PURPOSE: This study aimed to determine the impaired glucose tolerance and diabetes prevalence in patients with essential hypertension (HT) and to compare the developed microvascular complications of these groups. MATERIALS AND METHODS: An oral glucose tolerance test (OGTT) was performed on 338 essential hypertensive cases and glucose tolerances were classified according to ADA-2002 criteria. RESULTS: Of the 338 cases, 32 people had diabetes (DM, 9.46%), 78 people had glucose intolerance (IGT, 23.1%), and 228 people had only hypertension but not IGT and DM (67.4%). Both the mean ages of the DM group (56.9 +/- 6.7 years, p = 0.002) and IGT group (56.3 +/- 8.4 years, p = 0.003) were older than the mean age of the control group (51.1 +/- 6.4 years). The risk of IGT development was found to be four times greater in male cases than female cases when compared to the control group (p = 0.004, add ratio = 4.194). There were no significant differences in the body mass indexes (BMI's), hypertension durations, and microvascular complications between the groups. CONCLUSION: In conclusion, the risk of IGT and DM development in hypertensive cases increases with aging and longer hypertension duration. The risk of IGT development in hypertensive cases is four times more in males.
Aged ; Blood Glucose ; Diabetes Mellitus, Type 2/pathology/physiopathology ; Female ; Glucose Intolerance/pathology/*physiopathology ; Humans ; Hypertension/pathology/*physiopathology ; Male ; Middle Aged

BACKGROUNDThe effect of impaired glucose tolerance (IGT) on cardiac function during the chronic prediabetes state is complicated and plays an important role in clinical outcome. However, the molecular mechanisms are not fully understood. This study was designed to observe cardiac dysfunction in prediabetic rats with IGT and to determine whether glucose metabolic abnormalities, inflammation and apoptosis are linked to it.

METHODSThe IGT rat models were induced by streptozocin, and the heart functions were assessed by echocardiography. Myocardial glucose metabolism was analyzed by glycogen periodic acid-Schiff staining, and the pro-apoptotic effect of IGT was evaluated by TUNEL staining. Additionally, caspase-3 activation, macrophage migration inhibitory factor (MIF) and G-protein coupled receptor kinase 2 (GRK2) were detected by Western blotting in cardiac tissue lysates.

RESULTSArea-under-the-curve of blood glucose in rats injected with streptozotocin was higher than that in controls, increased by 16.28%, 38.60% and 38.61% at 2, 4 and 6 weeks respectively (F = 15.370, P = 0.003). Abnormal cardiac functions and apoptotic cardiomyocytes were observed in the IGT rats, the ejection fraction (EF) being (68.59 ± 6.62)% in IGT rats vs. (81.07 ± 4.59)% in controls (t = 4.020, P = 0.002). There was more glucose which was converted to glycogen in the myocardial tissues of IGT rats, especially in cardiac perivascular tissues. Compared to controls, the cleaved caspase-3, MIF and GRK2 were expressed at higher levels in the myocardial tissues of IGT rats.

CONCLUSIONSIGT in the prediabetes period resulted in cardiac dysfunction linked to abnormal glycogen storage and apoptosis. Additionally, MIF and GRK2 may be involved in the pathogenesis of cardiac dysfunction in prediabetes and their regulation may contribute to the design of novel diagnostic and therapeutic strategies for those who have potential risks for diabetic cardiovascular complications.

Animals ; Apoptosis ; drug effects ; Blotting, Western ; Disease Models, Animal ; Echocardiography ; G-Protein-Coupled Receptor Kinase 2 ; metabolism ; Glucose Intolerance ; chemically induced ; physiopathology ; Glucose Tolerance Test ; In Situ Nick-End Labeling ; Intramolecular Oxidoreductases ; metabolism ; Macrophage Migration-Inhibitory Factors ; metabolism ; Myocardium ; metabolism ; pathology ; Myocytes, Cardiac ; pathology ; Rats ; Streptozocin ; toxicity