ABSTRACT
BACKGROUND: Digoxin-like immunoactivity (DLIA) reflects the presence of endogenous substances which are close to cardiac glycosides. These substances via inhibition of Na(+)-K(+)-ATPase increase intracellular calcium stores (Ca2+i) and may modulate various Ca(2+)-dependent mechanisms. Although DLIA are known primarily as hypertension and natriuresis promoting factors, several recent works have suggested that DLIA relates also to diabetes mellitus. The main stimulus for DLIA secretion represents volume-expansion. AIM OF STUDY: To assess relation of DLIA to glucose tolerance and insulin levels in pregnant women (PW). SUBJECTS AND METHODS: 1) 67 PW (DLIA measured by RIA-kit HUMA-LAB Kosice), 2) 53 PW (DLIA measured by RIA-kit ORION). PW were subdivided according to the glucose tolerance and insulin concentrations. RESULTS: 1. DLIA in hyperinsulinemic PW were significantly higher than in those with normal insulin levels. 2. DLIA significantly correlated with insulin levels as well as with insulinogenic index. 3. The increase in plasma glucose and insulinemia during OGTT was accompanied by a decrease in DLIA. These findings were independent of other measured parameters (age, body mass index, pregnancy induced weight gain, blood pressure and steroid hormones). CONCLUSIONS: These findings suggest that DLIA does not respond only to changes regarding sodium-retention and volume-expansion, but also to changes in glucose and insulin metabolism. Thus, DLIA could represent one of the markers of "specific" neurohumoral activation. However, the question of whether an elevation in DLIA may consequently modulate mechanisms of insulin secretion, insulin sensitivity, vascular reactivity and other Ca2+i-dependent mechanisms remains speculative. (Tab. 4, Fig. 4, Ref. 41).
Subject(s)
Diabetes, Gestational/blood , Digoxin , Glucose Intolerance/blood , Insulin/blood , Pregnancy Complications/blood , Saponins/blood , Blood Glucose/analysis , Cardenolides , Enzyme Inhibitors/blood , Female , Glucose Tolerance Test , Humans , Pregnancy , Radioimmunoassay , Sodium-Potassium-Exchanging ATPase/antagonists & inhibitorsABSTRACT
The authors examined 25 patients with diabetes mellitus type 2 (NIDDM) without vascular complications, treated by sulphonyl urea preparations, 12 hyperinsulinaemic (HI) non-diabetic subjects and 11 normoinsulinaemic healthy subject s. Patients with NIDDM and HI non-diabetics had significantly elevated PAI-1 levels which correlated with the C-peptide level (r = 0.519, p < 0.001), triacylglycerols (TG) (r = 0.685, p < 0.001), BMI (r = 0.607, p < 0.001) and levels of endothelial markers such as von Willebrand s factor and thrombomodulin (TM). In the group of patients with NIDDM no relationship of PAI-1 and C-peptide was found and a significant correlation was found with TM levels (r = 0.609, p = 0.001) and TG levels (r = 0.476, p = 0.046). The results suggest that the endothelial department has an effect on the regulation of PAI-1 levels in patients with NIDDM.
Subject(s)
Diabetes Mellitus, Type 2/blood , Endothelium, Vascular/physiopathology , Plasminogen Activator Inhibitor 2/blood , Adult , Diabetes Mellitus, Type 2/physiopathology , Humans , Hyperinsulinism/blood , Hyperinsulinism/physiopathology , Middle Aged , Thrombomodulin/blood , Tissue Plasminogen Activator/blood , von Willebrand Factor/analysisABSTRACT
The digitalis-like substance (DLS), insulin resistance, and hyperglycemia are ascribed important roles in the pathogenesis of essential hypertension. The relationship between DLS and glycemia (insulinemia) was investigated in the present study. The levels of glycemia, insulinemia and DLS were measured during oral glucose load in a group of 18 subjects with various blood pressure values. Fasting levels of glycemia and insulinemia were in each subject within the physiological range and no correlation was found to exist between the fasting levels of DLS and glycemia (insulinemia). One hour after oral glucose load the increase of glycemia and insulinemia was significantly higher in the group of subjects with SBP > 140 and/or DBP > 90 mmHg than in normotensive subjects (p < 0.001). The increase in glycemia (insulinemia) was followed by a decrease of DLS. This contrary trend could be expressed as a significant inverse correlation between the change in plasma DLS and the change in glycemia (r = -0.660 p = 0.0039), and also between the change in plasma DLS and the change insulinemia (r = -0.687 p = 0.0023). These findings are assumed to suggest certain mechanisms involved in the pathophysiology of essential hypertension. (Tab. 3, Fig. 2, Ref. 20.)
