RESUMEN
We investigated the effects of dietary iron deficiency on the redox system in the heart. Dietary iron deficiency increased heart weight and accumulation of carbonylated proteins. However, expression levels of heme oxygenase-1 and LC3-II, an antioxidant enzyme and an autophagic marker, respectively, in iron-deficient mice were upregulated compared to the control group, resulting in a surrogate phenomenon against oxidative stress.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/biosíntesis , Proteínas del Citoesqueleto/biosíntesis , Hemo-Oxigenasa 1/biosíntesis , Hierro de la Dieta/administración & dosificación , Miocardio/metabolismo , Factor 2 Relacionado con NF-E2/biosíntesis , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Antioxidantes/metabolismo , Autofagia/efectos de los fármacos , Proteínas del Citoesqueleto/genética , Regulación de la Expresión Génica/efectos de los fármacos , Corazón/efectos de los fármacos , Hemo-Oxigenasa 1/genética , Humanos , Deficiencias de Hierro , Proteína 1 Asociada A ECH Tipo Kelch , Ratones , Factor 2 Relacionado con NF-E2/genética , Estrés Oxidativo/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Superóxido Dismutasa/metabolismoRESUMEN
Rice is the staple cereal in Senegal. Despite the many policies implemented over the last decade, Senegalese consumers still prefer imported over local rice. To understand this preference, this study compares consumer acceptability of three local rice samples versus two imported rice samples. Two focus groups and a consumer test with 120 women were carried out in the city of Saint-Louis in Senegal. The results concerning consumption habits showed that about 85% of the surveyed women consume rice at least once a day (at lunch). The hedonic test showed that consumers appreciated all five rice samples, but the most liked samples were obtained from industrial processing of either local or imported whole and fragrant rice. The least liked sample was a local semi-industrial rice, including 50% broken grains. The results of the just-about-right (JAR) test and check-all-that-apply (CATA) test showed that the sensory descriptors such as white color, well-cooked, and homogeneous grain size had an influence on the consumers' choice of rice samples. However, the most important selection criteria were the homogeneous size of the rice grains, the absence of impurities, both of which are directly linked to the milling conditions, and fragrance, which is related to the variety. The origin of the rice samples did not influence the consumers' choice. This study showed that local rice can compete with imported rice if processing is improved in some small-scale rice mills.
RESUMEN
Hamartin and tuberin interact directly to regulate cell growth negatively. In this study, far-western blotting revealed that hamartin binds directly Heat shock protein 70 (Hsp70), even in the absence of tuberin. While the hamartin-tuberin complex acts as a sensor for a variety of types of stress, it is unclear how the complex is regulated under stress conditions. We found that the hamartin-Hsp70 interaction is stabilized during heat shock. On the other hand, tuberin underwent degradation through phosphorylation in an Akt-dependent manner. Furthermore, we found that when Hsp70 expression was inhibited by N-formyl-3,4-methylenedioxy-benzylidene-gamma-butyrolactam (KNK437), Akt phosphorylation on site Ser308 diminished and tuberin was not phosphorylated at Thr1462 during heat shock. We conclude that both hamartin and Hsp70 increase in response to heat shock, whereas tuberin is phosphorylated and thereafter degraded via the PI3K/Akt pathway. Through this pathway, hamartin-Hsp70 plays a crucial role as a scaffolding protein that transfers the Akt signal to tuberin.
Asunto(s)
Proteínas HSP70 de Choque Térmico/metabolismo , Respuesta al Choque Térmico/fisiología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Animales , Western Blotting , Células COS , Chlorocebus aethiops , Proteínas HSP70 de Choque Térmico/análisis , Masculino , Ratones , Fosforilación , Ratas , Análisis Espectral , Treonina , Proteína 1 del Complejo de la Esclerosis Tuberosa , Proteína 2 del Complejo de la Esclerosis Tuberosa , Proteínas Supresoras de Tumor/químicaRESUMEN
Medicinal plants constitute an important source of potential therapeutic agents for diabetes. In the present study, we investigated the effects of Moringa oleifera (MO) Lam, Moringacea, on glucose tolerance in Wistar rats and Goto-Kakizaki (GK) rats, modeled type 2 diabetes. Major polyphenols in MO powder were quercetin glucosides, rutin, kaempferol glycosides and chlorogenic acids by HPLC analysis. As the results of glucose tolerance test, MO significantly decreased the blood glucose at 20, 30, 45and 60 min for GK rats and at 10, 30 and 45 min for Wistar rats (p<0.05) compared to the both controls after glucose administration. The area under the curve of changes in the blood glucose was significantly higher in the GK control group than in the GK plus MO group (p<0.05) in the periods 30-60 min and 60-120 min. Furthermore, MO significantly decreased stomach emptying in GK rats (p<0.05). The results indicated that MO has an ameliorating effect for glucose intolerance, and the effect might be mediated by quercetin-3-glucoside and fiber contents in MO leaf powder. The action of MO was greater in GK rats than in Wistar rats.
RESUMEN
In 2008, an epidemic of cases of renal failure among Chinese infants, due to melamine contamination of milk, raised international concern. Thus, numerous studies on the metabolism of melamine were broadly undertaken. However, little is known about placental transfer of melamine. In this study, the possibility of placental transfer of melamine and its effects on fetuses and pregnant dams were determined. Melamine was respectively administered at 0, 40 and 400mg/kg body weight by daily gavage from gestation day (GD) 13 to GD 20 to control (C), low melamine (LM) and high melamine (HM) groups of pregnant female F344 rats. Rats were sacrificed 30min after the last gavage. Melamine was not detected in any of the control and placental samples, or in amniotic fluid from the LM group. Plasma and fetal melamine concentrations in the HM group were significantly higher than in the LM group (P<0.01). Liver enzyme determination revealed no differences among the three groups. However, plasma creatinine, plasma uric acid and blood urea nitrogen concentrations in dams were significantly increased by melamine (P<0.05). These results show that ingested melamine affects renal function in dams and dose-dependently passes the placental barrier to reach the fetus.
Asunto(s)
Intercambio Materno-Fetal/fisiología , Placenta/metabolismo , Triazinas/farmacocinética , Líquido Amniótico/química , Líquido Amniótico/metabolismo , Animales , Peso Corporal/fisiología , Femenino , Feto/metabolismo , Riñón/metabolismo , Riñón/patología , Pruebas de Función Renal , Pruebas de Función Hepática , Tamaño de los Órganos/fisiología , Pinocitosis/fisiología , Embarazo , Ratas , Ratas Endogámicas F344 , Triazinas/sangreRESUMEN
Iron deficiency (ID) is one of the most commonly known forms of nutritional deficiencies. Low body iron is thought to induce neurologic defects but may also play a protective role against cancer development by cell growth arrest. Thus, ID may affect cellular pathways controlling cell growth and proliferation, the mechanism of which is still not fully understood. The serine/threonine protein kinase Akt and its downstream target, the mammalian Target of Rapamycin (mTOR), is known to play a crucial role in the regulation of cell growth and survival. Therefore, we hypothesized that Akt/mTOR pathway could be influenced by ID. Three-week-old male Wistar-strain rats were divided into 3 groups and the 2 groups had free access to a control diet (C group) or an iron-deficient diet (D group). The third group (PF group) were pair-fed the control diet to the mean intake of the D group. After 4 weeks, rats were killed and their brains were sampled. In separate experiments, COS-1 cells were cultured with or without the iron chelator deferoxamine. Western blots of brain samples and COS-1 lysates were used to analyze the expression and phosphorylation state of Akt, TSC2, mTOR, and S6 kinase proteins implicated in the Akt/mTOR pathway. Using 2 different ID models, we show for the first time that iron deficiency depresses Akt activity in rats and in COS-1 cells, leading to a decrease in mTOR activity.
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Encéfalo/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Deficiencias de Hierro , Hierro de la Dieta/farmacología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Animales , Células COS , Chlorocebus aethiops , Deferoxamina/farmacología , Regulación hacia Abajo , Masculino , Modelos Animales , Fosforilación , Ratas , Ratas Wistar , Proteínas Quinasas S6 Ribosómicas/metabolismo , Sideróforos/farmacología , Transducción de Señal , Serina-Treonina Quinasas TOR , Proteína 1 del Complejo de la Esclerosis Tuberosa , Proteína 2 del Complejo de la Esclerosis TuberosaRESUMEN
The effects of Moringa oleifera (MO), Moringaceae on hyperlipidemia and hepatocyte ultrastructural changes caused by iron deficiency were investigated. Four-week-old male Wistar-strain rats were fed a control diet based on AIN-93G (C), an iron deficient diet (FeD), a FeD + 0.5% MO (FeD-m) diet, or a FeD + MO 1% (FeD-M) diet for 4 weeks. It was found that MO reduced iron-deficient diet-induced increases in serum and hepatic lipids with dose-dependent increases of serum quercetin and kaempherol, but did not prevent anemia. By electron microscopy, in iron deficient hepatocytes, slightly swollen mitochondria and few glycogen granules were observed, but glycogen granules increased and mitochondria were normalized by treatment with MO. Furthermore, lipoproteins were observed in the Golgi complex under treatment with MO. These results suggest a possible beneficial effect of MO in the prevention of hyperlipidemia and ultrastructural changes in hepatocytes due to iron-deficiency.