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1.
Front Endocrinol (Lausanne) ; 14: 1280539, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38239980

RESUMO

Background: A steady rise in type 2 diabetes (T2D) in Mexico over the last 30 years has led to 11.5 million Mexicans being affected by this condition. There is an urgent need to develop interventions to prevent complications of T2D. Diabetes self-management education is the cornerstone of promoting self-care. Among all educational strategies, peer support has shown to be an effective method to encourage ongoing self-management. However, customization of interventions for distinct communities is imperative, as failure to do so can hinder the intervention's effectiveness. Methods: We implemented a two-year prospective randomized controlled community-based trial in Conkal, a Mayan community from Yucatan, Mexico. The intervention consisted of receiving either a culturally sensitive peer support on top of a diabetes self-management education group (PLG); or a diabetes self-management education group only (EOG; control group). The primary outcome was changes in glycated hemoglobin, while secondary outcomes encompassed changes in systolic and diastolic blood pressure, body mass index, and diabetes self-care practices. Data collection was performed at baseline and every four months during the study period. Discussion: Our experiences have highlighted the significance of peer-leader support in cultivating diabetes self-care skills, particularly within smaller, underserved communities characterized by strong social and cultural ties. However, when applied in larger or suburban settings, selecting peer leaders should be meticulous, considering sectorization within specific neighborhoods to foster a sense of belonging and familiarity among natural community clusters. In larger settlemnts, factors such as transportation challenges, time limitations, caregiving obligations, limited venue access, and changes in session locations can drive program discontinuation. Additionally, individuals with lower educational attainment are more susceptible to abandonment. Notably, those with lower education, uncontrolled diabetes, and extended diabetes duration exhibit a greater potential for improving glycemic control than their counterparts. Clinical registration: https://www.isrctn.com/ISRCTN96897082.


Assuntos
Diabetes Mellitus Tipo 2 , População norte-americana , Humanos , Estudos Prospectivos , Apoio Social , Aconselhamento/métodos
2.
Biology (Basel) ; 10(12)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34943258

RESUMO

We previously reported preliminary characterization of adipose tissue (AT) dysfunction through the adiponectin/leptin ratio (ALR) and fasting/postprandial (F/P) gene expression in subcutaneous (SQ) adipose tissue (AT) biopsies obtained from participants in the GEMM study, a precision medicine research project. Here we present integrative data replication of previous findings from an increased number of GEMM symptom-free (SF) adults (N = 124) to improve characterization of early biomarkers for cardiovascular (CV)/immunometabolic risk in SF adults with AT dysfunction. We achieved this goal by taking advantage of the rich set of GEMM F/P 5 h time course data and three tissue samples collected at the same time and frequency on each adult participant (F/P blood, biopsies of SQAT and skeletal muscle (SKM)). We classified them with the presence/absence of AT dysfunction: low (<1) or high (>1) ALR. We also examined the presence of metabolically healthy (MH)/unhealthy (MUH) individuals through low-grade chronic subclinical inflammation (high sensitivity C-reactive protein (hsCRP)), whole body insulin sensitivity (Matsuda Index) and Metabolic Syndrome criteria in people with/without AT dysfunction. Molecular data directly measured from three tissues in a subset of participants allowed fine-scale multi-OMIC profiling of individual postprandial responses (RNA-seq in SKM and SQAT, miRNA from plasma exosomes and shotgun lipidomics in blood). Dynamic postprandial immunometabolic molecular endophenotypes were obtained to move towards a personalized, patient-defined medicine. This study offers an example of integrative translational research, which applies bench-to-bedside research to clinical medicine. Our F/P study design has the potential to characterize CV/immunometabolic early risk detection in support of precision medicine and discovery in SF individuals.

3.
Small ; 17(31): e2008177, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34185956

RESUMO

Ultrasound-targeted microbubble destruction (UTMD) mediates gene transfection with high biosafety and thus has been promising toward treatment of type 1 diabetes. However, the potential application of UTMD in type 2 diabetes (T2D) is still limited, due to the lack of systematic design and dynamic monitoring. Herein, an efficient gene delivery system is constructed by plasmid deoxyribonucleic acid (DNA) encoding glucagon-like peptide 1 (GLP-1) in ultrasound-induced microbubbles, toward treatment of T2D in macaque. The as designed UTMD afforded enhancement of cell membrane penetration and GLP-1 expression in macaque, which is characterized by ultrasound-guided biopsy to monitor the dynamic process of islet cells for 6 months. Also, improvement of pancreatic beta cell regeneration, and regulation of plasma glucose in macaque with T2D is achieved. The approach would serve as promising alternatives for the treatment of T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Técnicas de Transferência de Genes , Glucose , Humanos , Microbolhas , Regeneração , Transfecção
4.
Res Vet Sci ; 133: 136-145, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32979746

RESUMO

A large number of studies have shown that the baboon is one of the most commonly used non-human primate (NHP) research model for the study of immunometabolic complex traits such as type 2 diabetes (T2D), insulin resistance (IR), adipose tissue dysfunction (ATD), dyslipidemia, obesity (OB) and cardiovascular disease (CVD). This paper reports on innovative technologies and advanced research strategies for energetics and translational medicine with this NHP model. This includes the following: measuring resting energy expenditure (REE) with the mobile indirect calorimeter Breezing®; monitoring daily body temperature using subcutaneously implanted data loggers; quantifying metabolic heat with veterinary infrared thermography (IRT) imaging, and non-viral non-invasive, tissue-specific ultrasound-targeted microbubble destruction (UTMD) gene-based therapy. These methods are of broad utility; for example, they may facilitate the engineering of ectopic overexpression of brown adipose tissue (BAT) mUCP-1 via UTMD-gene therapy into baboon SKM to achieve weight loss, hypophagia and immunometabolic improvement. These methods will be valuable to basic and translational research, and human clinical trials, in the areas of metabolism, cardiovascular health, and immunometabolic and infectious diseases.


Assuntos
Temperatura Corporal , Metabolismo Energético , Terapia Genética/veterinária , Monitorização Fisiológica/veterinária , Papio/fisiologia , Projetos de Pesquisa , Animais , Modelos Animais de Doenças , Terapia Genética/métodos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Termografia/veterinária
6.
Pathogens ; 9(5)2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32438687

RESUMO

An altered immune response to pathogens has been suggested to explain increased susceptibility to infectious diseases in patients with diabetes. Recent evidence has documented several immunometabolic pathways in patients with diabetes directly related to the COVID-19 infection. This also seems to be the case for prediabetic subjects with proinflammatory insulin resistance syndrome accompanied with prothrombotic hyperinsulinemic and dysglycemic states. Patients with frank hyperglycemia, dysglycemia and/or hyperinsulinemia develop systemic immunometabolic inflammation with higher levels of circulating cytokines. This deleterious scenario has been proposed as the underlying mechanism enhancing a cytokine storm-like hyperinflammatory state in diabetics infected with severe COVID-19 triggering multi-organ failure. Compared with moderately affected COVID-19 patients, diabetes was found to be highly prevalent among severely affected patients suggesting that this non-communicable disease should be considered as a risk factor for adverse outcomes. The COVID-19 pandemic mirrors with the diabetes pandemic in many pathobiological aspects. Our interest is to emphasize the ties between the immunoinflammatory mechanisms that underlie the morbidity and lethality when COVID-19 meets diabetes. This review brings attention to two pathologies of highly complex, multifactorial, developmental and environmentally dependent manifestations of critical importance to human survival. Extreme caution should be taken with diabetics with suspected symptoms of COVID-19 infection.

7.
Adipocyte ; 9(1): 153-169, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32272872

RESUMO

Interactions between macrophages and adipocytes are early molecular factors influencing adipose tissue (AT) dysfunction, resulting in high leptin, low adiponectin circulating levels and low-grade metaflammation, leading to insulin resistance (IR) with increased cardiovascular risk. We report the characterization of AT dysfunction through measurements of the adiponectin/leptin ratio (ALR), the adipo-insulin resistance index (Adipo-IRi), fasting/postprandial (F/P) immunometabolic phenotyping and direct F/P differential gene expression in AT biopsies obtained from symptom-free adults from the GEMM family study. AT dysfunction was evaluated through associations of the ALR with F/P insulin-glucose axis, lipid-lipoprotein metabolism, and inflammatory markers. A relevant pattern of negative associations between decreased ALR and markers of systemic low-grade metaflammation, HOMA, and postprandial cardiovascular risk hyperinsulinemic, triglyceride and GLP-1 curves was found. We also analysed their plasma non-coding microRNAs and shotgun lipidomics profiles finding trends that may reflect a pattern of adipose tissue dysfunction in the fed and fasted state. Direct gene differential expression data showed initial patterns of AT molecular signatures of key immunometabolic genes involved in AT expansion, angiogenic remodelling and immune cell migration. These data reinforce the central, early role of AT dysfunction at the molecular and systemic level in the pathogenesis of IR and immunometabolic disorders.


Assuntos
Tecido Adiposo/metabolismo , Medicina de Precisão , Adulto , Estudos de Coortes , Jejum , Feminino , Humanos , Resistência à Insulina , Lipídeos/sangue , Masculino , Fenótipo , Fatores de Risco
8.
JCI Insight ; 4(20)2019 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-31536476

RESUMO

The glucagon-like peptide-1 receptor agonist exenatide improves glycemic control by several and not completely understood mechanisms. Herein, we examined the effects of chronic intravenous exenatide infusion on insulin sensitivity, ß cell and α cell function and relative volumes, and islet cell apoptosis and replication in nondiabetic nonhuman primates (baboons). At baseline, baboons received a 2-step hyperglycemic clamp followed by an l-arginine bolus (HC/A). After HC/A, baboons underwent a partial pancreatectomy (tail removal) and received a continuous exenatide (n = 12) or saline (n = 12) infusion for 13 weeks. At the end of treatment, HC/A was repeated, and the remnant pancreas (head-body) was harvested. Insulin sensitivity increased dramatically after exenatide treatment and was accompanied by a decrease in insulin and C-peptide secretion, while the insulin secretion/insulin resistance (disposition) index increased by about 2-fold. ß, α, and δ cell relative volumes in exenatide-treated baboons were significantly increased compared with saline-treated controls, primarily as the result of increased islet cell replication. Features of cellular stress and secretory dysfunction were present in islets of saline-treated baboons and absent in islets of exenatide-treated baboons. In conclusion, chronic administration of exenatide exerts proliferative and cytoprotective effects on ß, α, and δ cells and produces a robust increase in insulin sensitivity in nonhuman primates.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Exenatida/farmacologia , Hipoglicemiantes/farmacologia , Resistência à Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Glicemia/análise , Proliferação de Células/efeitos dos fármacos , Transdiferenciação Celular/efeitos dos fármacos , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/patologia , Modelos Animais de Doenças , Exenatida/uso terapêutico , Feminino , Técnica Clamp de Glucose , Humanos , Hipoglicemiantes/uso terapêutico , Infusões Intravenosas , Insulina/metabolismo , Ilhotas Pancreáticas/patologia , Masculino , Papio
9.
Genes (Basel) ; 10(5)2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067764

RESUMO

BACKGROUND: Congenital leptin deficiency is a recessive genetic disorder associated with severe early-onset obesity. It is caused by mutations in the leptin (LEP) gene, which encodes the protein product leptin. These mutations may cause nonsense-mediated mRNA decay, defective secretion or the phenomenon of biologically inactive leptin, but typically lead to an absence of circulating leptin, resulting in a rare type of monogenic extreme obesity with intense hyperphagia, and serious metabolic abnormalities. METHODS: We present two severely obese sisters from Colombia, members of the same lineal consanguinity. Their serum leptin was measured by MicroELISA. DNA sequencing was performed on MiSeq equipment (Illumina) of a next-generation sequencing (NGS) panel involving genes related to severe obesity, including LEP. RESULTS: Direct sequencing of the coding region of LEP gene in the sisters revealed a novel homozygous missense mutation in exon 3 [NM_002303.3], C350G>T [p.C117F]. Detailed information and clinical measurements of these sisters were also collected. Their serum leptin levels were undetectable despite their markedly elevated fat mass. CONCLUSIONS: The mutation of LEP, absence of detectable leptin, and the severe obesity found in these sisters provide the first evidence of monogenic leptin deficiency reported in the continents of North and South America.


Assuntos
Leptina/genética , Mutação de Sentido Incorreto/genética , Obesidade Mórbida/genética , Adulto , Colômbia , Consanguinidade , Éxons/genética , Feminino , Humanos , Leptina/deficiência , Obesidade Mórbida/fisiopatologia , Linhagem , Irmãos
10.
Genes (Basel) ; 9(11)2018 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-30400254

RESUMO

Cardiovascular disease (CVD) and type 2 diabetes (T2D) are increasing worldwide. This is mainly due to an unhealthy nutrition, implying that variation in CVD risk may be due to variation in the capacity to manage a nutritional load. We examined the genomic basis of postprandial metabolism. Our main purpose was to introduce the GEMM Family Study (Genetics of Metabolic Diseases in Mexico) as a multi-center study carrying out an ongoing recruitment of healthy urban adults. Each participant received a mixed meal challenge and provided a 5-hours' time course series of blood, buffy coat specimens for DNA isolation, and adipose tissue (ADT)/skeletal muscle (SKM) biopsies at fasting and 3 h after the meal. A comprehensive profiling, including metabolomic signatures in blood and transcriptomic and proteomic profiling in SKM and ADT, was performed to describe tendencies for variation in postprandial response. Our data generation methods showed preliminary trends indicating that by characterizing the dynamic properties of biomarkers with metabolic activity and analyzing multi-OMICS data it could be possible, with this methodology and research design, to identify early trends for molecular biology systems and genes involved in the fasted and fed states.

11.
Gene Ther ; 25(7): 497-509, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30072816

RESUMO

Here we present our progress in inducing an ectopic brown adipose tissue (BAT) phenotype in skeletal muscle (SKM) as a potential gene therapy for obesity and its comorbidities. We used ultrasound-targeted microbubble destruction (UTMD), a novel targeted, non-viral approach to gene therapy, to deliver genes in the BAT differentiation pathway into rodent SKM to engineer a thermogenic BAT phenotype with ectopic mUCP-1 overexpression. In parallel, we performed a second protocol using wild-type Ucp-1-null knockout mice to test whether the effects of the gene therapy are UCP-1 dependent. Our main findings were a robust cellular presence of mUCP-1 immunostaining (IHC), significantly higher expression levels of mUCP-1 measured by qRT-PCR, and highest temperature elevation measured by infrared thermography in the treated thigh, achieved in rats after delivering the UTMD-PRDM16/PGC-1a/BMP7/hyPB gene cocktail. Interestingly, the weight loss obtained in the treated rats with the triple gene delivery, never recovered the levels observed in the controls in spite of food intake recovery. Our results establish the feasibility of minimally invasive UTMD gene-based therapy administration in SKM, to induce overexpression of ectopic mUCP-1 after delivery of the thermogenic BAT gene program, and describe systemic effects of this intervention on food intake, weight loss, and thermogenesis.


Assuntos
Tecido Adiposo Marrom/metabolismo , Terapia Genética , Obesidade/terapia , Proteína Desacopladora 1/genética , Tecido Adiposo Marrom/transplante , Animais , Ingestão de Alimentos/genética , Regulação da Expressão Gênica , Camundongos , Camundongos Knockout , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Ratos , Termogênese/genética , Proteína Desacopladora 1/administração & dosagem
12.
Surg Obes Relat Dis ; 14(6): 833-841, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29631983

RESUMO

BACKGROUND: Visceral obesity is associated with diabetogenic and atherogenic abnormalities, including insulin resistance and increased risk for cardiometabolic diseases and mortality. Rodent lipectomy studies have demonstrated a causal link between visceral fat and insulin resistance, yet human omentectomy studies have failed to replicate this metabolic benefit, perhaps owing to the inability to target the mesentery. OBJECTIVES: We aimed to demonstrate that safe and effective removal of mesenteric fat could be achieved in obese insulin-resistant baboons using tissue liquefaction technology. SETTING: Southwest National Primate Research Center, San Antonio, Texas. METHODS: Tissue liquefaction technology has been developed to enable mesenteric visceral lipectomy (MVL) to be safely performed without disturbing the integrity of surrounding nerves and vessels in the mesentary. After an initial MVL optimization study (n = 3), we then performed MVL (n = 4) or sham surgery (n = 2) in a cohort of insulin-resistant baboons, and the metabolic phenotype was assessed via hyperinsulinemic-euglycemic clamps at baseline and 6 weeks later. RESULTS: MVL led to a 75% improvement in glucose disposal at 6-weeks follow-up (P = .01). Moreover, despite removing only an average of 430 g of mesenteric fat (~1% of total body mass), MVL led to a 14.4% reduction in total weight (P = .001). Thus, these data demonstrate that mesenteric fat can be safely targeted for removal by tissue liquefaction technology in a nonhuman primate, leading to substantial metabolic improvements, including reversal of insulin resistance and weight loss. CONCLUSIONS: These data provide the first demonstration of successful adipose tissue removal from the mesentery in a mammal. Importantly, we have demonstrated that when MVL is performed in obese, insulin-resistant baboons, insulin resistance is reversed, and significant weight loss occurs. Therefore, trials performing MVL in humans with abdominal obesity and related metabolic sequelae should be explored as a potential clinical tool to ameliorate insulin resistance and treat type 2 diabetes.


Assuntos
Resistência à Insulina/fisiologia , Lipectomia/métodos , Obesidade Abdominal/cirurgia , Redução de Peso/fisiologia , Animais , Metabolismo Basal/fisiologia , Biotecnologia/métodos , Composição Corporal/fisiologia , Índice de Massa Corporal , Dieta , Hemoglobinas Glicadas/metabolismo , Gordura Intra-Abdominal/cirurgia , Metabolismo dos Lipídeos/fisiologia , Masculino , Mesentério/cirurgia , Papio , Complicações Pós-Operatórias/etiologia , Circunferência da Cintura
13.
Artigo em Inglês | MEDLINE | ID: mdl-28926971

RESUMO

Studies of gene-environment (GxE) interactions describe how genetic and environmental factors influence the risk of developing disease. Intermediate (molecular or clinical) phenotypes (IPs) are traits or metabolic biomarkers that mediate the effects of gene-environment influences on risk behaviors. Functional systems genomics discovery offers mechanistic insights into how DNA variations affect IPs in order to detect genetic causality for a given disease. Disorders of body composition include obesity (OB), Type 2 diabetes (T2D), and osteoporosis (OSTP). These pathologies are examples of how a GxE interaction contributes to their development. IPs as surrogates for inherited genotypes play a key role in models of genetic and environmental interactions in health outcomes. Such predictive models may unravel relevant genomic and molecular pathways for preventive and therapeutic interventions for OB, T2D, and OSTP. Annotation strategies for genomes, in contrast to phenomes, are well advanced. They generally do not measure specific aspects of the environment. Therefore, the concepts of deep phenotyping and the exposome generate new avenues to exploit with high-resolution technologies for analyzing this sophisticated phenome. With the successful characterization of phenomes, exposomes, and genomes, environmental and genetic determinants of chronic diseases can be united with multi-OMICS studies that better examine GxE interactions.


Assuntos
Diabetes Mellitus Tipo 2/genética , Interação Gene-Ambiente , Obesidade/genética , Osteoporose/genética , Fenótipo , Composição Corporal , Humanos
14.
IUBMB Life ; 69(9): 745-755, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28762248

RESUMO

Ultrasound-targeted microbubble destruction (UTMD) is a novel means of tissue-specific gene delivery. This approach systemically infuses transgenes precoupled to gas-filled lipid microbubbles that are burst within the microvasculature of target tissues via an ultrasound signal resulting in release of DNA and transfection of neighboring cells within the tissue. Previous work has shown that adenovirus containing cDNA of UCP-1, injected into the epididymal fat pads in mice, induced localized fat depletion, improving glucose tolerance, and decreasing food intake in obese diabetic mice. Our group recently demonstrated that gene therapy by UTMD achieved beta cell regeneration in streptozotocin (STZ)-treated mice and baboons. We hypothesized that gene therapy with BMP7/PRDM16/PPARGC1A in skeletal muscle (SKM) of obese Zucker diabetic fatty (fa/fa) rats using UTMD technology would produce a brown adipose tissue (BAT) phenotype with UCP-1 overexpression. This study was designed as a proof of concept (POC) project. Obese Zucker rats were administered plasmid cDNA contructs encoding a gene cocktail with BMP7/PRDM16/PPARGC1A incorporated within microbubbles and intravenously delivered into their left thigh. Controls received UTMD with plasmids driving a DsRed reporter gene. An ultrasound transducer was directed to the thigh to disrupt the microbubbles within the microcirculation. Blood samples were drawn at baseline, and after treatment to measure glucose, insulin, and free fatty acids levels. SKM was harvested for immunohistochemistry (IHC). Our IHC results showed a reliable pattern of effective UTMD-based gene delivery in enhancing SKM overexpression of the UCP-1 gene. This clearly indicates that our plasmid DNA construct encoding the gene combination of PRDM16, PPARGC1A, and BMP7 reprogrammed adult SKM tissue into brown adipose cells in vivo. Our pilot established POC showing that the administration of the gene cocktail to SKM in this rat model of genetic obesity using UTMD gene therapy, engineered a BAT phenotype with UCP-1 over-expression. © 2017 IUBMB Life, 69(9):745-755, 2017.


Assuntos
Reprogramação Celular/genética , Diabetes Mellitus Experimental/terapia , Técnicas de Transferência de Genes , Terapia Genética , Obesidade/terapia , Tecido Adiposo Marrom/metabolismo , Animais , Proteína Morfogenética Óssea 7/genética , Diferenciação Celular/genética , Diabetes Mellitus Experimental/genética , Modelos Animais de Doenças , Humanos , Microbolhas/uso terapêutico , Músculo Esquelético/metabolismo , Músculo Esquelético/transplante , Obesidade/genética , Obesidade/fisiopatologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Plasmídeos/genética , Plasmídeos/uso terapêutico , Ratos , Ratos Zucker , Fatores de Transcrição/genética
15.
Front Neurosci ; 11: 49, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28261040

RESUMO

Changes in cerebral blood flow (CBF) during a hyperglycemic challenge were mapped, using perfusion-weighted MRI, in a group of non-human primates. Seven female baboons were fasted for 16 h prior to 1-h imaging experiment, performed under general anesthesia, that consisted of a 20-min baseline, followed by a bolus infusion of glucose (500 mg/kg). CBF maps were collected every 7 s and blood glucose and insulin levels were sampled at regular intervals. Blood glucose levels rose from 51.3 ± 10.9 to 203.9 ± 38.9 mg/dL and declined to 133.4 ± 22.0 mg/dL, at the end of the experiment. Regional CBF changes consisted of four clusters: cerebral cortex, thalamus, hypothalamus, and mesencephalon. Increases in the hypothalamic blood flow occurred concurrently with the regulatory response to systemic glucose change, whereas CBF declined for other clusters. The return to baseline of hypothalamic blood flow was observed while CBF was still increasing in other brain regions. The spatial pattern of extra-hypothalamic CBF changes was correlated with the patterns of several cerebral networks including the default mode network. These findings suggest that hypothalamic blood flow response to systemic glucose levels can potentially be explained by regulatory activity. The response of extra-hypothalamic clusters followed a different time course and its spatial pattern resembled that of the default-mode network.

16.
Brain Circ ; 2(3): 141-145, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30276291

RESUMO

Nonhuman primates (NHPs) are alike humans in size, behavior, physiology, biochemistry, and immunology. Given close similarities to humans, the NHP model offers exceptional opportunities to understand the biological mechanisms and translational applications with direct relevance to human conditions. Here, we evaluate the opportunities and limitations of NHPs as animal models for translational regenerative medicine. NHP models of human disease propose exceptional opportunities to advance stem cell-based therapy by addressing pertinent translational concerns related to this research. Nonetheless, the value of these primates must be carefully assessed, taking into account the expense of specialized equipment and requirement of highly specialized staff. Well-designed initial fundamental studies in small animal models are essential before translating research into NHP models and eventually into human trials. In addition, we suggest that applying a directed and collaborative approach, as seen in the evolution of stroke NHP models, will greatly benefit the translation of stem cell therapy in other NHP disease models.

17.
Gac Med Mex ; 151(6): 731-40, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-26581531

RESUMO

INTRODUCTION: There are few studies integrating the common causes of osteoporosis and obesity (disorders of body composition). A first step is to investigate correlations between their biological phenotypes to determine their common integrative physiology. OBJECTIVE: To correlate the variation of bone mineral density with phenotypes of body composition and biomarkers of bone physiology, insulin-glucose axis, and adipose tissue. METHODS: Cross-sectional study of 75 women (aged 18-45 years). MEASUREMENTS: Body mass index, waist, fat mass, lean mass (dual-energy X-ray absorptiometry), glucose, insulin, osteocalcin, leptin, tumor necrosis factor alpha. STATISTICAL ANALYSIS: multivariate general linear model, SPSS v.22, p<0.05. RESULTS: Age: 32.08±7.33. Bone mineral content multivariate general linear model 1 with two phenotypes excluded (glucose, insulin): osteocalcin (ß=-0.228, p=0.011), lean mass (ß=0.606, p=0.001) and fat mass (ß=1.237, p=0.001) in 62.0%. The bone mineral density multivariate general linear model 2 with three phenotypes excluded (body mass index, glucose, tumor necrosis factor alpha): insulin (ß=0.250, p=0.024), osteocalcin (ß=-0.362, p=0.001), lean mass (ß=0.512, p=0.001) and fat mass (ß=0.701, p=0.001) in 46.3%. CONCLUSIONS: Results show that body composition with an increased lean mass is beneficial to bone. This study reaffirms the importance of performing regular exercise to prevent muscle loss.


Assuntos
Tecido Adiposo/fisiologia , Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Absorciometria de Fóton/métodos , Adolescente , Adulto , Biomarcadores/metabolismo , Índice de Massa Corporal , Estudos Transversais , Feminino , Glucose/metabolismo , Humanos , Insulina/metabolismo , Modelos Lineares , Pessoa de Meia-Idade , Adulto Jovem
18.
J Med Primatol ; 44(4): 202-17, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26122701

RESUMO

BACKGROUND: Non-human primate (NHP) diabetic models using chemical ablation of ß-cells with STZ have been achieved by several research groups. Chemotherapeutic STZ could lead to serious adverse events including nephrotoxicity, hepatotoxicity, and mortality. METHODS: We implemented a comprehensive therapeutic strategy that included the tether system, permanent indwelling catheter implants, an aggressive hydration protocol, management for pain with IV nubain and anxiety with IV midazolam, moment-by-moment monitoring of glucose levels post-STZ administration, and continuous intravenous insulin therapy. RESULTS: A triphasic response in blood glucose after STZ administration was fully characterized. A dangerous hypoglycemic phase was also detected in all baboons. Other significant findings were hyperglycemia associated with low levels of plasma leptin, insulin and C-peptide concentrations, hyperglucagonemia, and elevated non-esterified fatty acids (NEFA) concentrations. CONCLUSIONS: We successfully induced frank diabetes by IV administering a single dose of pharmaceutical-grade STZ safely and without adverse events in conscious tethered baboons.


Assuntos
Diabetes Mellitus Experimental/etiologia , Modelos Animais de Doenças , Papio hamadryas/metabolismo , Administração Intravenosa , Animais , Glicemia/análise , Cateteres de Demora , Hiperglicemia/induzido quimicamente , Masculino , Estreptozocina/administração & dosagem , Estreptozocina/farmacologia
19.
Front Genet ; 5: 380, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25477898

RESUMO

The prevalence of type 2 diabetes (T2D) is rising rapidly and in Mexicans is ~19%. T2D is affected by both environmental and genetic factors. Although specific genes have been implicated in T2D risk few of these findings are confirmed in studies of Mexican subjects. Our aim was to replicate associations of 39 single nucleotide polymorphisms (SNPs) from 10 genes with T2D-related phenotypes in a community-based Mexican cohort. Unrelated individuals (n = 259) living in southeastern Mexico were enrolled in the study based at the University of Yucatan School of Medicine in Merida. Phenotypes measured included anthropometric measurements, circulating levels of adipose tissue endocrine factors (leptin, adiponectin, pro-inflammatory cytokines), and insulin, glucose, and blood pressure. Association analyses were conducted by measured genotype analysis implemented in SOLAR, adapted for unrelated individuals. SNP Minor allele frequencies ranged from 2.2 to 48.6%. Nominal associations were found for CNR1, SLC30A8, GCK, and PCSK1 SNPs with systolic blood pressure, insulin and glucose, and for CNR1, SLC30A8, KCNJ11, and PCSK1 SNPs with adiponectin and leptin (p < 0.05). P-values greater than 0.0014 were considered significant. Association of SNPs rs10485170 of CNR1 and rs5215 of KCNJ11 with adiponectin and leptin, respectively, reached near significance (p = 0.002). Significant association (p = 0.001) was observed between plasma leptin and rs5219 of KCNJ11.

20.
Artigo em Inglês | MEDLINE | ID: mdl-25429366

RESUMO

BACKGROUND: Blood glucose levels regulate the rate of insulin secretion, which is the body's mechanism for preventing excessive elevation in blood glucose. Impaired glucose metabolism and insulin resistance have been linked to excess body fat composition. Here, we quantify abdominal muscle and abdominal adipose tissue compartments in a large nonhuman primate, the baboon, and investigate their relationship with serum glucose response to a hyperglycemic challenge. METHODS: Five female baboons were fasted for 16 hours prior to 90 minute body imaging experiment that consisted of a 20-min baseline, followed by a bolus infusion of glucose (500mg/kg). The blood glucose was sampled at regular intervals. The total volumes of the muscle, visceral and subcutaneous adipose tissue were measured. RESULTS AND DISCUSSION: We found that adipose tissue composition predicted fluctuations in glucose responses to a hyperglycemic challenge of a non-human primate. Animals with higher visceral adiposity showed significantly reduced glucose elimination. The glucose responses were positively correlated with body weight, visceral and muscle fat (p < 0.005). Polynomial regression analysis showed that body weight, visceral and muscle were significant. CONCLUSIONS: These results reveal the similarity between humans and baboons with respect to glucose metabolism and strengthen the utility of baboon for biomedical research.

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