A comparative study of two clerodane diterpenes from Baccharis trimera (Less.) DC. on the influx and mobilization of intracellular calcium in rat cardiomyocytes

Effects of plant extracts and derivatives on cardiac K+, Nav, and Cav channels: a review

Natural products (NPs) are endless sources of compounds for fighting against several pathologies. Many dysfunctions, including cardiovascular disorders, such as cardiac arrhythmias have their modes of action regulation of the concentration of electrolytes inside and outside the cell targeting ion channels. Here, we highlight plant extracts and secondary metabolites' effects on the treatment of related cardiac pathologies on hERG, Nav, and Cav of cardiomyocytes. The natural product's pharmacology of expressed receptors like alpha-adrenergic receptors causes an influx of Ca2+ ions through receptor-operated Ca2+ ion channels. We also examine the NPs associated with cardiac contractions such as myocardial contractility by reducing the L-type calcium current and decreasing the intracellular calcium transient, inhibiting the K+ induced contractions, decreasing amplitude of myocyte shortening and showed negative ionotropic and chronotropic effects due to decreasing cytosolic Ca2+. We examine whether the NPs block potassium channels, particular the hERG channel and regulatory effects on Nav1.7.

Vasorelaxant effects of ellagitannins isolated from Cuphea carthagenensis

Cuphea carthagenensis (Jacq.) J. F. Macbr. is a popular plant in Brazilian folk medicine owing to its hypotensive and central nervous system depressant effects. This study aimed to validate the hypotensive effect of the plant's aqueous extract (AE) in rats and examine the vascular actions of three hydrolyzable tannins, oenothein B, woodfordin C, and eucalbanin B, isolated from AE. Systolic blood pressure in unanesthetized rats was determined using the non-invasive tail-cuff method. Oral treatment of normotensive rats with 0.5 and 1.0 g/kg/day AE induced a dose-related hypotensive effect after 1 week. In rat aortic rings pre-contracted with noradrenaline, all ellagitannins (20 - 180 µM) induced a concentration-related vasorelaxation. This effect was blocked by either removing the endothelium or pre-incubating with NG-nitro-l-arginine methyl ester (10 µM), an inhibitor of nitric oxide (NO) synthase. In KCl-depolarized rat portal vein preparations, the investigated compounds did not affect significantly the maximal contractile responses and pD2 values of the concentration-response curves to CaCl2. Our results demonstrated the hypotensive effect of C. carthagenensis AE in unanesthetized rats. All isolated ellagitannins induced vasorelaxation in vitro via activating NO synthesis/NO release from endothelial cells, without altering the Ca2+ influx in vascular smooth muscle preparations. Considering the low oral bioavailability of ellagitannins, the determined in vitro actions of these compounds are unlikely to account for the hypotensive effect of AE in vivo. It remains to be determined the role of the bioactive ellagitannin-derived metabolites in the hypotensive effect observed after oral treatment of unanesthetized rats with the plant extract.

Pro-Apoptotic and Anti-Cancer Activity of the Vernonanthura Nudiflora Hydroethanolic Extract

The mitochondrial voltage-dependent anion channel 1 (VDAC1) protein is involved in several essential cancer hallmarks, including energy and metabolism reprogramming and apoptotic cell death evasion. In this study, we demonstrated the ability of hydroethanolic extracts from three different plants, Vernonanthura nudiflora (Vern), Baccharis trimera (Bac), and Plantago major (Pla), to induce cell death. We focused on the most active Vern extract. We demonstrated that it activates multiple pathways that lead to impaired cell energy and metabolism homeostasis, elevated ROS production, increased intracellular Ca²⁺, and mitochondria-mediated apoptosis. The massive cell death generated by this plant extract's active compounds involves the induction of VDAC1 overexpression and oligomerization and, thereby, apoptosis. Gas chromatography of the hydroethanolic plant extract identified dozens of compounds, including phytol and ethyl linoleate, with the former producing similar effects as the Vern hydroethanolic extract but at 10-fold higher concentrations than those found in the extract. In a xenograft glioblastoma mouse model, both the Vern extract and phytol strongly inhibited tumor growth and cell proliferation and induced massive tumor cell death, including of cancer stem cells, inhibiting angiogenesis and modulating the tumor microenvironment. Taken together, the multiple effects of Vern extract make it a promising potential cancer therapeutic.

Baccharis trimera Infusion Reduces Macrophages Activation and High-Fat Diet-Induced Metabolic Disorders in Mice

The aim of this study is to evaluate the efficacy of Baccharis trimera infusion on high-fat diet-induced metabolic disorders in mice and macrophages activation. This study evaluated obesity, insulin resistance, dyslipidemia and hepatic steatosis induced by a high-fat diet in Swiss mice. Cellular parameters in macrophages, such as cell viability (MTT), the production and release of nitric oxide (NO) and hydrogen peroxide (H₂O₂), cell spreading, cell adhesion and phagocytosis were determined. Our results showed that treatment with B. trimera prevented the mentioned conditions, except for the production of hydrogen peroxide. B. trimera prevented the development of obesity and associated comorbidities, as well as activation of macrophages. In conclusion, B. trimera is able to prevent obesity and metabolic disorders and macrophages activation, minimizing inflammation and validating the popular use of this plant tea.

Baccharis trimera (Less.) DC: An Innovative Cardioprotective Herbal Medicine Against Multiple Risk Factors for Cardiovascular Disease

Cardiovascular disease (CVD) is the leading cause of death worldwide and among its modifiable risk factors are dyslipidemia, diabetes, and smoking. Experimental models evaluated this risk factors singly, however, there is a lack of models that agglomerate these risk factors, resembling real patients and elucidating the pathophysiology of CVD. Moreover, few studies have investigated the cardioprotective effects of Baccharis trimera, a species with lipid-lowering effects. In this study, ethanol-soluble fraction of B. trimera was characterized by liquid chromatography-mass spectrometry. Diabetes was induced by streptozotocin in Wistar rats that also received 0.5% cholesterol-enriched chow and were exposed to the smoke of nine cigarettes, 5 days/week, for 4 weeks. During the last 2 weeks, the animals were treated with vehicle (C^-), B. trimera, or simvastatin plus insulin. At the end, cholesterol, triglyceride, urea, and creatinine levels; blood pressure (BP); heart rate (HR); abdominal aortic morphometry; vascular reactivity; renal and cardiac oxidative status; and histopathological changes were evaluated. The agglomerate of risk factors promoted alterations contrary to those described in the literature for the isolated risk factors. The C^- group exhibited oxidative stress, increase in biochemical parameters, and thickening of the wall of the abdominal aorta. HR, systolic, diastolic, and mean BP decreased, and vascular reactivity was altered. Cardiac and renal histopathological changes were observed. Treatment with B. trimera reversed these changes and this effect may be partially attributable to lipid-lowering action and to the inhibition of free radical generation. B. trimera has cardioprotective effects in this model, with no toxicity.

Therapeutic Potential of Essential Oils Focusing on Diterpenes

Among all plant derivates, essential oils (EOs) have gained the attention of many scientists. Diterpenes, a family of components present in some EO, are becoming a milestone in the EOs world. The goal of this review is to describe a scenario of diterpenes taking into health-consumption deportment. Previous studies revealed that diterpenes have antioxidant, antimicrobial, antiviral, antiprotozoal, cytotoxic, anticancer, antigenotoxic, antimutagenic, chemopreventive, antiinflammatory, antinociceptive, immunostimulatory, organoprotective, antidiabetic, lipid-lowering, antiallergic, antiplatelet, antithrombotic, and antitoxin activities. In conclusion, diterpenes may be an immense featuring concern in pharmaceutical consumption from a drug discovery point of view. Copyright © 2016 John Wiley & Sons, Ltd.