Myrciaria caulifloraPeel Flour Had a Hypolipidemic Effect in Rats Fed a Moderately High-Fat Diet

Jaboticaba peel improves postprandial glucose and inflammation: A randomized controlled trial in adults with metabolic syndrome

The modulation of glucose metabolism through dietary sources has been recognized as 1 of the most sustainable approaches for preventing of cardiometabolic diseases. Although fibers and phenolic compounds derived from jaboticaba (Plinia jaboticaba) peel have demonstrated improvements in metabolic pathways in preclinical models, their beneficial effects in clinical trials remain to be fully determined. This study aimed to assess the impact of jaboticaba peel (JP) powder supplementation on glucose metabolism compared with a placebo in individuals with metabolic syndrome (MetS). A single-blind, parallel, randomized, placebo-controlled trial involving 49 individuals with MetS was conducted. Participants were assigned to receive either a JP supplement (15 g/day) or a matched placebo. Anthropometry measurements, body composition, blood pressure, metabolic and inflammatory parameters, and a mixed-meal tolerance test were assessed at weeks 0 and 5. Daily intake of JP improved the area under the curve of glucose (P = .025) and the interleukin-6 (IL-6) (P = .045). No significant time × treatment effects were observed for blood pressure, body weight, body composition, lipid metabolism, glucagon-like peptide-1, inflammatory cytokines (tumor necrosis factor-α, IL-1β), C-reactive protein, and insulin sensitivity and resistance indexes. JP supplementation may be a promising approach for managing MetS disorders, potentially by reducing the area under the curve for glucose and the proinflammatory cytokine IL-6. This research is registered at the Brazilian Registry of Clinical Trials (RBR-8wwq9t).

The Role of By-Products of Fruit and Vegetable Processing for the Dietary Treatment of Cardiovascular Risk Factors: A Narrative Review

Polyphenols-rich food has been utilized to induce a positive effect on human health. Considering that fruit and vegetable by-products (seeds, pomace, and peels) are sources of polyphenols, previous studies have investigated the effect of dietary supplementation with food by-products on cardiometabolic disorders, such as high fasting blood glucose, dyslipidemia, and obesity. Endothelial dysfunction has also been considered a cardiometabolic parameter, given that it precedes cardiovascular disease. However, there is a scarcity of narrative reviews reporting the effect of food by-product supplementation on cardiometabolic disorders in animal and human clinical trials. In this sense, the present narrative review aims to investigate the impact of fruit and vegetable by-product supplementation on cardiometabolic disorders in humans and animals, exploring the possible mechanisms whenever possible. Research articles were retrieved based on a search of the following databases: PubMed, ScienceDirect, and Google Scholar using the following keywords and synonyms combined: (“fruit by-products” or “food waste” or “pomace” or “bagasse” or “seeds” or “waste products”) AND (“heart disease risk factors” or “endothelial dysfunction” or “atherosclerosis”). It was shown that fruit and vegetable by-products could efficiently improve cardiometabolic disorders in patients with chronic diseases, including hypertension, type II diabetes mellitus, and dyslipidemia. Such effects can be induced by the polyphenols present in food by-products. In conclusion, food by-product supplementation has a positive effect on cardiometabolic disorders. However, further studies investigating the effect of food by-products on cardiometabolic disorders in humans are still necessary so that solid conclusions can be drawn.

An Integrative Review on the Main Flavonoids Found in Some Species of the Myrtaceae Family: Phytochemical Characterization, Health Benefits and Development of Products

This integrative review aims to identify the main flavonoids present in some species of the Myrtaceae family. Studies published between 2016 and 2022 were selected, specifically those which were fully available and written in Portuguese, English, or Spanish, and which were related to the fruits araçá (Psidium cattleianum), cambuí (Myrciaria floribunda), gabiroba (Campomanesia xanthocarpa), jabuticaba (Plinia cauliflora), and jambolan (Syzygium cumini). Scientific studies were gathered and selected in Google Scholar, Scielo, and Science Direct indexed databases, out of which 14 were about araçá, 7 concerned cambuí, 4 were about gabiroba, 29 were related to jabuticaba, and 33 concerned jambolan, when we observed the pre-established inclusion criteria. Results showed that the anthocyanins, such as cyanidin, petunidin, malvidin, and delphinidin, were the mostly identified class of flavonoids in plants of the Myrtaceae family, mainly relating to the purple/reddish color of the evaluated fruits. Other compounds, such as catechin, epicatechin, quercetin, and rutin were also identified in different constituent fractions, such as leaves, peel, pulp, seeds, and in developed products, such as jams, desserts, wines, teas, and other beverages. It is also worth noting the positive health effects verified in these studies, such as anti-inflammatory qualities for jambolan, antidiabetic qualities for gabiroba, antioxidant qualities for araçá, and cardioprotective actions for jabuticaba, which are related to the presence of these phytochemicals. Therefore, it is possible to point out that flavonoids are important compounds in the chemical constitution of the studied plants of the Myrtaceae family, with promising potential in the development of new products by the food, chemical, and pharmaceutical industries due to their bioactive properties.

Pharmacological investigation of antioxidant and anti-inflammatory activities of leaves and branches extracts from Plinia cauliflora (Jaboticaba)

ETHNOPHARMACOLOGICAL RELEVANCE

Among all native Brazilian plant species, Plinia cauliflora (DC.) Kausel (Jaboticaba), is well known for producing "superfruits", due to their high phenolic content and antioxidant property. The fruit has astringent characteristics, and it is popularly known for the treatment of diarrhea, rash, and intestinal inflammation. However, there are only a few studies on the use of leaves and branches of this species in the literature, mainly to treat oxidative stress and inflammation.

AIM OF THE STUDY

The present study aimed to investigate the antioxidant and anti-inflammatory potential of leaves and branches extracts from P. cauliflora.

MATERIAL AND METHODS

The phytochemical analysis of P. cauliflora extracts was performed by the total phenolic, flavonoid, and tannin dosage method. Moreover, the compounds were identified by HPLC-MS-Q-TOF. Antioxidant capacity was determined by DPPH, β-carotene/linoleic acid system, MDA formation, and phosphomolybdenum assays. In vitro and in vivo anti-inflammatory activities of P. cauliflora were evaluated by the reduction of nitric oxide in the J774A.1 cell line and inhibition of ear edema in mice, respectively.

RESULTS

The ethanolic extract of the leaves exhibited greater flavonoid content whereas the ethanolic extract of the branches showed higher tannins content. Twenty-two and seventeen compounds were identified by HPLC-MS-Q-TOF in the leaves and branches, respectively, being tellimagrandin I, castalagin, and valoneic acid dilactone reported for the first time in P. cauliflora. The antioxidant potential of extracts was confirmed through different oxidation pathways from oxidizing radicals, which might be related to the presence of phenolic compounds. For the anti-inflammatory assay, the leaves and branches extracts showed promising results, with a reduction of nitric oxide ear edema inhibition around 95% and 80%, respectively.

CONCLUSIONS

Herein, the great biological potential of leaves and branches extracts from P. cauliflora was highlighted. These parts of the plant are underused and poorly reported in the literature, especially for the antioxidant and anti-inflammatory activities.

Effects of liquid extract from Plinia cauliflora fruits residues on Chinese hamsters biochemical parameters

Plinia cauliflora (Mart.) Kausel, popularly known as jabuticaba, is rich in polyphenols. Phenolic compounds exhibit several biological properties, which reflect on biomarkers such as biochemical parameters. In the present study, we evaluated the plasmatic levels of glucose, total cholesterol, HDL-cholesterol, triglycerides, and uric acid of Chinese hamsters fed for 45 days with a regular diet or cholesterol-enriched diet supplemented with a liquid extract obtained from P. cauliflora fruits residues standardized in ellagic acid and total phenolic compounds. The results showed that the concentrated extract obtained from jabuticaba residues increased the glycemia of animals fed with a regular diet and reduced the plasmatic uric acid levels of animals fed with a cholesterol-enriched diet. Since hyperuricemia is considered to be a significant risk factor of metabolic disorders and the principal pathological basis of gout, the liquid extract from P. cauliflora fruits residues would be a promising candidate as a novel hypouricaemic agent for further investigation.

Jaboticaba berry: A comprehensive review on its polyphenol composition, health effects, metabolism, and the development of food products

Jaboticaba, a popular Brazilian berry, has been studied due to its relevant polyphenol composition, health benefits and potential use for the development of derived food products. Considering that around 200 articles have been published in recent years, this review aims to provide comprehensive and updated information, as well as a critical discussion on: (i) jaboticaba polyphenolic composition and extraction methods for their accurate determination; (ii) jaboticaba polyphenol's metabolism; (iii) biological effects of the fruit and the relationship with its polyphenols and their metabolites; (iv) challenges in the development of jaboticaba derived products. The determination of jaboticaba polyphenols should employ hydrolysis procedures during extraction, followed by liquid chromatographic analysis. Jaboticaba polyphenols, mainly anthocyanins and ellagitannins, are extensively metabolized, and their metabolites are probably the most important contributors to the relevant health effects associated with the fruit, such as antioxidant, anti-inflammatory, antidiabetic, hepatoprotective and hypolipidemic. Most of the technological processing of jaboticaba fruit and its residues is related to their application as a colorant, antioxidant, antimicrobial and source of polyphenols. The scientific literature still lacks studies on the metabolism and bioactivity of polyphenols from jaboticaba in humans, as well as the effect of technological processes on these issues.

Rheological and technological characterization of red rice modified starch and jaboticaba peel powder mixtures

Properties of modified starch and its interaction with functional raw materials are of great interest to the food industry. Thus, this study aimed to evaluate the rheological and technological characterization of starches modified by the action of the enzymes α-amylase and amyloglucosidase and their mixtures with jaboticaba peel powder. The parameters of firmness, gumminess, and final viscosity of starches paste increased, and the tendency to setback was reduced with the addition of jaboticaba peel powder. Starches and mixtures presented shear-thinning behavior. The addition of jaboticaba peel powder to starches increased water, oil, and milk absorption capacity, while syneresis remained stable over the storage period. The addition of jaboticaba peel powder had a positive effect on native and modified starches' rheological and technological properties, qualifying it as an alternative for developing new functional food products.

Jabuticaba peel extract modulates adipocyte and osteoblast differentiation of MSCs from healthy and osteoporotic rats

INTRODUCTION

The jabuticaba peel extract (JPE) contains bioactive compounds that regulate fat metabolism. Because the negative correlation between fat accumulation and bone formation in bone marrow, we hypothesized that JPE inhibits adipocyte as well as favors osteoblast differentiation of mesenchymal stromal cells (MSCs) under healthy and osteoporotic conditions, a disease that display an imbalance between adipocyte and osteoblast differentiation resulting in reduced bone mass.

MATERIAL AND METHODS

To test these hypotheses, bone marrow MSCs were harvested from healthy and osteoporotic rats and cultured in adipogenic and osteogenic media with three concentrations of JPE, 0.25, 5 and 10 µg/ml, and vehicle (control). After selecting the most efficient concentrations of JPE, we used them to evaluate adipocyte and osteoblast differentiation of MSCs from both sources.

RESULTS

We observed that, in general, JPE inhibited adipocyte differentiation of MSCs with more pronounced effects in cells from healthy than osteoporotic rats. In addition, JPE increased osteoblast differentiation, exhibiting a slightly higher osteogenic potential on MSCs from osteoporotic compared to healthy condition.

CONCLUSION

Our results demonstrated that JPE drives MSCs to inhibit adipocyte differentiation and toward osteoblast differentiation under healthy and osteoporotic conditions. These findings pave the way for further translational studies to investigate the therapeutic possibilities of JPE in both prevention and treatment of osteoporosis.

Jaboticaba (Myrciaria cauliflora) Peel Supplementation Prevents Hepatic Steatosis Through Hypolipidemic Effects and Cholesterol Metabolism Modulation in Diet-Induced NAFLD Rat Model

Jaboticaba (Myrciaria cauliflora), a Brazilian fruit, is a good source of dietary fiber and phenolic compounds, which are concentrated mainly in the peel. These compounds have been considered promising in prevention and treatment of hypercholesterolemia and hepatic steatosis. In this study, we investigated the effects of 4% jaboticaba peel powder (JPP) supplementation on cholesterol metabolism and hepatic steatosis in livers of rats fed a high-fat (HF) diet. The rats were fed a standard AIN-93M (control) diet or an HF diet containing 32% lard and 1% cholesterol, both with and without 4% JPP. The M. cauliflora peel composition revealed a low-lipid high-fiber content and phenolic compounds. The phenolic compounds in JPP, tentatively identified by high-performance liquid chromatography and mass spectrometry (HPLC-MS/MS) analysis, were confirmed to contain phenolic acids, flavonoids, and anthocyanins. Moreover, JPP presented significant antioxidant activity in vitro and was not cytotoxic to HepG2 cells, as determined by the lactate dehydrogenase (LDH) assay. After 6 weeks of treatment, our results showed that JPP supplementation increased lipid excretion in feces, reduced serum levels of total cholesterol and nonhigh-density lipoprotein cholesterol, decreased serum aspartate aminotransferase (AST) activity, and attenuated hepatic steatosis severity in rats fed the HF diet. Furthermore, JPP treatment downregulated expression of ACAT-1, LXR-α, CYP7A1, and ABCG5 genes. Therefore, jaboticaba peel may represent a viable dietary strategy to prevent nonalcoholic fatty liver disease as the JPP treatment alleviated hepatic steatosis through improvement of serum lipid profiles and modulation of mRNA expression of genes involved in cholesterol metabolism.

Time-restricted feeding in dark phase of circadian cycle and/or westernized diet cause mixed hyperlipidemia in rats

Introduction

Background: the dietary pattern that characterizes western diet is strongly associated with metabolic diseases and excess weight, as well as chronic illnesses. Misaligned feeding schedules can lead to or aggravate the development of such conditions. Aim: this study evaluated the influence of dietary composition and/or time-restricted feeding on the anthropometric and biochemical profile of adult rats. Methods: forty male rats, at 60 days of life, were divided into the following groups: Control (C), Restricted Control (RC), Westernized (W), and Restricted Westernized (RW). Results: westernized groups, in spite of a low energy intake (C = 5399 ± 401.2 kcal; RC = 4279.0 ± 476.2 kcal; W = 4302 ± 619.8 kcal; RW = 4081.0 ± 404.4 kcal, p < 0.001), had a higher body weight (C = 404.6 ± 39.1 g; RC = 335.1 ± 36.5 g; W = 488.9 ± 51.2 g; RW = 438.8 ± 36.5 g, p < 0.001) as compared to their paired controls (RC and C) - around 30 % and 20 % more for RW and W, respectively. The westernized diet caused glucose intolerance and mixed hyperlipidemia, characterized by higher concentrations of cholesterol (C = 40.8 ± 7.4 mg/dL; RC = 76.7 ± 10.8 mg/dL; W = 61.3 ± 20.2 mg/dL; RW = 42.2 ± 8.2 mg/dL), LDLc (C = 17.4 ± 7.5 mg/dL; RC = 38.8 ± 7.2 mg/dL ; W = 45.3 ± 15.8 mg/dL; RW = 11.0 ± 5.8 mg/dL), and triacylglycerol (C = 45.2 ± 15.0 mg/dL; RC = 73.2 ± 21.5 mg/dL ; W = 83.6 ± 23.4 mg/dL; RW = 57.5 ± 13.6 mg/dL) in the serum (p < 0.05). Conclusion: the effect of time-restricted feeding on body weight was strongly dependent on diet composition. The glucose tolerance test showed an influence of the circadian cycle phase. Mixed hyperlipidemia varied according to the presence of westernized diet and/or time-restricted food.

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.

Campomanesia sp. flour attenuates non-alcoholic fatty liver disease on rats fed with a hypercaloric diet

Non-alcoholic fatty liver disease (NAFLD) is a metabolic disorder caused by excess consumption of hypercaloric foods. Guavira (Campomanesia sp.) pulp has broad technological applicability, yet the peel and seeds are considered industrial residue. The objective of this unprecedented study was to evaluate the effects of the flour from guavira's industrial residue (GF) consumption in rats fed with hypercaloric diet (HD). During 65 days, 50 rats were separated into a control group: 1%, 2%, 4% and 8% HD with GF complementation in the diet. The GF chemical composition, phenolic compounds, antioxidant capacity, serum biochemical parameters (glucose, cholesterol, HDL, non-HDL, triglycerides, AST, ALT, and oral glucose tolerance test), fat liver content, and hepatic histomorphology had been characterized. GF is mainly composed of fibres, with phenolic content of 7,391.09 mg AGE/100 g GF and relevant antioxidant capacity (IC50 2.22 and ORAC 155.68 μmol/TE g^-1 ). Serum biochemical analysis did not differ statistically (except ALT reduction, p < .05). Fat liver content was smaller on HD2%GF (p < .0001). The control group and 1% GF showed greater diffuse microvesicular steatosis compared to the other groups when using hepatic morphological analysis (p < .05). GF consumption attenuated NAFLD caused by a hypercaloric diet, and this effect may be related to the fibre content and bioactive compounds in GF.

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.

Cardioprotective effects of Plinia cauliflora (Mart.) Kausel in a rabbit model of doxorubicin-induced heart failure

ETHNOPHARMACOLOGICAL RELEVANCE

In Brazil, the fruit of a native species that is popularly known as "jabuticaba" (Plinia cauliflora [Mart.] Kausel) is widely consumed fresh or used for the production of liqueur, juice, and jelly. In Brazilian folk medicine, this species is used to treat asthma, throat inflammation, and gastrointestinal and cardiovascular disturbances. However, no previous studies have reported its cardioprotective effects.

AIM

To evaluate the possible cardioprotective effects of a hydroethanolic extract of Plinia cauliflora (EEPC) in female rabbits in a model of doxorubicin-induced heart failure.

MATERIAL AND METHODS

EEPC was obtained and fractionated by solid phase extraction, and its constituents were determined by liquid chromatography coupled to diode array detector and mass spectrometry (LC-DAD-MS). Thirty female New Zealand rabbits received doxorubicin administration for 6 weeks to induce heart failure. EEPC was orally administered at doses of 75 and 150 mg/kg daily for 42 days. Enalapril (5 mg/kg) was used as a reference cardioprotective drug. At the end of the experimental period, blood pressure and heart rate were recorded. Serum parameters, including lipid profile, troponin, creatinine, nitrotyrosine, malondialdehyde, nitrite, and brain natriuretic peptide, were measured. The electrocardiographic profile and renal vascular reactivity were evaluated. Cardiac histopathology and ventricular morphometry were performed, and the tissue enzymatic antioxidant system was investigated.

RESULTS

A total of 37 compounds were detected in EEPC, including organic acids, phenolic acid derivatives, flavonoids, anthocyanins, and hydrolysable tannins (gallotannins and ellagitannins). EEPC treatment induced a cardiorenal protective response, prevented hemodynamic and functional alterations, and prevented ventricle remodeling. These effects were associated with the normalization of creatinine and brain natriuretic peptide levels and modulation of the tecidual antioxidant defense system.

CONCLUSION

The present study demonstrated that EEPC may prevent doxorubicin-induced heart failure by modulating the antioxidant defense system, reducing reactive oxygen species-induced damage, preventing alterations of hemodynamic and endothelial function, and preventing damage to the cardiac structure. EEPC, especially at the highest dose tested, may be considered a cardioprotective coadjuvant to prevent doxorubicin-induced cardiotoxicity.

Pharmacological safety of Plinia cauliflora (Mart.) Kausel in rabbits

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Fruit peels of Plinia cauliflora are widely used in Brazilian traditional medicine.

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No studies have proved the safety of its pharmacological effects.

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We assessed the safety pharmacology of P. cauliflora extract (EEPC) in rabbits.

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EEPC did not cause any significant changes in several physiological systems.

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These data provide important safety data for its clinical use.

Fruit peels of Plinia cauliflora (Mart.) Kausel are widely used in Brazilian traditional medicine, but no studies have proved the safety of its pharmacological effects on the respiratory, cardiovascular, and central nervous systems. The present study assessed the safety pharmacology of P. cauliflora in New Zealand rabbits. First, an ethanol extract (EEPC) was selected for the pharmacological experiments and chemical characterization. Then, different groups of rabbits were orally treated with EEPC (200 and 2000 mg/kg) or vehicle. Acute behavioral and physiological alterations in the modified Irwin test, respiratory rate, arterial blood gas, and various cardiovascular parameters (i.e., heart rate, blood pressure, and electrocardiography) were evaluated. The main secondary metabolites that were identified in EEPC were ellagic acid, gallic acid, O-deoxyhexosyl quercetin, and the anthocyanin O-hexosyl cyanidin. No significant behavioral or physiological changes were observed in any of the groups. None of the doses of EEPC affected respiratory rate or arterial blood gas, with no changes on blood pressure or electrocardiographic parameters. The present study showed that EEPC did not cause any significant changes in respiratory, cardiovascular, or central nervous system function. These data provide scientific evidence of the effects of this species and important safety data for its clinical use.

Jabuticaba-Induced Endothelium-Independent Vasodilating Effect on Isolated Arteries

Background:

Despite the important biological effects of jabuticaba, its actions on the cardiovascular system have not been clarified.

Objectives:

To determine the effects of jabuticaba hydroalcoholic extract (JHE) on vascular smooth muscle (VSM) of isolated arteries.

Methods:

Endothelium-denuded aortic rings of rats were mounted in isolated organ bath to record isometric tension. The relaxant effect of JHE and the influence of K+ channels and Ca2+ intra- and extracellular sources on JHE-stimulated response were assessed.

Results:

Arteries pre-contracted with phenylephrine showed concentration-dependent relaxation (0.380 to 1.92 mg/mL). Treatment with K+ channel blockers (tetraethyl-ammonium, glibenclamide, 4-aminopyridine) hindered relaxation due to JHE. In addition, phenylephrine-stimulated contraction was hindered by previous treatment with JHE. Inhibition of sarcoplasmic reticulum Ca2+ ATPase did not change relaxation due to JHE. In addition, JHE inhibited the contraction caused by Ca2+ influx stimulated by phenylephrine and KCl (75 mM).

Conclusion:

JHE induces endothelium-independent vasodilation. Activation of K+ channels and inhibition of Ca2+ influx through the membrane are involved in the JHE relaxant effect.

Fundamentos:

Embora a jabuticaba apresente importantes efeitos biológicos, suas ações sobre o sistema cardiovascular ainda não foram esclarecidas.

Objetivos:

Determinar os efeitos do extrato de jabuticaba (EHJ) sobre o músculo liso vascular (MLV) em artérias isoladas.

Métodos:

Aortas (sem endotélio) de ratos foram montadas em banho de órgãos isolados para registro de tensão isométrica. Foram verificados o efeito relaxante, a influência dos canais de K+ e das fontes de Ca2+ intra- e extracelular sob a resposta estimulada pelo EHJ.

Resultados:

Artérias pré-contraídas com fenilefrina apresentaram relaxamento concentração-dependente (0,380 a 1,92 mg/mL). O tratamento com bloqueadores de canais de K+ (tetraetilamônio, glibenclamida, 4-aminopiridina) prejudicaram o relaxamento pelo EHJ. A contração estimulada com fenilefrina também foi prejudicada pelo tratamento prévio com EHJ. A inibição da Ca2+ATPase do reticulo sarcoplasmático não alterou o relaxamento pelo EHJ. Além disso, o EHJ inibiu a contração causada pelo influxo de Ca2+ estimulado por fenilefrina e KCl (75 mM).

Conclusão:

O EHJ induz vasodilatação independente do endotélio. Ativação dos canais de K+ e inibição do influxo de Ca2+ através da membrana estão envolvidas no efeito relaxante do EHJ.

Vasorelaxant and Hypotensive Effects of Jaboticaba Fruit (Myrciaria cauliflora) Extract in Rats

This study's aim was to determine the effect of hydroalcoholic extract of M. cauliflora (HEMC) on vascular tension and blood pressure in rats. In our in vitro studies using precontracted isolated aortas from rats, HEMC and acetylcholine (positive control) induced relaxation only in vessels with endothelium. Pretreatment with L-NAME (NO synthase inhibitor) or ODQ (soluble guanylyl cyclase (sGC) inhibitor) abolished the HEMC-induced relaxation. The treatment with MDL-12,330A (adenylyl cyclase (AC) inhibitor) or diclofenac (COX inhibitor) reduced HEMC-induced vasorelaxation. The blockade of muscarinic and β-adrenergic receptors (by atropine and propranolol, resp.) did not promote changes in HEMC-induced vasorelaxation. In our in vivo studies, catheters were inserted into the right femoral vein and artery of anesthetized rats for HEMC infusion and the measurement of blood pressure, heart rate, and aortic blood flow. The intravenous infusion of HEMC produced hypotension and increased aortic blood flow with no changes in heart rate. These findings showed that HEMC induces endothelium-dependent vascular relaxation and hypotension with no alteration in heart rate. The NO/sGC/cGMP pathway seems to be the main cellular route involved in the vascular responsiveness.