I-converting Enzyme Inhibitor Research Articles

From Sea to Lab: Angiotensin I-Converting Enzyme Inhibition by Marine Peptides—Mechanisms and Applications

To reveal potent ACE inhibitors, researchers screen various bioactive peptides from several sources, and more attention has been given to aquatic sources. This review summarizes the recent research achievements on marine peptides with ACE-inhibitory action and application. Marine peptides are considered excellent bioactives due to their large structural diversity and unusual bioactivities. The mechanisms by which these marine peptides inhibit ACE include competitive binding to ACEs’ active site, interfering with ACE conformational changes, and avoiding the identification of substrates. The unique 3D attributes of marine peptides confer inhibition advantages toward ACE activity. Because IC50 values of marine peptides’ interaction with ACE are low, structure-based research assumes that the interaction between ACE and peptides increased the therapeutic application. Numerous studies on marine peptides focused on the sustainable extraction of ACE-inhibitory peptides produced from several fish, mollusks, algae, and sponges. Meanwhile, their potential applications and medical benefits are worth investigating and considering. Due to these peptides exhibiting antioxidant, antihypertensive, and even antimicrobial properties simultaneously, their therapeutic potential for cardiovascular disease and other illnesses only increases. In addition, as marine peptides show better pharmacological benefits, they have increased absorption rates and low toxicity and could perhaps be modified for better stability and bioefficacy. Biotechnological advances in peptide synthesis and formulation have greatly facilitated the generation of peptide-based ACE inhibitors from marine sources, which subsequently offer new treatment models. This article gives a complete assessment of the present state of knowledge about marine organism peptides as ACE inhibitors. In addition, it emphasizes the relevance of additional investigation into their mechanisms of action, the optimization of manufacturing processes, and assessment in in vivo, preclinical, and clinical settings, underlining the urgency and value of this study. Using marine peptides for ACE inhibition not only broadens the repertory of bioactive compounds but also shows promise for tackling the global health burden caused by cardiovascular diseases.

Enhancing the nutritional and bioactive benefits of faba bean flour by combining preprocessing and thermoplastic extrusion: A comprehensive study on digestion-resistant peptides

This research assessed how three preprocessing techniques [soaking (S), soaking and reconstitution (SR), and soaking and dehulling (SD)] impact the protein digestibility and bioactivity of faba bean flours when combined with thermoplastic extrusion. Samples were compared against a control (C) of extruded faba bean flour without preprocessing. Applying preprocessing techniques followed by extrusion diminished antinutrient levels while enhancing protein hydrolysis and in vitro bioactivity in higher extent compared to C. Specifically, SD combined with extrusion was the most effective, achieving an 80% rate of protein hydrolysis and uniquely promoting the release of gastric digestion-resistant proteins (50-70 kDa). It also resulted in the highest release of small peptides (<3kDa, 22.51%) and free amino acids (15.50%) during intestinal digestion. Moreover, while all preprocessing techniques increased antioxidant (ABTS radical-scavenging), antidiabetic, and anti-hypertensive activities, SD extruded flour displayed the highest levels of dipeptidyl peptidase inhibition (DPP-IVi, IC50=13.20 µg/mL), pancreatic α-amylase inhibition (IC50=8.59 mg/mL), and angiotensin I-converting enzyme inhibition (ACEi, IC50=1.71 mg protein/mL). As a result, it was selected for further peptide and in silico bioactive analysis. A total of 24 bioactive peptides were identified in intestinal digests from SD extruded flour, all with potential DPP-IVi and ACEi activities, and six were also predicted as antioxidant peptides. VIPAGYPVAIK and GLTETWNPNHPEL were highlighted as resistant bioactive peptides with the highest antidiabetic and antioxidant potential. Our findings demonstrated that combining preprocessing (particularly SD) and thermoplastic extrusion enhances protein digestibility in faba beans and promotes the release of beneficial bioactive peptides in the intestine.

Characterization of four new cycloartane triterpenoids from Swietenia macrophylla and their angiotensin-I-converting enzyme inhibitory activity

Angiotensin I-converting enzyme (ACE) inhibition is currently a common method for the treatment and control of hypertension. In this study, four new (1–4) and one known (5) cycloartane triterpenoids were isolated from the leaves of Swietenia macrophylla by chromatographic techniques and identified by their spectroscopic data and a comprehensive comparison of published data. The triterpenoids were evaluated for their ACE inhibitory potential using in vitro inhibition assays and in silico methods. The inhibition assay and enzyme kinetics results showed that the most active triterpenoid, compound 4, inhibited ACE in a mixed-type manner with an IC50 value of 57.7 ± 6.07 μM. Computer simulations revealed that compound 4 reduces the catalytic efficiency of ACE by competitive insertion into the active pocket blocking the substrate, and the binding activity occurs mainly through hydrogen bonds and hydrophobic interactions. The study showed that S. macrophylla can be a source of bioactive material and the ACE inhibitory triterpenoid could be a potential antihypertensive agent.

Angiotensin I-converting enzyme (ACE) inhibition and biological activities of green and black tea samples from Azorean Camellia sinensis

Angiotensin I-converting enzyme (ACE) inhibition and biological activities of green and black tea samples from Azorean Camellia sinensis

Antibacterial and Angiotensin I-Converting Enzyme (ACE) Inhibition Activities of Essential Oil from Java Cardamom (Amomum compactum) Fruit.

The online version contains supplementary material available at 10.1007/s12088-023-01080-x.

Structure Characterization and Antihypertensive Effect of an Antioxidant Peptide Purified from Alcalase Hydrolysate of Velvet Antler.

Recently, interest in food-derived bioactive peptides as promising ingredients for the prevention and improvement of hypertension is increasing. The purpose of this study was to determine the structure and antihypertensive effect of an antioxidant peptide purified from velvet antler in a previous study and evaluate its potential as a various bioactive peptide. Molecular weight (MW) and amino acid sequences of the purified peptide were determined by quadrupole time-of-flight electrospray ionization mass spectroscopy. The angiotensin I-converting enzyme (ACE) inhibition activity of the purified peptide was assessed by enzyme reaction methods and in silico molecular docking analysis to determine the interaction between the purified peptide and ACE. Also, antihypertensive effect of the purified peptide in spontaneously hypertensive rats (SHRs) was investigated. The purified antioxidant peptide was identified to be a pentapeptide Asp-Asn-Arg-Tyr-Tyr with a MW of 730.31 Da. This pentapeptide showed potent inhibition activity against ACE (IC50 value, 3.72 μM). Molecular docking studies revealed a good and stable binding affinity between purified peptide and ACE and indicated that the purified peptide could interact with HOH2570, ARG522, ARG124, GLU143, HIS387, TRP357, and GLU403 residues of ACE. Furthermore, oral administration of the pentapeptide significantly reduced blood pressure in SHRs. The pentapeptide derived from enzymatic hydrolysate of velvet antler is an excellent ACE inhibitor. It might be effectively applied as an animal-based functional food ingredient.

Characterization and Potentiating Effects of the Ethanolic Extracts of the Red Seaweed Gracillaria sp. on the Activity of Carbenicillin against Vibrios.

β-lactam-resistant Vibrio strains are a significant clinical problem, and β-lactamase inhibitors are generally coadministered with β-lactam drugs to control drug-resistant bacteria. Seaweed is a rich source of natural bioactive compounds; however, their potential as β-lactamase inhibitors against bacterial pathogens remains unknown. Herein, we evaluated the potential β-lactamase inhibitory effect of the ethanolic extracts of the red seaweed Gracilaria sp. (GE) against four Vibrio strains. The minimum inhibitory concentration, half-maximal inhibitory concentration, checkerboard assay results, and time-kill study results indicate that GE has limited antibacterial activity but can potentiate the activity of the β-lactam antibiotic carbenicillin against Vibrio parahemolyticus and V. cholerae. We overexpressed and purified recombinant metallo-β-lactamase, VarG, from V. cholerae for in vitro studies and observed that adding GE reduced the carbenicillin and nitrocefin degradation by VarG by 20% and 60%, respectively. Angiotensin I-converting enzyme inhibition studies demonstrated that GE did not inhibit VarG via metal chelation. Toxicity assays indicated that GE exhibited mild toxicity against human cells. Through gas chromatography and mass spectrometry, we showed that GE comprises alkaloids, phenolic compounds, terpenoids, terpenes, and halogenated aromatic compounds. This study revealed that extracts of the red seaweed Gracillaria sp. can potentially inhibit β-lactamase activity.

Isolation, purification and bioactivity of ACE inhibitory peptides from peach kernel protein enzymatic hydrolysate

Peaches mainly produced in China are a source of food-derived proteins, but much of it is wasted. To make full use of the peaches and peaches related resources, we extracted proteins, including albumin, globulin, gliadin, and glutelin, from defatted Tibet wild peach kernels using Osborne method to study their angiotensin I-converting enzyme (ACE) inhibiting activity, which is an active ingredient for hypertension treatment. The different enzymatic products of these extracts were further separated by ultrafiltration membranes and reversed phase high-performance liquid chromatography (RP-HPLC). The component K2 originated from globulin hydrolysate by alcalase treatment showed the highest ACE inhibiting activity (IC50 0.78 mg/mL). Through further analyzing the Mass spectrometry results of K2 and searching the BIOEP database, the specific dipeptide AH (consisted of Ala and His) has been identified as the ACE inhibitory peptide, providing a potential for using Tibet peach kernel-derived peptides as an ingredient in functional food to control hypertension.

Design, synthesis and biological evaluation of ethyl-4,4,4-trifluoro-3-hydrazonobutanoate derivatives

The present study describes the synthesis and biological investigation of novel ethyl 4,4,4-trifluoro-3-hydrazonobutanoate derivatives, which were synthesized by condensation of commercially available hydrazines and ethyl 4,4,4-trifluorobut-2-ynoate. We explored the chemical space of these new fluorinated compounds to determine their antioxidant and antibacterial activities and their angiotensin I-converting enzyme (ACE) inhibition ability. The results indicated that the seven compounds synthesized revealed excellent antioxidant activity with inhibition values in the range of 67.83 ± 0.001-95.77 ± 0.05% at 2 µM. The compound 3g displayed the highest ACE inhibitory activity with an IC50 of 2.42 µM. The results revealed also that compound 3e was highly active against S. typhi, L. monocytogenes and K. pneumoniae. The docking of chemical compounds in the ACE active site showed possible inhibitory effect of all compounds on the catalytic activity of the enzyme, which would satisfactorily explain the anti-hypertensive effect of these compounds.

NPCdc, a synthetic natriuretic peptide, is a substrate to neprilysin and enhances blood pressure-lowering induced by enalapril in 5/6 nephrectomized rats

NPCdc is a natriuretic peptide synthesized from the amino acid sequence of the Crotalus durissus cascavella snake venom peptide, NP2Casca. NPCdc presents hypotensive and antioxidants effects. This study aimed to investigate in vivo whether angiotensin I-converting enzyme (ACE) inhibition would influence the impact of NPCdc in arterial pressure of rats submitted to 5/6 nephrectomy (Nx). Adult male Wistar rats following a 5/6 Nx were treated with enalapril (NxE group, 10 mg/kg/day, n = 9) or vehicle (Nx group, n = 8) for two weeks. On the 15th day after Nx, rats were anaesthetized and submitted to mean arterial pressure (MAP) determination before and after receiving two intravenous injections of saline (vehicle, n = 9) or NPCdc (0.3 μg/kg dissolved in saline, n = 18) separated by a 20-min interval. The kidneys were submitted to oxidative stress analysis. The basal MAP of the NxE group was nearly 20% lower (P < 0.05) than non-treated rats. NPCdc administration decreased the MAP in both groups; however, in the NxE group, the effects were observed only in the second injection. The peptide also decreased the NADPH oxidase activity in the renal cortex. Additionally, the hydrolysis of NPCdc by recombinant neprilysin (NEP) was monitored by mass spectrometry. NPCdc was cleaved by NEP at different peptides with an inhibition constant (Ki) of 1.5 μM, determined by a competitive assay using the NEP fluorescence resonance energy transfer (FRET) peptide substrate Abz-(d)Arg-Gly-Leu-EDDnp. Docking experiments confirmed the high affinity of NPCdc toward NEP. These findings provide new insights into the antihypertensive and antioxidant mechanism of action of NPCdc. Altogether, the results presented here suggest that NPCdc must be further studied as a potential therapy for cardiorenal syndromes.

Technological properties of chickpea (Cicer arietinum): Production of snacks and health benefits related to type-2 diabetes.

Chickpea (Cicer arietinum) is one of the most consumed pulses worldwide (over 2.3 million tons enter the world market annually). Some chickpea components have shown, in preclinical and clinical studies, several health benefits, including antioxidant capacity, and antifungal, antibacterial, analgesic, anticancer, antiinflammatory, and hypocholesterolemic properties, as well as angiotensin I-converting enzyme inhibition. In the United States, chickpea is consumed mostly in the form of hummus. However, the development of new products with value-added bioactivity is creating new opportunities for research and food applications. Information about bioactive compounds and functional properties of chickpea ingredients in the development of new products is needed. The objective of this review was to summarize available scientific information, from the last 15 years, on chickpea production, consumption trends, applications in the food industry in the elaboration of plant-based snacks, and on its bioactive compounds related to type 2 diabetes (T2D). Areas of opportunity for future research and new applications of specific bioactive compounds as novel food ingredients are highlighted. Research is key to overcome the main processing obstacles and sensory challenges for the application of chickpea as ingredient in snack preparations. The use of chickpea bioactive compounds as ingredient in food products is also a promising area for accessibility of their health benefits, such as the management of T2D.

Pepsin Hydrolysis of Orange By-Products for the Production of Bioactive Peptides with Gastrointestinal Resistant Properties

Recently, the use of bioactive compounds in improving human health has received more attention. The aim of the present study was to hydrolyze orange seed proteins using pepsin enzyme to obtain bioactive peptides as well as to study the stability of such activity after simulated gastrointestinal digestion conditions. The method was optimized using different enzyme concentrations from 1% to 3%, hydrolysis times between 2 and 5 h, and an optimal temperature of 33 °C. Biological activities including α-glucosidase inhibition, α-amylase inhibition, Angiotensin I-Converting Enzyme (ACEI) inhibition, ferric reducing antioxidant power, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity were evaluated. According to the results, a significant higher value of the biological activity (p < 0.05) was observed using an enzyme ratio of 0.03 E/S and hydrolysis time of 3.5 h. After size-exclusion chromatography separation, fractions 45–49 and 50–54 showed the highest biological roles such as antioxidant, ACEI inhibitory, and hypoglycemic. Fractions with the highest biological activity were purified using RP-HPLC and analyzed using nano-liquid chromatography and mass spectrometry. The results obtained after simulated gastrointestinal digestion indicated that peptide fractions obtained after chromatographic separation significantly maintain their activity.

Angiotensin I-Converting enzyme (ACE) inhibitory and dipeptidyl Peptidase-4 (DPP-Ⅳ) inhibitory activity of umami peptides from Ruditapes philippinarum

The functional activity of umami peptides after digestion is poorly known. We studied the dipeptidyl peptidase-4 (DPP- IV) and angiotensin I-converting enzyme (ACE) inhibition activity of 14 umami peptides from Ruditapes philippinarum in vivo and in vitro. GRVSNCAA (IC50 = 57.93 μmol/L) and TYLPVH (IC50 = 1.37 μmol/L) exhibited noncompetitive ACE inhibitory activity in vitro, and GPAGPAGPR showed DPP-IV inhibitory activity (IC50 = 160.5 μmol/L). The peptides also decreased systolic blood pressure and reduced the blood sugar level in the oral glucose tolerance test and the single blood pressure test. To understand the hypoglycemic and hypotensive mechanism of peptides, we conducted cell experiments with HepG2 and human umbilical vein endothelial cells. GRVSNCAA and TYLPVH significantly (p < 0.01) promoted nitric oxide secretion and reduced endothelin-1 production. GPAGPAGPR exerted hypoglycemic activity by increasing the content of hexokinase and pyruvate kinase.These results suggest that some umami peptides have the potential to provide human health benefits.

Synthesis, crystal structure, molecular docking studies and biological evaluation of aryl substituted dihydroisoquinoline imines as a potent angiotensin converting enzyme inhibitor

The different functionalities of imine group found in many compounds are of important biological activity. Since, the development of novel imines is biologically encouraged, this study aims to develop a straightforward synthesis pathway of dihydroisoquinoline imines that could reveal antihypertensive effects. Starting from 2-méthyl-1-phényl-2-propanol, four different dihydroisoquinoline imines compounds (2a-d) were obtained and their structures were analyzed by mass spectrum, elemental analysis and NMR spectral studies. The crystal structure of 2b was determined from single crystal X-ray diffraction data.The newly synthesized compounds were evaluated for angiotensin I-converting enzyme (ACE) inhibition, using an enzymatic in vitro assay. The results were compared to Captopril as a reference drug. Compounds 2a, 2b and 2d showed inhibition activity with IC50 values of 0.15, 0.13 and 0.40 mg/ml, respectively. The docking of chemical compounds in the ACE active site explained the higher inhibitory capability of compounds 2a and 2b on the catalytic activity of the enzyme, indicating a potential anti-hypertensive effect of these compounds.

Isolation and characterization of angiotensin I-converting enzyme (ACE-I) inhibition and antioxidant peptide from by-catch shrimp (Oratosquilla woodmasoni) waste

Abstract The aim was to drive the ACE-I inhibitory peptide from the dumped waste of O. woodmasoni muscle protein hydrolysate after 12 h of hydrolysis using thermolysin and pepsin. The degree of hydrolysis (DH) was observed till 12th hr and the maximum ACE-I inhibition activity was recorded in 2nd and 5th hr (73.51 ± 0.25% & 68.93 ± 0.23%) for thermolysin and pepsin respectively. Further, the higher active thermolysin hydrolysate was separated using ultrafiltration membrane unit and 10-3 kDa fraction showed chief ACE-I inhibition activity (IC50 value: 0.47 mg/mL). The active fraction was purified by consecutive chromatographic techniques using ion exchange chromatography (IEC) & gel filtration chromatography (GFC) using fast protein liquid chromatography (FPLC). Finally, the fraction TH1-A1 evaluated by ACE-I inhibition assay and showed 77.09 ± 2.18% inhibitions. The non-toxic peptide against MCF-7 cells was further characterized for functional properties at pH 2 to 10. The active purified fraction also exhibited antioxidant activity analyzed with various assays and found to have 5 amino acid sequence (Asn-Gly-Val-Ala-Ala) with molecular weight 431 Da through LC-MS/MS. In conclusion, the identified low molecular weight peptide from by catch O. woodmasoni waste has both ACE-I inhibition and antioxidant properties. Therefore, this peptide might be a better alternative nutraceutical and functional food after few more investigations.

Comparative Study of Angiotensin I-Converting Enzyme (ACE) Inhibition of Soy Foods as Affected by Processing Methods and Protein Isolation

Angiotensin converting enzyme (ACE) converts angiotensin I into the vasoconstrictor angiotensin II and eventually elevates blood pressure. High blood pressure is a major risk factor for heart disease and stroke. Studies show peptides present anti-hypertensive activity by ACE inhibition. During food processing and digestion, food proteins may be hydrolyzed and release peptides. Our objective was to determine and compare the ACE inhibitory potential of fermented and non-fermented soy foods and isolated 7S and 11S protein fractions. Soy foods (e.g., soybean, natto, tempeh, yogurt, soymilk, tofu, soy-sprouts) and isolated proteins were in vitro digested prior to the determination of ACE inhibitory activity. Peptide molecular weight distribution in digested samples was analyzed and correlated with ACE inhibitory capacity. Raw and cooked soymilk showed the highest ACE inhibitory potential. Bacteria-fermented soy foods had higher ACE inhibitory activity than fungus-fermented soy food, and 3 day germinated sprouts had higher ACE inhibition than those germinated for 5 and 7 days. The 11S hydrolysates showed higher ACE inhibitory capacity than 7S. Peptides of 1–4.5 kDa showed a higher contribution to reducing IC50. This study provides evidence that soy foods and isolated 7S and 11S proteins may be used as functional foods or ingredients to prevent or control hypertension.

Anti-Hypertensive Activity of Novel Peptides Identified from Olive Flounder (Paralichthys olivaceus) Surimi.

There is a growing interest in the health benefits of functional foods. A benefit that has been long sought is the control of hypertension through dietary approaches. Hypertension has been implicated as a risk factor for cardiovascular disease and is therefore of clinical significance. Here, we aim to demonstrate the antihypertensive activity of novel peptides derived from surimi, a functional food ingredient made from refined fish myofibrillar proteins. Three peptides, Ile-Val-Asp-Arg (IVDR), Trp-Tyr-Lys (WYK), and Val-Ala-Ser-Val-Ile (VASVI), were isolated from surimi made from the olive flounder (Paralichthys olivaceus). Our results show that IVDR, WYK, and VASVI exhibited high Angiotensin I-converting Enzyme (ACE) inhibition activity. These peptides are also shown to increase phosphorylation of protein kinase B (Akt) and endothelial nitric oxide synthase (eNOS), and significantly promote nitric oxide (NO) production in human umbilical vein endothelial cells. Oral administration of the peptides decreased blood pressure in spontaneously hypertensive rats (SHRs), thereby confirming that the peptides derived from surimi perform antihypertensive activity via the Akt/eNOS pathway. These results indicate that surimi made from P. olivaceus contains novel antihypertensive peptides that could be used to enhance the health benefits of food ingredients.

Angiotensin-converting enzyme inhibitors from Salvia elegans Vahl

Phytochemical research of the acetate and methanol extracts of the aerial parts (flowers, leaves and stems) of Salvia elegans allowed to obtain seventeen known compounds (1–17): three of them (4, 5, 14), had already been described for this species, while the others (1–3, 6–13, 15–17) are described for the first time for S. elegans. All isolated compounds were characterized using spectroscopic techniques and mass spectrometry and were evaluated in the Angiotensin I-converting enzyme (ACE) inhibition model, where the phenolic compounds (13, 14 and 15) had the same inhibitory effect as lisinopril at 0.02 mg/mL. The terpenes showed a moderate inhibitory capacity at a concentration of 0.2 mg/mL.

Efficacy of a Novel ACE-Inhibitory Peptide from Sargassum Maclurei in Hypertension and Reduction of Intracellular Endothelin-1.

Sargassum maclurei is a potential protein resource because of its high protein content and relatively balanced amino acid composition. To promote its usage in food, medical, or other industries, S. maclurei protein was hydrolyzed by pepsin and papain to obtain bioactive peptides. The S. maclurei protein hydrolysates (SMPHs) were purified using gel chromatography and reversed-phase high performance liquid chromatography (RP-HPLC), and 12 major fractions were obtained. The fraction D11 with the highest angiotensin I-converting enzyme (ACE) inhibition (61.59%, at 1 mg/mL) was subjected to liquid chromatography-mass spectrometry (LC-MS/MS) analysis, and about 17 peptides were identified, of which the RWDISQPY (1063.5 Da) was chosen to be synthesized based on in silico analysis. The RWDISQPY demonstrated high ACE inhibition ability (IC50: 72.24 μM) with competitive inhibition mode, and could effectively (p < 0.05) lower the systolic blood pressure and diastolic pressure of spontaneously hypertensive rats at the concentration of 150 mg/kg body weight. The results of the molecular docking simulation demonstrated that RWDISQPY could bind with the active sites S1 and S2 of ACE via short hydrogen bonds. Moreover, RWDISQPY showed acceptable endothelin-1 suppressing capacity (26.21% at 1.5 mg/mL). These results indicate that S. maclurei could be developed into functional foods such as antihypertensive products.

In Vitro Studies of Fermented Korean Chung-Yang Hot Pepper Phenolics as Inhibitors of Key Enzymes Relevant to Hypertension and Diabetes.

This study was investigated to evaluate the antioxidant activity, the angiotensin I-converting enzyme (ACE) inhibition effect, and the α-amylase and α-glucosidase inhibition activities of hot pepper water extracts both before and after their fermentation. The fermented pepper water extract (FP) showed significantly higher total phenol content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical inhibition effect, metal chelating activity and ACE inhibition activity compared to the non-fermented raw pepper water extract (RP) (p < 0.05). Meanwhile, the FP showed lower α-amylase and higher α-glucosidase inhibitory activities, but the RP showed similar levels of α-amylase and α-glucosidase inhibitory activities. Taken together, these results suggested that fermented pepper extract using water should be expected to have potentially inhibitory effects against both hyperglycemia and hypertension.