Glucose control during pregnancy in patients with type 1 diabetes correlates with fetal hemodynamics: a prospective longitudinal study

BACKGROUND

Maternal diabetes adversely affects fetal cardiovascular system development. Previous studies have reported that the fetuses of mothers with diabetes exhibit both structural and functional changes; nevertheless, prior studies have not examined the association between glucose control and fetal cardiac morphology and performance. Thus, the objective was to determine the association between fetal cardiac morphology and function and maternal glucose control in type 1 diabetes and to compare the differences in measured cardiac parameters between the fetuses of mothers with diabetes and healthy controls.

METHODS

In this prospective, longitudinal case-control study - including 62 pregnant women with type 1 diabetes mellitus and 30 healthy pregnant women - fetal cardiac assessment using B-mode, M-mode, and spectral pulsed-wave Doppler was performed in the second and third trimesters. In women with T1DM, glycated hemoglobin and data obtained from glucose sensors - including the percentage of time in, below, and above the range (TIR, TBR, and TAR, respectively), and coefficient of variation (CV) - were analyzed across three time periods: the last menstrual period to 13 (V1), 14-22 (V2), and 23-32 weeks (V3) of gestation. Fetal cardiac indices were compared between groups, and the correlation between glucose control and fetal cardiac indices was assessed.

RESULTS

At 28-32 weeks, the fetuses of women with T1DM exhibited increased left ventricular end-diastolic length, relative interventricular septum thickness, right ventricular cardiac output, and pulmonary valve peak systolic velocity compared with healthy controls. At 18-22 weeks, pulmonary and aortic valve diameters, left and right ventricular stroke volumes, and left cardiac output inversely correlated with the CV and glycated hemoglobin levels at V1 and V2. Furthermore, at 28-32 weeks, pulmonary and aortic valve diameters, left ventricular stroke volume, cardiac output, and right/left atrioventricular valve ratio inversely correlated with the TBR at V1, V2, and V3. Moreover, diastolic functional parameters correlated with the TAR and glycated hemoglobin levels, particularly after the first trimester.

CONCLUSION

In women with T1DM, maternal hyperglycemia during pregnancy correlates with fetal diastolic function, whereas glucose variability and hypoglycemia inversely correlate with fetal left ventricular systolic function in the second and third trimesters.

The rs10830963 Polymorphism of the MTNR1B Gene: Association With Abnormal Glucose, Insulin and C-peptide Kinetics

BACKGROUND

The MTNR1B gene encodes a receptor for melatonin, a hormone regulating biorhythms. Disruptions in biorhythms contribute to the development of type 2 diabetes mellitus (T2DM). Genetic studies suggest that variability in the MTNR1B gene affects T2DM development. Our aim was to compare the distribution of the genetic variant rs10830963 between persons differing in glucose tolerance in a sample of the Czech population (N=1206). We also evaluated possible associations of the polymorphism with insulin sensitivity, beta cell function, with the shape of glucose, insulin and C-peptide trajectories measured 7 times during a 3-hour oral glucose tolerance test (OGTT) and with glucagon response. In a subgroup of 268 volunteers we also evaluated sleep patterns and biorhythm.

RESULTS

13 persons were diagnosed with T2DM, 119 had impaired fasting blood glucose (IFG) and/or impaired glucose tolerance (IGT). 1074 participants showed normal results and formed a control group. A higher frequency of minor allele G was found in the IFG/IGT group in comparison with controls. The GG constellation was present in 23% of diabetics, in 17% of IFG/IGT probands and in 11% of controls. Compared to CC and CG genotypes, GG homozygotes showed higher stimulated glycemia levels during the OGTT. Homozygous as well as heterozygous carriers of the G allele showed lower very early phase of insulin and C-peptide secretion with unchanged insulin sensitivity. These differences remained significant after excluding diabetics and the IFG/IGT group from the analysis. No associations of the genotype with the shape of OGTT-based trajectories, with glucagon or with chronobiological patterns were observed. However, the shape of the trajectories differed significantly between men and women.

CONCLUSION

In a representative sample of the Czech population, the G allele of the rs10830963 polymorphism is associated with impaired early phase of beta cell function, and this is evident even in healthy individuals.

Blood glucose control by a model predictive control algorithm with variable sampling rate versus a routine glucose management protocol in cardiac surgery patients: a randomized controlled trial

CONTEXT

Elevated blood glucose levels occur frequently in the critically ill. Tight glucose control by intensive insulin treatment markedly improves clinical outcome.

OBJECTIVE AND DESIGN

This is a randomized controlled trial comparing blood glucose control by a laptop-based model predictive control algorithm with a variable sampling rate [enhanced model predictive control (eMPC); version 1.04.03] against a routine glucose management protocol (RMP) during the peri- and postoperative periods.

SETTING

The study was performed at the Department of Cardiac Surgery, University Hospital.

PATIENTS

A total of 60 elective cardiac surgery patients were included in the study.

INTERVENTIONS

Elective cardiac surgery and treatment with continuous insulin infusion (eMPC) or continuous insulin infusion combined with iv insulin boluses (RMP) to maintain euglycemia (target range 4.4-6.1 mmol/liter) were performed. There were 30 patients randomized for eMPC and 30 for RMP treatment. Blood glucose was measured in 1- to 4-h intervals as requested by each algorithm during surgery and postoperatively over 24 h.

MAIN OUTCOME MEASURES

Mean blood glucose, percentage of time in target range, and hypoglycemia events were used.

RESULTS

Mean blood glucose was 6.2 +/- 1.1 mmol/liter in the eMPC vs. 7.2 +/- 1.1 mmol/liter in the RMP group (P < 0.05); percentage of time in the target range was 60.4 +/- 22.8% for the eMPC vs. 27.5 +/- 16.2% for the RMP group (P < 0.05). No severe hypoglycemia (blood glucose < 2.9 mmol/liter) occurred during the study. Mean insulin infusion rate was 4.7 +/- 3.3 IU/h in the eMPC vs. 2.6 +/- 1.7 IU/h in the RMP group (P < 0.05). Mean sampling interval was 1.5 +/- 0.3 h in the eMPC vs. 2.1 +/- 0.2 h in the RMP group (P < 0.05).

CONCLUSIONS

Compared with RMP, the eMPC algorithm was more effective and comparably safe in maintaining euglycemia in cardiac surgery patients.

Increased subcutaneous and epicardial adipose tissue production of proinflammatory cytokines in cardiac surgery patients: possible role in postoperative insulin resistance

CONTEXT

Hyperglycemia and insulin resistance frequently occur in critically ill patients even without a history of diabetes.

OBJECTIVE

Our objective was to study the role of adipose tissue hormonal production in the development of insulin resistance in cardiac surgery patients. PARTICIPANTS, INTERVENTIONS, AND SETTINGS: Fifteen patients with elective cardiac surgery underwent blood sampling before, at the end, and 6, 12, 24, 48, and 120 h after the end of their operation. Epicardial and sc adipose tissue sampling was done at the beginning and at the end of surgery in the Department of Cardiac Surgery.

MAIN OUTCOME MEASURES

We measured serum concentrations and sc and epicardial adipose tissue mRNA expression of IL-6, monocyte chemoattractant protein-1 (MCP-1), TNF-alpha, leptin, resistin, and adiponectin and sc and epicardial adipose tissue mRNA expression of CD14, CD45, and CD68.

RESULTS

The rate of insulin infusion required to maintain euglycemia increased up to 7-fold 12 h after the operation, suggesting the development of insulin resistance. Serum IL-6 levels increased 43-fold 12 h after surgery. MCP-1 peaked 6-fold at the end of surgery. Smaller peaks of TNF-alpha and leptin appeared 6 and 12 h after surgery, respectively. Resistin levels peaked 4-fold 24 h after surgery, but adiponectin levels were not significantly affected. TNF-alpha and CD45 mRNA expression increased markedly during the operation in sc adipose tissue. IL-6, resistin, and MCP-1 mRNA expression increased in both sc and epicardial adipose tissue. Leptin, adiponectin, CD14, and CD68 mRNA expression did not change significantly.

CONCLUSIONS

Both sc and epicardial adipose tissue is a source of proinflammatory cytokines in cardiac surgery patients and may contribute to the development of postoperative insulin resistance.

Serum adiponectin and resistin concentrations in patients with restrictive and binge/purge form of anorexia nervosa and bulimia nervosa

To study the role of adipose tissue-derived hormones in the pathophysiology of eating disorders, circulating levels of adiponectin, resistin, and other hormonal and metabolic parameters were measured in 16 females with the restrictive subtype of anorexia nervosa (R-AN), 10 females with the binge/purge subtype of anorexia nervosa (P-AN), 15 females with bulimia nervosa (BN), and 12 age-matched healthy females (C). Body mass index (BMI), body fat content, and serum leptin levels were severely decreased in R-AN and moderately decreased in P-AN patients, whereas the BN group did not differ from C in these parameters. Serum soluble leptin receptor levels were increased in R-AN and P-AN and unchanged in BN patients. Circulating adiponectin levels were inversely related to BMI and were unchanged in BN patients and increased by 53% in P-AN and by 96% in R-AN relative to C group, respectively. In contrast, resistin levels in malnourished R-AN and P-AN were not different from either C or BN groups and showed no significant relationship to BMI or body fat content. We suggest that increased adiponectin levels reflect decreased body fat content in AN patients. In contrast, circulating resistin levels do not appear to be closely related to the nutritional status.

[Serum concentrations of adiponectin in patients with restrictive and purgative subtype of mental anorexia]

BACKGROUND

The aim of our study was to compare serum concentrations of adiponectin, leptin and other selected parameters in female patients with restrictive subtype of anorexia nervosa (n=15), (RMA), binge/purge subtype of anorexia nervosa (n=11) (PMA) with age-matched healthy females, (C, n=14).

METHODS AND RESULTS

RMA patients had the most severely decreased body mass index (BMI) and serum leptin levels of the three groups studied. These parameters were also significantly lower in PMA relative to C group. (BMI: RMA 14.61 +/- 0.49 kg/m2, PMA 17.30 +/- 0.25 kg/m2, C 23.21 +/- 0.96 kg/m2; leptin: RMA 1.39 +/- 0.31 ng/ml, PMA 3.72 +/- 0.77 ng/ml, C 9.17 +/- 1.53 ng/ml). In contrast, serum adiponectin levels were markedly increased in RMA patients (57.28 +/- 4.86 ug/ml) relative to other groups (PMA 40,25 +/- 2.18 microg/ml, K 26.84 +/- 2.40 microg/ml). Serum leptin levels positively correlated with BMI in all groups studied (r = 0.56, p = 0.002), while the inverse relationship was found for adiponectin levels and BMI (r = -0.72, p = 0.000003). The hormonal concentrations were measured by commercially available RIA and ELISA kits.

CONCLUSIONS

The most significant changes of serum adiponectin and leptin levels were found in the RMA group with most severely decreased BMI and body fat content relative to rest of the groups. Possible role of increased adiponectin levels in the etiopathogenesis and/or metabolic changes in patients with anorexia nervosa is under the scope of our current investigations.

Soluble leptin receptor and leptin levels in pregnant women before and after delivery

Soluble leptin receptor is an extracellular domain of the leptin receptor that serves as the main leptin-binding protein and may play a role in the regulation of leptin tissue effects. The aim of our study was to assess serum concentrations of leptin, soluble leptin receptor, and other hormones involved in the regulation of leptin secretion in pregnant women before and after delivery. Serum leptin, cortisol, and tumor necrosis factor alpha (TNF-alpha) concentrations in 19 pregnant women before delivery were significantly higher than in healthy nonpregnant women (33.3+/-21.0 vs. 7.9+/-3.5 ng/mL, 1068.9+/-442.2 vs. 546.6+/-165.3 nmol/L, 4.4+/-1.1 vs. 3.4+/-1.2 ng/mL, respectively). In contrast, no differences between these groups were found in soluble leptin receptor levels. Delivery significantly decreased serum leptin and cortisol levels and increased soluble leptin receptor levels (12.3+/-9.1 ng/mL, 749.6+/-205.3 nmol/L, 23.3+/-7.9 U/mL, respectively). Soluble leptin receptor levels after delivery became higher than in the control group. We conclude that serum leptin and serum soluble leptin-receptor levels are significantly affected by pregnancy and delivery. The regulation of leptin levels in this group of patients appears to be distinct and independent of soluble leptin-receptor levels.