended to have more intestinal complications (highest gut pathology score, permeability, and interleukin-8) than the other groups, particularly those receiving no casein (WPC pigs). Blood lymphocyte, thrombocyte, and reticulocyte counts were increased with higher ß-casein, whereas eosinophil counts were reduced. In vitro blood immune cell responses were similar among groups. CONCLUSIONS: ß-casein enrichment of bovine-based formula to HM concentrations is clinically safe, as judged from newborn, near-term pigs, whereas no additional benefits to gut maturation were observed. However, excessive ß-casein supplementation, beyond concentrations in HM, may potentially induce gut inflammation together with increased blood cell populations relative to natural ß-casein concentrations or pure whey-based formula.

Mice Regulate Dietary Amino Acid Balance and Energy Intake by Selecting between Complementary Protein Sources.

BACKGROUND: A balanced intake of protein and constituent amino acids (AAs) requires adjustments to total food intake (protein leverage [PL]) and food selection to balance deficits and excesses (complementary feeding). We provided mice with choices of casein and whey, 2 protein sources that are complementary in AA balance, across a range of protein concentrations (P%) of digestible energy (DE). OBJECTIVES: We aimed to determine if: 1) PL operates similarly for casein and whey; 2) one protein source is preferred at control P%; 3) the preference changes as P% falls; and 4) AA intakes under control and low P% levels identify AAs that drive changes in protein selection. METHODS: Food intake and plasma fibroblast growth factor-21 (FGF21) concentrations were measured in mice at various P% (P7.5%-P33%). For direct comparisons, defined diets were used in which the protein source was either casein or whey. In food choice studies, mice had access to foods in which both casein and whey were provided at the same P% level at the same time. RESULTS: PL operated at different P% thresholds in casein (13%)- and whey (10%)-based diets, and the magnitude of PL was greater for casein. Although mice preferred casein under control conditions (P23%), a pronounced preference shift to whey occurred as P% fell to P13% and P10%. At low P%, increases in food intake were accompanied by increases in plasma FGF21, a protein hunger signal. Among AAs deficient in casein and enriched in whey, the intake of Cys was the most invariant as P% changed between P23% and P10%, appearing to drive the switch in protein preference. CONCLUSIONS: Mice selected between complementary protein sources, casein and whey, achieving stable total energy intake and regulated intake of AAs as P% varied. Supplementation of low P% casein diets with one whey-enriched AA, Cys, suppressed plasma FGF21 and total food intake.

Preventive efficacy of 38% silver diamine fluoride and CPP-ACP fluoride varnish on molars affected by molar incisor hypomineralization in children: A randomized controlled trial.

Background: This randomized controlled trial aimed to compare the efficacy of silver diamine fluoride (SDF) and Casein Phosphopeptide-Amorphous Calcium Phosphate fluoride Varnish (CPP-ACPFV) in preventing caries development, enamel breakdown, and sensitivity on molars affected by molar incisor hypomineralization (MIH) in children. Methods: A total of 100 children aged 6 to 9 years were enrolled in the study with two contralateral permanent molars mildly affected by MIH. Affected molars were randomly and equally assigned to receive either SDF or CPP-ACPFV treatment. The interventions were applied at four different time points (baseline, 3, 6, 9 months), and the incidence of caries, caries progression, enamel breakdown, and sensitivity were assessed. Results: The findings of this study revealed significant differences in the incidence of caries between the groups treated with SDF and CPP-ACPFV ( P-value < 0.05). Similarly, there was a significant difference in caries progression between the two groups ( P-value < 0.05). However, no significant differences were observed in enamel breakdown scores between the treatment groups, as the majority of teeth in both groups exhibited a score of 0. Furthermore, there were no significant differences in sensitivity between the treatment groups throughout the study period. Conclusions: In conclusion, the results of this study provide evidence that molars treated with SDF demonstrated a lower incidence of caries and a higher rate of caries arrest compared to those treated with CPP-ACPFV. Both interventions showed promise in preventing enamel breakdown and improving sensitivity. These findings highlight the potential of SDF and CPP-ACPFV as effective treatments for caries prevention and management, emphasizing the importance of early intervention and appropriate dental care strategies in maintaining oral health. Trial registration: ISRCTN54243749 (13/01/2022).

Casein Glycomacropeptide: An Alternative Protein Substitute in Tyrosinemia Type I.

Tyrosinemia type I (HTI) is treated with nitisinone, a tyrosine (Tyr) and phenylalanine (Phe)-restricted diet, and supplemented with a Tyr/Phe-free protein substitute (PS). Casein glycomacropeptide (CGMP), a bioactive peptide, is an alternative protein source to traditional amino acids (L-AA). CGMP contains residual Tyr and Phe and requires supplementation with tryptophan, histidine, methionine, leucine, cysteine and arginine. AIMS: a 2-part study assessed: (1) the tolerance and acceptability of a low Tyr/Phe CGMP-based PS over 28 days, and (2) its long-term impact on metabolic control and growth over 12 months. METHODS: 11 children with HTI were recruited and given a low Tyr/Phe CGMP to supply all or part of their PS intake. At enrolment, weeks 1 and 4, caregivers completed a questionnaire on gastrointestinal symptoms, acceptability and ease of PS use. In study part 1, blood Tyr and Phe were assessed weekly; in part 2, weekly to fortnightly. In parts 1 and 2, weight and height were assessed at the study start and end. RESULTS: Nine of eleven children (82%), median age 15 years (range 8.6-17.7), took low Tyr/Phe CGMP PS over 28 days; it was continued for 12 months in n = 5 children. It was well accepted by 67% (n = 6/9), tolerated by 100% (n = 9/9) and improved gastrointestinal symptoms in 2 children. The median daily dose of protein equivalent from protein substitute was 60 g/day (range 45-60 g) with a median of 20 g/day (range 15 to 30 g) from natural protein. In part 2 (n = 5), a trend for improved blood Tyr was observed: 12 months pre-study, median Tyr was 490 µmol/L (range 200-600) and Phe 50 µmol/L (range 30-100); in the 12 months taking low Tyr/Phe CGMP PS, median Tyr was 430 µmol/L (range 270-940) and Phe 40 µmol/L (range 20-70). Normal height, weight and BMI z scores were maintained over 12 months. CONCLUSIONS: In HTI children, CGMP was well tolerated, with no deterioration in metabolic control or growth when studied over 12 months. The efficacy of CGMP in HTI needs further investigation to evaluate the longer-term impact on blood Phe concentrations and its potential influence on gut microflora.

Unveiling the Metabolic Effects of Glycomacropeptide.

For many years, the main nitrogen source for patients with phenylketonuria (PKU) was phenylalanine-free amino acid supplements. Recently, casein glycomacropeptide (GMP) supplements have been prescribed due to its functional and sensorial properties. Nevertheless, many doubts still persist about the metabolic effects of GMP compared to free amino acids (fAA) and intact proteins such as casein (CAS). We endeavour to compare, in rats, the metabolic effects of different nitrogen sources. Twenty-four male Wistar rats were fed equal energy density diets plus CAS (control, n = 8), fAA (n = 8) or GMP (n = 8) for 8 weeks. Food, liquid intake and body weight were measured weekly. Blood biochemical parameters and markers of glycidic metabolism were assessed. Glucagon-like peptide-1 (GLP-1) was analysed by ELISA and immunohistochemistry. Food intake was higher in rats fed CAS compared to fAA or GMP throughout the treatment period. Fluid intake was similar between rats fed fAA and GMP. Body weight was systematically lower in rats fed fAA and GMP compared to those fed CAS, and still, from week 4 onwards, there were differences between fAA and GMP. None of the treatments appeared to induce consistent changes in glycaemia, while insulin levels were significantly higher in GMP. Likewise, the production of GLP-1 was higher in rats fed GMP when compared to fAA. Decreased urea, total protein and triglycerides were seen both in fAA and GMP related to CAS. GMP also reduced albumin and triglycerides in comparison to CAS and fAA, respectively. The chronic consumption of the diets triggers different metabolic responses which may provide clues to further study potential underlying mechanisms.

Fast Anxiolytic-Like Effect Observed in the Rat Conditioned Defensive Burying Test, after a Single Oral Dose of Natural Protein Extract Products.

Anxiety appears among the most frequent psychiatric disorders. During recent years, a growing incidence of anxiety disorders can be attributed, at least in part, to the modification of our eating habits. To treat anxiety disorders, clinicians use benzodiazepines, which unfortunately display many side effects. Herein, the anxiolytic-like properties of two natural products (αS1-casein hydrolysate and Gabolysat®) were investigated in rats and compared to the efficacy of benzodiazepine (diazepam). Thus, the conditioned defensive burying test was performed after a unique oral dose of 15 mg/kg, at two time-points (60 min and then 30 min post oral gavage) to show potential fast-onset of anxiolytic effect. Both natural products proved to be as efficient as diazepam to reduce the time rats spent burying the probe (anxiety level). Additionally, when investigated as early as 30 min post oral gavage, Gabolysat® also revealed a fast-anxiolytic activity. To date, identification of bioactive peptide, as well as how they interact with the gut-brain axis to sustain such anxiolytic effect, still remains poorly understood. Regardless, this observational investigation argues for the consideration of natural compounds in care pathway.

Insulin- and cholic acid-loaded zein/casein-dextran nanoparticles enhance the oral absorption and hypoglycemic effect of insulin.

Diabetes mellitus is the most common metabolic disease in the world. Herein, insulin- and cholic acid-loaded zein nanoparticles with dextran surfaces were fabricated to enhance the oral absorptions of insulin in the intestine and in the liver which is the primary action organ of endogenous insulin. In the nanoparticles, zein acted as cement to embed insulin, cholic acid and casein by hydrophobic interactions. The hydrophilic dextran conjugated to casein by the Maillard reaction was located on the nanoparticle surface. The nanoparticles had an insulin loading efficiency of 74.6%, a cholic acid loading efficiency of 55.1% and a hydrodynamic diameter of 267 nm. The dextran significantly increased the disperse stability of the nanoparticles, protected the loaded insulin from hydrolysis in digestive juices, and increased the trans-mucus permeability of the insulin. The embedded cholic acid molecules were consecutively exposed to the surface when the nanoparticles were gradually eroded by proteases. The exposed cholic acid promoted the absorptions of the nanoparticles in the ileum and liver via bile acid transporters. The effect of pretreated lymphatic transport inhibitor cycloheximide revealed that about half of the nanoparticles were transported via the intestinal lymphatic transport pathway and the other half of the nanoparticles were transported via portal blood absorption. The oral pharmacological bioavailability of the nanoparticles in type I diabetic mice was 12.5-20.5%. This study demonstrates that nanoparticles are a promising oral delivery system for insulin.

Different Protein Sources in the Maternal Diet of the Rat during Gestation and Lactation Affect Milk Composition and Male Offspring Development during Adulthood.

Protein sources in maternal diet are important for mammary gland differentiation and milk protein; however, few studies have examined the metabolic and cellular adaptations of mothers based on protein source diets during pregnancy and lactation, and leptin concentration in offspring. We evaluated metabolic parameters and maternal key organs and milk components in mothers at the end of lactation, who were fed different sources of proteins. In postnatal day 110 and 250, we studied development parameters and leptin in male offspring. Female rats received a Vegetal (V) or Animal (A) diet during pregnancy and lactation. After weaning, male offspring ate V diet until postnatal day 250, which yielded two groups: Vv and Av. Milk dry, protein and fat were analyzed. Maternal metabolic parameters, leptin, and liver, adipose tissue and mammary gland histological analyses were studied. Body weight, food intake and leptin were analyzed in offspring at two ages. Adipose tissue weight and cells size and liver fat, mammary gland apoptosis, weight, milk protein and leptin were higher in A vs V. Maternal liver and milk dry were lower in A vs V. All offspring parameters were higher in Av vs Vv at postnatal day 110; however, at postnatal day 250, leptin was higher in Av vs Vv. Maternal serum and milk leptin had a positive correlation with offspring serum leptin at both ages. Consumption of animal protein-based diets by mothers during developmental periods affects specific maternal organs and changes milk composition during lactation, leading to a hyperleptinemic phenotype in male offsprings.

Methods to improve efficacy of orally administered bioactive peptides using bovine colostrum as an exemplar.

BACKGROUND: Oral administration of bioactive peptides has potential clinical advantages, but its applicability is limited due to gastric and pancreatic enzyme proteolysis. OBJECTIVE: To examine whether the co-packaging of bovine colostrum (BC), a rich source of IgG, immune and growth factors, with the food additives trehalose (carbohydrate), stearine (fat), casein (protein present in BC) or soy flour (plant based with high protease inhibitory activity) enhances the stability of BC against digestion. DESIGN: Samples alone and in combination (BC+ 10% wt/wt trehalose, stearine, casein or soy) were exposed to HCl/pepsin, followed by trypsin and chymotrypsin ("CT"). Assessment of proliferation used gastric AGS cells (Alamar blue), IgG function measured bovine IgG anti-E.coli binding and ELISAs quantified growth factor constituents. In vivo bioassay assessed ability of BC alone or with soy to reduce injury caused by dextran sodium sulphate (DSS, 4% in drinking water, 7 days, test products started 2 days prior to DSS). RESULTS: Proliferative activity of BC reduced 61% following HCl/pepsin and CT exposure. This was truncated 50% if soy was co-present, and also protected against loss of total IgG, IgG E.coli binding, TGFß, lactoferrin and EGF (all P<0.01 vs BC alone). Co-packaging with trehalose was ineffective in preventing digestion whereas casein or stearine provided some intermediate protective effects. Rats given BC alone showed beneficial effects on weight gain, disease activity index, tissue histology and colonic MPO. Soy alone was ineffective. BC+ soy combination showed the greatest benefit with a dose of 7 mg/kg (6.4 BC + 0.6 soy flour) having the same degree of benefit as using 20 mg/kg BC alone. CONCLUSION: Soy, and to a lesser extent casein, enhanced the biostability of BC against digestive enzymes. Co-packaging of BC with other food products such as soy flour could result in a decreased dose being required, improving cost-effectiveness and patient compliance.