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1.
J Med Food ; 21(10): 1044-1052, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29792544

RESUMO

Menopause induces a loss of bone as a result of estrogen deficiency. Despite pharmaceutical options for the treatment of osteopenia and osteoporosis, many aging women use dietary supplements with estrogenic activity to prevent bone loss and other menopausal-related symptoms. Such supplements are yet to be tested for efficacy against a Food and Drug Administration (FDA) approved medication for menopausal bone loss such as zoledronic acid (ZA). The postmenopausal rat model was used to investigate the efficacy of various synergistic phytochemical blends mixed into the diet for 16 weeks. Retired-breeder, Fischer 344 rats were randomly assigned to sham or ovariectomy surgery and 4 treatment groups: ZA; genistein supplementation; and a low dose and high dose blend of genistein, resveratrol, and quercetin. Ovariectomy resulted in a loss of both trabecular and cortical bone which was prevented with ZA. The phytochemical blends tested were unable to reverse these losses. Despite the lack of effectiveness in preventing bone loss, a significant dose-response trend was observed in the phytochemical-rich diets in bone adipocyte number compared to ovariectomized control rats. Data from this study indicate that estrogenic phytochemicals are not as efficacious as ZA in preventing menopausal-related bone loss but may have beneficial effects on bone marrow adiposity in rats.


Assuntos
Osteoporose Pós-Menopausa/tratamento farmacológico , Compostos Fitoquímicos/administração & dosagem , Adiposidade/efeitos dos fármacos , Animais , Densidade Óssea/efeitos dos fármacos , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Genisteína/administração & dosagem , Humanos , Osteoporose Pós-Menopausa/etiologia , Osteoporose Pós-Menopausa/fisiopatologia , Ovariectomia/efeitos adversos , Quercetina/administração & dosagem , Ratos , Ratos Endogâmicos F344 , Resveratrol/administração & dosagem
2.
BMC Obes ; 3: 35, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27462403

RESUMO

BACKGROUND: Obesity-related comorbidities are thought to result from the reprogramming of the epigenome in numerous tissues and cell types, and in particular, mature adipocytes within visceral and subcutaneous adipose tissue, VAT and SAT. The cell-type specific chromatin remodeling of mature adipocytes within VAT and SAT is poorly understood, in part, because of the difficulties of isolating and manipulating large fragile mature adipocyte cells from adipose tissues. METHODS: We constructed MA-INTACT (Mature Adipocyte-Isolation of Nuclei TAgged in specific Cell Types) mice using the adiponectin (ADIPOQ) promoter (ADNp) to tag the surface of mature adipocyte nuclei with a reporter protein. The SUN1mRFP1Flag reporter is comprised of a fragment of the nuclear transmembrane protein SUN1, the fluorescent protein mRFP1, and three copies of the Flag epitope tag. RESULTS: Mature adipocyte nuclei were rapidly and efficiently immuno-captured from VAT and SAT (MVA and MSA nuclei, respectively), of MA-INTACT mice. MVA and MSA nuclei contained 1,000 to 10,000-fold higher levels of adipocyte-specific transcripts, ADIPOQ, PPARg2, EDNRB, and LEP, relative to uncaptured nuclei, while the latter expressed higher levels of leukocyte and endothelial cell markers IKZF1, RETN, SERPINF1, SERPINE1, ILF3, and TNFA. MVA and MSA nuclei differentially expressed several factors linked to adipogenesis or obesity-related health risks including CEBPA, KLF2, RETN, SERPINE1, and TNFA. The various nuclear populations dramatically differentially expressed transcripts encoding chromatin remodeler proteins regulating DNA cytosine methylation and hydroxymethylation (TETs, DNMTs, TDG, GADD45s) and nucleosomal histone modification (ARID1A, KAT2B, KDM4A, PRMT1, PRMT5, PAXIP1). Remarkably, MSA and MVA nuclei expressed 200 to 1000-fold higher levels of thermogenic marker transcripts PRDM16 and UCP1. CONCLUSIONS: The MA-INTACT mouse enables a simple way to perform cell-type specific analysis of highly purified mature adipocyte nuclei from VAT and SAT and increases the statistical significance of data collected on adipocytes. Isolated VAT and SAT adipocyte nuclei expressed distinct patterns of transcripts encoding chromatin remodeling factors and proteins relevant to diabetes, cardiovascular disease, and thermogenesis. The MA-INTACT mouse is an useful model to test the impact of caloric intake, dietary nutrients, exercise, and pharmaceuticals on the epigenome-induced health risks of obesity.

3.
J Immunol Methods ; 436: 1-15, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27164004

RESUMO

BACKGROUND: Peripheral blood leukocytes are the most commonly used surrogates to study epigenome-induced risk and epigenomic response to disease-related stress. We considered the hypothesis that the various classes of peripheral leukocytes differentially regulate the synthesis of 5-methylcytosine (5mCG) and its removal via Ten-Eleven Translocation (TET) dioxygenase catalyzed hydroxymethylation to 5-hydroxymethylcytosine (5hmCG), reflecting their responsiveness to environment. Although it is known that reductions in TET1 and/or TET2 activity lead to the over-proliferation of various leukocyte precursors in bone marrow and in development of chronic myelomonocytic leukemia and myeloproliferative neoplasms, the role of 5mCG hydroxymethylation in peripheral blood is less well studied. RESULTS: We developed simplified protocols to rapidly and reiteratively isolate non-overlapping leukocyte populations from a single small sample of fresh or frozen whole blood. Among peripheral leukocyte types we found extreme variation in the levels of transcripts encoding proteins involved in cytosine methylation (DNMT1, 3A, 3B), the turnover of 5mC by demethylation (TET1, 2, 3), and DNA repair (GADD45A, B, G) and in the global and gene-region-specific levels of DNA 5hmCG (CD4+ T cells≫CD14+ monocytes>CD16+ neutrophils>CD19+ B cells>CD56+ NK cells>Siglec8+ eosinophils>CD8+ T cells). CONCLUSIONS: Our data taken together suggest a potential hierarchy of responsiveness among classes of leukocytes with CD4+, CD8+ T cells and CD14+ monocytes being the most distinctly poised for a rapid methylome response to physiological stress and disease.


Assuntos
5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Separação Celular/métodos , Metilação de DNA , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Linfócitos B/citologia , Epigênese Genética , Humanos , Linfócitos T/citologia
4.
PLoS One ; 11(5): e0154949, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27171244

RESUMO

The reprogramming of cellular memory in specific cell types, and in visceral adipocytes in particular, appears to be a fundamental aspect of obesity and its related negative health outcomes. We explored the hypothesis that adipose tissue contains epigenetically distinct subpopulations of adipocytes that are differentially potentiated to record cellular memories of their environment. Adipocytes are large, fragile, and technically difficult to efficiently isolate and fractionate. We developed fluorescence nuclear cytometry (FNC) and fluorescence activated nuclear sorting (FANS) of cellular nuclei from visceral adipose tissue (VAT) using the levels of the pan-adipocyte protein, peroxisome proliferator-activated receptor gamma-2 (PPARg2), to distinguish classes of PPARg2-Positive (PPARg2-Pos) adipocyte nuclei from PPARg2-Negative (PPARg2-Neg) leukocyte and endothelial cell nuclei. PPARg2-Pos nuclei were 10-fold enriched for most adipocyte marker transcripts relative to PPARg2-Neg nuclei. PPARg2-Pos nuclei showed 2- to 50-fold higher levels of transcripts encoding most of the chromatin-remodeling factors assayed, which regulate the methylation of histones and DNA cytosine (e.g., DNMT1, TET1, TET2, KDM4A, KMT2C, SETDB1, PAXIP1, ARID1A, JMJD6, CARM1, and PRMT5). PPARg2-Pos nuclei were large with decondensed chromatin. TAB-seq demonstrated 5-hydroxymethylcytosine (5hmC) levels were remarkably dynamic in gene bodies of various classes of VAT nuclei, dropping 3.8-fold from the highest quintile of expressed genes to the lowest. In short, VAT-derived adipocytes appear to be more actively remodeling their chromatin than non-adipocytes.


Assuntos
5-Metilcitosina/análogos & derivados , Núcleo Celular/metabolismo , Gordura Intra-Abdominal/citologia , Gordura Intra-Abdominal/metabolismo , 5-Metilcitosina/metabolismo , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Sequência de Bases , Biomarcadores/metabolismo , Ciclo Celular , Cromatina/metabolismo , DNA/metabolismo , Citometria de Fluxo , Imunofluorescência , Perfilação da Expressão Gênica , PPAR gama/metabolismo , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sus scrofa
6.
PLoS One ; 10(9): e0138344, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26390217

RESUMO

Beta-adrenergic activation stimulates uncoupling protein 1 (UCP1), enhancing metabolic rate. In vitro, most work has studied brown adipocytes, however, few have investigated more established adipocyte lines such as the murine 3T3-L1 line. To assess the effect of beta-adrenergic activation, mature 3T3-L1s were treated for 6 or 48 hours with or without isoproterenol (10 and 100 µM) following standard differentiation supplemented with thyroid hormone (T3; 1 nM). The highest dose of isoproterenol increased lipid content following 48 hours of treatment. This concentration enhanced UCP1 mRNA and protein expression. The increase in UCP1 following 48 hours of isoproterenol increased oxygen consumption rate. Further, coupling efficiency of the electron transport chain was disturbed and an enhancement of glycolytic rate was measured alongside this, indicating an attempt to meet the energy demands of the cell. Lastly, markers of beige adipocytes (protein content of CD137 and gene transcript of CITED1) were also found to be upregulated at 48 hours of isoproterenol treatment. This data indicates that mature 3T3-L1 adipocytes are responsive to isoproterenol and induce UCP1 expression and activity. Further, this finding provides a model for further pharmaceutical and nutraceutical investigation of UCP1 in 3T3-L1s.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Glicólise/efeitos dos fármacos , Canais Iônicos/genética , Isoproterenol/farmacologia , Proteínas Mitocondriais/genética , Células 3T3-L1 , Adipócitos/citologia , Animais , Camundongos , RNA Mensageiro/genética , Proteína Desacopladora 1 , Regulação para Cima/efeitos dos fármacos
7.
BMC Neurosci ; 16: 51, 2015 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-26260473

RESUMO

BACKGROUND: Recent evidence identifies the hippocampus, a brain structure commonly associated with learning and memory, as key to the regulation of food intake and the development and consequences of obesity. Intake of a high fat diet (HFD) results in altered consumptive behavior, hippocampal damage, and cognitive deficits. While many studies report the effects of HFD after chronic consumption and in the instance of obesity, few examine the events that occur following acute HFD consumption. In this study, male rats were fed either a control diet (10% fat by kcal) or HFD (45% fat by kcal) for 72 h. At the end of the 72-h period, serum and tissues were collected and weighed. Brains were rapidly frozen or formalin-fixed in preparation for qRT-PCR or immunohistochemistry, respectively. RESULTS: Acute intake of HFD resulted in higher serum levels of leptin and cholesterol, with no significant changes in final body weight or adipose tissue mass. In the dorsal hippocampus, transcription of the neuroprotective peptide galanin was significantly upregulated along with a trend for an increase in brain-derived neurotrophic factor and histone deacetylase 2 in the rats fed HFD. In the ventral hippocampus, there was a significant increase in histone deacetylase 4 and a decrease in galanin receptor 1 in this group. Results from immunohistochemistry validate strong presence of the galanin peptide in the CA1/CA2 region of the dorsal hippocampus. CONCLUSIONS: These results provide evidence for a distinct response in specific functional regions of the hippocampus following acute HFD intake.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Galanina/metabolismo , Hipocampo/metabolismo , Tecido Adiposo/patologia , Tecido Adiposo/fisiologia , Animais , Peso Corporal/fisiologia , Colesterol/sangue , Ingestão de Alimentos/fisiologia , Ensaio de Imunoadsorção Enzimática , Expressão Gênica , Imuno-Histoquímica , Leptina/sangue , Masculino , Tamanho do Órgão , Ratos Long-Evans , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo
8.
Obesity (Silver Spring) ; 23(1): 112-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25451038

RESUMO

OBJECTIVE: Menopausal reduction in estrogen causes increased adipose accumulation, leading many to turn to dietary supplements to prevent and treat such changes. Enhanced adipose mobilization stimulated by some supplements can increase the risk of non-alcoholic fatty liver disease (NAFLD). Cytoprotective and anti-obesity compounds may prevent the lipotoxicity associated with mobilization. METHODS: A phytochemical blend was tested in aged, ovariectomized rats. Rats were given the AIN-93M basal diet or a diet containing varying doses of phytochemicals with 2.4 IU/g vitamin D [diet 1: 1000 mg/kg genistein (G); diet 2: 500 mg/kg (G), 200 mg/kg resveratrol (R), and 1000 mg/kg quercetin (Q); diet 3: 1000 mg/kg (G), 400 mg/kg (R), and 2000 mg/kg (Q)]. RESULTS: Serum free fatty acids and hepatic triglycerides were elevated with diets 2 and 3. Despite this increase, the phytochemical blends did not increase apoptotic, cell repair, or remodeling gene expression. The highest phytochemical dose prevented increases in serum alanine aminotransferase. CONCLUSIONS: Adverse hepatic effects secondary to ovariectomy were mitigated through the inclusion of a dietary phytochemical blend in aged ovariectomized rats. The use of such compounds may not only help with weight management and disease risk in menopausal women, but may also prevent the lipotoxicity in NAFLD.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Dieta , Fígado Gorduroso/prevenção & controle , Metabolismo dos Lipídeos/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Adiposidade/efeitos dos fármacos , Animais , Suplementos Nutricionais , Fígado Gorduroso/metabolismo , Feminino , Genisteína/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Obesidade/complicações , Obesidade/dietoterapia , Obesidade/metabolismo , Ovariectomia , Ratos , Ratos Endogâmicos F344 , Triglicerídeos/metabolismo
9.
Int J Sport Nutr Exerc Metab ; 25(2): 136-44, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25029040

RESUMO

Assessment of physical activity in clinical bone studies is essential. Two bone-specific physical activity scoring methods, the Bone Loading History Questionnaire (BLHQ) and Bone-Specific Physical Activity Questionnaire (BPAQ), have shown correlations with bone density and geometry, but not architecture. The purpose of this study was to determine relationships between physical activity scoring methods and bone architecture in non-Hispanic white adolescent females (N = 24; 18-19 years of age). Bone loading scores (BLHQ [hip and spine] and past BPAQ) and energy expenditure (7-day physical activity recall) were determined from respective questionnaires. Estimates of trabecular and cortical bone architecture at the nondominant radius and tibia were assessed via magnetic resonance imaging. Total body and regional areal bone mineral density (aBMD), as well as total body fat mass and fat-free soft tissue (FFST) mass were assessed via dual energy X-ray absorptiometry. Pearson's correlations and partial correlations adjusting for height, total body fat mass, and FFST were performed. Hip BLHQ scores were correlated with midtibia cortical volume (r = .43; p = .03). Adjusted hip and spine BLHQ scores were correlated with all midtibia cortical measures (r = .50-0.58; p < .05) and distal radius apparent trabecular number (r = .46-0.53; p < .05). BPAQ scores were correlated with all midtibia cortical (r = .41-0.51; p < .05) and most aBMD (r = .47-0.53; p < .05) measures. Energy expenditure was inversely associated with femoral neck aBMD only after statistical adjustment (r = .49, p < .05). These data show that greater load-specific physical activity scores, but not energy expenditure, are indicative of greater midtibia cortical bone quality, thus supporting the utility of these instruments in musculoskeletal research.


Assuntos
Metabolismo Energético , Exercício Físico , Tíbia , Suporte de Carga , Absorciometria de Fóton , Adolescente , Adulto , Densidade Óssea , Feminino , Fêmur , Quadril , Humanos , Perna (Membro) , Imageamento por Ressonância Magnética/métodos , Esforço Físico , Coluna Vertebral , Esportes , Tíbia/anatomia & histologia , Tíbia/crescimento & desenvolvimento , População Branca , Adulto Jovem
10.
Nutr Res ; 34(1): 66-73, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24418248

RESUMO

Human clinical trials targeted at preventing gains in body weight using soy protein and isoflavones are limited to adults and yield conflicting results. We hypothesized that daily intake of soy protein/isoflavones would attenuate gains in body weight to a greater extent than a casein-based control in 18 to 19 year-old females. To test this hypothesis, we conducted a randomized, double blind, placebo-controlled trial over 16 weeks to examine the effects of a soy protein/isoflavone-based meal replacement (experimental group) versus a casein-based meal replacement (control group) on body weight and body composition variables in female college freshmen (N = 120). Fat mass (FM), fat-free soft tissue mass (FFST), and percent body fat (%BF) were measured using dual energy X-ray absorptiometry (DXA; Delphi A). Repeated measures mixed models were used to determine the effects of treatment on anthropometric and body composition variables (body weight, waist circumference, FM, FFST, and %BF). No significant group×time interactions were observed, even when body mass index was controlled for in the analysis. Over 16 weeks, body weight, FM, FFST, and %BF significantly increased in both groups (P < .05). Our findings show that female college freshmen gained a significant amount of weight over the course of the 16-week study. Gains in body weight and FM were similar among participants assigned to the soy protein/isoflavone- and the casein-based meal replacements. Future research is warranted to determine the effects of soy protein/isoflavone- and casein-based meal replacements versus a non-intervention (i.e., non-protein based) control.


Assuntos
Isoflavonas/administração & dosagem , Proteínas de Soja/administração & dosagem , Aumento de Peso , Absorciometria de Fóton , Adolescente , Composição Corporal , Índice de Massa Corporal , Caseínas/administração & dosagem , Dieta , Método Duplo-Cego , Exercício Físico , Feminino , Humanos , Placebos , Proteínas de Soja/química , Estudantes , Circunferência da Cintura
11.
Nutr Res ; 34(1): 85-93, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24418250

RESUMO

High-fat diets (HFD) promote the development of both obesity and fatty liver disease through the up-regulation of hepatic lipogenesis. Insulin resistance, a hallmark of both conditions, causes dysfunctional fuel partitioning and increases in lipogenesis. Recent work has demonstrated that systemic insulin resistance occurs in as little as the first 72 hours of an HFD, suggesting the potential for hepatic disruption with HFD at this time point. The current study sought to determine differences in expression of lipogenic genes between sexes in 3-month-old male and female Long-Evans rats after 72 hours of a 40% HFD or a 17% fat (chow) diet. Owing to the response of estrogen on hepatic signaling, we hypothesized that a sexual dimorphic response would occur in the expression of lipogenic enzymes, inflammatory cytokines, apoptotic, and cell repair and remodeling genes. Both sexes consumed more energy when fed an HFD compared with their low fat-fed controls. However, only the males fed the HFD had a significant increase in body fat. Regardless of sex, HFD caused down-regulation of lipogenic and inflammatory genes. Interestingly, females fed an HFD had up-regulated expression of apoptotic and cell repair-related genes compared with the males. This may suggest that females are more responsive to the acute hepatic injury effects caused by HFDs. In summary, neither male nor female rats displayed disrupted hepatic metabolic pathways after 72 hours of the HFD treatment. In addition, female rats appear to have protection from increases in fat deposition, possibly due to increased caloric expenditure; male rats fed an HFD were less active, as demonstrated by distance traveled in their home cage.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica , Inflamação/genética , Lipogênese/genética , Fígado/metabolismo , Animais , Apoptose/genética , Composição Corporal , Proteínas de Ligação a DNA/genética , Ingestão de Energia , Feminino , Masculino , Esforço Físico , Ratos , Ratos Long-Evans , Fatores de Transcrição de Fator Regulador X , Fatores Sexuais , Transdução de Sinais/genética , Fatores de Transcrição/genética , Aumento de Peso , Proteína 1 de Ligação a X-Box
12.
Nutr Res ; 33(12): 1063-71, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24267046

RESUMO

Optimization of peak bone mass during adolescence is important for osteoporosis prevention. Studies in rodents and humans have demonstrated the harmful effects of sugar intake on bone health. With the high levels of sucrose in the diets of adolescents, it is necessary to understand the influence of glucose and fructose on growing bones. This study compared the effects of dietary glucose and fructose on bone formation, microarchitecture, and strength. Because of the different metabolic effects of glucose and fructose, we hypothesized that their individual effects on bone would be different. Eighteen male Sprague-Dawley rats (age, 60 days) were randomly assigned to high-fructose (n = 9; 40% fructose, 10% glucose) or high-glucose diet (n = 9; 50% glucose) for 12 weeks. Bone measurements included histology and histomorphometry of trabecular bone in the distal femur and a 3-point bending test of the whole tibia. Whole liver mass and postprandial serum glucose, insulin, and triglycerides were used to assess differences in energy metabolism between the diets. There were no differences in food intake, body weight, or visceral adiposity between groups, but fructose consumption led to heavier livers (P = .001) and elevated serum triglycerides (P = .00). The distal femurs of fructose-fed rats had greater bone volume (bone volume/total volume; P = .03), lower bone surface (bone surface/bone volume; P = .02), and thicker trabeculae (trabecular thickness; P = .01). The tibias of the fructose-fed rats also withstood a greater maximum flexure load (P = .032). These results indicate that consumption of the high-fructose diet resulted in stronger bones with enhanced microarchitecture than consumption of the high-glucose diet.


Assuntos
Osso e Ossos/efeitos dos fármacos , Dieta , Metabolismo Energético/efeitos dos fármacos , Frutose/farmacologia , Glucose/farmacologia , Osteogênese/efeitos dos fármacos , Osteoporose/prevenção & controle , Animais , Composição Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/metabolismo , Carboidratos da Dieta/farmacologia , Ingestão de Energia , Fêmur/efeitos dos fármacos , Frutose/metabolismo , Glucose/metabolismo , Fígado/efeitos dos fármacos , Masculino , Obesidade/metabolismo , Obesidade/prevenção & controle , Tamanho do Órgão/efeitos dos fármacos , Osteoporose/metabolismo , Ratos , Ratos Sprague-Dawley , Tíbia/efeitos dos fármacos , Triglicerídeos/sangue
13.
Cell Tissue Res ; 354(3): 743-50, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24026435

RESUMO

The bioactive flavonoid p-hydroxycinnamic acid (HCA), which is an intermediate-metabolic substance in plants and fruits, is synthesized from tyrosine. The biological effect of HCA is poorly understood. Among cinnamic acid and its related compounds, HCA has a specific-anabolic effect on bone, being found to stimulate osteoblastogenesis and to inhibit osteoclastogenesis through the suppression of NF-κB signaling, thereby preventing bone loss. Bone marrow mesenchymal stem cells give rise to ostoblasts and adipocytes. HCA might therefore have effects on osteoblastogenesis and adipogenesis in bone marrow culture. This study demonstrates (1) that HCA has stimulatory effects on osteoblastogenesis and mineralization and suppressive effects on adipogenesis in mouse bone marrow culture and (2) that HCA depresses adipogenesis in mouse 3T3-L1 preadipocytes in vitro. Such effects of HCA might be involved in the differentiation of mesenchymal stem cells.


Assuntos
Adipogenia/efeitos dos fármacos , Células da Medula Óssea/efeitos dos fármacos , Ácidos Cumáricos/farmacologia , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Animais , Células da Medula Óssea/citologia , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/citologia , Propionatos , Estimulação Química
14.
J Bone Miner Res ; 28(3): 489-96, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23296755

RESUMO

Adenovirus 36 (Ad36) is the only adenovirus to date that has been linked with obesity in humans. Our previous studies in late-adolescent females suggest that excess weight in the form of fat mass is associated with lower cortical bone strength. The purpose of this study was to assess the relationship between Ad36-specific antibodies, adiposity, and bone strength in our sample of late-adolescent females. A cross-sectional study of 115 females aged 18 to 19 years was performed. Participants were classified according to adiposity by dual-energy X-ray absorptiometry (body fat percentage as normal-fat [ < 32% body fat; n = 93] or high-fat [ ≥ 32% body fat; n = 22]), and according to the presence of Ad36-specific neutralizing antibodies. Peripheral quantitative computed tomography measured bone parameters at the 4% (trabecular bone) and 20% (cortical bone) site, and muscle cross-sectional area (MCSA) at the 66% site, from the distal metaphyses of the radius and the tibia. Bone strength was determined from volumetric bone mineral density and bone geometry to calculate bone strength index (BSI; trabecular site) and polar strength-strain index (SSI; cortical site). After adjustment for MCSA and limb length, radial SSI was lower in Ad36+ versus Ad36- subjects from the high-fat group (p < 0.03), but not the normal-fat group. No significant differences were observed between groups in tibial SSI or BSI. These data support an association of adiposity and cortical bone strength at the radius with the presence of neutralizing antibodies to Ad36 in late-adolescent females.


Assuntos
Adenoviridae/patogenicidade , Adiposidade , Osso e Ossos/fisiologia , Absorciometria de Fóton , Adolescente , Adulto , Feminino , Humanos , Tomografia Computadorizada por Raios X , Adulto Jovem
15.
Postdoc J ; 1(5): 27-38, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-27904876

RESUMO

Estrogens have been shown to protect against various diseases and disastrous metabolic consequences of poor diets. Although a large body of research demonstrates estrogen's ability to control food intake, adipogenesis, and oxidative stress, research regarding the effects of estrogens on hepatic lipogenesis, steatosis, and non-alcoholic fatty liver disease is only now accumulating. Estrogen deficiency in both human and rodent models directly results in the upregulation of hepatic lipogenic signaling - in both serum and hepatic triglyceride content - which leads to the development of fatty liver. In all models, estrogen replacement completely reverses these outcomes. Similar to the endogenous estrogen hormone, plant-derived phytoestrogens also appear to have beneficial effects related to prevention of hepatic lipogenic signaling and steatosis in rodent models. Additionally, such compounds can completely overcome the hepatic consequences that result from estrogen deficiency. While published research strongly supports that estrogens, both endogenous and exogenous, can protect against hepatic lipogenic signaling that can contribute to the development of non-alcoholic fatty liver diseases and adverse weight gain, little research exists on elucidating the mechanism behind this protection. Various pathways have been suggested, including manipulation of both leptin and signal transducer and activator of transcription 3 (STAT3) signaling. However, the discovery of x-box protein 1 elicits the identification of another potential pathway through which estrogen may be working. While the supportive work is strong, further research is needed to determine the mechanism behind the protection by estrogens from hepatic lipogenesis and associated diseases.

16.
Integr Biol (Camb) ; 4(10): 1215-22, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22868942

RESUMO

Regucalcin plays a pivotal role in regulating intracellular calcium homeostasis and consequently has a profound effect on multiple intracellular signal transduction pathways. The regucalcin transgenic rat displays pronounced bone loss and hyperlipidemia. Consistent with these effects exogenous regucalcin has been shown to promote osteoclastogenesis in mouse bone marrow cultures and to suppress the differentiation and mineralization of MC3T3 osteoblast precursors. Regucalcin may induce hyperlipidemia in vivo by suppressing osteoblast differentiation and stimulating adipogenesis in bone marrow mesenchymal stem cells. The present study demonstrates that exogenous regucalcin suppresses differentiation to osteoblasts and stimulates adipogenesis in mouse bone marrow cell culture ex vivo. Moreover, exogenous regucalcin was found to enhance adipogenesis stimulated by insulin which is involved in the extracellular signal-related kinase pathway in 3T3-L1 adipocytes in vitro.


Assuntos
Adipócitos/citologia , Células da Medula Óssea/citologia , Proteínas de Ligação ao Cálcio/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Osteoblastos/citologia , Células 3T3 , Adipogenia/efeitos dos fármacos , Animais , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Insulina/metabolismo , Células-Tronco Mesenquimais/citologia , Camundongos , Transdução de Sinais , Células-Tronco
17.
PLoS One ; 6(6): e19881, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21698226

RESUMO

BACKGROUND: Resveratrol is a natural compound suggested to have beneficial health effects. However, people are consuming resveratrol for this reason without having the adequate scientific evidence for its effects in humans. Therefore, scientific valid recommendations concerning the human intake of resveratrol based on available published scientific data are necessary. Such recommendations were formulated after the Resveratrol 2010 conference, held in September 2010 in Helsingør, Denmark. METHODOLOGY: Literature search in databases as PUBMED and ISI Web of Science in combination with manual search was used to answer the following five questions: (1)Can resveratrol be recommended in the prevention or treatment of human diseases?; (2)Are there observed "side effects" caused by the intake of resveratrol in humans?; (3)What is the relevant dose of resveratrol?; (4)What valid data are available regarding an effect in various species of experimental animals?; (5)Which relevant (overall) mechanisms of action of resveratrol have been documented? CONCLUSIONS/SIGNIFICANCE: The overall conclusion is that the published evidence is not sufficiently strong to justify a recommendation for the administration of resveratrol to humans, beyond the dose which can be obtained from dietary sources. On the other hand, animal data are promising in prevention of various cancer types, coronary heart diseases and diabetes which strongly indicate the need for human clinical trials. Finally, we suggest directions for future research in resveratrol regarding its mechanism of action and its safety and toxicology in human subjects.


Assuntos
Estilbenos/farmacologia , Humanos , Resveratrol , Estilbenos/administração & dosagem , Estilbenos/efeitos adversos
18.
J Med Food ; 14(11): 1352-62, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21663481

RESUMO

Vitamin D and certain natural compounds have been shown to regulate both lipid metabolism and bone formation. Treatments that prevent or reverse age-related increase in bone marrow adiposity could both increase new bone formation and inhibit bone destruction. We tested the hypothesis that dietary supplementation with combinations of vitamin D and phytochemicals inhibits bone loss and decreases adiposity to a greater extent than control or vitamin D-alone diets. Aged ovariectomized female rats (12 months old, n=50, initial body weight=240 g) were given control (AIN-93M diet), vitamin D (2,400 IU/kg), or vitamin D plus resveratrol (16, 80, or 400 mg/kg of diet [low, medium, and high dose, respectively]), quercetin (80, 400, or 2,000 mg/kg of diet), and genistein (64, 256, or 1,040 mg/kg of diet) for 8 weeks. The high-dose treatment (vitamin D+400 mg/kg resveratrol+2,000 mg/kg quercetin+1,040 mg/kg genistein) reduced body weight gain (P<.05) and the fat pad weights (P<.05). This treatment also increased the serum concentration of insulin-like growth factor-1 (P<.05) and the bone mineral content of the femur. Micro-computed tomography and histomorphometric analyses indicated that the high-dose treatment prevented loss of trabecular bone (P<.05) and reduced marrow adipocytes (P<.001) and osteoclasts (P<.05) compared with the control and vitamin D alone (P<.05). We conclude that aged ovariectomized female rats supplemented with vitamin D combined with genistein, quercetin, and resveratrol had improved bone mineral density and reduced body weight gain and a significant decrease in bone marrow adipocytes. The synergistic effects of a combination of phytochemicals with vitamin D may be effective in reducing bone loss and weight gain after menopause.


Assuntos
Doenças Ósseas Metabólicas/prevenção & controle , Suplementos Nutricionais , Combinação de Medicamentos , Fitoterapia/métodos , Vitamina D/administração & dosagem , Aumento de Peso/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Adiposidade/efeitos dos fármacos , Animais , Densidade Óssea/efeitos dos fármacos , Dieta , Feminino , Fêmur/efeitos dos fármacos , Genisteína/administração & dosagem , Ovariectomia , Quercetina/administração & dosagem , Ratos , Ratos Endogâmicos F344 , Resveratrol , Estilbenos/administração & dosagem
19.
Recent Pat Anticancer Drug Discov ; 6(3): 367-72, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21612576

RESUMO

Since tumors cannot grow or spread without forming new blood vessels, inhibiting angiogenesis is an excellent approach for the treatment of cancer. Further, inhibitors of angiogenesis have mild side effects since they act on endothelial cells, which eliminate the possibility of developing resistance or tolerance in tumor cells, unlike that seen with chemotherapy drugs. The anti-vascular endothelial growth factor (VEGF) monoclonal antibody bevacizumab acts by preventing new blood vessel formation in solid tumors and is approved by FDA to treat colorectal, lung, breast, glioblastoma and kidney cancers. The registration of this drug and its ongoing success in the clinic has validated the targeting of angiogenesis as an important approach to the treatment of solid tumors. Apelin is a novel angiogenic factor and recent studies indicate that apelin promotes angiogenesis, lymphangiogenesis and tumor growth in vivo and the angiogenic potential of apelin is similar to that of VEGF. Also, apelin expression is upregulated and has been shown to be associated with clinical outcome in certain human cancers. Thus, inhibition of apelin activity might lead to a new class of anti-angiogenesis drugs which should be more efficacious than those currently on the market due to their ability to be both anti-angiogenic as well as anti-lymphangiogenic. There are very few patents on the angiogenic effects of apelin and this review article focuses on these patented claims related to inhibiting apelin signaling and sheds more light on how blocking apelin signaling might open doors to a new class of angiogenic inhibitors.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Neoplasias/tratamento farmacológico , Patentes como Assunto , Inibidores da Angiogênese/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Apelina , Feminino , Humanos , Modelos Biológicos
20.
Mol Nutr Food Res ; 55(8): 1177-85, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21538845

RESUMO

Resveratrol, a phytoalexin, has gained much attention recently due to its effects on sirtuins. While the anti-cancer properties of resveratrol have been extensively investigated, the anti-adipogenic and osteogenic effects of resveratrol are also gaining considerable interest. The finding that resveratrol supplementation mimics caloric restriction prompted researchers to study the effects of resveratrol on lipid metabolism. Mesenchymal stem cells are the precursors for both adipocytes and osteoblasts. In the aging population, differentiation to adipocytes dominates over the differentiation to osteoblasts in bone marrow, contributing to the increased tendency for fractures to occur in the elderly. Thus, an inverse relationship exists between adipocytes and osteoblasts in the bone marrow. Resveratrol acts on several molecular targets in adipocytes and osteoblasts leading to a decrease in adipocyte number and size and an increase in osteogenesis. Furthermore, resveratrol in combination with genistein and quercetin synergistically decreased adipogenesis in murine and human adipocytes. A recent in vivo study showed that phytochemicals including resveratrol in combination with vitamin D prevented weight gain and bone loss in a postmenopausal rat model. Therefore, combinations of resveratrol with other phytochemicals may lead to potential novel potent therapies for both obesity and osteoporosis.


Assuntos
Obesidade/tratamento farmacológico , Osteoporose/tratamento farmacológico , Estilbenos/uso terapêutico , Adipócitos/efeitos dos fármacos , Adipócitos/fisiologia , Animais , Restrição Calórica , Sinergismo Farmacológico , Humanos , Lipólise/efeitos dos fármacos , Osteoblastos/fisiologia , Resveratrol , Estilbenos/farmacologia
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