Achyrocline satureioides, popularly known as “marcela”, is a medicinal plant found in South America. This plant is rich in flavonoids, which have been reported to exert numerous biological ...activities. The aim of this study was to purify, identify and evaluate the mechanisms underlining anticancer activity of A. satureioides flavonoids in glioma cell lines (U87, U251 and C6) as well as their comparative toxicity in normal brain cells (primary astrocytes, neurons and organotypic hippocampal cultures). The main flavonoids present in A. satureioides are luteolin, quercetin, 3-O-methyl-quercetin and achyrobichalcone, the later a very unique metabolite present in this plant. Isolated flavonoids as well as A. satureioides extracts reduced proliferation and clonogenic survival, and induced apoptosis of glioma cell lines. In addition, A. satureioides flavonoids potentiated the cytotoxic effect and apoptosis induction by the glioma chemotherapeutic temozolomide (TMZ). Importantly, A. satureioides flavonoids were less cytotoxic to astrocytes, neuron:astrocytes co-cultures and hippocampal cultures if compared to gliomas. Investigation of 10 cancer-related pathways showed a reduced activation of MYC and the Map kinases ERK and JNK by A. satureioides flavonoid-enriched extract, an effect not observed when individual flavonoids were evaluated. Altogether, the herein presented results show that A. satureioides extract possesses a combination of flavonoids, some unique for this plant, which have synergistic anticancer activity and potential for further studies in vivo.
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•Isolated flavonoids from marcela reduced proliferation and clonogenic survival, and induced apoptosis of glioma cell lines;•Marcela flavonoids potentiated the cytotoxic effect and apoptosis induction by the glioma chemotherapeutic temozolomide;•Flavonoid combinations increased the antiproliferative activities.
The complexation of herbal constituents with cyclodextrin has been a useful tool to improve their aqueous solubility. However, the simultaneous complexation of these compounds still lacks detailed ...studies. The present study investigated the multicomplexation of quercetin (QCT), luteolin (LUT), and 3-O-methylquercetin (3OMQ) with (2-hydroxypropyl)-β-cyclodextrin (HPβCD), when they are simultaneously contained in a flavonoid-enriched fraction (FEF) of Achyrocline satureioides. The phase-solubility diagram revealed a linear correlation between the flavonoids solubility and the HPβCD concentration, demonstrating the formation of complexes with a 1:1 stoichiometric ratio, which was confirmed by ESI-MS. Negative ΔG
0
values indicated that complexation was spontaneous. Flavonoids/HPβCD interactions were evidenced by FT-IR, DSC, SEM, and 1D and 2D NMR. The last one showed the formation of inclusion complexes by insertion of the B-ring of the flavonoids into the cavity of HPβCD. Unexpectedly, the FEF/HPβCD complex showed a radical scavenger potential lower than the FEF. The HPLC analysis revealed that the complex contained different flavonoid ratio than the fraction. Thus, the antioxidant capacity of the samples was demonstrated to be related to the ratio among the flavonoids, rather than to the total flavonoids. These new findings are very useful for developing herbal cyclodextrin-based products from A. satureioides or other herbal products.
The biological properties of
have been mostly ascribed to its major flavonoids quercetin (QCT), luteolin (LUT), and 3-
-methylquercetin (3
MQ). The present study aimed to optimize the extraction by ...dynamic maceration of the major phenolic compounds in order to obtain in a subsequent step a flavonoid-enriched fraction (FEF) using high performance countercurrent chromatography (HPCCC). A 3-level Box-Behnken design (BBD) was applied to maximize the extraction of the substances, using the plant : solvent ratio (
), extraction time (
), and ethanol concentration (
) as factors. One-step HPCCC semipreparative separation with a solvent system composed of hexane : ethyl acetate : methanol : water (0.9 : 0.9 : 0.8 : 1.0, v/v) was employed to obtain the FEF. The second-order polynomial model was able to fit the experimental data adequately. The linear and quadratic terms of
were the most significant factors that affected all the responses. The positive linear term of
indicated a substantial increase in extraction yield, while the negative quadratic term showed a nonlinear tendency. Linear terms of
suggested a tendency to solvent saturation, except for QCT. The terms of
did not affect the responses substantially. The HPCCC method was found to be efficient and rapid for separating the FEF with 71% (w/w) flavonoid content. Overall, the developed extraction procedure coupled with HPCCC proved to be efficient for obtaining an enriched fraction with a very high content of flavonoids from
.
Hymenaea genus has been used in folk medicine in Brazil, but few studies investigated its toxicity profile. Thus, the aim of this study was to determine toxicological parameters of Hymenaea courbaril ...stem bark hydroalcoholic extract by utilizing three cell lines including murine macrophages (RAW 264.7), mouse fibroblast cells (L929) and human lung fibroblast (MRC-5), as well as Salmonella/microsome assay, and in vivo Caenorhabditis elegans model. The predominant detected phytoconstituents in the extract were coumarins, flavonoids, phenolics, tannins and saponins and by HPLC analysis, astilbin (AST) was found to be the main component. The DPPH assay demonstrated that H. courbaril hydroalcoholic extract exhibited potent antioxidant activity, with an IC
50
of 3.12 μg/ml. The extract at concentrations of 400 and 800 μg/ml decreased cell viability 48 hr after treatment in L929 and MRC-5 cell lines. In the Raw 264.7 strain, just the highest concentration (800 μg/ml) lowered cell viability within 48 hr following exposure. The concentration of 100 μg/ml did not markedly affect cell viability in the trypan blue assay. In the alkaline comet assay the extract was found to be non-genotoxic. In the Ames test, the extract exhibited low mutagenic potential without metabolic activation, since only the highest concentrations produced an effect. H. courbaril extract only affected the survival of C. elegans at concentrations of 800 and 1600 μl/ml. These findings demonstrate that H. courbaril extract appears to exert low toxicity as evidenced in vitro and mutagenicity assays; however, the biological relevance of the response of C. elegans survival to safety assessments needs further studies.
Abstract
We evaluated the impact of an
Achyrocline satureioides
inflorescence infusion on the clinical outcomes of viral respiratory infections, including those caused by SARS‐CoV‐2, in a ...monocentric, randomized, open‐label, placebo‐controlled clinical trial. Patients with symptoms of viral respiratory infection, including suspected cases of COVID‐19, were included and assigned to receive either
A. satureioides
(
n
= 57) or
Malus domestica (n
= 67) infusions twice a day for 14 days. All participants were included before the RT‐PCR results, performed using a nasopharyngeal swab. The patients were further divided into subgroups according to real‐time polymerase chain reaction results: SARS‐CoV‐2‐positive and SARS‐CoV‐2‐negative subgroups for statistical analyses. We assessed clinical outcomes, such as the latency to resolution of cough, dyspnea, fever, sore throat, chest pain, smell and taste dysfunctions, diarrhea, nausea, abdominal pain, and loss of appetite; hospitalization; and mortality with questionnaires and medical records. The subjects that received early
A. satureioides
infusion showed a significant reduction in the average number of days with respiratory and neurological symptoms compared with the control group (
M. domestica
infusion). We conclude that
A. satureioides
is a safe agent and, in combination with standard care, improves viral respiratory infection symptoms, especially those related to COVID‐19.
This study investigated the inhibitory effects of Achyrocline satureioides extract (ASE) incorporated into a topical nanoemulsion on Herpes Simplex Virus type 1 (HSV-1/KOS strain) replication, as ...well as the distribution of the main ASE flavonoids (quercetin, luteolin, and 3-O-methylquercetin) in porcine skin and mucosa. The ASE-loaded nanoemulsion showed more pronounced effects against HSV-1 replication when compared to the ASE or pure quercetin, as determined by the viral plaque number reduction assay. All flavonoids were detected in the skin epidermis (2.2 µg/cm2) and the mucosa upper layers (3.0 µg/cm2) from ASE-loaded nanoemulsion until 8 h after topical application. A higher amount of flavonoids was detected when these tissues were impaired, especially in deeper mucosa layers (up to 7-fold). Flavonoids were detected in the receptor fluid only when the mucosa was injured. Such results were supported by confocal microscopy images. Overall, these findings suggest that the tested ASE-loaded nanoemulsion has potential to be used topically for herpes infections.
Pterostilbene is a natural constituent with numerous preventive and therapeutic properties used for treating a wide range of human diseases. It has been isolated from blueberries in high ...concentrations. A versatile specific-stability indicating liquid chromatography method for reliable quantitative determination of pterostilbene in blueberry extracts was developed. In the stability-indicating analysis, pterostilbene samples were exposed to stress conditions: temperature, UV light, and oxidative, acid and alkaline media. The robustness of the method was evaluated using a Box-Behnken experimental design. Pterostilbene was stable in acid and alkaline media, but unstable when exposed to oxidation, high temperature, and UV light. Using the proposed method, it was demonstrated that degradation products did not interfere in the analyte analysis. The method revealed to be simple, fast, selective, linear, precise and accurate for the quantitative analysis of pterostilbene in
Vaccinium myrtillus
extract. Besides being a specific-stability indicating method, it demonstrated to be applicable to quantify pterostilbene in pterostilbene:β-cyclodextrin complexes and pterostilbene:β-cyclodextrin:hydrophilic polymer ternary systems. These findings are relevant for the development of food, pharmaceutical or cosmetic products containing pterostilbene or blueberry extracts.
Pterostilbene is a natural constituent present in blueberries and other fruits, with several preventive and therapeutic properties for human health.
This study explored the effect of pterostilbene (PTS) complexed with hydroxypropyl-β-cyclodextrin (HPβCD) on right heart function, glutathione and glutaredoxin systems, and the expression of ...redox-sensitive proteins involved with regulation calcium levels in the experimental model of pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT). After 7 days of PAH induction, rats received daily doses of the PTS:HPβCD complex (corresponding to 25, 50, or 100 mg·kg
−1
of PTS) or vehicle (control group, CTR0) (an aqueous solution containing HPβCD; CTR0 and MCT0 (MCT group that did not receive PTS treatment)) via oral administration for 2 weeks. The results showed that the PTS:HPβCD complex increased the content of reduced glutathione and the activity of glutathione-S-transferase and glutaredoxin in the right ventricle (RV) of MCT-treated rats in a dose-dependent manner. Additionally, at higher doses, it also prevented the reduction of stroke volume and cardiac output, prevented myocardial performance index (MPI) increase, reduced lipoperoxidation, reduced total phospholamban, and increased the expression of sarcoplasmic reticulum calcium ATPase in the RV of MCT-treated rats. These results demonstrate that the PTS:HPβCD complex has a dose-dependent antioxidant mechanism that results in improved cardiac function in experimental right heart failure. Our results open a field of possibilities to PTS administration as new therapeutic approach to conventional therapy for right ventricular dysfunction.
Novelty
Pterostilbene complexed with hydroxypropyl-β-cyclodextrin could be a new therapeutic approach.
Pterostilbene complexed with hydroxypropyl-β-cyclodextrin reestablishes redox homeostasis through glutathione metabolism modulation, leading to an improved MPI in pulmonary arterial hypertension-provoked right heart failure.
Introduction
Phenolic compounds present in Achyrocline satureioides are known to have therapeutic benefits like antioxidant, anti‐inflammatory, and antitumour properties. The main polyphenols present ...in the plant are quercetin (QCT), luteolin (LUT), 3‐O‐methylquercetin (3OMQ), and achyrobichalcone (ACB). However, the effective isolation and purification of these compounds from A. satureioides inflorescences are not an easy task.
Objective
To develop an efficient high‐performance counter‐current chromatography (HPCCC) method for quick separation and purification of naturally occurring phenolic compounds from the extract of A. satureioides.
Methodology
A two‐step HPCCC semi‐preparative isolation method was developed using a solvent system composed of n‐hexane/ethyl acetate/methanol/water (0.8:1.0:0.8:1.0) and dichloromethane/methanol/water (3.5:3.5:2.5).
Results
The HPCCC method was used to obtain two fractions. The first fraction (F1) contained high levels of ACB, among other constituents, while the second fraction (F2) contained mostly QCT, LUT, and 3OMQ. Besides the high ACB content, F1 contained three other flavonoid‐aglycones (kaempferol, 97.3%; isokaempferide, 92.4%; and 3,3′‐di‐O‐methylquercetin, 95.2%) identified by an ultra‐performance liquid chromatography system coupled to a quadrupole time‐of‐flight with high‐definition mass spectrometry (UPLC‐QTOF/HDMS) and nuclear magnetic resonance (NMR) analysis. Purity levels of ACB, 3OMQ, QCT, and LUT were 98.0, 97.0, 97.5, and 90.2%, respectively.
Conclusion
This is the first time that high purity ACB and six other flavonoids were obtained from A. satureioides inflorescences by HPCCC. These excellent results reveal the potential and versatility of HPCCC as a technique to produce different types of products from this plant species on a semi‐preparative scale: enriched fractions, new metabolites, or high purity compounds.
Phenolic compounds present in Achyrocline satureioides are known to have therapeutic benefits. Quercetin (QCT), luteolin (LUT), 3‐O‐methylquercetin (3OMQ), and achyrobichalcone (ACB) are the main phenolics present in the specie. HPCCC method was used to isolate this phenolics in semi‐preparative scale. Besides the isolation of high purity ACB, three other flavonoid‐aglycones (kaempferol, isokaempferide, and 3,3′‐di‐O‐methylquercetin) could be identified by ultra‐performance liquid chromatography system coupled to a quadrupole time‐of‐flight with high definition mass spectrometry (UPLC‐QTOF/HDMS) and nuclear magnetic resonance (NMR) analysis.
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