Bone mineral density of both genders in Type 1 diabetes according to bone composition.

AIMS: This study is an investigation of the impact of Type 1 diabetes on bone mineral density (BMD) with regard to bone composition. MATERIAL AND METHODS: Thirty male and 30 premenopausal female patients with Type 1 diabetes (IDD) were retrospectively compared with an equal number of healthy individuals, matched on a person-to-person basis and to the reference population mean. BMD was measured at the L2-L4 vertebrae and femoral neck (FN) by dual energy X-ray absorptiometry (DXA). RESULTS: BMD absolute values were significantly lower in the diabetic than in the healthy males at vertebrae and FN (P<.05). The vertebral BMD values of diabetic women did not significantly differ, whereas those of FN were significantly lower compared with those of the healthy participants. FN age-adjusted BMD values (Z scores) were significantly lower than those of the healthy persons and the population reference mean in both genders (P=.01, <.001 for males and <.01 for females), whereas regarding the vertebrae, only in the diabetic males (P<.05 and <.01 respectively). The percentages of osteopenia and osteoporosis were significantly higher in the male compared to the female diabetic patients (P<.001). No significant correlations existed between the BMD values and diabetes duration, glycosylated hemoglobin (HbA1c) concentration, or age of diabetes onset. Similar results were obtained when applying stepwise multiple regression analysis to explain the BMD value variance. CONCLUSIONS: Young males with Type 1 diabetes exhibit significantly lower BMD values of trabecular and mixed cortical-trabecular bone, compared with matched healthy persons. Premenopausal females with Type 1 diabetes present significantly lower BMD values of mixed bone only. Blood glucose control and diabetes duration do not appear to influence BMD behavior.

Diabetes and premature menopause: is their co-existence detrimental to the skeleton?

OBJECTIVE: Premature menopause is a known risk factor for osteoporosis, whilst the influence of type 2 diabetes on bone mineral density (BMD) is still controversial. DESIGN AND METHODS: BMD values assessed by dual-energy X-ray absorptiometry (DXA) in L2-L4 vertebrae and the femoral neck (FN) of 40 diabetic women with premature menopause (D-EMP) were compared with those of 60 non-diabetic, prematurely menopausal women (EMP) and 60 diabetic women with normal menopause (D-NMP) who had been matched by age and body mass index (BMI). In all women, the time elapsed since menopause ranged between 10 and 25 years and the duration of diabetes exceeded 75% of the postmenopausal time period. The age of D-EMP women was 58.7+/-5 years (mean+/-1 s.d.), age at menopause 39.5+/-2.7, years since menopause 18.6+/-4.9, BMI 27.8+/-4.3 kg/m(2) and duration of diabetes 13.9+/-3.9 years. RESULTS: Vertebral BMD values of D-EMP women were significantly higher than those of EMP women (0.908+/-0.135 vs. 0.817+/-0.14 g/cm(2), P = 0.002), although there was no significant difference between D-EMP and D-NMP women (0.886+/-0.15 g/cm(2)). No significant differences were observed in FN BMD values between all groups. Age-adjusted BMD values (Z scores) of D-EMP women were higher than EMP women in both anatomic sites (P < 0.01), but did not differ from D-NMP women. In contrast to the other two groups, no statistically significant correlation was observed in D-EMP women between the BMD values of either anatomic area and the time elapsed since menopause. HbA(1c) values were positively correlated only to vertebral BMD values of the D-EMP group (P < 0.05). No correlation was observed between the BMD values and the duration of diabetes either in D-EMP or in D-NMP women. CONCLUSIONS: Type 2 diabetes seems to positively affect the mineral density of the trabecular bone in women with premature menopause. The duration of diabetes does not appear to influence bone mass.

Homocysteine, cortisol, diabetes mellitus, and psychopathology.

OBJECTIVE: This study investigates the association of homocysteine and cortisol with psychological factors in type 2 diabetic patients. METHOD: Homocysteine, cortisol, and psychological variables were analyzed from 131 diabetic patients. Psychological factors were assessed with the Eysenck Personality Questionnaire (EPQ), Hostility and Direction of Hostility Questionnaire (HDHQ), the Symptom Checklist 90-R (SCL 90-R), the Zung Self-Rating Depression Scale (ZDRS), and the Maudsley O-C Inventory Questionnaire (MOCI). Blood samples were taken by measuring homocysteine and cortisol in both subgroups during the initial phase of the study (T0). One year later (T1), the uncontrolled diabetic patients were reevaluated with the use of the same psychometric instruments and with an identical blood analysis. RESULTS: The relation of psychoticism and homocysteine is positive among controlled diabetic patients (P value = 0.006 < 0.05) and negative among uncontrolled ones (P value = 0.137). Higher values of cortisol correspond to lower scores on extraversion subscale (r(p) = -0.223, P value = 0.010). Controlled diabetic patients showed a statistically significant negative relationship between homocysteine and the act-out hostility subscale (r(sp) = -0.247, P = 0.023). There is a statistically significant relationship between homocysteine and somatization (r(sp) = -0.220, P = 0.043). CONCLUSIONS: These findings support the notion that homocysteine and cortisol are related to trait and state psychological factors in patients with diabetes mellitus type 2.

Pathogenesis of diabetic nephropathy.

Diabetic Nephropathy (DN) is the commonest cause of end-stage renal failure (ESRF) in the Western world. Diabetic nephropathy follows a well outline clinical course, starting with microalbuminuria through proteinuria, azotaemia and culminating in ESRF. Before the onset of overt proteinuria, there are various renal functional changes including renal hyperfiltration, hyperperfusion, and increasing capillary permeability to macromolecules. Basement-membrane thickening and mesangial expansion have long been recognized as pathological hallmark of diabetes. It has been postulated that DN occurs as a result of the interplay of metabolic and hemodynamic factors in the renal microcirculation. There is no doubt that there is a positive relationship between hyperglycaemia, which is necessary but not sufficient, and microvascular complications. The accumulation of advanced glycosylated end-products (AGEs), the activation of isoform(s) of protein kinase C (PKC) and the acceleration of the aldose reductase pathway may explain how hyperglycemia damages tissue. PKC is one of the key signaling molecules in the induction of the vascular pathology of diabetes. The balance between extracellular matrix production and degradation is important in this context. Transforming growth factor-beta (TGF-beta) appears to play a pivotal role in accumulation in the diabetic kidney. Hemodynamic disturbances are believed to be directly responsible for the development of glomerulosclerosis and its attendant proteinuria. There is familial clustering of diabetic kidney disease. A number of gene loci have been investigated to try to explain the genetic susceptibility to diabetic nephropathy. The genes coding for components of renin-angiotensin system have drawn special attention, due to the central role that this system plays in the regulation of blood pressure, sodium metabolism, and renal hemodynamics. Endothelial dysfunction is closely associated with the development of diabetic retinopathy, nephropathy and atherosclerosis, both in IDDM and in NIDDM. The pathogenesis of diabetic nephropathy is not clarified completely yet.

Comparative effects of glimepiride and glibenclamide on blood glucose, C-peptide and insulin concentrations in the fasting and postprandial state in normal man.

A single-center, randomised, placebo- controlled, cross-over study was conducted to characterize the new sulfonylurea glimepiride and to compare its profile of action with the second generation sulfonylurea glibenclamide. The total duration of each experiment was 5 hours. At zero time an i.v. injection of 2 and 4 mg glimepiride, 1 mg glibenclamide or placebo was given i.v. to 24 healthy volunteers. Blood samples were collected for three hours after the injection (0-3 hours, preprandial experiment). At 3 hours, a standard mixed meal was given (20%, of a 30 Kcal/Kg Body Weight diet) and blood samples were collected for 2 more hours (postprandial experiment). Pre-prandially (0-3 hrs) blood glucose (expressed as the area under the curve divided by the time) was significantly lower (p < 0.0001) after the administration of 2 and 4 mg glimepiride (3.8 +/- 0.22 and 3.5 +/- 0.3 mM respectively) compared to placebo (4.63 +/- 0.31 mM), but not compared to glibenclamide. Insulin and C-peptide were not different after glimepiride or glibenclamide. Both glimepiride and glibenclamide had similar effects on insulin secretion. Post-prandially (3-5 hrs) blood glucose was significantly higher after glibenclamide (6.54 +/- 0.8 mM) (p < 0.0001) than after 2 mg glimepiride (5.75 +/- 0.5 mM). Despite this C-peptide was significantly higher (p < 0.002) glibenclamide (5.7 +/- 1.5 ng/ml) compared to glimepiride (5.1 +/- 1.3 ng/ml); the trend was the same for insulin but the results were not significantly different (p = 0.06) In conclusion, in the fasting state, glimepiride and glibenclamide had similar effects on the changes in blood glucose levels after i.v. administration. After the meal, less pronounced hyperglycemia and lower insulin and C-peptide levels following glimepiride (2 mg) suggests either that glimepiride induces insulin secretion through a pathway which is different from that of glibenclamide or that glimepiride facilitates insulin action through extrapancreatic effects.

Oxytocin and diabetes mellitus: a strong biochemical relation. Review.

Oxytocin (OXT) is a neurohypophysial hormone which is synthesized in the paraventricular and supraoptic nuclei of the hypothalamus. OXT is currently attracting considerable attention because it has been discovered that it regulates various functions of behavior especially in the context of social interactions. OXT is a key component in bone formation, glycemia, male sexuality, cardiac differentiation and pregnancy and thus it is important to be further explored. The authors review various aspects of gestational diabetes, including definition, screening, diagnostic procedures, complications, clinical evaluation, indications of delivery and neonatal aspects. Not only the relation among diabetes mellitus, oxytocin and neurophysiology concerning erectile dysfunction, but also the role of OXT in the activity of arginine and vasopressin is investigated. It is imperative to develop technological and experimental methods that will be able to reveal the oxytocin and its potential.

Oxytocin and psychological factors affecting type 2 diabetes mellitus.

BACKGROUND: The aim of this study was to investigate the association of oxytocin with trait and state psychological factors in type 2 diabetic patients. METHODS: OXT and psychological variables were analyzed from 86 controlled diabetic patients (glycosylated haemoglobin A1c (HbA1c) < 7%) from 45 uncontrolled diabetic patients (HbA1c ≥ 7). Psychological characteristics were assessed with the Eysenck Personality Questionnaire (EPQ), while state psychological characteristics were measured with the Symptom Checklist 90-R (SCL 90-R). Blood samples were taken for measuring oxytocin in both subgroups during the initial phase of the study. One year later, the uncontrolled diabetic patients were reevaluated with the use of the same psychometric instruments. RESULTS: During the first evaluation of the uncontrolled diabetic patients, a statistically significant positive relationship between the levels of OXT and psychoticism in EPQ rating scale (P < 0.013) was observed. For controlled diabetic patients, a statistically significant negative relationship between oxytocin and somatization (P < 0.030), as well as obsessive-compulsive scores (P < 0.047) in SCL-90 rating scale, was observed. During the second assessment, the values of OXT decreased when the patients managed to control their metabolic profile. CONCLUSIONS: The OXT is in association with psychoticism, somatization, and obsessionality may be implicated in T2DM.

Anemia due to coadministration of renin-angiotensin-system inhibitors and PPARγ agonists in uncomplicated diabetic patients.

Therapy with either angiotensin converting enzyme inhibitors and angiotensin receptor blockers (ACEI/ARB) or thiazolidinediones (TZD) is associated with dose-dependent decrements in hematocrit and hemoglobin levels. We aimed to investigate the impact of the coadministration of TZD and ACEI/ARB on hematocrit and hemoglobin values in uncomplicated patients with type 2 diabetes mellitus and normal serum creatinine.Data from patients with type 2 diabetes currently followed, were reviewed and patients treated with ACEI/ARB and/or TZD were identified. For the purpose of this study the following 4 groups of 30 stable non-anemic diabetic patients each matched for age, gender, and BMI were formed. Group ACEI/ARB included patients on ACEI/ARB without TZD, group TZD included patients on TZD and antihypertensive agents other than ACEI/ARB, group ACEI/ARB/TZD consisted of patients on combined therapy with ACEI/ARB and TZD and the control group C included patients never exposed to ACEI/ARB or TZD. Clinical and laboratory data were collected prior to initiation of treatment and after 6 months.Neither hematocrit nor hemoglobin showed any significant change from baseline at the end of the study in group C. In both group ACEI/ARB and group TZD a small, but statistically significant reduction in hematocrit (~ 1% point) and hemoglobin levels (~ 0.3 g/dl) was seen. A greater statistically and clinically important reduction in hematocrit (~ 3% points) and hemoglobin (~ 1 g/dl) levels was observed in group ACEI/ARB/TZD. Furthermore, incident anemia at the end reached 7% in group TZD and 23% in group ACEI/ARB/TZD.Coadministration of RAS inhibitors and PPAR-γ agonists should be considered in the differential diagnosis of hematocrit lowering and anemia in uncomplicated type 2 diabetic patients with normal serum creatinine. Further studies are required to clarify the mechanism(s), the cardiovascular consequences and the cost utility of anemia workup in such patients.

Effect of hyperthyroidism on clearance and secretion of glucagon in man.

OBJECTIVE: Glucagon has been proposed to contribute to the increased glucose production found in hyperthyroidism. However, fasting plasma glucagon levels are not increased in hyperthyroidism suggesting that the activity of the α-cell is normal. Nevertheless, an increase in the clearance rate of glucagon may mask increased glucagon secretion. This study was designed to examine the effects of hyperthyroidism on the kinetics of glucagon. DESIGN AND METHODS: A primed-continuous infusion of glucagon was administered to 9 euthyroid and 9 hyperthyroid subjects at 3 sequential rates (1,200, 3,000 and 6,000 pg/kg/min, each given for 2 h). Arterialized blood was drawn at 15-30 min intervals for determination of glucagon. RESULTS: Fasting plasma glucagon levels were comparable in euthyroids (195±8 pg/ml) and hyperthyroids (231±16 pg/ml). During infusions (1,200, 3,000 and 6,000 pg/kg/min), plasma glucagon increased to 387±19, 624±44 and 977±51 pg/ml in euthyroids and to 348±23, 597±42 and 938±56 pg/ml in hyperthyroids respectively. At these infusion rates, metabolic clearance of glucagon (ml/kg/min) was 6.6±0.5, 7.4±0.6 and 7.9±0.5 in euthyroids and 12.6±2, 8.9±1 and 8.8±0.6 in hyperthyroids, respectively. Metabolic clearance of glucagon differed between hyperthyroids and euthyroids at 1 200 pg/kg/min infusion rate (p=0.001). The basal delivery rate of glucagon (ng/kg/min) was 1.3±0.1 in euthyroids and 2.9±0.6 in hyperthyroids (p=0.0005). CONCLUSIONS: In hyperthyroidism, the secretion and metabolic clearance rates of glucagon are increased. These effects may explain the changes in plasma glucagon levels observed in hyperthyroidism and support the important role of glucagon in increasing endogenous glucose production in this condition.

Diabetes in postmenopause: different influence on bone mass according to age and disease duration.

OBJECTIVE: Studies addressing the influence of diabetes mellitus on bone metabolism have yielded conflicting results. The aim of the present study is to investigate the bone mineral density (BMD) status of postmenopausal diabetic women with different ages or diabetes duration. METHODS: Two hundred postmenopausal women with type 2 diabetes (DM) and 800 postmenopausal healthy women (PMP), serving as control subjects, were studied. Subjects were divided into either 6 groups according to 5 year age segments, or 6 groups according to 5 year segments of diabetes duration. BMD was measured at the femoral neck and at the trochanter major with dual energy X-ray absorptiometry. RESULTS: Diabetic women studied as a whole, exhibited significantly higher BMD values compared to healthy postmenopausal women at both femoral neck and trochanter. Diabetic women of 48-53, 53-58, 58-63 and 63-68 age groups had significantly higher BMD values than the respective control groups, whereas BMD values of DM 73-78 were significantly lower compared to the PMP 73-78 group at both anatomic sites. When the same diabetic women were divided according to diabetes duration (DUR), groups DUR 6-10 and DUR 11-15 exhibited significantly higher BMD values at both anatomic sites compared to control groups. In contrast, BMD values of group DUR 21-25 were significantly lower only at the femoral neck. CONCLUSIONS: Type 2 diabetes mellitus' influence on bone metabolism seems to depend on the patient's disease duration and age. The initial positive effect on bone mass appears to be ameliorated as age or disease duration advance. Studies concerning type 2 diabetes and bone mass should take these parameters into account.

Comparative study of the therapeutic effects of glibenclamide or the fixed combination of glibenclamide-phenformin with those of gliclazide or chlorpropamide.

This study was designed to compare the therapeutic effects of glibenclamide or the fixed combination of glibenclamide-phenformin with those of gliclazide, chlorpropamide or biguanides in non-insulin-dependent diabetes. It is divided into two parts: a) in the retrospective study (473 subjects), glucose control of patients who were transferred from chlorpropamide, gliclazide, glibenclamide, glibenclamide + biguanide or metformin to the fixed combination glibenclamide-phenformin in the same tablet (2.5 mg and 25 mg, respectively) was monitored. A statistically significant decrease of blood glucose and glycosylated hemoglobin values was found under the combination of glibenclamide-phenformin contained in the same tablet in contrast to the values obtained with the treatment with glibenclamide, gliclazide, chlorpropamide, combination of glibenclamide and biguanides, metformin, and insulin. b) In the prospective study (57 subjects), the patients were transferred from chlorpropamide or gliclazide to glibenclamide for 3 months and then reallocated to the previous treatment for 3 additional months. It was found that under glibenclamide, glucose control was significantly better than under chlorpropamide or gliclazide. In conclusion, glibenclamide, a second generation sulfonylurea, and the fixed combination glibenclamide-phenformin in the same tablet are more effective compared to the other antidiabetic agents here studied and lead to a better control of type II diabetic patients. There was no increase in plasma lactic acid concentration in all patients studied before and after having received the fixed combination of glibenclamide-phenformin in the single tablet form.

The antidiabetic action of somatostatin-28 as assessed by the artificial endocrine pancreas: greater potency than somatostatin-14.

In order to investigate the action of somatostatin-28 (SS-28) on the metabolic homeostasis of insulin-dependent diabetics, we compared its effects to those of somatostatin-14 (SS-14) in terms of insulin sparing, changes in dextrose demands, glucose fluctuations and behavior of growth hormone and glucagon secretion. Eight insulin-dependent subjects were connected to Artificial Endocrine Pancreas (Biostator) for 84 hours during which they received intravenous infusions of either SS-14, SS-28 or isotonic saline in a randomized order, after a steady state of metabolism had been achieved. Five of the patients received SS-28 100 micrograms/h and SS-14 250 micrograms/h for 10 hours and three of them SS-28, 50 micrograms/h and SS-14 250 micrograms/h for 12 hours. Identical doses of both peptides were administered as bolus infusions prior to the continuous ones. Under SS-28 100 micrograms/h and SS-14 250 micrograms/h patients required 13.5 +/- 2.3 and 14.5 +/- 1.9 U of insulin respectively vs 40 +/- 5.6 U under isotonic saline infusion (mean +/- SEM, P less than 0.005 and P less than 0.01). At the same period the apparatus delivered 15 times more dextrose under SS-28 and 20 times more under SS-14. The magnitude of glucose fluctuations diminished from 64.6 +/- 2.47 mg% without to 41.4 +/- 2 mg% under SS-14 (P less than 0.01) and 46 +/- 3.8 mg% under SS-28 (P less than 0.02). Similar changes were observed in the remaining three patients who received SS-28 in the dose of 50 micrograms/h.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term effectiveness of a new alpha-glucosidase inhibitor (BAY m1099-miglitol) in insulin-treated type 2 diabetes mellitus.

In a double-blind, randomized study, miglitol (BAY m 1099), an alpha-glucosidase inhibitor, 100 mg tds or placebo was given orally with meals for a period of 24 weeks in 117 patients with Type 2 (non-insulin-dependent) diabetes mellitus (DM) treated with insulin. Fasting and 1 h postprandial plasma glucose and C-peptide were measured at the beginning and at the end of each 4-week interval and glycosylated haemoglobin was determined at day 0 and at the end of the 12th and 24th week. One hour postprandial plasma glucose was significantly lower in the miglitol group at the end of the 24th week (placebo: 11.6 +/- 1.5 vs miglitol: 8.2 +/- 1.5 mmol l-1, mean +/- SD, p = 0.001). Diabetes control improved in the same group as the HbA1 was lowered by 16% (p = < 0.0001) at the end of the treatment. Mild reversible adverse effects were observed in 37 patients of the miglitol group (mainly flatulence and mild hypoglycaemia) and 2 of the placebo group. Urinary glucose was rendered negative in 41 patients in the miglitol group only. Thus miglitol appears to be a safe and effective adjunct in the management of Type 2 DM, in association with insulin.

Therapeutic effect of glibenclamide in a fixed combination with metformin or phenformin in NIDDM patients.

The combination of a sulfonylurea with a biguanide improves the pancreatic beta-cell insulin secretion and the insulin utilization in peripheral tissues in NIDDM. This open, crossover, randomised and prospective study was designed to compare the effects of the fixed combination glibenclamide-metformin (GL-METF)-2.5 and 400 mg respectively, with the fixed combination glibenclamide-phenformin (GL-PHEN)-2.5 and 25 mg respectively, on NIDDM diabetes control. Thirty NIDDM patients, in ideal metabolic control, who were being treated with GL-PHEN were divided in two groups. One group received GL-PHEN for 12 weeks followed by 12 weeks treatment with GL-METF and the reverse treatment was given to the second group. A statistically significant decrease of post-prandial blood glucose (p = 0.034) and glycosylated haemo-globin (p < 0.02) values was observed under GL-METF treatment compared to those with GL-PHEN. The values of lactic acid were within normal limits during both treatments. The insulin secretion after breakfast was similar with both drug compounds. The BMI of the patients remained the same during a follow-up study of 24 weeks. Lipid metabolism did not change significantly during the trial and the safety parameters (renal and liver function, full blood count) remained unchanged. In conclusion, the administration of GL-METF leads to better diabetes control in NIDDM patients compared to that of GL-PHEN.