Antihypertensive Potential of Plant Foods: Research Progress and Prospect of Plant-Derived Angiotensin-Converting Enzyme Inhibition Compounds

Discovering the natural source-derived antihypertensive compounds aspiring current therapeutic targets by computer-based drug design

Hypertension, a primary global health concern, heightens the risk of heart, brain, and kidney diseases and contributes to premature mortality. The present paper thoroughly explores the potential therapeutic use of natural compounds, drawing on Avicenna's ancient medical philosophy to highlight the role of bodily humor imbalances and lifestyle factors in hypertension. A key aspect of our study is using a computer-aided drug design (CADD) approach, which we employ to identify novel antihypertensive bio-compounds, focusing on current therapeutic targets, including angiotensin I-converting enzyme, angiotensin II receptor, and calcium channel. Comprehensive molecular docking and dynamic simulations were employed to evaluate the binding interactions and affinities of these compounds with key hypertension-related proteins. Using Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA) for binding free energy calculations and ADMET analysis to enhance the precision of our findings, we identified standout candidates from the AVICENNA database, including FDB014401, FDB014715, and FDB014560. These compounds exhibited outstanding docking scores, ranging from -9.60 to -11.60 kcal/mol across three targets, highlighting their potential to act as potent inhibitors of the intended proteins. Molecular dynamics simulations reveal that these bio-compounds maintain stable interactions with target proteins over 100 ns, with no significant conformational alterations, underscoring their promise as viable antihypertensive agents. Due to our study's thoroughness, these findings provide a solid foundation for forthcoming pre-clinic and empiric studies, and the successful use of CADD in our research instills confidence in its potential to discover novel, naturally derived antihypertensive therapies.

Heterologous expression of a recombinant ACE inhibitory peptide LYPVK and its potential antihypertensive action mechanism

Enzymatic hydrolysis approach is commonly employed for preparation of active peptides, while the limited purity and yield of produced peptides hinder further development of action mechanisms. This study presents the biotechnological approach for the efficient production of recombinant angiotensin converting enzyme (ACE) inhibitory peptide LYPVK and investigates its potential antihypertensive action mechanism. DNA encoding sequence of recombinant peptide was designed to form in tandem, which was expressed in Escherichia coli BL21 (DE3). The expressed tandem repeat protein with molecular weight of 13.4 kDa was verified by high performance liquid chromatography (HPLC) and amino acid composition. Subsequently, LYPVK was generated following His-tag removal and trypsin-mediated cleavage of the purified protein, which was performed HPLC and liquid chromatography-mass spectrometry (LC-MS) analysis. LYPVK exhibited an IC50 value of 10.6 ± 0.86 μg/mL, demonstrating a non-competitive mode of action and resistance to gastrointestinal enzyme hydrolysis and heat conditions. Molecular docking results showed that LYPVK interacted with ACE through conventional hydrogen bonds and hydrophobic interactions. Except for ACE, ALB, SRC, PPARG, and MMP9 are identified as potential key targets for its antihypertensive activity by network pharmacological analysis. This study provides a promising biotechnological approach for the preparation of active peptides with high purity and yield.

The Influence of Sodium Humate on the Biosynthesis and Contents of Flavonoid Constituents in Lemons

Sodium humate (SH) is the sodium salt of humic acid. Our previous research has demonstrated that SH has the ability to enhance the levels of total flavonoids in various parts of lemons, including the leaves, peels, pulps, and seeds, thereby improving the quality of lemons. In the current study, the regulation effect of SH on the biosynthesis and content of lemon flavonoid compounds was examined using transcriptome sequencing technology and flavonoid metabolomic analysis. Following SH treatment, the transcriptome sequencing analysis revealed 320 differentially expressed genes (DEGs) between samples treated with SH and control (CK) samples, some of which were associated with the phenylalanine pathway by KEGG annotation analysis. The levels of seven flavonoid compounds identified in lemon peels were observed to increase, and eriocitrin and isoorientin were identified as differential metabolites (DMs, VIP > 1) using OPLS-DA analysis. The integrated analysis of transcriptomics and flavonoid metabolomics indicates that SH treatment induces alterations in gene expression and metabolite levels related to flavonoid synthesis. Specifically, SH influences flavonoid biosynthesis by modulating the activity of key enzymes in the phenylalanine pathway, including HCT (O-hydroxycinnamoyltransferase) and F5H (ferulate-5-hydroxylase).

Comparative Study on Morphological Features and Chemical Components of Wild and Cultivated Angelica sinensis Based on Bionic Technologies and Chemometrics

As a traditional Chinese medicine, Angelica sinensis is primarily sourced from cultivated plants due to the significant decline in wild resources. This shift raises concerns about potential differences in efficacy resulting from variations in morphological features and chemical composition between wild (WA) and cultivated (CA) A. sinensis. In this study, a suite of advanced analytical techniques including electronic nose, electronic tongue, and electronic eye, alongside headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry and high-performance liquid chromatography, was applied to compare the morphological features and chemical components of WA and CA. Furthermore, principal component analysis and partial least-squares discriminant were employed for data analysis. The morphological features and chemical components of WA and CA were compared and analyzed. The results showed that three bionic technologies can distinguish WA from CA well and that fusion signals can distinguish better. There were differences between WA and CA in odor, taste, color, and content of the indicator components. There were correlations between the morphological features and the content of indicator components.

ACE inhibitory peptides from enzymatic hydrolysate of fermented black sesame seed: Random forest-based optimization, screening, and molecular docking analysis

In this study, black sesame seeds were fermented by Lactobacillus Plantarum NCU116 and then hydrolyzed using acid protease to improve Angiotensin-I-converting enzyme (ACE) inhibitory activity. The random forest-particle swarm optimization (RF-PSO) model was applied to predict the ACE inhibitory activity during the hydrolysis process based on the experimental data. After separating by adsorption chromatography, gel filtration chromatography, and reversed phased-high performance liquid chromatography and then screening in silico method, eight peptides were identified from fermented black sesame seed hydrolysates as ITAPHW, SLPNYHPSPR, QYLPR, IRPNGL, YHNAPIL, LSYPR, GFAGDDAPRA, and LDPNPRSF with IC50 values of 51.69 μM, 146.67 μM, 655.02 μM, 752.60 μM, 1.02 mM, 2.01 mM, 1.97 mM, and 3.43 mM, respectively. ITAPHW and SLPNYHPSPR exhibited high antioxidant activity and inhibited the ACE activity in a non-competitive pattern. Molecular docking revealed that the strong ACE inhibition of ITAPHW and SLPNYHPSPR is probably attributed to the interaction with Zn2+ of ACE.

Characterization of fermented pomegranate juice: ACE inhibitory activity under in vitro digestion, antioxidant capacity, phenolics composition, chemical properties and sensory evaluation

Consuming pomegranate juice (PJ) is beneficial for hypertensive regulation because of the phenolic compounds in PJ and their inhibitory activity on angiotensin-I-converting enzyme (ACE). To better utilize bioactive function of food, microorganism fermentation has been adopted to alter phenolic metabolism. This study confirms that even under in vitro digestion, fermented PJ (FPJ) maintains higher ACE inhibitory activity than that of PJ. The main phenolic compounds in PJ were compared either under fermentation or in vitro digestion. This study finds that fermentation promotes antioxidant capacity of PJ. The chemical properties of FPJ are evaluated and the corresponding relationship with bioactivities is analyzed. A sensory evaluation comparison is conducted between FPJ and PJ, furnishing interesting information for consumers. This study highlights the relationship between ACE inhibitory activity of PJ and phenolic composition under fermentation and in vitro digestion, providing novel insights for diet regulation of phenolic-rich FPJ in ACE inhibition therapy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-023-01388-w.

A novel angiotensin-converting enzyme (ACE) inhibitory peptide from tilapia skin: Preparation, identification and its potential antihypertensive mechanism

To obtain food-derived peptides with high ACE inhibitory activity, tilapia skin was pretreated with steam explosion prior to enzymatic hydrolysis. The results showed that steam explosion pretreatment improved the hydrolysis efficiency and ACE inhibitory activity of fish skin hydrolysates. A novel ACE inhibitory peptide VGLFPSRSF (1009.17 Da) was obtained from steam-exploded fish skin hydrolysates. VGLFPSRSF had an IC50 value of 61.43 μM for ACE inhibitory activity, showing a non-competitive binding mode and gastrointestinal enzyme hydrolysis resistance. Molecular docking results showed that VGLFPSRSF interacted with ACE receptor protein through hydrogen bonding and hydrophobic interactions. Based on the results of network pharmacological analysis and molecular docking, VGLFPSRSF might regulate blood pressure through interaction with hypertensive targets such as AKT1, ACE, CD4, REN, and MMP9. Steam-exploded tilapia skin peptides had potential antihypertension activity and might be promising to achieve high-value utilization of fish skin by-products.

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.

Oenococcus oeni allows the increase of antihypertensive and antioxidant activities in apple cider

This study aimed to investigate the impact of the malolactic fermentation (MLF) carried out by Oenococcus oeni on antihypertensive and antioxidant activities in cider. The MLF was induced using three strains of O. oeni. The modification in phenolic compounds (PCs) and nitrogen organic compounds, antioxidant, and antihypertensive activities were determined after MLF. Among the 17 PCs analyzed caffeic acid was the most abundant compound and phloretin, (-)-epicatechin, and myricetin were detected only in malolactic ciders, however, (-)-epigallocatechin was not detected after MLF. The evaluation of nitrogen organic compounds revealed a drop in total protein concentration (from 17.58 to 14.00 mg N/L) concomitantly with a significant release of peptide nitrogen (from 0.31 to a maximum value of 0.80 mg N/L) after MLF. In addition, an extracellular proteolytic activity was evidenced in all MLF supernatants. The FRAP activity increased reaching a maximum of 120.9 μmol FeSO₄/mL and the ABTS radical-scavenging activity increased until 6.8 mmol ascorbic acid/L. Moreover, the angiotensin I-converting enzyme inhibitory activity reached a maximum value of 39.8%. The MLF conducted by O. oeni in ciders enables the increase of interesting biological activities and this finding could constitute a valuable tool to add value to final product.

Evaluation of tea (Camellia sinensis L.) phytochemicals as multi-disease modulators, a multidimensional in silico strategy with the combinations of network pharmacology, pharmacophore analysis, statistics and molecular docking

Tea (Camellia sinensis L.) is considered as to be one of the most consumed beverages globally and a reservoir of phytochemicals with immense health benefits. Despite numerous advantages, tea compounds lack a robust multi-disease target study. In this work, we presented a unique in silico approach consisting of molecular docking, multivariate statistics, pharmacophore analysis, and network pharmacology approaches. Eight tea phytochemicals were identified through literature mining, namely gallic acid, catechin, epigallocatechin gallate, epicatechin, epicatechin gallate (ECG), quercetin, kaempferol, and ellagic acid, based on their richness in tea leaves. Further, exploration of databases revealed 30 target proteins related to the pharmacological properties of tea compounds and multiple associated diseases. Molecular docking experiment with eight tea compounds and all 30 proteins revealed that except gallic acid all other seven phytochemicals had potential inhibitory activities against these targets. The docking experiment was validated by comparing the binding affinities (Kcal mol^-1) of the compounds with known drug molecules for the respective proteins. Further, with the aid of the application of statistical tools (principal component analysis and clustering), we identified two major clusters of phytochemicals based on their chemical properties and docking scores (Kcal mol^-1). Pharmacophore analysis of these clusters revealed the functional descriptors of phytochemicals, related to the ligand-protein docking interactions. Tripartite network was constructed based on the docking scores, and it consisted of seven tea phytochemicals (gallic acid was excluded) targeting five proteins and ten associated diseases. Epicatechin gallate (ECG)-hepatocyte growth factor receptor (PDB id 1FYR) complex was found to be highest in docking performance (10 kcal mol^-1). Finally, molecular dynamic simulation showed that ECG-1FYR could make a stable complex in the near-native physiological condition.

Purification and Identification of a Novel Angiotensin Converting Enzyme Inhibitory Peptide from the Enzymatic Hydrolysate of Lepidotrigla microptera

In this study, Lepidotrigla microptera were hydrolyzed with four different proteolytic enzymes (Papain, neutrase, flavourzyme, and alcalase), and their distribution of molecular weights and ACE-inhibitory activity were tested. The alcalase hydrolysates showed the maximum ACE-inhibitory activity. A novel ACE-inhibitory peptide was isolated and purified from Lepidotrigla microptera protein hydrolysate (LMPH) using ultrafiltration, gel filtration chromatography, and preparative high performance liquid chromatography (prep-HPLC). The amino acid sequence of the purified peptide was identified as Phe-Leu-Thr-Ala-Gly-Leu-Leu-Asp (DLTAGLLE), and the IC50 value was 0.13 mg/mL. The ACE-inhibitory activity of DLTAGLLE was stable across a range of temperatures (<100 °C) and pH values (3.0−11.0) and retained after gastrointestinal digestion. DLTAGLLE was further identified as a noncompetitive inhibitor by Lineweaver−Burk plot. The molecular docking simulation showed that DLTAGLLE showed a high binding affinity with ACE sites by seven short hydrogen bonds. As the first reported antihypertensive peptide extracted from alcalase hydrolysate of Lepidotrigla microptera, DLTAGLLE has the potential to develop functional food or novel ACE-inhibitor drugs.

One-Step Preparative Separation of Fucoxanthin from Three Edible Brown Algae by Elution-Extrusion Countercurrent Chromatography

A method for batch preparation of fucoxanthin from brown algae was established, which possessed the advantages of high yield and high purity. The ultrasonic-assisted extraction method was used to obtain a crude extract from Sargassum fusiforme as the separation sample. Then the crude extract was separated by elution-extrusion countercurrent chromatography. The optimum preparation conditions of fucoxanthin were determined as follows: n-hexane-ethanol-water (20:9:11, v:v:v) as a two-phase solvent system, the mobile phase flow rate was 5 mL min-1, the revolution speed was 800 r min-1, the loading capacity was 60 mg 10 mL-1 and the temperature was 25 °C. By this method, 12.8 mg fucoxanthin with a purity of 94.72% was obtained from the crude extract of Sargassum fusiforme. In addition, when the loading capacity was 50 mg 10 mL-1, the purity of fucoxanthin reached 96.01%. Two types of by-products, chlorophyll and pheophytin, could also be obtained during the process of separation. This optimal method was further applied to separate fucoxanthin from Laminaria japonica and Undaria pinnatifida, and 6.0 mg and 9.7 mg fucoxanthin with a purity of 96.24% and 92.62% were acquired, respectively. Therefore, it was demonstrated that the preparation method of fucoxanthin established in this study had an applicability to brown algae, which improved the utilization value of raw materials.