Plasma apelin and ADMA Levels in patients with essential hypertension

Both apelin and asymetric dymethyl arginine (ADMA) regulate blood pressures. Low apelin and high ADMA levels have been reported in several cardiometabolic disorders. However, there is no data about ADMA and apelin levels in essential hypertension and any relationship between them. We investigated a group of newly diagnosed and untreated 30 young hypertensive men and 30 healthy controls. Apelin levels were significantly lower and the ADMA levels were significantly higher in the patients (p = 0.04 for both). Both ADMA and apelin were related to the systolic blood pressures (SBP) (beta = -0.393, p = 0.003; beta = 0.285, p = 0.03, respectively). Future studies are necessary in order to clearly define the role of ADMA and apelin in the pathogenesis of essential hypertension.

The effects of thyroxine replacement on the levels of serum asymmetric dimethylarginine (ADMA) and other biochemical cardiovascular risk markers in patients with subclinical hypothyroidism

BACKGROUND

The relationship between subclinical hypothyroidism (SH) and cardiovascular disease (CVD) is still under debate. The purpose of the present study was to evaluate plasma total homocysteine (tHcy), high sensitive C-reactive protein (hsCRP), small dense low-density lipoprotein (sdLDL), L-arginine and asymmetric dimethylarginine (ADMA) concentrations and their relationship to nitric oxide (NO) production, measured as plasma nitrite-plus-nitrate (NO(x)) concentration, in patients with SH before and after thyroxine replacement therapy and compared with control group values.

DESIGN

Eighty-four women with SH and 33 healthy women as controls matched to the patient group for sex, age and body mass index (BMI), were enrolled in this study. Lipoprotein profile, tHcy, hsCRP, sdLDL, ADMA, L-arginine and NO(x) were measured in pre- and post-treatment blood samples.

RESULTS

The pretreatment total cholesterol (TC), LDL-C, hsCRP, ADMA and L-arginine levels were significantly higher and NO(x) levels were lower than in the control group. After treatment, hsCRP, ADMA and L-arginine levels were significantly reduced and sdLDL and NO(x) levels were significantly increased.

CONCLUSION

The present study demonstrated an elevation of hsCRP and ADMA plasma levels of patients with SH associated with a reduction in NO production, which may contribute to some cardiovascular alterations. The elevated ADMA and hsCRP levels were reduced after thyroxine replacement. Also the sdLDL levels of SH patients were found to be lower than the control group values whereas TC and LDL were elevated. Even though we found an elevation in sdLDL levels after treatment, those values were still not higher than in the control group.

Decreased small dense LDL levels in Gilbert's syndrome

OBJECTIVE

To investigate the role of small dense low density lipoprotein cholesterol (sd-LDL-C) in the mechanism of decreased incidence of cardiovascular disease in Gilbert's syndrome (GS).

DESIGN AND METHODS

sd-LDL-C, ox-LDL, and high sensitive C reactive protein (hs-CRP) levels were investigated in subjects with GS (n=42) and compared to healthy controls (n=52).

RESULTS

Age, gender and body mass index (BMI) distributions were similar between the two groups. sd-LDL-C, ox-LDL and hs-CRP levels were lower in GS than the healthy controls (p<0.001, p<0.001 and p=0.001, respectively). Unconjugated bilirubin was negatively correlated with sd-LDL-C, ox-LDL and hs-CRP (r=-0.594, p<0.001; r=-0.249, p=0.016 and r=-0.373, p<0.001 respectively). In addition, sd-LDL-C was positively correlated with ox-LDL (r=0.307, p=0.003).

CONCLUSIONS

The findings of this preliminary study suggest that reduced sd-LDL-C, ox-LDL and hs-CRP levels may have a role in preventing atherosclerosis in subjects with GS.

Circulating vaspin and its relationship with insulin sensitivity, adiponectin, and liver histology in subjects with non-alcoholic steatohepatitis

OBJECTIVE

Non-alcoholic steatohepatitis (NASH) is closely associated with components of metabolic syndrome. Vaspin is a novel adipocytokine that may link obesity, insulin resistance (IR), and type 2 diabetes mellitus. We aimed to investigate circulating vaspin levels in subjects with NASH and also to search for the association of vaspin with IR, adiponectin, and histological findings.

MATERIAL AND METHODS

A total of 50 male patients with NASH and 30 healthy male controls were enrolled. Vaspin and adiponectin were measured with ELISA method. Insulin sensitivity determined by homeostasis model assessment (HOMA-IR) index.

RESULTS

Plasma vaspin levels were higher and adiponectin levels were lower in NASH group compared with controls (p < 0.01 and p < 0.001, respectively). However, in multivariate analysis adjusted for glucose and lipid parameters, and HOMA-IR indexes, the difference in vaspin concentrations was disappeared. Nonetheless, the difference regarding the adiponectin levels remained significant between groups (p = 0.03). Vaspin was negatively correlated with low-density lipoprotein cholesterol (r = -0.32, p = 0.03) in subjects with NASH.

CONCLUSIONS

This study indicates that circulating vaspin levels are not altered in male subjects with NASH. These results suggest that in the absence of metabolic risk factors, vaspin per se may not be involved in the pathogenesis of NASH.

Elevated urine neopterin levels in nonalcoholic steatohepatitis

OBJECTIVES

The aim of this study was to relate urine levels of neopterin, a marker of activation of the cellular immune system, with grading and staging of NASH.

DESIGN AND METHODS

Urine concentrations of neopterin, routine tests, insulin and C-peptide levels were assessed in 50 patients with NASH, 25 patients with chronic viral hepatitis (CVH), and in 26 healthy controls.

RESULTS

Urine neopterin levels were found elevated in the NASH and CVH groups compared with controls. There was no significant correlation between urine neopterin levels and inflammation grade in the liver.

CONCLUSIONS

Urine neopterin levels are a marker of cellular immunity and are higher in patients with NASH. However, neopterin levels were not significantly associated with histopathological grade and stage of disease.

Elevated serum neopterin levels in acetaminophen-induced liver injury

Neopterin is synthesized in macrophage/Kupffer cells by interferon-gamma and other cytokines. This study aimed to evaluate the utility of using neopterin as a biomarker of acetaminophen (APAP)-induced liver injury. Wistar rats, randomly divided into two groups (APAP and normal), received APAP (1.0 g/kg) and distilled water, respectively, by gastric tube. The APAP group had a higher degree of liver necrosis than the control group. The APAP group also had significantly higher serum neopterin levels than the normal group. Serum neopterin levels correlated with serum AST, ALT activities, and degree of necrosis. This study demonstrates the preclinical utility of neopterin as a biomarker for the animal model of APAP-induced liver injury. Further research studies are required to determine the preclinical opportunities of using neopterin as a marker of APAP-induced liver injury.

Pleural fluid and serum procalcitonin as diagnostic tools in tuberculous pleurisy

BACKGROUND

Diagnosis of tuberculous pleuritis is difficult because of its nonspecific clinical presentation and decreased efficiency of traditional diagnostic methods. We investigated the use of procalcitonin (PCT) concentration in tuberculous pleuritis diagnosis.

METHODS

A prospective clinical study was performed with two different patient groups. A total of 28 patients were included: 18 with tuberculosis and 10 with nontuberculous pleurisy. Serum and pleural fluid PCT concentrations were evaluated before treatment.

RESULTS

Serum and pleural fluid PCT concentrations were statistically different between tuberculous and nontuberculous pleurisy groups (P = 0.012 and P = 0.004, respectively), even though they were not elevated in relation to the cut-off level of 0.5 ng/mL. A positive and significant correlation was detected between serum and pleural fluid PCT levels (r = 0.49, P = 0.008). Diagnostic specificity and sensitivity values for serum and pleural fluid PCT in discriminating tuberculous from nontuberculous pleurisy were 80% and 72.2%, and 90% and 66.7% at the 0.081 and 0.113 ng/mL cut-off values, respectively.

CONCLUSION

Relative to the current cut-off level of 0.5 ng/mL, PCT concentration is not a useful parameter for the diagnosis of tuberculous pleurisy. Because there were PCT levels in patients with tuberculous pleurisy that were below the current cut-off level but were significantly different from those of the nontuberculous group, the use of PCT should be further investigated.

Relationship between hemoglobin and CD40 ligand in prediabetes

PURPOSE

Hemoglobin (Hb) regulates the endothelial function by modulating the bio-availability of NO at the tissue level. A significant direct relationship is present between the Hb levels and endothelial functions in patients with Type 2 diabetes. Testing whether this association also exists in subjects with prediabetes is important because prediabetes is associated with an increased risk of cardiovascular disease and mortality. Therefore, we investigated the association of Hb both with the classical cardiac risk factors and the markers for endothelial dysfunction and inflammation, in subjects with impaired glucose tolerance (IGT).

METHODS

We enrolled 69 normotensive, and cardiovascular events free subjects with IGT (M=40, age=45.50+/-6.8 yr). Plasma insulin, hsCRP, soluble CD40L, vonWillebrand factor, p-selectin levels were measured. The parameters given according to the higher and lower median Hb values of the subjects were compared.

RESULTS

Subjects with the higher Hb levels exhibited lower HDL-C (46.68+/-10.8 mg/dl vs 51.5+/-8.9 mg/dl; P=0.04) and higher systolic (122.57+/-6.2 mmHg vs 116.17+/-7.4 mmHg; p < 0.001) and diastolic (79.14+/-3.73 mmHg vs 75.58+/-6.1 mmHg; P=0.005) blood pressures and sCD40L (7.9+/-3.8 ng/ml vs 6.07+/-2.1 ng/ml; P=0.02) levels. Hb levels were correlated to the HDL cholesterol, sCD40L, systolic and diastolic blood pressures and waist circumference (r=-0.28, P=0.02; r=0.29, P=0.02; r=0.53, P < 0.001; r=0.41, P=0.001; r=0.42, P < 0.001 respectively). According to the multiple logistic regression analysis, Hb was the determinant of sCD40L levels (beta=0.437, P < 0.001).

CONCLUSION

These results indicate that there may be a link with higher Hb values and cardiovascular risk factors in patients with IGT. Further investigation is warranted to understand the clinical implications of these findings in subjects with prediabetes.

Gonadotropin treatment increases homocysteine levels in idiopathic hypogonadotropic hypogonadism: an indirect effect mediated by changes in body composition

The main objective of the present study was to examine the alterations in plasma total homocysteine (tHcy) concentrations during a testosterone-deficient state and after gonadotropin treatment for 6 Months in patients with idiopathic hypogonadotropic hypogonadism (IHH). Thirty-five newly diagnosed male patients with IHH (mean age 21.34+/-1.53 years) and 29 age- and body mass index-matched healthy males (mean age 21.52+/-1.77 years) were recruited into the study. Pretreatment levels of free testosterone (1.51+/-0.66 pg/ml), estradiol (21.37+/- 4.37 pg/ml), FSH (0.91+/-0.24 IU/l) and LH (1.25+/- 0.53 IU/l) were lower than controls (25.17+/-3.06 pg/ml, 31.00+/-4.96 pg/ml, 3.14+/-1.62 IU/l and 4.83+/-1.65 IU/l respectively) (P<0.001). They increased significantly after treatment (18.18+/-1.59 pg/ml, 27.97+/- 4.25 pg/ml, 2.41+/-0.27 IU/l and 2.79+/-0.19 IU/l respectively) (P<0.001). Patients with IHH had lower tHcy levels than controls (10.14+/-1.34 and 12.58+/- 2.29 micro mol/l respectively) (P<0.001). Plasma tHcy concentrations increased significantly (12.63+/-1.44 micromol/l) after 6 months of treatment (P<0.001). As compared with the controls, pretreatment levels of serum creatinine (63.54+/-13.01 vs 82.84+/-16.69 micromol/l), hemoglobin (12.98+/-0.56 vs 13.83+/-0.71 g/dl) and hematocrit (39.29+/-2.01 vs 41.38+/-1.95%) were significantly lower (P<0.001), and they increased significantly following treatment (80.24+/-11.93 micromol/l, 13.75+/-0.49 g/dl and 41.26+/-1.78% respectively) (P<0.001). The pretreatment folic acid and vitamin B(12) levels were significantly higher in patients when compared with controls (14.87+/-5.68 vs 12.52+/-4.98 nmol/l, P=0.034 and 289.75+/-92.34 vs 237.59+/-108.17 pmol/l, P=0.002 respectively). They decreased significantly after treatment (11.29+/-3.31 nmol/l and 228.51+/-54.33 pmol/l respectively) (P<0.001). The univariate and multivariate regression analysis results showed that only changes in creatinine, creatinine clearance, vitamin B12 and folic acid were independently associated with changes in tHcy levels in patients with IHH. In conclusion, the increase in plasma tHcy concentrations following gonadotropin treatment seems to be largely independent of changes in androgen levels.

Pressure-related Increase of Asymmetric Dimethylarginine Caused by Hyperbaric Oxygen in the Rat Brain: A Possible Neuroprotective Mechanism

A decrease in nitric oxide availability in the brain tissue due to the inhibition of nitric oxide synthase (NOS) activity during the early phases of hyperbaric oxygen (HBO) exposure was found to be involved in hyperoxic vasoconstriction leading to reduced regional cerebral blood flow. We hypothesized that the concentration of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase (NOS), may be an important factor during this hyperoxic vasoconstriction state. Rats were exposed to 1, 2 and 3 atmospheres pure oxygen for two hours. A fourth group of animals served as control. Asymmetric dimethylarginine, L-Arginine and nitrite/nitrate (NOx) concentrations were measured from deproteinized rat brain cytosols. In rat brains exposed to 3 atmospheres O2, ADMA and L-Arginine levels were found to be significantly higher and NOx significantly lower than control levels. Additionally, statistically significant correlations between ADMA and L-Arginine, and ADMA and NOx concentrations were detected. In conclusion, this is the first study indicating increased ADMA levels in rat brains exposed to HBO. The simultaneously decreased NOx values suggest that ADMA elevation resulted in NOS inhibition and therefore may be responsible for the early phase hyperoxic vasoconstriction.

Serum fetuin-A levels in postmenopausal women with osteoporosis

BACKGROUND/AIM

One of the functions of fetuin-A is the restriction of formation and expansion ofextraosseous hydroxyapatite crystals. TIhe exact correlation of fetuin-A with bone mineral density (BMD) has not been clearly elucidated yet. In this study, we aimed to assess the relationship between BMD and fetuin-A in postmenopausal women.

MATERIALS AND METHODS

Fifty postmenopausal women (25 with osteoporosis, 25 healthy controls) were included in the study. All participants were comparable for age and body mass index. None of the osteoporotic patients had received any medical treatment for osteoporosis. Serum fetuin-A levels were measured by ELISA method.

RESULTS

BMD scores of the groups were statistically significant (P < 0.001). Serum fetuin-A levels of the osteoporosis group were significantly lower compared to the control group (P = 0.009). Additionally, there was there was a mild to moderate positive correlation between fetuin-A and lumbar (r = 0.381, P = 0.06) and femoral (r = 0.143, P = 0.50) BMD in the osteoporotic group, though it did not reach statistical significance.

CONCLUSION

Decreased fetuin-A levels in women with postmenopausal osteoporosis suggest that fetuin-A may have a role in the development of osteoporosis. Further studies are required to define the exact role of fetuin-A in bone metabolism.

The effects of analytical factors on second trimester risk estimations

OBJECTIVE

Triple test with measured maternal serum alpha-fetoprotein, human chorionic gonadotropin, and unconjugated estriol combination as a routine procedure for fetal Down's syndrome, trisomy 18 and neural tube defect screening has some intrinsic problems, such as precision. The aim of this study was to evaluate the effect of analytical variation of triple test on prenatal risk estimation.

METHOD

Five different serum pools were prepared and triple test was performed seven times for within run and five times for between run precision determination.

RESULT

Within run and between run, precision values of risk estimations by measuring the same sample for Triple test were calculated to be 7.9-21.4% and 14.1-31.0% for trisomy 21, 13.2-23.7% and 14.2-15.1% for trisomy 18, 47.2 and 42.0 % for neural tube defect, respectively.

CONCLUSION

These results demonstrated that analytical variations have great impact on second trimester risk estimation procedures; therefore, triple test analyses should be carried out in laboratories using strict internal and external quality control programs. Moreover, triple test results should always be interpreted by considering analytical and biological variations.

Nebivolol therapy improves endothelial function and increases exercise tolerance in patients with cardiac syndrome X

OBJECTIVE

We sought to determine whether nebivolol affects coronary endothelial function and exercise induced ischemia in patients with cardiac syndrome X (CSX).

METHODS

The study protocol undertaken was based on a single-blind randomized controlled prospective study. After a 2-week washout period, 38 patients with cardiac syndrome X were randomized to receive either nebivolol 5 mg daily (n=19) or metoprolol 50 mg daily (n=19) in a single- blind design for 12 weeks. The control group under study was consisted of 16 age- and gender-matched subjects with negative treadmill exercise tests. Plasma endothelial nitric oxide (NOx), L-arginine, and asymmetric dimethylarginine (ADMA) were measured in all patients at baseline and after 12 weeks of treatment. Statistical differences among groups were tested by one-way analysis of variance and unpaired samples t test for parametric; Kruskal-Wallis and Mann-Whitney U tests for non-parametric variables, respectively. A paired samples t test was used to compare continuous variables before and after drug therapy.

RESULTS

At baseline, plasma level of NOx, L-arginine, and L-arginine/ADMA ratio were lower (p<0.001 for all) in patients with CSX than in the control patients. Whereas, the plasma ADMA levels were increased in the patient group (p<0.001). After 12 weeks of drug therapy, the patients taking nebivolol had increased levels of plasma NOx , plasma L-arginine, the L-arginine/ADMA ratio and decreased levels of plasma ADMA compared to those of the patients taking metoprolol (p<0.001). In addition, exercise duration to 1-mm ST depression and total exercise duration significantly increased after treatment in the nebivolol group compared to the metoprolol group (p<0.01). In the nebivolol group, Canadian Cardiovascular Society (CCS) angina classification improved by one or more categories in 12 (70%) patients, whereas it deteriorated or remained in the same category in 5 (30%) patients. Meanwhile, in the metoprolol group, the CCS angina classification improved by one or more categories in 7 (41%), whereas it deteriorated or remained in the same category in 10 (59%) patients.

CONCLUSION

Circulating endothelial function parameters (plasma ADMA, L-arginine, NOx levels) were impaired in patients with CSX. Nebivolol treatment was associated with better improvements in both circulating endothelial function and exercise stress test parameters than metoprolol. We believe that further studies are needed to evaluate the effects of nebivolol treatment on long-term clinical outcomes in patients with CSX.

Comparing the fatty acid levels of preterm and term breast milk in Turkish women

AIM

Lipids are the main source of calories and considered very important in infant growth. We aimed to compare fatty acid composition of term and preterm breast milk. This is the first study that compares the fatty acid levels of preterm and term breast milk in Turkish women.

MATERIALS AND METHODS

Breast milk samples were obtained from mothers of term (n = 15) and preterm (n = 15) infants on postnatal days 3, 7, and 28. Fatty acid composition of human breast milk was determined longitudinally by gas-chromatography/mass spectrometry.

RESULTS

There Were 31 fatty acids measured in the milk samples. In the first month, 17 fatty acid levels had significant differences. In group comparison, some fatty acids (C14:0, C16:0, C18:1 and C20:5) had significantly increased in the preterm group (P = 0.041, P = 0.046, P = 0.027, P = 0.033, respectively), whereas myristoleic acid (C14:1) and eicosanoic acid (C20:0) had significantly increased in the term group (P = 0.015, P = 0.048, respectively).

CONCLUSION

Term and preterm milk have different compositions of fatty acids. Breast milk composition changes over time. As a general conclusion, breast milk provides the lipid requirements of infants.