RESUMEN
BACKGROUND: Diosmetin is a bioflavonoid compound naturally abundant in citrus fruits. It is found to perform a variety of activities, while its antitumor property in osteosarcoma, a malignant tumor with unmet clinical treatment, remained unknown. METHODS: Colony formation assay, cell cycle analysis and apoptosis analysis were conducted respectively to observe the effect of diosmetin on cell proliferation and apoptosis in human osteosarcoma cells. Western blot and immunoprecipitation were used to detect the expression of apoptotic molecules and activation of STAT3/c-Myc pathway in Saos-2 and U2SO cells. RESULTS: Diosmetin significantly inhibited cell proliferation, induced cell cycle arrest at G2/M phase and promoted cell apoptosis in both Saos-2 and U2SO cells. Moreover, Diosmetin downregulated the expression of anti-apoptotic protein Bcl-xL while upregulated the levels of pro-apoptotic proteins including cleaved Caspase-3, cleaved-PARP and Bax. Furthermore, diosmetin dose-dependently inhibited STAT3 phosphorylation, reduced the expression of its downstream protein c-Myc and impeded the interaction between STAT3 molecules. CONCLUSIONS: These results suggest that diosmetin exerts anti-osteosarcoma effects by suppressing cell proliferation and inducing apoptosis via inhibiting the activation of STAT3/c-Myc signaling pathway, which provide the possibility for diosmetin to be a chemotherapeutic candidate for osteosarcoma.
Asunto(s)
Flavonoides , Osteosarcoma , Transducción de Señal/efectos de los fármacos , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Flavonoides/farmacología , Humanos , Osteosarcoma/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-myc , Factor de Transcripción STAT3RESUMEN
UVB radiation-mediated inflammation and the oxidative process involve the transient receptor potential vanilloid 1 (TRPV1) channel activation in neuronal and non-neuronal cells. Once diosmetin has been identified as a novel TRPV1 antagonist, we evaluated the action of diosmetin from the inflammatory [ear oedema, myeloperoxidase (MPO) activity, histological changes, and cytokines levels] and oxidative [nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and SOD activities] parameters in mice exposed to UVB radiation (0.5 j/cm2). We also verified the action of diosmetin on UVB radiation-induced inflammatory parameters after cutaneous nerve fibers denervation by RTX (50 µg/kg s.c.). The topical treatment with the novel TRPV1 antagonist, diosmetin (1%; 15 mg/ear), reduced ear oedema, MPO activity, and MIP-2 and IL-1ß cytokines levels by 82 ± 8%, 59 ± 10%, 40 ± 12%, and 85 ± 9%, respectively. The action of diosmetin on ear oedema and inflammatory cell infiltration was histologically confirmed. Topical diosmetin (1%) also reduced NADPH oxidase activity by 67 ± 10% and reverted SOD activity by 81 ± 13%. After cutaneous nerve fibers denervation using RTX, diosmetin reduced ear oedema, but not the inflammatory cell infiltration in mice exposed to UVB radiation. Diosmetin can be a promising molecule against skin inflammatory disorders as a result of sunburn induced by UVB radiation exposure.
Asunto(s)
Flavonoides/administración & dosificación , Piel/efectos de los fármacos , Piel/efectos de la radiación , Quemadura Solar/tratamiento farmacológico , Canales Catiónicos TRPV/antagonistas & inhibidores , Rayos Ultravioleta/efectos adversos , Animales , Relación Dosis-Respuesta a Droga , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Masculino , Ratones , Piel/metabolismo , Crema para la Piel/administración & dosificación , Quemadura Solar/metabolismo , Canales Catiónicos TRPV/metabolismoRESUMEN
BACKGROUND: Diosmetin is a bioflavonoid compound naturally abundant in citrus fruits. It is found to perform a variety of activities, while its antitumor property in osteosarcoma, a malignant tumor with unmet clinical treatment, remained unknown. METHODS: Colony formation assay, cell cycle analysis and apoptosis analysis were conducted respectively to observe the effect of diosmetin on cell proliferation and apoptosis in human osteosarcoma cells. Western blot and immunoprecipitation were used to detect the expression of apoptotic molecules and activation of STAT3/c-Myc pathway in Saos-2 and U2SO cells. RESULTS: Diosmetin significantly inhibited cell proliferation, induced cell cycle arrest at G2/M phase and promoted cell apoptosis in both Saos-2 and U2SO cells. Moreover, Diosmetin downregulated the expression of anti-apoptotic protein Bcl-xL while upregulated the levels of pro-apoptotic proteins including cleaved Caspase-3, cleaved-PARP and Bax. Furthermore, diosmetin dose-dependently inhibited STAT3 phosphorylation, reduced the expression of its downstream protein c-Myc and impeded the interaction between STAT3 molecules. CONCLUSIONS: These results suggest that diosmetin exerts anti-osteosarcoma effects by suppressing cell proliferation and inducing apoptosis via inhibiting the activation of STAT3/c-Myc signaling pathway, which provide the possibility for diosmetin to be a chemotherapeutic candidate for osteosarcoma.
Asunto(s)
Humanos , Flavonoides/farmacología , Transducción de Señal/efectos de los fármacos , Osteosarcoma/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-myc , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Factor de Transcripción STAT3RESUMEN
"Quelites" are edible plants that are part of the traditional agro-ecosystems in Mexico. These plants, despite their already known nutritional properties, are now considered neglected and underutilized species. With the objective of promoting their reinsertion in the markets and mainly, in daily diets, efforts have been made to study them from multidisciplinary approaches to demonstrate their beneficial properties. To generate evidence of an added health-promoting value that would encourage quelites consumption, in the present work, the anti-Helicobacter pylori activity of three representative quelite species, Anoda cristata (Alache), Cnidoscolus aconitifolius (Chaya), and Crotalaria pumila (Chepil), was tested. H. pylori is considered the etiological agent of gastritis, ulcer, and gastric cancer, and represents a public health problem in Mexico and worldwide. Aqueous (AQ) and dichloromethane-methanol (DM) extracts were obtained from the three species of quelites to investigate their effect on H. pylori growth and on two of its colonization factors (adherence and urease activity). DM extracts from Chaya, Chepil, and Alache exert the best inhibitory effect on bacterial growth, with minimum inhibitory concentrations of 62.5, 125, and 250 µg/mL, respectively. AQ and DM extracts inhibit bacterial adhesion by 30% to 50%. None of them has an effect on urease activity. The two flavonoids present in A. cristata, acacetin and diosmetin, inhibit H. pylori growth by â¼90% with 3.9 µg/mL. These results provide new information about the anti-H. pylori potential of three edible quelites, and give an added value, since their routine consumption may impact on the prevention and/or control of H. pylori-associated diseases.
Asunto(s)
Antibacterianos/farmacología , Crotalaria/química , Euphorbiaceae/química , Infecciones por Helicobacter/microbiología , Helicobacter pylori/efectos de los fármacos , Malvaceae/química , Extractos Vegetales/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Flavonas/análisis , Flavonas/farmacología , Flavonoides/farmacología , Helicobacter pylori/crecimiento & desarrollo , Humanos , México , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Plantas Comestibles/químicaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Some studies refer that the entire plant of Anoda cristata is consumed as food and medicine; in particular for treating diabetes, inflammation, fever, cough, and wounds. The aim of this study was to establish the preclinical efficacy of Anoda cristata as hypoglycemic and/or antihyperglycemic agent using well-known animal models. MATERIALS AND METHODS: The acute toxicity was analyzed by the Lorke method. Acute hypoglycemic as well as oral glucose and sucrose tolerance tests were used to determine the hypoglycemic and antihyperglycemic action of Anoda cristata. Several preparations of the plant, including a mucilage (M), an aqueous (T-AE), a free mucilage aqueous (FM-AE), and an organic (OE) extracts, were tested in healthy and NA-STZ-hyperglycemic mice. Glibenclamide (15mg/kg), acarbose (5mg/kg ) and metformin (200mg/kg) were used as positive controls. The major compounds acacetin (1) and diosmetin (2), isolated from an infusion of the plant applying chromatographic methods, were evaluated as hypoglycemic agents using the same assays. The FM-AE was tested also in rats with metabolic syndrome induced by a high-fructose fed. Finally some assays were performed to determine the antioxidant capacity of the FM-AE in vitro. RESULTS: The results demonstrated that the extracts and compounds from Anoda cristata were effective for reducing blood glucose levels in healthy and NA-STZ-hyperglycemic mice when compared with vehicle groups (p<0.05). The FM-AE exerted also positive effect over different biochemical parameters altered in rats with metabolic syndrome induced by a fructose diet. FM-AE has also antioxidant action effectively trapping ONOO(-) and ROO(â¢) radicals. The major flavonoids isolated from the plant, namely acacetin (1) and diosmetin (2), caused significant hypoglycemic effect and possessed antioxidant activity. CONCLUSION: Anoda cristata is effective to diminish glucose levels in vivo and to ameliorate different disorders related with the metabolic syndrome in rats. According to the results, the efficacy of Anoda cristata preparations could be due to the presence of active principles with different mode of actions at the molecular level, including α-glycosidases inhibitors, insulin secretagogues, glucose entrapment and radical trapping agents.