Network pharmacology-based elucidation of bioactive compounds and experimental exploration of antidiabetic mechanisms of Hydrolea zeylanica

This investigation systematically explored the underlying antidiabetic mechanism of Hydrolea zeylanica (HZH) by the approach of network pharmacology and experimental validation in restoring glucose homeostasis, and inflammation in high fat diet fed-streptozotocin (HFD/STZ)-induced type II diabetes (T2DM) rats. Network pharmacology analysis was conducted on 32 bioactive components of HZH. In silico ADME prediction, and physicochemical analysis of 32 compounds were used to assess their drug-likeness. Common targets between selected compounds, and T2DM were subjected for GO enrichment. Compound-target-pathway network was predicted with selected compounds and targets. HZH (300 and 400 mg/kg) were considered for GLUTs expression, and inflammation cytokines in T2DM rats. Network pharmacology showed the core relationship between 13 selected compounds, and 194 key target genes in insulin resistance, type II diabetes mellitus, insulin signaling pathways in T2DM. AKT1, AKT2, GSK3B, IL6, INSR, MAPK8, PPARA, GLUT1, GLUT2, GLUT4 were observed as the key targets in PPI network. HZH-400 significantly restored glucose homeostasis, and inflammatory markers in T2DM rats. It altered GLUT2, GLUT4 expression in liver, and skeletal muscle to normal. Bioactive compounds of HZH were found to control blood sugar level by modulating insulin resistance, type II diabetes mellitus, insulin signaling pathways, and glucose homeostasis, which in turn improved glucose uptake, insulin production in diabetes as shown in network pharmacology and glucose transporter expression studies.

Effect of Tinospora cordifolia on gestational diabetes mellitus and its complications

Ayurvedic system of medicine uses giloy or guduchi, also known as Tinospora cordifolia (TC), to treat diabetes and related diseases like hyperglycemia and hyperlipididemia. However, its usage in gestational diabetes mellitus (GDM) is not well studied. The primary objective of the study was to examine the effects of water extract of TC called satva, essential oil, and hydroalcoholic (HA) extract on GDM and its complications and to explore their mechanism of action using mice model. We used streptozotocin-induced diabetes in pregnant mice as murine model and tested TC preparations for anti-GDM activities. Blood glucose, insulin, litter size, and placental weight were assessed. ELISA method was used to measure plasma insulin level to compute homeostatic model assessment of insulin resistance (HOMA-IR), quantitative insulin sensitivity check index (QUICKI), and homeostatic model assessment for assessing beta cell function (HOMA-Beta) levels to estimate insulin resistance, insulin sensitivity, and beta cell function respectively. TC-treated groups had significantly higher serum insulin levels, QUICKI, average litter size, and lower placental weight (p < .001). TC oil and HA extract increased pancreatic beta cell activity according to the level of HOMA-Beta. TC lowered placenta weight and increased litter size significantly compared to control group. Our findings suggest that TC preparations preserve pancreatic beta cells, increase insulin production, decrease insulin resistance, and improve beta cell function, hence preventing GDM. TC preparations also reduced placental weight and increased litter size in mice. Based on these results, we recommend the clinical trial and testing of TC preparations for management of GDM and associated complications. Refer graphical abstract (Figure S1).

Impact of Two Types of Exercise Interventions on Leptin and Omentin Concentrations and Indicators of Lipid and Carbohydrate Metabolism in Males with Metabolic Syndrome

Leptin (LEP) and omentin (OMEN) are proteins whose concentrations change with the development of the metabolic syndrome (MetS). There are few intervention studies using various forms of physical activity in people with MetS that aim to determine the impact of physical exercise on the fluctuations of the presented hormones, and their results are contradictory. The present study aimed to examine the effect of two types of exercise intervention on LEP and OMEN concentrations and indicators of lipid and carbohydrate metabolism in males with MetS. The study included 62 males with MetS (age 36.6 ± 6.9 years, body mass 110.31 ± 17.37 kg), randomly allocated to EG1, the examined group with aerobic training (n = 21); EG2, the examined group with combined aerobic and resistance training (n = 21), both for 12 weeks, and the control group (CG) without interventions (n = 20). Anthropometric measurements, body composition (body fat [BF], android body fat [ANDR]), as well as a biochemical blood analysis (omentin [OMEN], leptin [LEP], quantitative insulin sensitivity check index [QUICKI], high-density lipoprotein cholesterol [HDL-C] and nonHDL-C) were performed at baseline, and at 6 and 12 weeks of interventions and after 4 weeks after ending intervention (follow-up). Intergroup and intragroup comparisons were performed. In the intervention groups EG1 and EG2, a decrease in BF was observed as well as an improvement in carbohydrate metabolism parameters. In the EG1 group, the level of ANDR was reduced. In EG2 a decrease in LEP concentration between measurements was confirmed. However, no significant changes were found in the concentration of OMEN in any groups. Combined aerobic and resistance exercises led to a higher reduction of LEP concentration than applying only aerobic training in males with MetS.

Pancreas fat content, insulin homeostasis and circulating endothelial microparticles in male essential hypertensive patients

The pancreas fat content has been poorly investigated in essential hypertension. The authors aim to relate pancreas and liver fat content with parameters measuring insulin resistance, beta-cell function and also with markers of endothelial dysfunction and platelet or endothelial cell destruction. The authors studied a group of 40 male hypertensive patients with well-controlled blood pressure, maintaining a stable weight, and having not changed their medication during the last year. Pancreas fat content was correlated with HOMA-IR (r = .616, p < .001), HOMA-S (r = -.439, p < .005), beta cell function parameter (r = .457, p < .005), and QUICKI (r = .412, p < .01), whereas liver fat was not patients in the highest quartile of pancreas fat content had more circulating endothelial microparticles than patients in the other quartiles (median 129 [94.3-200] vs. 60.9 [49.4-88.8], p = .002). However, patients in the highest quartile of the pancreas fat content distribution did not differ from the lowest in hyperemic response after ischemia nor circulating platelet microparticles count. Liver fat content was not related to any of the parameters studied. In a multivariate stepwise binary logistic regression analysis (Wald Method) circulating endothelial microparticles remain significantly associated with pancreas fat content after adjusting for confounding factors, such as tobacco, diabetes mellitus, hypercholesterolemia, or metabolic syndrome. Our results reflect that in essential hypertension, pancreas fat content is superior to liver fat to study beta-cell functionality and insulin resistance. Moreover, the authors described for the first time that pancreas fat content is related to endothelial cell destruction. Further studies are needed to confirm this point.

Body composition and metabolic parameters in men with chronic traumatic paraplegia - A pilot study from India

OBJECTIVE

To study body composition, measures of insulin resistance and dyslipidemia in Indian men with paraplegia as compared to age and body mass index (BMI) matched able-bodied men.

DESIGN

Cross sectional study.

SETTING

Departments of Physical Medicine and Rehabilitation and Endocrinology.

PARTICIPANTS

Males aged 18-45 years with chronic traumatic paraplegia versus age and BMI-matched able-bodied men.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Measures of body composition such as total body fat, lean mass, regional adiposity using dual energy x-ray absorptiometry (DXA), metabolic profile and insulin resistance.

RESULTS

Subjects with paraplegia (n = 43), compared to controls (n = 36), had higher %Fat mass (FM) (25.5 (21.2-28.9) vs 20.2 (15.9-22.2); P < 0.01), lower trunk to leg ratio (0.66 (0.51-0.73) vs 0.87 (0.72-0.94); P < 0.01), lower lean mass index (14.38 (2.57) vs 17.80 (2.34); P < 0.01) and lower appendicular lean mass index (5.81 ± 1.26 vs 8.17 ± 1.12; P < 0.01). Fasting blood glucose (mg/dl) was higher (89.0(81.5-96.5) vs 80.0 (74.5-88.2); P < 0.01), Homeostasis model assessment of insulin resistance was higher (1.33 (1.03-2.12) vs 0.94 (0.52-1.78); P = 0.02), Quantitative insulin sensitivity check index (QUICKI) was lower (0.36 ± 0.04 vs 0.38 ± 0.05; P = 0.02) and HDL-C was lower (33.00 (30.00-42.75) vs 38.50 (33.00-43.25); P < 0.02) in cases compared to controls. QUICKI correlated positively with HDL-C and negatively with %FM, estimated VAT volume and TG. Trunk to leg ratio correlated positively with TG even after controlling for %FM.

CONCLUSION

Men with chronic paraplegia had lower lean mass, higher total and regional fat mass, increased insulin resistance and low HDL-C when compared with BMI-matched able-bodied controls. Both total and regional adiposity correlated with poor metabolic profile.

Comparative Informativity of Computing Methods of Insulin Resistance Assessment

We conducted a comparative study of the calculated indices of insulin resistance HOMA-R, Caro, FGIR, and QUICKI in 29 healthy volunteers (mean age 26.21±0.93 years) with normal body mass index (23.34±0.55 kg/m2). Among the used methods for insulin resistance assessment, QUICKI is the only method that has characteristics required for the diagnostic criterium: low variability coefficient, 100% reproducibility, and minimum coefficient of variation.

High prevalence of early (1st trimester) gestational diabetes mellitus in Polish women is accompanied by insulin resistance similar to women with polycystic ovary syndrome (PCOS)

AIMS

Both pregnancy and polycystic ovary syndrome (PCOS) constitute insulin-resistant states that are associated with an increased prevalence of glucose intolerance. Some women demonstrate significant insulin resistance (IR) and develop gestational diabetes (GDM) even in 1st trimester. We compared surrogate IR indices in 1st trimester pregnant women and in women with PCOS (Rotterdam consensus criteria).

SUBJECTS & METHODS

We performed 75 g Oral Glucose Tolerance Test (OGTT) with insulin measurements in 106 healthy 1st trimester pregnant women at 9.9±2.6 weeks of gestation and in 418 women with PCOS. We assessed IR (HOMA-IR, QUICKI, Matsuda, Belfiore and Stumvoll indices) as well as prevalence of GDM according to the IADPSG and WHO (1999) criteria.

RESULTS

Despite slightly lower BMI (p=0.027) pregnant women had either similar (QUICKI, Belfiore index, Stumvoll0-120 min) or greater IR than women with PCOS (e.g. HOMA-IR 3.85±6.11 versus 2.64±2.04, p=0.002), while only Matsuda index demonstrated less IR in pregnant women (p=0.003). Correlation between IR indices in pregnant women showed marked variability ranging from r=0.334 (HOMA-IR versus Belfiore index) to r=-1.0 (HOMA-IR versus QUICKI, p<0.001). This was accompanied by high prevalence of GDM (14.2% and 9.4%, IADPSG and WHO criteria, respectively). Women with GDM diagnosed according to IADPSG criteria demonstrated greater IR than pregnant women without GDM. In women with GDM diagnosed according to WHO (1999) criteria these differences were visible only for OGTT-derived IR indices (Belfiore, Matsuda and Stumvoll0-120 index).

CONCLUSIONS

Depending on the choice of IR indices healthy 1st trimester pregnant women demonstrate either similar, or greater IR than women with PCOS and this is accompanied by high prevalence of early GDM. It remains to be established whether GDM screening should be performed in the 1st trimester.

Correlation of Surrogate Markers of Insulin Resistance with Fasting Insulin in Type 2 Diabetes Mellitus Patients: A Study of Malwa Population in Punjab, India

Context Insulin resistance (IR) and abnormal insulin secretion play a key role for the development of type 2 diabetes mellitus (DM). Aims We investigated the surrogate markers of IR, i.e., Homeostasis Model Assessment (HOMA), Quantitative Insulin Sensitivity Check Index (QUICKI), McAuley, and Fasting Insulin Resistance Index (FIRI) in type 2 DM patients. Also, fasting insulin (FI) levels were estimated in type 2 diabetics. Further, the correlation of FI with other surrogate markers of IR in type 2 DM was done. Settings and Design A hundred newly diagnosed patients with type 2 DM from Malwa population, Punjab, were considered for evaluation. Another 100 healthy individuals (age and sex-matched) were examined as controls. Methods and Material Fasting blood glucose, FI, and lipid profile were estimated, and IR was calculated using McAuley index (McA), HOMA, QUICKI, and FIRI. Statistical Analysis Used The statistical analysis was performed on the above-mentioned clinical interpretations. The Cohen's kappa test was used to affirm the agreement. Results FI levels in patients with type 2 diabetes were significantly higher (20.8 ± 9.05 µIU/L) than controls (7.93 ± 1.01 µIU/L). IR by surrogate markers was found significant in the study group. The 76% patients with type 2 diabetes ended up as resistant to insulin by FI measurement, almost equivalent to McA, 80%; HOMA, 88%; FIRI, 88%; and QUICKI, 90%. A notable correlation was highlighted between FI and McA manifesting IR ( p < 0.01, r = -0.85). We calculated the statistical correlation of FI with HOMA, QUICKI, and FIRI indices ( p < 0.01, r = 0.93; p < 0.01 r = -0.92; and p < 0.01, r = +0.93, respectively). The agreement visible from Cohen's kappa test also affirms the same ( k = 0.9 for McA). Conclusion We concluded that all the surrogate markers for IR were specific when compared with FI, but in terms of sensitivity McA was found to be more sensitive as it includes markers of dyslipidemia, which is the precipitating factor of metabolic derangements so as the IR in type 2 DM.

Serum Irisin Levels and its Association with Blood Glucose and Insulin Indices in Diagnosing Insulin Resistance in Adolescents with Polycystic Ovarian Syndrome

Context:

Irisin, a new myokine, has been found to be a biological marker of insulin resistance (IR). There is conflicting evidence on serum irisin level in adult women with polycystic ovarian syndrome (PCOS), and data are lacking in adolescents with PCOS.

Aims:

We aimed to evaluate serum Irisin levels and study its association with indices using blood glucose and insulin levels in adolescents with PCOS.

Settings and Design:

This case–control study was conducted in the gynecology outpatient department.

Materials and Methods:

This study was carried out from August 2015 to June 2017. Eighty-two adolescent girls aged 15–19 years were included in the study. Fasting irisin, insulin,blood glucose; 2nd-h insulin (HOMA2-IR), and Quantitative Insulin Sensitivity Check Index (QUICKI) for all participants with addition of 2^nd-h blood glucose for cases.

Statistical Analysis:

A correlation between serum irisin level and various biochemical parameters was done using Pearson's correlation.

Results:

Fasting serum irisin was significantly higher among PCOS cases (8.43 [5.84, 13.11]) when compared to controls 4.90 (2.37, 9.09), median (interquartile range) (P = 0.002). Serum irisin was found to have a significant moderate positive correlation with 2^nd-h blood glucose, fasting/2^nd-h insulin, and HOMA2-IR. A significant moderate negative correlation was observed between irisin and QUICKI.

Conclusions:

Serum irisin levels were significantly elevated in adolescents with PCOS when compared to the controls. A significant correlation of serum irisin with blood glucose and insulin indices indicates that serum irisin could serve as a marker of IR and may help in its diagnosis in adolescents with PCOS.

Role of inflammatory markers in polycystic ovaries syndrome: In relation to insulin resistance

OBJECTIVE

To evaluate the relationship between plasma levels of the inflammatory markers tumor necrosis factor-alpha (TNF-α), C reactive protein (CRP), and interlukin-6 (IL-6) with insulin resistance in Saudi women with polycystic ovaries syndrome (PCOS).

METHODS

One hundred eighty Saudi women with and without PCOS, aged 22-38 years, were randomly recruited in this age and body mass index matched case-control study. Clinical assessment, anthropometric measurements, and biochemical parameters were determined for all study participants.

RESULTS

Levels of TNF-α, IL-6, hs-CRP, insulin, and insulin resistance indices were significantly higher among PCOS group than their age and BMI matched controls (p < 0.05). Results showed that only QUICK-I (β = -0.247, p < 0.0001, 95% CI: -3.009 to -0.977) independently predicted TNF-α levels after adjustment for potential confounders.

CONCLUSIONS

Elevated plasma levels of TNF- α and IL-6 among PCOS women reflects a state of chronic inflammation with potential implication for insulin resistance, independent of obesity.

No Association between 25-Hydroxyvitamin D and Insulin Resistance or Thyroid Hormone Concentrations in a Romanian Observational Study

Background and objectives: Vitamin D is involved in insulin resistance through genomic and non-genomic mechanisms. Several observational and randomized studies have discrepant results; some of them showed an improved insulin resistance (IR), and others a neutral effect after vitamin D deficiency is corrected. Materials and Methods: We designed a retrospective observational study that included all women who presented for 33 months in an outpatient clinic in Bucharest, Romania. Results: We analyzed 353 patients with a mean age of 58.5 ± 13.7 years, a mean body mass index (BMI) of 27.36 ± 4.87 kg/m^-2, and a mean level of 25-hydroxyvitamin D (25OHD) of 39.53 ± 15.73 ng/mL. There were no differences in the calculated Homeostatic Model Assessment of Insulin Resistance variants 1 and 2 (HOMA-IR) and the Quantitative Insulin Sensitivity Check Index (QUICKI) between women with vitamin D deficit versus normal values. In multivariate analysis, there was no significant relation between 25OHD and the response variables considered by us. Conclusions: We observed a small positive correlation between a higher level of 25OHD and increased glycosylated hemolobin (HbA1c) or IR indices without clinical significance. Other modifiable or non-modifiable factors override 25OHD influence on IR in adult women with a normal serum level and may contribute to the remainder of the variability observed.

Herring Milt and Herring Milt Protein Hydrolysate Are Equally Effective in Improving Insulin Sensitivity and Pancreatic Beta-Cell Function in Diet-Induced Obese- and Insulin-Resistant Mice

Although genetic predisposition influences the onset and progression of insulin resistance and diabetes, dietary nutrients are critical. In general, protein is beneficial relative to carbohydrate and fat but dependent on protein source. Our recent study demonstrated that 70% replacement of dietary casein protein with the equivalent quantity of protein derived from herring milt protein hydrolysate (HMPH; herring milt with proteins being enzymatically hydrolyzed) significantly improved insulin resistance and glucose homeostasis in high-fat diet-induced obese mice. As production of protein hydrolysate increases the cost of the product, it is important to determine whether a simply dried and ground herring milt product possesses similar benefits. Therefore, the current study was conducted to investigate the effect of herring milt dry powder (HMDP) on glucose control and the associated metabolic phenotypes and further to compare its efficacy with HMPH. Male C57BL/6J mice on a high-fat diet for 7 weeks were randomized based on body weight and blood glucose into three groups. One group continued on the high-fat diet and was used as the insulin-resistant/diabetic control and the other two groups were given the high-fat diet modified to have 70% of casein protein being replaced with the same amount of protein from HMDP or HMPH. A group of mice on a low-fat diet all the time was used as the normal control. The results demonstrated that mice on the high-fat diet increased weight gain and showed higher blood concentrations of glucose, insulin, and leptin, as well as impaired glucose tolerance and pancreatic β-cell function relative to those on the normal control diet. In comparison with the high-fat diet, the replacement of 70% dietary casein protein with the same amount of HMDP or HMPH protein decreased weight gain and significantly improved the aforementioned biomarkers, insulin sensitivity or resistance, and β-cell function. The HMDP and HMPH showed similar effects on every parameter except blood lipids where HMDP decreased total cholesterol and non-HDL-cholesterol levels while the effect of HMPH was not significant. The results demonstrate that substituting 70% of dietary casein protein with the equivalent amount of HMDP or HMPH protein protects against obesity and diabetes, and HMDP is also beneficial to cholesterol homeostasis.

Prevalence of Insulin Resistance in the Hungarian General and Roma Populations as Defined by Using Data Generated in a Complex Health (Interview and Examination) Survey

Data mainly from one-off surveys clearly show that the health of Roma, the largest ethnic minority of Europe, is much worse than that of the general population. However, results from comprehensive exploratory studies are missing. The aim of our study was to create a complex database for comparative and association studies to better understand the background of the very unfavourable health of Roma, especially the high burden of cardiometabolic diseases. A three-pillar (questionnaire-based, physical and laboratory examinations) health survey was carried out on randomly selected samples of the Hungarian general (HG, n = 417) and Roma (HR, n = 415) populations, and a database consisting of more than half a million datapoints was created. Using selected data, the prevalence rates of metabolic syndrome (MetS) and of its components were determined, and to estimate the risk of insulin resistance (IR), surrogate measures (the homeostasis model assessment of insulin resistance index, quantitative insulin sensitivity check index, McAuley and TyG indices and the TG/HDL-C ratio) were calculated. Receiver operating characteristic curve analysis and Youden’s method were used to define the optimal cut-off values of each IR index. The prevalence of MetS was very high in both study populations (HG: 39.8%, HR: 44.0%) with no statistically significant difference between the two groups in females or males. The prevalence of MetS showed a very marked increase in the HR 35–49 years age group. Among surrogate measures, the TyG index showed the greatest power for predicting IR/MetS at a cut-off value of 4.69 (77% sensitivity, 84% specificity) and indicated a 42.3% (HG) and 40.5% (HR) prevalence of IR. The prevalence of MetS and IR is almost equally very unfavourable in both groups; thus, the factors underlying the high premature mortality burden of Roma should be further clarified by investigating the full spectrum of risk factors available in the database, with a special focus on the access of Roma people to preventive and curative health services.

SPISE and other fasting indexes of insulin resistance: risks of coronary heart disease or type 2 diabetes. Comparative cross-sectional and longitudinal aspects

Background: Fasting insulin resistance indexes are used extensively nowadays. We intended to analyze a new recently presented fasting index, SPISE (sensitivity formula: 600 × HDL-cholesterol^0.185/triglycerides^0.2/BMI^1.338), in comparison with three previously known fasting indexes, regarding correlation with the insulin clamp index, and for the predictive effects of future long-term risks of coronary heart disease (CHD) or manifest type 2 diabetes.Methods: A total of 1049 71-year-old male subjects from the Swedish ULSAM study, median follow-up 8 years, were included. All subjects performed the euglycemic insulin clamp, and analyses of four fasting insulin resistance indexes: SPISE-IR (= 10/SPISE), QUICKI-IR, Log HOMA-IR, and Revised QUICKI-IR.Results: Spearman correlation coefficients with the insulin clamp were 0.60-0.62 for all indexes. Area under curve at ROC analysis was 0.80 for SPISE-IR, and 0.84 for QUICKI-IR, Log HOMA-IR, and Rev QUICKI-IR. Adjusted hazard ratios per 1 SD index increase for long-term risk CHD were similar in all patients: 1.20-1.24 (p = 0.02-0.03). However, comparing the highest quartile (recommended to define insulin resistance) with the lower quartiles, SPISE-IR was the strongest and the only statistically significant insulin resistance index: HR 1.53 (p = 0.02). Adjusted odds ratios per 1 SD index increase for long-term risk of type 2 diabetes were fairly similar (p < 0.001) in all patients: 1.62 for SPISE-IR, 1.97 for QUICKI-IR and Log HOMA-IR, and 2.04 for Rev QUICKI-IR, and also when comparing the highest versus the lower quartiles: 2.8-3.1 (p < 0.001).Conclusion: SPISE, easily applicable, performed equally well as other fasting insulin indexes previously recommended for clinical use, regarding correlation with the insulin clamp, and as predictor for future long-term risks of CHD or type 2 diabetes.

[Índices para la evaluación de la resistencia a la insulina en individuos mexicanos sin diabetes]

Objective

To evaluate the correlation between subrogate index for the evaluation of insulin resistance with the M value obtained with the euglycemic-hyperinsulinemic clamp as well as their sensitivity, specificity, and positive and negative predictive values.

Method

The euglycemic-hyperinsulinemic clamp was performed in subjects having both normal fasting glucose and glycated hemoglobin concentrations. HOMA-IR, QUICKI, HOMA2%S, TyG, TyG*body mass index (BMI) and triglyceride/HDL indexes were calculated. Correlations coefficients were estimated between indexes results and the M-value adjusted by fat-free mass. Areas under the ROC curve were constructed to evaluate overall performance, sensitivity, specificity and predictive values of the subrogate indexes.

Results

57 subjects, 68.4% women, with a mean age of 32.9 ± 11 years-old were included. The subrogate index with the best correlation with the M value was HOMA2%S (r = 0.428), HOMA-IR had the greatest area under the ROC curve (0.683; 95 % confidence interval: 0.503-0.864) and TyG*BMI the best sensitivity (98.2 %) and specificity (51.1 %).

Conclusions

The surrogated indexes for the evaluation of insulin resistance show a significant correlation with the M value obtained with the gold standard. Additional studies are required to determine cut-off values in Mexican population.

Plasma Apelin Unchanged With Acute Exercise Insulin Sensitization

Blood glucose and insulin responses to aerobic exercise are well defined yet the mechanisms effecting post-exercise insulin sensitization remain incomplete. Apelin has been reported to enhance glucose uptake and insulin sensitivity in vivo, but its role as a regulator of insulin sensitivity following acute aerobic exercise has not been investigated. Therefore, the purpose of this study was to investigate apelin's response to acute bouts of maximal and submaximal aerobic exercise and to elucidate apelin's influence on insulin sensitivity. Twelve (22.8 ± 2.9 yrs) healthy male (n = 7) and female (n = 5) subjects completed a graded to maximal (VO₂max) and submaximal (70-75% VO₂max) treadmill running bouts, as well as a 50g glucose challenge (GC). Blood was obtained at four time points (pre, post, 1hr post and 24hrs post) and assessed for glucose, insulin and apelin. Hepatic insulin sensitivity was assessed at rest and at 1hr and 24hrs via HOMA-IR and QUICKI indices. Results demonstrated that plasma apelin did not significantly change by condition (p = 0.324) or time (p = 0.633). Blood glucose and plasma insulin were significantly elevated immediately after VO₂max and GC, but remained stable after submaximal exercise. Insulin sensitivity was significantly improved 1hr post-submaximal exercise, per HOMA-IR (p = 0.034) and QUICKI (p = 0.018) indices. Plasma apelin was significantly correlated with plasma insulin (r = 0.699, p = 0.011), HOMA-IR (r = 0.626, p = 0.029) and QUICKI (r = 0.660, p = 0.019) at rest. We conclude that, although hepatic insulin sensitivity was improved 1hr post-submaximal exercise, this exercise-induced insulin sensitization occurred independent of plasma apelin changes.

Relationship between surrogate estimates and direct measurement of insulin resistance in women with polycystic ovary syndrome

PURPOSE

To evaluate the relationship between surrogate estimates of insulin resistance and a direct measurement of insulin-mediated glucose uptake women with and without PCOS.

METHODS

Retrospective cohort study of 75 PCOS and 118 controls. Fasting plasma glucose and insulin concentrations, insulin resistance as determined by the insulin suppression test, calculation of multiple surrogate estimates of insulin resistance, total and free testosterone concentrations, and correlations between the direct measure and surrogate estimates of insulin resistance were evaluated.

RESULT(S)

Surrogate markers of insulin resistance were correlated to a variable, but statistically significant degree with the direct measure of insulin resistance in control population and the women with PCOS. There was no correlation between the surrogate estimates of insulin resistance and total or free plasma testosterone concentrations.

CONCLUSION(S)

The surrogate estimates of insulin resistance evaluated were significantly related to a direct measure of insulin resistance, and this was true of both the control population and women with PCOS. The magnitude of the relationship between the surrogate estimates and the direct measurement was comparable and not significantly altered by androgen levels. Fasting plasma insulin concentration seems to be at least as accurate as any other surrogate estimate, and is by far the simplest.

The association of quantitative insulin sensitivity indices (HOMA-IR and QUICKI) with anthropometric and cardiometabolic indicators in adolescents

Introduction

Homoeostasis model assessment (HOMA-IR) and the quantitative insulin sensitivity check index (QUICKI) are used to evaluate insulin resistance. The aim of this study was to investigate the association between quantitative insulin sensitivity indices and anthropometric and cardiometabolic indicators in adolescents.

Material and methods

This descriptive-analytic cross-sectional study was conducted on 80 adolescents aged 12 to 13 years in Isfahan, Iran. Anthropometric, cardiometabolic and QUICKI and HOMA-IR indicators were measured. In the results analysis, Pearson correlation coefficient and regression analysis were used.

Results

There was a significant positive correlation between most of the anthropometric indicators and the HOMA-IR index and a significant negative correlation with QUICKI (all p < 0.0001). Moreover, serum triglyceride level had a significant negative correlation with QUICKI index (R = –0.33, p = 0.002) and systolic blood pressure (R = 0.44, p < 0.0001), and triglyceride level (R = 0.66, p < 0.0001) had a significant positive correlation with HOMA index. The results of these two indices were highly correlated in most of the anthropometric and biochemical indices, except for the waist circumference to the neck circumference ratio and systolic blood pressure, which had a significant positive association with HOMA-IR, but did not show a significant association with QUICKI index.

Conclusions

A significant correlation between anthropometric and cardiometabolic indicators with insulin resistance indices (HOMA-IR and QUICKI) was found. Moreover, the results of these two indices were highly correlated in most of the anthropometric and biochemical indices, except for the waist circumference to the neck circumference ratio and systolic blood pressure.

Are plasma 25-hydroxyvitamin D and retinol levels and one-carbon metabolism related to metabolic syndrome in patients with a severe mental disorder?

There is a scarcity of studies assessing the influence of biomarkers in metabolic syndrome in psychiatric patients. Our aim was to correlate serum or plasma levels of 25-hydroxyvitamin D (25-OH-VD), retinol, vitamin B12 (VB12), folate and homocysteine (Hcy), with the metabolic status, in a sample of 289 outpatients with Schizophrenia or Bipolar Disorder. Logistic regression and multiple linear regressions were performed to assess the ability of biomarkers to predict the presence of MetS, the number of risk factors for MetS, and insulin resistance indexes (HOMA and QUICKI). Regarding the association between biomarkers and the QUICKI index, the model explained 6.8% of the variance, with folate and 25-OH-VD levels contributing significantly to the model. The model predicting the number of MetS risk factors was significant and explained 21.7% of the variance, being 25-OH-VD and retinol the statistically significant factors. As for the impact of biomarkers on MetS, the model was statistically significant, being 25-OH-VD and retinol levels the significant factors.  We report for the first time an association between MetS and both low 25-OH-VD and high retinol concentrations. Inflammation-related biomarkers may help identify patients with a high risk of MetS who might benefit from healthy lifestyle counselling and early intervention.

Insulin Resistance as a Risk Factor for Cutaneous Melanoma. A Case Control Study and Risk-Assessment Nomograms

Insulin resistance and obesity are suggested to have a key role in the molecular pathogenesis of various disorders, including several malignancies. Moreover, insulin resistance has recently been found to be associated with cutaneous and uveal melanoma, while a variable positive correlation between obesity and the risk of cutaneous melanoma was also found at least in men. The present trial aims at confirming whether insulin resistance, assessed with the homeostasis model assessment of insulin resistance (HOMA-IR) and the quantitative insulin sensitivity check index (QUICKI), is a risk factor for cutaneous melanoma. One hundred and thirty patients diagnosed with cutaneous melanoma and 130 age-, sex-, and skin phototype-matched controls were evaluated. At the univariate and multivariate analysis, the diagnosis of cutaneous melanoma was inversely related with insulin resistance (HOMA-IR) and positively with BMI (p = 0.0014 and p = 0.008, respectively). Consistently, insulin sensitivity (QUICKI) and BMI resulted positively associated with the diagnosis of cutaneous melanoma (p = 0.0001 and p = 0.0026, respectively). The results obtained are partially in agreement with those reported in the literature. By comparing our data with those generated by other studies, inconsistencies in key features among subgroups of different trials have emerged, possibly affecting final correlations. Based on insulin resistance/sensitivity, fasting insulinemia/glycemia, and BMI values collected from patients who participated in the present trial, two nomograms potentially assessing the risk of cutaneous melanoma have been generated. Molecular aspects sustain a role for insulin resistance in the carcinogenesis of cutaneous melanoma, but clinical data remain uncertain. Larger, well-balanced, correlative trials are still needed to define the potential role of insulin resistance in the carcinogenesis of cutaneous melanoma.

Insulin Resistance in Children

Insulin resistance (IR) is a pathological condition strongly associated with obesity. However, corticosteroids or growth hormone therapy and genetic diseases may affect insulin sensitivity lifelong. In obese children and adolescents of any age there is an evident association between IR and an increased prevalence of type 2 diabetes (T2D) and other elements contributing to the metabolic syndrome, leading to a higher cardiovascular risk. Therefore, early diagnosis and interventions in the attempt to prevent T2D when glycemia values are still normal is fundamental. The gold standard technique used to evaluate IR is the hyperinsulinemic euglycemic clamp, however it is costly and difficult to perform in clinical and research sets. Therefore, several surrogate markers have been proposed. Although the treatment of insulin resistance in children is firstly targeted to lifestyle interventions, in selected cases the integration of a pharmacological intervention might be taken into consideration. The aim of this review is to present the current knowledge on IR in children, starting with an outline of the recent evidences about the congenital forms of deficiency in insulin functioning and therefore focusing on the physiopathology of IR, its appropriate measurement, consequences, treatment options and prevention strategies.

Comparison of various steady state surrogate insulin resistance indices in diagnosing metabolic syndrome

BACKGROUND

Insulin resistance is core cause of metabolic syndrome. Determining insulin resistance is one of the foremost requirements imperative to understanding the pathophysiology of disease. The gold standard "Euglycaemic clamp test" is cumbersome, long and non-feasible in routine clinical setups to diagnose metabolic syndrome. Various continuous and steady state insulin resistance indices are now available in literature. We plan to evaluate commonly utilized steady state insulin resistance indices directly and Homeostasis Model Assessment for Insulin Resistance (HOMAIR) with added triglyceride (HOMA-TG index).

METHODS

The cross-sectional study was carried from Jan-2016 to Dec-2018 at PNS HAFEEZ and department of chemical pathology, AFIP with following objectives: (1) To evaluate steady state insulin resistance markers for diagnosing metabolic syndrome as per IDF defined criteria by ROC curve analysis, (2) to measure Kendal Concordance between various insulin resistance indices and (3) to correlate steady state insulin resistance markers with anthropometric and lipid indices. After several exclusions we selected 224 subjects based upon "non-probability convenience sampling" for inclusion in study. Clinical history, anthropometric measures were calculated and sampling was done for insulin, glucose and other biochemical parameters. Metabolic syndrome was diagnosed as per IDF criteria, while HbA1c was utilized to diagnose diabetes mellitus. Pearson correlation was used to correlate various steady state insulin resistance indices including HOMAIR, HOMA2 index, QUICKI, G/I ratio, HOMA-TG index and serum insulin. AUC was calculated by ROC analysis for all surrogate insulin measures in diagnosis of metabolic syndrome.

RESULTS

"HOMA-TG index" has shown the highest AUC for diagnosing metabolic syndrome along with higher correlation with lipid markers and anthropometric indices in comparison to other steady-state insulin resistance markers. Furthermore, QUICKI and G/I ratio showed the lowest AUC for detection of metabolic syndrome.

CONCLUSION

"HOMA-TG index" has shown highest AUC for metabolic syndrome diagnosis. However, QUICKI and G/I ration showed the lowest AUC for detection of metabolic syndrome. It is hoped that the potential "HOMA-TG index" may provide better diagnostic efficiency for diagnosing metabolic syndrome.

Assessment of insulin sensitivity and secretion in patients with fibrocalculous pancreatic diabetes

Background: Fibrocalculous pancreatic diabetes (FCPD) is a secondary form of diabetes seen in patients with tropical chronic pancreatitis. Insulin deficiency plays a major role in the etiopathogenesis of FCPD. Limited data suggest a possible role of insulin resistance (IR) in the pathogenesis of FCPD. Sparse data exist on measures of insulin sensitivity (IS) and secretion in patients with FCPD and its comparison to type 2 diabetes mellitus (T2D) patients. Method: Eighty patients with FCPD, 36 patients with T2D and 36 healthy subjects were included. A 75 g oral glucose tolerance test (OGTT) was performed in the morning after an overnight fast. We evaluated IS and secretion using indices derived from fasting (homeostasis model assessment of insulin resistance [HOMA-IR], quantitative insulin sensitivity check index [QUICKI] and homeostasis model assessment of beta-cell function [HOMA-ß]) and OGTT (Matsuda, insulin sensitivity index by Kanauchi [ISI-K], oral glucose insulin sensitivity index [OGIS], Stumvoll, insulinogenic index and oral disposition index [ODI]) measurements of glucose and insulin. Results: HOMA-IR was significantly higher and QUICKI significantly lower in patients with FCPD and T2D than in healthy controls (P<0.001). Matsuda, ISI-K, OGIS and Stumvoll were significantly lower in patients with FCPD and T2D than in healthy controls (P<0.001), indicating reduced IS in both FCPD and T2D patients. HOMA-ß, insulinogenic index and ODI were significantly lower in patients with FCPD and T2D compared to healthy controls (P<0.001). Conclusion: FCPD is associated with reduced IS as assessed by fasting and OGTT-based indices. FCPD is also associated with a greater degree of impairment in insulin secretion than in T2D. IR may play a role in the pathogenesis of FCPD.

The triglyceride-glucose index, an insulin resistance marker in newborns?

The study aims to assess the utility of the triglyceride-glucose index (TyG) as a marker of insulin resistance (IR) in neonates. TyG and the homeostatic model assessment (HOMA-IR) values were compared in 196 singleton, term normoweight and without distress newborns. A Decision Tree procedure (CHAID) was used to classify cases into groups or predict values of a dependent (Ln HOMA-IR) variable. Three nodes were drawn for TyG: ≤ 6.7, > 6.7-7.8 and > 7.8 (p < 0.0001; F = 20.52). The predictability of those TyG values vs HOMA-IR was statistically significant (p < 0.0001). It was neither affected by gender (p = 0.084), glucose challenge test (p = 0.138) classifications nor by the TyG node* glucose challenge test and TyG node*gender interactions (p = 0.456 and p = 0.209, respectively). Glucose, HOMA-IR, and the triglyceride/HDL cholesterol ratio increased progressively from node 1 to 3 for TyG while QUICKI decreased.

CONCLUSION

In conclusion, TyG appears to be a suitable tool for identifying IR at birth, justifying the further insulin determination in those neonates. TyG ≥ 7.8 is recommended as cut-off point in neonates. The need for a follow-up study to confirm the TyG as early IR marker is desirable.

WHAT IS KNOWN

• HOMA-IR and the triglyceride-glucose index (TyG) show a high correlation. • The TyG has been used as an insulin resistance marker in adults.

WHAT IS NEW

• This is the first study where TyG has been assessed in neonates. • TyG appears to be a suitable and cheap tool for identifying insulin resistance at birth.

Limitations of insulin resistance assessment in polycystic ovary syndrome

BACKGROUND

Though insulin resistance (IR) is common in polycystic ovary syndrome (PCOS), there is no agreement as to what surrogate method of assessment of IR is most reliable.

SUBJECTS AND METHODS

In 478 women with PCOS, we compared methods based on fasting insulin and either fasting glucose (HOMA-IR and QUICKI) or triglycerides (McAuley Index) with IR indices derived from glucose and insulin during OGTT (Belfiore, Matsuda and Stumvoll indices).

RESULTS

There was a strong correlation between IR indices derived from fasting values HOMA-IR/QUICKI, r = -0.999, HOMA-IR/McAuley index, r = -0.849 and between all OGTT-derived IR indices (e.g. r = -0.876, for IRI/Matsuda, r = -0.808, for IRI/Stumvoll, and r = 0.947, for Matsuda/Stumvoll index, P < 0.001 for all), contrasting with a significant (P < 0.001), but highly variable correlation between IR indices derived from fasting vs OGTT-derived variables, ranging from r = -0.881 (HOMA-IR/Matsuda), through r = 0.58, or r = -0.58 (IRI/HOMA-IR, IRI/QUICKI, respectively) to r = 0.41 (QUICKI/Stumvoll), and r = 0.386 for QUICKI/Matsuda indices. Detailed comparison between HOMA-IR and IRI revealed that concordance between HOMA and IRI was poor for HOMA-IR/IRI values above 75th and 90th percentile. For instance, only 53% (70/132) women with HOMA-IR >75th percentile had IRI value also above 75th percentile. There was a significant, but weak correlation of all IR indices with testosterone concentrations.

CONCLUSIONS

Significant number of women with PCOS can be classified as being either insulin sensitive or insulin resistant depending on the method applied, as correlation between various IR indices is highly variable. Clinical application of surrogate indices for assessment of IR in PCOS must be therefore viewed with an extreme caution.

Vitamin D Supplementation in Adults with Vitamin D Deficiency and Its Effect on Metabolic Syndrome - A Randomized Controlled Study

BACKGROUND

Inverse relationship between metabolic syndrome (MetS) and 25-hydroxyvitamin D (25(OH) D) levels is controversial. Hypovitaminosis-D has long been suspected as a risk factor for glucose intolerance.

AIM

A randomized double blind placebo controlled study to evaluate effects of vitamin D supplementation on insulin resistance in subjects with hypovitaminosis-D and MetS.

MATERIALS AND METHODS

Subjects were randomized to receive either oral 25(OH) D3 supplement (60000 (IU) per week for 8 weeks followed by 60,000 IU monthly for 4 months) or a placebo for six months. The parameters measured were blood pressure, vitamin D, fasting blood sugar (FBS), insulin, homeostasis model assessment (HOMA), quantitative insulin sensitivity check index (QUICKI), body mass index (BMI), and waist circumference (WC).

RESULTS

There were no significant changes in parameters of vitamin-D group compared to placebo group except serum vitamin-D was significantly increased in vitamin-D group (p < 0.0001). In vitamin-D group, mean WC at baseline was 95.9 ± 6.66, which significantly changed to 94.6 ± 7.47 (p = 0.001). Mean BMI at baseline was 29.1 ± 4.06 which significantly changed to 28.5 ± 4.16 (p = 0.001). The mean vitamin-D concentration at baseline was 15.4 ± 9.03 which significantly (p < .0001) increased to 26.1 ± 11.8. In placebo group mean insulin levels was 10.7 ± 4.81IU / L which increased significantly (p = 0.03) to 15.4 ± 14.0. Mean QUICKI at baseline was 0.34 ± 0.03 which decreased significantly (p = 0.02) to 0.32 ± 0.03.

CONCLUSION

In this study the relationship between vitamin D supplementation and MetS or IR was not established. Whether achieving vitamin D sufficiency in large population-based trials with a longer duration would produce more favorable results needs to be assessed.

Association of sodium intake with insulin resistance in Korean children and adolescents: the Korea National Health and Nutrition Examination Survey 2010

BACKGROUND

This study aimed to evaluate the relationship between sodium intake and insulin resistance indices.

METHODS

A total of 718 Korean children and adolescents (411 boys) aged 10-18 years who participated in the Korea National Health and Nutrition Examination Survey (KNHANES) were included in the study. The urinary sodium to urinary creatinine ratio was used as a surrogate for sodium intake. The homeostatic model assessment of insulin resistance (HOMA-IR) and the quantitative insulin sensitivity check index (QUICKI) were used as indices of insulin resistance.

RESULTS

The mean urinary sodium to urinary creatinine ratio was 11.34 in males and 10.17 in females. The urinary sodium to urinary creatinine ratio was significantly positively correlated with HOMA-IR (r=0.165, p<0.001) and inversely correlated with QUICKI (r=-0.181, p<0.001) in Pearson's correlation analyses. In a multivariate linear regression analysis, the urinary sodium to urinary creatinine ratio was independently and significantly positively associated with HOMA-IR (β=0.073, p=0.018) and significantly inversely associated with QUICKI (β=-0.080, p=0.007) after adjustment for possible confounders. HOMA-IR was independently and significantly positively associated with the urinary sodium to urinary creatinine ratio (β=0.087, p=0.018), whereas QUICKI was independently and significantly negatively associated with the urinary sodium to urinary creatinine ratio (β=-0.097, p=0.009) after controlling for confounders.

CONCLUSIONS

Our results suggest that sodium intake, as estimated by the urinary sodium to urinary creatinine ratio, may be independently associated with insulin resistance in children and adolescents.

Insulin Sensitivity and Insulin Resistance in Non-Diabetic Middle-Aged Patients with Obstructive Sleep Apnoea Syndrome

Background:

Obstructive sleep apnoea syndrome (OSAS) has been linked with abnormal glucose metabolism, insulin resistance (IR) and development of diabetes mellitus.

Methods:

Non-diabetic patients (n=69) with OSAS, diagnosed by polysomnography, were prospectively recruited. To evaluate IR among OSAS patients, the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and Insulin sensitivity by Quantitative Insulin sensitivity Check Index (QUICKI) were used.

Results:

HOMA-IR was positively associated with body-mass index (BMI) (ρ=0.364, p=0.002), time with oxyhaemoglobin saturation <90% (ρ=0.291, p=0.015), arousal index (ρ=0.268, p=0.027), Epworth sleepiness scale (ESS) score (ρ=0.293, p=0.019) and negatively with average oxyhaemoglobin saturation (ρ=-0.398, p=0.001) and minimum oxyhaemoglobin saturation (ρ=-0.327, p=0.006). QUICKI was positively associated with forced vital capacity (r=0.301, p=0.014), average oxyhaemoglobin saturation (r=0.443, p<0.001), minimum oxyhaemoglobin saturation (ρ=0.318, p=0.008), and negatively associated with sleep stage transitions (r=-0.266, p=0.032), oxygen desaturation index (r=-0.404, p=0.005), time with oxyhaemoglobin saturation <90% (r=-0.311, p=0.019), arousal index (r=-0.344, p=0.004) and ESS score (r=-0.299, p=0.016). After adjustment for age and BMI, HOMA-IR was associated with sleep stage transitions, time with oxyhaemoglobin saturation <90%, average oxyhaemoglobin saturation, minimum oxyhaemoglobin saturation and arousal index. QUICKI was associated with oxygen desaturation index, sleep stage transitions, ESS score, minimum oxyhaemoglobin saturation and arousal index.

Conclusions:

An independent association between OSAS and IR in patients without pre-existing diabetes mellitus was observed. Recurrent hypoxia and sleep fragmentation in OSAS are associated with IR in these patients.

The association between tuberculosis and the development of insulin resistance in adults with pulmonary tuberculosis in the Western sub-district of the Cape Metropole region, South Africa: a combined cross-sectional, cohort study

BACKGROUND

The existence of a bi-directional relationship between tuberculosis (TB) and insulin resistance (IR)/diabetes has been alluded to in literature. Although diabetes has been linked to increased tuberculosis risk, the relationship between tuberculosis as a causative factor for IR remains unclear. The study aimed to determine if an association existed between tuberculosis and IR development in adults with newly diagnosed pulmonary tuberculosis at baseline. It was additionally aimed to document changes in IR status during TB follow-up periods.

METHODS

This cross-sectional study evaluated ambulatory participants at baseline for IR prevalence via anthropometry, biochemistry and diagnostic IR tests [homeostasis model assessment-IR (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI)]. A prospective cohort sub-section study was additionally performed on approximately half of the baseline study population, who were followed-up at two and five months whilst on tuberculosis treatment. Summary statistics, correlation co-efficients and appropriate analysis of variance were used to describe and analyse data. Participants were excluded if they presented with other forms of tuberculosis, were HIV-positive, obese or had any pre-disposing IR conditions such as diabetes or metabolic syndrome.

RESULTS

Fifty-nine participants were included from August 2013 until December 2014 (33.95 ± 12.02 years old; 81.4% male). IR prevalence was 25.4% at baseline, determined by a calculated HOMA-IR cut-off point of 2.477. Patients with IR were younger (p = 0.04). Although the difference between IR levels in participants between baseline and follow-up was not significant, a decrease was observed over time. The majority of participants (61.0%) presented with a normal BMI at baseline. Mean baseline values of fasting glucose were within normal ranges (4.82 ± 0.80 mmol/L), whereas increased mean CRP levels (60.18 ± 50.92 mg/L) and decreased mean HDL-cholesterol levels (males: 0.94 ± 0.88 mmol/L; females: 1.14 ± 0.88 mmol/L) were found.

CONCLUSIONS

The study found an association between tuberculosis and IR development in newly diagnosed pulmonary tuberculosis patients. Although not significant, IR levels decreased over time, which could be indicative of a clinical improvement. A high prevalence of IR amongst young tuberculosis patients therefore highlights the need for early identification in order to facilitate a reversal of IR and prevent possible IR-related complications.

Variable reliability of surrogate measures of insulin sensitivity after Roux-en-Y gastric bypass

Roux-en-Y gastric bypass (RYGB) induces weight loss and improves insulin sensitivity when evaluated by the hyperinsulinemic-euglycemic clamp (HEC). Surrogate indices of insulin sensitivity calculated from insulin and glucose concentrations at fasting or after an oral glucose tolerance test (OGTT) are frequently used, but have not been validated after RYGB. Our aim was to evaluate whether surrogate indices reliably estimate changes in insulin sensitivity after RYGB. Four fasting surrogates (inverse-HOMA-IR, HOMA2-%S, QUICKI, revised-QUICKI) and three OGTT-derived surrogates (Matsuda, Gutt, OGIS) were compared with HEC-estimated peripheral insulin sensitivity (R_d or R_d/I, depending on how the index was originally validated) and the tracer-determined hepatic insulin sensitivity index (HISI) in patients with preoperative type 2 diabetes (n = 10) and normal glucose tolerance (n = 10) 1 wk, 3 mo, and 1 yr postoperatively. Post-RYGB changes in inverse-HOMA-IR and HOMA2-%S did not correlate with changes in R_d at any visit, but were comparable to changes in HISI at 1 wk. Changes in QUICKI and revised-QUICKI correlated with R_d/I after surgery. Changes in the Matsuda and Gutt indices did not correlate with changes in R_d/I and R_d, respectively, whereas OGIS changes correlated with R_d changes at 1 yr post-RYGB. In conclusion, surrogate measures of insulin sensitivity may not reflect results obtained with gold standard methodology after RYGB, underscoring the importance of critical reflection when surrogate endpoints are used. Fasting surrogate indices may be particularly affected by post-RYGB changes in insulin clearance, whereas the validity of OGTT-derived surrogates may be compromised by surgical rearrangements of the gut.

The relationship between insulin resistance and periodontitis is not affected by Mediterranean diet in a Spanish population

OBJETIVE

To examine the insulin resistance measured by surrogate indices in subjects with and without periodontitis and to find out any correlation among dietary intake with insulin resistance.

DESIGN

Fifty-five patients were recruited to participate in this cross-sectional study. Insulin resistance measured by the homoeostasis model assessment (HOMA-IR) and the quantitative insulin sensitivity check index moreover glycaemia, creatinine, uric acid, high density lipoproteins, low density lipoproteins, very low density lipoproteins and triglycerides among others. True periodontal disease was elucidated through the examination of probing pocket depth, clinical attachment level, recession of the gingival margin and gingival bleeding. The statistical analyses used were the student's T-test for independent variables, Kolmogorov-Smirnov if variations were homogeneous; if not, the Mann-Whitney U Test was applied instead. Correlations between variables were assessed using Pearson's correlation coefficients. True periodontal disease was confirmed through the greater values of probing pocket depth, clinical attachment level, gingival margin and gingival bleeding in the periodontitis group in comparison with non-periodontitis group.

RESULTS

Insulin resistance was evidenced by the greater values of HOMA-IR as well as by the lower quantitative insulin sensitivity check index values in the periodontitis group. Fasting insulin, glucose, uric acid, creatinine, low density lipoproteins, triglycerides and very low density lipoprotein levels were significant higher in periodontitis group. Pearson's correlations did not show any association among diet data and insulin resistance parameters in periodontitis patients.

CONCLUSION

A putative systemic relationship between insulin resistance and periodontitis exists but it does not seem conceivable any effect of diet over such relationship.

Indexes of Insulin Resistance in Hyperinsulinemic Polycystic Ovary Syndrome in a Macedonian Cohort of Women of Reproductive Age: A Cross-Sectional Study

BACKGROUND:

Polycystic ovary syndrome (PCOS) is complex hormonal, metabolic and reproductive disorder and is a leading cause of female infertility. Hyperinsulinemia secondary to insulin resistance plays important role in the pathogenesis of PCOS.

AIM:

To assess the sensitivity of different indices of insulin resistance and their relevance in a clinical setting.

MATERIAL AND METHODS:

A cross-sectional study of 43 patients with PCOS and 29 noromo ovulatory women as a control group was conducted. Standard clinical, anthropometrical and hormonal testing for hyperandrogenism was conducted, as well as oral glucose tolerance test with determination of basal and stimulated glucose and insulin values.

RESULTS:

The dynamic I/G index showed the highest sensitivity and specificity, but the static indexes HOMA-IR and QUICKI, although based on only basal glycemic and insulinemic values, showed good sensitivity, 90.38% and 94.01% respectively. HOMA-IR showed significant positive correlation with the stimulated insulin values.

CONCLUSIONS:

Our results support the use of static indexes in the evaluation of insulin resistance in women with PCOS in a clinical setting, offering a simple assessment of insulin resistance in PCOS, which holds great prognostic and treatment implications.

Prediction of insulin resistance in type 2 diabetes mellitus using routinely available clinical parameters

AIMS

To determine if insulin resistance (IR), an important predictor of cardiovascular risk in the general population and in type 2 diabetes mellitus, can be assessed using simple parameters which are readily available in clinical practice.

METHODS

This cross-sectional study included 194 patients with type 2 diabetes. Body mass index, waist index (WI), triglyceride levels, 1/HDL, triglyceride/HDL, uric acid and urine albumin:creatinine ratio were investigated as possible predictors of IR.

RESULTS

WI correlated more strongly than any other parameter with log insulin levels, log fasting glucose to insulin ratio (FGIR), log fasting glucose to insulin product (FGIP), homeostatic model assessment (HOMA-IR) and quantitative insulin check index (QUICKI). WI also emerged as the strongest independent predictor of IR indices studied in regression as well as in ROC analyses. At a cut-off of 1.115, WI had a 78% sensitivity and 65% specificity for predicting IR when HOMA-IR was used as indicator of IR, and 74% sensitivity and specificity when QUICKI was used as indicator of IR. Combining WI with other variables did not improve performance significantly.

CONCLUSIONS

In our cohort of patients with type 2 diabetes, WI was the parameter with the strongest association with, and the best predictor of, IR.

In quest for method of insulin resistance assessment in everyday clinical practice-Insulin resistance indices

Insulin resistance (IR) a state of decreased sensitivity of target tissues to insulin is suspected usually in obese so can be overlooked in normal weight subjects thus it is important to find optimal method of IR assessment in clinical practice.

METHODS

HOMA, HOMA2, QUICKI, Matsuda index were calculated using data obtained from medical history of 130 female subjects - patients of the Department of Endocrinology and Metabolic Diseases, in whom oral glucose tolerance test (OGTT) with parallel insulin concentrations assessment was performed.

RESULTS

IR correlated positively with body mass index (BMI) in the entire study group, regardless which of four analyzed IR indices was used. Insulin resistance occurred in the obese as well as in normal weight and underweight subjects. The incidences of IR in the study group varied, depending upon chosen method and adopted cut-off values.

CONCLUSIONS

The need for quantitative assessment of IR in clinical practice is apparent. Proper selection of the best method of IR assessment remains a problem. HOMA appears the method of first choice for clinical use. There is an urgent need to establish universal or, at least, national standard cut-off values for IR, to introduce IR assessment in clinical practice.

In prostate cancer, low adiponectin levels are not associated with insulin resistance

PURPOSE

Adiponectin, an adipose tissue-derived hormone with insulin-sensitizing effect, has been inversely associated with several hormonally dependent malignancies. Prostate cancer is associated with low levels of adiponectin, which have been proposed as an independent risk factor for this malignancy. Aim of this study was to examine whether hypoadiponectinaemia in prostate is associated with insulin resistance.

EXPERIMENTAL DESIGN

Plasma samples and covariate data in the context of a case-control study of 300 Greek men were evaluated including 75 patients with prostate cancer, 75 patients with benign prostatic hyperplasia (BPH) and 150 age-matched healthy controls.

RESULTS

Patients with prostate cancer had significantly lower plasma adiponectin levels compared with the other two groups, that is BPH patients and healthy controls (7.4 ± 5 ng/mL vs. 11.5 ± 6.4 ng/mL and 12.8 ± 8 ng/mL, respectively). On the other hand, no statistically significant differences were found between patients with prostate cancer and the other two groups for both HOMA-IR and QUICKI (P-value = 0.551). As expected, in all three groups, the levels of adiponectin correlated negatively with HOMA-IR (rho = -0.214, P-value = 0.006), QUICKI (rho = 0.214, P-value = 0.006) and insulin levels (rho = 0.942, P-value < 0.001).

CONCLUSION

In spite of what would have been expected from the relevant literature, our data suggest that the hypoadiponectinaemia in prostatic cancer does not appear to be associated with insulin resistance.

Beneficial impact of sleep extension on fasting insulin sensitivity in adults with habitual sleep restriction

STUDY OBJECTIVES

A link between sleep loss and increased risk for the development of diabetes is now well recognized. The current study investigates whether sleep extension under real-life conditions is a feasible intervention with a beneficial impact on glucose metabolism in healthy adults who are chronically sleep restricted.

DESIGN

Intervention study.

PARTICIPANTS

Sixteen healthy non-obese volunteers (25 [23, 27.8] years old, 3 men).

INTERVENTIONS

Two weeks of habitual time in bed followed by 6 weeks during which participants were instructed to increase their time in bed by one hour per day.

MEASUREMENTS AND RESULTS

Continuous actigraphy monitoring and daily sleep logs during the entire study. Glucose and insulin were assayed on a single morning blood sample at the end of habitual time in bed and at the end of sleep extension. Home polysomnography was performed during one weekday of habitual time in bed and after 40 days of sleep extension. Sleep time during weekdays increased (mean actigraphic data: +44 ± 34 minutes, P < 0.0001; polysomnographic data: +49 ± 68 minutes, P = 0.014), without any significant change during weekends. Changes from habitual time in bed to the end of the intervention in total sleep time correlated with changes in glucose (r = +0.53, P = 0.041) and insulin levels (r = -0.60, P = 0.025), as well as with indices of insulin sensitivity (r = +0.76, P = 0.002).

CONCLUSIONS

In healthy adults who are chronically sleep restricted, a simple low cost intervention such as sleep extension is feasible and is associated with improvements in fasting insulin sensitivity.

Correlation Between Glycated Hemoglobin and Homa Indices in Type 2 Diabetes Mellitus: Prediction of Beta-Cell Function from Glycated Hemoglobin

BACKGROUND

The present study aimed to determine the most efficient insulin resistance function related to glycemic control expressed as glycated hemoglobin (HbA1c) in type 2 diabetes mellitus patients (T2DM). The other aim is to derive equations for the prediction of beta cell functions containing HbA1c as a parameter in addition to fasting glucose and insulin.

METHODS

T2DM Patients were grouped according to the following: (1) degree of control (good, fair, and poor control) and (2) insulin resistance as observed in obtained data and significant differences revealed by the homeostasis model assessment (HOMA) of related parameters (insulin resistance = HOMA2IR, beta-cell function = HOMA%B, and insulin sensitivity = HOMA%S) among groups. Correlations and forecasting regression analysis were calculated.

RESULTS

HbA1c was found to be correlated with insulin resistance parameters in T2DM subgroups. This correlation was also significantly correlated with HOMA%B and the quantitative insulin sensitivity check index (QUICKI) in fair and poor control groups. Regression analysis was used to predict the forecasting equations for HOMA%B. The best applicable equations were derived for healthy control (HOMA2%B=-1.76*FBG+5.00*Insulin+4.69*HbA1c+189.84) and poor control groups (HOMA2%B=0.001* FBG+0.5*Insulin-8.67*HbA1c+101.96). These equations could be used to predict β-cell function (HOMA%B) after FBG, insulin and HbA1c values were obtained for healthy and poor control groups. In the good and fair control groups, the applicability of the HOMA model fails to yield appropriate results.

CONCLUSIONS

Beta-cell function is correlated with QUICKI and HbA1c and could be predicted properly from HbA1c, insulin, and glucose in the healthy and poor control groups. New regression equations were established that involve HbA1c.

Normal pregnancy- a state of insulin resistance

BACKGROUND

Purpose of insulin resistance (IR) adapted by mother is to deliver enough quantity of nutrients to the growing fetus. Many maternal hormones and factors play role in causation of IR during pregnancy.

AIM

The study aims at evaluating IR at different trimesters of pregnancy.

MATERIALS AND METHODS

Pregnant women at 1(st), 2(nd) and 3(rd) trimester were grouped into groups I, II and III respectively (n=20 in each group). Healthy non-pregnant women were taken as controls (n=30). Fasting plasma glucose (FPG) and fasting serum insulin (FSI) were measured and IR indices such as fasting glucose to insulin ratio (FGIR), quantitative insulin sensitivity check index (QUICKI), log FSI and log HOMA1-IR were calculated. The student's t-test and one way Analysis of variance (ANOVA) were used for data analysis.

RESULTS

The mean FSI, log FSI and log HOMA 1-IR were significantly higher in 2(nd) and 3(rd) trimesters while QUICKI was significantly lower in 2(nd) and 3(rd) trimesters of pregnancy when compared with controls. Also, mean FGIR was found to be significantly lower in 3rd trimester when compared with controls.

CONCLUSION

As pregnancy advances, IR increases. Increased IR is associated with poor maternal and fetal outcome. Screening of all pregnancy for IR and early intervention may help to reduce the associated complications.

Normal pregnancy- a state of insulin resistance

BACKGROUND

Purpose of insulin resistance (IR) adapted by mother is to deliver enough quantity of nutrients to the growing fetus. Many maternal hormones and factors play role in causation of IR during pregnancy.

AIM

The study aims at evaluating IR at different trimesters of pregnancy.

MATERIALS AND METHODS

Pregnant women at 1(st), 2(nd) and 3(rd) trimester were grouped into groups I, II and III respectively (n=20 in each group). Healthy non-pregnant women were taken as controls (n=30). Fasting plasma glucose (FPG) and fasting serum insulin (FSI) were measured and IR indices such as fasting glucose to insulin ratio (FGIR), quantitative insulin sensitivity check index (QUICKI), log FSI and log HOMA1-IR were calculated. The student's t-test and one way Analysis of variance (ANOVA) were used for data analysis.

RESULTS

The mean FSI, log FSI and log HOMA 1-IR were significantly higher in 2(nd) and 3(rd) trimesters while QUICKI was significantly lower in 2(nd) and 3(rd) trimesters of pregnancy when compared with controls. Also, mean FGIR was found to be significantly lower in 3rd trimester when compared with controls.

CONCLUSION

As pregnancy advances, IR increases. Increased IR is associated with poor maternal and fetal outcome. Screening of all pregnancy for IR and early intervention may help to reduce the associated complications.

Estimation of insulin sensitivity in children: methods, measures and controversies

Insulin resistance is defined as a state where insulin produces a diminished biological response, primarily in its capacity as a glucose-regulating hormone. Insulin resistance is commonly diagnosed by pediatric clinicians, but is rarely measured directly in children or adolescents. This review provides an overview of the techniques that can be used to assess insulin sensitivity in children, summarizing the methods involved, the assumptions, pitfalls, and appropriate uses of each technique, as well as their validation and reproducibility in pediatric samples.

Irisin in patients with nonalcoholic fatty liver disease

OBJECTIVE

Irisin is a recently discovered myokine proposed to increase thermogenesis-related energy expenditure and improve metabolism. We aimed to comparatively evaluate serum irisin levels in patients with biopsy-proven nonalcoholic fatty liver disease (NAFLD) vs. controls and study their association with disease severity.

METHODS

Fifteen and 16 consecutively enrolled patients with biopsy-proven nonalcoholic simple steatosis (NAFL) and steatohepatitis (NASH), respectively, and 24 lean and 28 obese controls without NAFLD were recruited. Irisin, established adipokines and biochemical tests were measured.

RESULTS

Serum irisin levels were statistically different in obese controls (33.7±2.7 ng/mL; p<0.001) and patients with NAFL (30.5±1.5 ng/mL; p<0.001) and NASH (35.8±1.9 ng/mL; p=0.001) compared with lean controls (47.7±2.0 ng/mL), but were similar among patients with NAFL, NASH and obese controls. This difference remained significant after adjustment for body mass index (or waist circumference), gender, age, insulin resistance (assessed by HOMA-IR or QUICKI), exercise and time since blood collection. Serum leptin and adiponectin, but not irisin, levels were independently from BMI correlated with insulin resistance and cardiometabolic factors. Serum irisin tended to be higher in patients with (36.7±2.4 ng/mL) than without (30.8±1.2 ng/mL; p=0.02) portal inflammation and independently associated with the latter; these data need to be confirmed by future studies.

CONCLUSIONS

Serum irisin levels differ between lean controls and obese controls or NAFLD patients. Despite similar circulating irisin levels between NAFL and NASH groups, irisin may be independently and positively associated with the presence of portal inflammation. Future clinical and mechanistic studies are needed to confirm and extend these data.

Cinnamon may have therapeutic benefits on lipid profile, liver enzymes, insulin resistance, and high-sensitivity C-reactive protein in nonalcoholic fatty liver disease patients

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent cause of hepatic injury in the world. One of the most important therapeutic strategies for this disease is modulating insulin resistance and oxidative stress. In this study, we investigated the hypothesis that supplementation with cinnamon exerts an insulin sensitizer effect in patients with NAFLD. In a double-blind, placebo-controlled trial with two parallel groups, fifty patients with NAFLD were randomized to receive daily supplementation with either two capsules of cinnamon (each capsule contain 750 mg cinnamon) or 2 placebo capsules, daily for 12 weeks. During the intervention, all patients were given advice on how to implement a balanced diet and physical activity into their daily lives. In the treatment group (P < .05), significant decreases in HOMA (Homeostatic Model Assessment) index, FBS (fasting blood glucose), total cholesterol, triglyceride, ALT (alanine aminotransferase), AST (aspartate aminotransferase), GGT (gamma glutamine transpeptidase), and high-sensitivity C-reactive protein were seen, but there was no significant change in serum high-density lipoproteins levels (P = .122). In both groups, low-density lipoproteins decreased significantly (P < .05). In conclusion, the study suggests that taking 1500 mg cinnamon daily may be effective in improving NAFLD characteristics.

Salt loading exacerbates diastolic dysfunction and cardiac remodeling in young female Ren2 rats

OBJECTIVE

Recent data would suggest pre-menopausal insulin resistant women are more prone to diastolic dysfunction than men, yet it is unclear why. We and others have reported that transgenic (mRen2)27 (Ren2) rats overexpressing the murine renin transgene are insulin resistant due to oxidative stress in insulin sensitive tissues. As increased salt intake promotes inflammation and oxidative stress, we hypothesized that excess dietary salt would promote diastolic dysfunction in transgenic females under conditions of excess tissue Ang II and circulating aldosterone levels.

MATERIALS/METHODS

For this purpose we evaluated cardiac function in young female Ren2 rats or age-matched Sprague-Dawley (SD) littermates exposed to a high (4%) salt or normal rat chow intake for three weeks.

RESULTS

Compared to SD littermates, at 10weeks of age, female Ren2 rats fed normal chow showed elevations in left ventricular (LV) systolic pressures, LV and cardiomyocyte hypertrophy, and displayed reductions in LV initial filling rate accompanied by increases in 3-nitrotyrosine content as a marker of oxidant stress. Following 3weeks of a salt diet, female Ren2 rats exhibited no further changes in LV systolic pressure, insulin resistance, or markers of hypertrophy but exaggerated increases in type 1 collagen, 3-nitrotryosine content, and diastolic dysfunction. These findings occurred in parallel with ultrastructural findings of pericapillary fibrosis, increased LV remodeling, and mitochondrial biogenesis.

CONCLUSION

These data suggest that a diet high in salt in hypertensive female Ren2 rats promotes greater oxidative stress, maladaptive LV remodeling, fibrosis, and associated diastolic dysfunction without further changes in LV systolic pressure or hypertrophy.

Life-long endurance exercise in humans: circulating levels of inflammatory markers and leg muscle size

Human aging is associated with a loss of skeletal muscle and an increase in circulating inflammatory markers. It is unknown whether endurance training (Tr) can prevent these changes. Therefore we studied 15 old trained (O-Tr) healthy males and, for comparison, 12 old untrained (O-Un), 10 Young-Tr (Y-Tr) and 12 Young-Un (Y-Un). Quadriceps size, VO2 peak, CRP, IL-6, TNF-α and its receptors, suPAR, lipid profile, leucocytes and glucose homeostasis were measured. Tr was associated with an improved insulin profile (p<0.05), and lower leucocyte (p<0.05) and triglyceride levels (p<0.05), independent of age. Aging was associated with poorer glucose control (p<0.05), independent of training. The age-related changes in waist circumference, VO2 peak, cholesterol, LDL, leg muscle size, CRP and IL-6 were counteracted by physical activity (p<0.05). A significant increase in suPAR with age was observed (p<0.05). Most importantly, life-long endurance exercise was associated with a lower level of the inflammatory markers CRP and IL-6 (p<0.05), and with a greater thigh muscle area (p<0.05), compared to age-matched untrained counterparts. These findings in a limited group of individuals suggest that regular physical endurance activity may play a role in reducing some markers of systemic inflammation, even within the normal range, and in maintaining muscle mass with aging.

Is there a skeletal muscle mass threshold associated with the deterioration of insulin sensitivity in sedentary lean to obese postmenopausal women?

AIM

The purpose of this study was to determine an optimal cut-off point of skeletal muscle mass, using appendicular lean body mass (LBM) index, that identifies at risk individuals with deteriorated insulin sensitivity, using an established quantitative insulin sensitivity index (QUICKI) cut-off.

METHODS

We performed a cross-sectional analysis in 231 lean and obese (BMI: 18.7-51.0 kg/m(2)) menopausal women. Fasting plasma glucose and insulin were obtained to calculate QUICKI as an index of insulin sensitivity. Skeletal muscle mass was measured as appendicular LBM by DXA and expressed as appendicular LBM index [appendicular LBM (kg)/height (m(2))]. Cut-offs were determined using receiver operating characteristic (ROC) curve analyses.

RESULTS

The best cut-off value for skeletal muscle mass index to identify menopausal women with reduced insulin sensitivity was 7.025 kg/m(2) which had a sensitivity of 69.5% and specificity of 58.2%.

CONCLUSION

Our results suggest that sedentary postmenopausal women with an appendicular skeletal muscle mass index above 7.025 kg/m(2) may be at greater risk of insulin resistance. Prospective studies are needed to validate our result.

Comparison of insulin sensitivity measures in South Asians

OBJECTIVE

South Asians have increased visceral adiposity, insulin resistance and greater prevalence of type 2 diabetes and cardiovascular disease when compared to Caucasians of European origin. Surrogate markers of insulin resistance such as the composite insulin sensitivity (Matsuda) index correlate with glucose clamps in other populations, but ethnicity can affect these indices. We compared the Matsuda index, homeostasis model assessment (HOMA-IR), quantitative insulin sensitivity check index (QUICKI), and triglyceride/HDL ratio to insulin sensitivity derived from euglycemic clamps in healthy South Asians and Caucasians.

MATERIALS/METHODS

Twenty-three healthy South Asians and 18 Caucasians matched for age (mean±SE=33.6±2.1 vs. 36.0±3.0 years) and BMI (25.2±1.1 vs. 24.6±0.9 kg/m(2)) underwent 75 g oral glucose tolerance test (OGTT), 2-h euglycemic hyperinsulinemic clamp (240 pmol·m(-2)·min(-1)), fasting lipid profile, and anthropometric measures.

RESULTS

South Asians had higher fasting insulin (41±5 vs. 21±2 pmol/l; p=0.002) and lower HDL-C (1.25±0.06 vs. 1.56±0.10 mmol/l; p=0.010), but similar fasting glucose (5.0±0.1 vs. 4.9±0.1 mmol/l) levels vs. Caucasians. South Asians had significantly decreased measures of insulin sensitivity derived from both the euglycemic clamp (24.9±1.3 vs. 41.4±1.9 μmol·kg(-1)·min(-1); p<0.0001) and OGTT (Matsuda Index 7.60±0.99 vs. 13.60±1.79; p=0.004). The Matsuda index correlated highly with clamp insulin sensitivity in South Asians (r=0.50; p=0.014) and Caucasians (r=0.47; p=0.046). HOMA-IR, QUICKI, and triglyceride/HDL ratio correlated with clamp values in South Asians, but not in Caucasians.

CONCLUSIONS

In South Asians, Matsuda index, HOMA-IR, QUICKI, and triglyceride/HDL ratio offer simple and valid surrogate measures of insulin sensitivity that can be employed in larger clinical or epidemiological studies in this ethnic group.

Association of estrogen receptor alpha gene polymorphisms with metabolic syndrome in Egyptian women

OBJECTIVE

Metabolic syndrome is a risk factor for coronary heart diseases as well as diabetes, fatty liver and several cancers. The prevalence of metabolic syndrome in women appears to be increasing, particularly in women of childbearing age. In the present study, we assessed the association of estrogen receptor-alpha gene polymorphisms (XbaI and PvuII) with metabolic syndrome and its related phenotypes.

MATERIALS/METHODS

One hundred and fifty Egyptian female patients with metabolic syndrome (mean age 35.52±6.86) were compared with one hundred and fifty age matched healthy Egyptian women (controls). The component traits of metabolic syndrome were determined, and the XbaI and PvuII genotypes were assessed with the PCR-RFLP method.

RESULTS

Our data indicated a significant difference in the allele frequencies of XbaI, but not PvuII, between the metabolic syndrome and control groups (P=0.0003 and P=0.164). Carriers of the minor alleles of XbaI and PvuII gene polymorphisms, in either the homozygous or heterozygous form, were associated with high diastolic blood pressure, high total cholesterol and LDL-c levels, increased HOMA-IR values and decreased QUICKI values compared to carriers of the major allele. However, only the minor G allele of XbaI was associated with measures of adiposity, specifically, BMI and waist circumference.

CONCLUSIONS

The XbaI polymorphism of the estrogen receptor alpha gene is associated with metabolic syndrome. On the other hand, PvuII gene polymorphism is not associated with the occurrence of the disease in this sample of Egyptian women.

Dyslipidemia, but not hyperglycemia and insulin resistance, is associated with marked alterations in the HDL lipidome in type 2 diabetic subjects in the DIWA cohort: impact on small HDL particles

In this study we have used mass spectrometry in order to characterize the HDL lipidome in three groups of women from the DIWA cohort; one control group, plus two groups with type 2 diabetes with insulin resistance; one dyslipidemic and one normolipidemic. The aim was to investigate whether dyslipidemia is required in addition to insulin resistance for the occurrence of an altered HDL lipidome, which in turn might impact HDL functionality. The dyslipidemic type 2 diabetic subjects were distinguished by obesity, hypertriglyceridemia with elevated apoC3, low HDL-cholesterol and chronic low grade inflammation. In a stepwise multivariate linear regression analysis, including biomarkers of dyslipidemia and insulin resistance as independent variables, only dyslipidemia showed a significant correlation with HDL lipid classes. Small HDL-particles predominated in dyslipidemic subjects in contrast to the normolipidemic diabetic and control groups, and were enriched in lysophosphatidylcholine (+13%), a product of proinflammatory phospholipases, and equally in two core lipids, palmitate-rich triacylglycerols and diacylglycerols (+77 %), thereby reflecting elevated CETP activity. Dyslipidemic small HDL particles were further distinguished not only as the primary carrier of ceramides, which promote inflammation and insulin resistance, but also by a subnormal plasmalogen/apoAI ratio, consistent with elevated oxidative stress typical of type 2 diabetes. From these data we conclude that in type 2 diabetes, dyslipidemia predominates relative to hyperglycemia for the occurrence of an altered HDL lipidome. Furthermore, dyslipidemia alters the cargo of bioactive lipids, with implications for HDL function.

Effects of rye and whole wheat versus refined cereal foods on metabolic risk factors: a randomised controlled two-centre intervention study

BACKGROUND & AIMS

Intervention studies investigating the effects of wholegrain intake on glucose and insulin metabolism have provided conflicting results. Aim of this study was the evaluation of glucose and insulin metabolism in response to long-term consumption of rye and whole wheat compared with a diet containing the same amount of refined cereal foods, in individuals with metabolic syndrome from two European locations (Kuopio-Finland/Naples-Italy).

METHODS

146 individuals of both genders, age range 40-65 years with metabolic syndrome, were recruited to this study with parallel groups. After a 2-4 week run-in period, participants were assigned to a diet based on wholegrain (wholegrain group) or on refined cereal products (control group), each one for a duration of 12 weeks. Peripheral insulin sensitivity, assessed by FSIGT, lipids and inflammatory markers were measured before and at the end of intervention.

RESULTS

61 participants in the control group and 62 in the wholegrain group completed the dietary intervention. Compliance to the two diets was good. At the end of the intervention, insulin sensitivity indices and secretion (SI, QUICKI, DI, dAIRG) and lipids and inflammatory markers did not change significantly in the wholegrain and control groups as compared with baseline and no differences between the two groups were observed.

CONCLUSIONS

Wholegrain cereal foods consumption compared with refined cereals for 12 weeks did not affect peripheral insulin sensitivity. The study was registered with ClinicalTrials.gov identifier NCT00945854.