Genome-wide association study and polygenic score assessment of insulin resistance.

Insulin resistance (IR) and beta cell dysfunction are the major drivers of type 2 diabetes (T2D). Genome-Wide Association Studies (GWAS) on IR have been predominantly conducted in European populations, while Middle Eastern populations remain largely underrepresented. We conducted a GWAS on the indices of IR (HOMA2-IR) and beta cell function (HOMA2-%B) in 6,217 non-diabetic individuals from the Qatar Biobank (QBB; Discovery cohort; n = 2170, Replication cohort; n = 4047) with and without body mass index (BMI) adjustment. We also developed polygenic scores (PGS) for HOMA2-IR and compared their performance with a previously derived PGS for HOMA-IR (PGS003470). We replicated 11 loci that have been previously associated with HOMA-IR and 24 loci that have been associated with HOMA-%B, at nominal statistical significance. We also identified a novel locus associated with beta cell function near VEGFC gene, tagged by rs61552983 (P = 4.38 × 10-8). Moreover, our best performing PGS (Q-PGS4; Adj R2 = 0.233 ± 0.014; P = 1.55 x 10-3) performed better than PGS003470 (Adj R2 = 0.194 ± 0.014; P = 5.45 x 10-2) in predicting HOMA2-IR in our dataset. This is the first GWAS on HOMA2 and the first GWAS conducted in the Middle East focusing on IR and beta cell function. Herein, we report a novel locus in VEGFC that is implicated in beta cell dysfunction. Inclusion of under-represented populations in GWAS has potentials to provide important insights into the genetic architecture of IR and beta cell function.

A hybrid construct of decellularized matrix and fibrin for differentiating adipose stem cells into insulin-producing cells, an optimized in vitro assessment.

The generation of insulin-producing cells (IPCs) is an attractive approach for replacing damaged ß cells in diabetic patients. In the present work, we introduced a hybrid platform of decellularized amniotic membrane (dAM) and fibrin encapsulation for differentiating adipose tissue-derived stem cells (ASCs) into IPCs. ASCs were isolated from healthy donors and characterized. Human AM was decellularized, and its morphology, DNA, collagen, glycosaminoglycan (GAG) contents, and biocompatibility were evaluated. ASCs were subjected to four IPC differentiation methods, and the most efficient method was selected for the experiment. ASCs were seeded onto dAM, alone or encapsulated in fibrin gel with various thrombin concentrations, and differentiated into IPCs according to a method applying serum-free media containing 2-mercaptoethanol, nicotinamide, and exendin-4. PDX-1, GLUT-2 and insulin expression were evaluated in differentiated cells using real-time PCR. Structural integrity and collagen and GAG contents of AM were preserved after decellularization, while DNA content was minimized. Cultivating ASCs on dAM augmented their attachment, proliferation, and viability and enhanced the expression of PDX-1, GLUT-2, and insulin in differentiated cells. Encapsulating ASCs in fibrin gel containing 2 mg/ml fibrinogen and 10 units/ml thrombin increased their differentiation into IPCs. dAM and fibrin gel synergistically enhanced the differentiation of ASCs into IPCs, which could be considered an appropriate strategy for replacing damaged ß cells.

DNA Methylation-Based Assessment of Cell Composition in Human Pancreas and Islets.

Assessment of pancreas cell type composition is crucial to the understanding of the genesis of diabetes. Current approaches use immunodetection of protein markers, for example, insulin as a marker of ß-cells. A major limitation of these methods is that protein content varies in physiological and pathological conditions, complicating the extrapolation to actual cell number. Here, we demonstrate the use of cell type-specific DNA methylation markers for determining the fraction of specific cell types in human islet and pancreas specimens. We identified genomic loci that are uniquely demethylated in specific pancreatic cell types and applied targeted PCR to assess the methylation status of these loci in tissue samples, enabling inference of cell type composition. In islet preparations, normalization of insulin secretion to ß-cell DNA revealed similar ß-cell function in pre-type 1 diabetes (T1D), T1D, and type 2 diabetes (T2D), which was significantly lower than in donors without diabetes. In histological pancreas specimens from recent-onset T1D, this assay showed ß-cell fraction within the normal range, suggesting a significant contribution of ß-cell dysfunction. In T2D pancreata, we observed increased α-cell fraction and normal ß-cell fraction. Methylation-based analysis provides an accurate molecular alternative to immune detection of cell types in the human pancreas, with utility in the interpretation of insulin secretion assays and the assessment of pancreas cell composition in health and disease.

The differences in homeostasis model assessment values in type 2 diabetic patients with different lengths of history of diabetes

ABSTRACT Objective Type 2 diabetes (T2DM) is characterized by the progressive deterioration of pancreatic islet β-cell function over time and insulin resistance. Knowing more about the differences in pancreatic islet function in T2DM patients who have had diabetes for different lengths of time can help improve therapy for T2DM. Subjects and methods We conducted a cross-sectional study to compare islet β-cell function and insulin resistance in T2DM patients (n = 3,254) who had had diabetes for different lengths of time and those in normal controls (n = 794) using ANOVA and LSD analysis. Results We found that compared with that in normal controls, HOMA-β in T2DM patients with a history of diabetes of less than 1 year was lower (approximately 52% of that of normal controls, p = 0.003), while HOMA-IR in these patients was higher (approximately 50% of that of normal controls, p = 0.007). Compared with that in other diabetic patients, HOMA-β in patients with a history of diabetes of more than 30 years was the lowest. HOMA-IR in patients with a history of diabetes of between 20 and 30 years was lower than that in other diabetic patients (p < 0.05). Conclusions There were obvious decreases in HOMA-β and increases in HOMA-IR in T2DM patients with a history of diabetes of less than 1 year compared with those in normal controls. Therefore, early screening and intervention for T2DM might help improve islet function and delay the progression of diabetes.

Indução de endividamento hospitalar na compra de medicamento em situação de monopólio: o caso do mesilato de imatinibe / Induction of hospital indebtedness due to medicine purchases under monopoly conditions: the case of imatinib mesylate / Inducción de la deuda hospitalaria en la compra de medicamentos en monopolio: el caso de mesilato de imatinib

Os gastos com medicamentos correspondem a uma grande parcela do orçamento em saúde. Sendo assim, a produção de conhecimento sobre o uso desses recursos é essencial na tomada de decisão em saúde pública e melhoria da assistência farmacêutica. Este estudo teve como objetivo analisar o processo de endividamento em um hospital universitário de alta complexidade devido ao gasto crescente com a aquisição de mesilato de imatinibe. Por meio de análise documental e registros no Sistema de Informações Hospitalares (SIH) entre 2002 e 2010, realizou-se um estudo descritivo. A partir do caminho da incorporação do medicamento, foram mapeadas as estratégias da indústria farmacêutica e do governo, assim como as respostas governamentais de redução do preço. A sistematização e publicação de informações guardadas em arquivos e na memória podem contribuir para o acompanhamento dos resultados dos programas mantidos pelo Ministério da Saúde.

Medicine expenditures consume a large share of the health budget, so knowledge on the use of these funds is essential for decision-making in public health and improvement of pharmaceutical care. This study analyzed the indebtedness of a high-complexity university hospital due to increased spending on imatinib mesylate. The descriptive study was based on analysis of documents and records in the Hospital Information System (SIH) from 2002 to 2010. Starting with inclusion of the medicine in the budget, the study mapped strategies by the pharmaceutical industry and government, as well as government responses to reduce the product's price. The systematization and publication of information stored in files and electronic databases can help monitor the results of programs funded by the Brazilian Ministry of Health.

Los gastos en medicamentos representan una gran proporción del presupuesto de salud, por lo que la producción de conocimiento sobre el uso de estos recursos es esencial en la toma de decisiones en salud pública y la mejora de la atención farmacéutica. Este estudio tuvo como objetivo analizar el proceso de endeudamiento en un hospital universitario de alta complejidad, debido al aumento de los gastos en la adquisición de mesilato de imatinib. A través del análisis de los documentos y registros en el Sistema de Información Hospitalaria (SIH) entre 2002 y 2010, se realizó un estudio descriptivo. A partir de la incorporación del medicamento, se mapearon las estrategias de la industria farmacéutica y del gobierno, así como las respuestas del gobierno para reducir el precio. La sistematización y publicación de la información almacenada en los archivos y su memoria puede contribuir para el seguimiento de los resultados de los programas mantenidos por el Ministerio de Salud.

Distribución de las concentraciones de glucosa e indulina basal, HOMA IR Y MOMA ßcell en niños y adolescentes de la ciudad de Maracaibo, Venezuela / Distribution of fasting glucose, insulin, homeostasis model assessment (HOMA) insulin resistance (IR) and HOMA ß cell in children and adolescents from Maracaibo, Venezuela

Background: The raising prevalence of obesity among children increases the risk of insulin resistance and its adverse metabolic consequences. Aim: To determine the distributions of fasting serum glucose, insulin, HOMA IR and HOMA ß cell in a representative sample of children and adolescents from Maracaibo-Venezuela. Subjects and Methods: Fasting insulin and glucose were measured in 418 children and adolescents (191 boys and 227 girls) of 7, 9, 11, 13, 15 years of age. HOMA IR and HOMA ß cell were calculated. Results: Insulin levels were lower in 7 and 9 year-old girls and 7 year-old boys compared with 11, 13 and 15 year-old girls and boys. Fasting glucose concentrations were similar in boys and girls. HOMA IR was lower in 7 year-old girls compared to 11, 13 and 15 years-old girls, whereas boys in every age showed similar values. HOMA ß cell was higher in 11 and 13 year-old girls. Conclusions: Our findings provide useful values to assess insulin resistance and ß-cell functioning in children and adolescents.