Bioavailability of angiotensin I converting enzyme inhibitory peptides

Bioactive peptides in dry-cured ham: A comprehensive review of preparation methods, metabolic stability, safety, health benefits, and regulatory frameworks

Dry-cured hams contain abundant bioactive peptides with significant potential for the development of functional foods. However, the limited bioavailability of food-derived bioactive peptides has hindered their utilization in health food development. Moreover, there is insufficient regulatory information regarding bioactive peptides and related products globally. This review summarizes diverse bioactive peptides derived from dry-cured ham and by-products originating from various countries and regions. The bioactivity, preparation techniques, bioavailability, and metabolic stability of these bioactive peptides are described, as well as the legal and regulatory frameworks in various countries. The primary objectives of this review are to dig deeper into the functionality of dry-cured ham and provide theoretical support for the commercialization of bioactive peptides from food sources, especially the dry-cured ham.

Exploration of nutritional and bioactive peptide properties in goat meat from various primal cuts during in vitro gastrointestinal digestion and absorption

OBJECTIVE

This research aims to explore the nutritional and bioactive peptide properties of goat meat taken from various primal cuts, including the breast, shoulder, rib, loin, and leg, to produce these bioactive peptides during in vitro gastrointestinal (GI) digestion and absorption.

METHODS

The goat meat from various primal cuts was obtained from Boer goats with an average carcass weight of 30±2 kg. The meat was collected within 3 h after slaughter and was stored at -80°C until analysis. A comprehensive assessment encompassed various aspects, including the chemical composition, cooking properties, in vitro GI digestion, bioactive characteristics, and the bioavailability of the resulting peptides.

RESULTS

The findings indicate that the loin muscles contain the highest protein and essential amino acid composition. When the meats were cooked at 70°C for 30 min, they exhibited distinct protein compositions and quantities in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile, suggesting they served as different protein substrates during GI digestion. Subsequent in vitro simulated GI digestion revealed that the cooked shoulder and loin underwent the most significant hydrolysis during the intestinal phase, resulting in the strongest angiotensin-converting enzyme (ACE) and dipeptidyl peptidase-IV (DPP-IV) inhibition. Following in vitro GI peptide absorption using a Caco-2 cell monolayer, the GI peptide derived from the cooked loin demonstrated greater bioavailability and a higher degree of ACE and DPP-IV inhibition than the shoulder peptide.

CONCLUSION

This study highlights the potential of goat meat, particularly cooked loin, as a functional meat source for protein, essential amino acids, and bioactive peptides during GI digestion and absorption. These peptides promise to play a role in preventing and treating metabolic diseases due to their dual inhibitory effects on ACE and DPP-IV.

Chicken Muscle-Derived ACE2-Upregulating Peptide VVHPKESF Reduces Blood Pressure Associated with the ACE2/Ang (1-7)/MasR Axis in Spontaneously Hypertensive Rats

SCOPE

This study aims to investigate the antihypertensive effect of four chicken muscle-derived angiotensin (Ang)-converting enzymes (ACE)-regulating peptides: Val-Arg-Pro (VRP, ACE inhibition), Leu-Lys-Tyr and Val-Arg-Tyr (LKY and VRY, ACE inhibition and ACE2 upregulation), and Val-Val-His-Pro-Lys-Glu-Ser-Phe (VVHPKESF [V-F], ACE2 upregulation) in spontaneously hypertensive rats.

METHODS AND RESULTS

Rats (12-14 weeks old) are grouped: 1) untreated, 2) VRP, 3) LKY, 4) VRY, and 5) V-F. Blood pressure (BP) is monitored using implantable telemetry technology. Over 18-day oral administration of 15 mg kg-1 body weight (BW) per day, only peptide V-F significantly (p < 0.05) reduces BP, decreases circulating Ang II, and increases ACE2 and Ang (1-7) levels, and enhances aortic expressions of ACE2 and Mas receptor (MasR). Peptide V-F also attenuates vascular inflammation (TNFα, MCP-1, IL-1α, IL-15, and cyclooxygenase 2 [COX2]) and vascular oxidative stress (nitrotyrosine). The gastrointestinal (GI)-degraded fragment of peptide V-F, Val-Val-His-Pro-Lys (VVHPK), is also an ACE2-upregulating peptide. Peptides VRP, LKY, and VRY do not reduce BP, possibly due to low bioavailability or other unknown reasons.

CONCLUSIONS

Peptide V-F is the first ACE2-upregulating peptide, purified and fractionated from food proteins based on in vitro ACE2 upregulation, that reduces BP associated with the activation of ACE2/Ang (1-7)/MasR axis; the N-terminal moiety VVHPK may be responsible for the antihypertensive effect of V-F.

Effects of diets supplemented with bioactive peptides on nutrient digestibility, immune cell responsiveness, and fecal characteristics, microbiota, and metabolites of adult cats

Bioactive peptides (BP) are recognized for their ability to function as antioxidants and maintain lipid stability. They may have positive health effects, including antihypertensive, anti-inflammatory, antimicrobial, osteoprotective, gut health, and immunomodulatory properties, but are poorly tested in cats. Our primary objective was to determine the apparent total tract digestibility (ATTD) of BP-containing kibble diets and assess how the fecal characteristics, metabolites, and microbiota were affected in adult cats. Our secondary objective was to test whether BP could impact blood oxidative stress markers and cytokine concentrations following transport stress. Twelve adult cats (4.83 ± 0.37 yr; 4.76 ± 0.14 kg) were used in a replicated 4 × 4 Latin square design to test four extruded kibble diets: Control (no BP), Chicken (4% chicken BP), Marine1 (2% marine BP), and Marine2 (4% marine BP). Each experimental period lasted 28 d, with a 20-d adaptation phase, 5 d for fecal collection, 2 d for blood collection, and 1 d for transport stress testing (driven in vehicle in individual carriers for 45 min). Salivary cortisol and blood oxidative stress markers and cytokines were measured after transport. Fecal microbiota data were evaluated using 16S rRNA gene amplicon sequencing and QIIME2. All other data were analyzed using the Mixed Models procedure of SAS, with P < 0.05 being considered significant and P < 0.10 considered trends. No differences were observed in animal health outcomes, with all cats remaining healthy and serum metabolites remaining within reference ranges. Cats fed the Marine2 diet had higher (P < 0.05) ATTD of dry matter (84.5% vs. 80.9%) and organic matter (88.3% vs. 85.8%) than those fed the control diet. The ATTD of protein and energy tended to be higher (P < 0.10) for cats fed the Marine2 diet. Fecal characteristics, metabolites, and bacterial alpha and beta diversity measures were not affected by treatment. However, the relative abundances of six bacterial genera were different (P < 0.05) and two bacterial genera tended to be different (P < 0.10) across treatments. Treatment did not alter salivary cortisol, blood oxidative stress markers, or blood cytokines after transport stress. Our data suggest that BP inclusion may increase nutrient digestibility and modify fecal microbiota and immune measures. More testing is required, however, to determine whether BP may provide additional benefits to cats.

Selection of goat β-casein derived ACE-inhibitory peptide SQPK and insights into its effect and regulatory mechanism on the function of endothelial cells

The angiotensin I-converting enzyme (ACE)-inhibitory peptide SQPK was selected by in silico digestion and virtual screening from goat β-casein, and its effect and regulatory mechanism on function of endothelial cells was further evaluated. The results showed that SQPK exhibited relatively good ACE inhibition capacity (IC50 = 452.7 μg/mL). Treatment with 25 μg/mL SQPK for 12 h significantly elevated nitric oxide (NO) production, stimulated eNOS expression (p < 0.05) and affected the transcriptomic profiling of EA. Hy926 cells. In particular, SQPK stimulated the expression of genes encoding inflammatory cytokines (CXCL1/2 and IL6) but depressed encoding mesenchymal markers (FN1 and CNN3). Furthermore, SQPK modified the expression of genes involved in endothelial-to-mesenchymal transition (EndMT). Therefore, the selected peptide SQPK may exert potential protective effects on the function of endothelial cells by inhibiting the EndMT.

Discovery and Characterization of a Dual-Function Peptide Derived from Bitter Gourd Seed Protein Using Two Orthogonal Bioassay-Guided Fractionations Coupled with In Silico Analysis

The hydrolysate of bitter gourd seed protein, digested by the combined gastrointestinal proteases (BGSP-GPs), exhibited the most potent inhibition on angiotensin-I-converting enzyme (ACE) with an IC50 value of 48.1 ± 2.0 µg/mL. Using two independent bioassay-guided fractionations, fraction F5 from reversed-phase chromatography and fraction S1 from strong cation exchange chromatography exhibited the highest ACE inhibitory (ACEI) activity. Three identical peptides were simultaneously detected from both fractions and, based on the in silico appraisal, APLVSW (AW6) was predicted as a promising ACEI peptide. Their dipeptidyl peptidase-IV (DPP4) inhibitory (DPP4I) activity was also explored. The IC50 values of AW6 against ACE and DPP4 were calculated to be 9.6 ± 0.3 and 145.4 ± 4.4 µM, respectively. The inhibitory kinetics and intermolecular interaction studies suggested that AW6 is an ACE competitive inhibitor and a DPP4 non-competitive inhibitor. The quantities of AW6 in BGSP-GP hydrolysate, fractions F5 and S1, were also analyzed using liquid chromatography-tandem mass spectrometry. Notably, AW6 could resist hydrolysis in the human gastrointestinal tract according to the result of the simulated gastrointestinal digestion. To the best of our knowledge, this is the first discovery and characterization of a dual-function (ACEI and DPP4I activities) peptide derived from bitter gourd seed protein.

Tandem mass tag-based quantitative proteomics analysis reveals the effects of the α-lactalbumin peptides GINY and DQW on lipid deposition and oxidative stress in HepG2 cells

The objective of this study was to investigate the mechanism by which the α-lactalbumin peptides Gly-Ile-Asn-Tyr (GINY) and Asp-Gln-Trp (DQW) ameliorate free fatty acid-induced lipid deposition in HepG2 cells. The results show that GINY and DQW reduced triglyceride, total cholesterol, and free fatty acid levels significantly in free fatty acid-treated HepG2 cells. Based on proteomic analysis, GINY and DQW alleviated lipid deposition and oxidative stress mainly through the peroxisome proliferator-activated receptor (PPAR) pathway, fatty acid metabolism, oxidative phosphorylation, and response to oxidative stress. In vitro experiments confirmed that GINY and DQW upregulated the mRNA and protein expression of fatty acid β-oxidation-related and oxidative stress-related genes, and downregulated the mRNA and protein expression of lipogenesis-related genes by activating peroxisome proliferator-activated receptor α (PPARα). Meanwhile, GINY and DQW reduced free fatty acid-induced lipid droplet accumulation and reactive oxygen species generation, and enhanced the mitochondrial membrane potential and ATP levels. Furthermore, GINY and DQW enhanced carnitine palmitoyl-transferase 1a (CPT-1a) and superoxide dismutase activities, and diminished acetyl-coenzyme A carboxylase 1 (ACC1) and fatty acid synthase (FASN) activities in a PPARα-dependent manner. Interestingly, GW6471 (a PPARα inhibitor) weakened the effects of GINY and DQW on the PPARα pathway. Hence, our findings suggest that GINY and DQW have the potential to alleviate nonalcoholic fatty liver disease by activating the PPARα pathway.

Assessment of angiotensin converting enzyme inhibitory activity and quality attributes of yoghurt enriched with Cinnamomum verum, Elettaria cardamomum, Beta vulgaris and Brassica oleracea

The new concept of functional foods has led to the varieties in the production of foods that provide not only basic nutrition, but can also warrant good health and longevity. This study deals with the production and evaluation of fortified yogurts' with Cinnamomum verum, Elettaria cardamomum, Beta vulgaris and Brassica oleracea. The qualitative and quantitative phytochemical analysis of above mentioned plant extracts before using them into the preparation of functional yoghurt was carried out. The sensory evaluation of enriched yogurts with plant extracts carried out using 9 point hedonic scale. Comparative analysis between enriched yogurts and plain yogurt was carried. The results indicated increase in ash contents, water holding capacity, titratable acidity, total soluble solids, total phenolic content, tannin content, and total flavonoid content in fortified yogurt as compared to plain yogurt. In addition to this fortified yogurts showed greater antioxidant and antibacterial activity in contrast to plain yogurt. However, moisture contents, pH and susceptibility to syneresis of yogurt decreases with the addition of plant extracts. Shelf life of plain and fortified yogurt was determined both at room and refrigerated temperature. The results revealed that shelf life of fortified yogurt was greater as compared to plain yogurt. In silico analysis was carried out by using the galaxy web software. The results indicated that bioactive compounds including ascorbic acid, sinapinic acid, cinnamaldehyde and linalool acetate present in the flavored yogurts binds with angiotensin converting enzyme. All enriched yogurts showed higher anti-Angiotensin converting enzyme activity as compared to plain-yogurt.

In Silico Prospecting for Novel Bioactive Peptides from Seafoods: A Case Study on Pacific Oyster (Crassostrea gigas)

Pacific oyster (Crassostrea gigas), an abundant bivalve consumed across the Pacific, is known to possess a wide range of bioactivities. While there has been some work on its bioactive hydrolysates, the discovery of bioactive peptides (BAPs) remains limited due to the resource-intensive nature of the existing discovery pipeline. To overcome this constraint, in silico-based prospecting is employed to accelerate BAP discovery. Major oyster proteins were digested virtually under a simulated gastrointestinal condition to generate virtual peptide products that were screened against existing databases for peptide bioactivities, toxicity, bitterness, stability in the intestine and in the blood, and novelty. Five peptide candidates were shortlisted showing antidiabetic, anti-inflammatory, antihypertensive, antimicrobial, and anticancer potential. By employing this approach, oyster BAPs were identified at a faster rate, with a wider applicability reach. With the growing market for peptide-based nutraceuticals, this provides an efficient workflow for candidate scouting and end-use investigation for targeted functional product preparation.

Valorisation of hazelnut by-products: current applications and future potential

Hazelnut is one of the most widely consumed nuts around the world. Considering the nutritional value of hazelnuts, a wide range of hazelnut-based food products are available in the market such as oil, chocolate, confectionery, etc. Nevertheless, the processing of hazelnuts generates a large number of by-products and waste. The most valuable by-products of the hazelnut industry are shell, skin, and meal. These by-products are rich in bioactive compounds, protein, dietary fibre, mono- and polyunsaturated fatty acids, vitamins, minerals, phytosterols, and squalene. The current utilisation of hazelnut by-products is mostly limited to animal feed supplementation of hazelnut meal and skin and use as a low-value heat source for the shells. However, disposing of these by-products or using them as a low-value heat source or animal feed supplementation results in significant waste of a natural resource rich in nutritional components. Consequently, valorising hazelnut by-products as bioactive ingredients in diverse fields such as food, pharmaceuticals and cosmetics has stimulated interest among scientists, producers, and consumers. This review provides an overview of current scientific knowledge about the main and most valuable hazelnut by-products and their actual valorisation, with a focus on their chemical composition to inspire new applications of these valuable resources and fully exploit their potential.

Molecular Interaction of Angiotensin-I Converting Enzyme (ACE) with Peptides Derived from Collagen Type i as Analogue for Tilapia By-Product Protein Precursor

The study aimed to investigate the molecular interaction of ACE-inhibitory peptides derived from collagen type I. Collagen type I alpha 1 and alpha 2 were used in this work was to analogue the tilapia by-product protein precursor for ACE-inhibitory peptides production. In silico production of ACE-inhibitory peptides derived collagen type I from BIOPEP was used to simulate peptide-ACE interaction using Autodock Vina. Most potent ACE-inhibitory tri-and di-peptides, Gly-Leu-Pro (GLP IC50 1.62 μM) and Cys-Phe (CF IC50 1.96 μM) derived alpha 1 and Leu-Gly-Pro (LGP IC50 0.72 μM), and Glu-Tyr (EY IC50 2.68 μM) derived alpha 2 were chosen from BIOPEP database. The hydrophobicity of the amino acids is suggested to contribute to bioactivity. These peptides inhibited the active sites of ACE at the C terminal residue. The zinc (II) interacted with all four peptides directly and indirectly. GLP and CY of alpha 1 could share a bond with His 383, His 387, and Glu 411 instead of directly binding to the zinc (II) atom. ACE has a zinc ion in its coordinates with His 383, His 387, and Glu 411. Alpha 2's LGP and EY were directly bound to Zinc (ii) atoms.

Current trends and perspectives on bioaccessibility and bioavailability of food bioactive peptides: in vitro and ex vivo studies

The bioaccessibility and bioavailability of food-derived bioactive compounds are important issues when assessing their in vivo physiological health-promoting effects. Food components such as proteins and peptides are exposed to different proteases and peptidases during gastrointestinal digestion and absorption. Different in vitro approaches have therefore been developed to evaluate the bioaccessibility and stability of bioactive peptides. The static simulated gastrointestinal digestion model (SGD) was widely reported to assess the bioaccessibility of bioactive peptides. On the other hand, although the dynamic SGD model may better simulate human digestion, it has rarely been explored in bioaccessibility studies of food bioactive peptides due to its high cost and lack of standardization. For bioavailability studies, the Caco-2 cell monolayer model has been used extensively for the assessment of food bioactive peptides. In fact, very few reports using alternative methods for determining transepithelial transport of bioactive peptides have been employed. In this sense, ex vivo tissue-based models such as the Ussing chamber and the everted sac gut have been used. Current evidence supports the fact that using SGD with cell-based models for evaluating the bioaccessibility, absorption, and bioavailability of food-derived bioactive peptides, is the most commonly used approach. Nevertheless, SGD with ex vivo tissue-based models such as the everted sac, remains to be further explored because it seems to be the model that better mimics the physiological process - it is also fast and inexpensive, and several compounds may be tested simultaneously. In the present review, we discuss information available on the different in vitro approaches for the determination of bioaccessibility and bioavailability of food-derived bioactive peptides with special emphasis on ex vivo tissue-based models such as the everted sac and the Ussing chamber models. © 2022 Society of Chemical Industry.

Inhibition kinetics, molecular docking, and stability studies of the effect of papain-generated peptides from palm kernel cake proteins on angiotensin-converting enzyme (ACE)

Three novel peptide sequences YGIKVGYAIP, GGIF, and GIFE from papain-generated protein hydrolysate of palm kernel cake proteins were used for stability study against ACE, ACE-inhibition kinetics, and molecular docking studies. Results showed that peptide YGIKVGYAIP was degraded, and its ACE-inhibitory activity decreased after 3 h pre-incubation with ACE, while peptides GGIF and GIFE were resistant. However, although the ACE-inhibitory activity of GIFE increased during this time, the ACE inhibitory activity of GGIF decreased after pre-incubation with ACE, indicating that peptide. YGIKVGYAIP and GGIF are substrate-type, whereas GIFE is a true-inhibitor type. Peptide YGIKVGYAIP showed the lowest K_i (0.054 mM) in the inhibition kinetics study compared to GGIF and GIFE, with K_i of 1.27 m M and 18 mM, respectively. In addition, YGIKVGYAIP revealed the lowest K_m and V_max and higher CE in different peptide concentrations, implying that the enzyme catalysis decreased, and peptides had some binding affinity to the enzyme in lower concentrations, which led to reduced catalytic ability. Furthermore, YGIKVGYAIP showed the lowest docking score of -14.733 and 21 interactions with tACE, while GGIF revealed the higher docking score of -8.006 with 15 interactions with tACE.

Effects of Thai native chicken breast meat consumption on serum uric acid level, biochemical parameters, and antioxidant activities in rats

This study aimed to evaluate the effect of a high protein diet comprising breast meat from commercial broiler (BR), Thai native (PD), and commercial broiler × Thai native crossbred (KKU-ONE) chicken on serum uric acid, biochemical parameters, and antioxidant activities in rats. Male Sprague–Dawley rats were divided into four groups. The control group received a standard chow diet, and the other three groups were fed a high protein diet (70% standard diet + 30% BR, PD, or KKU-ONE chicken breast) for five weeks. The PD- and KKU-ONE-fed rats had lower plasma total cholesterol and triglyceride levels than the control rats. A decrease in HDL-c was also observed in rats fed a diet containing BR. Liver weight, liver enzyme, plasma ALP, xanthine oxidase activity, serum uric acid, creatinine, superoxide production, and plasma malondialdehyde levels increased in BR-fed rats. The findings of this study might provide evidence to support the use of Thai native and Thai native crossbred chicken breast meat as functional foods.

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.

Extraction, Isolation and Identification of Low Molecular Weight Peptides in Human Milk

Human milk contains numerous free low molecular weight peptides (LMWPs), which may play an important role in infant health and growth. The bioactivities of LMWPs are determined by their structures, especially the amino acid sequences. In the present study, 81 human milk samples were collected and purified by cation-exchange solid-phase extraction (SPE). Ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) was used for the separation and detection of free LMWPs in human milk. A total of 56 LMWPs were identified and quantified. These LMWPs were mainly derived from 3 regions of β-casein, which were the amino acid fragments of 16–40, 85–110, and 205–226. The predominant LMWPs were RETIESLSSSEESITEYK, RETIESLSSSEESITEYKQKVEKVK, ETIESLSSSEESITEYK, TQPLAPVHNPIS, and QPLAPVHNPISV with molecular weights of 2247.9573, 2860.2437, 2091.8591, 1372.7666, and 1271.7212, respectively. The results indicated that the technique based on SPE and UPLC-QTOF-MS might greatly facilitate the analysis of LMWPs in human milk.

Do gluten peptides stimulate weight gain in humans?

Observations from animal and in vitro laboratory research, and anecdotal evidence, have led to the suggestion that gluten consumption stimulates weight gain by the presence of peptides expressing opioid activity. Another proposed mechanism is that gluten peptides decrease resting energy expenditure resulting in a positive energy balance. In order to induce such effects in vivo, intact food peptides must be absorbed in sufficient quantities, remain intact in the blood for sufficient time to have long‐lasting biological activity and bind to receptors involved in appetite, satiety and energy regulation. However, although peptides from food may pass from the intestine into the blood in extremely low quantities, they are generally rapidly degraded by plasma and vasculum‐bound aminopeptidases, resulting in very short half‐lives and loss of bioactivity. At present, gluten peptide sequences that influence regulators of energy metabolism have not been identified. Furthermore, data on the quantitative absorption of gluten peptides in the blood stream, their stability and lasting bioactivity are also lacking. Therefore, there is no evidence for proposed effects on driving appetite by the brain, nor on energy expenditure and weight gain. Furthermore, the level of overweight observed in various countries appears to be independent of the level of wheat consumption, and abundant observational evidence in humans shows that the levels of gluten consumption are neither related to daily calorie intake nor to BMI. This narrative review therefore discusses the proposed effects of gluten on bodyweight (BW) and putative biological mechanisms in the light of the current evidence.

Effect of Parmigiano Reggiano Consumption on Blood Pressure of Spontaneous Hypertensive Rats

In recent years, due to the significant increase in hypertension, peptides which are able to reduce blood pressure have gained special interest by scientific research and food industry. Several bioactive peptides with ascertained ACE-inhibitory activity have been found in Parmigiano Reggiano (PR) cheese and/or mixtures deriving from its digestion in vitro, and this may be predictive of itspotential antihypertensive effect in vivo. This study investigated the long-term effect of feeding (PR) cheese on blood pressure (BP) of spontaneously hypertensive rats (SHRs). A total of 30 male SHRs, 13 weeks old, were subdivided into 6 groups balanced for body weight and BP, to receive dailydietary supplementation with: 0.1–0.2–0.4–0.6 g PR/rat, captopril, and water. Systolic and diastolic BP were recorded every two weeks, for 10 weeks. Blood samples were collected at the end of the trial. Dietary integration with PR led to a transitory reduction in rats’ pressure in the first 35 days of treatment and pressure decreased in a dose-dependent manner. In the second part of the study, the beneficial effect of PR antihypertensive peptides may have been masked and reduced by the increase in BP of rats linked to the rise in age of animals. No PR derived peptides were detected in rats’ serum. Highlights: Parmigiano Reggiano (PR) cheese led to a transitory reduction in rats’ pressure in the first 35 days of treatment. This effect was PR dose dependent. The highest amounts of PR tested did not increase both systolic and diastolic blood pressures of hypertensive rats.

Current Trends and Applications of Food-derived Antihypertensive Peptides for the Management of Cardiovascular Disease

Abstract:

Food derived Antihypertensive peptides is considered as a natural supplement for controlling the hypertension. Food protein not only serve as a macronutrient but also act as raw material for biosynthesis of physiologically active peptides. Food sources like milk and milk products, animal protein such as meat, chicken, fish, eggs and plant derived proteins from soy, rice, wheat, mushroom, pumpkins contain high amount of antihypertensive peptides. The food derived antihypertensive peptides has ability to supress the action of rennin and Angiotesin converting enzyme (ACE) which is mainly involved in regulation of blood pressure by RAS. The biosynthesis of endothelial nitric oxide synthase is also improved by ACE inhibitory peptides which increase the production of nitric oxide in vascular walls and encourage vasodilation. Interaction between the angiotensin II and its receptor is also inhibited by the peptides which help to reduce hypertension. This review will explore the novel sources and applications of food derived peptides for the management of hypertension.

Antioxidant and Antimicrobial Peptides Derived from Food Proteins

Recently, the demand for food proteins in the market has increased due to a rise in degenerative illnesses that are associated with the excessive production of free radicals and the unwanted side effects of various drugs, for which researchers have suggested diets rich in bioactive compounds. Some of the functional compounds present in foods are antioxidant and antimicrobial peptides, which are used to produce foods that promote health and to reduce the consumption of antibiotics. These peptides have been obtained from various sources of proteins, such as foods and agri-food by-products, via enzymatic hydrolysis and microbial fermentation. Peptides with antioxidant properties exert effective metal ion (Fe2+/Cu2+) chelating activity and lipid peroxidation inhibition, which may lead to notably beneficial effects in promoting human health and food processing. Antimicrobial peptides are small oligo-peptides generally containing from 10 to 100 amino acids, with a net positive charge and an amphipathic structure; they are the most important components of the antibacterial defense of organisms at almost all levels of life-bacteria, fungi, plants, amphibians, insects, birds and mammals-and have been suggested as natural compounds that neutralize the toxicity of reactive oxygen species generated by antibiotics and the stress generated by various exogenous sources. This review discusses what antioxidant and antimicrobial peptides are, their source, production, some bioinformatics tools used for their obtainment, emerging technologies, and health benefits.

Antihypertensive activity of orally consumed ACE-I inhibitory peptides

Food proteins are sources for ACE-I inhibitory peptides that can be extracted by enzymatic hydrolysis exhibiting anti-hypertensive activity. However, these peptides are prone to further degradation by gastrointestinal enzymes during oral consumption. Bio-activity of these peptides is dependent on the resultant peptide post gastrointestinal digestion. To exhibit the bio-activity, they need to be absorbed in intact form. Although studies suggest di and tri-peptides show better ACE-I inhibitory activity, few peptides show altered IC₅₀ values under simulated gastrointestinal digestion. Moreover, ACE-I inhibitory peptides with low IC₅₀ values have not shown effective anti-hypertensive activity in spontaneously hypertensive rats when administered orally. Few ACE-I inhibitory peptides have reported effective reduction in systolic blood-pressure when administered through intravenously. During oral consumption of such peptides, the actual peptide sequence responsible for reducing blood-pressure is a result of breakdown in gastrointestinal tract. The fate of targeted peptides during digestion depends on amino acid sequence of the protein containing the specific site for cleavage where the action of digestive enzymes takes place. Therefore, this review attempts to explain the factors that affect the anti-hypertensive activity of ACE-I inhibitory peptides during oral consumption. It also highlights subsequent absorption of ACE-I inhibitory peptides after gastrointestinal digestion.

The impact of collagen protein ingestion on musculoskeletal connective tissue remodeling: a narrative review

Collagen is the central structural component of extracellular connective tissue, which provides elastic qualities to tissues. For skeletal muscle, extracellular connective tissue transmits contractile force to the tendons and bones. Connective tissue proteins are in a constant state of remodeling and have been shown to express a high level of plasticity. Dietary-protein ingestion increases muscle protein synthesis rates. High-quality, rapidly digestible proteins are generally considered the preferred protein source to maximally stimulate myofibrillar (contractile) protein synthesis rates. In contrast, recent evidence demonstrates that protein ingestion does not increase muscle connective tissue protein synthesis. The absence of an increase in muscle connective tissue protein synthesis after protein ingestion may be explained by insufficient provision of glycine and/or proline. Dietary collagen contains large amounts of glycine and proline and, therefore, has been proposed to provide the precursors required to facilitate connective tissue protein synthesis. This literature review provides a comprehensive evaluation of the current knowledge on the proposed benefits of dietary collagen consumption to stimulate connective tissue remodeling to improve health and functional performance.

Novel Angiotensin-I Converting Enzyme Inhibitory Peptides Isolated From Rice Wine Lees: Purification, Characterization, and Structure-Activity Relationship

The bioactive peptides that can inhibit angiotensin-I converting enzyme (ACE, EC. 3. 4.15.1) are considered as possible cures of hypertension. Food-derived angiotensin-I converting enzyme inhibitory (ACEi) peptides have gained more attention because of their reduced side effects. In this study, we reported the method for purifying ACEi peptides from the lees of traditional Chinese rice wine and evaluated the product's biochemical properties. After three steps of reversed-phase high-performance liquid chromatography (RP-HPLC), for the first time, we isolated, purified, and identified two novel peptides: LIIPQH and LIIPEH, both of which showed strong ACEi activity (IC₅₀-values of 120.10 ± 9.31 and 60.49±5.78 μg/ml, respectively). They were further categorized as mixed-type ACE inhibitors and were stable against both ACE and gastrointestinal enzymes during in vitro digestion. Together, these results suggest that the rice wine lees that produced as a by-product during rice wine production can be utilized in various fields related to functional foods and antihypertensive medicine.

Advancement and prospects of production, transport, functional activity and structure-activity relationship of food-derived angiotensin converting enzyme (ACE) inhibitory peptides

Food-derived antihypertensive peptides have attracted increasing attention in functional foods for health promotion, due to their high biological activity, low toxicity and easy metabolism in the human body. Angiotensin converting enzyme (ACE) is a key enzyme that causes the increase in blood pressure in mammals. However, few reviews have summarized the current understanding of ACE inhibitory peptides and their knowledge gaps. This paper focuses on the food origins and production methods of ACE inhibitory peptides. Compared with conventional methods, the advanced technologies and emerging bioinformatics approaches have recently been applied for efficient and targeted release of ACE inhibitory peptides from food proteins. Furthermore, the transport and underlying mechanisms of ACE inhibitory peptides are emphatically described. Molecular modeling and the Michaelis-Menten equation can provide information on how ACE inhibitors function. Finally, we discuss the structure-activity relationships and other bio-functional properties of ACE inhibitory peptides. Molecular weight, hydrophobic amino acid residues, charge, amino acid composition and sequence (especially at the C-terminal and N-terminal) have a significant influence on ACE inhibitory activity. Some studies are required to increase productivity, improve bioavailability of peptides, evaluate their bio-accessibility and efficiency on reducing blood pressure to provide a reference for the development and application of health products and auxiliary treatment drugs.

Hypotensive peptides derived from plant proteins

Hypertension is a risk factor for arteriosclerosis development and is recognized as a silent killer. Certain processed food materials, digested by protease or through the use of fermentation, have shown exertion of hypotensive effects in human clinical or animal studies, and hypotensive peptides were isolated from them. This review discusses the hypotensive peptides derived from plant proteins, such as grain, soy, vegetables, and seaweeds, and their hypotensive mechanisms. Although angiotensin I-converting enzyme (ACE) inhibition is often noted as one of the mechanisms that may exert antihypertensive effects, ACE inhibitory activity measured by in vitro studies is not associated with the actual hypotensive effect. Thus, this review only highlights the peptide hypotensive effect determined by in vivo studies. This review also discusses the tendency of the amino acid sequence of ACE-inhibitory hypotensive peptides and the possible additional effects of hypotensive peptides independent of ACE inhibition.

The necessity of enzymatically hydrolyzing walnut protein to exert antihypertensive activity based on in vitro simulated digestion and in vivo verification

Since not all proteins are suitable for preparing bioactive peptides by enzymatic degradation, the purpose of this study is to evaluate the necessity of walnut protein (WP) enzymolysis to exert its potential antihypertensive activity. Five proteases were used to hydrolyze WP to produce WP hydrolysate (WPH) enzymatically. The angiotensin-I-converting enzyme (ACE) inhibitory activity of WP and WPH before and after simulated digestion in vitro was measured, and the antihypertensive effect was evaluated in vivo. The results showed that after simulated digestion in vitro, the ACE inhibitory activity of WP digests (44.85%) was not significantly different from that of WPH digests (p > 0.05). In vivo experimental results showed that both WP and WPH had significant blood pressure lowering effects in the acute and long-term administrative experiments. The mechanism of its antihypertensive activities was regulating the balance of the renin-angiotensin-aldosterone system and the kallikrein-kinin system by inhibiting ACE activities in tissues and regulating the level of endothelium-derived vasoconstrictor factors and relaxing factors in serum. It seems unnecessary to carry out enzymatic hydrolysis to produce walnut peptides with antihypertensive activity.

Blood pressure and sugar regulating potentials of Anarcadium occidentale nut globulin and albumin hydrolysates

Several novel functional peptides have been successfully extracted from plant storage proteins. This study investigated the degree of hydrolysis, peptide yield, amino acid constituents, angiotensin converting enzyme (ACE), alpha amylase inhibitory and in vitro antioxidant activities of cashew (Anarcardium occidentale) nut proteins (CNP) hydrolysates (CNPHs). Cashew nut proteins (albumin and globulin) were hydrolysed using pancreatin, Alcalase and trypsin. The peptide yield and degree of hydrolysis (DH) of CNP by pancreatin (75.69 ± 0.84%; 37.39 ± 0.31) was significantly higher than those by Alcalase (61.67 ± 0.55%; 23.87 ± 0.23) and trypsin (43.33 ± 0.45%; 11 ± 0.15). The inhibition of ACE by albumin and globulin hydrolysates was concentration dependent. At 1.2 mg/mL, ACE-inhibitory activity of pancreatic cashew nut globulin (CNGH) hydrolysate (51.65 ± 1.2%) was significantly higher than those of Alcalase (34.603 ± 0.65%) and tryptic (29.92 ± 0.73%) CNGHs. Cashew nut albumin hydrolysate (CNAH) demonstrated concentration-dependent alpha-amylase inhibition (IC50 0.17 ± 0.02-0.41 ± 0.021 mg/mL). The order of inhibition was tryptic > Alcalase > pancreatic CNAHs. The pancreatic hydrolysates of both albumin and globulin fractions displayed the highest DPPH antioxidant activity, while pancreatic CNAH was the most potent superoxide anion scavenger. These findings therefore posit that cashew nut globulin and albumin hydrolysates are laden with useful bioactive peptides that may be further explored for regulation of blood pressure and sugar in hypertensive and diabetic in vivo models.

The structural reconformation of peptides in enhancing functional and therapeutic properties: Insights into their solid state crystallizations

Therapeutic peptides derived proteins with alpha-reconformation states like antibody shape have shown potential effects in combating terrible diseases linked with earlier signs of angiogensis, mutagenesis and transgenesis. Alpha reconformation in material design refers to the folding of the peptide chains and their transitions under reversible chemical bonds of disulfide chemical bridges and further non-covalence lesions. Thus, the rational design of signal peptides into alpha-helix is intended in increasing the defending effects of peptides into cores like adjuvant antibiotic and/or vaccines. Thereby, the signal peptides are able in displaying multiple eradicating regions by changing crystal-depositions and deviation angles. These types of molecular structures could have multiple advantages in tracing disease syndromes and impurities by increasing the host defense against the fates of pathogens and viruses, eventually leading to the loss in signaling by increasing peptide susceptibility levels to folding and unfolding and therefore, formation of transgenic peptide models. Alpha reconformation peptides is aimed in triggering as well as other regulatory functions such as remodulating metabolic chain disorders of lipolysis and glucolysis by increasing the insulin and leptin resistance for best lipid storages and lipoprotein density distributions.

Activity and bioavailability of food protein-derived angiotensin-I-converting enzyme-inhibitory peptides

Angiotensin-I-converting enzyme (ACE) inhibitory peptides are able to inhibit the activity of ACE, which is the key enzymatic factor mediating systemic hypertension. ACE-inhibitory peptides can be obtained from edible proteins and have the function of antihypertension. The amino acid sequences and the secondary structures of ACE-inhibitory peptides determine the inhibitory activities and stability. The resistance of ACE-inhibitory peptides to digestive enzymes and peptidase affect their antihypertensive bioactivity in vivo. In this paper, the mechanism of ACE-inhibition, sources of the inhibitory peptides, structure-activity relationships, stability during digestion, absorption and transportation of ACE-inhibitory peptides, and consumption of ACE-inhibitory peptides are reviewed, which provide guidance to the development of new functional foods and production of antihypertensive nutraceuticals and pharmaceuticals.

Peptides in Colorectal Cancer: Current State of Knowledge

Colorectal cancer (CRC) is the second most deadly and the third most commonly diagnosed cancer in the world. CRC treatment is mainly based on surgery, chemotherapy, and even though the probability of complications after surgery is very low, chemo drugs affect the patient's quality of life. Multiple studies have shown a strong correlation between diet and the onset and progression of CRC. Thus, the consumption of dietary nutraceuticals for its treatment and prevention has been suggested as a promising option. Peptides have increasingly become of interest in human health due to their antioxidant, antihypertensive, and anticancer potential. In recent years, there have been extensive reports on peptides with anti-tumor activity, and some studies suggest that peptides modulate cell proliferation, evasion of cell death, and metastasis in malignant cells. Plant-derived peptides such as soybean, bean, and rice have received main attention. In this review, we show evidence of several mechanisms through which bioactive peptides exert anti-tumor activity over in vitro and in vivo CRC models. We also report the current status of major production techniques, as well as limitations and future perspectives. Graphical Abstract.

Potential of Plant Proteins Digested In Silico by Gastrointestinal Enzymes as Nutritional Supplement for COVID-19 Patients

Currently, no specific drug and vaccine are available for the new coronavirus SARS-CoV-2, and nutritional supplementation should be helpful. This study tried to provide reference for protein supplementation. Specifically, in silico method was employed to simulate protein degradation by gastrointestinal enzymes and to produce a large number of active peptides, then, the binding ability of these peptides to SARS-CoV-2 spike protein receptor-binding domain (RBD) was evaluated. The results showed that wheat-derived alpha/beta-gliadin, oat-derived avenin, and ribulose bisphosphate carboxylase small chain of different origin could be good protein source in generating potent binders to SARS-CoV-2 spike RBD. In addition, some high-affinity oligopeptides (such as PISCR, VQVVN, PQQQF, etc.) were identified as potential binders of SARS-CoV-2 spike RBD. In summary, a number of plant proteins could be helpful for COVID-19 patients when supplemented with these proteins, the identified oligopeptides could be used as lead compound to design potential entry inhibitors against SARS-CoV-2.

Electric field effects on proteins - Novel perspectives on food and potential health implications

Electric fields (EF) technologies have been establishing a solid position in emergent food processing and have seen as serious alternatives to traditional thermal processing. During the last decades, research has been devoted to elucidation of technological and safety issues but also fundamental aspects related with interaction of electric fields (EF) with important macromolecules, such as proteins. Proteins are building blocks for the development of functional networks that can encompass health benefits (i.e. nutritional and bioactive properties) but may be also linked with adverse effects such as neurodegenerative diseases (amyloid fibrils) and immunological responses. The biological function of a protein depends on its tridimensional structure/conformation, and latest research evidences that EF can promote disturbances on protein conformation, change their unfolding mechanisms, aggregation and interaction patterns. This review aims at bringing together these recent findings as well as providing novel perspectives about how EF can shape the behavior of proteins towards the development of innovative foods, aiming at consumers' health and wellbeing.

Metabolomics profiling in hypertension and blood pressure regulation: a review

Hypertension is a chronic health condition in which blood pressure is usually elevated beyond normal levels. It can progress with serious complications if left undetected and untreated. Incidence of hypertension is on the increase worldwide with debilitating consequences on the health systems of many countries. It is a multifactorial disorder that requires a multi-pronged approach to address it. One such approach is the use of metabolomics or metabolite profiling to understand its underlying cause and possibly control it. Changes in metabolites profiles have been used to accurately predict so many disease conditions in addition to identifying possible biomarkers and pathways associated in their pathogenicity. This will enable their early detection, diagnosis and treatment as well as likely complications that may arise and also assist in development of biomarkers for clinical uses. The objective of this review therefore is to present some of the current knowledge on the application of metabolomics profiling in hypertension and blood pressure control.

Cardiovascular Active Peptides of Marine Origin with ACE Inhibitory Activities: Potential Role as Anti-Hypertensive Drugs and in Prevention of SARS-CoV-2 Infection

Growing interest in hypertension-one of the main factors characterizing the cardiometabolic syndrome (CMS)-and anti-hypertensive drugs raised from the emergence of a new coronavirus, SARS-CoV-2, responsible for the COVID19 pandemic. The virus SARS-CoV-2 employs the Angiotensin-converting enzyme 2 (ACE2), a component of the RAAS (Renin-Angiotensin-Aldosterone System) system, as a receptor for entry into the cells. Several classes of synthetic drugs are available for hypertension, rarely associated with severe or mild adverse effects. New natural compounds, such as peptides, might be useful to treat some hypertensive patients. The main feature of ACE inhibitory peptides is the location of the hydrophobic residue, usually Proline, at the C-terminus. Some already known bioactive peptides derived from marine resources have potential ACE inhibitory activity and can be considered therapeutic agents to treat hypertension. Peptides isolated from marine vertebrates, invertebrates, seaweeds, or sea microorganisms displayed important biological activities to treat hypertensive patients. Here, we reviewed the anti-hypertensive activities of bioactive molecules isolated/extracted from marine organisms and discussed the associated molecular mechanisms involved. We also examined ACE2 modulation in sight of SARS2-Cov infection prevention.

Current Evidence on the Bioavailability of Food Bioactive Peptides

Food protein-derived bioactive peptides are recognized as valuable ingredients of functional foods and/or nutraceuticals to promote health and reduce the risk of chronic diseases. However, although peptides have been demonstrated to exert multiple benefits by biochemical assays, cell culture, and animal models, the ability to translate the new findings into practical or commercial uses remains delayed. This fact is mainly due to the lack of correlation of in vitro findings with in vivo functions of peptides because of their low bioavailability. Once ingested, peptides need to resist the action of digestive enzymes during their transit through the gastrointestinal tract and cross the intestinal epithelial barrier to reach the target organs in an intact and active form to exert their health-promoting properties. Thus, for a better understanding of the in vivo physiological effects of food bioactive peptides, extensive research studies on their gastrointestinal stability and transport are needed. This review summarizes the most current evidence on those factors affecting the digestive and absorptive processes of food bioactive peptides, the recently designed models mimicking the gastrointestinal environment, as well as the novel strategies developed and currently applied to enhance the absorption and bioavailability of peptides.

Soy bioactive peptides and the gut microbiota modulation

The balance of protein, carbohydrate, and fat affect the composition and functions of the gut microbiota. The complexities involved thereof require insights into the roles and impacts of individual dietary components due to the difficulty of defining such in a group of others. Peptides and proteins from several animal and plant sources have been widely explored in relation to the gut microbiome modulation, but the effects of soy peptides and other soy derivatives on the gut microbiota are largely unexplored. This piece considered an overview of the production and interventions of soy bioactive peptides on gut, as they affect the composition and functions of the gut microorganisms. A mini review on the production of soy protein hydrolysates/peptides and highlights of the most recent knowledge regarding their physiological effects on host's gut microbiota cum health were investigated. Overall deductions and research gaps were critically evaluated for futuristic interventions and relevance. Key points • Diet affects the composition of gut microorganisms. • Modulation of the gut microbiota by soy biopeptides is described. • Critical deductions on personal and commercial use are provided.

Chocolate desserts with ricotta hydrolysates: In vitro study of inhibitory activity against angiotensin-converting enzyme and cholinesterase

Food can be a source of valuable peptides with high bioactivity, which regulate the functioning of cardiovascular and nervous systems. The aim of the study was to evaluate the possibility of usage ricotta after hydrolysis to obtain innovative chocolate desserts. It was shown that the hydrolysis of whey proteins in ricotta had insignificant effect on the texture indices of the products, except gumminess, as it declined to 16% in ricotta samples and to 7% in case of chocolate dessert samples. Confirmed was that the hydrolysis of the ricotta affected the activity of prepared desserts with respect to cholinesterases and angiotensin-converting enzyme. Enzymatic hydrolysate of ricotta may be consider as a semifinished product of high functional activity, and its further application in dessert production allows to provide novel prohealth new products. PRACTICAL APPLICATION: Study results indicate new feasibilities of ricotta application as functional ingredient of new products--chocolate desserts. The results show that ricotta after the stage of enzyme hydrolysis of proteins might have noticeable effect on product functionality. A measurable benefit for the consumer is the receipt of a new product with favorable health-promoting properties, and for the entrepreneur new possibilities to expand the range of functional products. Moreover, described technology allows to use dairy byproducts for new products developments, such as chocolate desserts, due to sustainability development strategy.