scholarly journals Fasting insulin sensitivity indices are not better than routine clinical variables at predicting insulin sensitivity among Black Africans: a clamp study in sub-Saharan Africans

2014 ◽  
Vol 14 (1) ◽  
Author(s):  
Eugene Sobngwi ◽  
Andre-Pascal Kengne ◽  
Justin B Echouffo-Tcheugui ◽  
Simeon Choukem ◽  
Joelle Sobngwi-Tambekou ◽  
...  
Keyword(s):  
Insulin Sensitivity ◽  
Fasting Insulin ◽  
Black Africans ◽  
Clinical Variables ◽  
Sensitivity Indices ◽  
Sub Saharan ◽  
Clamp Study ◽  
Better Than

scholarly journals Surrogate Measures of Insulin Resistance in Middle-aged Non-diabetic Subjects

2013 ◽  
Vol 59 (6) ◽  
pp. 279-284
Author(s):  
Csép Katalin
Keyword(s):  
Insulin Resistance ◽  
Metabolic Syndrome ◽  
Insulin Sensitivity ◽  
Fasting Insulin ◽  
Middle Aged ◽  
Insulin Levels ◽  
The Metabolic Syndrome ◽  
Sensitivity Indices ◽  
Increased Risk ◽  
Surrogate Measures

Abstract Objective: Insulin resistance has been shown to be a risk factor for type 2 diabetes and cardiovascular disease. The assessment of insulin sensitivity in the clinical practice, however, faces several difficulties. The study proposes to analyze surrogate measures of insulin resistance based on fasting insulin levels in central Romania, and check whether the diagnosis of the metabolic syndrome is an adequate strategy to identify middle-aged persons with reduced insulin sensitivity. Methods: Anthropometric measurements, metabolic profile, and surrogates measures of insulin sensitivity (GIR, HOMA, QUICKI, FIRI, Belfiore, Bennett, Raynaud, McAuley index) based on fasting insulin levels were assessed in 233 non-diabetic middle aged subjects. Results: Cutoff values, determined as the lowest quartile of insulin sensitivity for fasting insulin, HOMA, IRI (1/QUICKI), FIRI and Belfiore's, Bennett's, Raynaud's and McAuley's insulin sensitivity indices were 10.49 mU/L, 2.1, 3.01, 2.32, and 0.03, 1.34, 3.81, 6.29, 5.82. Components of the metabolic syndrome showed moderate but significant correlations with the surrogate measures of insulin resistance (r = 0.22-0.56, p <0.05). HOMA-IR and McAuley indices were the best predictors of clustered cardiometabolic risk factors (AUC - 0.83, 0.81 and 0.82). The metabolic syndrome diagnosis performed well in identifying patients with reduced insulin sensitivity (McAuley 2: sensitivity - 0.78, specificity - 0.84). Conclusion: Fasting insulin derived insulin sensitivity indices may help the recognittion of insulin resistant states predicting cardiometabolic disorders. Actively looking for insulin resistance by these simple indices, or by diagnosing the metabolic syndrome, those at increased risk can be recognized

scholarly journals The Relationship between Adiposity and Insulin Sensitivity in African Women Living with the Polycystic Ovarian Syndrome: A Clamp Study

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Emmanuella Doh ◽  
Armand Mbanya ◽  
Jean Dupont Kemfang-Ngowa ◽  
Sama Dohbit ◽  
Mycilline Tchana-Sinou ◽  
...  
Keyword(s):  
Insulin Sensitivity ◽  
Energy Expenditure ◽  
Resting Energy Expenditure ◽  
African Women ◽  
Euglycemic Hyperinsulinemic Clamp ◽  
Total Body Mass ◽  
Sub Saharan ◽  
Total Body ◽  
Clamp Study ◽  
Resting Energy

Objectives. We aimed to assess the variation of insulin sensitivity in relation to obesity in women living with PCOS in a sub-Sahara African setting.Methods. We studied body composition, insulin sensitivity, and resting energy expenditure in 14 PCOS patients (6 obese and 8 nonobese) compared to 10 matched nonobese non-PCOS subjects. Insulin sensitivity was assessed using the gold standard 80 mU/m2/min euglycemic-hyperinsulinemic clamp and resting energy expenditure was measured by indirect calorimetry.Results. Insulin sensitivity adjusted to lean mass was lowest in obese PCOS subjects and highest in healthy subjects (11.2[10.1–12.4]versus 12.9[12.1–13.8]versus 16.6[13.8–17.9],p=0.012); there was a tendency for resting energy expenditure adjusted for total body mass to decrease across the groups highest in obese PCOS subjects (1411[1368–1613]versus 1274[1174–1355]versus 1239[1195–1454],p=0.306).Conclusion. In this sub-Saharan population, insulin resistance is associated with PCOS per se but is further aggravated by obesity. Obesity did not seem to be explained by low resting energy expenditure suggesting that dietary intake may be a determinant of the obesity in this context.

scholarly journals PWD/PhJ and WSB/EiJ Mice Are Resistant to Diet-Induced Obesity But Have Abnormal Insulin Secretion

Endocrinology ◽  
2011 ◽  
Vol 152 (8) ◽  
pp. 3005-3017 ◽  
Author(s):  
Katie T. Y. Lee ◽  
Subashini Karunakaran ◽  
Maggie M. Ho ◽  
Susanne M. Clee
Keyword(s):  
Insulin Secretion ◽  
Insulin Sensitivity ◽  
Large Scale ◽  
Mouse Strains ◽  
Second Phase ◽  
Fasting Insulin ◽  
High Fat ◽  
Diet Induced Obesity ◽  
Obesity And Diabetes

Recently, novel inbred mouse strains that are genetically distinct from the commonly used models have been developed from wild-caught mice. These wild-derived inbred strains have been included in many of the large-scale genomic projects, but their potential as models of altered obesity and diabetes susceptibility has not been assessed. We examined obesity and diabetes-related traits in response to high-fat feeding in two of these strains, PWD/PhJ (PWD) and WSB/EiJ (WSB), in comparison with C57BL/6J (B6). Young PWD mice displayed high fasting insulin levels, although they had normal insulin sensitivity. PWD mice subsequently developed a much milder and delayed-onset obesity compared with B6 mice but became as insulin resistant. PWD mice had a robust first-phase and increased second-phase glucose-stimulated insulin secretion in vivo, rendering them more glucose tolerant. WSB mice were remarkably resistant to diet-induced obesity and maintained very low fasting insulin throughout the study. WSB mice exhibited more rapid glucose clearance in response to an insulin challenge compared with B6 mice, consistent with their low percent body fat. Interestingly, in the absence of a measurable in vivo insulin secretion, glucose tolerance of WSB mice was better than B6 mice, likely due to their enhanced insulin sensitivity. Thus PWD and WSB are two obesity-resistant strains with unique insulin secretion phenotypes. PWD mice are an interesting model that dissociates hyperinsulinemia from obesity and insulin resistance, whereas WSB mice are a model of extraordinary resistance to a high-fat diet.

scholarly journals Chronic kidney disease and obesity bias surrogate estimates of insulin sensitivity compared with the hyperinsulinemic euglycemic clamp

2017 ◽  
Vol 312 (3) ◽  
pp. E175-E182 ◽  
Author(s):  
Iram Ahmad ◽  
Leila R. Zelnick ◽  
Nicole R. Robinson ◽  
Adriana M. Hung ◽  
Bryan Kestenbaum ◽  
...  
Keyword(s):  
Chronic Kidney Disease ◽  
Insulin Sensitivity ◽  
Kidney Disease ◽  
Oral Glucose ◽  
Cross Sectional ◽  
Euglycemic Clamp ◽  
Insulin Kinetics ◽  
Hyperinsulinemic Euglycemic Clamp ◽  
Sensitivity Indices ◽  
Organ Specific

Insulin sensitivity can be measured by procedures such as the hyperinsulinemic euglycemic clamp or by using surrogate indices. Chronic kidney disease (CKD) and obesity may differentially affect these measurements because of changes in insulin kinetics and organ-specific effects on insulin sensitivity. In a cross-sectional study of 59 subjects with nondiabetic CKD [estimated glomerular filtration rate: (GFR) <60 ml·min−1·1.73 m2] and 39 matched healthy controls, we quantified insulin sensitivity by clamp (SIclamp), oral glucose tolerance test, and fasting glucose and insulin. We compared surrogate insulin sensitivity indices to SIclamp using descriptive statistics, graphical analyses, correlation coefficients, and linear regression. Mean age was 62.6 yr; 48% of the participants were female, and 77% were Caucasian. Insulin sensitivity indices were 8–38% lower in participants with vs. without CKD and 13–59% lower in obese compared with nonobese participants. Correlations of surrogate indices with SIclamp did not differ significantly by CKD or obesity status. Adjusting for SIclamp in addition to demographic factors, Matsuda index was 15% lower in participants with vs. without CKD ( P = 0.09) and 36% lower in participants with vs. without obesity ( P = 0.0001), whereas 1/HOMA-IR was 23% lower in participants with vs. without CKD ( P = 0.02) and 46% lower in participants with vs. without obesity ( P < 0.0001). We conclude that CKD and obesity do not significantly alter correlations of surrogate insulin sensitivity indices with SIclamp, but they do bias surrogate measurements of insulin sensitivity toward lower values. This bias may be due to differences in insulin kinetics or organ-specific responses to insulin.

scholarly journals Impact of high energy oral nutritional supplements consumed in the late afternoon on appetite, energy intake and cardio-metabolic risk factors in females with lower BMI

2021 ◽  
Author(s):  
Sadia Fatima ◽  
Konstantinos Gerasimidis ◽  
Charlotte Wright ◽  
Dalia Malkova
Keyword(s):  
Insulin Sensitivity ◽  
Energy Expenditure ◽  
Energy Intake ◽  
Nutritional Supplement ◽  
High Energy ◽  
Fasting Insulin ◽  
Daily Energy Intake ◽  
Late Afternoon ◽  
Oral Nutritional Supplements ◽  
Daily Energy

Abstract Background/Objective Morning consumption of a single dose of high-energy oral nutritional supplement (ONS) in females with a lower BMI displaces some of the food eaten at breakfast but increases overall daily energy intake. This study investigated the effectiveness of ONS intake in the late afternoon and for longer duration. Subjects/Methods Twenty-one healthy females (mean ± SD, age 25 ± 5 years; BMI 18.7 ± 1.2 kg/m2) participated in a randomised, crossover study with two experimental trials. In the afternoon of days 1–5, participants consumed either ONS (2.510 MJ) or low-energy PLACEBO drink (0.377 MJ) and recorded food eaten at home. On day six, energy intake was measured during buffet meals, and energy expenditure, appetite measurements and blood samples were collected throughout the day. Result Over the 5-day period, in the ONS trial energy intake from evening meals was lower (ONS, 2.7 ± 0.25 MJ; Placebo, 3.6 ± 0.25 MJ, P = 0.01) but averaged total daily energy intake was higher (ONS, 9.2 ± 0.3 MJ; PLACEBO, 8.2 ± 0.4 MJ, P = 0.03). On day six, energy intake, appetite scores, plasma GLP-1 and PYY, and energy expenditure were not significantly different between the two trials but fasting insulin concentration and HOMAIR, were higher (P < 0.05) and insulin sensitivity score based on fasting insulin and TAG lower (P < 0.05) in ONS trial. Conclusion Late afternoon consumption of ONS for five consecutive days by females with a lower BMI has only a partial and short-lived energy intake suppression and thus increases daily energy intake but reduces insulin sensitivity.

Abstract 089: CD36 Genetic Variant Impacts Nitric Oxide Regulation of Endothelial Function: Response to Chronic Treatment with Phosphodiesterase 5 Inhibition

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Cyndya A Shibao ◽  
Jorge E Celedonio ◽  
Latisha Gregory-Love ◽  
Claudia E Ramirez ◽  
Amy C Arnold ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Insulin Sensitivity ◽  
Endothelial Function ◽  
Chronic Treatment ◽  
Genetic Variant ◽  
Sildenafil Citrate ◽  
Flow Mediated Dilation ◽  
Fasting Insulin ◽  
The Mean ◽  
Phosphodiesterase 5

CD36, a scavenger receptor expressed on endothelial cells, interacts with thrombospodin-1, a matrix protein that modulates nitric oxide-soluble guanylate cyclase (NO-sGC) signaling. CD36 genetic variants associate with endothelial dysfunction, atherosclerosis, hypertension and insulin resistance. A coding variant of CD36 (rs3211938, G/T genotype) that causes partial CD36 deficiency (50% reduction) is common (~18%) in African Americans (AA); however, it is unknown, if this genotype influences NO-dependent endothelial function. This study examined whether potentiating NO-sGC pathways with the phosphodiesterase 5 inhibitor, sildenafil citrate, improves endothelial function and insulin sensitivity in AA women with or without the G/T genotype. Forty-six AA women with metabolic syndrome (MetS) participated in a 4-week, parallel-arm, double-blind, and placebo-controlled study. Carefully matched subjects were randomly assigned to sildenafil citrate 20 mg TID versus placebo; sildenafil (n= 23, 42±10 years old, BMI 39±5 kg/m2, fasting insulin 15±8 uU/ml) and placebo (n=23, age 43±10, BMI 39±6 kg/m2, fasting insulin 14±10 uU/ml). Primary endpoints were insulin sensitivity and endothelial function measured by intravenous glucose tolerance test and flow mediated dilation, respectively. Treatment compliance was documented with plasma sildenafil levels (mean 57±50 ng/ml). There was no difference in insulin sensitivity (p=0.676) or flow-mediated dilation (p=0.649) between intervention groups. However, subgroup analyses showed a significant interaction between sildenafil citrate treatment and G/T genotype (p=0.018). Sildenafil citrate improved endothelial function in G/T carriers (the mean difference: 2.9, the 95% CI: -0.90 to 6.8, p = 0.126) and decreased endothelial function in T/T carriers (the mean difference: -2.6, the 95% CI: -5.1 to -0.1, p = 0.040). We conclude that the rs3211938 common CD36 genetic variant influences NO-dependent endothelial function in response to chronic treatment with phosphodiesterase 5 inhibition. Further studies are needed to determine if rs3211938 and other common CD36 genotypes influence endothelial function and the inter-individual variability in response to the drug.

Abstract P149: The Effect of Alcohol Consumption on Insulin Sensitivity and Glycemic Status: A Systematic Review and Meta-analysis of Intervention Studies

Circulation ◽  
2014 ◽  
Vol 129 (suppl_1) ◽  
Author(s):  
Ilse C Schrieks ◽  
Annelijn L Heil ◽  
Henk F Hendriks ◽  
Kenneth J Mukamal ◽  
Joline W Beulens
Keyword(s):  
Systematic Review ◽  
Insulin Sensitivity ◽  
Alcohol Consumption ◽  
Intervention Studies ◽  
Meta Analysis ◽  
Moderate Alcohol Consumption ◽  
Fasting Insulin ◽  
Glycemic Status ◽  
Reduced Risk

Introduction: Moderate alcohol consumption is associated with a reduced risk of type 2 diabetes, but this relation appears stronger for women than men. The reduced risk of diabetes could be explained by improved insulin sensitivity or glycemic status, but results of intervention studies on this relation are inconsistent. Our aim was to conduct a systematic review and meta-analysis of intervention studies investigating the effect of alcohol consumption on insulin sensitivity and glycemic status. Design: Systematic review and meta-analysis of intervention studies. Data sources: PubMed and Embase were searched until May 2013 using a pre-specified search string. Methods: Intervention studies on the effect of more than 2 weeks alcohol consumption on biological markers of insulin sensitivity or glycemic status were identified and assessed on their quality. Pooled standardized mean differences (SMD) were calculated using either fixed or random effects models. Gender-stratified analyses and sensitivity analyses excluding studies with high doses of alcohol (> 40 g/day). In a meta-regression the influence of dosage and duration of intervention was tested. Results: We included 14 intervention studies in a meta-analysis on 6 glycemic endpoints. Alcohol consumption did not influence insulin sensitivity (SMD=0.06 [-0.13 to 0.26]) or fasting glucose (SMD=0.09 [-0.09 to 0.27]). Alcohol consumption reduced HbA1c (SMD=-0.62 [-1.01 to -0.23], P=0.002) and insulin concentrations (SMD=-0.17 [-0.34 to 0.00] P=0.049) compared with the control group. In women, alcohol consumption reduced fasting insulin (SMD=-0.23 [-0.41 to -0.04], P=0.019) and improved insulin sensitivity (SMD=0.19 [-0.03 to 0.41], P=0.087), but no significant differences were observed among men. Results were similar when only studies with moderate alcohol dosages were analysed and were not influenced by dosage and duration of the intervention. Conclusions: This study showed that moderate alcohol consumption may reduce fasting insulin and improve insulin sensitivity among women, but not among men. These effects may provide an explanation for the relation between alcohol consumption and type 2 diabetes. Furthermore, moderate alcohol consumption may reduce HbA1c levels among both men and women.

scholarly journals Contrasting Response Mechanisms of Maize Lines to Striga hermonthica

Agriculture ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 485
Author(s):  
Nnanna N. Unachukwu ◽  
Abebe Menkir ◽  
Adekemi Stanley ◽  
Ebenezer O. Farombi ◽  
Melaku Gedil
Keyword(s):  
Cost Effective ◽  
Resistance Mechanisms ◽  
Control Measures ◽  
Sub Saharan Africa ◽  
Striga Hermonthica ◽  
Maize Line ◽  
Parasitic Weed ◽  
Resistant Lines ◽  
Sub Saharan ◽  
Better Than

Strigahermonthica (Del.) Benth is a parasitic weed that devastates cereals in Sub-Saharan Africa. Several control measures have been proposed for the parasite, of these, host plant resistance is considered the most cost-effective for poor farmers. Some tolerant/resistant lines have been developed and these lines display tolerance/resistance mechanisms to the parasite. A series of studies was done to investigate some of the mechanisms through which a resistant (TZISTR1108) and a susceptible (5057) maize line responds to S. hermonthica infestation, as well as the effects of parasitism on these lines. In this study, TZISTR1108 stimulated the germination and attachment of fewer S. hermonthica plants than 5057, both in the laboratory and on the field. In TZISTR1108, the growth of the S. hermonthica plants, that successfully attached, was slowed. When compared to the un-infested plants, the infested resistant plants showed fewer effects of parasitism than the infested susceptible plants. The infested TZISTR1108 plants were more vigorous, taller and resembled their un-infected counterparts. There were substantial reductions in the stomatal conductance and nitrogen content of the 5057 upon infestation. The resistant inbred line showed multiple mechanisms of resistance to S. hermonthica infestation. It thrives better than the susceptible line by reducing the attachment of S. hermonthica and it delays the parasite’s development.

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