Blood pressure reduction and clinical outcomes with angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers: protocol for a systematic review and meta-regression analysis

Dual role for angiotensin-converting enzyme 2 in Severe Acute Respiratory Syndrome Coronavirus 2 infection and cardiac fat

Angiotensin-converting enzyme 2 (ACE2) has been an increasingly prevalent target for investigation since its discovery 20 years ago. The finding that it serves a counterregulatory function within the traditional renin-angiotensin system, implicating it in cardiometabolic health, has increased its clinical relevance. Focus on ACE2's role in cardiometabolic health has largely centered on its apparent functions in the context of obesity. Interest in ACE2 has become even greater with the discovery that it serves as the cell receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), opening up numerous mechanisms for deleterious effects of infection. The proliferation of ACE2 within the literature coupled with its dual role in SARS-CoV-2 infection and obesity necessitates review of the current understanding of ACE2's physiological, pathophysiological, and potential therapeutic functions. This review highlights the roles of ACE2 in cardiac dysfunction and obesity, with focus on epicardial adipose tissue, to reconcile the data in the context of SARS-CoV-2 infection.

Berberine in the treatment of metabolism-related chronic diseases: A drug cloud (dCloud) effect to target multifactorial disorders

Berberine (BBR) is a multi-target drug (MTD) that has proven effective in the treatment of metabolism-related chronic diseases (CDs). However, the mode of action (MOA) of BBR remains to be clarified. At a cellular level, the inhibitory effect of BBR on mitochondrial enzymes is probably responsible for many of its biological activities, including the activation of low-density lipoprotein receptor (LDLR), AMP-activated protein kinase (AMPK) and insulin receptor (InsR); these biological activities contribute to ameliorate peripheral blood metabolic profiles, e.g. by reducing plasma lipids and glucose levels, thus improving signs and symptoms of metabolic disorders. In this perspective, BBR acts as a targeted therapy. However, it also exerts pleiotropic systemic activities on some root causes of CDs that include antioxidant / anti-inflammatory effects and modifications of gut microbiota composition and metabolism, which may also contribute to its disease-modifying effects. After reviewing the different MOA of BBR, here we propose that BBR acts through a drug-cloud (dCloud) mechanism, as different to a drug-target effect. The dCloud here is defined as a group of terminal molecular events induced by the drug (or/and related metabolites), as well as the network connections among them. In this scenario, the therapeutic efficacy of BBR is the result of its dCloud effect acting on symptoms/signs as well as on root causes of the diseases. The dCloud concept is applicable to other established MTDs, such as aspirin, metformin, statins as well as to nutrient starvation, thus providing a novel instrument for the design of effective therapies against multifactorial metabolism-related CDs.

In Vitro Study of Multi-Therapeutic Properties of Thymus bovei Benth. Essential Oil and Its Main Component for Promoting Their Use in Clinical Practice

Thymus bovei Benth. (TB) is an important plant in the traditional medicine of the Mediterranean region. This study investigates the health-promoting properties of TB essential oil (TB-EO) for its possible use in clinical practice with regards to its cytotoxic, anti-herpes simplex virus type 2 (HSV-2), and antihypertensive (through inhibition of human angiotensin-converting enzyme; ACE) properties. The phytochemical profile of EO (99.9%) was analyzed by Gas Chromatography with Flame-Ionization Detection (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS). In this study, all biological methods were performed at the level of in vitro studies. The results showed that TB-EO exerted remarked cytotoxic properties against human cervical carcinoma cells, colon cancer cells, and lung adenocarcinoma cells with the half-maximal inhibitory concentration (IC₅₀) values of 7.22, 9.30, and 8.62 µg/mL, respectively, in comparison with that of standard anticancer drug cisplatin with IC₅₀ values of 4.24, 5.21, and 5.43 µg/mL, respectively. Fascinatingly, TB-EO showed very weak cytotoxicity on the healthy human fetal lung fibroblast cells with an IC₅₀ value of 118.34 µg/mL compared with that of cisplatin (IC₅₀ = 10.08 µg/mL). TB-EO, its main component geraniol, TB-EO combined with acyclovir (ACV) along with standard ACV, have displayed pronounced inhibitory properties against the replication of HSV-2 with the half-maximal effective concentration (EC₅₀) values of 2.13, 1.92, 0.81 and 1.94 µg/mL, respectively, with corresponding selectivity indices (SI) 98.59, 109.38, 259.26 and 108.25, respectively. TB-EO and geraniol at a concentration of 15 µg/mL showed prominent inhibitory activities against ACE with % of inhibition 95.4% and 92.2%, respectively, compared with that of standard inhibitor captopril (99.8%; 15 µg/mL). Molecular docking studies were performed to unveil the mechanism of action of geraniol as well as structural parameters necessary for anti-HSV-2 activity (through the inhibition of HSV-2 protease) and ACE inhibition. This is the first report on the chemical composition of Egyptian TB-EO along with the above-mentioned biological activities. Our results may be considered as novel findings in the course of a search for new and active anticancer, anti-HSV-2 and antihypertensive agents, and expand the medicinal value of this plant and its phytochemicals in clinical practice.