Effects of atorvastatin and simvastatin on oxidative stress in diet-induced hyperhomocysteinemia in Wistar albino rats: a comparative study.

Considering the well-known antioxidant properties of statins, it seems important to assess their impact on major markers of oxidative stress (superoxide anion radical, nitric oxide, and index of lipid peroxidation) to compare the antioxidative potentials of atorvastatin and simvastatin during the different degrees of hyperhomocysteinemia (HHcy) in rats. This study was conducted on adult male Wistar albino rats (n = 90; 4 weeks old; 100 ± 15 g body mass) in which HHcy was achieved by dietary manipulation. For 4 weeks, the animals were fed with one of the following diets: standard rodent chow, diet enriched in methionine with no deficiency in B vitamins (folic acid, B6, and B12), or diet enriched in methionine and deficient in B vitamins (folic acid, B6, and B12). At the same time, animals were treated with atorvastatin at doses of 3 mg/kg/day i.p. or simvastatin at doses of 5 mg/kg/day i.p. Levels of superoxide anion radical and TBARS were significantly decreased by administration of simvastatin in normal and high-homocysteine (Hcy) groups (p < 0.05). At 4 weeks after feeding with purified diets, the concentrations of the GSH, CAT, and SOD antioxidants were significantly affected among all groups (p < 0.05). Our results indicated that statin therapy had variable effects on the redox status in hyperhomocysteinemic rats, and simvastatin demonstrated stronger antioxidant effects than did atorvastatin.

Serum cystatin C levels in normal pregnancy.

AIM: The aim of this study was to determine the levels of cystatin C, creatinine and creatinine clearance in different trimesters of uncomplicated pregnancy in women with normal kidney function. SUBJECTS AND METHODS: A total of 109 pregnant women were included: group 1 - 38 women (average age 29.63 ± 4.3 y) in the first trimester, Group 2 - 32 women (average age 33.56 ± 5.95 y) in the second trimester and Group 3 - 39 pregnant women (average age 30.1 ± 6.95 y) in the third trimester. Serum cystatin C was determined by the PENIA method (Particle-Enhanced Nephelometric Immuno-Assay), using Behring tests (Behring Diagnostics GmbH, Marburg, Germany). Results were statistically analyzed using the ANOVA. RESULTS: A statistically significant increase in serum cystatin C level was found in the third trimester of pregnancy (0.69 ± 0.16 mg/l vs. 0.78 ± 0.26 mg/l vs. 1.21 ± 0.30 mg/l). CONCLUSION: It appears that cystatin C is not a reliable marker of kidney function in pregnancy and that its increase is connected with a combination of several factors, including endotheliasis, hormonal influence and glomerular filtration rate (GFR) alterations.

Increased total homocysteine level is associated with clinical status and severity of white matter changes in symptomatic patients with subcortical small vessel disease.

OBJECTIVE: Elevated plasma total homocysteine (tHcy) is an independent risk factor for ischemic stroke and has been linked to cerebral small vessel disease (SVD), in particular. Controversy persists as to whether increased tHcy is associated with functional status and cognitive decline in these patients. METHODS: Plasma tHcy, MTHFR polymorphism, vascular risk factors, functional and cognitive status and severity of lesions on MRI, assessed with the Age-Related White Matter Changes (ARWMC) visual grading scale, were analyzed in 95 patients with SVD and 41 healthy control subjects. RESULTS: Plasma tHcy levels were higher in patients with SVD (14.4±5.0 µmol/L) compared to healthy SVD-free controls (8.9±3.9 µmol/L). In SVD patients, tHcy levels strongly correlated with cognitive status (age-adjusted risk 5.8, 95% CI 1.3-25.3, p=0.015), functional status (age-adjusted risk 3.2, 95% CI 1.2-8.8, p=0.022) and severity of MRI lesions (age-adjusted risk 1.2, 95% CI 1.1-1.4; p=0.004). Only total ARWMC score was independently associated with increased tHcy levels (OR 1.2, 95%CI 1.1-1.4, p=0.004). Independent predictors of WMC occurrence were tHcy levels (OR 1.2, 95%CI 1.1-1.3, p=0.003) and mRS score (OR 2.2, 95%CI 1.2-4.1, p=0.017). CONCLUSIONS: In patients with cerebral SVD there is a positive association of increased plasma tHcy levels with clinical status and severity of WMC.

Firing duration of masseter motor units during prolonged low-level contractions.

OBJECTIVE: The study aimed to determine whether motor units (MUs) of the masseter muscle can be continuously active during a prolonged low-level sustained contraction. METHODS: Intramuscular fine-wire EMG activity was recorded unilaterally from the masseter muscles of 13 pain-free volunteers (mean age ± SD = 26.7 ± 7.7 years), during low-level biting tasks performed for 30 min. The stored intramuscular EMG signals were decomposed into individual MU action-potential trains using long-term decomposition software. Depending on relative duration of the MU activity, MUs were classified as sporadically (<50% of the time), intermittently (50% ≤ time ≤ 95%), or continuously active (>95% of the time). RESULTS: The overall number of MUs identified during the low-level biting task was 203. Of these, nine continuously active MUs (4.4%) were found in six of the 13 subjects investigated, whereas 50 intermittent MUs (24.6%) were found in 12 subjects. The remaining MUs (71.0%) were sporadically active and were found in all of the subjects investigated. CONCLUSION: The majority of masseter MUs is sporadically or intermittently active during prolonged low-level contractions, but some of them can also be continuously active. SIGNIFICANCE: Sustained clenching efforts may be accompanied by continuous activity of a few selected muscle fibres.

The importance of defining serum MMP-9 concentration in diabetics as an early marker of the rupture of atheromatous plaque in acute coronary syndrome.

Acute coronary syndrome (ACS) is the main cause of mortality in diabetics. Acute myocardial infarction (AMI) in diabetics is much more often than in non-diabetics. MMP-9 activity could ease the formation of atherosclerosis, destabilization and plaque rupture as well as thrombocyte aggregation. THE AIM OF THIS STUDY IS TO EXAMINE: MMP-9 defining in serum in diabetics; the impact of diabetes mellitus on atherosclerosis and MMP-9 level; relation between serum values of MMP-9 and markers of glycoregulation and lipid status, respectively. RESULTS: The greatest concentration of both total and active MMP-9 serum has been noted in diabetics group with ACS. Both total and active MMP-9 values, in group with diabetes and ACS showed significantly important difference regarding the values in control group. Total and active MMP-9 showed statistically important correlation between the values of glycated hemoglobine A1c (HbA1c) and inverse correlations with values of subfraction HDL3.Active MMP-9 showed statistically important inverse correlation with value of HDL cholesterol. IN CONCLUSION: According to the results, it has been thought that active MMP-9 shows a certain degree of atherosclerotic changes on blood vessels better than total MMP-9. MMP-9, active one, could present an early marker of atherosclerosis, especially on coronary blood vessels, in diabetics with type 2.