Ethnic differences in the relationship between ectopic fat deposition and insulin sensitivity in Black African and White European men across a spectrum of glucose tolerance

Aim: To examine the hypothesis that there would be ethnic differences in the relationship between ectopic fat and tissue-specific insulin resistance (IR) across a spectrum of glucose tolerance in Black African (BA) and White European (WE) men. Materials and Methods: Fifty-three WE men (23/10/20 normal glucose tolerance [NGT]/impaired glucose tolerance [IGT]/type 2 diabetes [T2D]) and 48 BA men (20/10/18, respectively) underwent a two-step hyperinsulinaemic-euglycaemic clamp with infusion of D-[6,6-2H2]-glucose and [2H5]-glycerol to assess hepatic, peripheral and adipose tissue IR. Magnetic resonance imaging was used to measure subcutaneous adipose tissue, visceral adipose tissue (VAT) and intrahepatic lipid (IHL). Associations between ectopic fat and IR were assessed using linear regression models. Results: There were no differences in tissue-specific IR between ethnic groups at any stage of glucose tolerance. VAT level was consistently lower in the BA population; NGT (p = 0.013), IGT (p = 0.006) and T2D (p = 0.015). IHL was also lower in the BA compared with the WE men (p = 0.013). VAT and IHL levels were significantly associated with hepatic IR in the BA population (p = 0.001) and with peripheral IR in the WE population (p = 0.027). Conclusions: The present study suggests that BA and WE men exhibit the same degree of IR across a glucose tolerance continuum, but with lower VAT and IHL levels in the BA population, suggesting that IR may be driven by a mechanism other than increased ectopic fat accumulation in BA men.</p

Open Data Portals in Africa: An Analysis of Open Government Data Initiatives

African countries like other developed nations are beginning to open up data towards attaining transparency and accountability. A better understanding by citizens of what a government does and the level of performance achieved can be better understood by making public sector data open. Citizens can therefore hold their government accountable for not meeting up with stated goals and misconducts. This study employs a survey through content analysis to evaluate the extent of implementation of open data portals. Variables used for the evaluation are Berners Lee 5 star of open data, implementation technology, data formats, licensing, major data sets and functionality across the African continent. A total of twenty two data portals from seventeen different countries were assessed. Seven of the data portals representing 32% of the total number of the data portals were implemented using Drupal tool (Dkan). About 60% of the portals under investigation are national initiatives, and Nigeria has the only regional/state initiative and the only two independent organisation data portals. The only two university related-initiatives as well as the only city-based data portal were from South Africa, while a specialised data portal dedicated to the Ebola crisis was captured from Sierra Leone. The dates for the creation of the data portals span from 2011 to the current year (2015). The result indicates that an appreciable effort is being made in the creation of data portals; however, more countries need to take the giant stride to data provisioning in the open formats. More data sets also need to be populated onto the portals. Movement towards attaining the 5- star status of open data portals is in progress but a lot needs to be done towards attaining this. There is also a need to complement the efforts of national governments, and this could be done by regional/state, cities, universities, and independent organisations.Keywords: Data Portal, Open Data, Visual Data, Data Formats, 5 Star of Open Dat

Insulin sensitivity indices in Black Africans and White Europeans with Type 2 diabetes:a comparison of fasting, meal tolerance test and Hyperinsulinemic-euglycemic clamp indices

Conference poste

Ethnic differences in beta cell function occur independently of insulin sensitivity and pancreatic fat in black and white men

Introduction It is increasingly recognized that type 2 diabetes (T2D) is a heterogenous disease with ethnic variations. Differences in insulin secretion, insulin resistance and ectopic fat are thought to contribute to these variations. Therefore, we aimed to compare postprandial insulin secretion and the relationships between insulin secretion, insulin sensitivity and pancreatic fat in men of black West African (BA) and white European (WE) ancestry.Research design and methods A cross-sectional, observational study in which 23 WE and 23 BA men with normal glucose tolerance, matched for body mass index, underwent a mixed meal tolerance test with C peptide modeling to measure beta cell insulin secretion, an MRI to quantify intrapancreatic lipid (IPL), and a hyperinsulinemic-euglycemic clamp to measure whole-body insulin sensitivity.Results Postprandial insulin secretion was lower in BA versus WE men following adjustment for insulin sensitivity (estimated marginal means, BA vs WE: 40.5 (95% CI 31.8 to 49.2) × 103 vs 56.4 (95% CI 48.9 to 63.8) × 103 pmol/m2 body surface area × 180 min, p=0.008). There was a significantly different relationship by ethnicity between IPL and insulin secretion, with a stronger relationship in WE than in BA (r=0.59 vs r=0.39, interaction p=0.036); however, IPL was not a predictor of insulin secretion in either ethnic group following adjustment for insulin sensitivity.Conclusions Ethnicity is an independent determinant of beta cell function in black and white men. In response to a meal, healthy BA men exhibit lower insulin secretion compared with their WE counterparts for their given insulin sensitivity. Ethnic differences in beta cell function may contribute to the greater risk of T2D in populations of African ancestry

The Link between Obesity and Inflammatory Markers in the Development of Type 2 Diabetes in Men of Black African and White European Ethnicity

In this study, we aimed to assess ethnic differences in visceral (VAT), deep subcutaneous (dSAT), and superficial subcutaneous (sSAT) adipose tissue and their relationships with inflammatory markers between white European (WE) and black West African (BWA) men with normal glucose tolerance (NGT) and type 2 diabetes (T2D). Forty-two WE (23 NGT/19 T2D) and 43 BWA (23 NGT/20 T2D) men underwent assessment of plasma inflammatory markers using immunoassays alongside Dixon magnetic resonance imaging to quantify L4-5 VAT, dSAT and sSAT. Despite no ethnic differences in sSAT and dSAT, BWA men exhibited lower VAT (p = 0.002) and dSAT:sSAT (p = 0.047) than WE men. Adiponectin was inversely associated with sSAT in WE (p = 0.041) but positively associated in BWA (p = 0.031) men with T2D. Interleukin-6 (IL-6) was associated with VAT in WE but not in BWA men with NGT (WE: p = 0.009, BWA: p = 0.137) and T2D (WE: p = 0.070, BWA: p = 0.175). IL-6 was associated with dSAT in only WE men with NGT (WE: p = 0.030, BWA: p = 0.833). The only significant ethnicity interaction present was for the relationship between adiponectin and sSAT (Pinteraction = 0.003). The favourable adipose tissue distribution and the weaker relationships between adiposity and inflammation in BWA men suggest that adipose tissue inflammation may play a lesser role in T2D in BWA than WE men

Ethnic differences in the relationship between ectopic fat deposition and insulin sensitivity in Black African and White European men across a spectrum of glucose tolerance

No description supplie