Pioglitazone Increases Amount of Epicardial Fat in Patients with Type 2 Diabetes Mellitus
L.J. Menting1, J.T. Jonker1, R.W. van der Meer1, van der, J.A. Romijn1, J.W.A. Smit1, A. Roos1, H.J. Lamb1, L.J. Rijzewijk2, M. Diamant2
Introduction: Diabetes mellitus is associated with an increased risk on cardiovascular disease and epicardial fat has been proposed as an additional cardiovascular risk factor. Treatment with pioglitazone leads to an improvement in glycemic control, but also increases body weight.
The primary aim was to evaluate the effect of pioglitazone on epicardial fat accumulation in patients with type 2 diabetes mellitus (DM2). Yet there is no golden standard to measure epicardial fat. Therefore we developed a new and reliable method to accurately quantify epicardial fat. The secondary aim was to assess the relationship of epicardial fat to anthropometric measurements and fat distribution in these patients.
Material and Methods: Seventy-seven male patients with DM2 were included in this study (mean± SEM, age 56.5 ± 0.6 yr; HbA1c 7.1 ± 0.1%), without cardiac ischemia. Patients were randomly assigned to pioglitazone (30mg/day) or metformin (2000mg/day) and matching placebo during 24 weeks. Epicardial fat was measured by magnetic resonance imaging (MRI) scans in the horizontal and left vertical long-axis plane. Visceral and abdominal subcutaneous fat were measured by MRI at the L4-L5 level. Myocardial and hepatic triglyceride content (TG) were determined by 1H magnetic resonance spectroscopy.
Results: Epicardial fat correlated with abdominal visceral fat (r = 0.53, pConclusion: Pioglitazone increases right ventricular epicardial fat in type 2 DM patients, whereas it does not affect visceral fat and EAT at the left ventricle. Moreover, the medicine increases body weight, BMI and subcutaneous fat. Furthermore pioglitazone decreases the hepatic TG content. There is a correlation between EAT and BMI, body weight, abdominal subcutaneous and visceral fat in type 2 DM patients.
Comparable Diagnostic Performance of the 1 µg ACTH Test and the 250 µg ACTH Test for the Diagnosis of Adrenal Insufficiency
O.M. Dekkers, J.M. Timmermans
Introduction: For assessment of adrenal secretory reserve, the 1 µg and 250 µg ACTH tests are available. Main aim of this study was to compare the diagnostic performance of the 1 µg and 250 µg ACTH test in a large cohort of patients.
Material and Methods: Diagnostic, single center study including all consecutive patients suspected of possible primary or secondary adrenal insufficiency between January 2004 and December 2007 who had both ACTH tests (1 µg and 250 µg) (N=209). A Bland Altman plot with limits of agreement was made to compare these two tests. In a subpopulation (N=55), the cortisol responses in the two ACTH tests (cortisol response 30 min after administration of ACTH) were compared to the maximal cortisol response during an insulin tolerance test (ITT).
Results: The mean difference between the cortisol responses in the two ACTH tests was only 0.03 µmol/l (95% CI 0.015-0.042). The diagnostic performances of the two tests were not different (p=0.49) using a cut-off value of 0.55 µmol/L. The limits of agreement ranged from -0.17 to 0.22. The sensitivity and specificity for the 1 µg test were 0.93 and 0.67, respectively. For the 250 µg test 0.88 and 0.53, respectively. The mean difference between the response of the 1ug test and the ITT was -0.003 µmol/l (95% CI -0.03-0.03). The mean difference between the response of the 250 µg test and the ITT was -0.03 µmol/l (95%CI -0.07-0.07).
Conclusion: This study showed that the 1µg and the 250 µg ACTH test have comparable diagnostic performances in patients with suspected adrenal insufficiency, because of a minimal difference in mean outcome. Compared to the ITT, the 1 µg test seems to be slightly better than the 250 µg ACTH test.
State of Antioxidant System in Liver of Rats in the Condition of Experimental Diabetes
G. Kozak, B. Melekh, A. Revura, N. Phartushok, N. Khavrona, A. Sklyarov
Danylo Halytsky Lviv National Medical University
Introduction: Diabetes is one of the most widespread diseases. Metabolic disbalance, which arises up from diabetes, is the basic reason in developing of oxidation stress., that leads to increase in processes of lipoperoxidation and antioxidant defense.
Material and Methods: Ten Wistar male rats weighting 180-200 grams have been investigated. Diabetes mellitus was modeled by introducing streptosotocin (50mg/kg of total body weight). The samples of homogenate were taken on 14th day of development of the pathological process, after the induction. The level of hyperglycemia was the criterion of development of disease (18-22 µmole/l), comparing with a control group – 7,2-8,4 µmole/l. made of 10 rats. We estimated nitrogen oxide (NO) according to the Green L.C.,David A.W. method(1982); Superoxide dismutase (SOD) according to Sandstrom J., Nilsson P., Karlsson R. method1994; oxidative modification of proteins(OMP) according to the E.E. Doubininoi method (2000).
Results: The research results show the increase of nitrogen oxide (NO) production in streptosotocin diabetes to 0,751±0,046 mcmol/mg protein in the group of animals with diabetes (control 0,485±0,029 mcmol/mg protein) in the homogenate. The OMP level of carbonil groups increased to 42,5±5,4 OOG/mg protein in the group of animals with diabetes (control 7,2±1,9 OOG/mg protein), and OMP level of basic groups increased to 20,3±3,2 OOG/mg protein in the group of animals with diabetes (control 1,2±0,76 OOG/mg protein). SOD activity was increased to 146,03±11,3 mcmol NST/hv mg protein in the group of animals with diabetes (control 88,82±9,4 mcmol NST/hv mg protein).
Conclusion: The activity of oxidative modification of proteins and antioxidant defence was increased as a result of passing oxidation stress. But level of stable metabolite of nitrogen was rised, that shows on inability of the antioxidant system in a complete measure to counteract the active radicals, which are producted in excessive quantitavely in diabetes.
Altered Expression of Novel Components of Renin-Angiotensin System During the Development of Spontaneous Hypertension
M.O. Olvedy1, P.O. Ochodnicky1, P.K. Krenek1, K.M. Mackovicova1, F.K. Kristek2, S.C. Cacanyiova2, J.K. Kyselovic1
1Faculty of Phramacy, Commenius University
2Institute of Normal and Pathological Physiology
Introduction: Renin-angiotensin system(RAS), the principal regulator of blood pressure, may be involved in the development of essential hypertension. Angiotensin converting enzyme (ACE), angiotensin II (AngII) and its receptor (AT1) represent a well-known axis of RAS. The activation of this axis leads to vasoconstriction and increase in blood pressure. Novel local components of RAS were discovered recently, including angiotensin converting enzyme 2 (ACE2) converting AngII into angiotensin(1-7). Ang(1-7) induces beneficial vasodilatory and antiproliferative effects through activation of Mas receptor. Moreover, Mas receptor interferes with AT1 receptor preventing its activation by Ang II. ACE2/Ang(1-7)/Mas forms a novel RAS axis balancing the activity of ACE/AngII/AT1 pathway in the regulation of blood pressure. We have hypothesized that changes in the expression of ACE, AT1, ACE2 and Mas receptor might be involved in the development of spontaneous hypertension. Additionally, we have examined whether perinatal AT1 receptor blockade with losartan may modulate these expressions.
Material and Methods: Blood pressure was measured by tail-cuff method in Wistar Kyoto rats (WKY, n=5), SHR (n=5) and SHR treated with losartan (20 mg/kg/day, p.o. twice daily) perinatally up to 9 weeks of age (n=5, dams during gestation/lactation period and pups from weaning at 4 weeks). At the age of 9 weeks, ACE, ACE2, AT1 receptor and Mas receptor mRNA levels in renal cortex and left ventricles were determined by Real-Time PCR.
Results and Conclusion: Perinatal losartan treatment (105±3 mmHg) prevented the rise in blood pressure (109±2 vs. 149±2 mmHg in WKY and SHRs, respectively). Compared to WKY, renal expression of ACE was unchanged in SHRs, whereas expression of AT1 receptor was significantly lowered. Renal expression of ACE2 was upregulated more than two-fold in SHR rats, while the expression of Mas receptor was substantially reduced. On the contrary, in the heart of SHRs, ACE expression was reduced when compared to WKY, while the AT1 receptor expression remained unchanged. In SHRs, the cardiac expression of ACE2 was not changed, but Mas expression was decreased. Despite of the modulation of blood pressure, losartan failed to affect ACE, AT1 and Mas expressions while it upregulated ACE2 in the kidneys of SHRs. Our results suggest that local RAS is regulated differentially in the kidney and the heart of SHRs. Downregulation of ACE, AT1 receptor and upregulation of ACE2 in SHR rats may represent mechanisms compensating to elevated blood pressure. However, lack of expression of Mas receptor may be involved in the development of spontaneous hypertension.