Exploring antioxidant and α-glucosidase inhibition in Eugenia L. extracts: a comprehensive phytochemical study

This study analysed extracts obtained from the leaves of Eugenia uniflora, E. involucrata, and E. myrcianthes to determine their chemical composition, antioxidative properties, and α-glucosidase inhibitory capacity. By using liquid chromatography with a diode array detector, we identified chlorogenic acids, flavonoids, tannins, proanthocyanidins, saponins, and triterpenes in the extracts. The antioxidant activities of the extracts were found to be directly related to their total phenolic, flavonoid content and enzyme inhibition. The E. uniflora aqueous extract showed significant inhibition of α-glucosidase (IC50 0.98 µg mL-1), indicating its potential as a non-competitive inhibitor for managing Diabetes Mellitus. This study contributes to the existing knowledge on the chemical and biological aspects of Eugenia genus.

Cytotoxicity, anti-inflammatory effect, and acute oral toxicity of a novel Attalea phalerata kernel oil-loaded nanocapsules

The kernel oil of the Attalea phalerata Mart. Ex Spreng (Acurí) is traditionally used in several Latin American countries to treat respiratory problems, inflammation, and fever. However, it cannot be found on the literature any attend to use this oil in pharmaceutical formulation. In this paper, it was developed Acurí oil-loaded nanocapsules, and it was evaluated the cytotoxicity against cancer cells, the antinflammatory activity and the oral acute toxicity in rats. Acurí oil contains lauric acid as the predominant saturated fatty acid (433.26 mg/g) and oleic acid as the main unsaturated fatty acid (180.06 mg/g). The Acurí oil-loaded nanocapsules showed a size of 237 nm, a polydispersity index of 0.260, and a high ζ-potential of -78.75 mV. It was obtained an encapsulation efficiency of 88.77%, and the nanocapsules remain stable on the shelf for 180 days. The nanocapsules showed a rapid release profile (98.25% in 40 minutes). Nanocapsules at a dose of 10 mg/kg exhibit an anti-inflammatory effect similar to indomethacin at the same dose. The nanocapsules showed excellent antiproliferative effect and selectivity index against prostate tumor cells (IC50 2.09 µg/mL, SI=119.61) and kidney tumor cells (IC50 3.03 µg/mL, SI=82.50). Both Acurí oil and Acurí oil-loaded nanocapsules are nontoxic at a dose of 2000 mg/kg. Additionally, they reduce serum triglyceride and total cholesterol levels in rat and could find application in nutraceutical formulations. The Acurí oil-loaded nanocapsules emerge as a promising candidate for new antitumor therapies.

Cardioprotective Effects of Aloysia polystachya Essential Oil on a Rat Model with Multiple Cardiovascular Risk Factors

Traditional medicine is a frequently utilized method to treat cardiovascular disease and its primary risk factors, including hypertension and dyslipidemia. Aloysia polystachya is a species that is commonly employed to treat various pathological conditions, and it has already been identified as having some cardioprotective effects. This study aimed to investigate the protective effects of the essential oil extracted from the leaves of A. polystachya in a rat model that simulates multiple cardiovascular risk factors. We evaluate the acute toxicity, as well as the cardioprotective effects, by giving different doses of A. polystachya essential oil (1.47 mg/kg, 4.40 mg/kg, and 13.20 mg/kg) over a period of 42 days. The control group was treated with rosuvastatin (5 mg/kg). At the end of the treatments, the renal function, electrocardiography, blood pressure, vascular reactivity, serum biochemical profile, and organ histopathology were evaluated. The main compounds identified in the essential oil of A. polystachya using gas chromatography coupled with mass spectrometry were beta-myrcene (1.08%), limonene (40.13%), and carvone (56.47%). The essential oil of A. polystachya not only lacks acute toxicity but also mitigates the reduction in the excretion of sodium, chloride, and creatinine in urine. Furthermore, it reduces electrocardiographic abnormalities and decreases blood pressure levels. Moreover, this treatment prevents an elevation in markers of inflammation and oxidative stress in the bloodstream. Our findings indicate significant cardioprotective effects of the essential oil of A. polystachya against multiple risk factors for cardiovascular diseases in hypertensive rats.

Ateroprotective effects of Plinia cauliflora in. New Zealand rabbits: beyond the lipid-lowering effect

Introduction: Plinia cauliflora [Mart.] Kausel (Myrtaceae), popularly known as "jabuticaba," is a fruit species native to Brazil. Despite extensive widespread usage, its antiatherosclerotic properties' impact remains unknown. Thus, the present study aimed to investigate the cardioprotective effects of a preparation obtained from the fruit peels of P. cauliflora (EEPC). Methods: Male New Zealand rabbits received a 1% cholesterol-supplemented diet for 60 days. On the thirtieth day, the animals were divided into five experimental groups and received, once a day, by the oral route, the EEPC (10, 30, and 100 mg/kg), simvastatin (2.5 mg/kg), or vehicle for 30 days. At the end of the experimental period, peripheral blood and arterial branch samples were collected. The levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), malondialdehyde (MDA), nitrotyrosine (NT), nitrite, interleukin 1 beta (IL-1b), interleukin 6 (IL-6), soluble inter-cellular adhesion molecule-1 (sICAM-1), and soluble vascular cell adhesion molecule-1 (sVCAM-1) levels were measured. Moreover, the catalase and superoxide dismutase levels were measured on the arterial samples. Histopathological analysis and arterial morphometry were also performed. Results and discussion: The oral administration of ESEG significantly lowered the levels of lipids in rabbits that were fed a CRD diet. This treatment also adjusted the protective system against oxidation in the arteries by decreasing the oxidation of lipids and proteins. Additionally, the levels of IL-1b, IL-6, sICAM-1, and sVCAM-1 in the bloodstream decreased significantly, and this was accompanied by a reduction of atherosclerotic lesions in all branches of the arteries. The findings suggest that EEPC may be a possible option for additional management of atherosclerosis.

Pharmacological Advances for Treatment in Hypertension

Hypertension plays a significant role in the development of cardiovascular disease and renal diseases, which can heighten the likelihood of experiencing related conditions like myocardial infarction, stroke, and heart failure [...].

Cardioprotective Effects of Solidago microglossa DC. in Nicotine-Treated Hypertensive Rats

Solidago microglossa DC. (Asteraceae), "arnica brasileira," is a Brazilian species popularly used to treat hypertension or renal ailments. This study investigated the cardioprotective effects of standardized S. microglossa extract (EESM) in nicotine-treated spontaneously hypertensive rats (SHRs). Moreover, the molecular mechanisms involved in the cardiovascular effects were also investigated. The acute toxicity was evaluated in female Wistar rats. Afterwards, six-month-old male spontaneously hypertensive rats received the EESM (14, 28, and 56 mg/kg), hydrochlorothiazide (25 mg/kg), and vehicle (filtered water; 0.1 mL/100 g) once daily for 28 days. All treatments were associated with 1.8 mg/kg of nicotine. At the end of the experimental period, the renal function, electrocardiographic profile, blood pressure, ventricular function, biochemical parameter, and mesenteric vascular bed reactivity were evaluated. Relative organ weights and cardiac morphometry were also investigated. Nicotine treatment in 6-month-old SHRs induced a significant reduction in renal function, with reduced urinary volume and lower renal elimination of sodium and creatinine. In addition, serum markers of the redox state and blood pressure levels remained significantly elevated, contributing to changes in vascular reactivity and left ventricular hypertrophy associated with reduced ventricular function. After 28 days of treatment, we found that the highest dose of EESM could mitigate all renal and cardiovascular changes developed by the nicotine-treated hypertensive rats. This study presented EESM as a possible cardioprotective drug that prevents cardiovascular dysfunctions in nicotine-treated hypertensive rats. Our data suggest EESM as a potential adjuvant therapy when cardioprotective effects are required.

The Cardiorenal Effects of Piper amalago Are Mediated by the Nitric Oxide/Cyclic Guanosine Monophosphate Pathway and the Voltage-Dependent Potassium Channels

Piper amalago L. is used in Brazilian traditional medicine to treat inflammation, chest pain, and anxiety. This study aimed to investigate the safety and the renal and cardiovascular effects of the volatile oil (VO) and the aqueous (AE) and hydroalcoholic (HE) extracts from P. amalago. The gas chromatography-mass spectrometry analyses identified 47 compounds in the VO, with β-cyclogermacrene, spathulenol, β-phellandrene, and α-pinene standing out. Among the 47 compounds also found in AE and HE by liquid chromatography-mass spectrometry, glycosylated flavones, organic acids, amino acids, and amides were highlighted. Some examples of these compounds are methoxy-methylenedioxy cis-cinnamoyl pyrrolidine, methoxy-methylenedioxy trans-cinnamoyl pyrrolidine, and cyclobutene-2,4-bis-(1,3-benzodioxol-5-methoxy-6-yl)-1,3-dicarboxapyrrolidide. The acute toxicity experiments were conducted on female rats (n = 5). The cardiorenal assays (n = 8) and evaluations of vasodilatory effects on the mesenteric vascular bed (n = 5) were conducted on male rats. In either extract or VO, there were no mortality or changes in relative weights or histopathological analysis of the organs. Urinary volume and renal electrolyte excretion were elevated significantly during repeated dose 7-day treatment with different preparations from P. amalago. None of the preparations induced hypotension or changes in cardiac electrical activity. Only HE promoted significant vasodilatory effects in rats' isolated mesenteric vascular beds. These effects were completely abolished in the presence of L-NAME plus 4-aminopyridine. Therefore, P. amalago leaves are safe and present diuretic activity after acute and repeated dose administration over 7 days. Moreover, the HE induced significant vasodilator response in rats' mesenteric vascular beds by NO/cGMP pathway and voltage-dependent K+ channels activation.

Role of K+ and Ca2+ Channels in the Vasodilator Effects of Plectranthus barbatus (Brazilian Boldo) in Hypertensive Rats

Plectranthus barbatus, popularly known as Brazilian boldo, is used in Brazilian folk medicine to treat cardiovascular disorders including hypertension. This study investigated the chemical profile by UFLC-DAD-MS and the relaxant effect by using an isolated organ bath of the hydroethanolic extract of P. barbatus (HEPB) leaves on the aorta of spontaneously hypertensive rats (SHR). A total of nineteen compounds were annotated from HEPB, and the main metabolite classes found were flavonoids, diterpenoids, cinnamic acid derivatives, and organic acids. The HEPB promoted an endothelium-dependent vasodilator effect (~100%; EC50 ~347.10 μg/mL). Incubation of L-NAME (a nonselective nitric oxide synthase inhibitor; EC50 ~417.20 μg/mL), ODQ (a selective inhibitor of the soluble guanylate cyclase enzyme; EC50 ~426.00 μg/mL), propranolol (a nonselective α-adrenergic receptor antagonist; EC50 ~448.90 μg/mL), or indomethacin (a nonselective cyclooxygenase enzyme inhibitor; EC50 ~398.70 μg/mL) could not significantly affect the relaxation evoked by HEPB. However, in the presence of atropine (a nonselective muscarinic receptor antagonist), there was a slight reduction in its vasorelaxant effect (EC50 ~476.40 μg/mL). The addition of tetraethylammonium (a blocker of Ca2+-activated K+ channels; EC50 ~611.60 μg/mL) or 4-aminopyridine (a voltage-dependent K+ channel blocker; EC50 ~380.50 μg/mL) significantly reduced the relaxation effect of the extract without the interference of glibenclamide (an ATP-sensitive K+ channel blocker; EC50 ~344.60 μg/mL) or barium chloride (an influx rectifying K+ channel blocker; EC50 ~360.80 μg/mL). The extract inhibited the contractile response against phenylephrine, CaCl2, KCl, or caffeine, similar to the results obtained with nifedipine (voltage-dependent calcium channel blocker). Together, the HEPB showed a vasorelaxant effect on the thoracic aorta of SHR, exclusively dependent on the endothelium with the participation of muscarinic receptors and K+ and Ca2+ channels.

Bridging the Gap: Exploring the Preclinical Potential of Pereskia grandifolia in Metabolic-Associated Fatty Liver Disease

Metabolic-associated fatty liver disease (MAFLD) is a complex condition characterized by steatosis and metabolic disturbances. Risk factors such as diabetes, cigarette smoking, and dyslipidaemia contribute to its development and progression. Effective and safe therapies for MAFLD are urgently needed. Pereskia grandifolia has shown potential as an alternative treatment, but its effectiveness against liver disease remains unexplored. This research aims to determine the hepatoprotective properties of P. grandifolia using a model of MAFLD. The study was carried out through various phases to assess the safety and efficacy of the ethanol-soluble fraction of P. grandifolia. Initially, an in vitro assay was performed to assess cell viability. This was followed by an acute toxicity test conducted in rats to determine the safety profile of the extract. Subsequently, the anti-inflammatory properties of P. grandifolia were examined in macrophages. For the MAFLD study, diabetic Wistar rats were made diabetic and exposed to a high fat diet and cigarette smoke, for 4 weeks. During the last 2 weeks, the rats were orally given either the vehicle (negative control group; C-), P. grandifolia (30, 100, and 300 mg/kg), or insulin in addition to simvastatin. A basal group of rats not exposed to these risk factors was also assessed. Blood samples were collected to measure cholesterol, triglycerides, glucose, ALT, and AST levels. Liver was assessed for lipid and oxidative markers, and liver histopathology was examined. P. grandifolia showed no signs of toxicity. It demonstrated anti-inflammatory effects by inhibiting phagocytosis and macrophage spreading. The MAFLD model induced liver abnormalities, including increased AST, ALT, disrupted lipid profile, oxidative stress, and significant hepatic damage. However, P. grandifolia effectively reversed these changes, highlighting its potential as a therapeutic agent. These findings emphasize the significance of P. grandifolia in mitigating hepatic consequences associated with various risk factors.

The Protective Effect of Citronellol against Doxorubicin-Induced Cardiotoxicity in Rats

Citronellol has been reported to have anti-inflammatory, anti-cancer, and antihypertensive activities, but its effect on myocardial ischemia is still unclear. The aim of this study was to investigate the therapeutic effects and pharmacological mechanisms of citronellol on ischemia. Therefore, a rat model of myocardial ischemia was established using the doxorubicin (DOX) model. To induce cardiotoxicity, the rats were given DOX (2.5 mg/kg) intraperitoneally over a 14-day period. Group I served as the control and received tween 80 (0.2%), group II received the vehicle and DOX, group III received the standard drug dexrazoxane and DOX, whereas groups IV, V, and VI were treated orally with citronellol (25, 50, and 100 mg/kg) and DOX, respectively. After treatment, the rats were euthanized, and blood samples were collected to assess the levels of serum cardiac markers, lipid profiles, and tissue antioxidant enzymes. The gene expressions of eNOS, PPAR-g, IL-10, VEGF, and NFkB-1 were also determined using real-time polymerase chain reactions. Simultaneous treatment with DOX and citronellol reduced cardiac antioxidant enzymes and lipid biomarkers in a dose-dependent manner. Citronellol also increased the expression of anti-inflammatory cytokines while reducing the expression of pro-inflammatory cytokines. Therefore, it can be concluded that citronellol may have potential cardioprotective effects in preventing DOX-induced cardiotoxicity.

Chemical Profiles and Cytotoxic Activities of Essential Oils from Six Species of Baccharis Subgenus Coridifoliae (Asteraceae)

Several Baccharis species are popularly known in traditional medicine as "carquejas", "vassouras", "ervas-santas" and "mio-mios", and are used as anti-inflammatories, digestives, and diuretics. This study aimed to investigate the chemical compositions and cytotoxic activities of essential oils (EOs) of six Baccharis species belonging to subgenus Coridifoliae, namely B. albilanosa, B. coridifolia, B. erigeroides, B. napaea, B. ochracea, and B. pluricapitulata. GC/MS analyses of the EOs showed that the oxygenated sesquiterpenes spathulenol (7.32-38.22 %) and caryophyllene oxide (10.83-16.75 %) were the major components for all the species. The EOs of almost all species were cytotoxic against cancer (BT-549, KB, SK-MEL and SK-OV-3) and normal kidney (VERO and LLC-PK1) cell lines, whereas B. erigeroides EO showed cytotoxicity only against LLC-PK1. This article augments the current knowledge about the chemical-biological properties of Baccharis subgenus Coridifoliae and discusses the therapeutic potentials of these economically unexploited plants.

Extraction Methods, Chemical Characterization, and In Vitro Biological Activities of Plinia cauliflora (Mart.) Kausel Peels

Plinia cauliflora (Mart.) Kausel, popularly known as jabuticaba, possesses bioactive compounds such as flavonoids, tannins, and phenolic acids, known for their antioxidant, antibacterial, wound healing, and cardioprotective effects. Therefore, this study aimed to standardize the P. cauliflora fruit peel extraction method, maximize phenolic constituents, and evaluate their antioxidative and antimicrobial effects. Various extraction methods, including vortex extraction with and without precipitation at 25, 40, and 80 °C, and infusion extraction with and without precipitation, were performed using a completely randomized design. Extraction without precipitation (E - P) showed the highest yield (57.9%). However, the precipitated extraction (E + P) method displayed a yield of 45.9%, higher levels of phenolic derivatives, and enhanced antioxidant capacity. Major compounds, such as D-psicose, D-glucose, and citric acid, were identified through gas chromatography-mass spectrometry (GC-MS) analysis. Ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis identified citric acid, hexose, flavonoids, tannins, and quercetin as the major compounds in the extracts. Furthermore, the extracts exhibited inhibitory effects against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli bacteria. In conclusion, the E + P method efficiently obtained extracts with high content of bioactive compounds showing antioxidant and antimicrobial capacities with potential application as a dietary supplement.

Bioprospecting a Film-Forming System Loaded with Eugenia uniflora L. and Tropaeolum majus L. Leaf Extracts for Topical Application in Treating Skin Lesions

Natural products can be used as complements or as alternatives to synthetic drugs. Eugenia uniflora and Tropaeolum majus are natives of Brazil and have antimicrobial, anti-inflammatory, and antioxidant activities. This study aimed to develop a film-forming system (FFS) loaded with plant extracts with the potential for treating microbial infections. E. uniflora and T. majus leaf extracts were prepared and characterized, and the individual and combined antioxidant and antimicrobial activities were evaluated. The FFS was developed with different concentrations of polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA) and analyzed for physicochemical characteristics. The combination of extracts showed a superior antioxidant effect compared to the individual extracts, justifying the use of the blend. FFS prepared with 4.5% PVA, 4.5% PVP, 7.81% E. uniflora extract, and 3.90% T. majus extract was adhesive, lacked scale formation, presented good malleability, and had a suitable pH for topical application. In addition, the viscosity at rest was satisfactory for maintaining stability; water solubility was adequate; skin permeation was low; and the antimicrobial effect was superior to that of the individual extracts. Therefore, the developed FFS is promising for the differentiated treatment of skin lesions through topical application.

Pulegone Prevents Hypertension through Activation of Muscarinic Receptors and Cyclooxygenase Pathway in L-NAME-Induced Hypertensive Rats

The current study was designed to determine pulegone's antihypertensive and vasoprotective activity in L-NAME-induced hypertensive rats. Firstly, the hypotensive dose-response relationship of pulegone was evaluated in normotensive anesthetized rats using the invasive method. Secondly, the mechanism involved in hypotensive activity was determined in the presence of pharmacological drugs such as atropine/muscarinic receptor blocker (1 mg/kg), L-NAME/NOS inhibitor (20 mg/kg), and indomethacin/COX inhibitor (5 mg/kg) in anesthetized rats. Furthermore, studies were carried out to assess the preventive effect of pulegone in L-NAME-induced hypertensive rats. Hypertension was induced in rats by administering L-NAME (40 mg/kg) orally for 28 days. Rats were divided into six groups which were treated orally with tween 80 (placebo), captopril (10 mg/kg), and different doses of pulegone (20 mg/kg, 40 mg/kg, and 80 mg/kg). Blood pressure, urine volume, sodium, and body weight were monitored weekly. After 28 days, the effect of pulegone on lipid profile, hepatic markers, antioxidant enzymes, and nitric oxide was estimated from the serum of treated rats. Moreover, plasma mRNA expression of eNOS, ACE, ICAM1, and EDN1 was measured using real-time PCR. Results show that pulegone dose-dependently decreased blood pressure and heart rate in normotensive rats, with the highest effect at 30 mg/kg/i.v. The hypotensive effect of pulegone was reduced in the presence of atropine and indomethacin, whereas L-NAME did not change its hypotensive effect. Concurrent treatment with pulegone for four weeks in L-NAME-treated rats caused a reduction in both systolic blood pressure and heart rate, reversed the reduced levels of serum nitric oxide (NO), and ameliorated lipid profile and oxidative stress markers. Treatment with pulegone also improved the vascular response to acetylcholine. Plasma mRNA expression of eNOS was reduced, whereas ACE, ICAM1, and EDN1 levels were high in the L-NAME group, which was facilitated by pulegone treatment. To conclude, pulegone prevented L-NAME-induced hypertension by demonstrating a hypotensive effect through muscarinic receptors and cyclooxygenase pathway, indicating its use as a potential candidate in managing hypertension.

Natural Products as Modulators of Mitochondrial Dysfunctions Associated with Cardiovascular Diseases: Advances and Opportunities

The mitochondria have an important role in modulating cell cycle progression, cell survival, and apoptosis. In the adult heart, the cardiac mitochondria have a unique spatial arrangement and occupy nearly one-third the volume of a cardiomyocyte, being highly efficient for converting the products of glucose or fatty acid metabolism into adenosine triphosphate (ATP). In cardiomyocytes, the decline of mitochondrial function reduces ATP generation and increases the production of reactive oxygen species, which generates impaired heart function. This is because mitochondria play a key role in maintaining cytosolic calcium concentration and modulation of muscle contraction, as ATP is required to dissociate actin from myosin. Beyond that, mitochondria have a significant role in cardiomyocyte apoptosis because it is evident that patients who have cardiovascular diseases (CVDs) have increased mitochondrial DNA damage to the heart and aorta. Many studies have shown that natural products have mitochondria-modulating effects in cardiac diseases, determining them as potential candidates for new medicines. This review outlines the leading plant secondary metabolites and natural compounds derived from microorganisms as modulators of mitochondrial dysfunctions associated with CVDs.

Bacopa monnieri in Patients with Parkinson's Disease: A Pilot Study

Bacopa monnieri (L.) Wettst. could be of interest in the control of symptoms of Parkinson's disease, but clinical evidence of its efficacy is lacking. This clinical trial assessed the effects of an extract of B. monnieri on parameters that are related to Parkinson's diseases. Twenty volunteers with Parkinson's disease were recruited for a primary, interventional, controlled, parallel, double-blind clinical study. The volunteers were assigned to treatment with either a commercial B. monnieri extract (225 or 450 mg/day) or placebo. The Parkinson's Disease Quality-of-Life (PDQL) questionnaire was applied, and motor activity was assessed before treatment and 30, 60, and 90 days after treatment with the B. monnieri extract or placebo. Characteristics such as age, body weight, and height were also collected. No differences in parkinsonian and systemic symptoms, emotional function, or social function were observed between. The delta percent (Δ%) showed time-dependent improvements in emotional function with B. monnieri treatment at the daily dose of 450 mg. A strong correlation was found between quality of life and motor outcomes at baseline and 30 days of treatment with B. monnieri, and a moderate correlation for 60 and 90 days of treatment with B. monnieri when compared with baseline time. A moderate correlation was found between motor outcomes and Hoehn and Yahr stages at baseline. Our results suggest that B. monnieri extract can improve emotional function in Parkinson's disease patients, but further clinical trials are needed to confirm this possibility.

The NO-cGMP-K+ Channel Pathway Participates in Diuretic and Cardioprotective Effects of Blutaparon portulacoides in Spontaneously Hypertensive Rats

Blutaparon portulacoides is a Brazilian plant species that is widely used in folk medicine. The present study investigated the role of an aqueous extract of B. portulacoides against hypertension in spontaneously hypertensive rats. The aqueous extract of B. portulacoides was obtained from the whole plant. Its chemical profile was analyzed by ultraperformance liquid chromatography-tandem mass spectrometry. The acute toxicity of the aqueous extract of B. portulacoides was evaluated in female Wistar rats. Male 6-month-old spontaneously hypertensive rats then received the aqueous extract of B. portulacoides (30, 100, and 300 mg/kg), hydrochlorothiazide (25 mg/kg), or vehicle once daily for 28 days. On days 1, 14, and 28, the diuretic effects of the aqueous extract of B. portulacoides were evaluated. The role of prostaglandins and the nitric oxide-cyclic guanosine monophosphate-potassium channel pathway in the diuretic activity of the aqueous extract of B. portulacoides was also investigated. At the end of the treatment, hepatic and renal biochemical markers, serum nitrotyrosine, malondialdehyde, nitrite, and aldosterone levels, and angiotensin-converting enzyme activity were measured. The electrocardiographic profile, blood pressure, and renal vascular reactivity were also assessed. The heart, kidneys, and liver were collected to determine relative organ weight, histopathology, and cardiac morphometry. Caffeic acid, ferulic acid, and several flavonoids were identified in the aqueous extract of B. portulacoides. No signs of toxicity were observed. Prolonged treatment with the aqueous extract of B. portulacoides (300 mg/kg) induced significant diuretic activity by activating the nitric oxide-cyclic guanosine monophosphate-potassium channel pathway. These effects reduced blood pressure and oxidative stress and prevented renal vascular dysfunction and left ventricular hypertrophy that was induced by hypertension. Overall, the present data suggest that the aqueous extract of B. portulacoides has important diuretic and cardioprotective effects by activation of the nitric oxide-cyclic guanosine monophosphate-potassium channel pathway.

Small conductance calcium-activated potassium channels and nitric oxide/cGMP pathway mediate cardioprotective effects of Croton urucurana Baill. In hypertensive rats

ETHNOPHARMACOLOGICAL RELEVANCE

Croton urucurana Baill. (Euphorbiaceae), popularly known as 'sangue de dragão' is a Brazilian species widely used in traditional medicine for cardiovascular ailments.

AIM

To investigate the cardiovascular effects of the C. urucurana extract in spontaneously hypertensive rats (SHRs).

MATERIALS AND METHODS

Leaves from C. urucurana were collected and morphoanatomically characterized. The ethanol-soluble fraction (ESCU) was obtained and analyzed by LC-DAD-MS. Using female Wistar rats we investigated the acute toxicity of ESCU. Then, SHRs (six months old) received vehicle, hydrochlorothiazide (25 mg/kg), or ESCU (30, 100, 300 mg/kg) for 28 days. At the beginning and at the end of treatments, urine samples were obtained to assess renal function. At the end of the trial period, the blood pressure, mesenteric vascular beds (MVBs) reactivity, and electrocardiographic profile were evaluated. Serum angiotensin-converting enzyme activity, as well as urea, creatinine, sodium, potassium, nitrite, malondialdehyde, nitrotyrosine, and aldosterone levels were determined. Relative organ weights and histopathological analysis were performed. Finally, the cardiac function on a Langendorff system, as well as the molecular mechanisms involved in the vasodilator effects of ESCU in MVBs were also investigated.

RESULTS

The compounds annotated from ESCU by LC-DAD-MS included mainly phenylpropanoid derivatives, alkaloids, O-glycosylated megastigmanes, glycosylated flavonoids, flavan-3-ols, and others, such as quercetin O-deoxyhexosyl-hexoside, magnoflorine, reticuline, and taspine. None of the animals showed any signs of toxicity. Male SHRs treated only with the vehicle showed important cardiovascular changes, including a reduction in renal function, increase in serum oxidative stress, and hemodynamic, electrocardiographic, and morphological changes typical of hypertensive disease. Moreover, parameters of cardiac function, including left ventricular developed pressure, peak rate of contraction, peak rate of relaxation, and the rate pressure product were significantly altered, showing a significant impairment of ventricular function. All ESCU-doses presented a significant cardioprotective effect in SHRs rats. The 28-day treatment normalized the hemodynamic, electrocardiographic, morphological, and renal impairments, as well as reversed the changes in ventricular function induced by hypertension. In MVBs with an intact endothelium, ESCU (0.1, 0.3, and 1 mg) dose-dependently induced vasodilation. Endothelium removal or the inhibition of nitric oxide synthase prevented the vasodilatory effect of ESCU. Perfusion with a physiological saline solution that contained KCl, tetraethylammonium, or apamin also abolished the vasodilatory effect of ESCU.

CONCLUSION

Prolonged ESCU-treatment showed significant cardioprotective effects in SHRs. Moreover, the data showed the role of nitric oxide and calcium-activated small conductance potassium channels in the cardiovascular effects of ESCU.

A New Approach for the Development of Multiple Cardiovascular Risk Factors in Two Rat Models of Hypertension

Cardiovascular disease (CVD) is the leading cause of death among non-communicable diseases. There is a lack of valid animal models that mimic associations among multiple cardiovascular risk factors in humans. The present study developed an animal model that uses multiple cardiovascular risk factors—namely, hypertension, hypothyroidism, and a high-fat diet (HFD). Two models of hypertension were used: renovascular hypertension (two-kidney, one clip [2K1C]) and spontaneously hypertensive rats (SHRs). The naive group was composed of normotensive rats. Twelve weeks after surgery to induce renovascular hypertension, rats in the 2K1C and SHR groups underwent thyroidectomy. The HFD was then implemented for 6 weeks. Renal function, serum redox status, biochemical CVD markers, electrocardiographic profile, blood pressure, mesenteric vascular bed reactivity, histopathology, and morphometry were investigated. Both experimental models induced dyslipidemia, renal function impairment, and hepatic steatosis, accompanied by higher levels of different inflammatory markers and serum oxidative stress. These alterations contributed to end-organ damage in all hypertensive rats. Our findings corroborate a viable alternative model that involves multiple cardiovascular risk factors and resembles conditions that are seen in humans. Both models mimicked CVD, but our data show that SHRs exhibit more significant pathophysiological changes.

Herbal Medicines in the Treatment of Dyspepsia: An Overview

This review focuses on the efficacy of herbal medicines for managing dyspepsia in humans and animals. Searches were conducted on the PubMed, Science Direct, and Medline databases, for publications in the last 3 years. In each database, the search terms used consisted of the 2 key terms describing the disorder and subtypes plus each of the terms relating to the therapy. The key terms used were "natural product" and "medicinal plant" in a cross-over with "dyspepsia" and "functional dyspepsia" (i.e., gastroprotection, Helicobacter pylori infection, prokinetic). We included all human and animal studies on the effects of herbal medicines reporting the key outcome of dyspepsia symptoms. Preclinical studies using critically validated models showed that most medicinal plants with gastroprotective action had antioxidant, anti-inflammatory, anti-apoptotic, and antisecretory effects. Moreover, several species displayed anti Helicobacter pylori and prokinetic efficacy. The data availability of controlled clinical studies is currently minimal. The use of different methodologies and the minimal number of patients raise doubts about the effects of these preparations. Only adequate clinical trials with scientifically validated methods can determine whether different herbal medicines can be used as viable alternatives to the conventional pharmacological treatments used to control dyspepsia symptoms.

Croton urucurana Baill. Ameliorates Metabolic Associated Fatty Liver Disease in Rats

Background: Metabolic associated fatty liver disease (MAFLD) affects a quarter of the worldwide population, but no drug therapies have yet been developed. Croton urucurana Baill. (Euphorbiaceae) is a medicinal species, that is, widely distributed in Brazil. It is used in popular medicine to treat gastrointestinal, cardiovascular, and endocrine system diseases. However, its hepatoprotective and lipid-lowering effects have not yet been scientifically investigated.

Aim of the study: The present study investigated the effects of an extract of C. urucurana in a rat model of MAFLD that was associated with multiple risk factors, including hypertension, smoking, and dyslipidemia.

Material and Methods: The phytochemical composition of C. urucurana was evaluated by liquid chromatography-mass spectrometry. Spontaneously hypertensive rats received a 0.5% cholesterol-enriched diet and were exposed to cigarette smoke (9 cigarettes/day for 10 weeks). During the last 5 weeks, the animals were orally treated with vehicle (negative control [C-] group), C. urucurana extract (30, 100, and 300 mg/kg), or simvastatin + enalapril (two standard reference drugs that are commonly used to treat dyslipidemia and hypertension, respectively). One group of rats that were not exposed to these risk factors was also evaluated (basal group). Blood was collected for the analysis of cholesterol, triglyceride, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels. The liver and feces were collected for lipid quantification. The liver was also processed for antioxidant and histopathological analysis.

Results: The main constituents of the C. urucurana extract were flavonoids, glycosides, and alkaloids. The model successfully induced MAFLD, reflected by increases in AST and ALT levels, and induced oxidative stress in the C- group. Treatment with the C. urucurana extract (300 mg/kg) and simvastatin + enalapril decreased plasma and hepatic lipid levels. In contrast to simvastatin + enalapril treatment, C. urucurana reduced AST and ALT levels. Massive lesions were observed in the liver in the C- group, which were reversed by treatment with the C. urucurana extract (300 mg/kg).

Conclusion:C. urucurana extract exerted promising hepatoprotective and lipid-lowering effects in a preclinical rat model of MAFLD.

Cardioprotective effects of Talinum paniculatum (Jacq.) Gaertn. in doxorubicin-induced cardiotoxicity in hypertensive rats

ETHNOPHARMACOLOGICAL RELEVANCE

Talinum paniculatum (Jacq.) Gaertn. (Talinaceae) is a medicinal species that is widely distributed throughout Brazil. Popularly known as "major-gomes," the species is used in folk medicine for the treatment of cardiovascular disorders.

AIM OF THE STUDY

To evaluate the effect of an ethanolic extract of T. paniculatum (EETP) in rats with renovascular hypertension and heart failure and determine its chemical composition.

MATERIALS AND METHODS

First, EETP was obtained, and its chemical profile was analyzed by LC-DAD-MS. The acute toxicity was evaluated in female Wistar rats. The model of renovascular hypertension was established in male Wistar rats by combining the Goldblatt 2K1C method and intraperitoneal doxorubicin administration for 6 weeks. The animals were then treated daily with EETP (30, 100, and 300 mg/kg) or metoprolol (25 mg/kg) by gavage for 28 days. The negative control group was treated with vehicle (filtered water). The sham group consisted of animals that were not subjected to 2K1C or cardiotoxicity and were treated with vehicle. Renal function was evaluated on days 1, 14, and 28. At the end of treatment, the electrocardiographic profile, blood pressure, and mesenteric vascular reactivity were investigated. Serum urea, creatinine, angiotensin converting enzyme, nitrotyrosine, malondialdehyde, nitrite, aldosterone, and sodium and potassium levels were measured. The heart, aorta artery, liver, and right kidney were collected, weighed, and processed for histopathological analysis. Cardiac chambers also underwent morphometric analysis.

RESULTS

No signs of toxicity were observed in female Wistar rats. Thirty-two compounds were annotated from EETP, including flavonoids, chlorogenic acids, and saponins. EETP treatment resulted in a significant cardiorenal-protective response, normalizing electrocardiographic and hemodynamic alterations, and preventing ventricle remodeling. These effects were associated with serum antioxidant activity and angiotensin-converting enzyme (ACE) inhibition.

CONCLUSION

The present study demonstrated that EETP may exert cardioprotective effects through serum antioxidant activity and ACE inhibition, preventing alterations of hemodynamic and endothelial function, and reducing damage to cardiac structure. Thus, EETP, especially at the 100 and 300 mg/kg doses, may be useful for preventing doxorubicin-induced cardiotoxicity in hypertensive patients.

Tagetes erecta L. flowers, a medicinal plant traditionally used to promote diuresis, induced diuretic and natriuretic effects in normotensive and hypertensive rats

ETHNOPHARMACOLOGICAL RELEVANCE

Tagetes erecta L., known as marigold, belongs to the Asteraceae family and is mainly found in South America. Despite reports that T. erecta flowers are used in folk medicine to treat cardiovascular and renal diseases, there is no study regarding its diuretic effect.

AIM

This study aimed to evaluate the chemical composition and the diuretic efficacy of the hydroethanolic extract from T. erecta (HETE) in normotensive (NTR) and hypertensive (SHR) rats.

MATERIAL AND METHODS

The HETE was analyzed by liquid chromatography coupled to diode array detector and mass spectrometry (LC-DAD-MS). Female and male NTR and SHR received the treatment with vehicle, HETE (0.01 mg/kg, 0.1 mg/kg, and 1 mg/kg) or hydrochlorothiazide (HCTZ; 5 mg/kg) orally. The urinary parameters were measured at the end of the 8-h experiment.

RESULTS

From HETE, saccharides and triterpenes were the main annotated compounds, such as erythrodiol and β-amyrin. The urine volume was significantly increased in the groups treated with HETE, in both male and female NTR and SHR rats, compared to the respective vehicle-treated groups. Regarding electrolytes elimination, the treatment with HETE did not reveal significant changes in the urine levels of K⁺ or Cl^-, but it showed a natriuretic and Ca²⁺-sparing effects. The HETE beneficial result in reducing Ca²⁺ excretion was confirmed through the protective effect found in front of the urinary calcium oxalate precipitation and crystallization. The combination with HCTZ, a classic diuretic and saluretic medicine, significantly enhanced HETE-induced diuresis, natriuresis, and the Ca²⁺-sparing effect. On the other hand, the K⁺-sparing action was improved in the combination of HETE with amiloride, a standard K⁺-sparing diuretic. In contrast, the combination of HETE with atropine (a non-selective muscarinic receptor antagonist) and indomethacin (an inhibitor of the cyclooxygenase enzyme), promoted an important reduction in urinary volume, but interestingly the natriuretic effect was maintained.

CONCLUSION

This study contributed to the preclinical validation of the diuretic efficacy of T. erecta, highlighting this species as promising for the development of new pharmacological strategies for the management of kidney disorders.

Therapeutic Feasibility of the Natural Products in the Heart Complaints: An Overview

Heart pain is the most frequent complaint leading patients to seek medical help. Functional heart symptoms, especially chest pain, are prevalent and, according to the International Classification of Diseases (ICD-10), are described as "somatoform autonomous functional disorders of the cardiovascular system." The problem lies in the fact that pain does not always have a somatic background, that is, it may be related to crucial underlying heart disease. The population does not know how to differentiate somatic pain from significant ischemic symptoms, and based on the patient's complaints, traditional medicine ends up treating other underlying cardiac diseases. Many unsuccessful unconventional therapies have been proposed in recent years, including herbal medicines that seek to disrupt the disease's pathogenesis. The present review summarizes research carried out in the last 5 years on natural products' heart complaints, including myocardial ischemia, arrhythmia, and heart failure. Several herbal medicines may be used as a replacement or complementary treatment strategy. A total of 17 medicinal plants have shown promising results in preclinical studies. However, human clinical trials are scarce; only two have been presented. Generally, the data are bland, and many issues have been raised about herbal therapies' safety, efficacy, and mode of action. Besides, relevant clinical trials, future perspectives, and possible clinical applications are discussed.

Prolonged Administration of Rudgea viburnoides (Cham.) Benth. Prevents Impairment of Redox Status, Renal Dysfunction, and Cardiovascular Damage in 2K1C-Hypertensive Rats by Inhibiting ACE Activity and NO-GMPC Pathway Activation

Rudgea viburnoides is widely found in the Brazilian Cerrado, and commonly used in Brazilian folk medicine. In this study, we evaluated the effects of prolonged administration of the aqueous extract from R. viburnoides leaves (AERV) on impaired redox status, renal dysfunction, and cardiovascular damage in 2K1C hypertensive rats, as well as its chemical composition by LC-DAD-MS. Renal hypertension (two kidney, one-clip model) was surgically induced in male Wistar rats and AERV (30, 100 and 300 mg/kg) was administered orally five weeks after surgery for 28 days. Renal function was assessed and urinary electrolytes, pH, and density were measured. Electrocardiography, blood pressure and heart rate were recorded. Cardiac and mesenteric vascular beds were isolated for cardiac morphometry and evaluation of vascular reactivity, and aortic rings were also isolated for measurement of cyclic guanosine monophosphate levels, and the redox status was assessed. Prolonged treatment with AERV preserved urine excretion and electrolyte levels (Na+, K+, Ca2+ and Cl-), reversed electrocardiographic changes, left ventricular hypertrophy and changes in vascular reactivity induced by hypertension, and reduced blood pressure and heart rate. This effect was associated with a positive modulation of tissue redox state, activation of the NO/cGMP pathway, and inhibition of the angiotensin-converting enzyme. Glycosylated iridoids, chlorogenic acids, glycosylated triterpenes, O-glycosylated flavonols, and triterpenoid saponins were annotated. AERV showed no acute toxicity in female Wistar rats. Therefore, AERV treatment reduced the progression of cardiorenal disease in 2K1C hypertensive rats, which can be involved with an important attenuation of oxidative stress, angiotensin-converting enzyme inhibition, and activation of the NO/cGMP pathway.

Ethnopharmacological investigation of the cardiovascular effects of the ethanol-soluble fraction of Aloysia polystachya (Griseb.) Moldenke leaves in spontaneously hypertensive rats

ETHNOPHARMACOLOGICAL RELEVANCE

Aloysia polystachya (Griseb) Moldenke (Verbenaceae), popularly known as "burrito", is a South American species widely prescribed by local Brazilian healers for the treatment of cardiovascular diseases. However, its antihypertensive and cardioprotective effects are still unknown.

AIM

To evaluate the role of the ethanol-soluble fraction of A. polystachya leaves (ESAP) against hypertension in spontaneously hypertensive rats (SHRs), as well as its safety, morphoanatomical and phytochemical aspects.

MATERIALS AND METHODS

First, the leaves and stems of A. polystachya were analyzed by optical and scanning electron microscopy in order to provide anatomical data for quality control. Then, ESAP was obtained and its chemical profile was analyzed by LC-DAD-MS. In addition, the cytotoxic and acute toxicity potential of ESAP were evaluated in six cell lines and in female Wistar rats, respectively. Next, female spontaneously hypertensive rats (SHRs) received ESAP (30, 100, 300 mg/kg), hydrochlorothiazide (25 mg/kg), or vehicle once daily for 28 days. Weekly kidney function was monitored by analyzing urinary parameters. At the end of the 28-day treatment, the electrocardiographic profile, blood pressure, and renal and mesenteric vascular reactivity were evaluated. Relative organ (heart, kidney, and liver) weights and biochemical parameters were also evaluated. Finally, the heart, kidneys, and aorta were collected for determination of the tissue redox state, cardiac morphometry, and histopathological analysis.

RESULTS

The chemical profile of ESAP was composed by organic acids, a nucleoside, methoxylated flavones and glycosylated compounds including phenolic acids, phenylpropanoids, iridoids and monoterpenes. No signs of toxicity were observed in all cell's lines nor in female Wistar rats submitted to this trial. All SHRs from the negative control group presented a reduction in renal function, alterations in the renal and mesenteric vascular reactivity, and electrocardiographic and morphometric changes typical of ventricular hypertrophy. Oral prolonged ESAP-administration in SHRs was able to reverse renal, electrocardiographic and hemodynamic changes induced by hypertension. Moreover, ESAP-treatment was able to modulate the vascular and renal arterial reactivity and tissue redox state. The aforementioned data were accompanied by reduction of cardiac hypertrophy.

CONCLUSION

In this study, we present important anatomical and phytochemical data that contributed to the correct identification and quality control of A. polystachya. In addition, we have shown that ESAP is safe after acute administration and present significant cardioprotective effects (at 30, 100, and 300 mg/kg doses) in SHRs after prolonged treatment.

Hepato- and cardioprotective effects of Baccharis trimera (Less.) DC. against multiple risk factors for chronic noncommunicable diseases

Cardiovascular diseases are associated with high morbidity and mortality worldwide and have several risk factors, including dyslipidemia, smoking, and hypertension. Studies have evaluated isolated risk factors in experimental models of cardiovascular disease, but few preclinical studies have assessed associations between multiple risk factors. In the present study, hypertensive Wistar rats (Goldblatt 2K1C model) received a 0.5% cholesterol diet and were exposed to tobacco smoke for 8 weeks. During the last 4 weeks, the animals were treated with vehicle, an ethanol-soluble fraction of B. trimera (30, 100, and 300 mg/kg), or simvastatin + enalapril. A group of normotensive, non-dyslipidemic, and non-smoking rats was treated with vehicle. The levels of aspartate aminotransferase, alanine aminotransferase, urea, creatinine, and hepatic and fecal lipids, blood pressure, and mesenteric arterial bed reactivity were evaluated. Cardiac, hepatic, and renal histopathology and tecidual redox state were also investigated. Untreated animals exhibited significant changes in blood pressure, lipid profile, and biomarkers of heart, liver, and kidney damage. Treatment with B. trimera reversed these changes, with effects that were similar to simvastatin + enalapril. These findings suggest that B. trimera may be promising for the treatment of cardiovascular and hepatic disorders, especially disorders that are associated with multiple risk factors.

Natural Agents Modulating ACE-2: A Review of Compounds with Potential against SARS-CoV-2 Infections

One of the biggest challenges of public health worldwide is reducing the number of events and deaths related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. The angiotensinconverting enzyme 2 (ACE-2), a carboxypeptidase that degrades angiotensin II into angiotensin 1-7, has been identified as a potent receptor for SARS-CoV-2. In the last decades, ACE inhibition has assumed a central role in reducing cardiovascular and renal events. However, with the advent of COVID-19, attention has been turned to ACE-2 as a possible target to reduce virus binding to different human cells. This review aims to discuss recent developments related to the medicinal properties of natural compounds as ACE/ACE-2 inhibitors, which should be highlighted in the future development of studies looking for modulators in SARS-CoV-2 infection. Data show that bioactive compounds isolated from several natural products act by inhibiting ACE/ACE-2, which changes the entire axis of this system. Of the compounds addressed in this review, 7 phenolic compounds, including quercetin, curcumin, naringenin, luteolin, hesperidin, mangiferin, and gallic acid showed binding affinity with molecular ACE-2 target in silico, and 1, esculetin, decreased ACE-2 expression in vivo. Regarding terpenoids and alkaloids, nimbin, withaferin A, andrographolide, zingiberene and, berberine, piperine and thebaine, respectively, showed a binding affinity with molecular ACE-2 target in silico. These findings reinforce the need for future preclinical and clinical studies on these compounds and specific inhibitory effects on ACE-2 of all the other compounds described herein only as nonspecific ACE inhibitors. It is important to mention that some natural compounds such as magnolol, resveratrol, rosmarinic acid, tanshinone IIA, and nicotine have also demonstrated the potential to increase the activity or expression of ACE-2, and could therefore aggravate SARS-CoV-2 infection.

Endothelium-independent vasorelaxant effect of Asphodelus tenuifolius Cav. via inhibition of myosin light chain kinase activity in the porcine coronary artery

ETHNOPHARMACOLOGICAL RELEVANCE

Asphodelus tenuifolius Cav. (Asphodelaceae), a wild, terrestrial, annual stemless herb, is widely used in traditional medicine for the treatment of hypertension, diabetes, atherosclerosis and circulatory problems. A previous research study from our laboratory revealed that A. tenuifolius has beneficial effects in reducing blood pressure and improves aortic endothelial dysfunction in chronically glucose fed rats. Despite the fact that A. tenuifolius reduces blood pressure and improves endothelial function in vivo, there are no detailed studies about its possible mechanism of action.

AIM OF THE STUDY

This study was designed to provide pharmacological basis and mechanism of action for the traditional use of A. tenuifolius in hypertension and circulatory problems. We explored the vasorelaxant effect of A. tenuifolius and its underlying vasorelaxation mechanism in porcine coronary artery rings.

MATERIALS AND METHODS

Aqueous methanolic crude extract of A. tenuifolius was prepared by maceration process and then activity guided fractionation was carried out by using different polarity based solvents. Phytochemical studies were carried out using LC-DAD-MS. Segments of porcine distal coronary artery were set up in a wire myograph for isometric force measurements. Extract/fractions of A. tenuifolius seeds were tested for vasodilator activity by measurement of changes in tone after pre-contraction with the thromboxane mimetic U46619 in the presence or absence of inhibitors of intracellular signaling cascades.

RESULTS

Crude extract/fractions of A. tenuifolius produced dose dependent endothelium independent vasorelaxant response in coronary rings, whereas, the butanol fraction of A. tenuifolius (BS-AT) produced the largest relaxation response with 100% relaxation at 1 mg/ml, therefore the mechanism of relaxation of this fraction was determined. The relaxation to BS-AT was unaffected by removal of the endothelium, pre-contraction with KCl, or the presence of the non-selective potassium channel blocker tetraethylammonium, indicating that the relaxation was endothelium-independent, and does not involve activation of potassium channels. BS-AT (1 mg/ml) inhibited the contractile response to calcium,the L-type calcium channel activator BAY K8664,and ionomycin, indicating that it inhibits calcium-induced contractions. The relaxation response to BS-AT was attenuated in the absence of extracellular calcium. However, relaxations to BS-AT were also reduced after deletion of calcium from intracellular stores with cyclopiazonic acid. Incubation with 1 mg/ml BS-AT also inhibited phosphorylation of myosin light chains in homogenates of coronary artery.

CONCLUSION

The butanol extract of Asphodelus tenuifolius produces a large endothelium-independent relaxation of the porcine coronary artery through inhibition of calcium-induced contractions. The effect appears to be downstream of calcium influx, possibly through inhibition of myosin light chain kinase. This study supports previous studies demonstrating that A. tenuifolius reduces blood pressure. Future studies will aim to determine the active compounds underlying this response.

Epigenetic control of hypertension by DNA methylation: A real possibility?

Hypertension is a common chronic disease that particularly affects the elderly and can trigger several cardiovascular conditions. Although the treatment of hypertension has evolved in recent decades, many hypertensive patients still do not have properly controlled blood pressure. Accumulating evidence supports the hypothesis that DNA methylation plays an important role in regulating gene expression, altering the phenotype and function of the cardiovascular system. The present review highlights recent advances in research on DNA methylation in the development of hypertension. Several preclinical and clinical evidence show that methylation of different targets appears to be involved in hypertension. Studies of the involvement of DNA methylation have greatly improved our understanding of hypertension, but its use as a valid therapeutic target is still unknown. Further studies could help to bring to light the truth about gene therapy in hypertension.

Anti-inflammatory Properties of Ethanolic Extract and 2″-O-β-D-Glucopyranosyl-vitexin Obtained from Alternanthera tenella Colla Whole Plant

Six flavonoids were identified and isolated from the ethanolic extract of Alternanthera tenella Colla (Amaranthaceae) whole plant (EEAT) including 2″-O-β-D-glucopyranosyl-vitexin (A19). Flavonoids have anti-inflammatory activity; however, the 2″-O-β-D-glucopyranosyl-vitexin anti-inflammatory property was not totally explored. The aim of the present study was to investigate the anti-inflammatory effects of ethanolic extract from A. tenella whole plant and isolated flavone C-glycoside A19 in models of inflammation. The oral administration (p.o.) of EEAT (30, 100, and 300 mg/kg), A19 (0.1, 1, and 10 mg/kg), and prednisolone (3 mg/kg) were tested against the carrageenan-induced paw edema in Swiss mice. The EEAT (100 mg/kg, p.o.), A19 (1 mg/kg, p.o.), and prednisolone (3 mg/kg, p.o.) were tested in the zymosan-articular inflammation, carrageenan-pleurisy, and complete Freund's adjuvant (CFA) models in Swiss mice. In silico analysis and search for structural relationships between vitexin derivatives flavones present in the EEAT and TNF-α inhibitors were performed. EEAT, A19, and prednisolone significantly inhibited (i) edema, mechanical hyperalgesia in carrageenan-induced paw inflammation; (ii) leukocyte migration and protein extravasation in carrageenan-induced pleurisy; (iii) knee edema, mechanical hyperalgesia, and leukocyte migration in articular inflammation induced by zymosan. Still the CFA induced the increase in myeloperoxidase and N-acetylglucosaminidase activities, EEAT, A19, and prednisolone significantly inhibited these enzymes. The in silico analysis showed that molecules with similar structure to apigenin and vitexin have a potential inhibition on the TNF system. This study confirms the anti-inflammatory properties of EEAT and A19. The C-glycosylated flavone A19 could be responsible for the EEAT anti-edematogenic and anti-hyperalgesic effects and a potential TNF-α inhibitor.

Nephroprotective and antilithiatic activities of Costus spicatus (Jacq.) Sw.: Ethnopharmacological investigation of a species from the Dourados region, Mato Grosso do Sul State, Brazil

ETHNOPHARMACOLOGICAL RELEVANCE

Costus spicatus (Jacq.) Sw., also known as "cana-do-brejo," is a species that is widely used in Brazilian traditional medicine for the treatment of kidney diseases. However, no studies have evaluated its nephroprotective and antilithiatic effects.

AIM

To investigate nephroprotective and antilithiatic effects of C. spicatus in a preclinical model of acute kidney injury (AKI) and in vitro nephrolithiasis.

MATERIALS AND METHODS

C. spicatus leaves were collected directly from the natural environment in the Dourados region, Mato Grosso do Sul State, Brazil. The ethanol-soluble fraction of C. spicatus (ESCS) was obtained by infusion. Phytochemical characterization was performed by liquid chromatography coupled to diode array detector and mass spectrometer (LC-DAD-MS). We assessed whether ESCS has acute or prolonged diuretic activity. The nephroprotective effects of ESCS were evaluated in a model of AKI that was induced by glycerol (10 ml/kg, intramuscularly) in Wistar rats. Different doses of ESCS (30, 100, and 300 mg/kg) were administered orally for 5 days before the induction of AKI. Urinary parameters were measured on days 1, 3, 5, and 7. Twenty-four hours after the last urine collection, blood samples were obtained for the biochemical analysis. Blood pressure levels, renal vascular reactivity, renal tissue redox status, and histopathological changes were measured. Antilithiatic effects were evaluated by in vitro crystallization. Calcium oxalate precipitation was induced by sodium oxalate in urine samples with ESCS at 0.05, 0.5, and 5 mg/ml.

RESULTS

From LC-DAD-MS analyses, flavonoids, saponins and other phenolic compounds were determined in the composition of ESCS. Significant reductions of the excretion of urinary total protein, creatinine, sodium, and potassium were observed in the AKI group, with significant histopathological damage (swelling, vacuolization, necrosis, and inflammatory infiltration) in the proximal convoluted tubule. Treatment with ESCS exerted a significant nephroprotective effect by increasing the urinary excretion of total protein, urea, creatinine, sodium, potassium, calcium, and chloride. All of the groups that were treated with ESCS exhibited a reduction of histopathological lesions and significant modulation of the tissue redox state. We also observed a concentration-dependent effect of ESCS on the crystallization of urinary crystals, with reductions of the size and proportion of monohydrated crystals.

CONCLUSION

The data suggest that C. spicatus has nephroprotective and antilithiatic effects, suggesting possible effectiveness in its traditional use.

Genotoxicity Study of Vitex megapotamica (Spreng.) Moldenke

Vitex megapotamica (Spreng) Moldenke is commonly known as tarumã, it is an important medicinal and edible fruit plant. It is native to regions of tropical and subtropical climate in greater proportion than temperate zones and widely distributed in Central America, South America, Asia, and Africa. In Brazil, it is present in the Atlantic Forest and Cerrado biomes. Despite its widespread use, there are no minimum standards for quality control or information on genotoxicity. Therefore, the aim of this study was to present a detailed description of the short-term genotoxicity assays of V. megapotamica and to provide parameters of a preparation routinely used in traditional folk medicine. For genotoxicity assays, five groups were used with eight wistar rats in each group. For this, three doses of the V. megapotamica extract in doses (100, 300, and 900 mg/kg) or negative control (filtered water) were administered orally and positive control cyclophosphamide monohydrate (20 mg/kg; Sigma-Aldrich^®) was applied by the intraperitoneal route after 24 h. At the end, whole blood was collected in a tube containing EDTA for the comet test and later the animals were euthanized. For the micronucleus test, femurs were removed, and bone marrow was collected. In the comet assay, V. megapotamica crude extract did not show significant DNA damage at all doses tested. The micronucleus assay showed no significant increase in the frequency of inducing micronuclei at any dose examined. It can be concluded that the safety parameters in genotoxicity studies reveal that V. megapotamica has no toxicity, which characterizes the important quality control of this plant species.

Repeated dose 90-day oral toxicity study of Vitex megapotamica (Spreng.) Moldenke

Vitex megapotamica (Spreng.) Moldenke is a plant with medicinal properties popularly used in Brazil to treat diabetes and obesity. Despite the promising use of this plant, are still incipient toxicology studies on prolonged periods of treatment. The aim of this study was to evaluate the repeated dose 90-day oral toxicity study of V. megapotamica methanolic extract (VMME) in male and female Wistar rats. Different groups of rats (n = 8) were treated daily with three different doses of VMME (100, 300, and 900 mg/kg) or vehicle (filtered water). Body weight, water, and feed consumption, and clinical and behavioral changes were monitored daily. At the end of the experimental period, blood samples were obtained for hematological and biochemical analyzes. After euthanasia, the vital organs were removed for the determination of relative weight and for histopathological analysis. No clinical signs of toxicity or mortality were found during the experimental period. Treatment with VMME did not induce any change in body weight gain, eating patterns, and behavior. We found no statistically significant changes in the different hematological and biochemical parameters evaluated. The relative weight of the organs and histopathological analysis did not show any significant change when compared to animals treated with the vehicle. The data obtained in this study allow us to conclude that the VMME obtained from V. megapotamica is safe after a repeated-dose 90-day oral toxicity study in male and female Wistar rats.

Repurposing Drugs for the Management of Patients with Confirmed Coronavirus Disease 2019 (COVID-19)

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), termed coronavirus disease 2019 (COVID-19) by the World Health Organization, is a newly emerging zoonotic agent that emerged in China in December 2019. No specific treatment for COVID-19 is currently available. Usual palliative treatment includes maintaining hydration and nutrition and controlling fever and cough. The clinical severity and extent of transmission need to be determined, and therapeutic options need to be developed and optimized.

METHODS

The present review discusses the recent repurposing of drugs for COVID-19 treatment.

RESULTS

Several compounds, including remdesivir, lopinavir, ritonavir, interferon-β, ribavirin, chloroquine/ hydroxychloroquine, azithromycin, tocilizumab, and ivermectin, have emerged as promising alternatives. They block the virus from entering host cells, prevent viral replication, and attenuate exacerbation of the host's immune response.

CONCLUSION

Although some evidence indicates the positive actions of different classes of compounds for the treatment of COVID-19, few clinical assays have been established to definitively demonstrate their therapeutic value in humans. Multicenter clinical studies are urgently needed to validate and standardize therapeutic regimens that involve these agents. Although science has not yet presented us with a specific drug against COVID-19, the repurposing of drugs appears to be promising in our fight against this devastating disease.

A Randomized Crossover Intervention Study on the Effect a Standardized Maté Extract (Ilex paraguariensis A. St.-Hil.) in Men Predisposed to Cardiovascular Risk

(1) Background: Due to its richness in chlorogenic acids (CGAs), Maté (Ilex paraguariensis A. St.-Hil.) could be of interest in the prevention of cardiometabolic diseases, however clinical evidence are lacking. This trial aimed to evaluate the impact of maté CGAs, consumed in a daily dose achievable through traditional maté beverages, on parameters related to cardiometabolic risk. (2) Design: Thirty-four male volunteers aged 45-65 years and with at most one criteria of metabolic syndrome, were recruited for a randomized, double-blind, placebo-controlled, and crossover study. The volunteers were assigned to consume an encapsulated dry maté extract for four-weeks, providing 580 mg of caffeoyl quinic acid derivatives (CQAs) daily, or a placebo, with a two weeks washout between intervention periods. Anthropometric variables, blood pressure, plasma glucose, lipids, endothelial, and inflammatory biomarkers were measured in overnight-fasted subjects and after a glucose load. (3) Results: We found no significant effects of treatment on these parameters and the response to the glucose load was also similar between the two interventions. However, a significant decrease in fasting glucose was observed between day 0 and day 28 for the maté group only (-0.57 ± 0.11 mmol/L, p < 0.0002). In subjects with an intermediate to high Framingham risk score, consumption of maté extract induced a 10% increase of high-density lipoprotein (HDL)-c from baseline. In a subgroup representative of the study population, significant decreases in the C-reactive protein (CRP) (-50%) and interleukin-6 (IL-6) (-19%) levels were observed. (4) Conclusions: These clinical observations suggest that maté, naturally rich in CGAs, could improve some cardiometabolic markers in subjects with a higher predisposition to metabolic syndrome, even if that remains to be confirmed in new trials specifically targeting this population.

MicroRNA-30 and 145 as targets for the treatment of cardiovascular diseases: therapeutic feasibility and challenges

Cardiovascular diseases (CVDs) are a group of non-communicable disorders of the heart and blood vessels. Although lifestyle changes as well as pharmacological treatments and surgical interventions are available in many countries, CVDs are still considered the number one cause of mortality worldwide. Hence, considering that most CVDs are caused by genetic and environmental imbalances, micro-RNAs (miRNAs or miRs) appear as a plausible therapeutic option for CVDs as they are able to regulate a wide number of genes due to multiple target sites in different genes. Since miRNA-30 and -145 have been shown to play critical roles in the cardiovascular system, acting as important regulators of many functions and biological processes, this review focuses on summarizing recent findings on their involvement in CVDs, mainly as targets for therapeutic intervention. Therefore, the biology, mechanisms of action and data on what has been discovered so far regarding miRNA-30 and 145 as therapeutic targets for CVDs are presented.

Ethnomedicinal Plants Used for the Treatment of Cardiovascular Diseases by Healers in the Southwestern State of Paraná, Brazil, and Their Validation Based on Scientific Pharmacological Data

Cardiovascular diseases are responsible for high morbidity and mortality rates worldwide. Among treatment options, medicinal plants are frequently used, especially in developing countries, such as Brazil. Despite social development that has been observed in the last decades, the use of medicinal plants is still driven by popular knowledge, especially by healers. The present study sought to identify medicinal species that are used for the treatment of cardiovascular diseases by healers in the microregion of Francisco Beltrão, Paraná, Brazil. The snowball technique was used to select informants, and data were collected through interviews. The research was performed in two stages: (1) a structured interview and (2) the collection and botanical identification of the species that were mentioned by the healers. Medicinal plants were classified into the following categories of cardiovascular agents: hypotensive and antihypertensive agents, lipid-lowering agents, diuretic agents, and cardiotonic agents. To analyze the data, the frequency was determined, Spearman correlations were calculated, and the informant consensus factor (ICF) and use value were obtained. Some characteristics, such as female gender and old age, were associated with knowledge about medicinal plants. Overall, 77 different species and 149 medicinal uses were cited by the healers. With regard to categories of use, the highest number of species was found among lipid-lowering plants, and the highest ICF was found for species that are used as cardiotonics. Moreover, a literature review indicated that among the cited species, several still lack studies that have proven their effects on the cardiovascular system. The traditional use of medicinal plants for the treatment of cardiovascular diseases is broad in the study regions. The present results are important for clarifying popular knowledge in this region and providing a framework for selecting species with potential for the development of new pharmacological studies.

Cuphea calophylla var. mesostemon (Koehne) S.A. Graham: A Whole-Ethnopharmacological Investigation

Several species of Cuphea are used medicinally and are reported to have cardioprotective, diuretic, and antihypertensive properties. In Brazil, Cuphea species are collectively called "sete-sangrias" due to their similar appearances and are also used interchangeably for the same therapeutic purposes. So the aim of the study was to characterize morphoanatomy of leaves and stems, evaluate the safety, and investigate the diuretic, hypotensive, vasodilatory, and antioxidant properties of ethanol-soluble fraction of Cuphea calophylla var. mesostemon (Koehne) S.A. Graham. Initially, the morphoanatomical characterization of the leaves and stems of C. calophylla var. mesostemon was performed. For the pharmacological evaluation, the ethanol-soluble fraction from Cuphea calophylla (ESCC) was obtained and chemically characterized by high-performance liquid chromatography coupled with a diode array detector and tandem mass spectrometry techniques. Then, acute toxicity, diuretic, hypotensive, antioxidant, and vasodilatory effects were evaluated in Wistar rats. The main chemical compounds identified from ESCC were gallic acid derivatives, ellagitannins, and flavonoids. ESCC showed no acute toxic effect. ESCC showed no acute toxic effect and the estimated median lethal dose (LD₅₀) was above 2000 mg/kg. ESCC treatment (30, 100, and 300 mg/kg) did not present any significant acute diuretic or hypotensive effects. However, an important reduction in the elimination of electrolytes was observed after the acute administration, and a significant increase in renal sodium elimination was observed after 7 days of treatment. In the cardiac tissue, the groups treated with ESCC presented significant increase in superoxide dismutase activity.

From general toxicology to DNA disruption: A safety assessment of Plinia cauliflora (Mart.) Kausel

ETHNOPHARMACOLOGICAL RELEVANCE

Plinia cauliflora (Mart.) Kausel (Myrtaceae) is popularly known as "jaboticaba" or "jaboticaba". The fruit is appreciated for both fresh consumption and the manufacture of jelly, juice, ice cream, fermented beverages, and liqueurs. The more widespread traditional use of the plant involves the treatment of diarrhea, which utilizes all parts of the plant, including the fruit peels.

AIM OF THE STUDY

We sought to elucidate possible risks of the administration of an ethanol-soluble fraction that was obtained from an infusion of P. cauliflora fruit peels (SEIPC). We performed a series of experiments to evaluate possible toxicity, in which we administered SEIPC orally both acutely and repeatedly for 28 days. We also evaluated possible endocrine-disruptive and genotoxic effects in eukaryotic cells. The possible mutagenic activity of SEIPC was evaluated using reverse mutation (Ames) assays.

MATERIALS AND METHODS

SEIPC was produced and chemically characterized by LC-DAD-MS. Acute toxicity and behavioral and physiological alterations were evaluated in the modified Irwin test. Respiratory rate, arterial blood gas, electrocardiography, respiratory rate, heart rate, and blood pressure were evaluated, and hematological, biochemical, and histopathological analyses were performed after 28 days of oral treatment. The comet assay, mammalian erythrocyte micronucleus test, uterotrophic test, Hershberger bioassay, and AMES test were performed using appropriate protocols.

RESULTS

From SEIPC, ellagic acid and derivatives, flavonols and anthocyanidins, as well as citric acid and gallic acid, were annotated by LC-DAD-MS. We did not observed any significant toxic effects after acute or prolonged SEIPC treatment. No endocrine-disruptive or mutagenic effects were observed.

CONCLUSIONS

The present study found that SEIPC did not cause any significant alterations of various corporeal systems, including cardiac electrical activity, body temperature, respiratory rate, and arterial pressure. No alterations of biochemical, hematological, or blood gas parameters were observed. SEIPC did not cause any perturbations of the endocrine system or mutagenic, cytotoxic, or genotoxic effects. These findings substantiate the safe clinical use of P. cauliflora.

Nitric oxide and Ca2+-activated high-conductance K+ channels mediate nothofagin-induced endothelium-dependent vasodilation in the perfused rat kidney

Nothofagin is a natural 3'-C-β-D-glucoside of the polyphenol phloretin that is mainly found in Aspalathus linearis, Nothofagus fusca, and Leandra dasytricha. In recent years, nothofagin has been described as a potential therapeutic agent for renal disorders, but the mechanisms that are involved in its renoprotective effects remain unclear. In the present study, perfused rat kidneys were used to test the hypothesis that nothofagin causes the direct relaxation of renal arteries. The molecular mechanisms that underlie these vascular effects were also investigated. The left kidney from Wistar rats was coupled in a perfusion system and continuously perfused with physiological saline solution (PSS). Initially, preparations with and without the endothelium were contracted with phenylephrine and received injections of 1-300 nmol nothofagin. The preparations were then perfused with PSS that contained phenylephrine plus KCl, indomethacin, l-NAME, tetraethylammonium, glibenclamide, 4-aminopyridine, iberiotoxin, charybdotoxin, and apamin. After 15 min under perfusion, nothofagin was injected again. In preparations with an intact endothelium, nothofagin dose-dependently reduced perfusion pressure. Endothelium removal or the inhibition of nitric oxide synthase by l-NAME prevented the vasodilatory effect of nothofagin at all doses tested. Perfusion with PSS that contained KCl or tetraethylammonium chloride also abolished the vasodilatory effect of nothofagin. Treatment with glibenclamide, 4-aminopyridine, and apamin did not affect the vasodilatory effect of nothofagin. Iberiotoxin (selective Ca²⁺-activated high-conductance K⁺ channel [KCa1.1] blocker) and charybdotoxin (selective KCa1.1 and Ca²⁺-activated intermediate-conductance K⁺ channel [KCa3.1] blocker) application blocked the vasodilatory effect of nothofagin at all doses tested, pointing to a predominant role for KCa1.1 in the action of nothofagin. However, these data cannot exclude a potential contribution of endothelial KCa3.1 channel in the nothofagin-induced vasodilation. Overall, our findings indicate that nothofagin induces vasodilation in renal arteries, an effect that is mediated by Ca²⁺ -activated high-conductance K⁺ channels opening and endothelial nitric oxide production.

Promising therapeutic use of Baccharis trimera (less.) DC. as a natural hepatoprotective agent against hepatic lesions that are caused by multiple risk factors

ETHNOPHARMACOLOGICAL RELEVANCE

Baccharis trimera (Less.) DC is a perennial subshrub, popularly known as "carqueja," that belongs to the Asteraceae family. Ethnobotanical studies indicate that this species is used for the treatment of diabetes and digestive and liver diseases. However, studies that sought to validate its popular use were conducted using ethanolic extracts of the plant, which does not reflect the ethnomedicinal use of this species in humans.

AIM OF THE STUDY

Non-alcoholic fatty liver disease (NAFLD) is characterized by triglyceride accumulation in the liver that can progress to cirrhosis and hepatocellular carcinoma. Because of the severity of this disease, less toxic and more effective therapeutic agents need to be developed. B. trimera may be a promising therapeutic alternative, but its activity against multiple risk factors for liver disease (e.g., smoking, dyslipidemia, and diabetes mellitus) has not been studied. The present study investigated the effects of an ethnomedicinal form of a B. trimera preparation in a rat model of NAFLD that is associated with multiple risk factors.

MATERIAL AND METHODS

Phytochemical analysis of the ethanolic soluble fraction of B. trimera extract was performed using ultra-performance liquid chromatography coupled to high-resolution mass spectrometry. Streptozotocin was used to induce diabetes in male Wistar rats. The rats received a 0.5% cholesterol-enriched diet and were exposed to cigarette smoke (9 cigarettes/day, 5 days/week, for 4 weeks). In the last 2 weeks, the animals were orally treated with vehicle (negative control group), B. trimera extract (30, 100, and 300 mg/kg), or insulin + simvastatin. One group of rats that was not exposed to these risk factors was also evaluated. Blood was collected for glucose, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) analysis. The liver and feces were collected for lipid quantification. The liver was additionally processed for histopathological analysis.

RESULTS

The model successfully induced NAFLD and increased levels of glucose, AST, and ALT in the negative control group. Treatment with the B. trimera extract (30 and 100 mg/kg) and insulin + simvastatin decreased hepatic and fecal lipids. In contrast to insulin + simvastatin treatment, all three doses of B. trimera effectively reduced AST and ALT levels.

CONCLUSION

B. trimera may be promising as a hepatoprotective agent against hepatic lesions that are caused by multiple risk factors.

Role of the NO/cGMP pathway and renin-angiotensin system in the hypotensive and diuretic effects of aqueous soluble fraction from Crataegus songarica K. Koch

ETHNO-PHARMACOLOGICAL RELEVANCE

Fruits of Crataegus songarica K. Koch. (Rosaceae) are commonly used in folk medicine for their diuretic properties to treat hypertension and congestive heart failure. To date, no scientific data has been published to support the diuretic potential.

AIM OF THE STUDY

The purpose of this study was to evaluate efficacy and mechanism underlying the hypotensive and diuretic action of C. songarica in normotensive rats and to determine the constituents from the extracts by LC-DAD-MS.

MATERIALS AND METHODS

Firstly, phytochemical profiling and antioxidant potential of C. songarica extracts was determined. Then, to evaluate changes in blood pressure, different groups of anesthetized normotensive rats were intravenously treated with crude extract (CS-Cr, 10-80 mg/kg), aqueous soluble (AS-CS, 0.1-20 mg/kg), and n-butanol soluble fractions of C. songarica (BS-CS, 1-80 mg/kg). The diuretic effects of CS-Cr (100-500 mg/kg, p.o), AS-CS (100-300 mg/kg, p.o) and BS-CS (100-300 mg/kg, p.o) were evaluated in comparison with hydrochlorothiazide (HCTZ, 10 mg/kg, p.o). The urinary volume, sodium, potassium and pH were estimated in the sample collected for 6 h from saline-loaded rats. Using pharmacological antagonists or inhibitors, we determine the involvement of acetylcholine, prostaglandins, and nitric oxide in C. songarica induced hypotensive and diuresis action. In addition, the activities of angiotensin converting enzyme, erythrocytary carbonic anhydrase and renal Na+/K+/ATPase were evaluated in vitro.

RESULTS

From the LC-DAD-MS analyses, thirty-nine compounds were detected, showing a complex chemical profile and an expressive antioxidant activity "in vitro". Acute treatment with CS-Cr, AS-CS, and BS-CS exhibited significant hypotensive and diuretic potential in normotensive rats. However, AS-CS produced most potent and significant dose-dependent hypotension in normotensive rats, and also produced highly significant diuretic and saluretic effects. Despite the changes in urinary excretion of electrolytes, the plasmatic levels of sodium and potassium were not changed. Previous treatment with atropine and L-NAME significantly reduced the hypotensive and diuretic action of AS-CS in normotensive rats. Moreover, the 7-day treatment with AS-CS also resulted in significant ACE inhibitory activity.

CONCLUSION

This research supports and extends the ethnomedicinal use of C. songarica as diuretic and hypotensive agent. The results showed that AS-CS from C. songarica could present compounds responsible for hypotensive and diuretic activities with no signs of toxicity, and these effects could involve nitric oxide pathway activated by muscarinic receptors or/and inhibition of angiotensin converting enzyme.

Ameliorative Effects and Cellular Aspects of Phytoconstituents in Atherosclerosis

Atherosclerosis is a cardiovascular disease that involves vessels through the development of fatty streaks and plaques. Plant-based compounds can help treat or prevent atherosclerosis by affecting various factors that are involved in the disease. The present review discusses our current knowledge of the major cellular and molecular mechanisms of phytotherapeutics for the treatment of atherosclerosis. Numerous studies have evaluated the antiatherosclerotic activity of phytoconstituents to provide preliminary evidence of efficacy, but only a few studies have delineated the underlying molecular mechanisms. Plant-derived phytotherapeutics primarily targets abnormal levels of lipoproteins, endothelial dysfunction, smooth muscle cell migration, foam cell development, and atheromatous plaque formation. Nonetheless, the principal mechanisms that are responsible for their therapeutic actions remain unclear. Further pharmacological studies are needed to elucidate the underlying molecular mechanisms of the antiatherosclerotic response to these phytoconstituents.

Recent Advances in the Knowledge of Naturally-derived Bioactive Compounds as Modulating Agents of the Renin-angiotensin-aldosterone System: Therapeutic Benefits in Cardiovascular Diseases

BACKGROUND

One of the biggest challenges to public health worldwide is to reduce the number of events and deaths related to the cardiovascular diseases. Numerous approaches have been applied to reach this goal, and drug treatment intervention has been indispensable along with an effective strategy for reducing both cardiovascular morbidity and mortality. Renin-angiotensin-aldosterone system (RAAS) blockade is currently one of the most important targets of cardiovascular drug therapy. Many studies have proven the valuable properties of naturally-derived bioactive compounds to treat cardiovascular diseases.

METHODS

The goal of this review, therefore, is to discuss the recent developments related to medicinal properties about natural compounds as modulating agents of the RAAS, which have made them an attractive alternative to be available to supplement the current therapy options.

RESULTS

Data has shown that bioactive compounds isolated from several natural products act either by inhibiting the angiotensin-converting enzyme or directly by modulating the AT1 receptors of angiotensin II, which consequently changes the entire classical axis of this system.

CONCLUSION

While there are a few evidence about the positive actions of different classes of secondary metabolites for the treatment of cardiovascular and renal diseases, data is scarce about the clinical assays established to demonstrate their value in humans.

Plinia cauliflora (Mart.) Kausel: A comprehensive ethnopharmacological review of a genuinely Brazilian species

ETHNOPHARMACOLOGICAL RELEVANCE

Plinia cauliflora (Mart.) Kausel is widespread in alluvial plains and open forests in Brazil, Argentina, and Paraguay. The fruits of P. cauliflora are used as food, and almost all parts of this species have long been used as a traditional Brazilian medicine for the treatment of skin irritations, flu, diarrhea, labyrinthitis, genito-urinary problems, and asthma.

THE AIM OF THE REVIEW

This review provides comprehensive and up-to-date information on P. cauliflora with regard to its ethnopharmacological uses, constituents, biological activities, and toxicology, all of which are useful for future research and the development of new drugs.

MATERIALS AND METHODS

The information and data on P. cauliflora were collected from ethnobotanical textbooks and scientific databases, such as PubMed, Scopus, EBSCO, Science Direct, Google, and Google Scholar.

RESULTS

The main chemical constituents in P. cauliflora preparations were depsides, flavonoids, and hydrolysable tannins. The main medicinal use of the species in Brazil is for the treatment of diarrhea. Although antimicrobial potential of this species has been demonstrated, data on gastrointestinal motility are still incipient and need further investigation. Studies that indicate the efficacy of its traditional use for sore throat, pelvic hemorrhage, uterine wounds, vaginal discharge, and flu are nonexistent. The scientific literature does not describe any toxic effects of its popular use. However, the available data do not allow us to conclude that the ethnomedicinal use of this species is safe, with a lack of well-designed preclinical tests and randomized clinical trials.

CONCLUSION

This review summarizes research on the traditional use, phytochemistry, biological activities, and toxicology of P. cauliflora. Although P. cauliflora possesses significant biological activities, much of its ethnomedicinal use has not been scientifically evaluated. Well-designed pharmacological and toxicological assays and randomized clinical trials are still needed to validate its ethnopharmacological use as an herbal medicine.

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.