Angiotensin-converting Enzyme Inhibition Research Articles

ACE2 activation alleviates sepsis-induced cardiomyopathy by promoting MasR-Sirt1-mediated mitochondrial biogenesis

Sepsis-induced cardiomyopathy (SIC), caused by a dysregulated host response to infection, is a major contributor to high mortality. Angiotensin-converting enzyme 2 (ACE2), a crucial component of the renin-angiotensin system (RAS), has protective effects against several cardiovascular diseases, such as myocardial infarction and heart failure. However, the role of ACE2 in the pathogenesis of SIC and underlying mechanisms remain unknown. The present study was designed to examine the effects of ACE2 activation or inhibition on SIC in C57BL/6 mice. The ACE2 activator diminazene aceturate (DIZE) and ACE2 inhibitor MLN-4760 were applied for treatment. Myocardial function, inflammatory response, oxidative stress, apoptosis and mitochondrial biogenesis were investigated. Major assays were echocardiography, H&E staining, immunofluorescence staining, DHE staining, TUNEL staining, Western blot, qPCR analysis, ELISA and corresponding kits. We confirmed that ACE2 was markedly downregulated in septic heart tissues. Pharmacological activation of ACE2 by DIZE ameliorated cecal ligation puncture (CLP)-induced mortality, cardiac dysfunction, inflammatory response, oxidative stress and the cardiomyocyte apoptosis by promoting MasR-Sirt1-mediated mitochondrial biogenesis. In contrast, SIC was aggravated via inhibiting MasR-Sirt1-mediated mitochondrial biogenesis by the use of ACE2 inhibitor MLN-4760. Consequently, activation of ACE2 may protect against SIC by promoting MasR-Sirt1-mediated mitochondrial biogenesis.

Lavandula pedunculata Polyphenol-Rich Extracts Obtained by Conventional, MAE and UAE Methods: Exploring the Bioactive Potential and Safety for Use a Medicine Plant as Food and Nutraceutical Ingredient.

Nowadays, plant-based bioactive compounds (BCs) are a key focus of research, supporting sustainable food production and favored by consumers for their perceived safety and health advantages over synthetic options. Lavandula pedunculata (LP) is a Portuguese, native species relevant to the bioeconomy that can be useful as a source of natural BCs, mainly phenolic compounds. This study compared LP polyphenol-rich extracts from conventional maceration extraction (CE), microwave and ultrasound-assisted extraction (MAE and UAE). As a result, rosmarinic acid (58.68-48.27 mg/g DE) and salvianolic acid B (43.19-40.09 mg/g DE) were the most representative phenolic compounds in the LP extracts. The three methods exhibited high antioxidant activity, highlighting the ORAC (1306.0 to 1765.5 mg Trolox equivalents (TE)/g DE) results. In addition, the extracts obtained with MAE and CE showed outstanding growth inhibition for B. cereus, S. aureus, E. coli, S. enterica and P. aeruginosa (>50%, at 10 mg/mL). The MAE extract showed the lowest IC50 (0.98 mg DE/mL) for angiotensin-converting enzyme inhibition and the best results for α-glucosidase and tyrosinase inhibition (at 5 mg/mL, the inhibition was 87 and 73%, respectively). The LP polyphenol-rich extracts were also safe on caco-2 intestinal cells, and no mutagenicity was detected. The UAE had lower efficiency in obtaining LP polyphenol-rich extracts. MAE equaled CE's efficiency, saving time and energy. LP shows potential as a sustainable raw material, allowing diverse extraction methods to safely develop health-promoting food and nutraceutical ingredients.

In silico study of myomere muscle proteins extracted from Indian walking catfish reveal Angiotensin Converting Enzyme (ACE) inhibitory activity – A potential bioactive peptide

Clarias magur (Hamilton, 1822), is an endemic Asian freshwater catfish known as the walking catfish is one of the most popular fish in India and Asian subcontinents due to its nutritional value and better taste. The fish has traditionally been used for medicinal purposes. The present study was undertaken to study the proteome profile through Liquid Chromatography based Mass spectroscopy (LC/MS) to elucidate the protein profile the catfish. In the present study muscle protein extract was prepared from C. magur, digested by trypsin for LC/MS analysis for peptide retrieval. Out of a total of 468 peptides retrieved from LCMS data, 23 peptides showed bioactivity for Angiotensin Converting Enzyme (ACE) inhibition using bioinformatic approaches. ACE enzyme is expressed on the surface of lung cells and acts as a receptor for SARS-CoV-2 spike protein to gain entry into host cells. ACE inhibitors can have implication in entry of virus into host cells and reduction of hypertension by effectively reducing vasoconstriction. Traditionally synthetic compounds used for ACE inhibition pose side effects. Fish derived ACE inhibitory bioactive peptides can prove to be a natural, less toxic therapeutic sources.

Multifunctional apple seed protein hydrolysates: Impact of enzymolysis on the biochemical, techno-functional and in vitro α-glucosidase, pancreatic lipase and angiotensin-converting enzyme inhibition activities

The work was designed to assess the amelioration effect of papain hydrolysis on the biochemical, techno-functional, and biological properties of apple seed protein isolate (API) after 0–90 min of hydrolysis. Hydrolysis significantly enhanced the nutritional value (protein content ˃ 90 %) while decreasing the average particle size. With increasing hydrolysis time, FTIR analysis revealed a transition from α-helix to β-turn structure, indicating the unfolding of protein structure. This structural alteration positively influenced the functional characteristics, with samples hydrolyzed for 90 min exhibiting excellent solubility, higher water and oil absorption capacity, foaming capacity, and increased emulsifying activity index. Moreover, samples hydrolyzed for 90 min displayed the highest α-glucosidase (29.62–57.43 %), pancreatic lipase inhibition (12.87–31.08 %), and ACE inhibition (25.32–62.70 %) activity. Interestingly, the inhibiting ability of protein hydrolysates against α-glucosidase and ACE was more effective than pancreatic lipase, suggesting their usefulness as a functional ingredient, particularly in type II diabetes and hypertension management.

In silico Evaluation of ACE2 Inhibition by Prunus armeniaca L. and in vivo Toxicity Study.

SARS-CoV-2 is a virus that uses ACE2 to enter the host cell. This study aimed to evaluate the in silico inhibitory activity of polyphenols from Prunus armeniaca (P. armeniaca) on angiotensin-converting enzyme 2 (ACE2). The efficacy of phytocompounds from P. armeniaca in inhibiting ACE2 was tested through molecular docking and dynamic analyses. The toxicological analysis of P. armeniaca was also evaluated. A total of twenty polyphenols were docked against the ACE2 active site, and four compounds showed interesting profiles. In vivo acute toxicity study demonstrated that the aqueous extract of Prunus armeniaca was safe. Four compounds from Prunus armeniaca seem to exert an inhibitory potential of ACE2.

Development and evaluation of anti-reflux functional-oral suspension raft composed of sodium alginate-mung bean protein complex

This study aimed to develop a sodium alginate (Na alginate) and mung bean protein (MBP) raft complex to improve gastric reflux symptoms. Na alginate and MBP complexes with different ratios (1:1, 2:1, and 3:1, respectively) were used for raft formulations through a wet Maillard reaction. Structural properties of raft strength, reflux resistance, intrinsic fluorescence emission spectroscopy, and Fourier transform infrared spectroscopy (FTIR) were investigated for rafts. The suspension 1:1 Na alginate/MBP with 0 h Maillard reaction time exhibited the lowest sedimentation volume among the suspensions. In contrast, 3:1 Na alginate/MBP with 6 h Maillard reaction time showed the highest sedimentation volume. Based on the results, the 3:1 Na alginate/MBP rafts had the best results, and the results were within acceptable limits. Functional properties, including antioxidant properties, the Helicobacter pylori inhibition assay, the pancreatic lipase inhibition assay, and angiotensin-converting enzyme (ACE) inhibition, were investigated for rafts. The Na alginate/MBP raft has similar characteristics to Gaviscon syrup and can be used for obesity, Helicobacter pylori infection, high blood pressure, and gastric reflux.

Sustained drug release behavior of captopril-incorporated chitosan/carboxymethyl cellulose biomaterials for antihypertensive therapy

Captopril (CTP) is an oral drug widely used to treat high blood pressure and congestive heart failure. In this study, CTP-incorporated biomaterials for antihypertensive therapy were synthesized from chitosan, carboxymethyl cellulose, and plasticizers. The physicochemical properties of the prepared biomaterials were characterized using FE-SEM, FT-IR analysis, and physical properties. CTP release experiments were carried out in buffer solutions at various pH values and temperatures. Results indicated that above 99.0 % of CTP was released within 180 min. Optimization of the experimental conditions for CTP release was analyzed by using response surface methodology (RSM). Results of CTP release through artificial skin indicated that CTP was continuously released above 95.0 % from the prepared biomaterials for 36.0 h. The CTP release mechanisms into a buffer and through artificial skin followed pseudo-Fickian diffusion mechanism and non-Fickian diffusion mechanisms, respectively. Moreover, angiotensin-converting enzyme (ACE) inhibition (related to cardiovascular disease) via the released CTP clearly reveals that the prepared biomaterials have a high potential as a transdermal drug delivery agent in antihypertensive therapy.

A novel heat-stable angiotensin-converting enzyme zinc-binding motif inhibitory peptide identified from corn silk

Ethnopharmacological relevanceHypertension is the most common and chronic severe health problem globally. Corn silk (CS), the silky fibers of corn (Zea mays L.), has a long history of traditional usage as a remedy for edema and hypertension. Aim of the studyThe aim of the study was to explore the underlying mechanism by which CS exerts its anti-hypertensive effects and investigate the presence of bioactive molecules in CS aqueous extract. Materials and methodsWe analyzed the effects of boiling water extract of CS on angiotensin-converting enzyme (ACE) activities, the critical enzyme involved in the regulation of blood pressure. ACE inhibitory peptides from CS extract were identified using proteomics and bioinformatics tools. The binding interfaces between these peptides and ACE were defined by hydrogen-deuterium exchange mass spectrometry (HDX-MS). Subsequently, the anti-hypertensive effects of peptides were further investigated in spontaneously hypertensive rats (SHR). ResultsOur data showed that CS extract exhibited dose-dependent inhibition of ACE activity. Liquid chromatography-tandem mass spectrometry identified a heat-stable peptide bank with 1313 distinct peptide fragments within the CS boiling water extract. Among these, CS-1 (LVPGWTKPICIGR) was selected through PeptideRanker and BIOPEP-UWM analyses. In vitro ACE inhibitory assays confirmed that CS-1 exhibited dose-dependent ACE inhibition, with IC50 values of 10.32 ± 0.41 μmol/L (using HHL as the substrate) and 13.74 ± 1.87 μmol/L (using ZFHL as the substrate). Oral administration of CS-1 led to a significant dose-dependent reduction in blood pressure, with the maximal decrease (42.33 ± 13.08 mmHg) occurring 0.5 h after ingestion. HDX-MS analysis revealed that CS-1 interacted with the zinc-binding motif of ACE, and hydrogen bond interactions were predicted between CS-1 and specific residues, including His361 in the N-domain, as well as His382, Gly386, and His387 in the C-domain of ACE. These findings suggested that the interaction of CS-1 with the residues in the zinc-binding motif of ACE led to ACE activity inhibition and a subsequent decrease in blood pressure in rats. ConclusionsA novel heat-stable ACE inhibitory peptide, which interacted with the zinc-binding motif of ACE and reduced blood pressure in SHR, was identified in the CS extract. The presence of ACE inhibitory peptides in the CS extract supports its traditional use in ethnopharmacology for hypertension.

Study of the Physiochemical and Nutraceutical Properties of Sour and Sweet Pomegranate Juice in Northern Jordan

Pomegranate juice (PJ) is the major pomegranate product that offers a simple way to consume pomegranate’s biologically active compounds, obtained from arils. In this study, we objectively investigate the physiochemical properties such as pH value, total soluble solids, color parameters, fructose and glucose contents, hydroxymethyl furfural (HMF) content, and viscosity. Also, the phytochemical content includes total phenols content, antioxidant activity, flavonoid, anthocyanin content, and phenolic quantification. In addition, the alpha-amylase and angiotensin-converting enzyme inhibitory activities among sweet and sour varieties of pomegranate juice obtained from different regions in Northern Jordan (Ajloun, Dair Abi Said, and Kufur Soum) where the significant differences at P ≤ 0.05 appeared among sweet and sour varieties in different pomegranate juice samples. The pH values for pomegranate juice range from 2.87 to 3.77, and TSS ranges from 15.36 to 16.9 Brix. The total phenol content of pomegranate juice ranged from 105.8 to 238.63 mg/g while the total flavonoid content was present in the range of 135.53–184.9 mg/g. The DPPH inhibition (%) of pomegranate juice ranged between 20.66% and 50.63%, and the anthocyanin content range was 3.66–11.02 mg/g. Ellagic acid, delphinidin, 3,4-dihydroxyphenethyl alcohol, 2-hydroxyphenethyl alcohol, catechin, epicatechin, vanillic acid, caffeic acid, P-coumaric acid, chlorogenic acid, gallic acid, ferulic acid, and syringic acid are phenolics present predominantly in pomegranate juice. Pomegranate juice exhibits high alpha-amylase and angiotensin-converting enzyme inhibition activity. All results indicate good quality and health properties for pomegranate juice.

ACE I/D genotype associates with strength in sarcopenic men but not with response to ACE inhibitor therapy in older adults with sarcopenia: Results from the LACE trial.

Angiotensin II (AII), has been suggested to promote muscle loss. Reducing AII synthesis, by inhibiting angiotensin converting enzyme (ACE) activity has been proposed as a method to inhibit muscle loss. The LACE clinical trial was designed to determine whether ACE inhibition would reduce further muscle loss in individuals with sarcopenia but suffered from low recruitment and returned a negative result. Polymorphic variation in the ACE promoter (I/D alleles) has been associated with differences in ACE activity and muscle physiology in a range of clinical conditions. This aim of this analysis was to determine whether I/D polymorphic variation is associated with muscle mass, strength, in sarcopenia or contributed to the lack of response to treatment in the LACE study. Sarcopenic individuals were recruited into a 2x2 factorial multicentre double-blind study of the effects of perindopril and/or leucine versus placebo on physical performance and muscle mass. DNA extracted from blood samples (n = 130 72 women and 58 men) was genotyped by PCR for the ACE I/D polymorphism. Genotypes were then compared with body composition measured by DXA, hand grip and quadriceps strength before and after 12 months' treatment with leucine and/or perindopril in a cross-sectional analysis of the influence of genotype on these variables. Allele frequencies for the normal UK population were extracted from 13 previous studies (I = 0.473, D = 0.527). In the LACE cohort the D allele was over-represented (I = 0.412, D = 0.588, p = 0.046). This over-representation was present in men (I = 0.353, D = 0.647, p = 0.010) but not women (I = 0.458, D = 0.532, p = 0.708). In men but not women, individuals with the I allele had greater leg strength (II/ID = 18.00 kg (14.50, 21.60) vs DD = 13.20 kg (10.50, 15.90), p = 0.028). Over the 12 months individuals with the DD genotype increased in quadriceps strength but those with the II or ID genotype did not. Perindopril did not increase muscle strength or mass in any polymorphism group relative to placebo. Our results suggest that although ACE genotype was not associated with response to ACE inhibitor therapy in the LACE trial population, sarcopenic men with the ACE DD genotype may be weaker than those with the ACE I/D or II genotype.

Bioactive potential of ripened white cheeses manufactured in different geographical regions of Turkey.

This study investigated the potential bioactive properties of white cheeses produced in different regions of Turkey, including their potential antioxidant, antihypertensive, antidiabetic, antimicrobial, and anticancer activities. The cheese samples were analyzed both before and after in vitro digestion. The study found that all cheese samples exhibited significant angiotensin-converting enzyme inhibition activity both before (45.5%-70.1% for 0.03gcheese/mL) and after in vitro digestion (25.5%-63.5% for 0.0167g cheese/mL), whereas α-amylase inhibition activity was present in all samples (in the range of 5.1%-50.0% for 3.0×10-5 gcheese/mL) but disappeared after digestion, and α-glucosidase inhibition activity was only detected after in vitro digestion (from 20.5% to 60.4% for 5.6×10-5 gcheese/mL), indicating potential antidiabetic properties. However, antimicrobial and anticancer activities were not observed in any of the samples. The results also suggest that the bioactivity potential of white cheese may vary depending on the region of production, as cheeses from the Marmara region exhibited high α-glucosidase inhibition activity after digestion. In conclusion, while white cheese is a valuable addition to the diet due to its high nutritional value and potential health benefits. This study revealed the bioactive potential of ripened white cheese and in vivo investigations of the cheese components would better show their possible benefits. PRACTICAL APPLICATION: Although the bioactivity potentials varied among the ripened white cheese samples produced in different regions of Turkey, a consistent trend was observed in terms of their presence or absence. Our research revealed that all ripened cheese samples demonstrated significant potential antioxidant and antihypertensive activities, as well as potential antidiabetic properties. Moreover, it can be interpreted that ripened white cheese has the potential to reduce the digestion of carbohydrates when consumed with carbohydrate-rich foods. Although the present results provide limited practical findings directly applicable to the industry, if the data and information obtained from this study are further explored and further studies delving into specific mechanisms of bioactive components could emerge.

Experimental investigation of sustainable Corrosion Inhibitor Albumin on low-carbon steel in 1N HCl and 1N H2SO4

Sustainable corrosion inhibitors are being developed as many of them are ecologically friendly, biodegradable, and devoid of heavy metals and other potentially dangerous compounds. Albumin, a member of the globular protein family obtained from egg white, has found its application in a variety of various applications due to its intrinsic pharmacological qualities (anti-bacterial, immunomodulating, and anti-cancer angiotensin-converting enzyme inhibition). Herein, Albumin extract containing atoms with lone pairs of electrons such as Nitrogen (N), Oxygen (O) and having an aromatic ring (unsaturation) has been investigated as an eco-friendly inhibitor for low-carbon steel. The present work studied the inhibition action of Albumin extract for low-carbon steel in 1N acidic chloride and sulfate media using gravimetric, and electrochemical methods, viz potentiodynamic polarization (PDP) and AC impedance studies (EIS). The results obtained from PDP and EIS analysis revealed that the inhibitor exhibited anodic inhibition in 1N HCl (92.72%) and mixed-type but predominantly cathodic inhibition in 1N H2SO4 (79.23%). The studied green corrosion inhibitor followed Langmuir monolayer adsorption and the formation of a protective film on a low-carbon steel surface was confirmed with AFM and FT-IR results. Thus, Albumin extract exhibited excellent corrosion resistance on low-carbon steel.

Curcumin Nanoemulsion: Unveiling Cardioprotective Effects via ACE Inhibition and Antioxidant Properties in Hypertensive Rats.

Background and Objectives: Curcumin, derived from Curcuma longa, is a well-known traditional medicinal compound recognized for its therapeutic attributes. Nevertheless, its efficacy is hampered by limited bioavailability, prompting researchers to explore the application of nanoemulsion as a potential alternative. Materials and Methods: This study delves into the antihypertensive effects of curcumin nanoemulsion (SNEC) by targeting the renin-angiotensin-aldosterone system (RAAS) and oxidative stress in deoxycorticosterone acetate (DOCA) salt-induced hypertensive rats. To gauge the cardio-protective impact of SNEC in DOCA salt-induced hypertension, molecular docking was undertaken, uncovering curcumin's high affinity and adept binding capabilities to the active site of angiotensin-converting enzyme (ACE). Additionally, the investigation employed uninephrectomized rats to assess hemodynamic parameters via an AD instrument. Serum ACE, angiotensin II, blood urea nitrogen (BUN), and creatinine levels were quantified using ELISA kits, while antioxidant parameters were evaluated through chemical assays. Result: The outcomes of the molecular docking analysis revealed robust binding of curcumin to the ACE active site. Furthermore, oral administration of SNEC significantly mitigated systolic, diastolic, and mean arterial blood pressure in contrast to the DOCA-induced hypertensive group. SNEC administration also led to a reduction in left ventricular end-diastolic pressure (LVEDP) and an elevation in the maximum rate of left ventricular pressure rise (LV (dP/dt) max). Moreover, SNEC administration distinctly lowered serum levels of ACE and angiotensin II compared to the hypertensive DOCA group. Renal markers, including serum creatinine and BUN, displayed a shift toward normalized levels with SNEC treatment. Additionally, SNEC showcased potent antioxidant characteristics by elevating reduced glutathione, catalase, and superoxide dismutase levels, while decreasing the concentration of thiobarbituric acid reactive substances. Conclusions: Collectively, these findings underscore that curcumin nanoemulsion exerts noteworthy cardio-protective effects through ACE activity inhibition and remarkable antioxidant properties.

Standardised flavonoid extract from Diospyros kaki L.f leaves alleviates high blood pressure and ventricular hypertrophy on cortisone acetate-induced hypertensive rats

The current study was designed to investigate the anti-hypertensive effects of a standardised flavonoid extract from Diospyros kaki L.f leaves (DK extract) on cortisone acetate-induced hypertensive rats. Hypertension was induced in Wistar rats by subcutaneously injecting 2.5 mg cortisone acetate daily and by maintaining the rats on a 1% sodium chloride diet for a period of 28 days. The hypertensive rats were treated daily with DK extract (50 and 100 mg/kg of body weight; p.o.) or captopril (20 mg/kg of body weight; p.o.), a reference drug, for 14 consecutive days. The blood pressure and heart rate of awake rats were measured using a non-invasive tail-cuff method. The heart weight and left ventricular wall thickness of rats were measured. In vitro angiotensin-converting enzyme (ACE) inhibition activity of the DK extract and captopril were analysed. DK extract significantly and dose-dependently reduced systolic and diastolic blood pressure in the hypertensive rats. There were no significant changes observed in heart rate. The cortisone acetate-induced hypertensive rats had increased heart weight and left ventricular wall thickness. These actions were attenuated by the treatment of DK extract (100 mg/kg) and captopril. Moreover, DK extract inhibited ACE activity in vitro with an IC50 of 4.71±0.53 μg/ml. Our findings demonstrate that DK extract exerted anti-hypertensive effects and alleviated ventricular hypertrophy in the cortisone acetate-induced hypertensive rats and these actions occurred at least in part via ACE activity inhibition.

Lactic acid fermentation of guava juice: Evaluation of nutritional and bioactive properties, enzyme (α-amylase, α-glucosidase, and angiotensin-converting enzyme) inhibition abilities, and anti-inflammatory activities.

In the present research, the impact of fermentation with two strains of Lactiplantibacillus plantarum subsp. plantarum (PTCC 1896 and PTCC 1745) on physicochemical properties, antioxidant bioactive compounds, and some health-promoting features of guava juice was investigated. Results showed a significant (p < .05) decrease in pH, total soluble solids, glucose and fructose residues, vitamin C, and total carotenoids after 32 h of fermentation. Total phenolic content, free radical scavenging abilities, and ferrous reducing power were markedly enhanced during the fermentation process. Moreover, fermented juice represented good enzyme inhibition abilities (α-amylase and α-glucosidase) and anti-inflammatory activities. The initial amount of angiotensin-converting enzyme inhibitory activity (26.5%) increased to 72.1% and 66.4% in L. plantarum subsp. plantarum 1896 and L. plantarum subsp. plantarum 1745 treatments, respectively. These findings reveal that guava juice fermentation with the studied Lactobacillus strains can be a promising strategy to augment the functional properties of the fruit-based beverage.

Bioactivity and volatile compound evaluation in sheep milk processed by ohmic heating

Ohmic heating may improve bioactive compounds and processing, ensuring food safety of beverages, liquid and pasty food, or liquid with solid pieces. Due to those traits, this study conducted a comparison between ohmic heating technology and conventional heating (CH), with a focus on assessing the impact of both methods on functional compounds (such as angiotensin-converting enzyme inhibition, α-amylase and α-glucosidase inhibition, and antioxidant activity) in both fresh and thawed raw sheep milk, which had been frozen for up to 3 mo. Different ohmic heating conditions were applied and compared to CH (3.33-8.33 V/cm vs. CH [73°C/15 s]). A total of 18 peptides with some functional activities were identified by MALDI-TOF mass spectrometry analysis. Ohmic heating samples presented the highest activities related to health, followed by CH and raw milk samples; antioxidant activity range was from 0.11% to 0.71%, antihypertensive activity ranged from 0.20% to 0.72%, and antidiabetic activity ranged from 0.21% to 0.79%. Of 51 volatile compounds detected, some were degraded by freezing, storing, and heating the sheep milk. This study showed for the first time that ohmic heating processing improved sheep milk bioactive peptides and preserved volatile compounds.

α-Glucosidase, Angiotensin-converting Enzyme, and Acetylcholinesterase Inhibitory Activities of a Marine Red Alga Galaxaura oblongata

Seaweeds have gained interest from the pharmaceutical industry due to their diverse secondary metabolites with potential applications in the prevention and treatment of lifestyle diseases. In spite of the abundance of seaweeds in the coastal area of Iligan Bay in the Philippines, there has been limited investigation into their pharmacological properties. Therefore, this study aimed to evaluate the in vitro α-glucosidase inhibition, angiotensin-converting enzyme (ACE) inhibition, and acetylcholinesterase (AChE) inhibition properties of various fractions obtained from the marine red alga Galaxaura oblongata. The methanol extract of G. oblongata was sequentially partitioned into hexane, dichloromethane, ethyl acetate, butanol, and methanol fractions. All assays were performed in vitro and microplate based. The results of α-glucosidase inhibition activity assay showed that the n-hexane fraction and dichloromethane fraction exhibited greater than 50% inhibitory activity at 200 ppm. Furthermore, ACE inhibition activity assay revealed that dichloromethane fraction, ethyl acetate fraction, and butanol fraction displayed ACE inhibition activity above 50% at 250 ppm. In addition, the hexane fraction, dichloromethane fraction, and ethyl acetate fraction demonstrated potent AChE inhibitory activity at 250 ppm. Overall, the findings show that G. oblongata has antidiabetic, anti-hypertensive, and neuroprotective potentials. This is the first report of the in vitro α-Glucosidase, ACE, and AChE inhibition activities of G. oblongata. Further investigation and purification of the highly potent fractions in each assay is highly suggested to identify and characterize the compounds responsible for the observed bioactivities, which could serve as possible leads for drug discovery efforts in the management of various lifestyle diseases.

Primary Exposure to SARS-CoV-2 via Infection or Vaccination Determines Mucosal Antibody-Dependent ACE2 Binding Inhibition.

Mucosal antibodies play a critical role in preventing SARS-CoV-2 infections or reinfections by blocking the interaction of the receptor-binding domain (RBD) with the angiotensin-converting enzyme 2 (ACE2) receptor on the cell surface. In this study, we investigated the difference between the mucosal antibody response after primary infection and vaccination. We assessed longitudinal changes in the quantity and capacity of nasal antibodies to neutralize the interaction of RBD with the ACE2 receptor using the spike protein and RBD from ancestral SARS-CoV-2 (Wuhan-Hu-1), as well as the RBD from the Delta and Omicron variants. Significantly higher mucosal IgA concentrations were detected postinfection vs postvaccination, while vaccination induced higher IgG concentrations. However, ACE2-inhibiting activity did not differ between the cohorts. Regarding whether IgA or IgG drove ACE2 inhibition, infection-induced binding inhibition was driven by both isotypes, while postvaccination binding inhibition was mainly driven by IgG. Our study provides new insights into the relationship between antibody isotypes and neutralization by using a sensitive and high-throughput ACE2 binding inhibition assay. Key differences are highlighted between vaccination and infection at the mucosal level, showing that despite differences in the response quantity, postinfection and postvaccination ACE2 binding inhibition capacity did not differ.

Natural angiotensin converting enzyme inhibitors: A safeguard against hypertension, respiratory distress syndrome, and chronic kidney diseases.

Hypertension is a serious concern as it is one of the causes of kideny failure and pulmonary fibrosis. An important therapeutic strategy for treating chronic hypertension is to inhibit the angiotensin converting enzyme (ACE). ACE inhibition reduces kidney damage, pulmonary artery pressure, and high blood pressure. Due to their high efficacy and low risk of side effects, natural renin-angiotensin system inhibitors have drawn increasing attention over the past decades. Alkaloids, amino acids, anthocyanidins, flavonoids, glucosinolates, isoflavonoids, phenolic acids, polyphenolics, and triterpenoids are among the bioactive metabolites pocessing an impressive ACE inhibitory activity. Many herbs including Rosmarinus officinalis, Hibiscus sabdariffa, Curcuma longa, Rauwolfia serpentina, Emblica officinalis, Cynara scolymus, Punica granatum, Mucuna pruriens, Capsicum annuum, and Moringa olifera were found having ACE inhibitory activities comparable to captopril and enalpril. These enticing natural ACE inhibitors deserve to be a safeguard medicine against hypertension, respiratory distress syndrome, and chronic kidney diseases. More clinical trials are required before new natural compounds and herbs can be used to treat chronic hypertension and its ramifications, such as respiratory distress syndrome and kidney failure.

Bioactive angiotensin converting enzyme inhibitory activity and antihypertensive activity derived from fish protein hydrolysate: a systematic review

In the fish processing sector, fish have been processed in large quantities, are generated and discarded into the sea or dumped into the oceans. However, by employing effective strategies, this fishery waste can be utilized and converted into fish protein hydrolysate (FPH). FPH is a rich source of amino acids and peptides that have biological properties such as angiotensin-converting enzyme (ACE) inhibition, antimicrobial, antioxidant, and anticancer activity. The FPH has been used as a functional food perspective related to improving human health, primarily by maintaining blood pressure and normal heart function as measured by antihypertensive activity. FPH can be produced by various fish species, parts, and hydrolysis methods. Several studies have been published on the acceptability of FPH in obtaining bioactive properties from various fish, each using a different method to obtain bioactive properties. FPH is commonly produced by fish species such as Atlantic Cod, Lizard Fish, Atlantic Chub Mackerel, Atlantic Horse Mackerel, and Kawakawa (Mackerel Tuna). Furthermore, we summarized the various methodologies used by various researchers based on raw material data collection, method of production, ACE-inhibitory assay, ACE-inhibitory activity, degree of hydrolysis, molecular weight, purification method, and ACE-I peptide structure in this review.