Camel milk protein hydrosylate alleviates hepatic steatosis and hypertension in high fructose-fed rats

CONTEXT

Camel milk is used in traditional medicine to treat diabetes mellitus hypertension and other metabolic disorders.

OBJECTIVE

This study evaluated the antisteatotic and antihypertensive effects of camel milk protein hydrolysate (CMH) in high fructose (HF)-fed rats and compared it with the effects afforded by the intact camel milk protein extract (ICM).

MATERIALS AND METHODS

Adult male Wistar rats were divided into 6 groups (n = 8 each) as 1) control, 2) ICM (1000 mg/kg), 3) CMH (1000 mg/kg), 4) HF (15% in drinking water), 5) HF (15%) + ICM (1000 mg/kg), and 6) HF (15%) + CMH (1000 mg/kg). All treatments were given orally for 21 weeks, daily.

RESULTS

Both ICM and CMH reduced fasting glucose and insulin levels, serum and hepatic levels of cholesterol and triglycerides, and serum levels of ALT and AST, angiotensin II, ACE, endothelin-1, and uric acid in HF-fed rats. In addition, both ICM and CMH reduced hepatic fat deposition in the hepatocytes and reduced hepatocyte damage. This was associated with an increase in the hepatic activity of AMPK, higher PPARα mRNA, reduced expression of fructokinase C, SREBP1, SREBP2, fatty acid synthase, and HMG-CoA-reductase. Both treatments lowered systolic and diastolic blood pressure. However, the effects of CMH on all these parameters were greater as compared to ICM.

DISCUSSION AND CONCLUSIONS

The findings of this study encourage the use of CMH in a large-scale population and clinical studies to treat metabolic steatosis and hypertension.

Potential Protective Protein Components of Cow's Milk against Certain Tumor Entities

Milk and dairy products, especially from cow's milk, play a major role in the daily human diet. It is therefore hardly surprising that the subject of milk is being extensively researched and that many effects of individual milk components have been characterized as a result. With the wealth of results available today, the influence of milk on the development of various types of cancer and, in particular, its often protective effects have been shown both in vitro and in vivo and in the evaluation of large-scale cohort and case-control studies. Various caseins, diverse whey proteins such as α-lactalbumin (α-LA), bovine α-lactalbumin made lethal to tumor cells (BAMLET), β-lactoglobulin (β-LG), or bovine serum albumin (BSA), and numerous milk fat components, such as conjugated linoleic acid (CLA), milk fat globule membrane (MFGM), or butyrate, as well as calcium and other protein components such as lactoferrin (Lf), lactoferricin (Lfcin), and casomorphines, show antitumor or cytotoxic effects on cells from different tumor entities. With regard to a balanced and health-promoting diet, milk consumption plays a major role in a global context. This work provides an overview of what is known about the antitumoral properties of proteins derived from cow's milk and their modes of action.

The Impact of Protein Supplementation on Exercise-Induced Muscle Damage, Soreness and Fatigue Following Prolonged Walking Exercise in Vital Older Adults: A Randomized Double-Blind Placebo-Controlled Trial

Background: It is unknown whether protein supplementation can enhance recovery of exercise-induced muscle damage in older adults who have a disturbed muscle protein synthetic response. We assessed whether protein supplementation could attenuate exercise-induced muscle damage and soreness after prolonged moderate-intensity walking exercise in older adults. Methods: In a double-blind, placebo-controlled intervention study, 104 subjects (81% male, ≥65 years) used either a protein (n = 50) or placebo supplement (n = 54) during breakfast and directly after exercise. Within a walking event, study subjects walked 30/40/50 km per day on three consecutive days. Muscle soreness and fatigue were determined with a numeric rating scale, and creatine kinase (CK) concentrations and serum inflammation markers were obtained. Results: Habitual protein intake was comparable between the protein (0.92 ± 0.27 g/kg/d) and placebo group (0.97 ± 0.23 g/kg/d, p = 0.31). At baseline, comparable CK concentrations were found between the protein and the placebo group (110 (IQR: 84–160 U/L) and 115 (IQR: 91–186 U/L), respectively, p = 0.84). Prolonged walking (protein: 32 ± 9 km/d, placebo: 33 ± 6 km/d) resulted in a cumulative increase of CK in both the protein (∆283 (IQR: 182–662 U/L)) and placebo group (∆456 (IQR: 209–885 U/L)) after three days. CK elevations were not significantly different between groups (p = 0.43). Similarly, no differences in inflammation markers, muscle soreness and fatigue were found between groups. Conclusions: Protein supplementation does not attenuate exercise-induced muscle damage, muscle soreness or fatigue in older adults performing prolonged moderate-intensity walking exercise.

Sources, Production, and Clinical Treatments of Milk Fat Globule Membrane for Infant Nutrition and Well-Being

Research on milk fat globule membrane (MFGM) is gaining traction. The interest is two-fold; on the one hand, it is a unique trilayer structure with specific secretory function. On the other hand, it is the basis for ingredients with the presence of phospho- and sphingolipids and glycoproteins, which are being used as food ingredients with valuable functionality, in particular, for use as a supplement in infant nutrition. This last application is at the center of this Review, which aims to contribute to understanding MFGM's function in the proper development of immunity, cognition, and intestinal trophism, in addition to other potential effects such as prevention of diseases including cardiovascular disease, impaired bone turnover and inflammation, skin conditions, and infections as well as age-associated cognitive decline and muscle loss. The phospholipid composition of MFGM from bovine milk is quite like human milk and, although there are some differences due to dairy processing, these do not result in a chemical change. The MFGM ingredients, as used to improve the formulation in different clinical studies, have indeed increased the presence of phospholipids, sphingolipids, glycolipids, and glycoproteins with the resulting benefits of different outcomes (especially immune and cognitive outcomes) with no reported adverse effects. Nevertheless, the precise mechanism(s) of action of MFGM remain to be elucidated and further basic investigation is warranted.

Milk in the prevention and management of type 2 diabetes: The potential role of milk proteins

Globally, diabetes mellitus is not only considered a leading cause of mortality and morbidities but has also created a substantial economic burden. There is growing evidence that foods and their components can be implemented in the prevention and management of type 2 diabetes mellitus (T2DM). Increased dairy consumption has been linked to a lower risk of T2DM. The protective role of dairy foods in the development of T2DM is thought to be largely attributable to dairy nutrients, one of them being dairy protein. There is considerable evidence that milk proteins increase the postprandial insulin response and lower the postprandial blood glucose response in both healthy subjects and patients with T2DM. The exact mechanisms by which milk proteins lower postprandial glucose levels are yet to established; however, the amino acids and bioactive peptides derived from milk proteins are thought to modify a physiological milieu, which includes delayed gastric emptying and the enhancement of incretin and insulin responses, consequently leading to lower postprandial glucose levels. The present review will focus on providing a clear presentation of the potential implementation of milk proteins as a dietary supplement in the prevention and management of T2DM by summarizing the relevant supporting evidence for this particular topic.

Development and Characterization of Whey Protein-Based Nano-Delivery Systems: A Review

Various bioactive compounds (BCs) often possess poor stability and bioavailability, which makes it difficult for them to exert their potential health benefits. These limitations can be countered by the use of nano-delivery systems (NDSs), such as nanoparticles and nanoemulsions. NDSs can protect BCs against harsh environments during food processing and digestion, and thereby, could enhance the bioavailability of BCs. Although various NDSs have been successfully produced with both synthetic and natural materials, it is necessary to fulfill safety criteria in the delivery materials for food applications. Food-grade materials for the production of NDSs, such as milk proteins and carbohydrates, have received much attention due to their low toxicity, biodegradability, and biocompatibility. Among these, whey proteins-from whey, a byproduct of cheese manufacturing-have been considered as excellent delivery material because of their high nutritional value and various functional properties, such as binding capability to various compounds, gelation, emulsifying properties, and barrier effects. Since the functional and physicochemical properties of whey protein-based NDSs, including size and surface charge, can be key factors affecting the applications of NDSs in food, the objectives of this review are to discuss how manufacturing variables can modulate the functional and physicochemical properties of NDSs and bioavailability of encapsulated BCs to produce efficient NDSs for various BCs.

Lactadherin promotes microvesicle clearance to prevent coagulopathy and improves survival of severe TBI mice

Coagulopathy is common in patients with traumatic brain injury (TBI) and predicts poor clinical outcomes. We have shown that brain-derived extracellular microvesicles, including extracellular mitochondria, play a key role in the development of TBI-induced coagulopathy. Here, we further show in mouse models that the apoptotic cell-scavenging factor lactadherin, given at a single dose of 400 μg/kg 30 minutes before (preconditioning) or 30 minutes after cerebral fluid percussion injury, prevented coagulopathy as defined by clotting time, fibrinolysis, intravascular fibrin deposition, and microvascular bleeding of the lungs. Lactadherin also reduced cerebral edema, improved neurological function, and increased survival. It achieved these protective effects by enhancing the clearance of circulating microvesicles through phosphatidylserine-mediated phagocytosis. Together, these results identify the scavenging system for apoptotic cells as a potential therapeutic target to prevent TBI-induced coagulopathy and improve the outcome of TBI.

Cardiovascular benefits of combined interval training and post-exercise nutrition in type 2 diabetes

AIM

The purpose of this study was to examine whether the combination of high-intensity interval training (HIIT) and post-exercise protein supplementation would improve cardiovascular outcomes in individuals with T2D.

METHODS

In a double-blind controlled trial, fifty-three adults with T2D (free of CVD and not on exogenous insulin) were randomized to 12weeks of cardio and resistance-based HIIT (4-10×1min at 90% maximal heart rate) with post-exercise milk, milk-protein, or placebo supplementation, thrice weekly. Before and after, carotid and femoral artery intima media thickness (IMT) and femoral flow profiles were assessed using high-resolution ultrasound. Central and peripheral arterial stiffness were assessed by pulse wave velocity (PWV), and resting and maximal heart rate rates were measured.

RESULTS

After 12weeks of HIIT femoral IMT (Pre: 0.84±0.21mm vs. Post: 0.81±0.16mm, p=0.03), carotid-femoral PWV (Pre: 10.1±3.2m/s vs. Post: 8.6±1.8m/s, p<0.01) and resting heart rate (Pre: 70.4±10.8bpm vs. Post: 67.8±8.6 bpm, p=0.01) were all significantly lower. There were no differences between nutrition groups (all significant main effects of time) for all outcomes.

CONCLUSION

HIIT reduces femoral IMT, arterial stiffness and resting heart rate in individuals with T2D. The addition of post-exercise milk or protein to HIIT did not have additive effects for improving cardiovascular outcomes in the present study. Taken together, HIIT alone may be an effective means to reduce the burden of cardiovascular complications in T2D.

Protein-enriched, milk-based supplement to counteract sarcopenia in acutely ill geriatric patients offered resistance exercise training during and after hospitalisation: study protocol for a randomised, double-blind, multicentre trial

INTRODUCTION

Age-related loss of muscle mass and strength, sarcopaenia, burdens many older adults. The process is accelerated with bed rest, protein intakes below requirements and the catabolic effect of certain illnesses. Thus, acutely ill, hospitalised older adults are particularly vulnerable. Protein supplementation can preserve muscle mass and/or strength and, combining this with resistance exercise training (RT), may have additional benefits. Therefore, this study investigates the effect of protein supplementation as an addition to offering RT among older adults while admitted to the geriatric ward and after discharge. This has not previously been investigated.

METHODS AND ANALYSIS

In a block-randomised, double-blind, multicentre intervention study, 165 older adults above 70 years, fulfilling the eligibility criteria, will be included consecutively from three medical departments (blocks of n=20, stratified by recruitment site). After inclusion, participants will be randomly allocated (1:1) to receive either ready-to-drink, protein-enriched, milk-based supplements (a total of 27.5 g whey protein/day) or isoenergetic placebo products (<1.5 g protein/day), twice daily as a supplement to their habitual diet. Both groups will be offered a standardised RT programme for lower extremity muscle strength (daily while hospitalised and 4×/week after discharge). The study period starts during their hospital stay and continues 12 weeks after discharge. The primary endpoint is lower extremity muscle strength and function (30 s chair-stand-test). Secondary endpoints include muscle mass, measures of physical function and measures related to cost-effectiveness.

ETHICS AND DISSEMINATION

Approval is given by the Research Ethic Committee of the Capital Region of Denmark (reference no. H-16018240) and the Danish Data Protection Agency (reference no. HGH-2016-050). There are no expected risks associated with participation, and each participant is expected to benefit from the RT. Results will be published in peer-reviewed international journals and presented at national and international congresses and symposiums.

TRIAL REGISTRATION NUMBER

NCT02717819 (9 March 2016).

Effects of Milk Proteins Supplementation in Older Adults Undergoing Resistance Training: A Meta-Analysis of Randomized Control Trials

BACKGROUND

Older adults experience age-related physiological changes that affect body weight and body composition. In general, nutrition and exercise have been identified as potent stimulators of protein synthesis in skeletal muscle. Milk proteins are excellent sources of all the essential amino acids and may represent an ideal protein source to promote muscle anabolism in older adults undergoing resistance training. However, several randomized control trials (RCTs) have yielded mixed results on the effects of milk proteins supplementation in combination with resistance training on body weight and composition.

METHODS

PubMed, Web of Science and Cochrane databases were searched for literature that evaluated the effects of milk proteins supplementation on body weight and composition among older adults (age ≥ 60 years) undergoing resistance training up to September 2016. A random-effects model was used to calculate the pooled estimates and 95% confidence intervals (CIs) of effect sizes.

RESULTS

The final analysis included 10 RCTs involving 574 participants (mean age range from 60 to 80.8 years). Overall, the combination of milk proteins supplementation and resistance training did not have significant effect on fat mass (0.30, 95% CI -0.25, 0.86 kg) or body weight (1.02, 95% CI: -0.01, 2.04 kg). However, a positive effect of milk proteins supplementation paired with resistance training on fat-free mass was observed (0.74, 95% CI 0.30, 1.17 kg). Greater fat-free mass gains were observed in studies that included more than 55 participants (0.73, 95% CI 0.30, 1.16 kg), and in studies that enrolled participants with aging-related medical conditions (1.60, 95% CI 0.92, 2.28 kg). There was no statistical evidence of publication bias among the studies.

CONCLUSION

Our findings provide evidence that supplementation of milk protein, in combination with resistance training, is effective to elicit fat-free mass gain in older adults.

Fast digestive, leucine-rich, soluble milk proteins improve muscle protein anabolism, and mitochondrial function in undernourished old rats

SCOPE

One strategy to manage malnutrition in older patients is to increase protein and energy intake. Here, we evaluate the influence of protein quality during refeeding on improvement in muscle protein and energy metabolism.

METHODS AND RESULTS

Twenty-month-old male rats (n = 40) were fed 50% of their spontaneous intake for 12 weeks to induce malnutrition, then refed ad libitum with a standard diet enriched with casein or soluble milk proteins (22%) for 4 weeks. A 13C-valine was infused to measure muscle protein synthesis and expression of MuRF1, and MAFbx was measured to evaluate muscle proteolysis. mTOR pathway activation and mitochondrial function were assessed in muscle. Malnutrition was associated with a decrease in body weight, fat mass, and lean mass, particularly muscle mass. Malnutrition decreased muscle mTOR pathway activation and protein FSR associated with increased MuRF1 mRNA levels, and decreased mitochondrial function. The refeeding period partially restored fat mass and lean mass. Unlike the casein diet, the soluble milk protein diet improved muscle protein metabolism and mitochondrial function in old malnourished rats.

CONCLUSIONS

These results suggest that providing better-quality proteins during refeeding may improve efficacy of renutrition in malnourished older patients.

Oral immunotherapy for food allergy: A Spanish guideline. Immunotherapy egg and milk Spanish guide (items guide). Part I: Cow milk and egg oral immunotherapy: Introduction, methodology, rationale, current state, indications contraindications and oral immunotherapy build-up phase

INTRODUCTION

Cow's milk and egg are the most frequent causes of food allergy in the first years of life. Treatments such as oral immunotherapy (OIT) have been investigated as an alternative to avoidance diets. No clinical practice guides on the management of OIT with milk and egg are currently available.

OBJECTIVES

To develop a clinical guide on OIT based on the available scientific evidence and the opinions of experts.

METHODS

A review was made of studies published in the period between 1984 and June 2016, Doctoral Theses published in Spain, and summaries of communications at congresses (SEAIC, SEICAP, EAACI, AAAAI), with evaluation of the opinion consensus established by a group of experts pertaining to the scientific societies SEICAP and SEAIC.

RESULTS

Recommendations have been established regarding the indications, requirements and practical aspects of the different phases of OIT, as well as special protocols for patients at high risk of suffering adverse reactions.

CONCLUSIONS

A clinical practice guide is presented for the management of OIT with milk and egg, based on the opinion consensus of Spanish experts.

Emerging Evidence for the Importance of Dietary Protein Source on Glucoregulatory Markers and Type 2 Diabetes: Different Effects of Dairy, Meat, Fish, Egg, and Plant Protein Foods

Observational studies provide evidence that a higher intake of protein from plant-based foods and certain animal-based foods is associated with a lower risk for type 2 diabetes. However, there are few distinguishable differences between the glucoregulatory qualities of the proteins in plant-based foods, and it is likely their numerous non-protein components (e.g., fibers and phytochemicals) that drive the relationship with type 2 diabetes risk reduction. Conversely, the glucoregulatory qualities of the proteins in animal-based foods are extremely divergent, with a higher intake of certain animal-based protein foods showing negative effects, and others showing neutral or positive effects on type 2 diabetes risk. Among the various types of animal-based protein foods, a higher intake of dairy products (such as milk, yogurt, cheese and whey protein) consistently shows a beneficial relationship with glucose regulation and/or type 2 diabetes risk reduction. Intervention studies provide evidence that dairy proteins have more potent effects on insulin and incretin secretion compared to other commonly consumed animal proteins. In addition to their protein components, such as insulinogenic amino acids and bioactive peptides, dairy products also contain a food matrix rich in calcium, magnesium, potassium, trans-palmitoleic fatty acids, and low-glycemic index sugars-all of which have been shown to have beneficial effects on aspects of glucose control, insulin secretion, insulin sensitivity and/or type 2 diabetes risk. Furthermore, fermentation and fortification of dairy products with probiotics and vitamin D may improve a dairy product's glucoregulatory effects.

XP-828L in the Treatment of Mild to Moderate Psoriasis: Randomized, Double-Blind, Placebo-Controlled Study

Background:

XP-828L, a protein extract obtained from sweet whey, has demonstrated potential benefit for the treatment of mild to moderate psoriasis in an open-label study.

Objective:

To study in a randomized, double-blind, placebo-controlled study the safety and efficacy of XP-828L in the treatment of mild to moderate psoriasis.

Design:

XP-828L 5 g/d (group A, n = 42) or placebo (group B, n = 42) was given orally for 56 days followed by XP-828L 5 g/d in group A and by XP-828L 10 g/d in group B for an additional 56 days.

Results:

Patients receiving XP-828L 5 g/d for 56 days had an improved Physician's Global Assessment (PGA) score compared with patients under placebo ( p < .05). Considering the data of group A only, the PGA score improved from day 1 to day 56 ( p < .01); the Psoriasis Area and Severity Index score improved as well, but to a lesser extent ( p < .05).

Conclusion:

Oral administration of 5 g/d XP-828L compared with a placebo significantly improved the PGA score of patients with mild to moderate psoriasis.

Milk fat globule-EGF factor VIII attenuates CNS injury by promoting neural stem cell proliferation and migration after cerebral ischemia

The mediators in activating neural stem cells during the regenerative process of neurogenesis following stroke have not been fully identified. Milk fat globule-EGF Factor VIII (MFG-E8), a secreted glycoprotein serves several cellular functions by binding to its receptor, α_v β₃-integrin. However, its role in regulating neural stem cells after stroke has not been determined yet. We therefore, aim to reveal whether MFG-E8 promotes neural stem cell proliferation and migration during stroke. Stroke was induced in wild-type (Wt) and MFG-E8-deficinet (Mfge8^-/-) mice by transient middle cerebral artery occlusion (tMCAO). Commercially available recombinant mouse MFG-E8 (rmMFG-E8) was used for mechanistic assays in neural stem cell line, while the in house prepared recombinant human MFG-E8 (rhMFG-E8) was used for in vivo administration into rats with tMCAO. The in vitro effects of recombinant rmMFG-E8 for the neural stem cell proliferation and migration were determined by BrdU and transwell migration assay, respectively. The expression of cyclin D2, p53 and netrin-1, was analyzed by qPCR. We report that the treatment of rhMFG-E8 significantly improved the neurological deficit score, body weight lost and neural stem cell proliferation in a rat model of tMCAO. Conversely, decreased neural stem cell proliferation was observed in Mfge8^-/- mice in comparison with the Wt counterparts underwent tMCAO. rmMFG-E8 stimulated the proliferation of mouse embryonic neural stem cells via upregulation of cyclin D2 and downregulation of p53, which is mediated by α_v β₃-integrin. rmMFG-E8 also promoted mouse embryonic neural stem cell migration via α_v β₃-integrin dependent manner in upregulating netrin-1. Our findings suggest MFG-E8 to promote neural stem cell proliferation and migration, which therefore establishes a promising therapeutic strategy for cerebral ischemia.

[The nutrients of the milk on cardiovascular health]

The incidence of milk components on cardiovascular health is reviewed. A fraction of great interest in relation to cardiovascular disease is that of minerals, especially calcium. Benefits of milk in reducing blood pressure due to bioavailable calcium, along with other mineral elements present and bioactive peptides with antihypertensive ability, ACE inhibitors (key enzyme involved in the regulation of blood pressure) have been documented. Furthermore, a positive association of diets with high levels of calcium from milk, the fecal excretion of fat--which is favored by the same--and cardiovascular markers has also been reported. The presence in the milk of the essential, linoleic, linolenic and arachidonic fatty acids, although at low levels, is particularly interesting. Moreover, in the milk fat bioactive components as conjugated linoleic acid and sphingomyelin, which could exert potential cardioprotective effects are also present. However, because it contains high levels of saturated fatty acids, milk fat products consumption has been discouraged indiscriminately. According to the evidence collected in a long series of scientific studies it can be concluded that consumption of milk/dairy balanced and low-fat could be neutral effect or be inversely associated with cardiovascular risk.

Osteoporosis and Lifestyle

Skeletal tissue is formed during the first two decades of life; then a constant bone mass is maintained until 40 y of age. In the case of women, the bone mass is rapidly reduced at menopause at around 50 y of age. After that, bone mass slowly decreases in both men and women who have passed the 70-y-old mark. The National Institute of Health Consensus Conference adopted the definition of osteoporosis as a skeletal disorder that is characterized by compromised bone strength leading to a predisposition for and an increased risk of fracture. Since osteoporotic fractures are the third-highest cause for becoming bedridden, the maintenance of healthy bones is an important factor in extending a person's healthy lifespan. Bone mass is influenced by many factors, such as nutrition, physical activity, smoking and alcohol intake, as well as by genetic factors. Thus, a healthy diet providing balanced nutrients including calcium, vitamin D, vitamin K and protein, regular physical activity, and not smoking help maintain bone health and delay or prevent osteoporosis. Some functional foods containing soy isoflavones, milk basic protein and n-3 fatty acid may help promote bone health.

Dairy consumption and insulin sensitivity: a systematic review of short- and long-term intervention studies

AIM

Evidence from epidemiological studies suggests that higher consumption of dairy products may be inversely associated with risk of type 2 diabetes and other components of the metabolic syndrome, although the evidence is mixed. Intervention studies that increase dairy intake often involve lifestyle changes, including weight loss, which alone will improve insulin sensitivity. The aim of this review was to examine weight stable intervention studies that assess the effect of an increased intake of dairy products or dairy derived supplements on glucose metabolism and insulin sensitivity.

DATA SYNTHESIS

An electronic search was conducted using MEDLINE, EMBASE, the Cochrane Database and Web of Science for randomised controlled trials altering only dairy intake in humans with no other lifestyle or dietary change, particularly no weight change, and with measurement of glucose or insulin. Healthy participants and those with features of the metabolic syndrome were included. Chronic whey protein supplementation was also included. Ten studies were included in this systematic review.

CONCLUSIONS

In adults, four of the dairy interventions showed a positive effect on insulin sensitivity as assessed by Homeostasis Model Assessment (HOMA); one was negative and five had no effect. As the number of weight stable intervention studies is very limited and participant numbers small, these findings need to be confirmed by larger trials in order to conclusively determine any relationship between dairy intake and insulin sensitivity.

Whey protein plus bicarbonate supplement has little effects on structural atrophy and proteolysis marker immunopatterns in skeletal muscle disuse during 21 days of bed rest

OBJECTIVES

To investigate the effect of whey protein plus potassium bicarbonate supplement on disused skeletal muscle structure and proteolysis after bed rest (BR).

METHODS

Soleus (SOL) and vastus lateralis (VL) biopsies were sampled from ten (n=10) healthy male subjects (aged 31±6 years) who did BR once with and once without protein supplement as a dietary countermeasure (cross-over study design). The structural changes (myofibre size and type distribution) were analysed by histological sections, and muscle protein breakdown indirectly via the proteolysis markers, calpain 1 and 3, calpastatin, MuRF1 and 2, both in muscle homogenates and by immunohistochemistry.

RESULTS

BR caused size-changes in myofiber cross-sectional area (FCSA, SOL, p=0,004; VL, p=0.03), and myofiber slow-to-fast type transition with increased hybrids (SOL, p=0.043; VL, p=0.037) however with campaign differences in SOL (p<0.033). No significant effect of BR and supplement was found by any of the key proteolysis markers.

CONCLUSIONS

Campaign differences in structural muscle adaptation may be an issue in cross-over design BR studies. The whey protein plus potassium bicarbonate supplement did not attenuate atrophy and fibre type transition during medium term bed rest. Alkaline whey protein supplements may however be beneficial as adjuncts to exercise countermeasures in disuse.

Whey protein preloads are more beneficial than soy protein preloads in regulating appetite, calorie intake, anthropometry, and body composition of overweight and obese men

High-protein diets exert beneficial effects on appetite, anthropometry, and body composition; however, the effects of protein preloads depend on the amount, type, and time of consumption. Therefore, we hypothesized that long-term supplemental preloads of whey protein concentrate (WPC) and soy protein isolate (SPI) consumed 30 minutes before the largest meal would decrease appetite, calorie intake (CI), and anthropometry and improve body composition in overweight and obese men in free-living conditions. The subjects included 45 men with a body mass index between 25 and 40 kg/m(2) and who were randomly allocated to either the WPC (n = 26) or SPI (n = 19) groups. For 12 weeks, the subjects consumed 65 g WPC or 60 g SPI that was dissolved in 500 mL water 30 minutes before their ad libitum lunch. Appetite, CI, anthropometry, and body composition were assessed before and after the study and biweekly throughout. After 12 weeks, mean changes between the groups were significant for appetite (P = .032), CI (P = .045), anthropometry (body weight [P = .008], body mass index [P = .006], and waist circumference), and body composition (body fat mass and lean muscle [P < .001]). Relative to baseline, within-group mean changes from WPC were significant for appetite, CI, anthropometry, and body composition (P < .001). In the SPI group, mean changes were significant, relative to baseline, for all variables except lean muscle (P = .37). According to this 12-week study, WPC preloads conducted 30 minutes prior to the ad libitum main meal exerted stronger beneficial effects than did SPI preloads on appetite, CI, anthropometry, and body composition of free-living overweight and obese men.

Incretin, insulinotropic and glucose-lowering effects of whey protein pre-load in type 2 diabetes: a randomised clinical trial

AIMS/HYPOTHESIS

Since protein ingestion is known to stimulate the secretion of glucagon-like peptide-1 (GLP-1), we hypothesised that enhancing GLP-1 secretion to harness its insulinotropic/beta cell-stimulating activity with whey protein pre-load may have beneficial glucose-lowering effects in type 2 diabetes.

METHODS

In a randomised, open-label crossover clinical trial, we studied 15 individuals with well-controlled type 2 diabetes who were not taking any medications except for sulfonylurea or metformin. These participants consumed, on two separate days, 50 g whey in 250 ml water or placebo (250 ml water) followed by a standardised high-glycaemic-index breakfast in a hospital setting. Participants were randomised using a coin flip. The primary endpoints of the study were plasma concentrations of glucose, intact GLP-1 and insulin during the 30 min following meal ingestion.

RESULTS

In each group, 15 patients were analysed. The results showed that over the whole 180 min post-meal period, glucose levels were reduced by 28% after whey pre-load with a uniform reduction during both early and late phases. Insulin and C-peptide responses were both significantly higher (by 105% and 43%, respectively) with whey pre-load. Notably, the early insulin response was 96% higher after whey. Similarly, both total GLP-1 (tGLP-1) and intact GLP-1 (iGLP-1) levels were significantly higher (by 141% and 298%, respectively) with whey pre-load. Dipeptidyl peptidase 4 plasma activity did not display any significant difference after breakfast between the groups.

CONCLUSIONS/INTERPRETATION

In summary, consumption of whey protein shortly before a high-glycaemic-index breakfast increased the early prandial and late insulin secretion, augmented tGLP-1 and iGLP-1 responses and reduced postprandial glycaemia in type 2 diabetic patients. Whey protein may therefore represent a novel approach for enhancing glucose-lowering strategies in type 2 diabetes. Trial registration ClinicalTrials.gov NCT01571622 Funding The Israeli Ministry of Health and Milk Council funded the research.

Differential effects of proteins and carbohydrates on postprandial blood pressure-related responses

Diet composition may affect blood pressure (BP), but the mechanisms are unclear. The aim of the present study was to compare postprandial BP-related responses to the ingestion of pea protein, milk protein and egg-white protein. In addition, postprandial BP-related responses to the ingestion of maltodextrin were compared with those to the ingestion of sucrose and a protein mix. We hypothesised that lower postprandial total peripheral resistance (TPR) and BP levels would be accompanied by higher plasma concentrations of nitric oxide, insulin, glucagon-like peptide 1 (GLP-1) and glucagon. On separate occasions, six meals were tested in a randomised order in forty-eight overweight or obese adults with untreated elevated BP. Postprandial responses of TPR, BP and plasma concentrations of insulin, glucagon, GLP-1 and nitrite, nitroso compounds (RXNO) and S-nitrosothiols (NO(x)) were measured for 4 h. No differences were observed in TPR responses. Postprandial BP levels were higher after the ingestion of the egg-white-protein meal than after that of meals containing the other two proteins (P≤ 0·01). The ingestion of the pea-protein meal induced the highest NO(x) response (P≤ 0·006). Insulin and glucagon concentrations were lowest after the ingestion of the egg-white-protein meal (P≤ 0·009). Postprandial BP levels were lower after the ingestion of the maltodextrin meal than after that of the protein mix and sucrose meals (P≤ 0·004), while postprandial insulin concentrations were higher after the ingestion of the maltodextrin meal than after that of the sucrose and protein mix meals after 1-2 h (P≤ 0·0001). Postprandial NO(x), GLP-1 and glucagon concentrations were lower after the ingestion of the maltodextrin meal than after that of the protein mix meal (P≤ 0·008). In conclusion, different protein and carbohydrate sources induce different postprandial BP-related responses, which may be important for BP management. Lower postprandial BP levels are not necessarily accompanied by higher NO(x), insulin, glucagon or GLP-1 responses.

Efficacy of fermented milk and whey proteins in Helicobacter pylori eradication: A review

Helicobacter pylori (H. pylori) eradication is considered a necessary step in the management of peptic ulcer disease, chronic gastritis, gastric adenocarcinoma and mucosa associated lymphoid tissue lymphoma. Standard triple therapy eradication regimens are inconvenient and achieve unpredictable and often poor results. Eradication rates are decreasing over time with increase in antibiotic resistance. Fermented milk and several of its component whey proteins have emerged as candidates for complementary therapy. In this context the current review seeks to summarize the current evidence available on their role in H. pylori eradication. Pertinent narrative/systematic reviews, clinical trials and laboratory studies on individual components including fermented milk, yogurt, whey proteins, lactoferrin, α-lactalbumin (α-LA), glycomacropeptide and immunoglobulin were comprehensively searched and retrieved from Medline, Embase, Scopus, Cochrane Controlled Trials Register and abstracts/proceedings of conferences up to May 2013. A preponderance of the evidence available on fermented milk-based probiotic preparations and bovine lactoferrin suggests a beneficial effect in Helicobacter eradication. Evidence for α-LA and immunoglobulins is promising while that for glycomacropeptide is preliminary and requires substantiation. The magnitude of the potential benefit documented so far is small and the precise clinical settings are ill defined. This restricts the potential use of this group as a complementary therapy in a nutraceutical setting hinging on better patient acceptability/compliance. Further work is necessary to identify the optimal substrate, fermentation process, dose and the ideal clinical setting (prevention/treatment, first line therapy/recurrence, symptomatic/asymptomatic, gastritis/ulcer diseases etc.). The potential of this group in high antibiotic resistance or treatment failure settings presents interesting possibilities and deserves further exploration.

A novel protein mixture containing vegetable proteins renders enteral nutrition products non-coagulating after in vitro gastric digestion

BACKGROUND & AIMS

Non-coagulation of protein from enteral nutrition (EN) in the stomach is considered to improve gastric emptying and may result in reduced upper gastrointestinal complications such as reflux and aspiration pneumonia. For the development of a new EN protein mixture with reduced gastric coagulation, the coagulating properties of individual proteins, a novel blend of four proteins (P4 protein blend) and commercial EN products were investigated.

METHODS

A semi-dynamic, computer controlled setup was developed to mimic gastric digestion. The coagulation behaviour of 150 ml protein solutions and EN products was investigated. These were heat-treated calcium caseinate, sodium caseinate, whey, soy and pea protein, and the P4 protein blend comprising of the latter four (all solutions 6% w/v protein), four new enteral nutrition product varieties (New Nutrison® .0 or 1.5 kcal/ml, with and without MultiFibre MF6™) based on the P4 protein blend and two other commercially available casein dominant EN products (T1 and T2).

RESULTS

Calcium caseinate and sodium caseinate yielded a total wet coagulate of 43.5 ± 0.7 g and 52.7 ± 6.2 g, respectively. Whey, soy, pea and the P4 protein blend did not produce any measurable coagulate. T1 and T2 resulted in a total wet coagulate of 37.5 ± 0.8 g and 57.3 ± 0.8 g, respectively, while all new EN product varieties based on the P4 protein blend did not produce any measurable coagulate.

CONCLUSIONS

The P4 protein blend renders EN product varieties non-coagulating after in vitro gastric digestion.

Milk oral immunotherapy is effective in school-aged children

AIMS

  To study the efficacy of oral immunotherapy (OIT) in schoolchildren with cow's milk (CM) allergy (CMA).

METHODS

  Twenty-eight children aged 6-14 years with CMA documented by oral challenge were enrolled into a randomized, double-blind, placebo-controlled OIT study. In the active treatment, CM protein amount was increased during 23 weeks from 0.06 mg to a maximum of 6400 mg (200 mL of milk).

RESULTS

  Twenty-four (86%) patients completed the protocol: 16/18 in active and 8/10 in placebo groups. All children in the active and 2/3 in the placebo group suffered from symptoms considered by the parents as induced by milk. The children were contacted by phone 12 months later, and 13 (81%) used daily CM or milk products corresponding 6400 mg of CM protein. After double-blind OIT, all 10 children in the placebo group completed successfully an open-label OIT by an identical protocol, and all used daily CM or milk products 6 months later. Three to 3.5 years later, one child more had discontinued daily milk use. Thus, the long-term success rate was 22/28 (79%).

CONCLUSIONS

  This placebo-controlled, double-blind study confirmed that OIT was effective in desensitizing schoolchildren with CMA. With occasional exceptions, the reached desensitization sustained for more than 3 years.

Treatment of moderate acute malnutrition with ready-to-use supplementary food results in higher overall recovery rates compared with a corn-soya blend in children in southern Ethiopia: an operations research trial

BACKGROUND

Moderate and severe acute malnutrition affects 13% of children <5 y of age worldwide. Severe acute malnutrition affects fewer children but is associated with higher rates of mortality and morbidity. Supplementary feeding programs aim to treat moderate acute malnutrition and prevent the deterioration to severe acute malnutrition.

OBJECTIVE

The aim was to compare recovery rates of children with moderate acute malnutrition in supplementary feeding programs by using the newly recommended ration of ready-to-use supplementary food (RUSF) and the more conventional ration of corn-soya blend (CSB) in Ethiopia.

DESIGN

A total of 1125 children aged 6-60 mo with moderate acute malnutrition received 16 wk of CSB or RUSF. Children were randomly assigned to receive one or the other food. The daily rations were purposely based on the conventional treatment rations distributed at the time of the study in Ethiopia: 300 g CSB and 32 g vegetable oil in the control group (1413 kcal) and 92 g RUSF in the intervention group (500 kcal). The higher ration size of CSB was provided because of expected food sharing.

RESULTS

The HR for children in the CSB group was 0.85 (95% CI: 0.73, 0.99), which indicated that they had 15% lower recovery (P = 0.039). Recovery rates of children at the end of the 16-wk treatment period trended higher in the RUSF group (73%) than in the CSB group (67%) (P = 0.056).

CONCLUSION

In comparison with CSB, the treatment of moderate acute malnutrition with RUSF resulted in higher recovery rates in children, despite the large ration size and higher energy content of the conventional CSB ration.

Nourishing the dysfunctional gut and whey protein

PURPOSE OF REVIEW

This review discusses the mechanisms of the dysfunctional gut during the critical illness and the possibility that an immunonutrient such as whey protein can play a role in better tolerance of enteral nutrition, also decreasing inflammation and increasing anti-inflammatory defenses.

RECENT FINDINGS

Impaired gastric motor function and associated feed intolerance are common issues in critically ill patients. Some studies have been published with enteral nutrition enriched with whey protein as a dietary protein supplement that provides antimicrobial activity, immune modulation, improving muscle strength and body composition, and preventing cardiovascular disease and osteoporosis.

SUMMARY

Early enteral feeding will enhance patient recovery and the use of enteral diets enriched with whey protein may play a role in these patients.

Fermented milk for hypertension

BACKGROUND

Fermented milk has been suggested to have a blood pressure lowering effect through increased content of proteins and peptides produced during the bacterial fermentation. Hypertension is one of the major risk factors for cardiovascular disease world wide and new blood pressure reducing lifestyle interventions, such as fermented milk, would be of great importance.

OBJECTIVES

To investigate whether fermented milk or similar products produced by lactobacilli fermentation of milk proteins has any blood pressure lowering effect in humans when compared to no treatment or placebo.

SEARCH METHODS

The Cochrane Central Register of Controlled Trials (CENTRAL), English language databases, including MEDLINE (1966-2011), EMBASE (1974-2011), Cochrane Complementary Medicine Trials Register, Allied and Complementary Medicine (AMED) (1985-2011), Food science and technology abstracts (1969-2011).

SELECTION CRITERIA

Randomised controlled trials; cross over and parallel studies evaluating the effect on blood pressure of fermented milk in humans with an intervention period of 4 weeks or longer.

DATA COLLECTION AND ANALYSIS

Data was extracted individually by two authors, afterwards agreement had to be obtained before imputation in the review.

MAIN RESULTS

A modest overall effect of fermented milk on SBP was found (MD -2.45; 95% CI -4.30 to -0.60), no effect was evident on DBP (MD -0.67; 95% CI -1.48, 0.14).

AUTHORS' CONCLUSIONS

The review does not support an effect of fermented milk on blood pressure. Despite the positive effect on SBP the authors conclude, for several reasons, that fermented milk has no effect on blood pressure. The effect found was very modest and only on SBP, the included studies were very heterogeneous and several with weak methodology. Finally, sensitivity and subgroup analyses could not reproduce the antihypertensive effect. The results do not give notion to the use of fermented milk as treatment for hypertension or as a lifestyle intervention for pre-hypertension nor would it influence population blood pressure.

Delay of stroke onset by milk proteins in stroke-prone spontaneously hypertensive rats

BACKGROUND AND PURPOSE

There is an inverse association between dairy food consumption and the incidence of stroke in observational studies. However, it is unknown whether the relationship is causal or, if so, what components in milk are responsible for reducing the incidence of stroke.

METHODS

Stroke-prone spontaneously hypertensive rats were fed diets comprising amino acids, proteins from different sources (casein, whey, soybean, or egg white), or fats from different sources (butter, beef tallow, or cocoa butter) and the onset of stroke and lifespan were examined.

RESULTS

Increasing the amount of dietary casein (5% to 55% of caloric intake) markedly delayed the onset of stroke. However, when stroke-prone spontaneously hypertensive rats were fed diets containing 55% of caloric intake as protein, rats fed casein or whey protein, a major component of milk, displayed a delayed onset of stroke compared with rats fed soybean or egg white protein. Rats fed an amino acids diet containing the same amino acids composition as casein did not have a delay in the onset of stroke. Increasing dietary fats, including butter as well as beef tallow and cocoa butter, did not affect the onset of stroke. All diets did not affect blood pressure in the early stage.

CONCLUSIONS

These data suggest that the inverse association between dairy food consumption and incidence of stroke in epidemiological studies is causal and that peptides in milk protein, but not fat, might be responsible for this effect.

A novel fortified blended flour, corn-soy blend "plus-plus," is not inferior to lipid-based ready-to-use supplementary foods for the treatment of moderate acute malnutrition in Malawian children

BACKGROUND

Children with moderate acute malnutrition (MAM) are often treated with fortified blended flours, most commonly a corn-soy blend (CSB). However, recovery rates remain <75%, lower than the rate achieved with peanut paste-based ready-to-use supplementary foods (RUSFs). To bridge this gap, a novel CSB recipe fortified with oil and dry skim milk, "CSB++," has been developed.

OBJECTIVE

In this trial we compared CSB++ with 2 RUSF products for the treatment of MAM to test the hypothesis that the recovery rate achieved with CSB++ will not be >5% worse than that achieved with either RUSF.

DESIGN

We conducted a prospective, randomized, investigator-blinded, controlled noninferiority trial involving rural Malawian children aged 6-59 mo with MAM. Children received 75 kcal CSB++ · kg(-1) · d(-1), locally produced soy RUSF, or an imported soy/whey RUSF for ≤12 wk.

RESULTS

The recovery rate for CSB++ (n = 763 of 888; 85.9%) was similar to that for soy RUSF (795 of 806, 87.7%; risk difference: -1.82%; 95% CI: -4.95%, 1.30%) and soy/whey RUSF (807 of 918, 87.9%; risk difference: -1.99%; 95% CI: -5.10%, 1.13%). On average, children who received CSB++ required 2 d longer to recover, and the rate of weight gain was less than that with either RUSF, although height gain was the same among all 3 foods studied.

CONCLUSIONS

A novel, locally produced, fortified blended flour (CSB++) was not inferior to a locally produced soy RUSF and an imported soy/whey RUSF in facilitating recovery from MAM. The recovery rate observed for CSB++ was higher than that for any other fortified blended flour tested previously. This trial is registered at clinicaltrials.gov as NCT00998517.

Expression and characterization of recombinant human milk fat globule-EGF factor VIII

Apoptosis plays an important role in the patho-biology of sepsis. The opsonizing protein milk fat globule-EGF factor VIII (MFG-E8) is involved in apoptotic cell clearance. Our previous studies have shown that administration of rat MFG-E8-containing exosomes or recombinant murine MFG-E8 (rmMFG-E8) is protective in a rat model of sepsis induced by cecal ligation of puncture (CLP). However, one obstacle hampering the development of MFG-E8 as a therapeutic agent for septic patients is the potential immunogenicity of animal proteins in humans. The purpose of this study, therefore, was to express recombinant human MFG-E8 (rhMFG-E8) and characterize its biological activity. Using an E. coli system, we successfully expressed and purified the mature molecule of human MFG-E8 (Leu24-Cys387). The purity of rhMFG-E8 was over 99% and it was immunoreactive for specific anti-human MFG-E8 antibodies. Amino acid sequence analysis by LC-MS/MS identified the purified protein as human MFG-E8. Using primary rat peritoneal macrophages, we showed that rhMFG-E8 markedly increased peritoneal macrophage phagocytosis of apoptotic thymocytes, which was as effective as commercial rmMFG-E8. To determine the biological activity of rhMFG-E8 in vivo, male adult rats were subjected to sepsis by CLP. rhMFG-E8 or rmMFG-E8 were administered intravenously at the time of CLP. Our results demonstrated that both rhMFG-E8 and rmMFG-E8 reduced thymocyte apoptosis and plasma levels of lactate and IL-6 at 20 h after CLP, and improved the 10-day survival rate. Thus, we have successfully expressed and purified biologically active rhMFG-E8. Our newly-expressed rhMFG-E8 is highly effective in the rat model of sepsis.

[Hydrolysis method for whey protein and the hypoglycemic activity of its peptides in diabetic KKAy mice]

OBJECTIVE

To explore the hydrolysis method for whey protein with alkaline proteinase, and to investigate the hypoglycemic activity of the peptides in diabetic KKAy mice.

METHODS

Whey protein was hydrolyzed with alkaline proteinase, and the degree of hydrolysis, nitrogen and amino acid content, mass spectrographic analysis of the peptides were determined. Changes of fasting blood glucose, random blood glucose, glucose tolerance and insulin levels in diabetic KKAy mice were measured after the peptides were given by gavage.

RESULTS

The degree of hydrolysis of whey protein was 14.8%, the nitrogen in the peptides was 68.2%, and the molecular weight of the peptides was 900 - 1900 Dal, mostly was 1800 - 1900 Dal. Blood glucose of KKAy mice was decreased at 0.5 and 1 h after oral injection of the peptides, and insulin level was increased at 0.5 h after ingestion of the peptides.

CONCLUSION

Fasting blood glucose and random blood glucose levels of type 2 diabetic KKAy mice could be significantly decreased, and the glucose tolerance and insulin secretion of mice could be improved by whey protein peptides.

Similar effects of leucine rich and regular dairy products on muscle mass and functions of older polymyalgia rheumatica patients: a randomized crossover trial

OBJECTIVES

Leucine-rich milk and whey proteins have been suggested for prevention of age related loss of muscle mass and strength i.e. sarcopenia. The effects of milk protein supplementation and low intensity home based physical exercise on body composition and muscle functions were investigated.

DESIGN

A randomized double blind crossover trial.

SETTING

Community dwelling members of Helsinki rheumatoid association.

PARTICIPANTS

Older people (N=47, mean age 69.5 years) suffering from polymyalgia rheumatica.

INTERVENTION

Patients performed as many stand ups as possible twice a day after which they ingested a regular (Control) or a whey protein enriched dairy product with high leucine content (Test). The 8-week intervention periods were separated by a 4-week wash-out.

MEASUREMENTS

Body composition was measured by dual x-ray absorptiometry and muscle functions by hand grip strength, force platform countermovement jump performance, chair stand test, and walking speed.

RESULTS

The 16-week home-based post-exercise supplementation resulted in a 1.8% increase (p = 0.052) in lower limb muscle mass. Walking speed (+5.3%, p = 0.007) and chair stand test performance (-12.2 %, p < 0.001) were also improved. Furthermore, a tendency for increased jump power (+3.0%, p = 0.084) was observed. However, significant and consistent differences were not found in the changes of muscle mass indices or muscle functions between supplements, but the test supplement tended to prevent accumulation of body fat.

CONCLUSION

A low intensity home based exercise program combined with post-exercise milk protein supplementation is feasible despite some gastrointestinal complaints and seems effective in improving the muscle mass and functions of older persons with a inflammatory disease. Further studies are needed to establish, whether and to what extent the use of leucine-enriched whey products prevent or treat age-associated sarcopenia and whether they are superior to the present commercial milk products.

The effects of dietary and nutrient interventions on arterial stiffness: a systematic review

BACKGROUND

Although dietary and nutrient interventions have been extensively studied as a means of improving arterial stiffness, to our knowledge no systematic analysis of the data has been conducted.

OBJECTIVE

The aim of the current study was to systematically review the human clinical trial data and qualitatively examine the efficacy of dietary and nutrient interventions in the treatment of arterial stiffness.

DESIGN

We systematically searched multiple databases until July 2010 for relevant randomized controlled human clinical trials of common dietary and nutrient interventions in the treatment of arterial stiffness. Located studies were subject to strict inclusion criteria and objectively assessed for scientific quality.

RESULTS

Of the 75 relevant studies located, we considered 38 studies to be appropriate for review. Results revealed support for intakes of omega-3 (n-3) fish oils (Cohen's d = 0.21-0.81) and soy isoflavones (Cohen's d = 0.35-0.39) in the treatment of arterial stiffness. There was limited but consistent evidence to suggest that salt restriction (Cohen's d = 0.28-0.37) as well as consumption of fermented-milk products (Cohen's d = 0.15-0.33) that contain bioactive peptides improved arterial stiffness. The evidentiary support for intakes of vitamins, micronutrients, and herbal medicines was insufficient. Limited but consistent evidence suggested that caffeine intake acutely increased arterial stiffness (Cohen's d = 0.34-0.51).

CONCLUSIONS

Current evidence from several small studies suggests that omega-3 and soy isoflavone supplementation provides an effective means of reducing arterial stiffness. There was little research that explored intakes of herbal medicines or micronutrients in the treatment of arterial stiffness, and this remains an area of potential research.

The chronic effects of whey proteins on blood pressure, vascular function, and inflammatory markers in overweight individuals

Limited evidence suggests that dairy whey protein may be the major dairy component that is responsible for health benefits currently associated with increased dairy consumption. Whey proteins may reduce blood pressure and improve cardiovascular health. This study evaluated the effects of whey protein supplementation on blood pressure, vascular function and inflammatory markers compared to casein and glucose (control) supplementation in overweight/obese individuals. The subjects were randomized to either whey protein, casein or glucose supplementation for 12 weeks according to a parallel design. In all, 70 men and women with a mean (+/-s.e.m.) BMI (kg/m(2)) of 31.3 +/- 0.8 completed the study. Systolic blood pressure (SBP) decreased significantly at week 6 compared to baseline in the whey and casein groups, (P = 0.028 and P = 0.020, respectively) and at week 12 (P = 0.020, and P = 0.017, respectively). Diastolic blood pressure (DBP) decreased significantly compared to baseline in the whey and casein groups (P = 0.038 and P = 0.042, respectively) at week 12. DBP decreased significantly in the whey and casein groups (P = 0.025, P = 0.038, respectively) at week 12 compared to the control group. Augmentation index (AI) was significantly lower from baseline at 12 weeks (P = 0.021) in the whey group. AI decreased significantly in the whey group at 12 weeks compared to control (P = 0.006) and casein (P = 0.006). There were no significant changes in inflammatory markers within or between groups. This study demonstrated that supplementation with whey protein improves blood pressure and vascular function in overweight and obese individuals.

Dairy protein attenuates weight gain in obese rats better than whey or casein alone

Evidence suggests that dietary calcium (Ca) and particularly dairy foods may attenuate weight gain and improve symptoms of the metabolic syndrome. The purpose of this study was to determine the effect of different Ca-enriched dairy protein sources on the prevention of weight gain in Sprague-Dawley diet-induced obese (DIO) rats. Twelve week-old DIO rats were assigned to one of eight ad libitum diets that varied in protein source (casein, whey, or complete dairy), Ca content (0.67 or 2.4%) and energy level (high fat/high sucrose (HFHS); or normal calorie density (NC)). Body composition and response to a meal tolerance test (MTT) were measured. Average daily caloric intake did not differ within normal or high energy density groups. At the end of 8 weeks, the dairy/HFHS/0.67% and 2.4% groups had significantly lower body weight than all other HFHS groups. The dairy/HFHS/0.67% and 2.4% groups also had lower body fat and greater lean mass expressed as a percent (P < 0.05). Homeostatic model assessment of insulin resistance (HOMA(IR)) was lowest for dairy/HFHS/0.67% and significantly different from whey/HFHS/0.67% and 2.4%. Independent of protein source, high Ca decreased plasma insulin at 30 min in the MTT more so than low Ca (P < 0.05). Hepatic sterol regulatory element-binding protein (SREBP1c) and peroxisome proliferator-activated receptor-gamma (PPARgamma) mRNA was downregulated by dairy and whey compared to casein in the HFHS/0.67% diets. Overall, these data suggest that complete dairy improves body composition and insulin sensitivity to a greater extent than whey or casein alone.

Effect of a whey-predominant starter formula containing LCPUFAs and oligosaccharides (FOS/GOS) on gastrointestinal comfort in infants

Development of new infant formulas aims to replicate the benefits of breast milk. One benefit of breast milk over infant formulas is greater gastrointestinal comfort. We compared indicators of gastrointestinal comfort in infants fed a whey-predominant formula containing long-chain polyunsaturated fatty acids, galacto-oligo-saccharides and fructo-oligosaccharides, and infants fed a control casein-predominant formula without additional ingredients. The single-centre, prospective, double-blind, controlled trial randomly assigned healthy, full-term infants (n=144) to receive exclusively either experimental or control formula from 30 days to 4 months of age. A group of exclusively breast-fed infants served as reference (n=80). At 1, 2, 3, and 4 months, infants' growth parameters were measured and their health assessed. Parents recorded frequency and physical characteristics of infants' stool, frequency of regurgitation, vomiting, crying and colic. At 2-months, gastric emptying (ultrasound) and intestinal transit time (H2 breath test) were measured, and stool samples collected for bacterial analysis. Compared to the control (n=69), fewer of the experimental group (n=67) had hard stools (0.7 vs 7.5%, p<0.001) and more had soft stools (90.8 vs 82.3%, p<0.05). Also compared to the control, the experimental group's stool microbiota composition (mean % bifidobacteria: 78.1 (experimental, n=17), 63.7 (control, n=16), 74.3 (breast-fed, n=20), gastric transit times (59.6 (experimental, n=53), 61.4 (control, n=62), 55.9 (breast-fed, n=67) minutes) and intestinal transit times (data not shown) were closer to that of the breast-fed group. Growth parameter values were similar for all groups. The data suggest that, in infants, the prebiotic-containing whey-based formula provides superior gastrointestinal comfort than a control formula.

Zinc increases the effects of essential amino acids-whey protein supplements in frail elderly

Protein undernutrition is frequent in the elderly. It contributes to the development of osteoporosis, possibly via lower IGF-I. Dietary zinc can influence IGF-I production.

OBJECTIVES

To determine the influence of dietary zinc addition on IGF-I and bone turnover responses to essential amino acids-whey (EAA-W) protein supplements in frail elderly.

DESIGN AND SETTING

A daily oral protein supplement was given to hospitalized patients for 4 weeks. On a randomized, double-blind basis, patients received either an additional 30 mg/day of zinc or control.

PARTICIPANTS

Sixty-one hospitalized elderly aged 66.7 to 105.8, with a mini-nutritional assessment score between 17 and 24 were enrolled.

MEASUREMENTS

Activities of daily living; dietary intakes; serum IGF-I, IGF-BP3, CrossLapsTM, osteocalcin and zinc were measured before and after 1, 2 and 4 weeks of protein supplementation.

RESULTS

Serum IGF-I rapidly increased in both groups. Zinc accelerated this increase with changes of +48.2 +/- 14.3 and +22.4 +/- 4.7% (p < .05) by 1 week, in the zinc-supplemented and control groups, respectively. Zinc significantly decreased the serum bone resorption marker CrossLapsTM by already 1 week. Activities of daily living improved by +27.0 +/- 3.1 and +18.3 +/- 4.5% in zinc-supplemented and control groups, respectively.

CONCLUSION

In the elderly, zinc supplementation accelerated the serum IGF-I response to EAA-W protein by 1 week and decreased a biochemical marker of bone resorption.

Nutritional management of PKU with glycomacropeptide from cheese whey

Individuals with phenylketonuria (PKU) must follow a lifelong low-phenylalanine (Phe) diet to prevent neurological impairment. Compliance with the low-Phe diet is often poor owing to restriction in natural foods and the requirement for consumption of a Phe-free amino acid formula or medical food. Glycomacropeptide (GMP), a natural protein produced during cheese-making, is uniquely suited to a low-Phe diet because when isolated from cheese whey it contains minimal Phe (2.5-5 mg Phe/g protein). This paper reviews progress in evaluating the safety, acceptability and efficacy of GMP in the nutritional management of PKU. A variety of foods and beverages can be made with GMP to improve the taste, variety and convenience of the PKU diet. Sensory studies in individuals with PKU demonstrate that GMP foods are acceptable alternatives to amino acid medical foods. Studies in the PKU mouse model demonstrate that GMP supplemented with limiting indispensable amino acids provides a nutritionally adequate source of protein and improves the metabolic phenotype by reducing concentrations of Phe in plasma and brain. A case report in an adult with classical PKU who followed the GMP diet for 10 weeks at home indicates safety, acceptability of GMP food products, a 13-14% reduction in blood Phe levels (p<0.05) and improved distribution of dietary protein throughout the day compared with the amino acid diet. In summary, food products made with GMP that is supplemented with limiting indispensable amino acids provide a palatable alternative source of protein that may improve dietary compliance and metabolic control of PKU.

[Recurrence of Clostridium difficile-associated diarrhoea prevented by the administration of a whey concentrate from specifically immunised cows; prospective study]

OBJECTIVE

To try to prevent recurrences of Clostridium difficile-associated diarrhoea (CDAD) by treatment with a specific neutralising secretory IgA-enriched whey-protein concentrate (40%) made from the milk of cows immunised with C. difficile and its toxins.

DESIGN

Prospective, non-blinded, clinical cohort study.

METHOD

In 2005-2006, 100 consecutive patients with CDAD received the whey concentrate for 2 weeks after completion of standard antibiotic therapy. For a period of 60 days after the start of the administration, the safety and preliminary efficacy of the whey concentrate were evaluated by means of a diary, blood determinations, active surveillance for adverse events, and the recurrence of CDAD.

RESULTS

The whey concentrate was well tolerated and no safety issues were raised. Eleven out of 109 episodes (10%) were followed by a recurrence. After completion of the whey concentrate therapy, a positive test for faecal toxins or culture of C. difficile was predictive for the recurrence of CDAD (relative risk: 8.2 (95% CI: 1.04-64), and 4.7 (95% CI: 0.5-47), respectively). A positive faeces toxin during administration of the whey concentrate was also associated with an early recurrence of CDAD.

CONCLUSION

Compared to historical and contemporary findings in control groups, the whey concentrate appeared to reduce the recurrence of CDAD by about 50%. However, the standard dose of the whey concentrate was probably not sufficient to fully neutralise the C. difficile toxins in faeces in all episodes.

XP-828L in the treatment of mild to moderate psoriasis: randomized, double-blind, placebo-controlled study

BACKGROUND

XP-828L, a protein extract obtained from sweet whey, has demonstrated potential benefit for the treatment of mild to moderate psoriasis in an open-label study.

OBJECTIVE

To study in a randomized, double-blind, placebo-controlled study the safety and efficacy of XP-828L in the treatment of mild to moderate psoriasis.

DESIGN

XP-828L 5 g/d (group A, n=42) or placebo (group B, n=42) was given orally for 56 days followed by XP-828L 5 g/d in group A and by XP-828L 10 g/d in group B for an additional 56 days.

RESULTS

Patients receiving XP-828L 5 g/d for 56 days had an improved Physician's Global Assessment (PGA) score compared with patients under placebo (p less than 0.05). Considering the data of group A only, the PGA score improved from day 1 to day 56 (p less than 0.01); the Psoriasis Area and Severity Index score improved as well, but to a lesser extent (p less than 0.05).

CONCLUSION

Oral administration of 5 g/d XP-828L compared with a placebo significantly improved the PGA score of patients with mild to moderate psoriasis.

Milk basic protein increases alveolar bone formation in rat experimental periodontitis

BACKGROUND AND OBJECTIVE

It is conceivable that the active components extracted from milk whey protein (i.e. milk basic protein, MBP) stimulate bone formation and suppress bone resorption. Periodontitis is characterized by excessive alveolar bone resorption. We examined whether milk basic protein could recover alveolar bone loss in rat experimental periodontitis.

MATERIAL AND METHODS

A nylon ligature was placed around the cervix of molars in 8-wk-old male Fischer rats for 20 d. Then, the ligature was removed and a powder diet containing 0.2 or 1.0% milk basic protein was provided daily for another 45-90 d. On days 45 and 90, the maxillae were extracted and analyzed using microcomputerized tomography (micro-CT), followed by histological analysis.

RESULTS

Micro-CT images showed that alveolar bone resorption was severely induced around the molar by the 20-d ligature procedure. Treatment with high-dose milk basic protein (1.0%) clearly recovered ligature-induced alveolar bone resorption on days 45 and 90, whereas low-dose milk basic protein (0.2%) did not show such a clear effect. Histological examination clarified that the osteoid thickness of alveolar bone was dose dependently increased by milk basic protein treatment for 90 d.

CONCLUSION

These findings suggest that a systemic administration of milk basic protein may be effective for the recovery of alveolar bone loss in periodontitis.

Blutdrucksenkende Tripeptide aus der Milch

Milchfermentierung mit dem Lactobacillus helveticus LBK-16H führt zur Freisetzung der Kaseintripeptide Val-Pro-Pro und Ile-Pro-Pro. Diese Peptide hemmen die Kininase II (auch Angiotensin Converting Enzyme, ACE genannt). Wenn genügend grosse Mengen dieser Peptide in Milchgetränken über mehrere Wochen täglich eingenommen werden, sinkt der Blutdruck bei Hypertonikern geringgradig ab. Die bisher erhältlichen Milchpeptide senken den Blutdruck weniger stark als die antihypertensiven Medikamente und sind deshalb nur als begleitende und gut verträgliche Lebensstilanpassungen zur Vorbeugung und Behandlung des Bluthochdrucks einsetzbar.

A Role for Milk Proteins and their Peptides in Cancer Prevention

A role for the amount and type of dietary protein in the etiology of cancer has not been studied extensively. Nevertheless, there is no compelling evidence from epidemiological studies to indicate that protein, at levels usually consumed, is a risk factor for cancer. On the other hand, animal studies suggest that certain peptides and amino acids derived from dietary proteins may influence carcinogenesis. The predominant protein in milk, casein, its peptides, but not liberated amino acids, have antimutagenic properties. Animal models, usually for colon and mammary tumorigenesis, nearly always show that whey protein is superior to other dietary proteins for suppression of tumour development. This benefit is attributed to its high content of cystine/cysteine and gamma-glutamylcyst(e)ine dipeptides, which are efficient substrates for the synthesis of glutathione. Glutathione is an ubiquitous cellular antioxidant that directly or through its associated enzymes destroys reactive oxygen species, detoxifies carcinogens, maintains proteins in a reduced state and ensures a competent immune system. Various experiments showed that tumour prevention by dietary whey protein was accompanied by increased glutathione levels in serum and tissues as well as enhanced splenic lymphocyte proliferation, phagocytosis and natural killer, T helper and cytotoxic T cell activity. Whey protein components, beta-lactoglobulin, alpha-lactalbumin and serum albumin were studied infrequently, but results suggest they have anticancer potential. The minor component lactoferrin has received the most attention; it inhibits intestinal tumours and perhaps tumours at other sites. Lactoferrin acts by induction of apoptosis, inhibition of angiogenesis, modulation of carcinogen metabolising enzymes and perhaps acting as an iron scavenger. Supplementing cows with selenium increases the content of selenoproteins in milk, which on isolation inhibited colon tumorigenesis in rats.

Milk peptides and blood pressure

Epidemiological studies suggest that milk consumption and dietary intake of dairy proteins are inversely related to the risk for hypertension. Also, some intervention studies have shown a blood pressure-lowering effect of milk products and dairy proteins. Milk peptides are formed from milk proteins by enzymatic breakdown by digestive enzymes or by the proteinases formed by lactobacilli during the fermentation of milk. Several milk peptides have been shown to have antihypertensive effects in animal and in clinical studies. The most studied mechanism underlying the antihypertensive effects of milk peptides is inhibition of angiotensin-converting enzyme. Milk peptides may also have other additional mechanisms to lower blood pressure such as opioid-like activities and mineral-binding and antithrombotic properties. The future challenge is to identify the antihypertensive components in milk and their mechanisms of action and thus to find more possibilities for using these constituents and products as a dietary treatment of hypertension.