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Background: Novel therapeutics for inflammatory bowel disease (IBD) are under development, yet mechanistic readouts at the tissue level are lacking. Techniques to assess intestinal immune composition could represent a valuable tool for mechanism of action (MOA) studies of novel drugs. Mass cytometry enables analysis of intestinal inflammatory cell infiltrate and corresponding molecular fingerprints with unprecedented resolution. Here, we aimed to optimize the methodology for isolation and cryopreservation of cells from intestinal tissue to allow for the potential implementation of mass cytometry in MOA studies., Methods: We investigated key technical issues, including minimal tissue requirements, cell isolation protocols, and cell storage, using intestinal biopsies and peripheral blood from healthy individuals. High-dimensional mass cytometry was employed for the analyses of biopsy-derived intestinal cellular subsets., Results: Dithiothreitol and mechanical dissociation decreased epithelial cell contamination and allowed for isolation of adequate cell numbers from 2 to 4 colonic or ileal biopsies (6 × 104±2 × 104) after a 20-minute collagenase digestion, allowing for reliable detection of most major immune cell subsets. Biopsies and antibody-labeled mononuclear cells could be cryopreserved for later processing and acquisition (viability > 70%; P < 0.05)., Conclusions: Mass cytometry represents a unique tool for deep immunophenotyping intestinal cell composition. This technique has the potential to facilitate analysis of drug actions at the target tissue by identifying specific cellular subsets and their molecular signatures. Its widespread implementation may impact not only IBD research but also other gastrointestinal conditions where inflammatory cells play a role in pathogenesis.

Aims: To investigate whether in type 1 diabetes (T1DM) patients the concomitance of long-lasting celiac disease (CD) treated with a gluten free diet (GFD) impacts glycaemic control and the prevalence/severity of microvascular complications., Methods: A case-control, observational study was performed in 34 patients with T1DM and GFD-treated CD and 66 patients with T1DM alone matched for age, gender, and T1DM duration. Anthropometric parameters, glucose control (HbA1 c ), status of chronic complications and concomitant autoimmune diseases were evaluated., Results: HbA1 c level was similar in T1DM + CD and T1DM alone (7.8 ± 1.0 vs 7.7 ± 1.1%, P = 0.57); insulin requirement was significantly higher in T1DM + CD compared with T1DM (P = 0.04). There were no differences in systolic blood pressure while diastolic blood pressure was significantly lower in T1DM + CD (P = 0.003). The prevalence/severity of microvascular complications was similar between the two groups. Glomerular filtration rate (eGFR) was significantly lower in T1DM + CD (100 ± 20 vs 110 ± 16 ml/min/1.73 m 2 , P = 0.007)., Conclusions: In patients with T1DM, the co-occurrence of long-term GFD-treated CD neither worsens glycemic control nor negatively impacts chronic microvascular complications. However, patients with T1DM + CD have lower eGFR values than those with T1DM alone., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Context: Diabetes mellitus is associated with gastrointestinal (GI) motility dysfunction, ranging from delayed to accelerated gastric emptying (GE)., Objective: To evaluate GE in patients with type 1 diabetes mellitus (T1DM) without chronic complications and to investigate its relation with postprandial glucose and GI hormone responses., Design: Cross-sectional study., Setting/participants: Forty-two patients with T1DM free of chronic complications referred to Federico II University and 31 healthy controls similar for age, sex, and body mass index., Interventions/main Outcome Measures: GE was assessed by using the 13C-octanoate breath test with a standardized solid meal. During the meal, plasma glucose, ghrelin, and glucagon-like peptide 1 (GLP-1) responses were assessed, and GI symptoms were evaluated by a specific questionnaire., Results: Patients with T1DM showed a significantly slower GE half-emptying time (GE t1/2) (113 ± 34 minutes) than did controls (89 ± 17 minutes; P < 0.001). Thirty-six percent of T1DM showed a delayed GE (t1/2 > 120 minutes), whereas all controls showed a normal GE. When patients with T1DM were stratified according to GE t1/2, postmeal glucose response was significantly different between those with delayed and those with normal GE (P = 0.013). In particular, patients with T1DM and delayed GE showed a significantly longer mean time to peak glucose than did patients with normal GE (P = 0.004). In addition, GE t1/2 was an independent predictor of the time to peak glucose (β = 0.329; P = 0.025). GLP-1 and ghrelin responses to the test meal, as well as the prevalence of GI symptoms, were similar between patients with T1DM and controls and between patients with T1DM with normal GE and those with delayed GE., Conclusions: Delayed GE time is associated with a longer time to peak glucose. GE evaluation could be useful for individualizing the timing of preprandial insulin bolus in patients with T1DM.

Multiple acyl-CoA dehydrogenation deficiency (MADD) is an inborn disorder of fatty acid oxidation due to a defect in electron transfer to the respiratory chain. We describe the medical/nutritional management of a successful pregnancy in a 19-year-old woman with a known diagnosis of MADD. A high-carbohydrate, low-fat, six-meal diet supplemented with protein was prescribed to meet the nutritional needs during pregnancy. L-Carnitine supplementation was also progressively increased over the weeks. Serum acyl-carnitine profile revealed raised levels of chain-length C6-C14, which remained substantially unchanged during pregnancy. Serum amino acid profile was in the normal range indicating an adequate nutritional support. Pregnancy progressed uneventful and the patient gave birth to a healthy boy without any complication.A careful clinical monitoring associated with an adequate medical/nutritional management may improve pregnancy outcome in women with MADD.

Bariatric surgery is recognized as a highly effective therapy for obesity since it accomplishes sustained weight loss, reduction of obesity-related comorbidities and mortality, and improvement of quality of life. Overall, bariatric surgery is associated with a 42% reduction of the cardiovascular risk and 30% reduction of all-cause mortality. This review focuses on some nutritional consequences that can occur in bariatric patients that could potentially hinder the clinical benefits of this therapeutic option. All bariatric procedures, to variable degrees, alter the anatomy and physiology of the gastrointestinal tract; this alteration makes these patients more susceptible to developing nutritional complications, namely, deficiencies of macro- and micro-nutrients, which could lead to disabling diseases such as anemia, osteoporosis, protein malnutrition. Of note is the evidence that most obese patients present a number of nutritional deficits already prior to surgery, the most important being vitamin D and iron deficiencies. This finding prompts the need for a complete nutritional assessment and, eventually, an adequate correction of pre-existing deficits before surgery. Another critical issue that follows bariatric surgery is post-operative weight regain, which is commonly associated with the relapse of obesity-related co-morbidities. Nu-tritional complications associated with bariatric surgery can be prevented by life-long nutritional monitoring with the administration of multi-vitamins and mineral supplements according to the patient's needs., Competing Interests: Conflict-of-interest statement: The authors declare that there were no conflicts of interest.

Background: Laparoscopic sleeve gastrectomy (LSG) is becoming the most performed bariatric procedure; however, data available on long-term follow-up are scanty., Objectives: The aim of the present study was to evaluate the 5-year efficacy of LSG on weight loss, gastroesophageal reflux disease (GERD) symptoms, and obesity-associated co-morbidities., Setting: Tertiary-care referral hospital., Methods: This study retrospectively analyzed 105 obese patients undergoing LSG from January 2006 to December 2009. The preoperative evaluation included demographic characteristics, evaluation of co-morbidities, a double-contrast barium swallow, and an upper-gastrointestinal endoscopy. The following data were collected at 1, 3, and 5 years after surgery: weight, improvement/remission of co-morbidities, complications, and revisional surgery., Results: According to preoperative body mass index (BMI), patients were divided into Group 1 (n = 61) with BMI≤50 kg/m(2) and Group 2 (n = 44) with BMI>50 kg/m(2). The follow-up rate was 94% after 5 years (n = 99). Delta BMI (BMI at follow-up-preoperative BMI) was significantly higher in Group 2 than in Group 1 at 1-3 years and 5 years (P<.001). Furthermore, at 5 years, Group 2 showed a significantly higher percentage total weight loss (%TWL) (26.6%±18.3% versus 33.5%±12.9%, P = .006) than Group 1, whereas percentage excess weight loss was similar (58.4%±21.8% versus 55.3%±19.5%, P = .5).Younger age at surgery and absence of postoperative GERD were associated with a better %TWL at 5 years (P<.001 and P = .03)., Conclusion: LSG is an effective procedure at long-term, with good weight loss outcomes and with a considerable improvement of obesity-associated co-morbidities. Younger age at surgery and absence of postoperative GERD were associated with a better %TWL at 5 years., (Copyright © 2016 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Over half of BRAFV600E melanomas display intrinsic resistance to BRAF inhibitors, in part due to adaptive signaling responses. In this communication we ask whether BRAFV600E melanomas share common adaptive responses to BRAF inhibition that can provide clinically relevant targets for drug combinations. We screened a panel of 12 treatment-naïve BRAFV600E melanoma cell lines with MAP Kinase pathway inhibitors in pairwise combination with 58 signaling inhibitors, assaying for synergistic cytotoxicity. We found enormous diversity in the drug combinations that showed synergy, with no two cell lines having an identical profile. Although the 6 lines most resistant to BRAF inhibition showed synergistic benefit from combination with lapatinib, the signaling mechanisms by which this combination generated synergistic cytotoxicity differed between the cell lines. We conclude that adaptive responses to inhibition of the primary oncogenic driver (BRAFV600E) are determined not only by the primary oncogenic driver but also by diverse secondary genetic and epigenetic changes ("back-seat drivers") and hence optimal drug combinations will be variable. Because upregulation of receptor tyrosine kinases is a major source of drug resistance arising from diverse adaptive responses, we propose that inhibitors of these receptors may have substantial clinical utility in combination with inhibitors of the MAP Kinase pathway.

Background: In head and neck squamous cell carcinoma (HNSCC), resistance to single-agent targeted therapy may be overcome by co-targeting of compensatory signaling pathways., Methods: A targeted drug screen with 120 combinations was used on 9 HNSCC cell lines., Results: Multiple novel drug combinations demonstrated synergistic growth inhibition. Combining the insulin-like growth factor-1 receptor (IGF-1R) inhibitor, BMS754807, with either the human epidermal growth factor receptor (HER)-family inhibitor, BMS599626, or the Src-family kinase inhibitor, dasatinib, resulted in substantial synergy and growth inhibition. Depending on the cell line, these combinations induced synergistic or additive apoptosis; when synergistic apoptosis was observed, AKT phosphorylation was inhibited to a greater extent than either drug alone. Conversely, when additive apoptosis occurred, AKT phosphorylation was not reduced by the drug combination., Conclusion: Combined IGF-1R/HER family and IGF-1R/Src family inhibition may have therapeutic potential in HNSCC. AKT may be a node of convergence between IGF-1R signaling and pathways that compensate for IGF-1R inhibition., (© 2015 Wiley Periodicals, Inc.)

Context: Idiopathic reactive hypoglycemia (IRH) is characterized by recurrent episodes of symptomatic hypoglycemia occurring within 4 hours after meals. The underlying mechanisms remain obscure., Objective: This study aimed to investigate the response of the glucoregulatory and gastrointestinal hormones to an oral glucose load (OGTT) in individuals with documented IRH., Design and Setting: This was a cross-sectional study composed of outpatients referred to "Federico II" University of Naples., Patients: We enrolled subjects with IRH documented by a mixed meal under ordinary life conditions and healthy subjects as controls., Main Outcome Measure: We measured plasma glucose, insulin, glucagon-like peptide 1 (GLP-1), GIP, and glucagon response to a 75-g OGTT in cases and controls., Results: Ten IRH and eight control subjects were enrolled. During the OGTT, mean plasma glucose tended to be lower in IRH than in control subjects, reaching a statistically significant difference at 240 minutes (T240) (43 ± 1.6 vs 72 ± 0.3 mg/dL; P = .001). Accordingly, the insulin response was higher in IRH than in control subjects (P < .019) with a statistically significant difference (46%) at T90 (P = .045) and was associated with significantly lower glucagon levels in the late phase of the OGTT: at T120 (P = .031) and T180 (P = .048) in IRH than in control subjects. A greater GLP-1 response was found among IRH compared with control subjects (P = .005); GLP-1 peak was 2-fold higher in IRH individuals (9.77 ± 2.52 pmol/L) than in the control group (4.19 ± 0.53 pmol/L; P = .041). In the IRH group, GLP-1 peak inversely correlated with the nadir of plasma glucose (r = -0.66; P = .039). A multivariate analysis confirmed that GLP-1 peak independently predicted the plasma glucose nadir (β = -0.593; P = .026)., Conclusions: GLP-1 may play a significant role in the pathogenesis of idiopathic IRH.

Background: Phenylketonuria (PKU) is an autosomal recessive disorder caused by the deficiency of phenylalanine hydroxylase that catalyzes the conversion of phenylalanine to tyrosine, using tetrahydrobiopterin (BH4) as coenzyme. Besides dietary phenylalanine restriction, new therapeutic options are emerging, such as the treatment with BH4 in subgroups of PKU patients responding to a loading test with BH4., Methods: A no-profit open-label interventional trial with long-term oral BH4 therapy, sponsored by the Italian Medicines Agency (AIFA), was performed in a group of 17 PKU patients resulted as BH4 responders among 46 subjects analyzed for BH4-responsiveness (prot. FARM5MATC7). We report on efficacy and safety data of BH4 therapy and analyze factors predicting BH4-responsiveness and long-term response to BH4. A BH4-withdrawal test was used as a proof of the efficacy of long-term therapy with BH4., Results: Forty-four percent of the patients responded to the 48 h-long loading test with BH4. All the phenotypic classes were represented. Genotype was the best predictor of responsiveness, along with lower phenylalanine levels at diagnosis, higher tolerance and lower phenylalanine/tyrosine ratio before the test. In BH4 responder patients, long-term BH4 therapy resulted safe and effective in increasing tolerance while maintaining a good metabolic control. The BH4 withdrawal test, performed in a subset of patients, showed that improved tolerance was directly dependent on BH4 assumption. Tolerance to phenylalanine was re-evaluated in 43.5% of patients and was longitudinally analyzed in 5 patients., Conclusions: Long-term treatment with BH4 is safe and effective in increasing tolerance to phenylalanine. There is real need to assess the actual tolerance to phenylalanine in PKU patients to ameliorate quality of life, improve nutritional status, avoiding unnecessarily restricted diets, and interpret the effects of new therapies for PKU.

Objectives: To investigate the anthropometric and metabolic correlates of different patterns of left ventricular (LV) geometry in a cohort of outpatient children with high prevalence of obesity., Study Design: Anthropometric measures, lipid profile, blood pressure (BP), fasting plasma glucose (FPG), and echocardiographic variables were evaluated in 281 white children (6-16 years), of whom 105 were obese and 105 were morbidly obese. Patterns of LV geometry were defined as follows: normal geometry, eccentric LV hypertrophy (LVH), concentric LV remodeling, and concentric LVH., Results: One hundred forty-eight children exhibited normal LV geometry, 53 eccentric LVH, 36 concentric LV remodeling, and 44 concentric LVH. The 4 groups differed in body mass index, waist circumference, waist-to-height ratio, triglycerides/high-density lipoprotein cholesterol ratio (Tg/HDL-C), and BP (P < .05-.0001). A statistically significant impairment of diastolic function (expressed as greater E/E', P < .002) was observed across patterns of LV geometry. Among anthropometric measures, waist-to-height ratio showed better performance in relation to LVH, with an optimal cut-point of 0.58, compared with body mass index and waist circumference. Children with concentric LVH exhibited the worst metabolic risk profile, with greater prevalence of visceral obesity, high Tg/HDL-C, high BP, and high-normal FPG, than children with normal LV geometry., Conclusions: In children with high levels of obesity, an unfavorable "cardiometabolic phenotype" can be identified, which includes concentric LVH, visceral obesity, high BP, high Tg/HDL-C, and high-normal FPG., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Rationale: The rationale was to utilize a bioinformatics approach to identify miRNA binding sites in genes with single nucleotide mutations (SNPs) to discover pathways in heart failure (HF)., Objective: The objective was to focus on the genes containing miRNA binding sites with miRNAs that were significantly altered in end-stage HF and in response to a left ventricular assist device (LVAD)., Methods and Results: BEDTools v2.14.3 was used to discriminate SNPs within predicted 3'UTR miRNA binding sites. A member of the miR-15/107 family, miR-16, was decreased in the circulation of end-stage HF patients and increased in response to a LVAD (p<0.001). MiR-16 decreased Vacuolar Protein Sorting 4a (VPS4a) expression in HEK 293T cells (p<0.01). The SNP rs16958754 was identified in the miR-15/107 family binding site of VPS4a which abolished direct binding of miR-16 to the 3'UTR of VPS4a (p<0.05). VPS4a was increased in the circulation of end-stage HF patients (p<0.001), and led to a decrease in the number of HEK 293T cells in vitro (p<0.001)., Conclusions: We provide evidence that miR-16 decreases in the circulation of end-stage HF patients and increases with a LVAD. Modeling studies suggest that miR-16 binds to and decreases expression of VPS4a. Overexpression of VPS4a decreases cell number. Together, these experiments suggest that miR-16 and VPS4a expression are altered in end-stage HF and in response to unloading with a LVAD. This signaling pathway may lead to reduced circulating cell number in HF.

Objective: To evaluate the relationship between estimated glomerular filtration rate (eGFR) and cardiometabolic risk factors (CMRF) in an outpatient pediatric population with high prevalence of obesity., Design and Methods: eGFR was evaluated in 901 children unselected for chronic kidney disease of whom 694 were overweight/obese (6-16 years) and 207 were age- and sex-matched normal weight (NW). We generated three categories of eGFR: mild-low eGFR (< 20th percentile), high eGFR (>80th percentile) and intermediate eGFR (20-80th percentile), considered as the reference category, Results: Children with either mild-low or high eGFR category showed a 2-4 fold higher Odds ratio of high blood pressure, left ventricular hypertrophy, and microalbuminuria compared with children of the intermediate eGFR category. In addition, children with mild-low eGFR levels showed a 1.5-2 fold higher Odds ratio of impaired fasting glucose and high white blood cell count compared with children with intermediate eGFR levels., Conclusions: In outpatient children with high prevalence of obesity, children with either mildly reduced or high eGFR have an increased burden of CMRF. Children with eGFR < 97 mL/min/1.73 m² show a worse CMR profile. This finding supports the usefulness to assess eGFR to identify children with unfavorable CMR profile.

Objective: To evaluate whether impaired fasting glucose (IFG) or the combination of IFG and impaired glucose tolerance (IGT) is associated with progressive abnormalities of cardiac geometry and function., Research Design and Methods: We studied 562 nondiabetic (311 women), nonhypertensive participants of the second Strong Heart Study exam, without prevalent cardiovascular (CV) disease and with estimated glomerular filtration rate ≥60 mL/min/1.73 m(2) (age 46-65 years, 198 with isolated IFG [35%], and 132 with combined IFG and IGT [23%]). Anthropometric parameters, insulin resistance, fibrinogen, C-reactive protein (CRP), lipid profile, blood pressure (BP), and echocardiographic parameters were compared with 232 participants with normal glucose tolerance (NGT)., Results: BMI, prevalence of central obesity, homeostatic model assessment index of insulin resistance, plasma triglycerides, fibrinogen, and CRP increased progressively across categories of glucose intolerance (P < 0.0001), with the IFG+IGT group having higher values than those with isolated IFG (0.05 < P < 0.0001). Compared with NGT, both IFG and IFG+IGT exhibited greater left ventricular (LV) mass (P < 0.0001) and lower Doppler early peak rapid filling velocity to peak atrial filling velocity ratio (P < 0.005), without differences in LV systolic function. The odds of LV hypertrophy (LV mass index >46.7 in women or >49.2 g/m(2.7) in men) was 3.5 in IFG participants (95% CI 0.68-17.76; P = NS) and 9.76 (2.03-46.79; P = 0.004) in IFG+IGT, compared with NGT, after adjustment for age, sex, heart rate, systolic BP, and waist circumference (WC). In the overall sample, LV mass index was associated with WC (P = 0.033), CRP (P = 0.027), and 2-h oral glucose tolerance test (P = 0.001) independently of confounders., Conclusions: Cardiometabolic profile and markers of inflammation are more severely altered in men and women with both IFG and IGT compared with those with IFG alone. These individuals, in the absence of hypertension, have a 10-fold greater probability of preclinical CV disease (LV hypertrophy).

Objective: To evaluate whether the high triglyceride-to-HDL cholesterol (TG-to-HDL-C) ratio is associated with cardiometabolic risk (CMR) factors and preclinical signs of organ damage in an outpatient population of white children and adolescents., Research Design and Methods: The study population included 884 subjects (aged 6-16 years), of whom 206 (23%) were normal weight, 135 (15%) were overweight, and 543 (61%) were obese. Biochemical variables were analyzed in the whole sample, whereas homocysteine and left ventricular (LV) geometry and function were evaluated in 536 and 258 children, respectively., Results: The percentage of pubertal children (P < 0.001), as well as measurements of BMI, waist circumference, homeostasis model assessment of insulin resistance, white blood cell count, alanine aminotransferase (ALT), systolic blood pressure (P < 0.0001, for all), creatinine (P < 0.001), and diastolic blood pressure (P < 0.02), increased from the lowest to the highest tertile of the TG-to-HDL-C ratio. Age, sex, homocysteine, and glomerular filtration rate did not change. Moreover, interventricular septum thickness, relative wall thickness, and LV mass index (P = 0.01 to P < 0.0001) increased across tertiles of the TG-to-HDL-C ratio. Children with a TG-to-HDL-C ratio ≥2.0 showed a two- to threefold higher risk of elevated ALT levels and concentric LV hypertrophy than those with a TG-to-HDL-C ratio <2.0, independent of confounding factors., Conclusions: The high TG-to-HDL-C ratio is associated with several CMR factors and preclinical signs of liver and cardiac abnormalities in the outpatient, white pediatric population. Thus, a TG-to-HDL-C ratio ≥2.0 may be useful in clinical practice to detect children with a worsened CMR profile who need monitoring to prevent cardiovascular disease in adulthood.

Background: Sleeve gastrectomy (SG) was pioneered as a two-stage intervention for super and super-super obesity to minimize morbidity and mortality; it is employed increasingly as a primary procedure. Early outcomes and integrity of laparoscopic SG (LSG) against leak using a technique incorporating gastric transection-line reinforcement were studied., Methods: Between 2003 and 2009, 121 patients underwent LSG (16, two-stage; 105, primary). Of the patients, 66% were women, mean age 38.8 ± 10.9 (15.0-64.0), and body mass index (BMI, kg/m(2)) 48.7 ± 9.3 (33.7-74.8). Bovine pericardium (Peri-Strips Dry [PSD]) was used to reinforce the staple line. Parametric and nonparametric tests were used, as appropriate. The paired t test was used to assess change from baseline; bivariate analyses and logistic regression were used to identify preoperative patient characteristics predictive of suboptimal weight loss., Results: Mean operative time was 105 min (95-180), and mean hospitalization was 5.6 days (1-14). There was no mortality. There were 6 (5.0%) complications: 1 intraoperative leak, 1 stricture, 1 trocar-site bleed, 1 renal failure, and 2 wound infections. There were no postoperative staple-line leaks. Following 15 concomitant hiatal hernia operations, 3 (20%) recurred: 1 revised to RYGB and 2 in standby. Two post-LSG hiatal hernias of the two-stage series required revisions because of symptoms. BMI decreased 24.7% at 6 months (n = 55) to 37.5 ± 9.3 (22.2-58.1); %EWL was 48.1 ± 19.3 (15.5-98.9). Twelve-month BMI (n = 41) was 38.4 ± 10.5 (19.3-62.3); %EWL was 51.7 ± 25.0 (8.9-123.3). Forty-eight-month BMI (n = 13) was 35.6 ± 6.8 (24.9-47.5); %EWL was 61.1 ± 12.2 (43.9-82.1) (p < 0.001). Preoperative BMI was predictive of >70% of patients who experienced <50% EWL at 6 months. At 2 weeks, 100% of type 2 diabetes patients (n = 23) were off medication (mean HbA(1C), 5.9 ± 0.5%; glycemia, 90.0 ± 19.9 mg/dL (p < 0.01) at 3 months)., Conclusions: Laparoscopic PSD-reinforced LSG as a staged or definitive procedure is safe and effective in the short term and provides rapid type 2 diabetes mellitus reduction with a very low rate of complications.

Objective: To evaluate whether fasting plasma glucose (FPG) within a normoglycemic range is associated with cardiometabolic risk factors (CMRF) among children and adolescents in an outpatient setting., Research Design and Methods: Subjects (780; age 6-16 years) with FPG <100 mg/dL were divided into tertiles of FPG., Results: BMI, waist circumference, homeostasis model assessment-insulin resistance, systolic blood pressure, and white blood cell (WBC) count (P < 0.0001) increased across tertiles of FPG. Subjects with high-normal FPG (89-99 mg/dL) showed a higher risk of insulin resistance, hypertension, and high WBC count compared with subjects with low-normal FPG, independent of BMI z score., Conclusions: In outpatient children and adolescents, higher FPG within the normal range is associated with several CMRF, independent of obesity. Thus the simple measurement of FPG may help identify subjects who warrant some monitoring in relation to cardiovascular risk.

Background: To evaluate whether the pediatric metabolic syndrome (MetS) or its factors are useful to detect subclinical abnormalities of cardiac, liver, and glomerular damage in an outpatient population., Methods: The population study included 799 children (age 10 ± 3 years, mean ± SD), 24% of whom were normalweight, 25% overweight, and 51% obese. Alanine-aminotransferase (ALT) levels, estimated glomerular filtration rate (eGFR) and HOMA-IR were analyzed in all children. Microalbuminuria (MA) and left ventricular (LV) geometry and function were evaluated in 501 and 247 children, respectively. MetS was defined using Cook's criteria., Results: MetS was diagnosed in 131 children (16%). Children with MetS+ and MetS- were similar for age, gender and Tanner stage distribution. Children with MetS+ showed higher ALT levels (31 ± 19 vs 21 ± 11 IU/L, p<0.0001), LV mass (39 ± 10 vs 34 ± 10 g/h(2.7), p<0.001) and relative wall thickness (0.37 ± 0.06 vs 0.35 ± 0.05, p<0.01) than MetS-. The two groups were similar for MA and eGFR. At multiple logistic regression analysis, children MetS+ showed a higher risk (OR, 95% Cl) adjusted for confounding factors, of high ALT levels (1.71, 1.12-2.59, p=0.012) and concentric LV hypertrophy (2.17, 1.01-4.66, p=0.047) than children MetS-. The risk of preclinical liver and cardiac damage associated with the MetS phenotype was not higher than predicted by its single components., Conclusions: Children with MetS show a 2-fold greater risk of having high ALT levels and concentric LV hypertrophy. However, the risk of subclinical manifestations of liver and cardiac damage can be predicted equally well by the single components of the syndrome., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Alanine aminotransferase (ALT) elevations are considered a surrogate marker of nonalcoholic liver disease and predict later development of diabetes and metabolic syndrome in adults. The aim of the present study is to evaluate the prevalence of high ALT levels in obese children using updated and sex-related cutoff ALT value (ALT >30 IU/L for boys and >19 IU/L for girls). We also analyzed the association between ALT levels and metabolic factors in the 2 sexes. Three-hundred fifty-eight obese children (168 boys and 190 girls; age range, 6-16 years) were studied. Inclusion criteria were as follows: obesity, defined by an individual body mass index (BMI) greater than or equal to the 95th percentile for age and sex; negativity of markers for viral hepatitis; and no alcohol consumption. Two hundred six nonobese children (92 boys and 114 girls; age range, 6-16 years) served as a control group for ALT levels. The percentage of obese children with elevated ALT was 36% in boys and 55% in girls. Obese boys with ALT greater than 30 IU/L showed higher mother's BMI (P < .025), BMI, waist circumference, insulin resistance evaluated with homeostasis model assessment (HOMA-IR) index (P < .0001, for all), and systolic and diastolic blood pressure (P < .025, for both) compared with those with ALT not exceeding 30 IU/L. The ALT levels correlated positively with mother's BMI, BMI, waist circumference, HOMA-IR, triglycerides, and blood pressure. In linear regression analysis, waist circumference was the only independent factor associated with ALT level (beta = 0.370, t = 3,905, P < .0001). Obese girls with ALT greater than 19 IU/L exhibited lower age (P < .025) and higher triglycerides (P < .0001) than girls with ALT not exceeding 19 IU/L. The ALT levels correlated positively with triglycerides and HOMA-IR and negatively with age and Tanner stage. In linear regression analysis, ALT levels were independently associated only with triglycerides (beta = 0.330, t = 4.588, P < .0001). Our study shows that a high proportion of obese children present elevated ALT levels. This abnormality is associated in boys, more than in girls, with preclinical traits of the metabolic syndrome. The adoption of sex-related cutoff of ALT levels is desirable also for the pediatric population.

Background and Aims: We evaluated whether hyperinsulinemia and/or insulin resistance are independently associated with plasma lipids, uric acid and blood pressure in non-diabetic subjects., Methods and Results: A database of non-diabetic Italian subjects has recently been set up using data from hyperinsulinemic euglycemic clamp studies carried out using the standard technique (40 mU per min per square meter of body surface area). In this database we evaluated the relationships between fasting plasma insulin (FPI), glucose metabolized during clamp (M) and plasma levels of triglycerides (TG), high density lipoprotein cholesterol (HDL-C), uric acid (UA) as well as blood pressure (BP) in non-diabetic subjects with fasting plasma glucose <6.1 mmol/l. Parallel analyses were conducted in all subjects in the database (n=1093) and in those with all variables available (n=309). In the univariate analysis both FPI and M were significantly correlated with TG, HDL-C, UA and BP (systolic, diastolic and mean). Multivariate regression analyses including center, sex, age, body mass index (BMI), FPI and M as independent variables showed that: (1) TG and UA were positively correlated with FPI and negatively correlated with M; (2) HDL-C was negatively correlated with FPI and positively correlated with M; and (3) BP was negatively correlated with both FPI and M. Analyses of covariance showed that, after adjusting for center, sex, age and BMI, subjects with isolated hyperinsulinemia or isolated insulin resistance had higher TG and UA and lower HDL-C. Subjects with isolated insulin resistance had also higher BP whereas subjects with isolated hyperinsulinemia had lower BP. Subjects with both defects had a worse profile., Conclusions: Hyperinsulinemia and insulin resistance might contribute with distinct and independent mechanisms to the development of several metabolic and hemodynamic disorders often clustering in the same individual. In particular, hypertriglyceridemia, low HDL-cholesterol and hyperuricemia seem to be related to both hyperinsulinemia and insulin resistance, whereas hypertension seems to be related only to insulin resistance.

Objectives: Left ventricular (LV) diastolic dysfunction is considered the earliest manifestation of diabetic cardiomyopathy. Whether LV abnormalities identified at rest by echocardiography predict peak exercise LV performance in uncomplicated type 1 diabetes mellitus (DM1) is largely unknown., Research Design and Methods: We evaluated LV size, mass, and functions and peak exercise LV performance in 25 subjects with uncomplicated DM1 (median disease duration 13.5 years, 1-30 years) and in 56 non-DM subjects (24 hypertensive (HT) and 32 normotensive (NT)). Overt coronary heart disease, significant microangiopathy and central autonomic neuropathy were minimized by exclusion criteria. Peak exercise LV stroke index (SVi), cardiac index (COi), LV ejection fraction (EF), LV end-diastolic and end-systolic volumes were assessed noninvasively. No subject was on cardiovascular medications at the time of evaluation., Results: In our study, DM1 did not show LV hypertrophy or impaired LV systolic function at rest. Prevalence of diastolic dysfunction was 8% among DM1, 18% among NT and 50% among HT. Pre-exercise heart rate, SVi, COi, and peak exercise blood pressure (BP) and heart rate were comparable among the three groups, but peak exercise LV EF, SVi and COi were lower in DM1 than in HT and NT independent to covariates (p<0.05). In separate analyses, DM1 predicted lower peak exercise SVi (B=-6.2) and COi (B=-1.6, both p<0.05) independently. Within DM1, glycated haemoglobin (HbA1c) and disease duration did not predict peak exercise LV systolic function., Conclusions: Our study suggests that uncomplicated DM1 may be associated with subnormal LV contractility reserve, which might not be predicted by LV dysfunction evaluated at rest.

Purpose of Review: The aim of this article is to evaluate food properties able to influence specific physiological targets that may be helpful for the prevention and management of overweight and diabetes., Recent Findings: Observational and intervention studies have clearly shown that type 2 diabetes can be prevented by lifestyle measures, including reduced energy intake to induce a modest but sustained weight reduction, together with changes in diet composition., Summary: Foods can be regarded as functional if proven to affect beneficially one or more target functions in the body, beyond adequate nutritional effects, in a way relevant to improved state of health and well-being, reduction of risk of diseases, or both. Functional foods might have a particularly high impact for prevention or treatment of overweight and diabetes for which, more than in many other fields, the link between nutrition, biological responses and diseases is clearly established. Functional foods for obesity should be able to influence the energy balance equation regulated by the control of energy intake or of energy dissipated as heat (thermogenesis). For prevention of type 2 diabetes, several unmodified foods with functional properties have already been identified (low saturated fat products, vegetables, fruit, wholegrain foods, low glycemic index starchy foods). Overall, the available evidence on functional foods so far identified in this field is incomplete: the major gap is the lack of diet-based intervention trials of sufficient duration to be relevant for the natural history of diseases like overweight and diabetes.

Objective: There is some evidence that acute hyperglycemia (H) may cause vascular dysfunction in normal subjects. This study investigates whether acute, short-term H affects coronary vasodilatory function in healthy subjects., Design: Diastolic peak flow velocity in the left anterior descending coronary artery was measured at rest and after dipyridamole (0.56 mg/kg over 4 min) using transthoracic color Doppler echocardiography in 13 healthy men. Coronary flow reserve (CFR) was defined as the ratio of dipyridamole-induced coronary peak diastolic to resting peak diastolic flow velocity. CFR was measured both in euglycemia (E) and after 3 h H ( approximately 14 mmol/liter) by a variable infusion of glucose and octreotide (0.4 mg/h) to prevent increase in insulin concentration., Results: Fasting plasma glucose increased to 14.3 +/- 0.33 mmol/liter during the study and maintained variability within less than 10%. Plasma insulin remained nearly stable during H. Resting diastolic flow velocity was 18.5 +/- 0.6 cm/sec in E and increased to 20.0 +/- 0.7 cm/sec during H (P < 0.005). Dipyridamole infusion produced a marked increase in coronary flow velocity, which reached values of 50.8 +/- 2.9 cm/sec in E and 51.8 +/- 2.1 cm/sec in H (P = not significant). CFR was 2.78 +/- 0.16 in E and 2.59 +/- 0.12 in H (P = not significant)., Conclusion: Our study indicates that short-term hyperglycemia does not affect the vasodilatory response of coronary microcirculation in healthy subjects.

Objective: The aim of this study was to test whether vascular reactivity is modified by improving metabolic control and peripheral insulin resistance in type 2 diabetes., Research Design and Methods: In a randomized, double-blind design, we assigned 74 type 2 diabetic patients to rosiglitazone (8 mg/day), metformin (1,500 mg/day), or placebo treatment for 16 weeks and measured insulin sensitivity (euglycemic insulin clamp), ambulatory blood pressure, and forearm blood flow response to 1) intra-arterial acetylcholine (ACh), 2) intra-arterial nitroprusside, 3) the clamp, and 4) blockade of nitric oxide (NO) synthase., Results: Compared with 25 nondiabetic subjects, patients had reduced insulin sensitivity (30 +/- 1 vs. 41 +/- 3 micromol. min(-1). kg fat-free mass(-1); P < 0.001) and reduced maximal response to ACh (586 +/- 42 vs. 883 +/- 81%; P < 0.001). Relative to placebo, 16 weeks of rosiglitazone and metformin similarly reduced fasting glucose (-2.3 +/- 0.5 and -2.3 +/- 0.5 mmol/l) and HbA(1c) (-1.2 +/- 0.3 and -1.6 +/- 0.3%). Insulin sensitivity increased with rosiglitazone (+6 +/- 3 micromol. min(-1). kg fat-free mass(-1); P < 0.01) but not with metformin or placebo. Ambulatory diastolic blood pressure fell consistently (-2 +/- 1 mmHg; P < 0.05) only in the rosiglitazone group. Nitroprusside dose response, clamp-induced vasodilatation, and NO blockade were not affected by either treatment. In contrast, the slope of the ACh dose response improved with rosiglitazone (+40% versus baseline, P < 0.05, +70% versus placebo, P < 0.005) but did not change with either metformin or placebo. This improvement in endothelium-dependent vasodilatation was accompanied by decrements in circulating levels of free fatty acids and tumor necrosis factor-alpha., Conclusions: At equivalent glycemic control, rosiglitazone, but not metformin, improves endothelium dependent vasodilatation and insulin sensitivity in type 2 diabetes.

Muscle sympathetic nerve activity was measured in nine acromegalic patients (age, 35 +/- 4 yr; body mass index, 28 +/- 2 kg/m2) and eight healthy subjects (age, 32 +/- 3 yr; body mass index, 25 +/- 2 kg/m2) by combining the forearm arterial-venous difference technique with the tracer method [infusion of tritiated norepinephrine (NE)]. Muscle NE release was quantified both at rest and during physiological hyperinsulinemia while maintaining euglycemia (approximately 90 mg/dL) by means of the euglycemic clamp. Arterial plasma NE was similar in the two groups at rest (197 +/- 28 and 200 +/- 27 pg/mL (-1) and slightly increased during insulin infusion. Forearm NE release was 2.33 +/- 0.55 ng x liter(-1) x min(-1) in healthy subjects and 2.67 +/- 0.61 ng x liter(-1) x min(-1) in acromegalic subjects in the basal state and increased to a similar extent during insulin infusion in both groups (3.13 +/- 0.71 and 3.32 +/- 0.75 ng x L(-1) x min(-1), P < 0.05 vs. basal), indicating a normal stimulatory effect of insulin on muscle sympathetic activity. In contrast, insulin-stimulated forearm glucose uptake was markedly lower in acromegalic patients (2.3 +/- 0.4 mg x L(-1) x min(-1)) than in control subjects (7.9 +/- 1.3 mg x L(-1) x min(-1), P < 0.001), indicating the presence of severe insulin resistance involving glucose metabolism. Our data demonstrate that patients with long-term acromegaly have normal sympathetic activity in the skeletal muscle in the basal, postabsorptive state and normal increments in NE spillover in response to the sympatho-excitatory effect of insulin. Thus, the presence of severe insulin resistance in acromegaly is not accounted for by adrenergic mechanisms.

In population surveys, blood pressure and plasma insulin concentration are related variables, but the association is confounded by age and obesity. Whether insulin resistance is independently associated with higher blood pressure in normal subjects is debated. We analyzed the database of the European Group for the Study of Insulin Resistance, made up of nondiabetic men and women from 20 centers, in whom insulin sensitivity was measured by the euglycemic insulin clamp. After excluding subjects aged > or =70 years, those with severe obesity (body mass index [BMI] >40 kg x m[-2]), and those with abnormal blood pressure values (> or =140/90 mm Hg), 333 cases (ages 18 to 70 years; BMI, 18.4 to 39.8 kg x m[-2]) were available for analysis. In univariate analysis, both systolic and diastolic blood pressures were inversely related to insulin sensitivity, with r values of 0.18 (P<.005) and 0.34 (P<.0001), respectively. In a multivariate model simultaneously accounting for sex, age, BMI, and fasting insulin, systolic and diastolic blood pressures were still inversely related to insulin sensitivity (partial r, 0.15 and 0.19; P<.01 for both). In this model, age was positively related to blood pressure levels independently of insulin sensitivity, whereas BMI was not. The predicted impact on blood pressure of a decrease in insulin sensitivity of 10 micromol x min(-1) x kg(-1) was +1.4 mm Hg, similar to that associated with a 10-year difference in age. Although insulin levels and insulin action were reciprocally interrelated, diastolic blood pressure varied as a simultaneous function of both. In normotensive, nondiabetic Europeans, insulin sensitivity and age are significant, mutually independent correlates of blood pressure, whereas body mass is not. The relation of blood pressure to both insulin action and circulating insulin levels is compatible with distinct influences on blood pressure by insulin resistance and compensatory hyperinsulinemia.

Very little is known about the atherosclerotic risk in patients with childhood-onset growth hormone deficiency (GHD). Such data may be relevant to reconstructing the natural course of the cardiovascular abnormalities associated with GHD. To this end, the intima-media thickness (IMT) of the carotid arteries and the vascular risk factors were evaluated in 14 childhood-onset GHD patients (age 25 +/- 1 yr, BMI 22 +/- 0.6 Kg/m2) and in 14 age-, sex-, and BMI-matched control subjects. IMT was greater in GHD patients (0.83 +/- 0.06 and 0.81 +/- 0.06 mmol/L for the right and left carotid artery) than in controls (0.64 +/- 0.03 and 0.64 +/- 0.04 mmol/L, P < 0.01 and P < 0.02, respectively). Serum total and lipoprotein cholesterol, and serum total triglycerides did not differ between the two groups. However, a significant increase in low density lipid triglycerides was present in GHD patients (0.27 +/- 0.02 mmol/L) compared with controls (0.19 +/- 0.01; P = 0.007). No difference was found in plasma fibrinogen and serum Lp(a) levels. Plasma glucose and insulin concentrations were similar in GHD and control subjects both in the fasted state and after an oral glucose load. In conclusion, young patients with childhood-onset GHD show an increased IMT in the absence of clear-cut abnormalities of the classic vascular risk factors. This suggests a role for GH deficiency per se in increasing the atherosclerotic risk.

The deoxyglucose method for calculation of regional cerebral glucose metabolism by PET using 18F-2-fluoro-2-deoxy-d-glucose (FDG) requires knowledge of the lumped constant, which corrects for differences in the blood-brain barrier (BBB) transport and phosphorylation of FDG and glucose. The BBB transport rates of FDG and glucose have not previously been determined in humans. In the present study these transport rates were measured with the intravenous double-indicator method in 24 healthy subjects during normoglycemia (5.2 +/- 0.7 mM). Nine subjects were restudied during moderate hypoglycemia (3.4 +/- 0.4 mM) and five subjects were studied once during hyperglycemia (15.0 +/- 0.7 mM). The global ratio between the unidirectional clearances of FDG and glucose (K1*/K1) was similar in normoglycemia (1.48 +/- 0.22), moderate hypoglycemia (1.41 +/- 0.23), and hyperglycemia (1.44 +/- 0.20). This ratio is comparable to what has been obtained in rats. We argue that the global ratio is constant throughout the brain and may be applied for the regional determination of LC. We also determined the transport parameters of the two hexoses from brain back to blood and, assuming symmetrical transport across the BBB, we found evidence of a larger initial distribution volume of FDG in brain (0.329 +/- 0.236) as compared with that of glucose (0.162 +/- 0.098, p < 0.005). The difference can be explained by the very short experimental time, in which FDG may distribute both intra- and extracellularly, whereas glucose remains in a volume comparable to the interstitial fluid of the brain.

Background: Cardiac hypertrophy is a physiologic response that allows the heart to adapt to an excess hemodynamic load. We hypothesized that inducing cardiac hypertrophy with recombinant human growth hormone might be an effective approach to the treatment of idiopathic dilated cardiomyopathy, a condition in which compensatory cardiac hypertrophy is believed to be deficient., Methods: Seven patients with idiopathic dilated cardiomyopathy and moderate-to-severe heart failure were studied at base line, after three months of therapy with human growth hormone, and three months after the discontinuation of growth hormone. Standard therapy for heart failure was continued throughout the study. Cardiac function was evaluated with Doppler echocardiography, right-heart catheterization, and exercise testing., Results: When administered at a dose of 14 IU per week, growth hormone doubled the serum concentrations of insulin-like growth factor I. Growth hormone increased left-ventricular-wall thickness and reduced chamber size significantly. Consequently, end-systolic wall stress (a function of both wall thickness and chamber size) fell markedly (from a mean [+/-SE] of 144+/-11 to 85+/-8 dyn per square centimeter, P<0.001). Growth hormone improved cardiac output, particularly during exercise (from 7.4+/-0.7 to 9.7+/-0.9 liters per minute, P=0.003), and enhanced ventricular work, despite reductions in myocardial oxygen consumption (from 56+/-6 to 39+/-5 ml per minute, P=0.005) and energy production (from 1014+/-100 to 701+/-80 J per minute, P=0.002). Thus, ventricular mechanical efficiency rose from 9+/-2 to 21+/-5 percent (P=0.006). Growth hormone also improved clinical symptoms, exercise capacity, and the patients' quality of life. The changes in cardiac size and shape, systolic function, and exercise tolerance were partially reversed three months after growth hormone was discontinued., Conclusions: Recombinant human growth hormone administered for three months to patients with idiopathic dilated cardiomyopathy increased myocardial mass and reduced the size of the left ventricular chamber, resulting in improvement in hemodynamics, myocardial energy metabolism, and clinical status.

To determine whether the anti-insulin effect of epinephrine is due to a direct antagonism on target tissues or is mediated by indirect mechanisms (systemic substrate and/or hormone changes), insulin and epinephrine were infused intrabrachially in five normal volunteers using the forearm perfusion technique. Insulin (2.5 mU/min) was infused alone for 90 minutes and in combination with epinephrine (25 ng/min) for an additional 90 minutes, so as to increase the local concentrations of these hormones to physiological levels (60 to 75 microU/mL and 200 to 250 pg/mL for insulin and epinephrine, respectively). Systemic plasma glucose and free fatty acids (FFA) concentrations remained stable at their basal values during local hormone infusion. Forearm glucose uptake (FGU) increased in response to insulin alone from 0.8 +/- 0.2 mg.L-1.min-1 to 4.3 +/- 0.8. Addition of epinephrine completely abolished the insulin effect on FGU, which returned to its preinfusion value (0.7 +/- 0.2). Forearm lactate release was slightly increased by insulin alone, but rose markedly on addition of epinephrine (from 5.2 +/- 0.8 mumol.L-1.min-1 to 17 +/- 2; P less than .02). During infusion of insulin alone, forearm FFA release (FFR) decreased significantly from the postabsorptive value of 1.76 +/- 0.25 mumol.L-1.min-1 to 1.05 +/- 0.11 (P less than .01). Epinephrine addition reverted insulin suppression of FFR, which returned to values slightly above baseline (2.06 +/- 0.47 mumol.L-1.min-1; P less than .05 v insulin alone). The data demonstrate that epinephrine is able to antagonize directly insulin action on forearm tissues with respect to both stimulation of glucose uptake and inhibition of FFA mobilization.

To investigate the effects of carnitine on insulin sensitivity in non-insulin-dependent diabetes, insulin-mediated glucose disposal was measured in nine diabetic patients (age 54 +/- 3 years, BMI 27 +/- 1 kg/mq) during a primed (3 mmol) constant (1.7 mumol/min) intravenous infusion of carnitine. In control experiments, the same patients received saline instead of carnitine. Plasma glucose concentration was maintained constant at the level of 100 mg/dl during both studies while plasma insulin was raised to a plateau of 60 microU/ml. Despite similar insulin levels, whole-body glucose utilization was higher with carnitine (4.05 +/- 0.37 mg/kg/min) than saline infusion (3.52 +/- 0.36). Blood lactate concentrations were similar in the basal state and decreased significantly during carnitine infusion (P less than 0.05-0.005), whereas it remained substantially unchanged during saline infusion. Plasma FFA decreased to a similar level (0.1 mmol/l) in both studies. We conclude that an acute carnitine administration is able to improve insulin sensitivity in NIDDM patients. The lactate data suggest that this effect may at least in part be mediated by carnitine activation of pyruvate dehydrogenase.

Eight male non-insulin-dependent diabetic patients participated in a double-blind randomized cross-over study (2 weeks for each period) evaluating the effects of 10 g/day fish oil dietary supplementation on glucose and lipid metabolism. Fasting serum triglyceride concentrations were decreased by fish oil because of a reduction in VLDL (1.4 +/- 0.2 vs. 1.9 +/- 0.2 mmol/l, P less than 0.025). LDL cholesterol concentration was instead increased (3.4 +/- 0.3 vs. 2.8 +/- 0.3 mmol/l, P less than 0.025) and net changes in VLDL triglyceride and in LDL cholesterol were inversely correlated (r = -0.86, P less than 0.01). Plasma free fatty acids concentrations and turnover rate [( 3H]palmitate method) were similar after fish oil and placebo. Fish oil supplement did not induce significant changes in fasting blood glucose (8.1 +/- 1.1 vs. 8.5 +/- 1.2 mmol/l) and average daily blood glucose (BG) (9.4 +/- 3.2 vs. 9.3 +/- 3.5 mmol/l). Glucose stimulated plasma insulin response during a hyperglycemic clamp was not significantly influenced by fish oil both in the early phase and during steady state. Insulin sensitivity (M/I index) was also unchanged. In conclusion, this study shows that a dietary supplement of fish oil decreases plasma triglyceride levels in non-insulin-dependent diabetic patients, an increased conversion rate of VLDL to LDL playing a role in this change. With this dosage of fish oil no relevant variations in glycemic control, insulin secretion and insulin sensitivity occurred.

To determine the contribution of skeletal muscle to fasting hyperglycemia in noninsulin dependent type II diabetes (NIDDM), the forearm balance of glucose, lactate, and alanine was quantified in 25 control subjects, 21 hyperglycemic (blood glucose: 11.6 mmol/L), and 19 insulin-treated patients with NIDDM (blood glucose: 5.8 mmol/L). Forearm glucose uptake was similar in controls (4.6 +/- 0.6 mumol L-1 min-1) and in hyperglycemic diabetic patients (4.5 +/- 0.9 mumol L-1 min-1). In spite of this, in the diabetic patients lactate (5.1 +/- 0.8 mumol L-1 min-1) and alanine (2.6 +/- 0.4) release by the forearm was 3- and 2-fold higher than in the control group (lactate: 1.7 +/- 0.8, P less than 0.005; and alanine: 1.3 +/- 0.2, P less than 0.05, respectively). The ratio of lactate release to glucose uptake was 57% and 18% in diabetic and control subjects, respectively. Insulin administration did not affect either glucose uptake or the release of gluconeogenic substrates by the forearm. It is concluded that: 1) in fasting patients with NIDDM, glucose is taken up by the skeletal muscle in normal amounts but preferentially used nonoxidatively with lactate formation. This suggests that, although the muscle does not contribute directly to fasting hyperglycemia, it may play an indirect role through an increased delivery of glucose precursors; and 2) insulin-induced normoglycemia is maintained by mechanisms that do not involve the exchange of glucose and gluconeogenic substrates by the skeletal muscle.

To evaluate the contribution of the splanchnic area to the carbohydrate abnormalities associated with chronic uremia, the splanchnic exchange of glucose and gluconeogenic substrates was quantitated basally and after an iv glucose load in nine uremic patients with impaired glucose tolerance and seven control subjects. In the basal state, blood glucose and splanchnic glucose production were similar in the two groups. During glucose infusion (33 mumol/kg.min for 90 min), blood glucose reached significantly higher levels in the uremic patients than in controls (P less than 0.02). Plasma insulin increased slightly more in uremic patients than in controls (P less than 0.05 at 15 min). Both basal and postglucose glucagon levels were 2- to 3-fold higher in uremic patients than in normal subjects (P less than 0.05-0.02). In both groups, splanchnic glucose balance switched from net output in the basal state (-9.4 +/- 0.5 and -8.0 +/- 1.1 mumol/kg.min in normals and uremics, respectively) to net uptake with glucose infusion. However, this response was less marked in the uremic patients than in normal subjects (P less than 0.05-0.02 at 30 and 90 min). The cumulative net splanchnic glucose balance over the 90-min study period was 538 +/- 55 mumol/kg in normal subjects and 279 +/- 89 in uremic subjects (P less than 0.05). A net splanchnic lactate uptake was present in the basal state in normal (4.2 +/- 0.5 mumol/kg.min) and uremic subjects (3.4 +/- 0.5). During glucose infusion, in normal subjects splanchnic lactate exchange switched to a net output (-4.0 +/- 1.6 mumol/kg.min), whereas in the uremic group it remained as a net uptake (1.1 +/- 0.7) throughout the study period. Splanchnic gluconeogenic amino acid uptake was similar in the two groups in the basal state (1.8 +/- 0.1 mumol/kg.min and 2.2 +/- 0.2 in normal and uremic subjects, respectively). Glucose infusion caused a marked fall in amino acid uptake by liver in normal subjects, whereas no change was observed in the uremic group (0.9 +/- 0.3 and 1.9 +/- 0.2 mumol/kg.min, respectively). Splanchnic glycerol uptake was not different in the two groups in the basal state (0.75 +/- 0.2 and 1.1 +/- 0.2 mumol/kg.min) and decreased to a similar extent during glucose infusion. We conclude the following. 1) In uremic patients with glucose intolerance but normal fasting glycemia, the splanchnic metabolism of glucose and gluconeogenic substrates is normal in the postabsorptive state.(ABSTRACT TRUNCATED AT 400 WORDS)

This study was designed to quantitate glucose and FFA disposal by muscle tissue in patients with type II diabetes and to investigate the relationship between FFA metabolism and insulin resistance. The forearm perfusion technique was used in six normal subjects and two groups of normal weight diabetic patients, i.e. untreated (n = 8) and insulin-treated (n = 6). The latter received 2 weeks of intensive insulin therapy before the study. Plasma insulin levels were raised acutely [950-1110 pmol/L) (130-150 microU/mL)], while the blood glucose concentration was clamped at its basal value [4.9 +/- 0.1 (+/- SE) mmol/L in the normal subjects, 5.7 +/- 0.5 in the insulin-treated diabetic patients, and 5.5 +/- 0.3 in the untreated diabetic patients] by a variable glucose infusion. During the control period, arterial FFA concentrations were similar in the three groups, and they decreased to a comparable extent (less than 0.1 mmol/L) in response to insulin infusion. During the control period, the mean forearm FFA uptake was 2.5 +/- 0.5 mumol/L.min in the normal subjects, 2.9 +/- 0.5 in the insulin-treated patients, and 2.1 +/- 0.5 in the untreated diabetic patients. During the insulin infusion, FFA uptake was profoundly suppressed to similar levels in the normal subjects (0.9 +/- 0.1 mumol/L.min), the insulin-treated diabetic patients (1.1 +/- 0.3), and the untreated diabetic patients (0.9 +/- 0.1; P less than 0.001). Forearm glucose uptake was similar in the three groups during the control period. It increased during the insulin infusion, but the response in both diabetic groups was less than that in the normal subjects. The total amounts of glucose taken up by the forearm during the study period were 5.2 +/- 0.7, 2.6 +/- 0.5, and 2.1 +/- 0.6 mmol/L.min in the normal subjects, the insulin-treated diabetic patients, and the untreated diabetic patients, respectively (P less than 0.01). We conclude that 1) insulin-mediated glucose uptake by forearm skeletal muscle is markedly impaired in type II diabetes and improves only marginally after 2 weeks of intensive insulin therapy; 2) in contrast, no appreciable abnormality in forearm FFA metabolism is demonstrable in insulin-treated type II diabetic patients; and 3) FFA do not contribute to the insulin-treated skeletal muscle insulin resistance that occurs in patients with type II diabetes mellitus.

Sixty-four unrelated healthy subjects were studied for the detection of a DNA polymorphism at the 5' end of the insulin gene. No significant difference between the groups was found in blood glucose values at fasting and after an oral glucose load. A significant association was found between fasting (P less than 0.05) and after load plasma C-peptide levels (P less than 0.01) and the presence of a 1.6 Kb insertion at the 5' end of the insulin gene. A gene dose-dependent effect was noted, class 3/3 individuals having the lowest after-load C-peptide concentration and class 1/3 an intermediate level (F for the linear trend: P = 0.007). This might suggest that insulin gene polymorphism affects insulin secretion in healthy individuals. In order to confirm this, a subgroup of six class 3/3 and eight class 1/1 individuals subsequently underwent a hyperglycaemic clamp. The tissue sensitivity to insulin was similar in the two groups but glucose-stimulated insulin secretion was markedly impaired in homozygotes for the class 3 allele. In this group, insulin secretion was, on average, only one-third of that in class 1/1 individuals (P less than 0.02). Similarly impaired in class 3/3 persons was the glucose + arginine-stimulated insulin secretion (P less than 0.05). We conclude that the polymorphism at the 5' end of the insulin gene is associated with variations in insulin secretion in healthy humans.

Blood intermediary metabolite and hormone concentrations have been assessed in 10 insulin-dependent diabetic patients on SC injection therapy and during 24 hr of relative normoglycaemia on an artificial pancreas (GCIIS). Mean blood lactate (0.96 +/- 0.07 mmol/l) and pyruvate (0.087 +/- 0.004 mmol/l) levels remained elevated compared to normal controls (0.76 +/- 0.04 and 0.064 +/- 0.003, p less than 0.05 and less than 0.001, respectively). No tendency was detected for these levels to regress towards normal over the 24 hr period on the GCIIS. Mean individual 24 hr blood lactate concentrations correlated significantly with mean free insulin levels (r = 0.85, p less than 0.002), but inversely with prior out-patient diabetic control (r = 0.64, p less than 0.05). The shape of the 24 hr profiles of blood lactate and pyruvate changed between SC therapy and the GCIIS, corresponding in both studies to the form of the free insulin profile. Blood alanine and glycerol profiles were not abnormal on either regime. Blood 3-hydroxybutyrate levels were abnormal on both SC therapy (0.16 1.14 mmol/l) and the GCIIS (0.15 1.20 mmol/l, controls 0.04 1.31 mmol/l), with concentrations on SC therapy correlating positively with previous control. Abnormalities of intermediary metabolite levels persist during feedback normalization of blood glucose levels, with evidence of influences from both prior diabetic control, and current insulin delivery.

Twenty-four hour plasma free insulin and blood glucose and intermediary metabolite profiles have been measured in 6 C-peptide deficient 'brittle' diabetic patients, during continuous sc and im insulin infusion. During sc infusion free insulin profiles were erratic and unpredictable. Mean 24 h blood glucose levels were raised at 12.6 +/- 2.1 (SE) mmol/l, and 3-hydroxybutyrate at 0.24 +/- 0.08 mmol/l. Blood lactate (1.88 +/- 0.18 mmol/l) and glycerol (0.084 +/- 0.007) were also elevated. Insulin (im) restored free insulin profiles to the normal pattern as found in 'stable' diabetics on sc infusion, with characteristic post-meal peaks (49 +/- 7, 103 +/- 35, and 95 +/- 34 mU/l) and stable night-time levels. Mean 24 h blood glucose was 6.7 +/- 1.1 mmol/l (P less than 0-.05 compared to sc infusion) and 3-hydroxybutyrate 0.07 +/- 0.02 mmol/l (P less than 0.05). Blood lactate (1.67 +/- 0.08 mmol/l) and glycerol (0.10 +/- 0.02 mmol/l) levels remained abnormal. The ratio of plasma free insulin to insulin dose administered was significantly higher during im infusion. In the 6 'stable' diabetics on sc insulin infusion good blood glucose control (7.1 +/- 0.9 mmol/l) was accompanied by clear post-prandial insulin peaks, and stable nocturnal levels. The results strongly suggest that in one category of 'brittle' diabetics there is defective and erratic sc insulin absorption.

The effects of beta-blockers on glucose tolerance, insulin secretion and peripheral insulin sensitivity were evaluated by oral glucose tolerance test and euglycaemic insulin technique in six normoglycaemic patients with primary arterial hypertension at the end of 3-week treatments with placebo (one tablet twice daily) and propranolol (80 mg twice daily). Body weight did not change during the study (83 kg at the end of placebo, 83 kg at the end of propranolol), while blood pressure (150 +/- 9/97 +/- 8 mmHg on placebo, 138 +/- 8/89 +/- 8 mmHg on propranolol, P < 0.01) and heart rate (66 +/- 9 beats/min on placebo, 60 +/- 5 beats/min on propranolol, P < 0.05) showed a significant fall on the beta-blocker. No change was observed in glucose tolerance (incremental area for glucose 3462 +/- 1149 mg/dl per min on placebo, 3209 +/- 1695 mg/dl per min on propranolol), insulin secretion (incremental area for serum insulin 7579 +/- 4380 microU/ml per min on placebo, 7934 +/- 4351 microU/ml per min on propranolol) and peripheral insulin sensitivity (metabolic clearance rate 11 +/- 4 ml/kg per min on placebo, 13 +/- 6 ml/kg per min on propranolol). These data support the hypothesis that chronic treatment with adrenergic blocking agents does not induce any significant change in insulin secretion or peripheral insulin sensitivity.

In order to evaluate the influence of serum insulin levels on serum lipoprotein composition, 62 randomly selected healthy males were studied. All of them had a normal glucose tolerance. The Insulin Response to a bolus of intravenous glucose (0.50 g/kg) was significantly correlated with VLDL-Triglyceride (p less than 0.01), VLDL-Cholesterol (p less than 0.01) and with the "Atherogenic Index" (Formula: see text) (p less than 0.01). Moreover, stratifing the all population in quartiles according to the Insulin Response distribution, the highest quartile had a significant increase in Total and VLDL-Cholesterol levels (p less than 0.02), as well as in Total (p less than 0.02), VLDL (p less than 0.02) and LDL (p less than 0.01) Triglyceride, in comparison with the lowest quartile. The Atherogenic Index was also significantly elevated in the high Insulin Response group (p less than 0.005). The influence of serum insulin on lipoprotein metabolism was also evaluated by a stepwise multiple regression analysis. Body weight, Insulin Response and Exogenous Triglyceride removal were independently correlated with VLDL-Triglyceride concentration (r = 0.58, p less than 0.001). VLDL cholesterol concentration and fasting serum insulin levels were inversely correlated with HDL-Cholesterol (r = 0.49, p less than 0.001). In conclusion, in absence of any metabolic derangement, high insulin levels are associated with multiple lipoprotein abnormalities. Insulin might act as a risk factor for arterial disease through its influence on serum lipoproteins.

This study attempts to evaluate whether the putative excess risk of cardiovascular disease in individuals with impaired glucose tolerance (IGT) can be explained by the clustering of other major cardiovascular risk factors after controlling for obesity. The study population was 1376 male and female employees of a Naples telephone company who had participated in a health survey in which an oral glucose tolerance test (OGTT) was given. After excluding treated hypertensives, we recruited all 65 individuals with IGT and 125 euglycemic controls matched for gender, age, and weight. Systolic and diastolic blood pressure was significantly higher in individuals with IGT (134 +/- 16 vs 127 +/- 15 mm Hg, p less than 0.001; 87 +/- 10 vs 84 +/- 8 mm Hg, p less than 0.05 (M +/- SD). Blood lipids were similar in the two groups (total cholesterol was 214 +/- 34 vs 218 +/- 40 mg/dl; HDL cholesterol was 39 +/- 9 vs 40 +/- 10 mg/dl; total triglyceride was 145 +/- 58 vs 135 +/- 63 mg/dl). Serum insulin values (fasting or at 1 or 2 hours after 75 g of oral glucose) were also similar. The number of persons currently smoking was significantly lower among individuals with IGT (30% vs 47%, p less than 0.025) but the percentage of exsmokers was identical in the two groups. We conclude that, among the possible cardiovascular risk factors investigated, blood pressure is the only one significantly associated with IGT independent of matched variables and antihypertensive treatment.