Browsing by Subject "Flavonoids"
Now showing 1 - 13 of 13
Results Per Page
Sort Options
- PublicationOpen AccessBeneficial Effects of Different Flavonoids on Vascular and Renal Function in L-NAME Hypertensive Rats(MDPI, 2018-04-13) Paredes, María Dolores; Romecín, Paola; Atucha, Noemí. M.; O'Valle, Francisco; Castillo, Julián; Ortiz, M. Clara; García-Estañ, Joaquín; FisiologíaBackground: we have evaluated the antihypertensive effect of several flavonoid extracts in a rat model of arterial hypertension caused by chronic administration (6 weeks) of the nitric oxide synthesis inhibitor, L-NAME. Methods: Sprague Dawley rats received L-NAME alone or L-NAME plus flavonoid-rich vegetal extracts (Lemon, Grapefruit + Bitter Orange, and Cocoa) or purified flavonoids (Apigenin and Diosmin) for 6 weeks. Results: L-NAME treatment resulted in a marked elevation of blood pressure, and treatment with Apigenin, Lemon Extract, and Grapefruit + Bitter Orange extracts significantly reduced the elevated blood pressure of these animals. Apigenin and some of these flavonoids also ameliorated nitric oxide-dependent and -independent aortic vasodilation and elevated nitrite urinary excretion. End-organ abnormalities such as cardiac infarcts, hyaline arteriopathy and fibrinoid necrosis in coronary arteries and aorta were improved by these treatments, reducing the end-organ vascular damage. Conclusions: the flavonoids included in this study, specially apigenin, may be used as functional food ingredients with potential therapeutic benefit in arterial hypertension
- PublicationOpen AccessBinding of Natural and Synthetic Polyphenols to Human Dihydrofolate Reductase(MDPI, 2009-12-18) Sáez Ayala, Magalí; Chazarra Parres, Soledad; Cabezas Herrera, Juan; Rodríguez López, José Neptuno; Sánchez del Campo Ferrer, Luis; Bioquímica y Biología Molecular ADihydrofolate reductase (DHFR) is the subject of intensive investigation since it appears to be the primary target enzyme for antifolate drugs. Fluorescence quenching experiments show that the ester bond-containing tea polyphenols (-)-epigallocatechin gallate (EGCG) and (-)-epicatechin gallate (ECG) are potent inhibitors of DHFR with dissociation constants (K-D) of 0.9 and 1.8 mu M, respectively, while polyphenols lacking the ester bound gallate moiety [e.g., (-)-epigallocatechin (EGC) and (-)-epicatechin (EC)] did not bind to this enzyme. To avoid stability and bioavailability problems associated with tea catechins we synthesized a methylated derivative of ECG (3-O-(3,4,5-trimethoxybenzoyl)(-)-epicatechin; TMECG), which effectively binds to DHFR (K-D = 2.1 mu M). In alkaline solution, TMECG generates a stable quinone methide product that strongly binds to the enzyme with a K-D of 8.2 nM. Quercetin glucuronides also bind to DHFR but its effective binding was highly dependent of the sugar residue, with quercetin-3-xyloside being the stronger inhibitor of the enzyme with a K-D of 0.6 mu M. The finding that natural polyphenols are good inhibitors of human DHFR could explain the epidemiological data on their prophylactic effects for certain forms of cancer and open a possibility for the use of natural and synthetic polyphenols in cancer chemotherapy.
- PublicationOpen AccessFlavonoid profile of Lupinus mexicanus germinated seed extract and evaluation of its neuroprotective effect(F. Hernández y Juan F. Madrid. Universidad de Murcia: Departamento de Biología Celular e Histología, 2014) Uribe-Gómez, José de Jesús; Zamora-Natera, Juan Francisco; Bañuelos-Pineda, Jacinto; Kachlicki, Piotr; Stobieck, Maciej; García-López, Pedro MacedonioThe aim of this study was to determine the flavonoid profile of Lupinus mexicanus germinated seed extract (PE) and to evaluate its effect as a phytoestrogen on the morphometric parameters of CA3 hippocampal neurons of ovariectomized rats (OVX). L. mexicanus seeds, germinated for 48 h, were homogenized and macerated using an 80% ethanol solution. The extract was analyzed by HPLC/MS-MS. Thirty young Wistar strain female rats (200±10 g) were randomly distributed into four groups: sham operated (S) treated with dimethyl sulfoxide (vehicle); ovariectomized and treated with 1250 µg of PE extract (OVX-PE); ovariectomized and treated with 5 µg estradiol benzoate (OVX-EB); and ovariectomized and vehicle treated (OVX). All substances were injected subcutaneously daily for 28 days. On day 29, the animals were sacrificed, perfused, and fixed to obtain the brains for histological processing. Each brain was cut and stained with hematoxylin and eosin. The thickness of the stratum oriens (SO), the nuclear diameter, and the neuronal density were measured in the hippocampus CA3 area. Nine different flavonoids and one non-identified compound were detected. The histological analysis demonstrated that the thickness of the SO was higher in the OVX-EB and S groups than in the OVX-PE and OVX groups (p<0.05); in addition, the nuclear diameters of the neurons in the OVX-EB and S groups were higher compared with the other groups (p<0.05). The OVX group had the highest cellular density among groups (p<0.05). Based on our results, the PE obtained did not have beneficial effects on CA3 hippocampal neurons.
- PublicationOpen AccessFlavonoids in Kidney Health and Disease(Frontiers, 2018-04-24) Vargas, Félix; Romecín, Paola; Wangesteen, Rosemary; Atucha, Noemí M.; García-Estañ, Joaquín; García-Guillén, Ana I.; Vargas-Tendero, Pablo; Paredes, M. Dolores; FisiologíaThis review summarizes the latest advances in knowledge on the effects of flavonoids on renal function in health and disease. Flavonoids have antihypertensive, antidiabetic, and antiinflammatory effects, among other therapeutic activities. Many of them also exert renoprotective actions that may be of interest in diseases such as glomerulonephritis, diabetic nephropathy, and chemically-induced kidney insufficiency. They affect several renal factors that promote diuresis and natriuresis, which may contribute to their well-known antihypertensive effect. Flavonoids prevent or attenuate the renal injury associated with arterial hypertension, both by decreasing blood pressure and by acting directly on the renal parenchyma. These outcomes derive from their interference with multiple signaling pathways known to produce renal injury and are independent of their blood pressure-lowering effects. Oral administration of flavonoids prevents or ameliorates adverse effects on the kidney of elevated fructose consumption, high fat diet, and types I and 2 diabetes. These compounds attenuate the hyperglycemia-disrupted renal endothelial barrier function, urinary microalbumin excretion, and glomerular hyperfiltration that results from a reduction of podocyte injury, a determinant factor for albuminuria in diabetic nephropathy. Several flavonoids have shown renal protective effects against many nephrotoxic agents that frequently cause acute kidney injury (AKI) or chronic kidney disease (CKD), such as LPS, gentamycin, alcohol, nicotine, lead or cadmium. Flavonoids also improve cisplatin- or methotrexate-induced renal damage, demonstrating important actions in chemotherapy, anticancer and renoprotective effects. A beneficial prophylactic effect of flavonoids has been also observed against AKI induced by surgical procedures such as ischemia/reperfusion (I/R) or cardiopulmonary bypass. In several murine models of CKD, impaired kidney function was significantly improved by the administration of flavonoids from different sources, alone or in combination with stem cells. In humans, cocoa flavanols were found to have vasculoprotective effects in patients on hemodialysis. Moreover, flavonoids develop antitumor activity against renal carcinoma cells with no toxic effects on normal cells, suggesting a potential therapeutic role in patients with renal carcinoma.
- PublicationRestrictedFlavonoids inhibit platelet function through binding to the thromboxane A2 receptor(Elsevier, 2005) Lozano Almela, María Luisa; Castillo, J.; Benavente-García, O.; Vicente, Vincente; Rivera Pozo, José; Guerrero López, José Antonio; Medicina Interna; Facultad de MedicinaBackground: Dietary flavonoids are known for their antiplatelet activity resulting in cardiovascular protection, although the specific mechanisms by which this inhibition occurs has not been fully established. Objective: The aim of this study was to Investigate the interaction of nine flavonoids representative of various chemical classes, with platelet responses dependent on thromboxane A2 (TxA2) generation and on receptor antagonism, and to analyze the structural requirements for such effects. Methods: The effect of several types of flavonoids on platelet aggregation, serotonin release, andTxA2generationwasinvestigated. Competitive radioligand binding assays were used to screen for affinity of these compounds to TxA2 receptors. Results: Flavones (apigeninand luteolin) and isoflavones (genistein) abrogated arachidonic acid and collagen-induced platelet responses, such as aggregation and secretion, with a less substantial effect on TxA2 synthesis. These compounds were identified as specific ligands of the TxA2 receptor in the lmol L)1 range, this effect accounting for antiplatelet effects related to stimulation with those agonists. Tight binding of flavonoids to the human TxA2 receptor relies on structural features such as the presence of the double bond in C2–C3, and a keto group in C4. Conclusions: The inhibition by specific flavonoids of in vitro platelet responses induced by collagen or arachidonic acid seems to be related, to a great extent, to their ability to compete for binding to the TxA2receptor. Therefore, antagonism of this TxA2 receptor may represent an additional mechanism for the inhibitory effect of these compounds in platelet function.
- PublicationOpen AccessFlavonoids’ effects on Caenorhabditis elegans’ longevity, fat accumulation, stress resistance and gene modulation involve mTOR, SKN-1 and DAF-16(MDPI, 2021-03-12) Guerrero Rubio, María Alejandra; Hernández García, Samanta; Gandía Herrero, Fernando; García Carmona, Francisco; Bioquímica y Biología Molecular "A"Flavonoids are potential nutraceutical compounds present in diary food. They are considered health-promoting compounds and promising drugs for different diseases, such as neurological and inflammatory diseases, diabetes and cancer. Therefore, toxicological and mechanistic studies should be done to assert the biological effects and identify the molecular targets of these compounds. In this work we describe the effects of six structurally-related flavonoids—baicalein, chrysin, scutellarein, 6-hydroxyflavone, 6,7-dihydroxyflavone and 7,8-dihydroxyflavone—on Caenorhabditis elegans’lifespan and stress resistance. The results showed that chrysin, 6-hydroxyflavone and baicalein prolonged C. elegans’ lifespan by up to 8.5%, 11.8% and 18.6%, respectively. The lifespan extensions caused by these flavonoids are dependent on different signaling pathways. The results suggested that chrysin’s effects are dependent on the insulin signaling pathway via DAF-16/FOXO. Baicalein and 6-hydroxyflavone’s effects are dependent on the SKN-1/Nfr2 pathway. In addition, microarray analysis showed that baicalein downregulates important age-related genes, such as mTOR and PARP.
- PublicationOpen AccessInitial growth and production of secondary metabolites in Basella alba leaves cultivated in a sandy textured soil with addition of organic and organo-mineral substrate(Universidad de Murcia. Servicio de publicaciones, 2022) Pina, José Carlos; Morbeck-de-Oliveira, Ademir Kleber; Matias, RosemaryCrecimiento inicial y producción de metabolitos secundarios en hojas de Basella alba cultivadas en un suelo de textura arenosa con adición de sustrato orgánico y organomineral La especie Basella alba se conoce popularmente como bertalha india y se consume ampliamente en forma de ensaladas, por ejemplo. El objetivo de este estudio fue evaluar las etapas iniciales de crecimiento y la producción de metabolitos secundarios en diferentes sustratos. Transcurridos 90 días desde el inicio de la plantación (pleno sol), en suelo arenoso mezclado con diferentes sustratos, se determinó el efecto de los sustratos sobre el crecimiento y producción de metabolitos secundarios en las hojas. Los resultados indicaron que el tratamiento con la adición de 70% de vermicompost indujo el mayor crecimiento y la mejor concentración de compuestos fenólicos y flavonoides. Sin embargo, la mayoría de los tratamientos dieron como resultado la producción de heterósidos cardiotónicos, que pueden causar problemas de salud.
- PublicationOpen AccessModerate Effect of Flavonoids on Vascular and Renal Function in Spontaneously Hypertensive Rats(MDPI, 2018-08-16) Paredes, María Dolores; Romecín, Paola; Atucha, Noemí M.; O'Valle, Francisco; Castillo, Julián; Ortiz, M. Clara; García-Estañ, Joaquín; FisiologíaMany studies have shown that flavonoids are effective as antihypertensive drugs in arterial hypertension. In the present work, we have analyzed the effects of some flavonoid extracts in the spontaneous hypertensive rat model (SHR). An important feature of this study is that we have used a low dose, far from those that are usually applied in human therapy or experimental animals, a dose that responded to the criterion of a potential future commercial use in human subjects. Treatments were carried out for 6 and 12 weeks in two groups of SHR rats, which received apigenin, lemon extract, grapefruit + bitter orange (GBO) extracts, and cocoa extract. Captopril was used as a positive control in the SHR group treated for 6 weeks (SHR6) and Diosmin was used as the industry reference in the SHR group treated for 12 weeks (SHR12). Captopril and GBO extracts lowered the high arterial pressure of the SHR6 animals, but none of the extracts were effective in the SHR12 group. Apigenin, lemon extract (LE), GBO, and captopril also improved aortic vascular relaxation and increased plasma and urinary excretion of nitrites, but only in the SHR6 group. Kidney and urinary thiobarbituric acid reactive substances (TBARS) were also significantly reduced by GBO in the SHR6 rats. Apigenin also improved vascular relaxation in the SHR12 group and all the flavonoids studied reduced urinary thiobarbituric acid reactive substances (TBARS) excretion and proteinuria. Vascular abnormalities, such as lumen/wall ratio in heart arteries and thoracic aorta, were moderately improved by these treatments in the SHR6 group. In conclusion, the flavonoid-rich extracts included in this study, especially apigenin, LE and GBO improved vascular vasodilatory function of young adult SHRs but only the GBO-treated rats benefited from a reduction in blood pressure. These extracts may be used as functional food ingredients with a moderate therapeutic benefit, especially in the early phases of arterial hypertension
- PublicationOpen AccessNeoastilbin ameliorates sepsis-induced liver and kidney injury by blocking the TLR4/NF-κB pathway(Universidad de Murcia. Departamento de Biología Celular e Histología, 2024) Xu, Ruiming; Wang, Dawei; Shao, Zhengyi; Li, Xiangbo; Cao, QiumeiSepsis frequently causes systemic inflammatory response syndrome and multiple organ failure in patients. Neoastilbin (NAS) is a flavonoid that plays vital functions in inflammation. This work aims to investigate the protective effects of NAS against sepsisinduced liver and kidney injury and elucidate its underlying mechanisms. The mouse model was established using cecal ligation puncture (CLP) induction. NAS was given to mice by gavage for 7 consecutive days before surgery. Liver and kidney function, oxidative stress, and inflammatory factors in serum or tissues were examined by ELISA or related kits. The expression of relevant proteins was assessed by Western blot. Hematoxylin and eosin and/or periodic acid-Schiff staining revealed that NAS ameliorated the pathological damage in liver and kidney tissues of CLPinduced mice. NAS improved liver and kidney functions, as evidenced by elevated levels of blood urea nitrogen, Creatinine, ALT, and AST in the serum of septic mice. TUNEL assay and the expression of Bcl-2 and Bax showed that NAS dramatically reduced apoptosis in liver and renal tissues. NAS treatment lowered the levels of myeloperoxidase and malondialdehyde, while elevated the superoxide dismutase content in liver and kidney tissues of CLPinduced mice. The levels of inflammatory cytokines (IL6, TNF-α, and IL-1β) in the serum and both tissues of CLP-injured mice were markedly decreased by NAS. Mechanically, NAS downregulated TLR4 expression and inhibited NF-κB activation, and overexpression of TLR4 reversed the protective effects of NAS against liver and kidney injury. Collectively, NAS attenuated CLP-induced apoptosis, oxidative stress, inflammation, and dysfunction in the liver and kidney by restraining the TLR4/NF-κB pathway.
- PublicationEmbargoPhenolic profiling and in vitro bioactivities of three medicinal Bryophyllum plants(Elsevier, 2021-01-14) Ayuso, Manuel; Lozano-Milo, Eva; Pereira, Carla; Dias, María Inés; Calhelha, Ricardo C.; Sokovic, Marina; Ferreira, Isabel C.F.R.; Barros, Lillian; Gallego, Pedro P.; Ivanov, Marija; García Pérez, Pascual; Tecnología de Alimentos, Nutrición y Bromatología
- PublicationOpen AccessPolyphenol extracts from sage (Salvia lavandulifolia Vahl) by-products as natural antioxidants for pasteurised chilled yoghurt sauce(MDPI, 2023-02-03) Cedeño Pinos, Cristina; Jiménez Monreal, Antonia María; Quílez, María; Bañón, Sancho; Tecnología de Alimentos, Nutrición y BromatologíaSage by-product extracts (SE) are a valuable source of phenolic acids and flavonoids for food applications. The objective was to test two SE as antioxidants in pasteurised chilled yoghurt sauces against oxidation. Two SE of different polyphenol total content and profile were selected: SE38 (37.6 mg/g) and SE70 (69.8 mg/g), with salvianic and rosmarinic acid as the main polyphenols, respectively. Four experimental low-fat yoghurt sauces were formulated: untreated; SE70/2 (0.16 g/kg); SE38 (0.3 g/kg); and SE70 (0.3 g/kg). The stability of phenolic acids, microbiological quality (mesophilic bacteria, moulds and yeasts, and L. monocytogenes), and oxidative stability (lipids, colour, and pH) were studied in the sauces after pasteurisation at 70 C for 30 min (day 0) and stored by refrigeration (day 42). Pasteurisation and further chilling ensured the microbiological quality and inhibition of microbial growth could not be evidenced, although SE70 showed some antimicrobial potential. Both SE showed good properties as antioxidants for yoghurt sauces. This finding was based on two results: (i) their main polyphenols, salvianic and rosmarinic acids, resisted to mild pasteurisation and remained quite stable during shelf life; and (ii) SE improved radical scavenging capacity, delayed primary and secondary lipid oxidation, and increased colour stability, contributing to sauce stabilisation. SE38 had a better antioxidant profile than SE70; therefore, the selection criteria for SE should be based on both quantity and type of polyphenols. Due to their stability and antioxidant properties, sage polyphenols can be used as natural antioxidants for clean-label yoghurt sauces.
- PublicationRestrictedThe flavonoid apigenin delays forgetting of passive avoidance conditioning in rats(SAGE Publications, 2013-11-27) Caballero Bleda, María; Benavente-García, Obdulio; Castillo, Julián; Popovic Popovic, Miroljub; Research Institute of Aging, University of Murcia,; Research & Development Department of Nutrafur S.A., Alcantarilla (Murcia),The present experiments were performed to study the effect of the flavonoid apigenin (20 mg/kg intraperitoneally (i.p.), 1 h before acquisition), on 24 h retention performance and forgetting of a step-through passive avoidance task, in young male Wistar rats. There were no differences between saline- and apigenin-treated groups in the 24 h retention trial. Furthermore, apigenin did not prevent the amnesia induced by scopolamine (1mg/kg, i.p., 30 min before the acquisition). The saline- and apigenin-treated rats that did not step through into the dark compartment during the cut-off time (540 s) were retested weekly for up to eight weeks. In the saline treated group, the first significant decline in passive avoidance response was observed at four weeks, and complete memory loss was found five weeks after the acquisition of the passive avoidance task. At the end of the experimental period, 60% of the animals treated with apigenin still did not step through. These data suggest that 1) apigenin delays the long-term forgetting but did not modulate the 24 h retention of fear memory and 2) the obtained beneficial effect of apigenin on the passive avoidance conditioning is mediated by mechanisms that do not implicate its action on the muscarinic cholinergic system.
- PublicationRestrictedThe inhibitory effect of flavonoids and their gut-derived metabolites on the replication of Chlamydia abortus in the AH-1 ovine trophoblast cell line.(Elsevier Ltd., 2019-10-15) Del Río, Laura; Salinas, Jesús; García-Conesa, María Teresa; Buendía Marín, Antonio Julián; Sanidad Animal; Anatomía y Anatomía Patológica ComparadasThe obligate intracellular bacterium Chlamydia abortus causes abortion and constitutes a worldwide threat for livestock. Plant-derived flavonoids have antimicrobial effects against veterinary and human pathogens and may be of help in the fight against C. abortus. The anti-infective efficacy against C. abortus of the flavonoids apigenin and naringenin, and of four of their derived metabolites was explored using an in vitro model of ovine trophoblast cells. Overall, the anti-infective effectiveness was apigenin > naringenin > benzoic acid > 3-(4- hydroxyphenyl) propionic acid~4-hydroxyphenyl acetic acid~4-hydroxybenzoic. At the lowest concentration tested (10 μM), apigenin, naringenin and benzoic acid inhibited the formation of C. abortus inclusions by 80%, 67%, and 39%, respectively. The cytotoxicity and anti-proliferative effects on the trophoblast host cells also differed greatly between the tested compounds. Our findings suggest that flavonoids may be of therapeutic value against C. abortus infection but metabolic conversion has a substantial and variable effect on their anti-chlamydial activity. Our results also support the notion that the mechanisms of anti-infective action may involve combined effects of the compounds against the host cells and the bacteria.