Cuphea spp. : perfil fitoquímico, estudos in vitro da inibição da enzima conversora de angiotensina e da atividade antiquimiotáxica, otimização da extração, desenvolvimento e validação de método analítico

O gênero Cuphea (Lythraceae) compreende aproximadamente 108 espécies identificadas no Brasil. Vários estudos mostraram que Cuphea spp. têm potencial para atuar principalmente como antimicrobiano, anti-inflamatório, diurético, antihipertensivo e antitumoral. Investigações fitoquímicas indicaram a presença majoritária de compostos polifenólicos. O presente trabalho teve como objetivo investigar a composição química de quatro espécies de Cuphea encontradas no Rio Grande do Sul, avaliar a inibição da enzima conversora de angiotensina (ECA), in vitro, otimizar o método extrativo e validar o método para quantificação da miquelianina em C. glutinosa. Por fim, avaliar a atividade anti-inflamatória, in vitro, com a atividade antiquimiotáxica das espécies de Cuphea, e investigar o potencial antiinflamatório da miquelianina, in vivo, em modelo zebrafish. As análises químicas dos compostos foram realizadas por UHPLC-MS usando ESI-Q-TOF. Os ensaios de inibição da ECA foram determinados com base no método descrito por Tabatabei com algumas modificações, na concentração de 100 ng/mL e os valores foram determinados por experimentos em triplicata. As condições ótimas para a extração de miquelianina das folhas de C. glutinosa foram determinadas utilizando um planejamento fatorial fracionário (PFF) e um planejamento composto central (PCC). O método por UPLC-PDA foi validado, seguindo as diretrizes atuais. A atividade antiinflamatória, in vitro, foi avaliada pela capacidade de C. calophylla, C. carthagenensis, C. glutinosa, C. racemosa, e dos compostos isolados: miquelianina, miricitrina, além do controle positivo indometacina (em concentrações de 0,1 a 10 μg/mL) em inibir a migração de leucócitos pelo método de Boyden. Para atividade anti-inflamatória, in vivo, o indutor inflamatório (LPS) foi injetado no zebrafish por via intraperitoneal e após seis horas, nos grupos controle (PBS-negativo e dexametasona-positiva) e miquelianina foram injetadas as concentrações de 2,5, 7,5 e 15 mg/kg. Os grupos foram mantidos em aquários separados e após 24 horas, os animais foram sacrificados, dissecados e o cérebro congelado (-80ºC). Utilizando o homogenato cerebral, a modulação neuro-inflamatória foi avaliada (kits ELISA IL-1β e TNF-α). Os resultados mostraram 26 compostos polifenólicos, principalmente derivados de quercetina, miricetina e canferol. Desses compostos, dez são descritos no gênero pela primeira vez. A inibição da atividade da ECA apresentou como principais resultados: miquelianina 32,41%, C. glutinosa (31,66%), C. carthagenensis (26,12%) e C. calophylla (23,81%). Os resultados indicaram C. glutinosa como a espécie mais promissora. Assim sendo, a espécie teve a obtenção do seu extrato otimizado com os seguintes parâmetros: planta:solvente 1:60 (m/v), porcentagem de solvente etanol 38%, tempo de 60 minutos, cinco extrações e tamanho de partícula ≤ 180 μm. O método apresentou excelente seletividade, linearidade, precisão (repetibilidade e precisão intermediária abaixo de 2,18 e 1,40%, respectivamente) e acurácia (recuperação média de 90,6%). O conteúdo médio de miquelianina em C. glutinosa foi de 1,03%. A capacidade dos extratos hidroalcóolicos das espécies de Cuphea, miquelianina e miricitrina, de inibir a migração de leucócitos, foi estatisticamente significante em relação ao controle negativo (p <0,05). A inibição percentual variou de 23,5 a 100% para as amostras, enquanto a indometacina (controle positivo) inibiu 81,17%, na concentração de 10 μg/mL. Para todas as amostras, na concentração de 10 μg/mL, o efeito antiquimiotáxico foi significativamente maior (p <0,001), com porcentagens de inibição de 61,2, 62,3, 70,0, 76,0, 100 e 100% para C. carthagenensis, C. racemosa, C. glutinosa, miricitrina, C. calophylla e miquelianina, respectivamente. Em resposta ao modelo de neuro-inflamação, a miquelianina apresentou comportamento semelhante ao grupo controle (PBS), não demonstrando diferença significativa nas concentrações testadas. Resumidamente, os resultados obtidos sugerem que o potencial inibidor da ECA seja aumentado pela presença da miquelianina, além das interações entre os diferentes fitoconstituintes presentes no extrato. Além disso, observou-se que a otimização do método extrativo nas folhas de C. glutinosa aumentou a concentração de miquelianina no extrato bruto e o método foi validado de acordo com a legislação vigente. Com relação à inibição da inflamação, as amostras apresentaram efeito significativamente antiquimiotáxico, porém a miquelianina não inibiu a neuro-inflamação, in vivo, no modelo zebrafish, nas doses testadas. Portanto, o gênero Cuphea apresentou importância como agente antihipertensivo, corroborando com o uso popular, contudo novos ensaios com diferentes concentrações devem ser realizados em modelos experimentais, in vivo.Cuphea genus (Lythraceae) comprises approximately 108 identified species in Brazil. Several studies have shown that Cuphea spp. have the potential to act mainly as antimicrobial, anti-inflammatory, diuretic, anti-hypertensive and antitumor. Phytochemical investigations indicated the majority presence of polyphenolic compounds. Present work aimed to investigate the chemical composition of four Cuphea species found in Rio Grande do Sul, to assess the angiotensin-converting enzyme (ACE) inhibition, in vitro, besides optimize the extractive method and validate method for the quantification of the miquelianin in C. glutinosa. Lastly to evaluate the anti-inflammatory activity, in vitro, with the antichemotactic activity of the Cuphea species, and investigate the anti-inflammatory potential of the miquelianin, in vivo, in zebrafish model. The chemical analyses of the compounds were performed by UHPLC-MS using ESI-Q-TOF. The ACE inhibition assays were determined based on the method described by Tabatabei with some modifications, at concentration of 100 ng/mL and values were determined by triplicate experiments. The optimum conditions for the extraction of miquelianin from leaves of C. glutinosa were determined using a fractional factorial design (FFD) and a central composite design (CCD). An UPLC-PDA was validated method, following the guidelines current. The anti-inflammatory activity, in vitro, was assessed by ability of C. calophylla, C. carthagenensis, C. glutinosa, C. racemosa, and isolated compounds: miquelianin, myricitrin, besides the positive control indomethacin (at concentrations from 0.1 to 10 μg/mL) to inhibit leukocyte migration was assessed by the Boyden method. For anti-inflammatory activity, in vivo, inflammatory inducer (LPS) was injected in zebrafish intraperitoneally and after six hours, the control groups (PBS-negative and dexamethasone-positive) and miquelianin samples were injected at concentrations of 2.5, 7.5 and 15 mg/kg. The groups were kept in separate aquariums and after 24 hours, the animals were euthanized, dissected and the brains were freezed (at -80ºC). Using brain homogenate, the neuroinflammatory modulation was evaluated (IL-1β and TNF-α ELISA kits). The results showed twenty-six polyphenolic compounds, mostly derived from quercetin, myricetin and kaempferol. Of these compounds, ten are described in the genus for the first time. The inhibition of ACE activity presented as main results: miquelianin 32.41%, C. glutinosa (31.66%), C. carthagenensis (26.12%) and C. calophylla (23.81%). The results indicated C. glutinosa as the most promising species. Therefore, the species had the obtaining of the your optimized extract, with the following parameters: plant:solvent 1:60 (w/v), percentage solvent 38% ethanol, 60 min time, five extractions and particle size ≤ 180 μm. The method showed excellent selectivity, linearity, precision (repeatability and intermediate precision were below 2.18 and 1.40%, respectively) and accuracy (mean recovery 90.6%). The average content of miquelianin in the C. glutinosa was 1.03%. The ability of the hydroalcoholic extracts of Cuphea species, miquelianin and myricitrin to inhibit leukocyte migration, exerted statistically significant in relation to the negative control (p <0.05). Percentage inhibition varied from 23.5 to 100% for the samples, whereas indomethacin (positive control) inhibited 81.17%, at the concentrations of 10 μg/mL. In the concentration of 10 μg/mL all samples showed a significantly higher antichemotactic effect (p <0.001), with inhibition percentages of 61.2, 62.3, 70.0, 76.0, 100 and 100% for C. carthagenensis, C. racemosa, C. glutinosa, myricitrin, C. calophylla and miquelianin, respectively. In response to neuroinflammation model the miquelianin presented similar behavior to the control group (PBS), showing no significant difference in the tested concentrations. Briefly, the achieved results suggest that the ACE inhibitor potential may be increased by the miquelianin presence, besides the interactions between the different phytoconstituent present in the crude extract. Moreover, was observed that the optimization of the extractive method in the leaves of C. glutinosa increased the concentration of miquelianin in the crude extract and the method was validated according to the current legislation. Regarding the inhibition of inflammation, the samples showed a significantly antichemotactic effect, however the miquelianin, did not inhibit the neuroinflammation in zebrafish model, at the doses tested. Therefore, the Cuphea genus presented importance as antihypertensive agent, corroborating with popular usage, and new assays with different concentrations should be performed in experimental models, in vivo

Analytical methods of phytochemicals from the Cuphea genus - A review

Cuphea genus (Lythraceae) comprises about 260 species. The dispersion of the genus occurs in two mains geographic centers: North and South America, with Brazil being the most Cuphea species-rich country, with approximately 104 identified species. Still poorly studied, the number of papers about genus has been growing considerably. However, a review of its analytical methods has not been previously performed. Therefore, this review aims to provide studies about different chromatographic methods used for the separation, elucidation, and identification of metabolites present in species of the Cuphea genus. Research in scientific databases like Scopus, PubMed, and Science Direct were managed, and all references were analyzed. This review covers the relevant literature until May 2021, totalizing 22 studies described on 12 species of Cuphea. Most methods were employed for chemical analysis, and just one of them was validated for quantification purposes. Thus, this review provides a brief overview of the different chromatographic methods used in the separation, elucidation, and identification of compounds on different species of the Cuphea genus

Analytical methods of phytochemicals from the Cuphea genus : a review

Cuphea genus (Lythraceae) comprises about 260 species. The dispersion of the genus occurs in two mains geographic centers: North and South America, with Brazil being the most Cuphea species-rich country, with approximately 104 identified species. Still poorly studied, the number of papers about genus has been growing considerably. However, a review of its analytical methods has not been previously performed. Therefore, this review aims to provide studies about different chromatographic methods used for the separation, elucidation, and identification of metabolites present in species of the Cuphea genus. Research in scientific databases like Scopus, PubMed, and Science Direct were managed, and all references were analyzed. This review covers the relevant literature until May 2021, totalizing 22 studies described on 12 species of Cuphea. Most methods were employed for chemical analysis, and just one of them was validated for quantification purposes. Thus, this review provides a brief overview of the different chromatographic methods used in the separation, elucidation, and identification of compounds on different species of the Cuphea genus

Alkaloids in erythrina by UPLC-ESI-MS and in vivo hypotensive potential of extractive preparations

Erythrina species are used in popular medicine as sedative, anxiolytic, anti-inflammatory, and antihypertensive. In this work, we investigated the chemical composition of extracts obtained from leaves of E. falcata and E. crista-galli. The hypotensive potential of E. falcata and the mechanism of action were also studied. The extracts were obtained by maceration and infusion. The total content of phenolic compounds and flavonoids was estimated by spectrophotometric methods. The chemical constituents were studied performing a chromatographic analysis by UPLC-ESI-MS. For in vivo protocols, blood pressure and heart rate were measured by the invasive hemodynamic monitoring method. Different concentrations of extracts and drugs such as L-NAME, losartan, hexamethonium, and propranolol were administrated i.v.The results of total phenolic contents for E. falcata and E. cristagalli were 1.3193–1.4989mgGAE/mL for maceration and 0.8771–0.9506mgGAE/mL for infusion. In total flavonoids, the content was 7.7829–8.1976mg RE/g for maceration and 9.3471–10.4765 REmg/g for infusion. The chemical composition was based on alkaloids, suggesting the presence of erythristemine, 11-methoxyglucoerysodine, erysothiopine, 11-hydroxyerysodine-glucose, and 11-hydroxyerysotinone-rhamnoside. A potent dose-dependent hypotensive effect was observed for E. falcata, which may be related to the route of -adrenergic receptors

Chemical Composition and Hypotensive Effect of Campomanesia xanthocarpa

Campomanesia xanthocarpa is known in Brazil as Guabiroba and is popularly used for various diseases, such as inflammatory, renal, and digestive diseases and dyslipidemia. The aim of the study was to analyze the chemical composition and investigate the effects of aqueous extract of C. xanthocarpa on the blood pressure of normotensive rats, analyzing the possible action mechanism using experimental and in silico procedures. The extract was evaluated for total phenolic compounds and total flavonoid content. The chemical components were determined by HPLC analyses. Systolic and diastolic blood pressure and heart rate were measured with extract and drugs administration. The leaves of C. xanthocarpa presented the relevant content of phenolics and flavonoids, and we suggested the presence of chlorogenic acid, gallic acid, quercetin, and theobromine. The acute administration of aqueous extract of C. xanthocarpa has a dose-dependent hypotensive effect in normotensive rats, suggesting that the action mechanism may be mediated through the renin-angiotensin system by AT1 receptor blockade and sympathetic autonomic response. Docking studies showed models that indicated an interaction between chlorogenic acid and quercetin with the AT1 receptor (AT1R) active site. The findings of these docking studies suggest the potential of C. xanthocarpa constituents for use as preventive agents for blood pressure

Analytical methods of phytochemicals from the Cuphea genus - A review

Cuphea genus (Lythraceae) comprises about 260 species. The dispersion of the genus occurs in two mains geographic centers: North and South America, with Brazil being the most Cuphea species-rich country, with approximately 104 identified species. Still poorly studied, the number of papers about genus has been growing considerably. However, a review of its analytical methods has not been previously performed. Therefore, this review aims to provide studies about different chromatographic methods used for the separation, elucidation, and identification of metabolites present in species of the Cuphea genus. Research in scientific databases like Scopus, PubMed, and Science Direct were managed, and all references were analyzed. This review covers the relevant literature until May 2021, totalizing 22 studies described on 12 species of Cuphea. Most methods were employed for chemical analysis, and just one of them was validated for quantification purposes. Thus, this review provides a brief overview of the different chromatographic methods used in the separation, elucidation, and identification of compounds on different species of the Cuphea genus

Alkaloids in erythrina by UPLC-ESI-MS and in vivo hypotensive potential of extractive preparations

Erythrina species are used in popular medicine as sedative, anxiolytic, anti-inflammatory, and antihypertensive. In this work, we investigated the chemical composition of extracts obtained from leaves of E. falcata and E. crista-galli. The hypotensive potential of E. falcata and the mechanism of action were also studied. The extracts were obtained by maceration and infusion. The total content of phenolic compounds and flavonoids was estimated by spectrophotometric methods. The chemical constituents were studied performing a chromatographic analysis by UPLC-ESI-MS. For in vivo protocols, blood pressure and heart rate were measured by the invasive hemodynamic monitoring method. Different concentrations of extracts and drugs such as L-NAME, losartan, hexamethonium, and propranolol were administrated i.v.The results of total phenolic contents for E. falcata and E. cristagalli were 1.3193–1.4989mgGAE/mL for maceration and 0.8771–0.9506mgGAE/mL for infusion. In total flavonoids, the content was 7.7829–8.1976mg RE/g for maceration and 9.3471–10.4765 REmg/g for infusion. The chemical composition was based on alkaloids, suggesting the presence of erythristemine, 11-methoxyglucoerysodine, erysothiopine, 11-hydroxyerysodine-glucose, and 11-hydroxyerysotinone-rhamnoside. A potent dose-dependent hypotensive effect was observed for E. falcata, which may be related to the route of -adrenergic receptors