RESUMEN
Adipose tissue metabolism is actively involved in the regulation of energy balance. Adipose-derived stem cells (ASCs) play a critical role in maintaining adipose tissue function through their differentiation into mature adipocytes (Ad). This study aimed to investigate the impact of an obesogenic environment on the epigenetic landscape of ASCs and its impact on adipocyte differentiation and its metabolic consequences. Our results showed that ASCs from rats on a high-fat sucrose (HFS) diet displayed reduced adipogenic capacity, increased fat accumulation, and formed larger adipocytes than the control (C) group. Mitochondrial analysis revealed heightened activity in undifferentiated ASC-HFS but decreased respiratory and glycolytic capacity in mature adipocytes. The HFS diet significantly altered the H3K4me3 profile in ASCs on genes related to adipogenesis, mitochondrial function, inflammation, and immunomodulation. After differentiation, adipocytes retained H3K4me3 alterations, confirming the upregulation of genes associated with inflammatory and immunomodulatory pathways. RNA-seq confirmed the upregulation of genes associated with inflammatory and immunomodulatory pathways in adipocytes. Overall, the HFS diet induced significant epigenetic and transcriptomic changes in ASCs, impairing differentiation and causing dysfunctional adipocyte formation.NEW & NOTEWORTHY Obesity is associated with the development of chronic diseases like metabolic syndrome and type 2 diabetes, and adipose tissue plays a crucial role. In a rat model, our study reveals how an obesogenic environment primes adipocyte precursor cells, leading to epigenetic changes that affect inflammation, adipogenesis, and mitochondrial activity after differentiation. We highlight the importance of histone modifications, especially the trimethylation of histone H3 to lysine 4 (H3K4me3), showing its influence on adipocyte expression profiles.
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Adipocitos , Adipogénesis , Tejido Adiposo , Dieta Alta en Grasa , Epigénesis Genética , Histonas , Transcriptoma , Animales , Ratas , Adipocitos/metabolismo , Dieta Alta en Grasa/efectos adversos , Histonas/metabolismo , Masculino , Adipogénesis/genética , Adipogénesis/fisiología , Tejido Adiposo/metabolismo , Diferenciación Celular/genética , Células Madre/metabolismo , Obesidad/metabolismo , Obesidad/genética , Reprogramación Celular/fisiología , Células Cultivadas , Ratas Wistar , Ratas Sprague-DawleyRESUMEN
Cardamom seed (Elettaria cardamomum (L.) Maton; EC) is consumed in several countries worldwide and is considered a nutraceutical spice since it exerts antioxidant, anti-inflammatory, and metabolic activities. In obese individuals, EC intake also favors weight loss. However, the mechanism for these effects has not been studied. Here, we identified that EC modulates the neuroendocrine axis that regulates food intake, body weight, mitochondrial activity, and energy expenditure in mice. We fed C57BL/6 mice with diets containing 3%, 6%, or 12% EC or a control diet for 14 weeks. Mice fed the EC-containing diets gained less weight than control, despite slightly higher food intake. The lower final weight of EC-fed mice was due to lesser fat content but increased lean mass than control. EC intake increased lipolysis in subcutaneous adipose tissue, and reduced adipocyte size in subcutaneous, visceral, and brown adipose tissues. EC intake also prevented lipid droplet accumulation and increased mitochondrial content in skeletal muscle and liver. Accordingly, fasting and postprandial oxygen consumption, as well as fasting fat oxidation and postprandial glucose utilization were higher in mice fed with EC than in control. EC intake reduced proopiomelanocortin (POMC) mRNA content in the hypothalamic arcuate nucleus, without an impact on neuropeptide Y (NPY) mRNA. These neuropeptides control food intake but also influence the hypothalamic-pituitary-thyroid (HPT) and hypothalamic-pituitary-adrenal (HPA) axes. Thyrotropin-releasing hormone (TRH) mRNA expression in the hypothalamic paraventricular nucleus (PVN) and circulating triiodothyronine (T3) were lower in EC-fed mice than in control. This effect was linked with decreased circulating corticosterone and weight of adrenal glands. Our results indicate that EC modulates appetite, increases lipolysis in adipose tissue and mitochondrial oxidative metabolism in liver and skeletal muscle, leading to increased energy expenditure and lower body fat mass. These metabolic effects were ascribable to the modulation of the HPT and HPA axes. LC-MS profiling of EC found 11 phenolic compounds among which protocatechuic acid (23.8%), caffeic acid (21.06%) and syringic acid (29.25%) were the most abundant, while GC-MS profiling showed 16 terpenoids among which costunolide (68.11%), ambrial (5.3%) and cis-α-terpineol (7.99%) were identified. Extrapolation of mice-to-human EC intake was performed using the body surface area normalization equation which gave a conversion equivalent daily human intake dose of 76.9-308.4 mg bioactives for an adult of 60 kg that can be obtained from 14.5-58.3 g of cardamom seeds (18.5-74.2 g cardamom pods). These results support further exploration of EC as a coadjuvant in clinical practice.
Asunto(s)
Tejido Adiposo , Elettaria , Metabolismo Energético , Lipólisis , Hígado , Músculo Esquelético , Animales , Humanos , Ratones , Tejido Adiposo Pardo , Hígado/metabolismo , Ratones Endogámicos C57BL , Músculo Esquelético/metabolismo , Estrés Oxidativo , ARN Mensajero , SemillasRESUMEN
Obesity causes systemic inflammation, hepatic and renal damage, as well as gut microbiota dysbiosis. Alternative vegetable sources rich in polyphenols are known to prevent or delay the progression of metabolic abnormalities during obesity. Vachellia farnesiana (VF) is a potent source of polyphenols with antioxidant and anti-inflammatory activities with potential anti-obesity effects. We performed an in vivo preventive or an interventional experimental study in mice and in vitro experiments with different cell types. In the preventive study, male C57BL/6 mice were fed with a Control diet, a high-fat diet, or a high-fat diet containing either 0.1% methyl gallate, 10% powdered VFP, or 0.5%, 1%, or 2% of a polyphenolic extract (PE) derived from VFP (Vachellia farnesiana pods) for 14 weeks. In the intervention study, two groups of mice were fed for 14 weeks with a high-fat diet and then one switched to a high-fat diet with 10% powdered VFP for ten additional weeks. In the in vitro studies, we evaluated the effect of a VFPE (Vachellia farnesiana polyphenolic extract) on glucose-stimulated insulin secretion in INS-1E cells or of naringenin or methyl gallate on mitochondrial activity in primary hepatocytes and C2C12 myotubes. VFP or a VFPE increased whole-body energy expenditure and mitochondrial activity in skeletal muscle; prevented insulin resistance, hepatic steatosis, and kidney damage; exerted immunomodulatory effects; and reshaped fecal gut microbiota composition in mice fed a high-fat diet. VFPE decreased insulin secretion in INS-1E cells, and its isolated compounds naringenin and methyl gallate increased mitochondrial activity in primary hepatocytes and C2C12 myotubes. In conclusion VFP or a VFPE prevented systemic inflammation, insulin resistance, and hepatic and renal damage in mice fed a high-fat diet associated with increased energy expenditure, improved mitochondrial function, and reduction in insulin secretion.
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Dieta Alta en Grasa , Resistencia a la Insulina , Masculino , Animales , Ratones , Dieta Alta en Grasa/efectos adversos , Prebióticos , Ratones Endogámicos C57BL , Obesidad/metabolismo , Extractos Vegetales/farmacología , Inflamación/tratamiento farmacológicoRESUMEN
BACKGROUND: Plasminogen activator inhibitor 1 (PAI-1) and resistin are associated with dysfunctional adipose tissue (AT)-related metabolic complications. The role of dietary eicosapentaenoic (EPA) and docosahexaenoic (DHA) fatty acids in this relationship is unknown. AIM: To investigate the association of EPA and DHA with PAI-1 and resistin, as well as the role of this association on the glucose metabolism of apparently healthy subjects. SUBJECTS AND METHODS: Thirty-six healthy individuals were included. Validated food frequency questionnaires were used to analyse dietary habits. Inflammatory and glucose metabolism markers were quantified. Subcutaneous AT samples were obtained, and adipocyte number, area, and macrophage content were assessed. RESULTS: In 36 subjects aged 56 ± 8 years and with a body mass index of 26 ± 4 kg/m2, logEPA, and logDHA showed significant association with logresistin and a marginal association with PAI-1. Adipocyte number, area, and lognumber of macrophages per adipocyte significantly correlated with PAI-1 but not with logresistin. Although logEPA and logDHA were independently associated with loginsulin, loginsulin resistance, and C-Peptide, the addition of logresistin, but not of PAI-1, into the multivariable model, abolished the associations. CONCLUSIONS: EPA and DHA could modulate glucose metabolism across AT functional states. Our data indicate that this association is independent of other metabolic risk factors.
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Ácidos Grasos Omega-3 , Inhibidor 1 de Activador Plasminogénico , Humanos , Inhibidor 1 de Activador Plasminogénico/metabolismo , Resistina/metabolismo , Ácido Eicosapentaenoico/metabolismo , Ácido Eicosapentaenoico/farmacología , Autoinforme , Voluntarios Sanos , Ácidos Docosahexaenoicos/metabolismo , Ácidos Docosahexaenoicos/farmacología , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-3/farmacología , Tejido Adiposo/metabolismo , Glucosa/metabolismoRESUMEN
BACKGROUND: Dietary bioactive compounds have been demonstrated to produce several health benefits. Genistein, an isoflavone of soy protein, and resveratrol, a polyphenol from grapes, have been shown to improve insulin sensitivity and to stimulate white adipose tissue (WAT) browning, leading to increased energy expenditure. However, it has not been demonstrated in humans whether genistein or resveratrol have the capacity to stimulate the differentiation of stromal vascular fraction (SVF) cells from white fat into beige adipocytes. SUBJECTS/METHODS: With this aim, we assessed whether stromal vascular fraction cells obtained from biopsies of the subdermal fat depots of subjects with normal body weight (NW) or from subjects with overweight/obesity with (OIR) or without (OIS) insulin resistance were able to differentiate into the beige adipose tissue lineage in vitro, by exposing the cells to genistein, resveratrol, or the combination of both. RESULTS: The results showed that SVF cells obtained from NW or OIS subjects were able to differentiate into beige adipocytes according to an increased expression of beige biomarkers including UCP1, PDRM-16, PGC1α, CIDEA, and SHOX2 upon exposure to genistein. However, SVF cells from OIR subjects were unable to differentiate into beige adipocytes with any of the inducers. Exposure to resveratrol or the combination of resveratrol/genistein did not significantly stimulate the expression of browning markers in any of the groups studied. We found that the non-responsiveness of the SVF from subjects with obesity and insulin resistance to any of the inducers was associated with an increase in the expression of endoplasmic reticulum stress markers. CONCLUSION: Consumption of genistein may stimulate WAT browning mainly in NW or OIS subjects. Thus, obesity associated with insulin resistance may be considered as a condition that prevents some beneficial effects of some dietary bioactive compounds.
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Adipocitos Beige/fisiología , Diferenciación Celular/efectos de los fármacos , Genisteína/farmacología , Resistencia a la Insulina/fisiología , Fracción Vascular Estromal/fisiología , Adulto , Diferenciación Celular/fisiología , Femenino , Humanos , Masculino , Psicometría/instrumentación , Psicometría/métodos , Fracción Vascular Estromal/metabolismo , Encuestas y CuestionariosRESUMEN
Tuberculosis (TB) is the leading cause of death from a single bacterial infectious agent and is one of the most relevant issues of public health. Another pandemic disease is type II diabetes mellitus (T2D) that is estimated to affect half a billion people in the world. T2D is directly associated with obesity and a sedentary lifestyle and is frequently associated with immunosuppression. Immune dysfunction induced by hyperglycemia increases infection frequency and severity. Thus, in developing countries the T2D/TB co-morbidity is frequent and represents one of the most significant challenges for the health-care systems. Several immunoendocrine abnormalities are occurring during the chronic phase of both diseases, such as high extra-adrenal production of active glucocorticoids (GCs) by the activity of 11-ß-hydroxysteroid dehydrogenase type 1 (11-ßHSD1). 11-ßHSD1 catalyzes the conversion of inactive cortisone to active cortisol or corticosterone in lungs and liver, while 11-ß-hydroxysteroid dehydrogenase type 2 (11-ßHSD2) has the opposite effect. Active GCs have been related to insulin resistance and suppression of Th1 responses, which are deleterious factors in both T2D and TB. The anabolic adrenal hormone dehydroepiandrosterone (DHEA) exerts antagonistic effects on GC signaling in immune cells and metabolic tissues; however, its anabolic effects prohibit its use to treat immunoendocrine diseases. 16α-bromoepiandrosterone (BEA) is a water miscible synthetic sterol related to DHEA that lacks an anabolic effect while amplifying the immune and metabolic properties with important potential therapeutic uses. In this work, we compared the expression of 11-ßHSD1 and the therapeutic efficacy of BEA in diabetic mice infected with tuberculosis (TB) (T2D/TB) with respect to non-diabetic TB-infected mice (TB). T2D was induced by feeding mice with a high-fat diet and administering a single low-dose of streptozotocin. After 4 weeks of T2D establishment, mice were infected intratracheally with a high-dose of Mycobacterium tuberculosis strain H37Rv. Then, mice were treated with BEA three times a week by subcutaneous and intratracheal routes. Infection with TB increased the expression of 11-ßHSD1 and corticosterone in the lungs and liver of both T2D/TB and TB mice; however, T2D/TB mice developed a more severe lung disease than TB mice. In comparison with untreated animals, BEA decreased GC and 11-ßHSD1 expression while increasing 11-ßHSD2 expression. These molecular effects of BEA were associated with a reduction in hyperglycemia and liver steatosis, lower lung bacillary loads and pneumonia. These results uphold BEA as a promising effective therapy for the T2D/TB co-morbidity.
Asunto(s)
Androsterona/farmacología , Antituberculosos/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/farmacología , Tuberculosis/tratamiento farmacológico , 11-beta-Hidroxiesteroide Deshidrogenasas/metabolismo , Animales , Comorbilidad , Corticosterona/farmacología , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animales de Enfermedad , Hidrocortisona/metabolismo , Pulmón/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis/metabolismoRESUMEN
OBJECTIVE: To use the combined presence of the elevated insulin resistance index in adipose tissue (Adipo-IR) and low values of adiponectin as a marker of dysfunctional adipose tissue, and to analyze its possible association with low values of high-density lipoprotein cholesterol (HDL-C) and small size of HDL particles. RESEARCH DESIGN AND METHODS: The analysis included 253 subjects with functional adipose tissue and 253 with dysfunctional adipose tissue, considering similar gender, age, and body mass index (BMI). Adipo-IR was considered when index values (free fatty acids × insulin concentrations) were ≥75th percentile. Low levels of adiponectin were considered when concentration in serum was <25th percentile (determined by ELISA). HDL size was estimated by a quantitative validated equation. Small HDL size was considered when values were <25th percentile. RESULTS: When comparing subjects with functional adipose tissue with those of dysfunctional adipose tissue, the latter had a higher prevalence of low HDL-C (51.4% vs. 64.0%; p = 0.004) and small HDL (56.9% vs. 67.6%; p = 0.009). Multivariate analysis indicated that independently from other metabolic risk factors, dysfunction of adipose tissue is significantly associated with low HDL-C (OR: 1.624 [CI 95%: 1.100-2.397]) and small HDL (OR: 1.462 [CI 95%: 1.000-2.139]). Adding BMI, waist circumference, and subcutaneous or visceral adipose tissue did not modify the association. CONCLUSIONS: Dysfunction of adipose tissue is associated with a 65 and 50% higher probability of having low HDL-C and small HDL. Identification of dysfunctional adipose tissue could be a useful tool in the clinical setting to prevent the cardiometabolic risk independently from adiposity.
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Tejido Adiposo Blanco , HDL-Colesterol , Tejido Adiposo Blanco/citología , Tejido Adiposo Blanco/diagnóstico por imagen , Tejido Adiposo Blanco/fisiopatología , Índice de Masa Corporal , Peso Corporal/fisiología , HDL-Colesterol/sangre , HDL-Colesterol/química , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad , Tamaño de la Partícula , Circunferencia de la Cintura/fisiologíaRESUMEN
Goat's milk is a rich source of bioactive compounds (peptides, conjugated linoleic acid, short chain fatty acids, monounsaturated and polyunsaturated fatty acids, polyphenols such as phytoestrogens and minerals among others) that exert important health benefits. However, goat's milk composition depends on the type of food provided to the animal and thus, the abundance of bioactive compounds in milk depends on the dietary sources of the goat feed. The metabolic impact of goat milk rich in bioactive compounds during metabolic challenges such as a high-fat (HF) diet has not been explored. Thus, we evaluated the effect of milk from goats fed a conventional diet, a conventional diet supplemented with 30% Acacia farnesiana (AF) pods or grazing on metabolic alterations in mice fed a HF diet. Interestingly, the incorporation of goat's milk in the diet decreased body weight and body fat mass, improved glucose tolerance, prevented adipose tissue hypertrophy and hepatic steatosis in mice fed a HF diet. These effects were associated with an increase in energy expenditure, augmented oxidative fibers in skeletal muscle, and reduced inflammatory markers. Consequently, goat's milk can be considered a non-pharmacologic strategy to improve the metabolic alterations induced by a HF diet. Using the body surface area normalization method gave a conversion equivalent daily human intake dose of 1.4 to 2.8 glasses (250 mL per glass/day) of fresh goat milk for an adult of 60 kg, which can be used as reference for future clinical studies.
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Metabolismo Energético/efectos de los fármacos , Ácidos Grasos/administración & dosificación , Hígado Graso/prevención & control , Leche/química , Mitocondrias Musculares/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Obesidad/prevención & control , Animales , Biomarcadores/análisis , Dieta Alta en Grasa/efectos adversos , Suplementos Dietéticos , Hígado Graso/etiología , Expresión Génica/efectos de los fármacos , Cabras , Resistencia a la Insulina , Ácidos Linoleicos Conjugados/administración & dosificación , Masculino , Ratones Endogámicos C57BL , Mitocondrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Obesidad/etiologíaRESUMEN
Obesity is associated with an increase of several metabolic disorders leading to the development of diseases such as type 2 diabetes and cardiovascular disease. This is due in part to the ectopic accumulation of triglycerides in organs that are non-adipose tissues, leading to lipotoxicity. Particularly, in the liver, the accumulation of lipids, mainly of triglycerides, leads to the formation of fatty liver. The accumulation of lipids in skeletal muscle and pancreas associates with insulin resistance and a decrease in insulin secretion, respectively. In addition, it has been suggested that dysbiosis of the gut microbiota can contribute to the process of lipid accumulation in non-adipose tissues, especially in the liver. The aim of the present review is to highlight the mechanisms associated with the development of lipotoxicity, and how with the advances in nutrigenomics, it is now possible to understand the molecular mechanisms by which some nutrients can attenuate the ectopic accumulation of triglycerides in non-adipose tissues. Particularly, we emphasize research conducted on the molecular mechanisms of action of soy protein and some of its isoflavones, and how these can reduce lipotoxicity by preventing the accumulation of lipids in the liver, skeletal muscle, and pancreas, as well as their role on the gut microbiota to attenuate the development of fatty liver. Thus, nutrigenomics is opening new dietary strategies based on several functional foods that can be used to ameliorate the pathologies associated with lipotoxicity.
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Nutrigenómica , Obesidad/complicaciones , Proteínas de Soja/farmacología , Animales , Humanos , Metabolismo de los Lípidos , Trastornos del Metabolismo de los Lípidos/prevención & controlRESUMEN
Subcutaneous (SAT) and visceral (VAT) adipose tissues stores excess energy as triglycerides and synthesize adiponectin to prevent ectopic lipid accumulation and lipotoxicity. During obesity, an impairment in the capacity of SAT to store triglycerides and synthesize adiponectin is associated with increased free fatty acids (FFA) release, leading to VAT hypertrophy and hepatic and skeletal muscle lipotoxicity. Endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) may be involved in SAT dysfunction during obesity. The objectives of this study were to assess UPR activation and adiponectin synthesis in: 1) SAT and VAT from mice exposed to acute pharmacologic or chronic obesity-induced ER stress and in 2) cultured mice primary mature adipocytes or adipocytes differentiated in vitro from SAT and VAT exposed to tunicamycin or thapsigargin. Mice fed a high-fat diet developed obesity, increased FFA and lower circulating adiponectin in association with lower adiponectin synthesis and increased UPR markers in SAT. Mice subjected to acute ER stress by pioglitazone administration and a low-dose tunicamycin injection presented a maladaptive UPR activation in SAT along with reduced adiponectin synthesis and secretion and increased lipolysis with respect to VAT, associated with lipid accumulation in skeletal muscle and liver. Primary adipocytes and adipocytes differentiated from SAT exposed to pharmacologic ER stress also developed maladaptive UPR, along with reduced adiponectin synthesis and increased lipolysis with respect to those from VAT. Our results indicate that compared to VAT, SAT is more susceptible to ER stress, leading to increased lipolysis and reduced adiponectin synthesis and secretion.
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Adipocitos/patología , Adiponectina/metabolismo , Estrés del Retículo Endoplásmico , Obesidad/fisiopatología , Grasa Subcutánea/patología , Adipocitos/metabolismo , Animales , Femenino , Lipólisis , Masculino , Ratones , Ratones Endogámicos C57BL , Grasa Subcutánea/metabolismoRESUMEN
The STE20/SPS1-related proline-alanine-rich protein kinase (SPAK) controls the activity of the electroneutral cation-chloride cotransporters (SLC12 family) and thus physiological processes such as modulation of cell volume, intracellular chloride concentration [Cl-]i, and transepithelial salt transport. Modulation of SPAK kinase activity may have an impact on hypertension and obesity, as STK39, the gene encoding SPAK, has been suggested as a hypertension and obesity susceptibility gene. In fact, the absence of SPAK activity in mice in which the activating threonine in the T loop was substituted by alanine (SPAK-KI mice) is associated with decreased blood pressure; however its consequences in metabolism have not been explored. Here, we fed wild-type and homozygous SPAK-KI mice a high-fat diet for 17 wk to evaluate weight gain, circulating substrates and hormones, energy expenditure, glucose tolerance, and insulin sensitivity. SPAK-KI mice exhibit resistance to HFD-induced obesity and hepatic steatosis associated with increased energy expenditure, higher thermogenic activity in brown adipose tissue, increased mitochondrial activity in skeletal muscle, and reduced white adipose tissue hypertrophy mediated by augmented whole body insulin sensitivity and glucose tolerance. Our data reveal a previously unrecognized role for the SPAK kinase in the regulation of energy balance, thermogenesis, and insulin sensitivity, suggesting that this kinase could be a new drug target for the treatment of obesity and the metabolic syndrome.
Asunto(s)
Dieta Alta en Grasa/efectos adversos , Metabolismo Energético/genética , Resistencia a la Insulina/genética , Proteínas Serina-Treonina Quinasas/genética , Aumento de Peso/genética , Animales , Células Cultivadas , Grasas de la Dieta/farmacología , Metabolismo Energético/efectos de los fármacos , Técnicas de Sustitución del Gen , Silenciador del Gen , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas Serina-Treonina Quinasas/fisiología , Aumento de Peso/efectos de los fármacosRESUMEN
Branched-chain amino acid (BCAA) catabolism is regulated by the branched-chain aminotransferase (BCAT2) and the branched-chain α-keto acid dehydrogenase complex (BCKDH). BCAT2 and BCKDH expression and activity are modified during adipogenesis and altered in adipose tissues of mice with genetic or diet-induced obesity. However, little is known about how these modifications and alterations affect the intracellular metabolic fate of BCAAs during adipogenesis, in adipocytes from mice fed a control or high-fat diet or in C2C12 myotubes. Here, we demonstrate that BCAAs are mainly incorporated into proteins during the early stages of adipocyte differentiation. However, they are oxidized and incorporated into lipids during the late days of differentiation. Conversely, 92% and 97% of BCAA were oxidized, 1.6% and 6% were used for protein synthesis and 1.2% and 1.5% were incorporated into lipids in adipocytes from epididymal and subcutaneous adipose tissue, respectively. All three pathways were decreased in adipocytes from mice fed a high-fat diet. In C2C12 myotubes, leucine is mainly used for protein synthesis and palmitate is incorporated into lipids. Interestingly, leucine decreased both palmitate oxidation and its incorporation to lipids and proteins; and palmitate increased leucine oxidation and decreased its incorporation to lipids and proteins in a dose-dependent manner. These results demonstrate that BCAA metabolic fate differs between the early and late stages of adipocyte differentiation and in adipocytes from mice fed a control or high-fat diet; and that leucine affects the metabolic fate of palmitate and vice versa in C2C12 myotubes. J. Cell. Biochem. 118: 808-818, 2017. © 2016 Wiley Periodicals, Inc.
Asunto(s)
Adipocitos/metabolismo , Adipogénesis/fisiología , Aminoácidos de Cadena Ramificada/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Obesidad/metabolismo , 3-Metil-2-Oxobutanoato Deshidrogenasa (Lipoamida)/genética , 3-Metil-2-Oxobutanoato Deshidrogenasa (Lipoamida)/metabolismo , Células 3T3-L1 , Adipocitos/patología , Adipogénesis/genética , Animales , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Línea Celular , Células Cultivadas , Dieta Alta en Grasa/efectos adversos , Metabolismo de los Lípidos , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/genética , Ácido Palmítico/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transaminasas/genética , Transaminasas/metabolismoRESUMEN
BACKGROUND: The study of NAFLD in humans has several limitations. Using murine models helps to understand disease pathogenesis. AIM: Evaluate the impact of 4 different diets in the production of NAFLD with emphasis on a combined high-fat plus sustained high sucrose consumption. MATERIAL AND METHODS: Eight week-old male Wistar rats were divided in four groups and fed for 90 days with the following diets: 1) Control chow diet (C); 2) High-fat cholesterol diet (HFC) + 5% sucrose in drinking water. 3) High-fat cornstarch diet (HFCO) + 5% sucrose in drinking water. 4) Chow diet + 20% sucrose in drinking water (HSD). Metabolic changes, leptin levels, liver histology, hepatic and plasma lipid composition, fasting plasma glucose and insulin and liver gene expression of FAS, SREBP-1 and PPAR-α were evaluated. RESULTS: The HFC diet had the highest grade of steatosis (grade 2 of 3) and HSD showed also steatosis (grade 1). Liver weight TG and colesterol concentrations in liver were greater in the HFC diet. There were no increased levels of iron in the liver. Rats in HFC gained significantly more weight (P < 0.001). All experimental groups showed fasting hyperglycemia. HFC had the highest glucose level (158.5 ± 7 mg/dL) (P < 0.005). The HSD and the HFCO diets developed also hyperglycemia. HSD had significantly higher fasting hyperinsulinemia. Serum leptin was higher in the HFC diet (p = 0.001). In conclusion, the HFC diet with combination of high fat and high sucrose is more effective in producing NAFLD compared with a high sucrose diet only.
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Dieta Alta en Grasa , Sacarosa en la Dieta , Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/etiología , Animales , Biomarcadores/sangre , Glucemia/metabolismo , Sacarosa en la Dieta/sangre , Modelos Animales de Enfermedad , Ácido Graso Sintasas/genética , Ácido Graso Sintasas/metabolismo , Regulación de la Expresión Génica , Hiperglucemia/sangre , Hiperglucemia/etiología , Hiperglucemia/genética , Hiperinsulinismo/sangre , Hiperinsulinismo/etiología , Hiperinsulinismo/genética , Insulina/sangre , Hierro/metabolismo , Leptina/sangre , Lípidos/sangre , Hígado/patología , Masculino , Enfermedad del Hígado Graso no Alcohólico/sangre , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , PPAR alfa/genética , PPAR alfa/metabolismo , Ratas Wistar , Índice de Severidad de la Enfermedad , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Factores de Tiempo , Aumento de PesoRESUMEN
Black bean (Phaseolus vulgaris L.) seed coats are a rich source of natural compounds with potential beneficial effects on human health. Beans exert hypolipidaemic activity; however, this effect has not been attributed to any particular component, and the underlying mechanisms of action and protein targets remain unknown. The aim of the present study was to identify and quantify primary saponins and flavonoids extracted from black bean seed coats, and to study their effects on lipid metabolism in primary rat hepatocytes and C57BL/6 mice. The methanol extract of black bean seed coats, characterised by a HPLC system with a UV-visible detector and an evaporative light-scattering detector and HPLC-time-of-flight/MS, contained quercetin 3-O-glucoside and soyasaponin Af as the primary flavonoid and saponin, respectively. The extract significantly reduced the expression of SREBP1c, FAS and HMGCR, and stimulated the expression of the reverse cholesterol transporters ABCG5/ABCG8 and CYP7A1 in the liver. In addition, there was an increase in the expression of hepatic PPAR-α. Consequently, there was a decrease in hepatic lipid depots and a significant increase in bile acid secretion. Furthermore, the ingestion of this extract modulated the proportion of lipids that was used as a substrate for energy generation. Thus, the results suggest that the extract of black bean seed coats may decrease hepatic lipogenesis and stimulate cholesterol excretion, in part, via bile acid synthesis.
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Colagogos y Coleréticos/uso terapéutico , Suplementos Dietéticos , Flavonoides/uso terapéutico , Lipotrópicos/uso terapéutico , Phaseolus/química , Saponinas/uso terapéutico , Semillas/química , Animales , Ácidos y Sales Biliares/metabolismo , Células Cultivadas , Colagogos y Coleréticos/química , Colagogos y Coleréticos/aislamiento & purificación , Colagogos y Coleréticos/metabolismo , Colesterol/metabolismo , Flavonoides/química , Flavonoides/aislamiento & purificación , Flavonoides/metabolismo , Regulación de la Expresión Génica , Hepatocitos/citología , Hepatocitos/enzimología , Hepatocitos/metabolismo , Metabolismo de los Lípidos , Lipotrópicos/química , Lipotrópicos/aislamiento & purificación , Lipotrópicos/metabolismo , Receptores X del Hígado , Masculino , México , Ratones , Ratones Endogámicos C57BL , Receptores Nucleares Huérfanos/agonistas , Receptores Nucleares Huérfanos/genética , Receptores Nucleares Huérfanos/metabolismo , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/metabolismo , Extractos Vegetales/uso terapéutico , Distribución Aleatoria , Ratas , Saponinas/química , Saponinas/aislamiento & purificación , Saponinas/metabolismoRESUMEN
Several endocrine disrupting compounds released from plastics, including polyfluoroalkyl substances, bisphenols, flame retardants, phthalates and others, are of great concern to human health due to their high toxicity. This review discusses the effects of di-(2-ethylhexyl) phthalate (DEHP), the most common member of the phthalate family, on female reproduction. In vitro and in vivo studies link DEHP exposure to impaired hypothalamic-pituitary-ovarian s (HPO) axis function, alteration of steroid-hormone levels and dysregulation of their receptors, and changes in uterine morphophysiology. In addition, high urinary DEPH levels have been associated with several reproductive disorders in women, including endometriosis, fibromyoma, fetal growth restriction and pregnancy loss. These data suggest that DEHP may be involved in the pathophysiology of various female reproductive diseases. Therefore, exposure to these compounds should be considered a concern in clinician surveillance practices for women at reproductive age and should be regulated to protect their health and that of their progeny.
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Dietilhexil Ftalato , Disruptores Endocrinos , Ácidos Ftálicos , Embarazo , Femenino , Humanos , Dietilhexil Ftalato/toxicidad , Salud Reproductiva , Reproducción , Ácidos Ftálicos/toxicidad , Disruptores Endocrinos/toxicidadRESUMEN
Autism spectrum disorder (ASD) is a psychiatric condition characterized by reduced social interaction, anxiety, and stereotypic behaviors related to neuroinflammation and microglia activation. We demonstrated that maternal exposure to Western diet (cafeteria diet or CAF) induced microglia activation, systemic proinflammatory profile, and ASD-like behavior in the offspring. Here, we aimed to identify the effect of alternate day fasting (ADF) as a non-pharmacologic strategy to modulate neuroinflammation and ASD-like behavior in the offspring prenatally exposed to CAF diet. We found that ADF increased plasma beta-hydroxybutyrate (BHB) levels in the offspring exposed to control and CAF diets but not in the cortex (Cx) and hippocampus (Hpp). We observed that ADF increased the CD45 + cells in Cx of both groups; In control individuals, ADF promoted accumulation of CD206 + microglia cells in choroid plexus (CP) and increased in CD45 + macrophages cells and lymphocytes in the Cx. Gestational exposure to CAF diet promoted defective sociability in the offspring; ADF improved social interaction and increased microglia CD206 + in the Hpp and microglia complexity in the dentate gyrus. Additionally, ADF led to attenuation of the ER stress markers (Bip/ATF6/p-JNK) in the Cx and Hpp. Finally, biological modeling showed that fasting promotes higher microglia complexity in Cx, which is related to improvement in social interaction, whereas in dentate gyrus sociability is correlated with less microglia complexity. These data suggest a contribution of intermittent fasting as a physiological stimulus capable of modulating microglia phenotype and complexity in the brain, and social interaction in male mice.
RESUMEN
Insulin resistance (IR) refers to a reduction in the ability of insulin to exert its metabolic effects in organs such as adipose tissue (AT) and skeletal muscle (SM), leading to chronic diseases such as type 2 diabetes, hepatic steatosis, and cardiovascular diseases. Obesity is the main cause of IR, however not all subjects with obesity develop clinical insulin resistance, and not all clinically insulin-resistant people have obesity. Recent evidence implies that IR onset is tissue-dependent (AT or SM) and/or substrate-specific (glucometabolic or lipometabolic). Therefore, the aims of the present review are 1) to describe the glucometabolic and lipometabolic activities of insulin in AT and SM in the maintenance of whole-body metabolic homeostasis, 2) to discuss the pathophysiology of substrate-specific IR in AT and SM, and 3) to highlight novel validated tests to assess tissue and substrate-specific IR that are easy to perform in clinical practice. In AT, glucometabolic IR reduces glucose availability for glycerol and fatty acid synthesis, thus decreasing the esterification and synthesis of signaling bioactive lipids. Lipometabolic IR in AT impairs the antilipolytic effect of insulin and lipogenesis, leading to an increase in circulating FFAs and generating lipotoxicity in peripheral tissues. In SM, glucometabolic IR reduces glucose uptake, whereas lipometabolic IR impairs mitochondrial lipid oxidation, increasing oxidative stress and inflammation, all of which lead to metabolic inflexibility. Understanding tissue-dependent and substrate-specific IR is of paramount importance for early detection before clinical manifestations and for the development of more specific treatments or direct interventions to prevent chronic life-threatening diseases.
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Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Tejido Adiposo/metabolismo , Insulina/metabolismo , Obesidad/metabolismo , Tejido Adiposo Blanco/metabolismo , Músculo Esquelético/metabolismoRESUMEN
Dietary regimens that are focused on diminishing total caloric intake and restricting palatable food ingestion are the most common strategies for weight control. However, restrictive diet therapies have low adherence rates in obese patients, particularly in stressed individuals. Moreover, food restriction downregulates the hypothalamic-pituitary-thyroid axis (HPT) function, hindering weight loss. Intermittent fasting (IF) has emerged as an option to treat obesity. We compared the effects of IF to an all-day feeding schedule on palatable diet (PD)-stress (S)-induced hyperphagia, HPT axis function, accumbal thyrotropin-releasing hormone (TRH), and dopamine D2 receptor expression in association with adipocyte size and PPARÆ coactivator 1α (PGC1α) and uncoupling protein 1 (UCP1) expression in stressed vs. non-stressed rats. After 5 weeks, S-PD rats showed an increased energy intake and adipocyte size, fewer beige cells, and HPT axis deceleration-associated low PGC1α and UCP1 expression, as well as decreased accumbal TRH and D2 expression. Interestingly, IF reversed those parameters to control values and increased the number of beige adipocytes, UCP1, and PGC1α mRNAs, which may favor a greater energy expenditure and a reduced body weight, even in stressed rats. Our results showed that IF modulated the limbic dopaminergic and TRHergic systems that regulate feeding and HPT axis function, which controls the metabolic rate, supporting this regimen as a suitable non-pharmacologic strategy to treat obesity, even in stressed individuals.
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Sistema Hipotálamo-Hipofisario , Glándula Tiroides , Ratas , Animales , Glándula Tiroides/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Sistema Hipotálamo-Hipofisario/metabolismo , Ayuno Intermitente , Hormona Liberadora de Tirotropina , Peso Corporal , Obesidad/metabolismo , Ingestión de AlimentosRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Chaya (Cnidoscolus aconitifolius (Mill.) I.M. Johnst) is an important component of the regular diet and traditional medicine of indigenous communities in Mexico. Customarily, Chaya is consumed as a beverage made of macerated leaf, cooked, or prepared in teas or infusions to empirically treat obesity, diabetes, gastrointestinal disorders, and kidney stones. The beneficial effects of Chaya can be attributed to the presence of protein, dietary fiber, vitamins, and especially polyphenols, which regulate mitochondrial function. Therefore, polyphenols present in Chaya extracts could be used to develop novel strategies to prevent and treat metabolic alterations related to mitochondrial dysfunction in the muscle and liver of subjects with obesity, type 2 diabetes, and cardiovascular diseases. However, limited information is available concerning the effect of Chaya extracts on mitochondrial activity in those tissues. AIM OF THE STUDY: The aim of this study was to evaluate the antioxidant capacity of an aqueous extract (AE) or mixed (methanol/acetone/water) extract (ME) of Chaya leaf and their effect on C2C12 myotubes and primary hepatocyte mitochondrial bioenergetics and fatty acid oxidation (FAO). MATERIALS AND METHODS: Total polyphenol content and antioxidant activity were determined using the Folin-Ciocalteu method and the oxygen radical absorbance capacity assay, respectively. The effect of AE and ME from Chaya leaf on mitochondrial activity and FAO of C2C12 myotubes and primary hepatocytes was evaluated using an extracellular flux analyzer. RESULTS: The AE and ME from Chaya leaf exhibited antioxidant activity and a polyphenol content similar to nopal, another plant used in Mexican traditional medicine. AE significantly (p < 0.05) decreased the maximal respiration and spare respiratory capacity (SRC) of C2C12 cells, whereas ME had little effect on C2C12 mitochondrial function. Conversely, ME significantly (p < 0.05) decreased SRC in primary hepatocytes, whereas AE increased maximal respiration and SRC at low doses (5 and 10 µM). Moreover, low doses of Chaya AE significantly (p < 0.05) increased AMPK phosphorylation, acyl-coenzyme A oxidase protein abundance, and palmitate oxidation in primary hepatocytes. CONCLUSION: The AE of Chaya leaf increases mitochondrial function and FAO of primary hepatocytes, indicating its potential to treat hepatic mitochondrial dysfunction underlying metabolic diseases.