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RESUMEN Introducción La cantidad y la diversidad bacteriana intestinal están relacionadas con las enfermedades metabólicas e inflamatorias. El objetivo de este trabajo fue caracterizar la composición de la microbiota intestinal en heces y su relación con variables bioquímicas y el patrón de consumo de alimentos en individuos sanos, obesos y pacientes con diabetes mellitus tipo 2, en Mallorca (España). Métodos Las bacterias en heces se caracterizaron por PCR tiempo real. El ADN se aisló a partir de sujetos sanos (23), obesos (no diabéticos) (24) y diabéticos tipo 2 (no obesos) y se amplificó con cebadores específicos para identificar Roseburia, Clostridium leptum, Lactobacillus y Clostridium coccoides-Eubacterium rectale (Firmicutes); Prevotella y Bacteroides (Bacteroidetes); Bifidobacterium (Actinobacteria) y el cebador Universal (para total de bacterias), para la amplificación de la región V4 del gen 16S rRNA. Los resultados se analizaron estadísticamente utilizando SPSS v.21. Resultados En una población rural y urbana de Baleares, se detectaron niveles de insulina significativamente superiores en obesos (12,2 + 1,3 md/dL). En diabéticos, los niveles de triglicéridos, glucosa en sangre, hemoglobina glucosilada y albúmina en orina fueron superiores que en controles y obesos (por encima del rango normal). La mayor dispersión de las variables bioquímicas en sangre se identificó con: Clostridium coccoide-Eubacterium rectale, Bacteroides y Bifidobacterium, como posibles marcadores en obesos y diabéticos y Prevotella y Lactobacillus, como marcadores de salud. El contenido total de bacterias es mayor en controles y la relación entre reinos bacterianos es menor en este grupo. Los patrones de consumo de alimentos fueron diferentes en los tres grupos lo cual está relacionado con la variación en los patrones bacterianos. Conclusión La variabilidad en el consumo de alimentos estuvo relacionada con cinco marcadores bacterianos principales que contribuyeron a la mayor variabilidad de marcadores bioquímicos entre grupos de sujetos: Clostridium coccoide-Eubacterium rectale, Bacteroides, Bifidobacterium, Prevotella y Lactobacillus, en una población de Mallorca (España). Gut microbiota and healthy in human: obesity and type 2 diabetes mellitus.

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ABSTRACT Introduction The amount and bacterial diversity in the bowel are associated to metabolic and inflammatory diseases. The aim was to characterize the gut microbiota composition in faeces and food consumption pattern in healthy, obese and Type 2 diabetes mellitus subjects from Majorca (Spain). Methods Bacteria in faeces were characterized by Real-time PCR. DNA was isolated from healthy subjects (23), obese patients (not diabetic) (24) and type 2 diabetic patients (12) and amplified with specific primers for the identification of Roseburia, Clostridium leptum, Lactobacillus and Clostridium coccoides-Eubacterium rectale (Firmicutes); Prevotella and Bacteroides (Bacteroidetes); Bifidobacterium (Actinobacteria); and Universal primer (for all bacteria), referred to amplification of 16S rRNA gene V4 region. Results were statistically analyzed by SPSS v.21. Results A rural and urban population from Balearic Islands was tested. The insulin levels were highest in obese group (12.2 + 1.3 md/dL) while the triglyceride, blood glucose, glycosylated haemoglobin and urine albumin levels were highest in diabetic group. The major dispersion of the blood variables was identified to a bacteria core: Clostridium coccoide-Eubacterium rectale, Bacteroides and Bifidobacterium as possible markers for obese and diabetic patients; and Prevotella and Lactobacillus levels as markers of health. The total amount of bacteria is the highest in control group, such as the ratio between phyla is the lowest. The food consumptiom patterns were different among which is related to the variation in the bacterial patterns. Conclusion The variability in the foods consumption among groups was related to five bacterial markers which contributed to the major variability in blood markers: Clostridium coccoide-Eubacterium rectale, Bacteroides, Bifidobacterium, Prevotella y Lactobacillus; in a population from Majorca, Spain.

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Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Diabetes Mellitus Tipo 2/microbiología , Microbioma Gastrointestinal/fisiología , Obesidad/microbiología , Estudios de Casos y Controles , Reacción en Cadena de la Polimerasa/métodos , Heces/microbiología , Microbiología de Alimentos/clasificación

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Taking into account the sexual dimorphism previously found in white adipose tissue (WAT) regarding mitochondrial function and biogenesis, as well as insulin sensitivity, the aim of this study was to go further into the role of sex hormones in this dimorphism. To achieve this objective, we used ovariectomized rats and performed a screening by means of proteomic analyses of the periovarian WAT, combined with a study of the protein levels of specific factors involved in mitochondrial function. Rats were ovariectomized at 5 weeks of age and subcutaneously injected every 48 h with corn-oil (OVX group) or with 17ß-estradiol (E2, 10 µg/kg body mass; OVX + E2 group) for 4 weeks prior to sacrifice. Beside proteomic analysis, protein levels of Transcription Factor A, Mitochondrial (TFAM), cytochrome oxidase (COX)II, and COXIV were determined by Western blot, and mRNA levels of peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α, ERα, ERß, lipoprotein lipase (LPL), peroxisome proliferator-activated receptor-γ (PPARγ), and adiponectin were quantified by real-time PCR. Our results show that ovariectomy leads to an increase in anabolic processes and inflammatory protein levels as well as to a decrease in some of the markers of mitochondrial function, which are restored, at least in part, by E2 supplementation. Indeed, this E2 supplementation seems to be counteracted by a decline in ERα and in the ERα to ERß ratio values that could be directed to avoid an over-stimulation of the E2 signaling pathway, given the possibility of an activation of extra-gonadal steroid biosynthetic pathways.

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Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Estradiol/farmacología , Ovariectomía , Proteómica , Animales , Complejo IV de Transporte de Electrones/análisis , Complejo IV de Transporte de Electrones/metabolismo , Estradiol/administración & dosificación , Femenino , Inyecciones Subcutáneas , Ratas , Ratas Wistar , Factores de Transcripción/análisis , Factores de Transcripción/metabolismo

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Considering the sexual dimorphism described in cardiac mitochondrial function and oxidative stress, we aimed to investigate the role of 17ß-estradiol (E2) in these sex differences and the contribution of E2 receptors to these effects. As a model of chronic deprivation of ovarian hormones, we used ovariectomized (OVX) rats, half of which were treated with E2. Ovariectomy decreased markers of cardiac mitochondrial biogenesis and function and also increased oxidative stress, whereas E2 counteracted these effects. In H9c2 cardiomyocytes we observed that G-protein coupled estrogen receptor (GPER) agonist mimicked the effects of E2 in enhancing mitochondrial function and biogenesis, whereas GPER inhibitor neutralized them. These data suggest that E2 enhances mitochondrial function and decreases oxidative stress in cardiac muscle, thus it could be responsible for the sexual dimorphism observed in mitochondrial biogenesis and function in this tissue. These effects seem to be mediated through GPER stimulation.

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Estradiol/farmacología , Mitocondrias Cardíacas/metabolismo , Biogénesis de Organelos , Receptores Acoplados a Proteínas G/metabolismo , Animales , Biomarcadores/metabolismo , Peso Corporal/efectos de los fármacos , Línea Celular , Estradiol/sangre , Femenino , Mitocondrias Cardíacas/efectos de los fármacos , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Tamaño de los Órganos/efectos de los fármacos , Ovariectomía , Estrés Oxidativo/efectos de los fármacos , Progesterona/sangre , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Wistar , Receptores de Estrógenos/metabolismo

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Sexual dimorphism has been found in mitochondrial features of skeletal muscle, with female rats showing greater mitochondrial mass and function compared with males. Adiponectin is an insulin-sensitizing adipokine whose expression has been related to mitochondrial function and that is also expressed in skeletal muscle, where it exerts local metabolic effects. The aim of this research was to elucidate the role of sex hormones in modulation of mitochondrial function, as well as its relationship with adiponectin production in rat skeletal muscle. An in vivo study with ovariectomized Wistar rats receiving or not receiving 17ß-estradiol (E2) (10 µg/kg per 48 h for 4 weeks) was carried out, in parallel with an assay of cultured myotubes (L6E9) treated with E2 (10 nM), progesterone (Pg; 1 µM), or testosterone (1 µM). E2 upregulated the markers of mitochondrial biogenesis and dynamics, and also of mitochondrial function in skeletal muscle and L6E9. Although in vivo E2 supplementation only partially restored the decreased adiponectin expression levels induced by ovariectomy, these were enhanced by E2 and Pg treatment in cultured myotubes, whereas testosterone showed no effects. Adiponectin receptor 1 expression was increased by E2 treatment, both in vivo and in vitro, but testosterone decreased it. In conclusion, our results are in agreement with the sexual dimorphism previously reported in skeletal muscle mitochondrial function and indicate E2 to be its main effector, as it enhances mitochondrial function and diminishes oxidative stress. Moreover, our data support the idea of the existence of a link between mitochondrial function and adiponectin expression in skeletal muscle, which could be modulated by sex hormones.

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Adiponectina/metabolismo , Estradiol/farmacología , Mitocondrias Musculares/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adiponectina/sangre , Adiponectina/genética , Animales , Animales Recién Nacidos , Western Blotting , Células Cultivadas , Estradiol/sangre , Estrógenos/farmacología , Ácidos Grasos no Esterificados/sangre , Femenino , Masculino , Microscopía Confocal , Mitocondrias Musculares/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Fibras Musculares Esqueléticas/citología , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/citología , Músculo Esquelético/metabolismo , Ovariectomía , Oxidación-Reducción/efectos de los fármacos , Progesterona/sangre , Progesterona/farmacología , Ratas , Ratas Wistar , Receptores de Adiponectina/genética , Receptores de Adiponectina/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Testosterona/farmacología

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Sexual dimorphism has been found in both mitochondrial functionality and adiponectin expression in white adipose tissue, with female rats presenting more functional mitochondria than males and greater adiponectin expression. However, little is known about the role of sex hormones in this dimorphism. The aim was to elucidate the role of sex hormones in mitochondrial biogenesis and dynamics and in adiponectin synthesis in white adipocytes, and also to provide new evidence of the link between these processes. 3T3-L1 preadipocytes were differentiated and treated either with 17-ß estradiol (E2; 10  nM), progesterone (Pg), testosterone (1  µM both), or a combination of Pg or testosterone with flutamide (FLT; 10  µM) or E2 (1  µM). The markers of mitochondrial biogenesis and dynamics and adiponectin expression were analyzed. E2 induced mitochondrial proliferation and differentiation in 3T3-L1, although testosterone showed opposite effects. Pg treatment stimulated proliferation but impaired differentiation. In concerns mitochondrial dynamics, these hormones promoted fusion over fission. FLT treatment indicated that Pg elicits its effects on mitochondrial dynamics through the androgen receptor. E2 coadministration with testosterone or Pg reversed its effects. In conclusion, our results show that E2 induces stimulation of mitochondrial biogenesis in white adipocytes in vitro, especially in situations that imply an impairment of mitochondrial function, whereas testosterone would have opposite effects. Moreover, testosterone and Pg alter mitochondrial dynamics by promoting fusion over fission, while E2 stimulates both processes. All these alterations run in parallel with changes in adiponectin expression, thus suggesting the existence of a link between mitochondrial biogenesis and dynamics and adiponectin synthesis in white adipocytes.

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Adipocitos Blancos/metabolismo , Adiponectina/biosíntesis , Estradiol/farmacología , Recambio Mitocondrial/efectos de los fármacos , Testosterona/farmacología , Células 3T3-L1 , Adipocitos Blancos/efectos de los fármacos , Adiponectina/genética , Animales , Biomarcadores/metabolismo , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/metabolismo , Femenino , Flutamida/farmacología , Masculino , Ratones , Dinámicas Mitocondriales/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Receptores de Adiponectina/genética , Receptores de Adiponectina/metabolismo

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BACKGROUND: Mitochondrial dysfunction is thought to play a crucial role in the etiology of insulin resistance, in which skeletal muscle is the main tissue contributor. Sex differences in skeletal muscle insulin and antioxidant responses to high-fat-diet (HFD) feeding have been described. The aim of this study was to elucidate whether there is a sex dimorphism in the effects of HFD feeding on skeletal muscle mitochondrial biogenesis and on the adiponectin signaling pathway, as well as the influence of the muscle type (oxidative or glycolytic). METHODS: Gastrocnemius and soleus muscles of male and female Wistar rats of 2 months of age fed with a high-fat-diet (HFD) or a low fat diet for 26 weeks were used. Mitochondrial biogenesis and oxidative damage markers, oxidative capacity and antioxidant defences were analyzed. Serum insulin sensitivity parameters and the levels of proteins involved in adiponectin signaling pathway were also determined. RESULTS: HFD feeding induced mitochondrial biogenesis in both sexes, but to a higher degree in male rats. Although HFD female rats showed greater antioxidant protection and maintained a better insulin sensitivity profile than their male counterparts, both sexes showed an impaired response to adiponectin, which was more evident in gastrocnemius muscle. CONCLUSIONS: We conclude that HFD rats may induce skeletal muscle mitochondrial biogenesis as an attempt to compensate the deleterious consequences of adiponectin and insulin resistance on oxidative metabolism, and that the effects of HFD feeding are sex-dependent and muscle-type specific.