Abnormal levels of antioxidant defenses in a large sample of patients with hypertensive disorders of pregnancy.

Increased levels of oxidative stress have been demonstrated in Preeclampsia in previous studies, but this finding has not been established in other hypertensive disorders in pregnancy (HDP). We measured different markers of lipid peroxidation and antioxidant defenses by spectrophotometry or enzymoimmunoanalysis in 339 pregnant women: 85 with gestational hypertension (GH), 88 chronic hypertension (CH), 104 Preeclampsia and 62 healthy pregnant control women (PCW). Lower activity of superoxide dismutase and higher levels of catalase were found in GH, CH and preeclampsia compared with PCW (964.4±116.5, 970.0±120.4, 971.2±137.5 and 1063.4±133.7 U g(-1) Hb, P<0.001; and 313.0±71.7, 292.2±45.3, 297.1±47.2, 215.5±26.2 U mg(-1) Hb, P<0.0001; respectively). Regarding the glutathione REDOX cycle, we found the following in GH, CH and preeclampsia compared with PCW: a decrease in its reduced form (2.6±0.6, 2.7±0.8, 2.7±0.9, 3.3±1.3 µmol l(-1), P<0.003), a parallel increase in the oxidized form (185.6±68.9, 194.7±75.0, 184.3±78.3, 85.1±27.5 µmol l(-1), P<0.0001) and an increment in glutathione peroxidase (85.9±22.0, 86.4±20.9, 82.1±23.5 and 77.2±19.7 U g(-1) Hb, P<0.04) and glutathione reductase (6384.3±1261.9, 6724.6±1154.1, 6287.9±1399.9 and 6044.4±1208.4 mU g(-1) Hb, P<0.01, respectively). Nitrites/nitrates were higher in patients with preeclampsia than in PCW (31.50±15.08, 26.80±8.39 µmol l(-1), P<0.002). Although malondialdehyde and oxidized-LDL levels were similar among groups, free fatty acids were increased in every HDP (GH 514.6±194.6, CH 501.3±197.4, preeclampsia 555.2±230.1 µmol l(-1)) compared with PCW (351.4±146.1 µmol l(-1)), P<0.0001. Our results show an oxidation/reduction imbalance with an increase in oxidative stress coupled with a decreased capacity of antioxidant systems, not only in preeclampsia but also in every HDP.

Differences in the prevalence of metabolic syndrome and levels of C-reactive protein after puerperium in women with hypertensive disorders during pregnancy.

To measure high-sensitivity C-reactive protein (hsCRP) levels and to assess the presence of metabolic syndrome (MS) after puerperium in women diagnosed with various hypertensive disorders during pregnancy (HDP), a consecutive, cross-sectional case study at the 15th week after gestation. The sample consisted of 264 women who were admitted to a women's hospital. The diagnoses consisted of transient gestational hypertension (TGH=43.2%), preeclampsia (PC=29.5%), chronic hypertension (CH=20.1%) and PC superimposed on CH (7.2%). A diagnosis of previous hypertension was present in 45.8% of the CH group. The prevalence of MS was 16.7% (CH=42.1%, TGH=13.9%, PC=4.1%, P<0.001). The average hsCRP levels for the CH, TGH and PC groups were 3.79 ± 2.76, 3.55 ± 3.15 and 2.89 ± 3.02, respectively (P=0.040). The levels of hsCRP were higher in women with MS (4.71 ± 3.15 vs. 3.01 ± 2.88 mg l(-1) in those without MS, P<0.001), and they increased when a higher number of MS criteria was fulfilled (P<0.001). The results demonstrated a positive correlation between hsCRP levels and body mass index (BMI) (r=0.46), waist circumference (r=0.50) or the number of fulfilled MS criteria (r=0.56). The results suggest differences in vascular risk that depend on the type of HDP and on the prevalence of MS. The prevalence of MS was notably higher in the CH group, intermediate among the TGH group and much lower in the PC group. Differences in hsCRP levels also depended on the type of HDP (higher levels in CH and TGH patients in comparison with PC patients). Women with MS had higher hsCRP levels compared with women without MS, and the levels correlated with the number of MS criteria fulfilled. This result suggests that subclinical inflammatory status is correlated with the number of MS components present. Furthermore, hsCRP levels increased with increasing BMIs and waist circumferences.

G-protein beta-3 subunit gene C825 T polymorphism: influence on plasma sodium and potassium concentrations in essential hypertensive patients.

The C825T polymorphism of the beta-3 subunit of the protein G (GNB3) has been related to an increased activity of the Na+/H+ exchanger (NHE-1) through the synthesis of an anomalous hyperactive protein. Because of the important role of this system in essential hypertension (EH), we analysed the distribution of the different genotypes of this polymorphism in normotensive subjects (NS) and essential hypertensive patients (EHP), their relationship with the condition of salt sensitivity, plasma sodium and potassium concentrations and plasma renin activity (PRA) in EHP. 144 subjects (78 EHP and 76 NS) were studied. Salt sensitivity was assessed by the rapid protocol of Weinberger and genotype determination for GNB3 C825T polymorphism was performed by PCR. The distribution of the different genotypes was similar among EHP (CC 37.2%; CT 41.1%; TT 16.7%) and NS (CC 32.9%; CT 55.3%; TT 11.8%). In regard to general characteristics of EHP (including blood pressure levels) and the condition of salt sensitivity, there were no differences among the different genotypes. Plasma sodium concentration was higher and plasma potassium was lower in TT patients (141.0+/-1.7 and 3.7+/-0.1) than in CC patients (139.1+/-1.9 and 4.0+/-0.3) p<0.05. CT patients had intermediate values (139.9+/-1.9 and 3.9+/-0.2). PRA values were similar in the three genotypes as were the rest of analytical parameters studied. Our data demonstrate an association between the C825T polymorphism of the GNB3 and plasma sodium and potassium concentrations in EHP, as expression of an increase in NHE-1 activity, without modifications in PRA nor relationship with salt sensitivity.

[Glucose effectiveness and components of the metabolic syndrome in recently diagnosed hypertensive patients]. / Efectividad de la glucosa y componentes del síndrome metabólico en pacientes con hipertensión arterial esencial de diagnóstico reciente.

BACKGROUND: Glucose effectiveness (SG) is a parameter that indicates the glucose ability to clearing itself from the plasma independently of insulin's action. Our purpose was to analyze the cluster characteristics associated with the metabolic syndrome in a group of non-obese, recent-onset hypertensives and to test if there was a correlation with SG and the effectiveness of glucose at basal insulin point (GEZI). PATIENTS AND METHOD: We studied 36 patients with mild hypertension with normal basal glucose levels. We determined plasma lipid subfractions, apolipoproteins and urate levels. An intravenous glucose tolerance test (TTGI) and minimal model analysis according to Bergman was performed and SG, GEZI and insulin sensitivity (SI) were calculated. RESULTS: Patients with lower SG and GEZI had higher levels of total triglycerides (Tg) (r = 0.42; p = 0.01 and r = 0.48; p = 0.002, respectively) and triglycerides bind to VLDL (Tg-VLDL) (r = 0.40; p < 0.01 and r = 0.49; p = 0.002, respectively). When the cluster of metabolic syndrome was analyzed, SG was inversely related to uric acid levels and to the waist-hip index. However, SI was only related to the uric acid levels (r = 0.38; p = 0.01). CONCLUSIONS: In non-obese, recently diagnosed hypertensive patients, the SG parameter seems to be an early marker for the development of metabolic syndrome.