Naringenin attenuates cerebral ischemia/reperfusion injury by inhibiting oxidative stress and inflammatory response via the activation of SIRT1/FOXO1 signaling pathway in vitro

Purpose: To explore the protection of naringenin against oxygen-glucose deprivation/reperfusion (OGD/R)-induced HT22 cell injury, a cell model of cerebral ischemia/reperfusion (I/R) injury in vitro, focusing on SIRT1/FOXO1 signaling pathway. Methods: Cytotoxicity, apoptosis, reactive oxygen species (ROS) generation, malondialdehyde (MDA) content, 4-hydroxynonenoic acid (4-HNE) level, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) activities were measured by commercial kits. Inflammatory cytokines levels were determined by enzyme-linked immunosorbent assay (ELISA). The protein expressions were monitored by Western blot analysis. Results: Naringenin significantly ameliorated OGD/Rinduced cytotoxicity and apoptosis in HT22 cells. Meanwhile, naringenin promoted SIRT1 and FOXO1 protein expressions in OGD/R-subjected HT22 cells. In addition, naringenin attenuated OGD/R-induced cytotoxicity, apoptosis, oxidative stress (the increased ROS, MDA and 4-HNE levels, and the decreased SOD, GSH-Px and CAT activities) and inflammatory response (the increased tumor necrosis factor-α, interleukin [IL]-1ß, and IL-6 levels and the decreased IL-10 level), which were blocked by the inhibition of the SIRT1/FOXO1 signaling pathway induced by SIRT1-siRNA transfection. Conclusion: Naringenin protected HT22 cells against OGD/R injury depending on its antioxidant and anti-inflammatory activities via promoting the SIRT1/FOXO1 signaling pathway.

Naringin is a promising natural compound for therapy of iron-overload disorders

Abstract Naringin has been shown to exhibit satisfying iron chelation capacity. Considering the side effects of routinely-used iron chelator (desferrioxamine, DFO), we decided to evaluate the iron chelation potency of naringin to discover whether or not it can be a promising natural substitute for treatment of excessive iron-related diseases. 35 mice were classified into five groups of 7 and subjected to iron dextran administration to induce the iron-overload condition. Iron-overloaded mice were then treated with normal saline (as control), naringin or DFO Morphology changes, and iron deposition in liver tissues were studied using H&E and Perl's staining. The results revealed that naringin is more potent than DFO in removing excessive iron ions deposited in liver tissues, indicating that naringin is a promising natural compound for therapy of iron overload disorders

A new combination of naringin and trimetazidine protect kidney Mitochondria dysfunction induced by renal Ischemia / Reperfusion injury in rat

Abstract Ischemia/reperfusion (IR) injury leads to overproduction of Reactive Oxygen Species (ROS), and disrupts membrane potential that contributes to cell death. The aim of this study was to determine if naringin (NAR), trimetazidine (TMZ) or their combination, protect the kidney mitochondrial from IR injury. Forty rats were randomly allocated into five groups, harboring eight rats each: Sham, IR, NAR (100 mg/kg), TMZ (5 mg/kg) and NAR plus TMZ. Ischemia was induced by obstructing both renal pedicles for 45 min, followed by reperfusion for 4 hours. The mitochondria were isolated to examine the ROS, Malondialdehyde (MDA), Glutathione (GSH), mitochondrial membrane potential (MMP) and mitochondrial viability (MTT). Our findings indicated that IR injury resulted in excessive ROS production, increased MDA levels and decreased GSH, MMP and MMT levels. However, NAR, TMZ or their combination reversed these changes. Interestingly, a higher protection was noted with the combination of both, compared to each drug alone. We speculate that this combination demonstrates a promising process for controlling renal failure, especially with the poor clinical outcome, acquired with NAR alone. This study revealed that pretreatment their combination serves as a promising compound against oxidative stress, leading to suppression of mitochondrial stress pathway and elevation of GSH level.

Naringin attenuates acute myocardial ischemia-reperfusion injury via miR126/GSK-3ß/ß-catenin signaling pathway

Introduction: Myocardial ischemia-reperfusion (I/R) injury is one of the mechanisms contributing to the high mortality rate of acute myocardial infarction. Purpose: This study intended to study the role of naringin in cardiac I/R injury. Methods: AC16 cells (human cardiomyocyte cell line) were subjected to oxygen-glucose deprivation/recovery (OGD/R) treatment and/or naringin pretreatment. Then, the apoptosis was examined by flow cytometry and Western blotting. The concentration of IL-6, IL-8 and TNF-α was measured by enzyme-linked immunosorbent assay (ELISA) kits. How naringin influenced microRNA expression was examined by microarrays and quantitative real-time polymerase chain reaction (qRT-PCR). Dual luciferase reporter assay was employed to evaluate the interaction between miR-126 and GSK-3ß. The GSK-3ß/ß-catenin signaling pathway was examined by Western blotting. Finally, rat myocardial I/R model was created to examine the effects of naringin in vivo. Results: Naringin pretreatment significantly decreased the cytokine release and apoptosis of cardiomyocytes exposed to OGD/R. Bioinformatical analysis revealed that naringin upregulated miR-126 expression considerably. Also, it was found that miR-126 can bind GSK-3ß and downregulate its expression, suggesting that naringin could decrease GSK-3ß activity. Next, we discovered that naringin increased ß-catenin activity in cardiomyocytes treated with OGD/R by inhibiting GSK-3ß expression. Our animal experiments showed that naringin pre-treatment or miR-126 agomir alleviated myocardial I/R. Conclusions: Naringin preconditioning can reduce myocardial I/R injury via regulating miR-126/GSK-3ß/ß-catenin signaling pathway, and this chemical can be used to treat acute myocardial infarction.

Phytochemical composition and biological screening of two Lophophytum species / Composición fitoquímica y cribado biológico de dos especies de Lophophytum

Lophophytum species are holoparasites that grow on tree roots. The objectives of the work were to explore the chemical composition of the tubers of two Lophophytum species and to analyze the antioxidant, anti-inflammatory and antilithiatic activity of their extracts using in vitro methods. The chemical composition was determined by histochemical, phytochemical and TLC tests. In addition, the profile of phenolic compounds was determined by HPLC-MS. The presence of secondary metabolites of recognized activity was demonstrated. The results of the HPLC-MS/MS allowed the tentative identification of catechin, luteolin and glycosides of eriodictyol, naringenin and luteolin in the extract of Lophophytum leandriand eriodictyol, naringenin, luteolin and their glycosylated derivatives in Lophophytum mirabile. The extracts showed promising antioxidant (DPPH, ABTS and ß-carotene-linoleic acid), anti-inflammatory (inhibition of 5-LOX) and anti-urolytic (by bioautographic TLC) activity. It is noteworthy that these are the first results of the phytochemical composition and biological activity of L. mirabile. However, in vivo studies are required to corroborate these activities.

Las especies de Lophophytumson holoparásitas que crecen en raíces de árboles. Los objetivos del trabajo fueron explorar la composición química del túber de dos especies de Lophophytum y analizar la actividad antioxidante, antiinflamatoria y antilitiásica de sus extractos usando métodos in vitro. La composición química se determinó mediante pruebas histoquímicas, fitoquímicas y por TLC. Además, se determinó el perfil de compuestos fenólicos por HPLC-MS/MS. Se demostró presencia de metabolitos secundarios de reconocida actividad. Los resultados del HPLC-MS/MS permitieron identificar tentativamente catequina, luteolina y glucósidos de eriodictiol, naringenina y luteolina en el extracto de Lophophytum leandriy eriodictiol, naringenina, luteolina y sus derivados glicosilados en Lophophytum mirabile. Los extractos mostraron prometedora actividad antioxidante (DPPH, ABTS y ß-caroteno-ácido linoleico), antiinflammatoria (inhibición de la 5-LOX) y antiurolitiásica (por TLC bioautográfica). Es de destacar que estos son los primeros resultados de composición fitoquímica y actividad biológica de L. mirabile. Sin embargo, se requieren estudios in vivo para corroborar dichas actividades.

Naringin and trimetazidine improve baroreflex sensitivity and nucleus tractus solitarius electrical activity in renal ischemia-reperfusion injury / Naringin and trimetazidine improve baroreflex sensitivity and nucleus tractus solitarius electrical activity in renal ischemia-reperfusion injury

Resumo Fundamento: O núcleo do trato solitário (NTS) é uma área do cérebro que desempenha um papel fundamental na regulação renal e cardiovascular através dos impulsos dos barorreceptores. Objetivos: O objetivo deste estudo foi avaliar o efeito da Naringina (NAR) e trimetazidina (TMZ), isoladamente e combinadas, na atividade elétrica do NTS e na sensibilidade barorreflexa (SBR) na lesão de isquemia e reperfusão (I/R) renal. Métodos: Foram utilizados quarenta ratos machos Sprague-Dawley (200-250 g), alocados em 5 grupos com 8 ratos cada. Grupos: 1) Sham; 2) I/R; 3) TMZ 5 mg/kg; 4) NAR 100 mg/kg; e 5) TMZ5 + NAR100. A veia femoral esquerda foi canulada para infundir a solução salina ou droga e avaliar a SBR. A I/R foi induzida por oclusão dos pedículos renais por 45 min, seguida de reperfusão de 4 horas. O eletroencefalograma local do NTS foi registrado antes, durante a isquemia e durante a reperfusão. A fenilefrina foi injetada por via intravenosa para avaliar a SBR ao final do tempo de reperfusão. Os dados foram analisados por ANOVA de duas vias com medidas repetidas seguida pelo teste post hoc de Tukey. Um valor de p<0,05 foi considerado como significativo. Resultados: As ondas elétricas do NTS não se alteraram durante o tempo de isquemia, mas diminuíram significativamente durante todos os tempos de reperfusão. A atividade elétrica do NTS e a SBR foram reduzidas drasticamente em ratos com lesão I/R; no entanto, a administração de NAR e TMZ, isoladamente e combinadas, melhorou significativamente essas alterações em ratos com lesão I/R. Conclusões: Os resultados mostraram que a lesão de I/R leva à redução da atividade elétrica da SBR e do NTS, e pode haver uma ligação entre a I/R e a diminuição da SBR. Além disso, a NAR e a TMZ são agentes promissores para tratar complicações de I/R.

Abstract Background: Nucleus tractus solitarius (NTS) is a brain area that plays a key role in kidney and cardiovascular regulation via baroreceptors impulses. Objectives: The aim of this study was to evaluate the effect of naringin (NAR) and trimetazidine (TMZ) alone and their combination on NTS electrical activity and baroreceptor sensitivity (BRS) in renal ischemia- reperfusion (I/R) injury. Methods: Forty male Sprague-Dawley rats (200- 250 g) were allocated into 5 groups with 8 in each. 1) Sham; 2) I/R; 3) TMZ 5 mg/kg; 4) NAR 100 mg/kg; and 5) TMZ5+ NAR100. The left femoral vein was cannulated to infuse saline solution or drug and the BRS was evaluated. I/R was induced by occlusion of renal pedicles for 45 min, followed by 4 hours of reperfusion. The NTS local electroencephalogram (EEG) was recorded before, during ischemia and throughout the reperfusion. Phenylephrine was injected intravenously to evaluate BRS at the end of reperfusion time. The data were analyzed by two-way repeated measurement ANOVA followed by Tukey's post hoc test. A p-value <0.05 was considered significant. Results: NTS electrical waves did not change during ischemia time, while they significantly decreased during the entire reperfusion time. NTS electrical activity and BRS dramatically reduced in rats with I/R injury; however, administration of NAR, TMZ alone or their combination significantly improved these changes in rats with I/R injury. Conclusions: The results showed that I/R injury leads to reduced BRS and NTS electrical activity and there may be an association between I/R and decreased BRS. In addition, NAR and TMZ are promising agents to treat I/R complications.

Naringenin promotes cell autophagy to improve high-fat-diet-induced atherosclerosis in ApoE-/- mice

Naringenin (NAR) is a major flavanone in citrus fruits that has multiple pharmacological attributes such as anticancer and antiatherogenic. This study aims to investigate the mechanism of NAR in high-fat-diet (HFD)-induced atherosclerosis (AS) in apolipoprotein E-knockout (ApoE-/-) mice. A HFD-induced AS ApoE-/- mouse model was established. The mice were treated with HFD, different doses of NAR and simvastatin (Simv). After drug treatment, the levels of total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), superoxide dismutase (SOD), and alanine aminotransferase (ALT) were determined. The expression of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) was detected using qRT-PCR and enzyme-linked immunosorbent assay. The plaque area of the aorta of AS mice was determined using oil red O staining. Western blot analysis was applied to measure the levels of autophagy-related proteins [protein 1 light chain 3B (LC3B), beclin 1, and p62]. The TC, TG, LDL-C, TNF-α, ALT, and MDA levels were significantly increased while the HDL-C, SOD, and GSH-Px levels were decreased in the HFD-induced AS ApoE-/- mice. NAR treatment reversed the expression of the above indicators in mice. After they were treated with different doses of NAR, the LC3B and beclin 1 levels were improved while the p62 protein level was decreased. This study suggested that NAR could promote cell autophagy to improve HFD-induced AS in ApoE-/- mice.

Citotoxicidade e efeito indutor de mineralização de flavonoides sobre células osteoblásticas / Cytotoxicity and inducing effect of mineralization of flavonoids on osteoblastic cells

A perda óssea dentária e a formação de lesões periapicais surgem como uma consequênc ia do desequilíbrio da homeostase óssea. Os osteoblastos, juntamente com os osteoclastos e osteócitos, atuam na formação e na reabsorção óssea. Vários marcadores de formação óssea são produzidos por osteoblastos ativos e refletem diferentes aspectos da dif erenciação osteoblástica e da remodelação óssea. Com isso, muitos autores têm explorado o uso de fitoterápicos, visando obter novos compostos que apresentem propriedades terapêuticas, como os flavonoides, e que estimulem a neoformação óssea e o reparo da r egião periapical. O objetivo deste estudo foi avaliar in vitro a citotoxicidade e efeito indutor de mineralização de flavonoides sobre células osteoblásticas humanas. Para isso, células osteoblásticas da linhagem Saos expostas aos seguintes flavono2 foram ides: quercetina, miricetina e seus derivados taxifolina, isoquercitrina, rutina, ampelopsina e EGCG, além de pinocembrina, crisina e canferol, de forma isolada e combinada. Foi avaliado o efeito citotóxico, a atividade de fosfatase alcalina e indução de n mé todo de Shapiroódulos de mineralização. Os resultados foram analisados p elo Wilk, e as variáveis foram submetidas à análise de ANOVA seguida pelo teste de Tukey para comparar entre os grupos e/ou concentrações ou teste de Dunnett para comparar entre cada grupo e o controle, com nível de significância de 5%. A viabilidade da cultura de osteoblastos não teve uma redução estatisticamente significativa na presença da maioria dos compostos, exceto crisina a 100µM. Taxifolina, isoquercitrina, rutina, ampelopsina e EGCG foram os compostos que estimularam significativamente a atividade da fosfatase alcalina, juntamente com as combinações taxifolina+isoquercitrina, taxifolina+ampelopsina e taxifolina+rutina a 25/25 µM. Quanto a formação de nódulos de mine ralização, ampelopsina, isoquercitrina, rutina, pinocembrina e miricetina isolados e taxifolina+isoquercitrina, taxifolina+ampelopsina e taxifolina+rutina combinados obtiveram os melhores resultados, variando de acordo com as concentrações. Concluise que a taxifolina, isoquercitrina, rutina e ampelopsina e combinações de taxifolina com esses flavonoides são citocompatíveis e apresentam efeito indutor de mineralização em osteoblastos Saos-2(AU)

Dental bone loss and the formation of periapical lesions arise as a consequence of imbalance of bone homeostasis. Osteoblasts, together with osteoclasts and osteocytes, act in bone formation and resorption. Several markers of bone formation are produced by active osteoblasts and reflect different aspects of osteoblastic differentiation and bone remodeling. Thus, many authors have explored the use of phytotherapics in order to obtain new compounds with therapeutic properties, such as flavonoids, and also stimulate bone neoformation and periapical region repair. The objective of this study was to evaluate in vitro the cytotoxicity and inducing effect of flavonoid mineralization on human osteoblastic cells. For this, osteoblastic cells of the Saos-2 lineage were exposed to the following flavonoids: quercetin, myricetin and its derivatives taxifoline, isoquercitrin, rutin, ampelopsin and EGCG, in addition to pinocembrin, chrysin and kaempferol, in an isolated and combined manner. The cytotoxic effect, the activity of alkaline phosphatase and the induction of mineralization nodules were evaluated. The results were analyzed using the Shapiro-Wilk method, and the variables were submitted to ANOVA analysis followed by the Tukey test to compare between groups and/or concentrations or Dunnett's test to compare between each group and the control, with a level of 5% significance. The viability of the osteoblast culture did not have a statistically significant reduction in the presence of most compounds, except 100 µM chrysin. Taxifoline, isoquercitrin, rutin, ampelopsin and EGCG were the compounds that significantly stimulated the activity of alkaline phosphatase, together with the combinations taxifoline+isoquercitrin, taxifoline+ampelopsin and taxifoline+rutin at 25/25 µM. As for the formation of mineralization nodules, ampelopsin, isoquercitrin, rutin, pinocembrin and myricetin alone and taxifoline+isoquercitrin, taxifoline+ampelopsin and taxifoline+rutin combined obtained the best results, varying according to the concentrations. It is concluded that taxifoline, isoquercitrin, rutin and ampelopsin and combinations of taxifolin with these flavonoids are cytocompatible and have a mineralization-inducing effect on Saos-2 osteoblasts(AU)

Baicalein restrains proliferation, migration, and invasion of human malignant melanoma cells by down-regulating colon cancer associated transcript-1

Baicalein (BAI) is an acknowledged flavonoids compound, which is regarded as a useful therapeutic pharmaceutical for numerous cancers. However, its involvement in melanoma is largely unknown. This study aimed to examine the anti-melanoma function of BAI and unraveled the regulatory mechanism involved. A375 and SK-MEL-28 were treated with BAI for 24 h. Then, CCK-8 assay, flow cytometry, and transwell assay were carried out to investigate cell growth, migration, and invasion. RT-qPCR was applied to detect the expression of colon cancer associated transcript-1 (CCAT1) in melanoma tissues and cells. The functions of CCAT1 in melanoma cells were also evaluated. Western blot was utilized to appraise Wnt/β-catenin or MEK/ERK pathways. BAI restrained cell proliferation and stimulated cell apoptotic capability of melanoma by suppressing cleaved-caspase-3 and cleaved-PARP. Cell migratory and invasive abilities were restrained by BAI via inhibiting MMP-2 and vimentin. CCAT1 was over-expressed in melanoma tissues and down-regulated by BAI in melanoma cells. Overexpressed CCAT1 reversed the BAI-induced anti-growth, anti-migratory, and anti-invasive effects. Furthermore, BAI inhibited Wnt/β-catenin and MEK/ERK pathways-axis via regulating CCAT1. Our study indicated that BAI blocked Wnt/β-catenin and MEK/ERK pathways via regulating CCAT1, thereby inhibiting melanoma cell proliferation, migration, and invasion.

Estudo comparativo da excreção de flavonoides entre indivíduos eutróficos e obesos, após a ingestão de sucos de laranja, cv. Pera e cv. Moro / Comparative study of excretion of flavonoids among eutrophic and obese individuals, after ingestion of orange juice, cv. Pera and cv Moro

As laranjas e seus derivados, principalmente os sucos, possuem compostos bioativos, tais como os flavonoides, entre eles as flavanonas hesperidina e narirutina, que podem estar relacionados à promoção e benefícios à saúde. A absorção e metabolização de flavonoides podem ser afetadas por diversos fatores como a microbiota e fatores antropométricos, o que pode afetar a sua bioatividade. Assim, o objetivo deste estudo foi comparar o metabolismo e excreção dos flavonoides entre indivíduos eutróficos e obesos após a ingestão de sucos de laranja pasteurizado obtidos das cvs. Pera e Moro. Em um estudo cross-over randomizado 20 voluntárias eutróficas e 10 voluntárias obesas, com idade entre 19 e 40 anos, consumiram em dose única 600 mL de cada suco, que contém as flavanonas narirutina e hesperidina, além das antocianinas no suco Moro. Os metabólitos de flavanonas e de antocianinas foram identificados e quantificados em urina coletada em diferentes períodos de tempo durante 24 horas. Não foi observada diferença significativa na permeabilidade intestinal entre os grupos. Foram detectados e identificados 8 metabólitos de fase II da hesperitina e naringenina, principalmente mono e diglicuronidados e sulfatos, além de três ácidos fenólicos catabólitos de flavanonas formados pela microbiota intestinal, entre elas o ácido hipúrico, ácido protocatecuico e ácido 3-(3-hidroxifenil)-3-hidroxipropiônico. Os ácidos fenólicos foram os metabólitos majoritários recuperados na urina, principalmente o ácido hipúrico. Ainda, os metabólitos de fase II apresentaram maior excreção entre o período de 4-8h e 8-12h (13 a 27% do total de metabólitos excretados). Não foi observada diferença significante (p<0,05) no total de metabólitos de naringenina e hesperitina excretados na urina durante o período de 24 h entre os dois grupos e para os sucos de laranja, nem para o total de metabólitos, provavelmente devido à grande variabilidade interindividual na excreção. Assim, não foi observada diferença entre a metabolização de flavanonas de laranja entre os eutróficos e obesos e nenhuma correlação com os parâmetros antropométricos avaliados

Oranges and orange juices contain bioactive compounds, such as flavonoids, mainly the flavanones hesperidin and narirutin, which may be related to the promotion and health benefits. The absorption and metabolization of flavonoids can be affected by several factors such as the gut microbiota and anthropometric parameters, which may affect its bioactivity. Thus, the aim of this study was to compare the metabolism and excretion of flavonoids among eutrophic and obese people after ingestion of two pasteurized orange juice obtained from cvs. Pera and Moro. In a randomized cross-over study 20 eutrophic volunteers and 10 obese volunteers, aged 19-40 years, consumed a single dose of 600 mL of each juice. The metabolites of flavanones and anthocyanins were identified and quantified in urine collected at different time points for 24 hours. No significant difference in intestinal permeability was observed between groups. Eight Phase II metabolites of hesperitin and naringenin, mainly mono and diglycerides and sulfates, and three phenolic catabolites of flavanones formed by the gut microbiota were detected and identified, among them hippuric acid, protocatecuic acid and 3- (3-hydroxyphenyl) ) -3-hydroxypropionic acid. Phenolic acids were the major metabolites recovered in urine, mainly hippuric acid. Furthermore, phase II metabolites had greater excretion between the period of 4-8h and 8-12h (13-27% of total metabolites excreted). No significant difference (p <0.05) was observed in the total of naringenin and hesperitin metabolites excreted in the urine during the 24 h period between the two groups, probably due to interindividual variability in excretion. Thus, no difference was observed on metabolism of flavanones between the eutrophic and obese and no correlation was observed with the anthropometric parameters evaluated

Cuantificación de los compuestos bioactivos y capacidad antioxidante del hongo Cordyceps sinensis para su uso potencial como aditivo alimentario / Quantification of the bioactive compounds and antioxidant capacity of the Cordyceps sinensis fungus for its potential use as a food additive

El uso de antioxidantes contribuye a disminuir el deterioro de los alimentos. Una práctica común en la actualidad es el uso de aditivos alimentarios de origen sintético, como el butilhidroxitolueno (BHT) y butilhidroxianisol (BHA). El hongo Cordyceps sinensis es ampliamente usado en la medicina asiática y se ha encontrado que aporta múltiples beneficios. Con el fin de evaluar la capacidad antioxidante de este hongo como aditivo alimentario, se obtuvieron extractos a partir de harina de C. sinensis, utilizando extracto acuoso (T1), etanólico (T2), acuoso-etanólico (T3) y acuoso a 50 °C (T4) (en una relación soluto/solvente de 100 g/900 mL c/u). Para la harina se determinó la composición química proximal, obteniendo alto contenido de carbohidratos (80%), y valores bajos de humedad, proteína, grasa y cenizas (<10%). Se determinó el contenido de fitoquímicos, incluyendo contenido de polisacáridos totales (CPT), fenoles totales (CFT), flavonoides totales (CFvT), flavonas y flavonoles totales (CFFT), flavanonas y dihidroflavonoles totales (CFDT), y ácido clorogénico (CAC). Además, actividad antirradical DPPH y ABTS, así como poder reductor (PR). Los resultados indicaron que el extracto T3, seguido del extracto T1, presentaron la mayor capacidad antioxidante (DPPH. ABTS y PR), lo cual fue asociado con el CFT, CFFT, y CFDT, así como CPT, CFvT y CAC, respectivamente. Se recomienda evaluar el efecto de la adición de los extractos obtenidos de la harina de C. sinensis sobre la estabilidad oxidativa y microbiológica de productos cárnicos.

Avaliação in vitro do sêmen congelado de carneiros com diluidor suplementado com miricetina / In vitro evaluation of ram sperm frozen with extender supplemented with myricetin

O objetivo deste estudo foi avaliar o efeito da suplementação do diluidor de congelação de sêmen ovino com o flavonoide miricetina contra os danos ocasionados aos espermatozoides. Oito pools de sêmen, obtidos de quatro reprodutores ovinos, foram congelados com diferentes concentrações de miricetina (0, 1, 10, 100 e 1000nM). Após o descongelamento, o sêmen foi avaliado quanto à cinética espermática, à integridade das membranas plasmática e acrossomal, ao potencial de membrana mitocondrial, aos níveis de ROS intracelular, à peroxidação lipídica e à estabilidade de membrana. Amostras tratadas com miricetina 10nM apresentaram menor percentual de células rápidas (P≤0,05), quando comparadas ao grupo miricetina 1000nM. Amostras do grupo controle apresentaram maior (P≤0,05) VAP que o grupo 10nM de miricetina, enquanto amostras criopreservadas com miricetina (10, 100 e 1000nM) evidenciaram maior (P<0,05) BCF, quando comparadas ao grupo controle. O grupo tratado com miricetina 1000nM apresentou maior percentual (P<0,05) de células com peroxidação lipídica, quando comparado ao grupo controle. Em conclusão, a suplementação do diluidor de criopreservação de sêmen ovino com 10 e 100nM de miricetina afeta a cinética espermática sem provocar alterações na estrutura geral do gameta, enquanto 1000nM de miricetina provoca mudanças na cinética associadas à danos peroxidativos.(AU)

The aim of this study was to evaluate the effect of the supplementation of ram semen frozen with extender with the flavonoid myricetin against damage to sperm. Eight pools of semen obtained from four ram breeders, were frozen with different concentrations of myicetin (0, 1, 10, 100 and 1000nM). After thawing, the semen was evaluated for spermatic kinetics, plasma and acrosome membrane integrity, mitochondrial membrane potential, intracellular ROS levels, lipid peroxidation, and membrane stability. Samples treated with 10nM myricetin preserved a lower percentage of rapid cells (P≤0.05) when compared to the 1000nM myricetin group. Samples from the control group presented higher (P≤0.05) VAP than 10nM group of myricetin, while cryopreserved samples with myicetin (10, 100 and 1000nM) showed greater (P<0.05) BCF, when compared to control group. The group treated with 1000nM myricetin had a higher percentage (P<0.05) of cells with lipid peroxidation, when compared to the control group. In conclusion, supplementation of ram semen cryopreservation extender with 10 and 100nM myricetin affects sperm kinetics, without causing changes in the overall structure of the gamete, while 1000nM myricetin causes changes in the kinetics associated with peroxidative damage.(AU)

Baicalein alleviates tubular-interstitial nephritis in vivo and in vitro by down-regulating NF-κB and MAPK pathways

Tubular-interstitial nephritis (TIN) is characterized by tubular cell damage and inflammatory lesions of kidneys. Baicalein (BAI) is a flavonoid compound found in the roots of Scutellaria baicalensis Georgi. The present study was undertaken to explore the anti-inflammatory and anti-oxidative effects of BAI on TIN patients and a lipopolysaccharide (LPS)-induced TIN cell model. The expression levels of interleukin-6 (IL-6), IL-10, and tumor necrosis factor α in serum samples of TIN patients and culture supernatants of renal proximal tubular epithelial cells (RPTECs) were evaluated using enzyme-linked immunosorbent assay. Creatinine clearance was calculated using the Cockcroft-Gault equation. Activities of malondialdehyde, superoxide dismutase, and glutathione peroxidase were also determined. Viability and apoptosis of RPTECs were measured using MTT assay and Guava Nexin assay, respectively. qRT-PCR was performed to determine the expressions of Bax, Bcl-2, nuclear factor kappa B (IκBα), and p65. Protein levels of Bax, Bcl-2, IκBα, p65, c-Jun N-terminal kinase, extracellular regulated protein kinases, and p38 were analyzed using western blotting. We found that BAI reduced inflammation and oxidative stress in vivo and in vitro. Moreover, BAI alleviated the LPS-induced RPTECs viability inhibition and apoptosis enhancement, as well as nuclear factor kappa B (NF-κB), and mitogen-activated protein kinase (MAPK) activation. Phorbol ester, an activator of NF-κB, attenuated the effects of BAI on LPS-induced inflammatory cytokine expressions in RPTECs. In conclusion, BAI had anti-inflammatory and anti-oxidative effects on TIN patients and LPS-induced RPTECs by down-regulating NF-κB and MAPK pathways.

Modificaciones en el nivel de anión superóxido en leche materna, según la ingesta de flavonoides y carotenoides / Modifications of the superoxide anion level in breast milk by the intake of flavonoids and carotenoids

Resumen: Objetivo: Asociar la ingesta de flavonoides y carotenoides con el nivel en leche materna del anión superóxido, como marcador de estrés oxidativo. Material y métodos: Durante el periodo 2013-2015 se estudió a 100 mujeres lactantes de Córdoba (Argentina), dentro los primeros seis meses posparto; se evaluaron sus datos sanitarios, ingesta alimentaria y nivel lácteo del anión con regresión logística múltiple. Resultados: La ingesta de flavonoides, carotenoides provitamínicos y carotenoides no provitaminas fue de 72 (61) mg/día, 1 813 (1657) µg/día y 5 427 (3664) µg/día, respectivamente. El anión se asoció con la ingesta de flavanoles (RM=1.081; IC95 1.001-1.167) y flavanonas (RM=1.025; IC95 1.001-1.048). No se observó este efecto con otros flavonoides ni con los carotenoides. Conclusiones: La ingesta de flavanoles y flavanonas aumenta el riesgo de oxidación láctea, lo cual es relevante para realizar recomendaciones dietéticas.

Abstract: Objective: To associate the intake of flavonoids and carotenoids with the breast milk level of superoxide anion, as an oxidative stress marker. Materials and methods: 100 women from Cordoba (Argentina), who breastfed within the first postpartum 6 months, were studied during the 2013-2015 period, by evaluating their sanitary data, food intake and anion level in milk with multiple logistic regression. Results: The intake of flavonoids, provitamin A carotenoids and non-provitamin carotenoids was 72 (61) mg/d, 1813 (1 657) µg/d y 5427 (3 664) µg/d, respectively. The anion was associated with the intake of flavanols (OR=1.081; CI95 1.001-1.167) y flavanones (OR=1.025; CI95 1.001-1.048). This effect was not seen with other flavonoids and carotenoids. Conclusions: Intake of flavanols and flavanones increases milk oxidation risk, which is relevant to develop diet recommendations.

Naringenin regulates production of matrix metalloproteinases in the knee-joint and primary cultured articular chondrocytes and alleviates pain in rat osteoarthritis model

Inflammation of cartilage is a primary symptom for knee-joint osteoarthritis. Matrix metalloproteinases (MMPs) are known to play an important role in the articular cartilage destruction related to osteoarthritis. Naringenin is a plant-derived flavonoid known for its anti-inflammatory properties. We studied the effect of naringenin on the transcriptional expression, secretion and enzymatic activity of MMP-3 in vivo in the murine monosodium iodoacetate (MIA) osteoarthritis model. The assessment of pain behavior was also performed in the MIA rats. The destruction of knee-joint tissues was analyzed microscopically. Moreover, the effect of naringenin was also studied in vitro in IL-1β activated articular chondrocytes. The transcriptional expression of MMP-3, MMP-1, MMP-13, thrombospondin motifs (ADAMTS-4) and ADAMTS-5 was also studied in primary cultured chondrocytes of rats. Naringenin caused significant reduction in pain behavior and showed marked improvement in the tissue morphology of MIA rats. Moreover, a significant inhibition of MMP-3 expression in MIA rats was observed upon treatment with naringenin. In the in vitro tests, naringenin caused a significant reduction in the transcriptional expression, secretion and enzymatic activity of the studied degradative enzymes. The NF-κB pathway was also found to be inhibited upon treatment with naringenin in vitro. Overall, the study suggests that naringenin alleviated pain and regulated the production of matrix-metalloproteinases via regulation of NF-κB pathway. Thus, naringenin could be a potent therapeutic option for the treatment of osteoarthritis.

Kinetic study of the quenching of singlet oxygen by naringin isolated from peels of the fruit of bitter orange (Citrus aurantium I)

Introduction: antioxidant activity is the capacity of a substance to inhibit oxidative degradation, mainly through its ability to react with both radical and non-radical species (e.g. singlet oxygen). Interest by scientific communities in the study of the antioxidant capacity of natural compounds has increased in recent years, due to their possible applications in the pharmaceutical, cosmetic and food industries. Objective: estimate the antioxidant capacity of naringin against singlet oxygen using the rubrene method. Methods: naringin was isolated from peels of the fruit of bitter orange (Citrus aurantium) and characterized using several spectroscopic techniques (UV-Vis and FTIR). The global rate constant for the reaction of 1O2 with naringin was determined with the Stern-Volmer plot derived from a stationary kinetic state based on the competition reaction with rubrene. Results: results showed that naringin acted as singlet oxygen quenching agent with a global rate constant of 2.1 x 107 M-1s-1 (derived from the linear relationship of Stern-Volmer). Conclusion: the kinetic study conducted suggests that naringin could be used as a singlet oxygen quenching agent in biological systems to protect them from oxidative damage(AU)

Introducción: la actividad antioxidante es la capacidad de una sustancia para inhibir la degradación oxidativa y actúa principalmente a través de su capacidad para reaccionar con las especies de radicales y no radicales (por ejemplo, oxígeno singulete). En los últimos años, se han incrementado el interés de las comunidades científicas en el estudio de la capacidad antioxidante de los compuestos naturales debido a sus posibles aplicaciones en la industria farmacéutica, cosmética y alimentaria. Objetivo: estimar la capacidad antioxidante de la naringina contra el oxígeno singulete usando el método de rubreno. Métodos: la naringina se aisló de cáscaras del fruto de la naranja agria (Citrus aurantium) y se caracterizó por algunas técnicas espectroscópicas (UV-Vis y FT-IR). La constante de velocidad global para la reacción de 1O2 con la naringina se determinó por medio del gráfico de Stern-Volmer derivado de una cinética en estado estacionario basada en la reacción de competición con el rubreno. Resultados: los resultados mostraron que la naringina actuó como un quenching del oxígeno singulete con una constante de velocidad global de 2.1 x 10 7 M-1s-1 (derivado de la relación lineal de Stern-Volmer). Conclusión: el estudio cinético sugiere que la naringina se podría utilizar como un quenching del oxígeno singulete en sistemas biológicos y protegerlos del daño oxidativo(AU)

Direct actions of naringin on rat cardiac and vascular smooth muscle / Acciones directas de la naringina sobre los músculos cardíaco y liso vascular de rata

Naringin (NRG) is a flavanone glycoside present in grapefruit juice. Its biological activity has been only partially characterized and little is known about its potential effects in the cardiovascular system. We studied the effects of NRG on the electrical and contractile activities of isolated rat hearts and on the contraction of rat abdominal aortic rings. NRG exerted a negative inotropic action in hearts with an IC50 of 72.5 umol/L but its effects on heart rate and surface electrogram were minimal. Surprisingly, NRG (10-100 umol/L) was able to increase tension in aortic rings contracted by isotonic KCl or phenylephrine. This action of NRG was also evident in aortic rings in basal (resting) conditions but it was absent when resting aortic rings were previously perfused with ryanodine (30 umol/L). Our results indicate that NRG has direct actions on cardiac and vascular smooth muscles that should be taken into account when considering this molecule either as a dietetic supplement or as a template to develop therapeutic agents for human diseases.

La naringina (NRG) es un glicósido de flavanona que se encuentra presente en el jugo de toronja. Su actividad biológica ha sido solo parcialmente caracterizada y poco se conoce acerca de sus efectos sobre el sistema cardiovascular. En la presente investigación estudiamos los efectos de la NRG sobre las actividades eléctrica y contráctil de corazones aislados de rata y sobre la contracción de anillos de aorta abdominal de rata. La NRG ejerció una acción inotropo-negativa en corazones con una IC50 de 72.5 umol/L pero sus efectos sobre la frecuencia cardíaca y el electrograma de superficie fueron mínimos. Sorpresivamente, la NRG (10-100 umol/L) incrementó la tensión en anillos de aorta contraídos por KCl isotónico o fenilefrina. Esta acción de la NRG ocurrió también en anillos de aorta en condiciones basales (en reposo) pero estuvo ausente cuando los anillos de aorta fueron previamente perfundidos con ryanodina (30 umol/L). Nuestros resultados indican que la NRG tiene acciones directas sobre los músculos cardíaco y liso vascular que deben tenerse en cuenta al considerar esta molécula como suplemento dietético o como plantilla para el desarrollo de agentes terapéuticos para el tratamiento de enfermedades en humanos.

Antioxidant and antibacterial activity of extracts, fractions and isolated substances from the flowers of Acacia podalyriifolia A. Cunn. ex G. Don

The extracts and fractions from the flowers of A. podalyriifolia were analyzed previously for antibacterial activity using diffusion in disk, Antioxidant properties were evaluated by determining radical scavenging power (DPPH test) and total phenol content was measured (Folin method). The present study describes the in vitro antibacterial (determining minimum inhibitory concentration) and antioxidant activities (by thiobarbituric acid reactive species - TBARS method) for the ethanol extract, dichloromethane and ethyl acetate fractions and two flavanones (naringenin and 5-β-D-glycosyl-naringenin) isolated from the flowers of Acacia podalyriifolia A. Cunn. ex G. Don. The flavanones naringenin and 5-β-D-glycosyl-naringenin had not previously been obtained from this species. The most effective antibacterial activity was observed in the ethyl acetate fraction (MIC=0.25 mg mL-1 against Staphylococcus aureus ATCC 6538, MIC = 0.125 mg mL-1 against Staphylococcus epidermidis ATCC 12229, MIC=0.5 mg mL-1 against Streptococcus pyogenes ATCC 19615, Klebsiella pneumoniae ATCC 13883 and Proteus mirabilis ATCC 43071). The evaluated samples showed antioxidant activity on the TBARS test, especially for ethanol extract (1000 ppm), which was the most active (29.43% ± 0.65) followed by ethyl acetate fraction (1000 ppm, 24.84% ± 1,28), both demonstrating higher activity than that presented by ascorbic acid (1000 ppm, 21.73% ± 1.77), although lower than the BHT (1000 ppm 35.15% ± 3.42), both reference compounds. Naringenin and 5-β-D-glycosyl-naringenin demonstrated antioxidant action, but only naringenin inhibited the growth of gram-positive and gram-negative bacteria.

Os extratos e frações de Acacia podalyriifolia foram analisados previamente para a atividade antibacteriana através da difusão em disco e as propriedades antioxidantes foram verificadas pela determinação da capacidade removedora do radical livre DPPH e pela mensuração do conteúdo de fenólicos totais (Método de Folin). O presente estudo descreve as atividades antibacteriana (determinação da concentração inibitória mínima) e antioxidante (espécies reativas do ácido tiobarbitúrico - teste TBARS) para o extrato etanólico e as frações diclorometano e acetato de etila e para duas flavanonas (naringenina e 5-β-D-glicosil-naringenina) isoladas das flores de Acacia podalyriifolia A. Cunn. ex G. Don. As flavanonas naringenina e 5-β-D-glicosil-naringenina ainda não haviam sido obtidas desta espécie. A atividade antibacteriana mais efetiva foi observada com a fração acetato de etila (CIM=0,25 mg/mL contra Staphylococcus aureus ATCC 6538; CIM=0,125 mg/mL, contra Staphylococcus epidermidis ATCC 12229; CIM=0,5 mg/mL contra Streptococcus pyogenes ATCC 19615, Klebsiella pneumoniae ATCC 13883 e Proteus mirabilis ATCC 43071). As amostras avaliadas demonstraram atividade pelo teste TBARS, especialmente o extrato etanólico (1000 ppm), que foi o mais ativo (29,43% ± 0.65), seguido pela fração acetato de etila (1000 ppm, 24,84% ± 1,28), ambos demonstrando atividade mais elevada que a apresentada pelo ácido ascórbico (1000 ppm, 21,73% ± 1,77), ainda que menor que a do BHT (1000 ppm, 35,15% ± 3,42), ambas substâncias de referência. Naringenina e 5-β-D-glicosil-naringenina demonstraram ação antioxidante, porém somente a naringenina inibiu o crescimento de bactérias gram-positivas e gram-negativas.

El chocolate, un placer saludable / Chocolate, a healthy pleasure

El cacao, que se obtiene de la almendra del árbol del cacao, fue utilizado durante cientos de años por los indígenas sudamericanos en la preparación de una bebida amarga, que los europeos modificaron en su preparación y composición, hasta originar lo que hoy se conoce como el chocolate, en sus variedades negro (u oscuro), con leche, y blanco. De ellos el más interesante es el chocolate negro, debido a su alto contenido de los flavanoles epicatequina, catequina y procianidinas. Se ha demostrado que estos flavanoles ejercen poderosos efectos antioxidantes al inhibir la oxidación de las LDL, además de producir una disminución de la agregación plaquetaria y de la presión arterial. El chocolate negro contiene una alta cantidad de flavanoles, por lo cual su consumo se asocia a una protección de la salud cardiovascular y a otras patologías. El efecto antioxidante y cardioprotector del chocolate ha sido demostrado en numerosos protocolos experimentales y estudios clínicos y epidemiológicos. El presente trabajo, actualiza el conocimiento sobre el chocolate y sus beneficios en la salud.

Cocoa, which is obtained from the beans of the cocoa tree, was used hundred of years ago by the South America indigenous population for the preparation of a strong and bitter beverage. Later, the Europeans modified the preparation and composition of this beverage to develop what we now know as chocolate, presently produced as black (or dark) chocolate, milk chocolate, or white chocolate. From these products, black chocolate is the most interesting, because of its high content of the flavanols epicatechin, catechin and procyanidins. These flavanols exhibit strong antioxidant activity inhibiting LDL oxidation, platelet adhesion and reducing arterial pressure. Consumption of black chocolate containing a high amount of flavanols is associated with beneficial effects in cardiovascular health and other diseases were oxidative process are involved, demonstrated in a number of experimental, clinical, and epidemiological studies. The present review summarizes the state of the art about the health benefits of chocolate consumption.