Digestion of whey peptide induces antioxidant and anti-inflammatory bioactivity on glial cells: Sequences identification and structural activity analysis.

Whey derived peptides have shown potential activity improving brain function in pathological condition. However, there is little information about their mechanism of action on glial cells, which have important immune functions in brain. Astrocytes and microglia are essential in inflammatory and oxidative defense that take place in neurodegenerative disease. In this work we evaluate antioxidant and anti-inflammatory potential bioactivity of whey peptide in glial cells. Peptides were formed during simulated gastrointestinal digestion (Infogest protocol), and low molecular weight (<5kDA) peptides (WPHf) attenuated reactive oxygen species (ROS) production induced by hydrogen peroxide stimulus in both cells in dose-dependent manner. WPHf induced an increase in the antioxidant glutathione (GSH) content and prevented GSH reduction induced by lipopolysaccharides (LPS) stimulus in astrocytes cells in a cell specific form. An increase in cytokine mRNA expression (TNFα and IL6) and nitric oxide secretion induced by LPS was attenuated by WPHf pre-treatment in both cells. The inflammatory pathway was dependent on NFκB activation. Bioactive peptide ranking analysis showed positive correlation with hydrophobicity and negative correlation with high molecular weights. The sequence identification revealed 19 peptides cross-referred with bioactive database. Whey peptides were rich in leucine, valine and tyrosine in the C-terminal region and lysine in the N-terminal region. The anti-inflammatory and antioxidant potential of whey peptides were assessed in glia cells and its mechanisms of action were related, such as modulation of antioxidant enzymes and anti-inflammatory pathways. Features of the peptide structure, such as molecular size, hydrophobicity and types of amino acids present in the terminal region are associated to bioactivity.

Milk-derived antimicrobial peptides incorporated whey protein film as active coating to improve microbial stability of refrigerated soft cheese.

Nisin is the first FDA-approved antimicrobial peptide and shows significant antimicrobial activity against Gram-positive bacteria, but only a weakly inhibitory effect on Gram-negative bacteria. The aim of this study was to prepare whey protein-based edible films with the incorporation of milk-derived antimicrobial peptides (αs2-casein151-181 and αs2-casein182-207) and compare their mechanical properties and potential application in cheese packaging with films containing nisin. These two antimicrobial peptides showed similar activity against B. subtilis and much higher activity against E. coli than bacteriocin nisin, representing that these milk-derived peptides had great potential to be applied as food preservatives. Antimicrobial peptides in whey protein films caused an increase in film opaqueness and water vapor barrier properties but decreased the tensile strength and elongation at break. Compared to other films, the whey protein film containing αs2-casein151-181 had good stability in salt or acidic solution, as evidenced by the results from scanning electron microscope and Fourier transform infrared spectroscopy. Whey protein film incorporated with αs2-casein151-181 could inhibit the growth of yeasts and molds, and control the growth of psychrotrophic bacteria present originally in the soft cheese at refrigerated temperature. It also exhibited significant inhibitory activity against the development of mixed culture (E. coli and B. subtilis) in the cheese due to superficial contamination during storage. Antimicrobial peptides immobilized in whey protein films showed a higher effectiveness than their direct application in solution. In addition, films containing αs2-casein151-181 could act as a hurdle inhibiting the development of postprocessing contamination on the cheese surface during the 28 days of storage. The films in this study exhibited the characteristics desired for active packaging materials.

Enhanced probiotic viability in innovative double-network emulsion gels: Synergistic effects of the whey protein concentrate-xanthan gum complex and κ-carrageenan.

In this study, the whey protein concentrate and xanthan gum complex obtained by specific pH treatment, along with κ-carrageenan (KC), were used to encapsulate Lactobacillus acidophilus JYLA-191 in an emulsion gel system. The effects of crosslinking and KC concentration on the visual characteristics, stability, mechanical properties, and formation mechanism of emulsion gels were investigated. The results of optical imaging, particle size distribution, and rheology exhibited that with the addition of crosslinking agents, denser and more homogeneous emulsion gels were formed, along with a relative decrease in the droplet size and a gradual increase in viscosity. Especially when the concentration of citric acid (CA) was 0.09 wt%, KC was 0.8 wt%, and K+ was present in the system, the double-network emulsion gel was stable at high temperatures and in freezing environments, and the swelling ratio was the lowest (9.41%). Gastrointestinal tract digestive treatments and pasteurization revealed that the probiotics encapsulated in the double-network emulsion gel had a higher survival rate, which was attributed to the synergistic cross-linking of CA and K+ biopolymers to construct the emulsion gels. Overall, this study highlights the potential of emulsion gels to maintain probiotic vitality and provides valuable insights for developing inventive functional foods.

Short-time ozone treatment promotes protease-mediated destruction of B cell allergen epitopes by altering the structural characteristics of whey protein.

A novel processing method combining short-time ozone pretreatment with hydrolysis has been developed to reduce whey protein allergenicity. The results showed that ozone treatment altered the whey protein spatial structure, initially increasing the surface hydrophobicity index, and then decreasing due to polymer formation as the time increased. Under the optimized conditions of alkaline protease-mediated hydrolysis, a 10-second pre-exposure to ozone significantly promoted the reduction in the IgE binding capacity of whey protein without compromising the hydrolysis efficiency. Compared with whey protein, the degranulation of KU812 cells stimulated by this hydrolysate decreased by 20.54%, 17.99%, and 22.80% for IL-6, ß-hexosaminidase, and histamine, respectively. In vitro simulated gastrointestinal digestion confirmed increased digestibility and reduced allergenicity. Peptidomics identification revealed that short-time ozonation exposed allergen epitopes, allowing alkaline protease to target these epitopes more effectively, particularly those associated with α-lactalbumin. These findings suggest the promising application of this processing method in mitigating the allergenicity of whey protein.

Evaluation of the Effects of Whey Protein and Moringa Oleifera Leaves Extract Mixture on Osseointegration in Rabbits.

Background: Osteogenic, antioxidant and anti-inflammatory effects of Whey protein and M. oleifera gel prompted us to evaluate their role alone or in combination on osseointegration in rabbits. Methods: In this study, 24 titanium implants were inserted in the femurs of six rabbits. One implant was placed without treatment, and another one was coated with a mixture of whey protein and M. oleifera gel for each side. The animals were divided into two groups of 2- and 6-week intervals and evaluated using histopathological and immunohistochemical techniques. Results: Histological evaluation revealed a significant difference between the experimental and the control groups after two weeks in osteoblast and osteocyte counts. The experimental group had mature bone development after six weeks of implantation, while the control group had a woven bone. Immunohistochemical results showed that the experimental group, compared to the control group, exhibited early positive expression of osteoblast cells at two weeks after the experiment. Based on histopathological observations, the experimental group showed a tiny area of collagenous fiber in 6th week after the implantation. Conclusion: A mixture of whey protein and M. oleifera could accelerate osseointegration and healing processes.

Exploring animal protein sources against prevent age-related short-term memory decline in mice: Dietary fish (Alaska Pollock) protein exhibits superior protective effects.

Dietary factors, particularly proteins, have been extensively explored to combat cognitive impairment. We have previously reported that dietary fish (Alaska Pollock) protein (APP) is more effective than casein (CAS) or fish oil in maintaining short-term memory in senescence-accelerated mice prone 10 (SAMP10). To examine the specificity of the protective effect of APP intakes against short-term memory decline, we assessed the impact of various dietary animal proteins, including APP, CAS, chicken breast protein (CP), and whey protein (WP), against age-related cognitive function in SAMP10 mice. After feeding the experimental diets for 5 months, memory was assessed using the Y-maze. The APP group exhibited a significant increase in spontaneous alternation behavior as an indicator of working memory when group compared with groups fed with other protein source. Additionally, the APP group displayed significantly higher neurofilament heavy chain positivity than the CAS and CP groups, as evidenced immunohistochemical analysis. Gut microbiota analysis indicated that dietary APP significantly enhanced the relative abundance of Lactobacillus, which positively correlated with spontaneous alternation behavior. Collectively, these findings suggest that dietary APP is more effective than CAS, CP, or WP in preventing age-related short-term memory decline and morphological abnormalities in the hippocampal axons of SAMP10 mice. Moreover, APP-mediated improvements in cognitive deficits may be associated with changes in microbiota diversity. PRACTICAL APPLICATION: This research suggests that dietary fish protein from Alaska Pollock may be more efficient in prevention short-term memory decline in mice, compared to other animal proteins. This finding has practical implications for nutritional optimization, developing the new health food products, and elucidating the relationship between the impact of specific proteins on gut microbiota and prevention of age-related cognitive decline.

Both live and heat killed Lactiplantibacillus plantarum DPUL-F232 alleviate whey protein-induced food allergy by regulating cellular immunity and repairing the intestinal barrier.

Postbiotics have been proposed as clinically viable alternatives to probiotics, addressing limitations and safety concerns associated with probiotic use. However, direct comparisons between the functional differences and health benefits of probiotics and postbiotics remain scarce. This study compared directly the desensitization effect of probiotics and postbiotics derived from Lactiplantibacillus plantarum strain DPUL-F232 in the whey protein-induced allergic rat model. The results demonstrate that administering both live and heat killed F232 significantly alleviated allergy symptoms, reduced intestinal inflammation, and decreased serum antibody and histamine levels in rats. Both forms of F232 were effective in regulating the Th1/Th2 balance, promoting the secretion of the regulatory cytokine IL-10, inhibiting mast cell degranulation and restoring the integrity of the intestinal barrier through the upregulation of tight junction proteins. Considering the enhanced stability and reduced safety concerns of postbiotics compared to probiotics, alongside their ability to regulate allergic reactions, we suggest that postbiotics may serve as viable substitutes for probiotics in managing food allergies and potentially other diseases.

Readily Available Oral Prebiotic Protein Reactive Oxygen Species Nanoscavengers for Synergistic Therapy of Inflammation and Fibrosis in Inflammatory Bowel Disease.

A significant gap exists in the demand for safe and effective drugs for inflammatory bowel disease (IBD), and its associated intestinal fibrosis. As oxidative stress plays a central role in the pathogenesis of IBD, astaxanthin (AST), a good antioxidant with high safety, holds promise for treating IBD. However, the application of AST is restricted by its poor solubility and easy oxidation. Herein, different protein-based nanoparticles (NPs) are fabricated for AST loading to identify an oral nanovehicle with potential clinical applicability. Through systematic validation via molecular dynamics simulation and in vitro characterization of properties, whey protein isolate (WPI)-driven NPs using a simple preparation method without the need for cross-linking agents or emulsifiers were identified as the optimal carrier for oral AST delivery. Upon oral administration, the WPI-driven NPs, benefiting from the intrinsic pH sensitivity and mucoadhesive properties, effectively shielded AST from degradation by gastric juices and targeted release of AST at intestinal lesion sites. Additionally, the AST NPs displayed potent therapeutic efficacy in both dextran sulfate sodium (DSS)-induced acute colitis and chronic colitis-associated intestinal fibrosis by ameliorating inflammation, oxidative damage, and intestinal microecology. In conclusion, the AST WPI NPs hold a potential therapeutic value in treating inflammation and fibrosis in IBD.

Fucoidan alleviates the inhibition of protein digestion by chitosan and its oligosaccharides.

Chitosan (CTS) and chitosan oligosaccharides (COS) have been widely applied in food industry due to their bioactivities and functions. However, CTS and COS with positive charges could interact with proteins, such as whey protein isolate (WPI), influencing their digestion. Interaction among CTS/COS, FUC, and WPI/enzymes was studied by spectroscopy, chromatography, and chemical methods in order to reveal the role of FUC in relieving the inhibition of protein digestibility by CTS/COS and demonstrate the action mechanisms. As shown by the results, the addition of FUC increased degree of hydrolysis (DH) and free protein in the mixture of CTS and WPI to 3.1-fold and 1.8-fold, respectively, while raise DH value and free protein in the mixture of COS and WPI to 6.7-fold and 1.2-fold, respectively. The interaction between amino, carboxyl, sulfate, and hydroxyl groups from carbohydrates and protein could be observed, and notably, FUC could interact with CTS/COS preferentially to prevent CTS/COS from combining with WPI. In addition, the addition of FUC could also relieve the combination of CTS to trypsin, increasing the fluorescence intensity and concentration of trypsin by 83.3 % and 4.8 %, respectively. Thus, the present study demonstrated that FUC could alleviate the inhibitory effect of CTS/COS on protein digestion.

Acute effects of a ketone monoester, whey protein, or their coingestion on mTOR trafficking and protein-protein colocalization in human skeletal muscle.

We recently demonstrated that acute oral ketone monoester intake induces a stimulation of postprandial myofibrillar protein synthesis rates comparable to that elicited following the ingestion of 10 g whey protein or their coingestion. The present investigation aimed to determine the acute effects of ingesting a ketone monoester, whey protein, or their coingestion on mechanistic target of rapamycin (mTOR)-related protein-protein colocalization and intracellular trafficking in human skeletal muscle. In a randomized, double-blind, parallel group design, 36 healthy recreationally active young males (age: 24.2 ± 4.1 yr) ingested either: 1) 0.36 g·kg-1 bodyweight of the ketone monoester (R)-3-hydroxybutyl (R)-3-hydroxybutyrate (KET), 2) 10 g whey protein (PRO), or 3) the combination of both (KET + PRO). Muscle biopsies were obtained in the overnight postabsorptive state (basal conditions), and at 120 and 300 min in the postprandial period for immunofluorescence assessment of protein translocation and colocalization of mTOR-related signaling molecules. All treatments resulted in a significant (Interaction: P < 0.0001) decrease in tuberous sclerosis complex 2 (TSC2)-Ras homolog enriched in brain (Rheb) colocalization at 120 min versus basal; however, the decrease was sustained at 300 min versus basal (P < 0.0001) only in KET + PRO. PRO and KET + PRO increased (Interaction: P < 0.0001) mTOR-Rheb colocalization at 120 min versus basal; however, KET + PRO resulted in a sustained increase in mTOR-Rheb colocalization at 300 min that was greater than KET and PRO. Treatment intake increased mTOR-wheat germ agglutinin (WGA) colocalization at 120 and 300 min (Time: P = 0.0031), suggesting translocation toward the fiber periphery. These findings demonstrate that ketone monoester intake can influence the spatial mechanisms involved in the regulation of mTORC1 in human skeletal muscle.NEW & NOTEWORTHY We explored the effects of a ketone monoester (KET), whey protein (PRO), or their coingestion (KET + PRO) on mTOR-related protein-protein colocalization and intracellular trafficking in human muscle. All treatments decreased TSC2-Rheb colocalization at 120 minutes; however, KET + PRO sustained the decrease at 300 min. Only PRO and KET + PRO increased mTOR-Rheb colocalization; however, the increase at 300 min was greater in KET + PRO. Treatment intake increased mTOR-WGA colocalization, suggesting translocation to the fiber periphery. Ketone bodies influence the spatial regulation of mTOR.

Whey protein supplementation reduced the liver damage scores of rats fed with a high fat-high fructose diet.

Different functional foods with bioactive nutrients are being explored for the management of NAFLD. Whey proteins are rich in bioactive peptides and are suggested to show antioxidant and anti-inflammatory effects. We aim to test the hypothesis that the whey protein supplementation following a high fat-high fructose (HFHF) diet would protect against liver damage, inflammation, endotoxemia and steatosis in male Wistar rats. 36 rats were randomized into four groups for 8 weeks as the HFHF diet group, HFHF diet and whey protein isolate (WPI-200mg/kg/day) group (HFHF+WPI), control (C) group, and C+WPI (200mg/kg/day) group. Rats fed with a HFHF diet had higher final body weight compared to C and C+WPI groups (p = 0.002). Thus, WPI showed no significant effects for the body weight of rats with a HFHF diet. On the other hand, the HFHF+WPI group had significantly lower abdominal circumference when compared with the HFHF group (p<0,001). Higher serum CRP levels were observed in the groups with a HFHF diet (p<0,001) and WPI supplementation showed no effects on CRP levels. Whey protein supplementation resulted with lower total liver damage score in HFHF+WPI group compared with the HFHF diet group (p<0,001). Conversely, higher liver damage scores were observed with the C+WPI group compared to C group (p<0,001). HFHF diet resulted with higher expression of TLR-4 in the liver meanwhile WPI supplementation showed no effects on liver TLR-4 expression. We observed higher colon Occludin expression in HFHF+WPI and C+WPI groups compared with HFHF and C groups (p<0,001). Our results showed that, whey protein supplementation might help improve liver damage associated with a high fat-high fructose diet and increase the expression of Occludin in the small intestine and colon.

Dietary Intervention with Whey Protein Concentrate Does Not Affect Toll-like Receptor Responses and Gene Expression Patterns in Peripheral Blood Mononuclear Cells of Healthy Volunteers.

Bovine milk contains bioactive proteins, carbohydrates, and phospholipids with immunomodulatory properties impacting human immunity, potentially contributing to resistance to infections and allergies through diverse mechanisms. One such mechanism is the enhancing of the innate immune response to secondary pathogen-related stimuli, termed innate immune training. Although in vitro studies demonstrate that milk immunoglobulin G (IgG) can train human monocytes, evidence for in vivo immune training is limited. To explore the potential of bovine IgG for inducing innate immune training in vivo, this human study utilized an IgG-rich whey protein concentrate (WPC). Healthy male volunteers were assigned to a high dose WPC, low dose WPC, or placebo group. Blood was collected pre- and post-two weeks of WPC consumption. Peripheral blood mononuclear cells (PBMCs) were isolated and stimulated with TLR ligands, evaluating IL-6 and TNF-α production by monocytes, myeloid DCs, and plasmacytoid DCs. Additionally, RNA was isolated for differential gene expression (DGE) analysis. Results indicated that the two-week WPC intervention did not influence the ex vivo response of studied cells to TLR agonists. Furthermore, PBMC gene expression patterns showed no significant differences between the placebo and high dose WPC groups. The data suggests that oral WPC ingestion did not enhance immune responses in young, healthy male participants.

Sustainable whey proteins-nanostructured zinc oxide-based films for the treatment of chronic wounds: New insights from biopharmaceutical studies.

Chronic wounds represent silent epidemic affecting a large portion of the world population, especially the elders; in this context, the development of advanced bioactive dressings is imperative to accelerate wound healing process, while contrasting or preventing infections. The aim of the present work was to provide a deep characterization of the functional and biopharmaceutical properties of a sustainable thin and flexible films, composed of whey proteins alone (WPI) and added with nanostructured zinc oxide (WPZ) and intended for the management of chronic wounds. The potential of whey proteins-based films as wound dressings has been confirmed by their wettability, hydration properties, elastic behavior upon hydration, biodegradation propensity and, when added with nanostructured zinc oxide, antibacterial efficacy against both Gram-positive and Gram-negative pathogens, i.e. Staphylococcus aureus and Escherichia coli. In-vitro experiments, performed on normal human dermal fibroblasts, confirmed film cytocompatibility, also revealing the possible role of Zn2+ ions in promoting fibroblast proliferation. Finally, in-vivo studies on rat model confirmed film suitability to act as wound dressing, since able to ensure a regular healing process while providing effective protection from infections. In particular, both films WPI and WPZ are responsible for the formation in the wound bed of a continuous collagen layer similar to that of healthy skin.

Antirotaviral activity of dairy byproducts enriched in fractions from hyperimmune bovine colostrum: the effect of thermal and high hydrostatic pressure treatments.

Nowadays, rotaviruses remain a major health burden, especially in developing countries, and strategies complementary to vaccination are needed. In this view, dairy fractions have attracted great scientific interest, due to their high content of bioactive compounds. The objective of this study was to evaluate the antiviral activity of whey and buttermilk enriched in proteins from hyperimmune bovine colostrum (HBC) against rotavirus. The enriched fractions were spray-dried and subsequently tested for their neutralizing activity against the bovine rotavirus WC3 strain in vitro, using differentiated Caco-2/TC7 cells. The highest antirotaviral activity was observed when whey and buttermilk were enriched in purified immunoglobulin G (IgG), showing complete rotavirus neutralization at concentrations of 3 and 6 mg mL-1 for whey and buttermilk, respectively. Additionally, the use of a crude immunoglobulin fraction also gave satisfactory results. The inhibitory activities of all samples significantly decreased after the application of heat, except for the IgG-enriched buttermilk which showed a slight increase of activity following the application of short-time treatments (75 or 85 °C for 20 s). This sample also showed a significant increase of activity (13%) after the application of low-intensity high hydrostatic pressure treatment (400 MPa for 5 min). The maximum loss of bioactivity was observed at 600 MPa for 10 min (31 and 20% for whey- and buttermilk-based formulas, respectively). This study provides relevant information on the potential of whey, buttermilk, and HBC to be part of functional products as complementary strategies to combat rotavirus infections.

The Effects of Yeast Protein on Gut Microbiota in Mice When Compared with Soybean Protein and Whey Protein Isolates.

Different protein sources can impact gut microbiota composition and abundance, and also participate in health regulation. In this study, mice were gavaged with yeast protein (YP), soybean protein isolate (SPI), and whey protein isolate (WPI) for 28 days. Body weights showed similar patterns across different protein administration groups. The ileum in YP-supplemented mice exhibited good morphology, and tight-junction (TJ) proteins were slightly upregulated. Immunoglobulin (Ig)A, IgM, and IgG levels in the ileum of different protein groups were significantly increased (p < 0.05). Interleukin (IL)-10 levels were significantly increased, whereas IL-6 levels were significantly reduced in the YP group when compared with the control (C) (p < 0.05). Glutathione peroxidase (GSH-Px) levels in the ileum were significantly increased in the YP group (p < 0.05). These results indicate that YP potentially improved intestinal immunity and inflammatory profiles. The relative abundances of Parabacteroides, Prevotella, and Pseudobutyrivibrio in the YP group were more enriched when compared with the C and SPI groups, and Parabacteroides was significantly upregulated when compared with the WPI group (p < 0.05). Overall, the results indicate that YP upregulates the beneficial bacteria and improves ileal immunity and anti-inflammatory capabilities.

Synergistic effects of MFG-E8 and whey protein on mitigating d-galactose-induced sarcopenia through PI3K/AKT/PGC-1α and MAPK/ERK signaling pathways.

Milk fat globule epidermal growth factor 8 (MFG-E8) and whey protein have emerged as promising bionutrient supplements for enhancing skeletal muscle mass and function. In the present study, aging-related sarcopenia rat model was employed to elucidate the effects of the combined administration of MFG-E8 and whey protein on the catabolism and anabolism of gastrocnemius protein. Combined intervention led to notable enhancements in the antioxidative stress status and mitochondrial biogenesis capacity of gastrocnemius muscle fibers in the aging rats, concomitant with a significant inhibition of lipid accumulation. Moreover, the synergistic effect of MFG-E8 and whey protein was found to exert modulatory effects on key signaling pathways, including PI3K/Akt/PGC-1α pathway and MAPK/ERK signaling pathways in the gastrocnemius muscle of the aging rats. Specifically, this combined intervention was observed to promote mitochondrial biogenesis and regulate the expression of protein anabolism and catabolism-related regulators, thereby facilitating the alleviation of mitochondrial oxidative stress and enhancing biogenesis in gastrocnemius tissues. The findings of our study provide compelling evidence for the potential of MFG-E8 as a promising dietary supplement with antisarcopenic properties to ameliorate muscle protein metabolism disorders and mitigate mitochondrial-mediated myoblast apoptosis induced by oxidative stress.

Partly Substituting Whey for Collagen Peptide Supplementation Improves Neither Indices of Muscle Damage Nor Recovery of Functional Capacity During Eccentric Exercise Training in Fit Males.

Previous studies showed that collagen peptide supplementation along with resistance exercise enhance muscular recovery and function. Yet, the efficacy of collagen peptide supplementation in addition to standard nutritional practices in athletes remains unclear. Therefore, the objective of the study was to compare the effects of combined collagen peptide (20 g) and whey protein (25 g) supplementation with a similar daily protein dose (45 g) of whey protein alone on indices of muscle damage and recovery of muscular performance during eccentric exercise training. Young fit males participated in a 3-week training period involving unilateral eccentric exercises for the knee extensors. According to a double-blind, randomized, parallel-group design, before and after training, they received either whey protein (n = 11) or whey protein + collagen peptides (n = 11). Forty-eight hours after the first training session, maximal voluntary isometric and dynamic contraction of the knee extensors were transiently impaired by ∼10% (Ptime < .001) in whey protein and whey protein + collagen peptides, while creatine kinase levels were doubled in both groups (Ptime < .01). Furthermore, the training intervention improved countermovement jump performance and maximal voluntary dynamic contraction by respectively 8% and 10% (Ptime < .01) and increased serum procollagen type 1N-terminal peptide concentration by 10% (Ptime < .01). However, no differences were found for any of the outcomes between whey and whey protein + collagen peptides. In conclusion, substituting a portion of whey protein for collagen peptide, within a similar total protein dose, improved neither indices of eccentric muscle damage nor functional outcomes during eccentric training.

Effects of Whey Protein Combined with Amylopectin/Chromium on the Muscle Protein Synthesis and mTOR Phosphorylation in Exercised Rats.

This study aimed to examine the impact of varying doses of whey protein (WP) and amylopectin/chromium complex (ACr) supplementation on muscle protein synthesis (MPS), amino acid and insulin levels, and the rapamycin (mTOR) signaling pathways in exercised rats. A total of 72 rats were randomly divided into nine groups: (1) Exercise (Ex), (2) Ex + WPI to (5) Ex + WPIV with various oral doses of whey protein (0.465, 1.55, 2.33, and 3.1 g/kg) and (6) Ex + WPI + ACr to (9) Ex + WPIV + ACr with various doses of whey protein combined with 0.155 g/kg ACr. On the day of single-dose administration, the products were given by oral gavage after exercise. To measure the protein fractional synthesis rate (FSR), a bolus dose of deuterium-labeled phenylalanine was given, and its effects were evaluated 1 h after supplementation. Rats that received 3.1 g/kg of whey protein (WP) combined with ACr exhibited the most significant increase in muscle protein synthesis (MPS) compared to the Ex group (115.7%, p < 0.0001). In comparison to rats that received the same dose of WP alone, those given the combination of WP and ACr at the same dosage showed a 14.3% increase in MPS (p < 0.0001). Furthermore, the WP (3.1 g/kg) + ACr group exhibited the highest elevation in serum insulin levels when compared to the Ex group (111.9%, p < 0.0001). Among the different groups, the WP (2.33 g/kg) + ACr group demonstrated the greatest increase in mTOR levels (224.2%, p < 0.0001). Additionally, the combination of WP (2.33 g/kg) and ACr resulted in a 169.8% increase in 4E-BP1 levels (p < 0.0001), while S6K1 levels rose by 141.2% in the WP (2.33 g/kg) + ACr group (p < 0.0001). Overall, supplementation with various doses of WP combined with ACr increased MPS and enhanced the mTOR signaling pathway compared to WP alone and the Ex group.

Grass-Fed and Non-Grass-Fed Whey Protein Consumption Do Not Attenuate Exercise-Induced Muscle Damage and Soreness in Resistance-Trained Individuals: A Randomized, Placebo-Controlled Trial.

Eccentric muscle contractions can cause structural damage to muscle cells resulting in temporarily decreased muscle force production and soreness. Prior work indicates pasture-raised dairy products from grass-fed cows have greater anti-inflammatory and antioxidant properties compared to grain-fed counterparts. However, limited research has evaluated the utility of whey protein from pasture-raised, grass-fed cows to enhance recovery compared to whey protein from non-grass-fed cows. Therefore, using a randomized, placebo-controlled design, we compared the effect of whey protein from pasture-raised, grass-fed cows (PRWP) to conventional whey protein (CWP) supplementation on indirect markers of muscle damage in response to eccentric exercise-induced muscle damage (EIMD) in resistance-trained individuals. Thirty-nine subjects (PRWP, n = 14; CWP, n = 12) completed an eccentric squat protocol to induce EIMD with measurements performed at 24, 48, and 72 h of recovery. Dependent variables included: delayed onset muscle soreness (DOMS), urinary titin, maximal isometric voluntary contraction (MIVC), potentiated quadriceps twitch force, countermovement jump (CMJ), and barbell back squat velocity (BBSV). Between-condition comparisons did not reveal any significant differences (p ≤ 0.05) in markers of EIMD via DOMS, urinary titin, MIVC, potentiated quadriceps twitch force, CMJ, or BBSV. In conclusion, neither PRWP nor CWP attenuate indirect markers of muscle damage and soreness following eccentric exercise in resistance-trained individuals.

Macrophage-Immunomodulatory Actions of Bovine Whey Protein Isolate, Glycomacropeptide, and Their In Vitro and In Vivo Digests.

Whey protein isolate (WPI) consists of an array of proteins and peptides obtained as a byproduct of the cheesemaking process. Research suggests that WPI, along with its peptides such as glycomacropeptide (GMP), possesses immunomodulatory properties. These properties hold potential for alleviating the adverse effects of inflammatory conditions such as inflammatory bowel disease. Although promising, the immunoregulatory properties of the digested forms of WPI and GMP-those most likely to interact with the gut immune system-remain under-investigated. To address this knowledge gap, the current study examined the effects of in vitro-digested WPI and GMP, in vivo-digested WPI, and undigested WPI and GMP on the secretion of pro-inflammatory cytokines (TNF-α and IL-1ß) in lipopolysaccharide-stimulated macrophage-like cells. Our results indicate that digested WPI and GMP reduced the expression of TNF-α and IL-1ß, two pro-inflammatory cytokines. Whole WPI had no effect on TNF-α but reduced IL-1ß levels. In contrast, in vivo-digested WPI reduced TNF-α but increased IL-1ß. Undigested GMP, on the other hand, increased the secretion of both cytokines. These results demonstrate that digestion greatly modifies the effects of WPI and GMP on macrophages and suggest that digested WPI and GMP could help mitigate gastrointestinal inflammation. Further clinical studies are necessary to determine the biological relevance of WPI and GMP digestion products within the gut and their capacity to influence gut inflammation.