Angiotensin-1-converting enzyme inhibition, antioxidant activity, and modulation of cerebral Na+/K+ ATPase by free phenolics of African locust bean (Parkia biglobosa)

Contemporary Insights into the Biological Mechanisms of Parkia biglobosa

For a long time, traditional medicine has relied on the use of medicinal plants and herbal products which have served as the basis for numerous pharmaceuticals. Parkia biglobosa (Jacq) R.Br.ex. G. Don., commonly called the African locust bean tree, is a perennial deciduous plant native to West Africa where it is highly esteemed for its nutritional and traditional medicinal benefits. Parkia biglobosa's ethnomedicinal uses include microbial infections such as diarrhea and chronic diseases like hypertension and type 2 diabetes mellitus. This article presents the current understanding of the molecular mechanisms underlying Parkia biglobosa's biological effects. An electronic database search was conducted using P. biglobosa and its synonyms as keywords in Scientific Electronic Library Online, ISI Web of Knowledge, PubMed, Scopus, Science Direct, and Google Scholar. Consistently, scientific research has confirmed the medicinal effects of the plant's extracts and active phytochemicals, including antimicrobial, analgesic, antidiabetic, antihypertensive, hypolipidemic, and neuroprotective properties, among others. It highlights the contributions of identified innate phytochemicals and existing limitations to therapeutic applications, as well as the need for and prospects for further research. Advancing our understanding of the medicinal plant's biological mechanisms and the contributions of the active phytochemicals would allow for more effective exploration of its vast pharmacological potential and facilitate clinical applications.

Cereals as a Source of Bioactive Compounds with Anti-Hypertensive Activity and Their Intake in Times of COVID-19

Cereals have phytochemical compounds that can diminish the incidence of chronic diseases such as hypertension. The angiotensin-converting enzyme 2 (ACE2) participates in the modulation of blood pressure and is the principal receptor of the virus SARS-CoV-2. The inhibitors of the angiotensin-converting enzyme (ACE) and the block receptors of angiotensin II regulate the expression of ACE2; thus, they could be useful in the treatment of patients infected with SARS-CoV-2. The inferior peptides from 1 to 3 kDa and the hydrophobic amino acids are the best candidates to inhibit ACE, and these compounds are present in rice, corn, wheat, oats, sorghum, and barley. In addition, the vitamins C and E, phenolic acids, and flavonoids present in cereals show a reduction in the oxidative stress involved in the pathogenesis of hypertension. The influence of ACE on hypertension and COVID-19 has turned into a primary point of control and treatment from the nutritional perspective. The objective of this work was to describe the inhibitory effect of the angiotensin-converting enzyme that the bioactive compounds present in cereals possess in order to lower blood pressure and how their consumption could be associated with reducing the virulence of COVID-19.

[In vitro antioxidant and anti-inflammatory activity of chaya extracts (Cnidoscolus aconitifolius (Mill.) I.M. Johnst)]

Introduction

Introduction: noncommunicable diseases (NCDs) are the main cause of death worldwide. Secondary metabolites from plant sources such as Cnidoscolus aconitifolius may be used as adjuvants in the prevention of diseases related to oxidative stress and inflammation such as NCDs. Objective: the in vitro antioxidant and anti-inflammatory activities associated with biologically active compounds in C. aconitifolius extracts were evaluated. Method: the contents of phenols, flavonoids, flavonones and hydroflavonoles were determined. The potential antioxidant activity was determined with 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays, and angiotensin-converting enzyme (ACE) activity. For anti-inflammatory activity quantitative PCR and enzyme-linked immunosorbent assay (ELISA) tests were used in macrophages derived from THP-1 monocytes and stimulated with LPS. Results: the aqueous extract recorded the highest phenolic content (70.61  0.07 g/100 g of extract), and the ethanolic extract registered the highest content in flavonoids (47.76  4.84 g/100 g of extract), flavonones and dihydroflavonoles (70.10  7.29 g/100 g of extract). The acetone extract obtained the highest DPPH inhibition (49.85 ± 5.30%), while the ethanolic extract showed the highest ABTS inhibition (41.01 ± 3.81%). The etanolic and aqueous extracts had the highest ACE inhibition. The ethanolic extract had the highest anti-inflammatory activity, decreasing gene expression for TNF- by 39.78% and for IL-6 by 97.81%, and their production by 46% and 48.38%, respectively, in macrophages stimulated with LPS. Conclusion: these extracts demonstrated in vitro their antioxidant and anti-inflammatory potential due to their content of bioactive compounds.

Is the cardioprotective effect of the ACE2 activator diminazene aceturate more potent than the ACE inhibitor enalapril on acute myocardial infarction in rats?

Myocardial infarction is a major cause of cardiac dysfunction. All components of the cardiac renin-angiotensin system (RAS) are upregulated in myocardial infarction. Angiotensin-converting enzyme (ACE) and ACE2 are key enzymes involved in synthesis of components of RAS and provide a counter-regulatory mechanism within RAS. We compared the cardioprotective effect of the ACE2 activator diminazene aceturate (DIZE) versus the ACE inhibitor enalapril on post acute myocardial infarction (AMI) ventricular dysfunction in rats. Adult male rats received subcutaneous injections of either saline (control) or isoproterenol (85 mg/kg) to induce AMI. Rats with AMI confirmed biochemically and by ECG, were either left untreated (AMI) or administered DIZE (AMI + DIZE) or enalapril (AMI + enalapril) daily for 4 weeks. DIZE caused a significant activation of cardiac ACE2 compared with enalapril. DIZE caused a significantly greater enhancement of cardiac hemodynamics. DIZE also caused greater reductions in heart-type fatty acid binding protein (H-FABP), β-myosin heavy chain (β-MYH), and in heart mass to total body mass ratio. These results indicated that activation of cardiac ACE2 by DIZE enhanced the protective axis of RAS and improved myocardial function following AMI, whereas enalapril was not sufficient to restore all cardiac parameters back to normal.