Effect of an egg ovalbumin-derived protein hydrolysate on blood pressure and cardiovascular risk in adults with a mildly elevated blood pressure: a randomized placebo-controlled crossover trial

Ovalbumin Hydrolysates Enhance Skeletal Muscle Insulin-Dependent Signaling Pathway in High-Fat Diet-Fed Mice

Egg white hydrolysates (EWH) and ovotransferrin-derived peptides have distinct beneficial effects on glucose metabolism. This research aims to investigate whether ovalbumin hydrolysates (OVAHs), without ovotransferrin can improve insulin signaling pathway in high-fat diet (HFD)-fed mice. Two types of ovalbumin hydrolysates were produced, either using thermoase (OVAT), or thermoase + pepsin (OVATP). Both OVAHs-supplemented groups exhibited lower body weight gain (P < 0.001) and enhanced oral glucose tolerance (P < 0.05) compared with HFD. Moreover, diet supplementation with either hydrolysate increased the insulin-stimulated activation of protein kinase B (AKT) and insulin receptor β (IRβ) (P < 0.0001) in skeletal muscle. In conclusion, OVAHs improved glucose tolerance and insulin-dependent signaling pathway in HFD-fed mice.

Longer-term effects of the egg-protein hydrolysate NWT-03 on arterial stiffness and cardiometabolic risk markers in adults with metabolic syndrome: a randomized, double-blind, placebo-controlled, crossover trial

BACKGROUND

Short-term intake of egg-derived protein hydrolysates, such as NWT-03, suggest improvements in arterial stiffness and metabolic profiles, but longer-term trials are lacking. This study therefore examined the longer-term effects of NWT-03 on arterial stiffness and cardiometabolic markers in men and women with metabolic syndrome.

METHODS

Seventy-six adults with metabolic syndrome (age 61 ± 10 years; BMI 31.7 ± 4.0 kg/m2) participated in a randomized, controlled, double-blind, cross-over trial with a 27-day intervention (5 g/day NWT-03) or placebo period, separated by two-to-eight weeks of washout. At the start and end of both periods, measurements were performed in the fasting state and 2 h following acute NWT-03 intake. Arterial stiffness was assessed by carotid-to-radial (PWVc-r), carotid-to-femoral pulse wave velocity (PWVc-f), and central augmentation index (CAIxHR75). Moreover, cardiometabolic markers were assessed.

RESULTS

Compared with control, longer-term NWT-03 supplementation did not affect fasting PWVc-r (0.1 m/s; -0.2 to 0.3; P = 0.715) or PWVc-f (-0.2 m/s; -0.5 to 0.1; P = 0.216). Fasting pulse pressure (PP) was however reduced by 2 mmHg (95% CI: -4 to 0; P = 0.043), but other fasting cardiometabolic markers were not affected. No effects were observed following acute NWT-03 intake at baseline. However, acute intake of NWT-03 after the intervention significantly lowered CAIxHR75 (-1.3%-point; -2.6 to -0.1; P = 0.037) and diastolic BP (-2 mmHg; -3 to 0; P = 0.036), but other cardiometabolic markers did not change.

CONCLUSION

Longer-term NWT-03 supplementation did not affect arterial stiffness, but modestly improved fasting PP in adults with metabolic syndrome. Acute intake of NWT-03 after the intervention also improved CAIxHR75 and diastolic BP.

TRIAL REGISTRATION

The study was registered at ClinicalTrials.gov as NCT02561663.

Evidence of Immunomodulatory Food-Protein Derived Peptides in Human Nutritional Interventions: Review on the Outcomes and Potential Limitations

The immune system is somehow related to all the metabolic pathways, in a bidirectional way, and the nutritional interventions affecting these pathways might have a relevant impact on the inflammatory status of the individuals. Food-derived peptides have been demonstrated to exert several bioactivities by in vitro or animal studies. Their potential to be used as functional food is promising, considering the simplicity of their production and the high value of the products obtained. However, the number of human studies performed until now to demonstrate effects in vivo is still scarce. Several factors must be taken into consideration to carry out a high-quality human study to demonstrate immunomodulatory-promoting properties of a test item. This review aims to summarize the recent human studies published in which the purpose was to demonstrate bioactivity of protein hydrolysates, highlighting the main results and the limitations that can restrict the relevance of the studies. Results collected are promising, although in some studies, physiological changes could not be observed. When responses were observed, they sometimes did not refer to relevant parameters and the immunomodulatory properties could not be clearly established with the current evidence. Well-designed clinical trials are needed in order to evaluate the role of protein hydrolysates in immunonutrition.

The Impact of Processing and Extraction Methods on the Allergenicity of Targeted Protein Quantification as Well as Bioactive Peptides Derived from Egg

This review article discusses advanced extraction methods to enhance the functionality of egg-derived peptides while reducing their allergenicity. While eggs are considered a nutrient-dense food, some proteins can cause allergic reactions in susceptible individuals. Therefore, various methods have been developed to reduce the allergenicity of egg-derived proteins, such as enzymatic hydrolysis, heat treatment, and glycosylation. In addition to reducing allergenicity, advanced extraction methods can enhance the functionality of egg-derived peptides. Techniques such as membrane separation, chromatography, and electrodialysis can isolate and purify specific egg-derived peptides with desired functional properties, improving their bioactivity. Further, enzymatic hydrolysis can also break down polypeptide sequences and produce bioactive peptides with various health benefits. While liquid chromatography is the most commonly used method to obtain individual proteins for developing novel food products, several challenges are associated with optimizing extraction conditions to maximize functionality and allergenicity reduction. The article also highlights the challenges and future perspectives, including optimizing extraction conditions to maximize functionality and allergenicity reduction. The review concludes by highlighting the potential for future research in this area to improve the safety and efficacy of egg-derived peptides more broadly.

Food protein-derived bioactive peptides for the management of nutrition related chronic diseases

Dietary intervention via modifications of dietary pattern or supplementations of naturally derived bioactive compounds has been considered as an efficient approach in management of nutrition related chronic diseases. Food protein-derived bioactive peptide is representative of natural compounds which show the potential to prevent or mitigate nutrition related chronic diseases. In the past decades, substantial research has been conducted concentrating on the characterization, bioavailability, and activity assessment of bioactive peptides. Although various activities of bioactive peptides have been reported, the activity testes of most peptides were only conducted in cells and animal models. Some clinical trials of bioactive peptides were also reported but only limited to antihypertensive peptides, antidiabetic peptides and peptides modulating blood lipid profile. Hereby, clinical evidence of bioactive peptides in management of nutrition-related chronic diseases is summarized in this chapter, which aims at providing implications for the clinical studies of bioactive peptides in the future.

Conventional and in silico approaches to select promising food-derived bioactive peptides: A review

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Seaweed and edible insects are considered new sources of bioactive peptides.

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Conventional approaches are necessary to validate the bioactivity of peptides.

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Bioinformatics tools accelerate the obtaining of bioactive peptides.

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The integrated approach is a promising strategy to obtain bioactive peptides.

The interest for food-derived bioactive peptides, either from common or unconventional sources, has increased due to their potential therapeutic effect against a wide range of diseases. The study of such bioactive peptides using conventional methods is a long journey, expensive and time-consuming. Hence, bioinformatic approaches, which can not only help to predict the formation of bioactive peptides from any known protein source, but also to analyze the protein structure/function relationship, have gained a new meaning in this scientific field. Therefore, this review aims to provides an overview of conventional characterization methods and the most recent advances in the field of in silico approaches for predicting and screening promising food-derived bioactive peptides.

An updated review on food-derived bioactive peptides: Focus on the regulatory requirements, safety, and bioavailability

Food-derived bioactive peptides (BAPs) are recently utilized as functional food raw materials owing to their potential health benefits. Although there is a huge amount of scientific research about BAPs' identification, purification, characterization, and physiological functions, and subsequently, many BAPs have been marketed, there is a paucity of review on the regulatory requirements, bioavailability, and safety of BAPs. Thus, this review focuses on the toxic peptides that could arise from their primary proteins throughout protein extraction, protein pretreatment, and BAPs' formulation. Also, the influences of BAPs' length and administration dosage on safety are summarized. Lastly, the challenges and possibilities in BAPs' bioavailability and regulatory requirements in different countries were also presented. Results revealed that the human studies of BAPs are essential for approvals as healthy food and to prevent the consumers from misinformation and false promises. The BAPs that escape the gastrointestinal tract epithelium and move to the stomach are considered good peptides and get circulated into the blood using different pathways. In addition, the hydrophobicity, net charge, molecular size, length, amino acids composition/sequences, and structural characteristics of BAPs are critical for bioavailability, and appropriate food-grade carriers can enhance it. The abovementioned features are also vital to optimize the solubility, water holding capacity, emulsifying ability, and foaming property of BAPs in food products. In the case of safety, the possible allergenic and toxic peptides often exhibit physiological functions and could be produced during the hydrolysis of food proteins. It was also noted that the production of iso-peptides bonds and undesirable Maillard reaction might occur during protein extraction, sample pretreatments, and peptide synthesis.

Beneficial Impact of Pork Dry-Cured Ham Consumption on Blood Pressure and Cardiometabolic Markers in Individuals with Cardiovascular Risk

Background: Evidence suggests that bioactive peptides reduce hypertension and affect certain metabolic pathways. Methods: Fifty-four volunteers with stage 1 prehypertension and/or hypercholesterolemia and/or basal glucose >100 mg/dL were recruited and randomized to pork dry-cured ham (n = 35) or cooked ham (placebo group; n = 19) for 28 days. After a wash-out period, meat products were changed for 28 additional days. Bioactive peptides composition and enzyme inhibitory activities of both products were characterized. Treatment comparisons for the main effects were made using a two (treatment) × two (times) repeated measures minus the effect of cooked ham (placebo). Results: 24 h mean systolic and diastolic pressures decreased up to 2.4 mmHg in the dry-cured ham period (treatment effect, p = 0.0382 y p = 0.0233, respectively) as well as the number of systolic pressure measures > 135 mmHg (treatment effect, p = 0.0070). Total cholesterol levels also decreased significantly after dry-cured ham intake (p = 0.049). No significant differences were observed between the two treatments for basal glucose, HOMA-IR index and insulin levels (p > 0.05). However, a significant rise of ghrelin levels was observed (treatment effect, p = 0.0350), while leptin plasma values slightly decreased (treatment effect, p = 0.0628). Conclusions: This study suggested the beneficial effects of regular dry-cured ham consumption on the improvement of systolic/diastolic blood pressures and facilitated the maintenance of metabolic pathways, which may be beneficial in the primary prevention of cardiovascular disease.

The Blood-Pressure-Lowering Effect of Food-Protein-Derived Peptides: A Meta-Analysis of Recent Clinical Trials

Although clinical trials of food-protein-derived peptides in the management of hypertension have been published, the results are controversial, which compelled us to conduct a meta-analysis to evaluate the pooled effect of peptide intervention. In this study, we searched for studies published between 2010 and 2021 and selected 12 eligible studies for a meta-analysis. The pooled effect of peptide intervention for systolic blood pressure (SBP) and diastolic blood pressure (DBP) was −3.28 mmHg (95% CI: −4.54, −2.03, p < 0.001) and −1.82 mmHg (95% CI: −3.46, −0.18, p = 0.03), respectively. Sub-group analyses showed that the reduction in BP in participants with higher basal BP (>140/85 mmHg) was greater (p = 0.007 for SBP and p = 0.01 for DBP), and the effect was stronger in Asian participants as compared with non-Asian participants (p = 0.01 for SBP and p = 0.04 for DBP). In addition, the effect of peptide intervention was more pronounced on SBP in participant groups with a lower ratio of male to female (≤0.5) as well as in participants with a mean age ≥50 years old. In conclusion, food-protein-derived antihypertensive peptides can significantly reduce BP in prehypertensive and hypertensive patients. Findings from this study could provide guidance for the design of clinical trials of antihypertensive peptides.

The effect of egg and its derivatives on vascular function: A systematic review of interventional studies

BACKGROUND & AIMS

Cardiovascular diseases (CVDs) are considered as a major cause of health loss for all regions of the world. Atherosclerosis is one of the most important underlying causes of CVDs. Vascular dysfunction is the primary marker of atherosclerosis. Various studies have investigated the effect of egg intake on CVDs. This study aimed to determine the effect of egg and its derivatives consumption on vascular function.

METHODS

Using a comprehensive search strategy, the searching was conducted on PubMed, Scopus and Google Scholar search engines resources (from inception up to Feb 2020). Intended exposure and outcome were egg or its derivatives intake, and vascular function measuring methods, respectively.

RESULTS

A total of 35 papers were found through search databases. Finally, seven trials were included, which were published between 2005 and 2018. Results showed that acute and chronic consumption of whole eggs did not have a significant adverse effect on flow-mediated dilatation (FMD). Also, lutein-enriched egg yolk and egg ovalbumin-derived protein hydrolysate did not have significant positive effects on FMD and pulse wave velocity (PWV), respectively. However, one month egg-yolk-derived phospholipid (PL) preparation intervention increased FMD by 3.4% (p < 0.05), and replacing a portion of a glucose challenge with whole eggs or egg whites improved postprandial FMD (p < 0.05).

CONCLUSIONS

We concluded that consumption of whole egg, despite being rich in cholesterol, has no adverse effect on vascular function, and even some of egg derivatives may improve vascular function. Further research is needed to justify the potential effects of egg or its derivatives on vascular function.

Effects of substituting eggs for high-carbohydrate breakfast foods on the cardiometabolic risk-factor profile in adults at risk for type 2 diabetes mellitus

Objectives

To assess effects of egg-based versus non-egg, higher-carbohydrate (CHO) breakfast meals on cardiometabolic health markers in overweight or obese adults with prediabetes and/or metabolic syndrome.

Methods

This randomized, crossover study included two 4-week dietary interventions, separated by a ≥4-week washout. Subjects incorporated into their habitual diets breakfast meals containing either 2 eggs/day for 6 days/week (Egg condition), or energy-matched, non-egg, higher-CHO-based foods (Non-Egg condition). Dietary intakes, insulin sensitivity, and other CHO metabolism indices, lipid biomarkers, high-sensitivity C-reactive protein, and blood pressures were measured.

Results

Thirty men and women with mean age 54.1 ± 1.9 years and body mass index 31.9 ± 0.7 kg/m² provided data. Neither diet condition significantly altered insulin sensitivity indices, but the homeostasis model assessment for insulin resistance was significantly (p = 0.028) higher after the Non-Egg vs. the Egg condition. Low-density lipoprotein cholesterol (LDL-C) was decreased from baseline (119 mg/dL) by 2.9 and 6.0% with Egg and Non-Egg breakfasts, respectively (p = 0.023). Systolic blood pressure was reduced from baseline (127 mm Hg) by 2.7 and 0.0% with Egg and Non-Egg, respectively (p = 0.018). Diet records indicated 149 kcal/day higher (p = 0.008) energy intake from non-study foods during the Egg condition; however, weight change from baseline did not differ between conditions.

Conclusion

Compared with the baseline diet, consumption of 12 eggs/week for 4 weeks at breakfast was associated with less reduction in LDL-C, and more lowering of systolic blood pressure, than observed with non-egg-based, energy-matched, control foods higher in CHO.