ABSTRACT
BACKGROUND: There is increasing evidence to suggest that not all individuals with type 2 diabetes mellitus (T2DM) have equal risk for developing cardiovascular disease. We sought to compare the yield of testing for pre-clinical atherosclerosis with various approaches. METHODS: 98 asymptomatic individuals with T2DM without known coronary artery disease (CAD) were enrolled in a prospective study and underwent carotid ultrasound, exercise treadmill testing (ETT), coronary artery calcium (CAC) scoring, and coronary computed tomography angiography (CTA). RESULTS: Of 98 subjects (average age 55 ± 6, 64 % female), 43 (44 %) had coronary plaque detectable on CTA, and 38 (39 %) had CAC score >0. By CTA, 16 (16 %) had coronary stenosis ≥50 %, including three subjects with CAC = 0. Subjects with coronary plaque had greater prevalence of carotid plaque (58 % vs. 38 %, p = 0.01) and greater carotid intima media thickness (0.80 ± 0.20 mm vs. 0.70 ± 0.11 mm, p = 0.02). Notably, 18 of 55 subjects (33 %) with normal CTA had carotid plaque. Eight subjects had a positive ETT, of whom five had ≥ 50 % coronary stenosis, two had <50 % stenosis, and one had no CAD. Among these tests, CAC scoring had the highest sensitivity and specificity for prediction of CAD. CONCLUSION: Among asymptomatic subjects with T2DM, a majority (56 %) had no CAD by CTA. When compared to CTA, CAC was the most accurate screening modality for detection of CAD, while ETT and carotid ultrasound were less sensitive and specific. However, 33 % of subjects with normal coronary CTA had carotid plaque, suggesting that screening for carotid plaque might better characterize stroke risk in such patients.
Subject(s)
Carotid Artery Diseases/diagnostic imaging , Carotid Intima-Media Thickness , Coronary Angiography , Coronary Artery Disease/diagnostic imaging , Coronary Stenosis/diagnostic imaging , Diabetes Mellitus, Type 2/epidemiology , Diagnostic Imaging/methods , Mass Screening/methods , Tomography, X-Ray Computed , Vascular Calcification/diagnostic imaging , Adult , Aged , Asymptomatic Diseases , Brazil , Carotid Artery Diseases/epidemiology , Carotid Artery Diseases/physiopathology , Coronary Artery Disease/epidemiology , Coronary Artery Disease/physiopathology , Coronary Stenosis/epidemiology , Coronary Stenosis/physiopathology , Coronary Vessels/diagnostic imaging , Diabetes Mellitus, Type 2/diagnosis , Exercise Test , Female , Humans , Male , Middle Aged , Plaque, Atherosclerotic , Predictive Value of Tests , Prevalence , Prognosis , Prospective Studies , Reproducibility of Results , Vascular Calcification/epidemiology , Vascular Calcification/physiopathologyABSTRACT
BACKGROUND/AIMS: Berardinelli-Seip syndrome (BSS) is a recessive autosomal genetic disorder characterized by the near loss of adipose tissue with disturbance in lipid metabolism. METHODS: Biochemical and hormonal parameters and Pro12Ala, Pvull, Avall, Sstl and ADIPOQ polymorphisms in 22 patients with BSS were analyzed and examined for a possible association with lipid profiles. RESULTS: Parental consanguinity, insulin resistance and diabetes mellitus were observed in 63.6, 81.8 and 59.1% of patients, respectively. All individuals presented high triglyceride levels, and 68.1% of patients showed high cholesterol levels. The Pro/Pro genotype of the Pro12Ala polymorphism of the PPARγ2 gene was found in 86.3% of patients; the Ala/Ala variant was not observed in any patient. The PvuII polymorphism of the LPL gene showed a frequency of 50% for the P1P2 variant. The AvaII polymorphism of the LDLR gene showed a similar frequency of 40.9% for both CT and TT variants. The S1S1 genotype of the Sstl polymorphism of the APOC3 gene had a frequency of 86.3%. The CC allele of the ADIPOQ polymorphism of the adiponectin gene was found in 54.6% of patients. CONCLUSIONS: No association was found between lipid parameters and the relevant Pvull, Avall and Sstl polymorphisms. However, we did observe an association of the Pro12Ala and ADIPOQ polymorphisms with higher lipid levels, suggesting a close relationship between these factors.
Subject(s)
Adiponectin/genetics , Genetic Predisposition to Disease , Lipodystrophy, Congenital Generalized/genetics , PPAR gamma/genetics , Adult , Brazil , Cholesterol/blood , Female , Humans , Lipodystrophy, Congenital Generalized/blood , Male , Polymorphism, Single Nucleotide , Triglycerides/blood , White PeopleABSTRACT
BACKGROUND: Type 1 diabetes (T1DM) is frequently accompanied by dyslipidemia related with insulin-dependent steps of the intravascular lipoprotein metabolism. T1DM dyslipidemia may predispose to precocious cardiovascular disease and the lipid status in T1DM under intensive insulin treatment has not been sufficiently explored. The aim was to investigate the plasma lipids and the metabolism of LDL and HDL in insulin-treated T1DM patients with high glycemic levels. METHODS: Sixteen male patients with T1DM (26 ± 7 yrs) with glycated hemoglobin >7%, and 15 control subjects (28 ± 6 yrs) were injected with a lipid nanoemulsion (LDE) resembling LDL and labeled with (14)C-cholesteryl ester and (3)H-free-cholesterol for determination of fractional clearance rates (FCR, in h-1) and cholesterol esterification kinetics. Transfer of labeled lipids from LDE to HDL was assayed in vitro. RESULTS: LDL-cholesterol (83 ± 15 vs 100 ± 29 mg/dl, p=0.08) tended to be lower in T1DM than in controls; HDL-cholesterol and triglycerides were equal. LDE marker 14C-cholesteryl ester was removed faster from plasma in T1DM patients than in controls (FCR=0.059 ± 0.022 vs 0.039 ± 0.022h-1, p=0.019), which may account for their lower LDL-cholesterol levels. Cholesterol esterification kinetics and transfer of non-esterified and esterified cholesterol, phospholipids and triglycerides from LDE to HDL were also equal. CONCLUSION: T1DM patients under intensive insulin treatment but with poor glycemic control had lower LDL-cholesterol with higher LDE plasma clearance, indicating that LDL plasma removal was even more efficient than in controls. Furthermore, HDL-cholesterol and triglycerides, cholesterol esterification and transfer of lipids to HDL, an important step in reverse cholesterol transport, were all normal. Coexistence of high glycemia levels with normal intravascular lipid metabolism may be related to differences in exogenous insulin bioavailabity and different insulin mechanisms of action on glucose and lipids. Those findings may have important implications for prevention of macrovascular disease by intensive insulin treatment.
Subject(s)
Cholesterol, HDL/metabolism , Cholesterol, LDL/metabolism , Diabetes Mellitus, Type 1/drug therapy , Dyslipidemias/drug therapy , Insulin/therapeutic use , Triglycerides/metabolism , Adult , Blood Glucose/metabolism , Carbon Radioisotopes , Case-Control Studies , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/metabolism , Disease Management , Drug Administration Schedule , Dyslipidemias/complications , Dyslipidemias/metabolism , Fat Emulsions, Intravenous/administration & dosage , Fat Emulsions, Intravenous/metabolism , Glycated Hemoglobin/metabolism , Half-Life , Humans , Insulin/pharmacology , Lipid Metabolism/drug effects , MaleABSTRACT
BACKGROUND: The aim was to investigate new markers for type 2 diabetes (T2DM) dyslipidemia related with LDL and HDL metabolism. Removal from plasma of free and esterified cholesterol transported in LDL and the transfer of lipids to HDL are important aspects of the lipoprotein intravascular metabolism. The plasma kinetics (fractional clearance rate, FCR) and transfers of lipids to HDL were explored in T2DM patients and controls, using as tool a nanoemulsion that mimics LDL lipid structure (LDE). RESULTS: 14C- cholesteryl ester FCR of the nanoemulsion was greater in T2DM than in controls (0.07 ± 0.02 vs. 0.05 ± 0.01 h-1, p = 0.02) indicating that LDE was removed faster, but FCR 3 H- cholesterol was equal in both groups. Esterification rates of LDE free-cholesterol were equal. Cholesteryl ester and triglyceride transfer from LDE to HDL was greater in T2DM (4.2 ± 0.8 vs. 3.5 ± 0.7%, p = 0.03 and 6.8 ± 1.6% vs. 5.0 ± 1.1, p = 0.03, respectively). Phospholipid and free cholesterol transfers were not different. CONCLUSIONS: The kinetics of free and esterified cholesterol tended to be independent in T2DM patients and the lipid transfers to HDL were also disturbed. These novel findings may be related with pathophysiological mechanisms of diabetic macrovascular disease.
Subject(s)
Cholesterol Esters/metabolism , Cholesterol/metabolism , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/metabolism , Lipoproteins, HDL/blood , Lipoproteins, HDL/metabolism , Adult , Aged , Cholesterol/blood , Cholesterol Esters/blood , Female , Humans , Male , Middle AgedABSTRACT
There is a progressive deterioration in beta-cell function and mass in type 2 diabetics. It was found that islet function was about 50% of normal at the time of diagnosis, and a reduction in beta-cell mass of about 60% was shown at necropsy. The reduction of beta-cell mass is attributable to accelerated apoptosis. The major factors for progressive loss of beta-cell function and mass are glucotoxicity, lipotoxicity, proinflammatory cytokines, leptin, and islet cell amyloid. Impaired beta-cell function and possibly beta-cell mass appear to be reversible, particularly at early stages of the disease where the limiting threshold for reversibility of decreased beta-cell mass has probably not been passed. Among the interventions to preserve or "rejuvenate" beta-cells, short-term intensive insulin therapy of newly diagnosed type 2 diabetes will improve beta-cell function, usually leading to a temporary remission time. Another intervention is the induction of beta-cell "rest" by selective activation of ATP-sensitive K+ (K(ATP)) channels, using drugs such as diazoxide. A third type of intervention is the use of antiapoptotic drugs, such as the thiazolidinediones (TZDs), and incretin mimetics and enhancers, which have demonstrated significant clinical evidence of effects on human beta-cell function. The TZDs improve insulin secretory capacity, decrease beta-cell apoptosis, and reduce islet cell amyloid with maintenance of neogenesis. The TZDs have indirect effects on beta-cells by being insulin sensitizers. The direct effects are via peroxisome proliferator-activated receptor gamma activation in pancreatic islets, with TZDs consistently improving basal beta-cell function. These beneficial effects are sustained in some individuals with time. There are several trials on prevention of diabetes with TZDs. Incretin hormones, which are released from the gastrointestinal tract in response to nutrient ingestion to enhance glucose-dependent insulin secretion from the pancreas, aid the overall maintenance of glucose homeostasis through slowing of gastric emptying, inhibition of glucagon secretion, and control of body weight. From the two major incretins, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), only the first one or its mimetics or enhancers can be used for treatment because the diabetic beta-cell is resistant to GIP action. Because of the rapid inactivation of GLP-1 by dipeptidyl peptidase (DPP)-IV, several incretin analogs were developed: GLP-1 receptor agonists (incretin mimetics) exenatide (synthetic exendin-4) and liraglutide, by conjugation of GLP-1 to circulating albumin. The acute effect of GLP-1 and GLP-1 receptor agonists on beta-cells is stimulation of glucose-dependent insulin release, followed by enhancement of insulin biosynthesis and stimulation of insulin gene transcription. The chronic action is stimulating beta-cell proliferation, induction of islet neogenesis, and inhibition of beta-cell apoptosis, thus promoting expansion of beta-cell mass, as observed in rodent diabetes and in cultured beta-cells. Exenatide and liraglutide enhanced postprandial beta-cell function. The inhibition of the activity of the DPP-IV enzyme enhances endogenous GLP-1 action in vivo, mediated not only by GLP-1 but also by other mediators. In preclinical studies, oral active DPP-IV inhibitors (sitagliptin and vildagliptin) also promoted beta-cell proliferation, neogenesis, and inhibition of apoptosis in rodents. Meal tolerance tests showed improvement in postprandial beta-cell function. Obviously, it is difficult to estimate the protective effects of incretin mimetics and enhancers on beta-cells in humans, and there is no clinical evidence that these drugs really have protective effects on beta-cells.
Subject(s)
Diabetes Mellitus, Type 2/complications , Hypoglycemic Agents/therapeutic use , Insulin-Secreting Cells/pathology , Pancreatic Diseases/etiology , Pancreatic Diseases/prevention & control , Animals , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/physiopathology , Humans , Insulin-Secreting Cells/drug effects , Insulin-Secreting Cells/physiology , Models, Biological , Pancreatic Diseases/pathology , Pancreatic Diseases/physiopathology , Regeneration/drug effectsABSTRACT
CONTEXT: Congenital generalized lipodystrophy, or Berardinelli-Seip syndrome, is a rare autosomal recessive disease caused by mutations in either the BSCL2 or AGPAT2 genes. This syndrome is characterized by an almost complete loss of adipose tissue usually diagnosed at birth or early infancy resulting in apparent muscle hypertrophy. Common clinical features are acanthosis nigricans, hepatomegaly with or without splenomegaly and high stature. Acromegaloid features, cardiomyopathy and mental retardation can also be present. DESIGN: We investigated 11 kindreds from different geographical areas of Brazil (northeast and southeast). All coding regions as well as flanking intronic regions of both genes were examined. Polymerase chain reaction (PCR) amplifications were performed using primers described previously and PCR products were sequenced directly. RESULTS: Four AGPAT2 and two BSCL2 families harboured the same set of mutations. BSCL2 gene mutations were found in the homozygous form in four kindreds (c.412C>T c.464T>C, c.518-519insA, IVS5-2A>G), and in two kindreds compound mutations were found (c.1363C>T, c.424A>G). In the other four families, one mutation of the AGPAT2 gene was found (IVS3-1G>C and c.299G>A). CONCLUSIONS: We have demonstrated four novel mutations of the BSCL2 and AGPAT2 genes responsible for Berardinelli-Seip syndrome and Brunzell syndrome (AGPAT2-related syndrome).
Subject(s)
1-Acylglycerol-3-Phosphate O-Acyltransferase/genetics , GTP-Binding Protein gamma Subunits/genetics , Lipodystrophy, Congenital Generalized/genetics , Adolescent , Adult , Brazil , Child, Preschool , Consanguinity , Female , Humans , Infant , Male , Mutation , Pedigree , Point Mutation , Polymerase Chain ReactionABSTRACT
CONTEXT: Genetic polymorphisms at the perilipin (PLIN) locus have been investigated for their potential utility as markers for obesity and metabolic syndrome (MS). We examined in obese children and adolescents (OCA) aged 7-14 yr the association of single-nucleotide polymorphisms (SNP) at the PLIN locus with anthropometric, metabolic traits, and weight loss after 20-wk multidisciplinary behavioral and nutritional treatment without medication. DESIGN: A total of 234 OCA [body mass index (BMI = 30.4 +/- 4.4 kg/m(2); BMI Z-score = 2.31 +/- 0.4) were evaluated at baseline and after intervention. We genotyped four SNPs (PLIN1 6209T-->C, PLIN4 11482G-->A, PLIN5 13041A-->G, and PLIN6 14995A-->T). RESULTS: Allele frequencies were similar to other populations, PLIN1 and PLIN4 were in linkage disequilibrium (D' = 0.999; P < 0.001). At baseline, no anthropometric differences were observed, but minor allele A at PLIN4 was associated with higher triglycerides (111 +/- 49 vs. 94 +/- 42 mg/dl; P = 0.003), lower high-density lipoprotein cholesterol (40 +/- 9 vs. 44 +/- 10 mg/dl; P = 0.003) and higher homeostasis model assessment for insulin resistance (4.0 +/- 2.3 vs. 3.5 +/- 2.1; P = 0.015). Minor allele A at PLIN4 was associated with MS risk (age and sex adjusted) hazard ratio 2.4 (95% confidence interval = 1.1-4.9) for genotype GA and 3.5 (95% confidence interval = 1.2-9.9) for AA. After intervention, subjects carrying minor allele T at PLIN6 had increased weight loss (3.3 +/- 3.7 vs. 1.9 +/- 3.4 kg; P = 0.002) and increased loss of the BMI Z-score (0.23 +/- 0.18 vs. 0.18 +/- 0.15; P = 0.003). Due to group size, risk of by-chance findings cannot be excluded. CONCLUSION: The minor A allele at PLIN4 was associated with higher risk of MS at baseline, whereas the PLIN6 SNP was associated with better weight loss, suggesting that these polymorphisms may predict outcome strategies based on multidisciplinary treatment for OCA.
Subject(s)
Metabolic Syndrome/epidemiology , Metabolic Syndrome/genetics , Obesity/genetics , Phosphoproteins/genetics , Weight Loss/genetics , Adolescent , Alleles , Anthropometry , Blood Pressure/physiology , Body Mass Index , Brazil/epidemiology , Carrier Proteins , Child , Female , Gene Frequency , Genetic Variation , Glucose Tolerance Test , Humans , Insulin/blood , Male , Perilipin-1 , Polymorphism, Single Nucleotide , Waist CircumferenceABSTRACT
OBJECTIVE: Ischemic preconditioning is an increased tolerance to myocardial ischemia during the second of two consecutive exercise tests. ATP-sensitive K(+) channel blockers, such as glinides and sulfonylurea drugs, can induce loss of ischemic preconditioning. This study aimed to investigate the effects of repaglinide, a hypoglycemic agent with an affinity for myocardial ATP-sensitive K (+)channels, on the results of consecutive exercise tests in patients with diabetes and multivessel coronary artery disease. METHODS: Forty-two patients with type 2 diabetes and chronic stable angina pectoris, and two-vessel or three-vessel disease participated in this study. The patients underwent two consecutive treadmill exercise tests (phase 1). On the day after these exercise tests, 2 mg of oral repaglinide was given to the patients. One week later, two exercise tests were repeated consecutively (phase 2). RESULTS: All patients achieved 1.0-mm ST-segment depression during the four exercise tests (T1, T2, T3, and T4). In phase 2, seven patients improved in time to onset of 1.0-mm ST-segment depression. The worsening of the time to onset of 1.0-mm ST-segment depression in phase 2 demonstrated ischemic preconditioning block in 83.3% of patients (P=0.0001). Even the postexercise electrocardiographic parameters (ST-segment depression morphology and magnitude and arrhythmias) were significantly different between the groups with and without pharmacologic ischemic preconditioning block (P=0.031). CONCLUSIONS: Repaglinide, an oral hypoglycemic agent with ATP-sensitive K(+) channel-blocker activity, eliminated the myocardial ischemic preconditioning in patients with coronary disease and diabetes.
Subject(s)
Angina Pectoris/complications , Carbamates/pharmacology , Diabetes Mellitus, Type 2/complications , Hypoglycemic Agents/pharmacology , Ischemic Preconditioning, Myocardial , Piperidines/pharmacology , Electrocardiography , Exercise Test/drug effects , Female , Humans , Male , Middle Aged , Time FactorsABSTRACT
Congenital generalized lipodystrophy (CGL) is a rare autosomal recessive disorder caused by mutations in AGPAT2 and Gng3lg. We screened for mutations in AGPAT2 and Gng3lg in 26 families with CGL and one family with Brunzell syndrome. We found mutations in either AGPAT2 or Gng3lg in all but four probands, including three novel mutations in AGPAT2, A712T (Lys215X), IVS3-1G-->C, and C636A (Phe189X). In three siblings with Brunzell syndrome, we identified a splice site mutation (IVS4-2A-->G) in AGPAT2, showing that AGPAT2 mutations can also cause Brunzell syndrome. Eighteen CGL patients from 15 families from the same region of northeastern Brazil were homozygous for a frameshift mutation (669insA of AF05149) in Gng3lg. Despite having the same mutation, the subjects had widely divergent clinical manifestations. In our subjects, there did not appear to be any distinguishing clinical characteristics between CGL subjects with AGPAT2 or Gng3lg mutations with the exception of mental retardation in carriers of Gng3lg. In summary, mutations in AGPAT2 and Gng3lg are approximately equally represented in CGL; despite harboring the same Gng3lg mutation, subjects may have widely divergent clinical manifestations, suggesting modifying influences of other genes and/or environment; and Brunzell syndrome may be caused by a mutation in AGPAT2.
Subject(s)
Acyltransferases/genetics , GTP-Binding Protein gamma Subunits/genetics , Lipodystrophy/genetics , Polymorphism, Genetic , 1-Acylglycerol-3-Phosphate O-Acyltransferase , Adolescent , Adult , Child , Child, Preschool , Female , Frameshift Mutation , Homozygote , Humans , Infant , Lipodystrophy/congenital , Male , Phenotype , RNA Splice Sites/geneticsABSTRACT
This was an open-label, randomised 26-week study to determine the effects of adding 4 mg rosiglitazone (Avandia) daily to existing sulphonylurea (SU) therapy in patients with type 2 diabetes from India, Brazil, The Philippines, Thailand, Argentina and Tunisia. Of the 348 patients, 175 received 2 mg rosiglitazone twice daily plus SU (RSG+SU) and 173 received SU alone (at their normal dose). The RSG+SU group showed a significant reduction in HbA1c (mean HbA1c 9.05% at baseline, 7.92% at 26 weeks, mean change -1.13 (95% Cl -1.37, -0.89)). Mean HbA1c essentially remained unchanged in the control group (8.9 to 9.0%). The RSG+SU group showed a significant decrease in fasting plasma glucose concentration (FPG) (mean FPG 198.7 mg/dl at baseline, 160.3 mg/dl at 26 weeks, mean change -38.4 (95% Cl -47.1, -29.7)) while the controls showed a non-significant increase from 194 to 200 mg/dl. Significantly more patients in the RSG+SU group achieved FPG < 140 mg/dl, > or = 0.7% decrease in HbA1c, and > or = 30 mg/dl decrease in FPG between baseline and week 26 than the controls (p = 0.0001 in each case). Adverse events were similar in both groups; more patients in the RSG+SU group reported hypoglycaemia, but most cases were mild. This study shows that adding rosiglitazone to existing SU treatment improves glycaemic control and is well-tolerated in patients with type 2 diabetes from a wide range of non-Western countries.
Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/therapeutic use , Sulfonylurea Compounds/therapeutic use , Thiazoles/therapeutic use , Thiazolidinediones , Adult , Aged , Aged, 80 and over , Developing Countries , Drug Therapy, Combination , Female , Humans , Hypoglycemic Agents/administration & dosage , Male , Middle Aged , Rosiglitazone , Sulfonylurea Compounds/administration & dosage , Thiazoles/administration & dosage , Treatment OutcomeABSTRACT
OBJECTIVE: To determine the frequency and significance of diabetes mellitus (DM)-related autoantibodies in children with autoimmune hepatitis (AIH). RESEARCH DESIGN AND METHODS: Anti-islet cell antibodies (ICA), insulin autoantibodies (IAA), and anti-glutamic acid decarboxylase (GAD65) antibodies were assessed in 28 children (25 female) with AIH before and after 3-9 years of therapy with azathioprine and prednisone. RESULTS: There was biochemical and clinical remission of AIH activity in 76% of the children after 1 year of immunosuppressive therapy. Positive ICA and IAA were found in 60.7% and 18.5% of the patients, decreasing to 38.5% and 12% after 3-9 years of therapy. Anti-GAD autoantibodies were present in only one patient who had Graves' disease, high ICA titer, and developed type 1 DM after 3 years. After 3-9 years of follow up, all had normal fasting glycemia, glycosylated hemoglobin (HbA1c), and, with a single exception, normal responses to oral glucose tolerance testing. No increase in the frequencies of HLA antigens was observed in ICA- and IAA-positive patients compared to antibody-negative patients or a control population. The majority of the patients with HLA-DRB1*03 or DRB1*04, however, were positive for ICA (7/10), and three of them had IAA. The frequency of high risk HLA DQB1*0302 or DQB1*02 alleles was low and similar to control frequencies, indicating low-risk for DM despite the presence of DM-related autoimmunity markers. CONCLUSIONS: AIH in childhood is associated with high frequency of ICA and IAA, with less than expected rates of progression to DM. Immunosuppression reduced ICA and IAA frequency and titers.
Subject(s)
Autoantibodies/biosynthesis , Diabetes Mellitus/immunology , Hepatitis, Autoimmune/immunology , Actins/immunology , Adolescent , Animals , Antibodies, Antinuclear/analysis , Autoantibodies/analysis , Child , Child, Preschool , Cytochrome P-450 CYP2D6/immunology , Cytosol/immunology , Diabetes Complications , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/immunology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/immunology , Female , Fluorescent Antibody Technique, Indirect , Glutamate Decarboxylase/immunology , Hepatitis, Autoimmune/complications , Humans , Insulin/immunology , Islets of Langerhans/immunology , Isoenzymes/immunology , Male , Muscle, Smooth/immunology , Rats , Rats, WistarABSTRACT
OBJECTIVE: Glucose intolerance is frequently associated with an altered plasma lipid profile and increased cardiovascular disease risk. Nonetheless, lipid metabolism is scarcely studied in normolipidemic glucose-intolerant patients. The aim of this study was to investigate whether important lipid metabolic parameters, such as the kinetics of LDL free and esterified cholesterol and the transfer of lipids to HDL, are altered in glucose-intolerant patients with normal plasma lipids. METHODS: Fourteen glucose-intolerant patients and 15 control patients were studied; none of the patients had cardiovascular disease manifestations, and they were paired for age, sex, race and co-morbidities. A nanoemulsion resembling a LDL lipid composition (LDE) labeled with 14C-cholesteryl ester and ³H-free cholesterol was intravenously injected, and blood samples were collected over a 24-h period to determine the fractional clearance rate of the labels by compartmental analysis. The transfer of free and esterified cholesterol, triglycerides and phospholipids from the LDE to HDL was measured by the incubation of the LDE with plasma and radioactivity counting of the supernatant after chemical precipitation of non-HDL fractions. RESULTS: The levels of LDL, non-HDL and HDL cholesterol, triglycerides, apo A1 and apo B were equal in both groups. The 14C-esterified cholesterol fractional clearance rate was not different between glucose-intolerant and control patients, but the ³H-free-cholesterol fractional clearance rate was greater in glucose-intolerant patients than in control patients. The lipid transfer to HDL was equal in both groups. CONCLUSION: In these glucose-intolerant patients with normal plasma lipids, a faster removal of LDE free cholesterol was the only lipid metabolic alteration detected in our study. This finding suggests that the dissociation of free cholesterol from lipoprotein particles occurs in normolipidemic glucose intolerance and may participate in atherogenic signaling.
Subject(s)
Cardiovascular Diseases/etiology , Cholesterol, LDL/blood , Glucose Intolerance/blood , Lipid Metabolism , Lipoproteins, HDL/blood , Nanoparticles , Adult , Aged , Case-Control Studies , Cholesterol, LDL/pharmacokinetics , Emulsions , Female , Humans , Lipids/pharmacokinetics , Lipoproteins, HDL/pharmacokinetics , Male , Middle Aged , Nanoparticles/analysis , Triglycerides/blood , Triglycerides/pharmacokineticsABSTRACT
OBJECTIVE: Roux-en-Y gastric bypass (RYGB) ameliorates type 2 diabetes in severely obese patients through mechanisms beyond just weight loss, and it may benefit less obese diabetic patients. We determined the long-term impact of RYGB on patients with diabetes and only class I obesity. RESEARCH DESIGN AND METHODS: Sixty-six consecutively selected diabetic patients with BMI 30-35 kg/m(2) underwent RYGB in a tertiary-care hospital and were prospectively studied for up to 6 years (median 5 years [range 1-6]), with 100% follow-up. Main outcome measures were safety and the percentage of patients experiencing diabetes remission (HbA(1c) <6.5% without diabetes medication). RESULTS: Participants had severe, longstanding diabetes, with disease duration 12.5 ± 7.4 years and HbA(1c) 9.7 ± 1.5%, despite insulin and/or oral diabetes medication usage in everyone. For up to 6 years following RYGB, durable diabetes remission occurred in 88% of cases, with glycemic improvement in 11%. Mean HbA(1c) fell from 9.7 ± 1.5 to 5.9 ± 0.1% (P < 0.001), despite diabetes medication cessation in the majority. Weight loss failed to correlate with several measures of improved glucose homeostasis, consistent with weight-independent antidiabetes mechanisms of RYGB. C-peptide responses to glucose increased substantially, suggesting improved ß-cell function. There was no mortality, major surgical morbidity, or excessive weight loss. Hypertension and dyslipidemia also improved, yielding 50-84% reductions in predicted 10-year cardiovascular disease risks of fatal and nonfatal coronary heart disease and stroke. CONCLUSIONS: This is the largest, longest-term study examining RYGB for diabetic patients without severe obesity. RYGB safely and effectively ameliorated diabetes and associated comorbidities, reducing cardiovascular risk, in patients with a BMI of only 30-35 kg/m(2).
Subject(s)
Cardiovascular Diseases/etiology , Diabetes Mellitus, Type 2/surgery , Gastric Bypass , Adult , Blood Glucose/metabolism , Female , Glycated Hemoglobin/metabolism , Humans , Male , Middle Aged , Remission Induction , Risk Factors , Weight LossABSTRACT
Gastric bypass surgery causes resolution of type 2 diabetes (T2DM), which has led to the hypothesis that upper gastrointestinal (UGI) tract diversion, itself, improves glycemic control. The purpose of this study was to determine whether UGI tract bypass without gastric exclusion has therapeutic effects in patients with T2DM. We performed a prospective trial to assess glucose and ß-cell response to an oral glucose load before and at 6, 9, and 12 months after duodenal-jejunal bypass (DJB) surgery. Thirty-five overweight or obese adults (BMI: 27.0 ± 4.0 kg/m(2)) with T2DM and 35 sex-, age-, race-, and BMI-matched subjects with normal glucose tolerance (NGT) were studied. Subjects lost weight after surgery, which was greatest at 3 months (6.9 ± 4.9%) with subsequent regain to 4.2 ± 5.3% weight loss at 12 months after surgery. Glycated hemoglobin (HbA(1c)) decreased from 9.3 ± 1.6% before to 7.7 ± 2.0% at 12 months after surgery (P < 0.001), in conjunction with a 20% decrease in the use of diabetes medications (P < 0.05); 7 (20%) subjects achieved remission of diabetes (no medications and HbA(1c) <6.5%). The area under the curve after glucose ingestion was ~20% lower for glucose but doubled for insulin and C-peptide at 12 months, compared with pre-surgery values (all P < 0.01). However, the ß-cell response was still 70% lower than subjects with NGT (P < 0.001). DJB surgery improves glycemic control and increases, but does not normalize the ß-cell response to glucose ingestion. These findings suggest that altering the intestinal site of delivery of ingested nutrients has moderate therapeutic effects by improving ß-cell function and glycemic control.
Subject(s)
Diabetes Mellitus, Type 2/blood , Duodenum/surgery , Gastric Bypass , Glycated Hemoglobin/metabolism , Insulin-Secreting Cells/metabolism , Jejunum/surgery , Obesity, Morbid/blood , Adult , Aged , Blood Glucose/metabolism , Diabetes Mellitus, Type 2/surgery , Female , Gastric Bypass/methods , Glucose Tolerance Test , Humans , Insulin Resistance , Male , Middle Aged , Obesity, Morbid/surgery , Remission Induction , Weight Loss , Young AdultABSTRACT
BACKGROUND: The beneficial actions of exercise training on lipid, glucose and energy metabolism and insulin sensitivity appear to be in part mediated by PGC-1alpha. Previous studies have shown that spontaneously exercised rats show at rest enhanced responsiveness to exogenous insulin, lower plasma insulin levels and increased skeletal muscle insulin sensitivity. This study was initiated to examine the functional interaction between exercise-induced modulation of skeletal muscle and liver PGC-1alpha protein expression, whole body insulin sensitivity, and circulating FFA levels as a measure of whole body fatty acid (lipid) metabolism. METHODS: Two groups of male Wistar rats (2 Mo of age, 188.82 +/- 2.77 g BW) were used in this study. One group consisted of control rats placed in standard laboratory cages. Exercising rats were housed individually in cages equipped with running wheels and allowed to run at their own pace for 5 weeks. At the end of exercise training, insulin sensitivity was evaluated by comparing steady-state plasma glucose (SSPG) concentrations at constant plasma insulin levels attained during the continuous infusion of glucose and insulin to each experimental group. Subsequently, soleus and plantaris muscle and liver samples were collected and quantified for PGC-1alpha protein expression by Western blotting. Collected blood samples were analyzed for glucose, insulin and FFA concentrations. RESULTS: Rats housed in the exercise wheel cages demonstrated almost linear increases in running activity with advancing time reaching to maximum value around 4 weeks. On an average, the rats ran a mean (Mean +/- SE) of 4.102 +/- 0.747 km/day and consumed significantly more food as compared to sedentary controls (P < 0.001) in order to meet their increased caloric requirement. Mean plasma insulin (P < 0.001) and FFA (P < 0.006) concentrations were lower in the exercise-trained rats as compared to sedentary controls. Mean steady state plasma insulin (SSPI) and glucose (SSPG) concentrations were not significantly different in sedentary control rats as compared to exercise-trained animals. Plantaris PGC-1alpha protein expression increased significantly from a 1.11 +/- 0.12 in the sedentary rats to 1.74 +/- 0.09 in exercising rats (P < 0.001). However, exercise had no effect on PGC-1alpha protein content in either soleus muscle or liver tissue. These results indicate that exercise training selectively up regulates the PGC-1alpha protein expression in high-oxidative fast skeletal muscle type such as plantaris muscle. CONCLUSION: These data suggest that PGC-1alpha most likely plays a restricted role in exercise-mediated improvements in insulin resistance (sensitivity) and lowering of circulating FFA levels.
ABSTRACT
OBJECTIVE: Glucose intolerance is frequently associated with an altered plasma lipid profile and increased cardiovascular disease risk. Nonetheless, lipid metabolism is scarcely studied in normolipidemic glucose-intolerant patients. The aim of this study was to investigate whether important lipid metabolic parameters, such as the kinetics of LDL free and esterified cholesterol and the transfer of lipids to HDL, are altered in glucose-intolerant patients with normal plasma lipids. METHODS: Fourteen glucose-intolerant patients and 15 control patients were studied; none of the patients had cardiovascular disease manifestations, and they were paired for age, sex, race and co-morbidities. A nanoemulsion resembling a LDL lipid composition (LDE) labeled with 14C-cholesteryl ester and ³H-free cholesterol was intravenously injected, and blood samples were collected over a 24-h period to determine the fractional clearance rate of the labels by compartmental analysis. The transfer of free and esterified cholesterol, triglycerides and phospholipids from the LDE to HDL was measured by the incubation of the LDE with plasma and radioactivity counting of the supernatant after chemical precipitation of non-HDL fractions. RESULTS: The levels of LDL, non-HDL and HDL cholesterol, triglycerides, apo A1 and apo B were equal in both groups. The 14C-esterified cholesterol fractional clearance rate was not different between glucose-intolerant and control patients, but the ³H-free-cholesterol fractional clearance rate was greater in glucose-intolerant patients than in control patients. The lipid transfer to HDL was equal in both groups. CONCLUSION: In these glucose-intolerant patients with normal plasma lipids, a faster removal of LDE free cholesterol was the only lipid metabolic alteration detected in our study. This finding suggests that the dissociation of free cholesterol from lipoprotein particles occurs in normolipidemic glucose intolerance and may participate in atherogenic signaling.
Subject(s)
Adult , Aged , Female , Humans , Middle Aged , Cardiovascular Diseases/etiology , Cholesterol, LDL/blood , Glucose Intolerance/blood , Lipid Metabolism , Lipoproteins, HDL/blood , Nanoparticles , Case-Control Studies , Cholesterol, LDL/pharmacokinetics , Emulsions , Lipids/pharmacokinetics , Lipoproteins, HDL/pharmacokinetics , Nanoparticles/analysis , Triglycerides/blood , Triglycerides/pharmacokineticsABSTRACT
BACKGROUND/AIMS: Obesity and diabetes mellitus (DM) are associated with pancreatic cancer. The present study evaluated tumor staging and resection of pancreatic adenocarcinoma (PaC) according to previous Body Mass Index (BMI), BMI on admission and DM duration. METHODS: A retrospective analysis of 151 consecutive patients with PaC was performed: 73 were evaluated according to BMI preceding tumor-related weight loss and BMI on admission; 118 according to DM diagnosis; and 38 were assessed according to DM duration (less than 1 year [recent-onset] versus more than 2 years [long-standing]). RESULTS: There was no difference in the prevalence of tumor stage III or IV between previously normal weight and overweight/obese patients (56 vs. 42%, NS). Tumor resection rate was higher in previously obese than in previously lean patients (58 vs. 24%, p < 0.05). Tumor staging and resection were similar between normal weight and overweight/obese patients considering BMI on admission and diagnosis of DM. Weight loss was more pronounced in diabetic than in non-diabetic patients (21.7 vs. 13.3%, p < 0.01). Tumor staging and resection were similar between recent-onset and long-standing diabetic patients. CONCLUSION: Tumor resection rate was lower in previously normal weight patients. Diabetics lost more weight than non-diabetic patients. Neither BMI on admission nor the presence of DM nor DM duration influenced tumor staging or resection in PaC patients.
Subject(s)
Adenocarcinoma/pathology , Body Mass Index , Diabetes Complications/pathology , Diabetes Mellitus/pathology , Pancreatic Neoplasms/pathology , Adenocarcinoma/complications , Adenocarcinoma/surgery , Female , Hospitals, University , Humans , Male , Middle Aged , Neoplasm Staging , Pancreatic Neoplasms/complications , Pancreatic Neoplasms/surgery , Time FactorsABSTRACT
BACKGROUND: Lipoatrophic diabetes is characterized by the near absence of adipose tissue and the presence of insulin-resistant diabetes. Fasting hypertriglyceridaemia and increased postprandial lipidaemia are also present, but the metabolism of chylomicrons, the triglyceride-rich lipoproteins in the circulation that carry the dietary fats absorbed by the intestine, was not specifically investigated. Because both the activity of insulin-dependent lipoprotein lipase that catalyses the chylomicron lipolysis and the storage of the lipolysis products are affected in the disease, it is important to evaluate how those changes may ultimately affect the chylomicron lipolysis and removal of chylomicron remnants from the circulation. OBJECTIVE: The aim of the study was to evaluate the chylomicron intravascular metabolism in patients with lipoatrophic diabetes. PATIENTS: Six patients with lipoatrophic diabetes (four females, two males) aged 22.2 +/- 4.4 years, with body mass index (BMI) 21.6 +/- 3.6 kg/m(2), were compared with 12 healthy control subjects (seven females, five males) aged 24.3 +/- 2.1 years with BMI 22.5 +/- 2.7 kg/m(2). MEASUREMENTS: The plasma kinetics of intravenously injected chylomicron-like emulsions labelled with (3)H-triglycerides ((3)H-TG) and with (14)C-cholesteryl esters ((14)C-CE) were determined, the former tracing the chylomicron lipolysis by lipoprotein lipase and the latter the removal of chylomicron remnants from the plasma. RESULTS: Triglyceride values (8.3 +/- 9.2 mmol/l) in the patients were higher (P < 0.005) and high density lipoprotein (HDL) cholesterol values (0.8 +/- 0.2 mmol/l) lower (P < 0.0005) than in controls (0.7 +/- 0.2 and 1.3 +/- 0.4 mmol/l, respectively) whereas total cholesterol, apoprotein B (apo B) and apo A1 were similar. The fractional clearance rate (FCR, in min(-1)) of (3)H-TG was 0.014 +/- 0.016 and the FCR of (14)C-CE was 0.008 +/- 0.012 in the patients and 0.046 +/- 0.024 and 0.024 +/- 0.012 in the controls, respectively (P < 0.05). Thus FCRs of both emulsion labels were markedly reduced in the patients, indicating that lipolysis and remnant removal were diminished. Diminished remnant removal may be due to either deficient lipolysis or deficient removal mechanisms. CONCLUSION: The metabolism of chylomicrons tested by the emulsion method is impaired in lipoatrophic diabetes.
Subject(s)
Cholesterol Esters/pharmacokinetics , Chylomicrons/pharmacokinetics , Diabetes Mellitus, Lipoatrophic/metabolism , Triglycerides/pharmacokinetics , Adult , Carbon Radioisotopes/pharmacokinetics , Case-Control Studies , Emulsions , Female , Humans , Injections, Intravenous , Male , Statistics, Nonparametric , Tritium/pharmacokineticsABSTRACT
Nodular corticotrope hyperplasia is a rare pathology causing Cushing's syndrome owing to a primary pituitary disease or ectopic CRH production. In this study, we evaluated the laboratory and pathological findings and results of transsphenoidal pituitary surgery in four patients with Cushing's disease. Dynamic tests of pituitary-adrenal function (dexamethasone suppression, metyrapone, CRH, and DDAVP tests) were done before and after transsphenoidal pituitary surgery. Plasma and total urinary cortisol, serum 11-deoxycortisol, and plasma ACTH were determined by RIA. Hormonal dynamic tests and radiologic studies were compatible with a pituitary ACTH source. The transsphenoidal surgery revealed the presence of corticotrope hyperplasia confirmed by immunoperoxidase stain and a preserved reticulum framework in the removed pituitary tissue of these four patients. The pituitary surgery led to a short period of improvement in two of the patients (1 and 4), a 3-yr remission in one patient (patient 2), and no improvement in one (patient 3). We conclude that although our patients appear to have inadequate suppression with high-dose dexamethasone, there is no way to diagnose this pathology presurgically, and that total hypophysectomy, bilateral adrenalectomy, and irradiation are the only alternatives for definitive treatment. A CRH-secreting ectopic tumor could not be found in our patients either before or after surgery in the follow-up period.
ABSTRACT
O objetivo do estudo foi determinar se a Gordura intra Abdominal medida pela Ultra-Sonografia (GAUS) em homens e mulheres tem associação com os fatores de risco cardiovascular, comparar essa medida com a circunferência abdominal e diâmetro sagital para precisar qual destes métodos é o melhor preditor de risco cardiovascular (CV), e tentar encontrar um ponto de corte para GAUS que possa definir maior risco de doença CV. Cento e noventa e um homens sadios e 231 mulheres sadias foram submetidas à medidas antropométricas, medidas de pressão arterial sistêmica e dosagens laboratoriais para colesterol, HDL, triglicerídeos e glicemia. A ultra-sonografia intra-abdominal foi realizada para medir espessura visceral. A amostra foi dividida em três grupos de acordo com a presença dos seguintes fatores de risco cardiovascular: 1) grupo de moderado risco - presença de dois ou mais dos fatores: col > 200mg/dL, HDL-colesterol < 45mg/dL, TG > 200mg/dL, Glic > 126mg/dL, PAs > 140mmHg, PAd > 90mmHg; 2) grupo de alto risco com dois ou mais dos fatores: total col > 240mg/dL, HDL-colesterol < 35mg/dL, TG > 200mg/dL +HDL < 35mg/dL, Glic > 126mg/dL, PAs > 140mmHg, PAd > 90mmHg; 3) grupo sem risco: com um ou nenhum dos fatores de risco presentes. Os resultados mostraram que a GAUS tem associação com todos os fatores de risco cardiovascular e tem melhor especificidade e acurácia que a circunferência abdominal e o diâmetro sagital. O valor de 7cm para ambos os sexos foi o ponto de corte para GAUS para predizer risco moderado; 8 e 9cm foram os pontos de cortes obtidos para GAUS para predizer alto risco CV em homens e mulheres, respecti- vamente. A GAUS é um método útil de determinar espessura visceral e parece ser capaz de predizer risco cardiovascular.