The Evaluation of Adropin and Autotaxin as Potential Markers of Endothelial Dysfunction in Preeclampsia.

Endothelial dysfunction (ED) plays a prominent role in the pathogenesis of preeclampsia (PE). There is a need for non-invasive methods to assess endothelial function in preeclamptic patients. In the present study, adropin, autotaxin (ATX), and lysophosphatidic acid (LPA) were evaluated as indicators of ED. Patients diagnosed with PE and healthy pregnant women (n = 42 for each group) were compared. After measuring flow-mediated dilation (FMD), the participants were stratified as ED (+) or ED (-) based on a cut-off value of 6.5%. The PE patients were divided as early/late onset PE and severe/mild PE. Adropin, ATX, and LPA levels were measured, and their relevance to ED was evaluated. Student t, Mann-Whitney U, or ANOVA tests were used for statistics, as appropriate. Adropin levels were diminished in the ED (+) group, whereas ATX and LPA levels were increased. The decrease in adropin levels was more pronounced in severe PE, showing a positive correlation with the FMD. In the logistic regression model, adropin was the only parameter that was an independent variable for the FMD test (P < .001). Adropin measurements in serum may be of value for disease follow-up in patients with PE.

Effects of betaine supplementation on nitric oxide metabolism, atherosclerotic parameters, and fatty liver in guinea pigs fed a high cholesterol plus methionine diet.

OBJECTIVE: The aim of this study was to investigate the effect of high cholesterol (CHOL) and CHOL + methionine (MET) diets on atherogenic and oxidative index parameters and on the factors that influence nitric oxide (NO) bioavailability. Also, attempts were made to determine whether dietary betaine (BET) resulted in any improvement in the changes that occurred after CHOL + MET administration. METHODS: Guinea pigs were fed chow containing 1.5% CHOL with or without 2% MET for 10 wk. A third group received the CHOL + MET + BET diet. Control groups were given standard chow or standard chow + BET. Arginine, NO, nitrotyrosine (NT), and asymmetric dimethylarginine (ADMA) levels; lipid profile; and dimethylarginine dimethylaminohydrolase (DDAH) activity were measured. The liver and aorta were subjected to histopathologic analysis. RESULTS: The CHOL + MET diet caused higher serum CHOL and homocysteine levels, but no further increases were seen in aortic CHOL and diene conjugate (DC) levels and histopathologic lesions as compared with the CHOL group. Hepatic lipids and DC levels were also higher, and histopathologic lesions were more severe. CHOL + MET feeding increased ADMA and NT levels as compared with those of the CHOL-fed group. When BET (1 g/kg body weight/d) was added to the CHOL + MET diet, homocysteine and lipid levels decreased and histopathologic changes were reversed. BET diet decreased serum ADMA and hepatic and aortic DC levels and partly restored DDAH activity. CONCLUSIONS: BET supplementation may be effective in preventing hyperlipidemia, disturbed NO availability, oxidative stress, and the development of fatty liver and atherosclerotic lesions that might result from excess amounts of cholesterol and methionine in the diet.

P-selectin, endocan, and some adhesion molecules in obese children and adolescents with non-alcoholic fatty liver disease.

There is increasing evidence for a direct relationship between the vascular system and non-alcoholic fatty liver disease (NAFLD). The aim of this study was to investigate endocan and adhesion molecules such as P-selectin derived from the endothelium and platelets in obese children and adolescents with NAFLD. One hundred obese patients and 40 lean controls were enrolled. The obese subjects were divided into two subgroups based on the presence or absence of fatty liver. Blood samples were assayed for endocan, P-selectin, platelet-derived growth factor (PDGF), intercellular cell adhesion molecule (ICAM)-1, and vascular cell adhesion molecule (VCAM)-1. Obese patients with NAFLD presented higher ALT and insulin levels, as well as more profound dyslipidemia when compared with their counterparts without NAFLD. Serum levels of high-sensitivity C-reactive protein, VCAM-1 and ICAM-1 were found increased in both obese groups, regardless of NAFLD. In obese subjects with NAFLD, decreased P-selectin levels (51.6 ± 4.14 ng/mL) were detected as compared with the obese (72.3 ± 4.23) and control (74.2 ± 6.97) subjects. Furthermore, circulating P-selectin levels were closely associated with endocan levels (r = 0.852, p < 0.001). Childhood obesity leads to vascular inflammation and therefore may cause a predisposition to atherosclerosis at an early age. The possible outcome of decreased P-selectin levels with NAFLD development must be further investigated.

Low concentrations of adropin are associated with endothelial dysfunction as assessed by flow-mediated dilatation in patients with metabolic syndrome.

BACKGROUND: In individuals with atherosclerotic risk factors, endothelial dysfunction (ED) appears as an early phase in the development of clinical symptoms. Recent studies indicate that adropin, a newly identified peptide, participates in cardiovascular health through the regulation of several metabolic events including angiogenesis and blood flow. In this study, we aimed to determine the relation of adropin with biochemical and radiologic parameters which reflect ED such as endothelial nitric oxide synthase (eNOS), endothelin 1 (ET-1), nitric oxide (NO) and flow-mediated dilatation (FMD) along with the routine biochemical measurements in patients recently diagnosed with metabolic syndrome (MetS). METHODS: Fasting blood samples from 110 patients with MetS diagnosed according to the NCEP ATP III-2005 criteria were collected to measure the concentrations of adropin and other parameters including the lipid profile, insulin and glucose. Serum NOx concentrations were determined by measuring NO2 plus NO3. FMD test was performed by ultrasonography, and patients were stratified as FMD (+) or (-). Data were compared between these two subgroups and also with matching healthy controls (n=50). Biochemical data were evaluated using Student's t or Mann-Whitney U tests. RESULTS: Fifty-nine subjects had ED (+) and the remaining 101 subjects were ED (-). In the first group, adropin levels were significantly lower than the latter (2.13±1.05 vs. 3.41±1.63 ng/mL, respectively; p<0.001) and independently associated with FMD positivity as assessed by the logistic regression analysis. CONCLUSIONS: Low adropin level in circulation is related to ED and has a close association with FMD. Any alterations in its level may be of help in order to assess the development of ED before the occurrence of clinical symptoms in patients with metabolic syndrome.

Hypovitaminosis D is Associated with Endothelial Dysfunction in Patients with Metabolic Syndrome.

OBJECTIVES: Recent research has shown that hypovitaminosis D may increase the risk of hypertension, vascular disease, diabetes mellitus, obesity and Metabolic Syndrome (MetS). Endothelial Dysfunction (ED) is one of the key components of MetS which is associated with an imbalance between vasoactive substances such as Nitric Oxide (NO) and Endothelins (ET). In this study, we assessed the association of 25(OH) D3 level with endothelial dysfunction and subclinical atherosclerosis in MetS patients. DESIGN AND METHODS: 105 MetS patients and 48 controls were included. 25(OH) D3 levels were measured using Ultra-High Performance Liquid Chromatography (UHPLC). NOx (NO2 plus NO3) and Endothelin- 1(ET-1) concentrations were determined along with routine biochemical tests. Flow-Mediated Dilatation (FMD) and carotid Intima-Media Thickness (cIMT) were measured by ultrasonography. RESULTS: In MetS patients, vitamin D and NOx levels were significantly lower (p<0.001), while ET-1 levels were higher than controls (p<0.005). MetS patients with ED exhibited significantly lower vitamin D levels than their counterparts free of ED. Vitamin D levels were correlated positively with FMD and NOx, and negatively with systolic blood pressure and body mass index. Subclinical atherosclerosis as assessed by the cIMT did not associate with low vitamin D levels. CONCLUSION: Vitamin D deficiency seen in MetS patients is more prominent in the presence of ED. Hypovitaminosis D may affect endothelial cells, and participate in the development of hypertension.

Effect of rosiglitazone on asymmetric dimethylarginine metabolism in thioacetamide-induced acute liver injury.

Asymmetric dimethylarginine (ADMA), an endogenous nitric oxide synthase inhibitor, is metabolized in the liver by dimethylarginine dimethylaminohydrolase (DDAH). We aimed to investigate the effect of rosiglitazone, a peroxysome proliferator-activated receptor-gamma (PPAR-γ) agonist, on ADMA metabolism in acute liver injury. Male Sprague Dawley rats were injected thioacetamide (TAA; 500mgkg(-1)) intraperitoneally in order to induce acute liver injury. ADMA, SDMA and arginine levels were determined in plasma by the HPLC. Liver DDAH activity and malondialdehyde (MDA) levels were measured by spectrophotometric procedures. TAA injection caused marked increases in ALT and AST activities. Plasma ADMA levels were increased, while arginine levels and arginine/ADMA ratio were decreased. Liver DDAH activity was significantly diminished and MDA levels were elevated. In another group of animals which were treated with a PPAR-γ agonist (rosiglitazone, 5mgkg(-1)) daily via gastric intubation for a week prior to TAA injection, significant recoveries in DDAH activity and antioxidant status were observed when compared with solely TAA-injected animals. Rosiglitazone pretreatment improved the plasma arginine/ADMA ratio. Our findings indicated that PPAR-γ agonist rosiglitazone beneficially influenced hepatic metabolism of ADMA in TAA-induced acute liver damage.

Platelet and other hemostatic characteristics in patients with chronic urticaria.

Several publications have pointed out the importance of coagulation and fibrinolysis in the occurrence of chronic urticaria (CU), but only a few indicated the direct role of platelets. We assessed platelet aggregation and evaluated parameters of coagulation and fibrinolysis in patients with CU. Patients (n = 34) diagnosed as having CU and 36 healthy controls were enrolled. Platelet aggregation was assayed using an impedance aggregometer and adenosine diphosphate, arachidonic acid, thrombin receptor-activating peptide (TRAP), and ristocetin as agonists. In patients with CU, significantly decreased platelet aggregation to some agonists (ristocetin and TRAP) was observed. The D-dimer levels were elevated, mean platelet volume was decreased, but no alteration was observed in other coagulation assays. Elevated D-dimer levels indicated that coagulation and fibrinolysis are activated in the patients with CU. Evaluation of platelet function may contribute to identify the role of these cells in the pathogenesis of CU.

Circulating levels of apelin, glucagon-like peptide and visfatin in hypercholesterolemic-hyperhomocysteinemic guinea-pigs: their relation with NO metabolism.

The aim of this study was to determine the levels of regulatory peptides apelin, glucagon-like peptide (GLP-1) and visfatin in hypercholesterolemic and hyperhomocysteinemic state and to examine their relation with nitric oxide (NO) metabolism. 32 Male guinea pigs were divided into four groups and each group was fed as follows: (a) commercial chow, (b) cholesterol (chol)-rich diet, (c) methionine (meth)-rich diet, and (d) chol + meth-rich diet. Blood samples were drawn at the end of 10 weeks, and abdominal aorta was dissected for histopathological examination. Serum insulin, GLP-1, apelin, visfatin, and nitrotyrosine concentrations were measured by the manufacturer's kits based on ELISA; asymmetric dimethylarginine (ADMA) and arginine levels were measured by the high performance liquid chromatography. Homocysteine level was measured by the chemiluminescence immunoassay; glucose, total chol and triglyceride levels were measured by the autoanalyzer. The microscopic examination of aorta indicated varying degrees of vascular disturbance in chol- and chol + meth-fed groups. High levels of chol and homocysteine, accompanied with significantly low levels of apelin and GLP-1 were detected in the plasma. Visfatin, ADMA, and nitrotyrosine levels both in chol- and chol + meth-fed groups were significantly higher than those in control animals, whereas arginine and arginine/ADMA ratio were lower. This study indicated that circulating levels of apelin, GLP-1, and visfatin are markedly altered during the development of atherosclerotic changes in close association with chol, homocysteine, NO, and ADMA levels. The measurements of these peptides in serum may help for the diagnosis and follow-up of vascular dysfunction.

Antidiabetic drug metformin is effective on the metabolism of asymmetric dimethylarginine in experimental liver injury.

AIMS: We aimed to investigate the pharmacological efficiency of metformin on asymmetric dimethylarginine (ADMA) metabolism in inflammation caused by the lipopolysaccharide (LPS)/D-galactosamine (D-GalN) treatment. METHODS: Adult Sprague-Dawley rats were injected LPS/D-GalN intraperitoneally. One half of the animals was injected metformin (250 mg kg(-1) body mass for one week) prior to LPS/D-GalN treatment. Six hours after the LPS/D-GalN injection, livers were removed, and used for the measurements of dimethylarginine dimethylaminohydrolase (DDAH) and myeloperoxidase (MPO) activities, glutathione (GSH), ADMA and arginine levels. Liver tissues were examined histopathologically. The Kruskal-Wallis (posthoc Mann-Whitney U) test was used for the statistics. LPS/D-GalN injections caused liver injury as evidenced by the activities of aminotransferases and arginase. GSH level and DDAH activity were decreased in the liver. Metformin pretreatment alleviated the activity of serum enzymes, and attenuated histopathological lesions caused by LPS/D-GalN injections. LPS/D-GalN-induced inflammation, as confirmed by the increased MPO activity, created an asymmetrical distribution of arginine and ADMA between the tissue and plasma. Metformin decreased tissue ADMA level while it restored the DDAH activity and GSH. CONCLUSION: Our findings showed that metformin administration for one week has a potency to protect liver through regulating ADMA metabolism in LPS/D-GalN-induced injury.

Propargylglycine aggravates liver damage in LPS-treated rats: Possible relation of nitrosative stress with the inhibition of H2S formation.

BACKGROUND: Hydrogen sulfide (H2S) is a naturally occurring gaseous transmitter, which may play important roles in normal physiology and disease. Here, we investigated the effect of endogenously formed H2S in the endotoxemic organ injury. METHODS: Male Wistar rats were subjected to acute endotoxemia [Escherichia coli lipopolysaccharide (LPS) 20 mg kg(-1), intraperitoneally (ip)]. A group of animals was injected d,l-propargylglycine (PAG, 50 mg kg(-1), ip), an inhibitor of the H2S-synthesizing enzyme cystathionine-γ-lyase (CSE), 60 min before LPS administration. Six hours after the LPS treatment, animals were sacrificed. Myeloperoxidase (MPO), dimethylarginine dimethylaminohydrolase (DDAH) activities and levels of nitrotyrosine and GSH were measured in the liver. Asymmetric dimethylarginine (ADMA) and arginine levels in both liver and plasma were determined using HPLC. RESULTS: LPS injections caused liver injury, as evidenced by the activities of serum aspartate aminotransferase and arginase. After LPS injections, increased arginine content and arginine/ADMA ratio were observed in the liver, together with significant decrements in both DDAH activity and GSH levels. Despite the accumulation of ADMA in the plasma, its level remained unchanged in the liver. PAG pretreatment aggravated the LPS-induced increase in the activities of MPO and serum enzymes. The most profound effect of PAG pretreatment was observed in nitrotyrosine levels in the liver, which were increased significantly as compared with the control and LPS-injected groups. CONCLUSION: These findings support the view that the suppression of nitrosative stress by endogenous H2S is one of the mechanisms to protect liver against endotoxemic injury.

Modulation of arginine and asymmetric dimethylarginine concentrations in liver and plasma by exogenous hydrogen sulfide in LPS-induced endotoxemia.

Plasma levels of asymmetric dimethylarginine (ADMA) are known to be elevated under pathological conditions, but reports on intracellular ADMA levels are scarce. In this study, we investigated whether lipopolysaccharide (LPS)-induced endotoxemia alters the intra- and extra-cellular partition of l-arginine and ADMA. The effect of H2S pretreatment was also researched. Wistar rats were given sodium hydrogen sulfide (NaHS, 1 mg·(kg body mass)(-1)) one hour before the LPS injections (20 mg·kg(-1)). Six hours after the LPS treatment, the animals were sacrificed. Myeloperoxidase (MPO) and dimethylarginine dimethylaminohydrolase (DDAH) activities and levels of hypoxia-inducible factor (HIF)-1α were measured in the liver. ADMA and arginine levels were determined using HPLC. LPS injection caused liver injury, as evidenced by the activities of alanine transaminase, aspartate transaminase, and arginase. LPS increased l-arginine content and decreased DDAH activity in the rat liver. MPO activity and HIF-1α levels indicated inflammation and hypoxia. Despite the accumulation of ADMA in the plasma, the level remained unchanged in the liver. NaHS pretreatment restored both the DDAH activity and intracellular l-arginine levels. It is concluded that increased H2S generation has a potency to restore hepatic l-arginine levels and ADMA handling in endotoxemia. Extra- and intra-cellular partitions of ADMA seem to depend on transport proteins as well as the DDAH activity.

The diagnostic role of human epididymis protein 4 and serum amyloid-A in early-stage endometrial cancer patients.

The aim of this study was to evaluate the prognostic and predictive efficacy of the human epididymis secretory protein 4 (HE4) and serum amyloid-A (S-AA) together with the other tumor markers (CA 125, CA 15-3, CEA, and CA 19-9) in endometrial cancer patients. The study group consisted of 64 patients with defined stage and grade of endometrial cancer and 60 women with benign uterine diseases. Thirty-four healthy women were defined as the control group. Fasting blood samples were collected prior to surgery and tumor marker levels were determined in blood samples by E170 autoanalyzer. S-AA concentrations were measured by particle-enhanced immunonephelometry. Preoperative serum HE4 and S-AA levels were significantly higher in endometrial cancer patients than in controls, whereas the other measured parameters were not significantly different. Serum levels of HE4 were related to both the stage and grade of tumor. The best cutoff point for HE4 was determined to be 59.7 pmol/L; with 75 % sensitivity and 65.5 % specificity. For S-AA, the cutoff point was 8.8 U/mL, with 68.7 % sensitivity and 58.6 % specificity. The combination of HE4, CA 125, CEA, and S-AA raised the sensitivity to 84 %. Preoperative measurement of serum HE4 and S-AA may be of help in early detection of endometrial cancer. Preoperative screening with these markers may provide important information about the patient's outcome and prognosis.

Curcumin prevents liver fat accumulation and serum fetuin-A increase in rats fed a high-fat diet.

Fetuin-A is synthesized in the liver and is secreted into the bloodstream. Clinical studies suggest involvement of fetuin-A in metabolic disorders such as visceral obesity, insulin resistance, diabetes, and fatty liver. Curcumin is extracted from the rhizome Curcuma longa and has been shown to possess potent antioxidant, anticarcinogenic, anti-inflammatory, and hypoglycemic properties. In this study, we investigated the effect of curcumin treatment on serum fetuin-A levels as well as hepatic lipids and prooxidant-antioxidant status in rats fed a high-fat diet (HFD). Male Sprague-Dawley rats were divided into six groups. Group 1 was fed control diet (10 % of total calories from fat). Groups 2 and 3 were given curcumin (100 and 400 mg/kg bw/day, respectively ) by gavage for 8 weeks and were fed control diet. Group 4 was fed with HFD (60 % of total calories from fat). Groups 5 and 6 received HFD together with the two doses of curcumin, respectively. Curcumin treatment appeared to be effective in reducing liver triglycerides and serum fetuin-A levels. These findings suggest that the reduction of fetuin-A may contribute to the beneficial effects of curcumin in the pathogenesis of obesity.

Evaluation of turbidimetric inhibition immunoassay (TINIA) and HPLC methods for glycated haemoglobin determination.

BACKGROUND: Various factors may affect the accuracy of hemoglobin (Hb) A1c measurements that are widely used to monitor glycemic control in diabetic patients. This study was aimed to compare the values of HbA1c obtained by two different methods, Roche Tina-quant second and thirdgeneration HbA1c assays based on the turbidimetric inhibition immunoassay (TINIA), and high-performance liquid chromatography (HPLC) cation-exchange method used by Arkray Adams HA-8160 analyzer. METHODS: Measurements of HbA1c were carried out in blood samples from 2,917 patients using above-mentioned methods. Linear regression was used for the correlation analysis and linear equations. Bland-Altman plots were performed from method comparison data using MedCalc statistical software. RESULTS: For the low control, the second generation Tina-quant assay had within-run and between-run CVs 0.8% and 0.9%; for the high control within-run and between-run CVs were 1% and 0.96%, respectively. HPLC method for the low control had within-run CV 1% and between-run CV 1.3%; for the high control within-run CV was 0.6% and between-run CV was 0.9%. CONCLUSION: There was a good concordance between the results of TINIA and HPLC methods (y = 1.091x - 0.363; r(2) = 0.96).

Bone turnover markers and vitamin D status in postmenopausal Turkish women.

The aim of this study was to examine some biochemical markers of bone metabolism such as C-telopeptide of type 1 collagen (CTx), procollagen I N-peptide (PINP), 25 hydroxy vitamin D [25(OH)D], parathormone (PTH), and alkaline phosphatase (total- and bone-ALP) in postmenopausal Turkish women, and to evaluate the influence of dietary factors on these parameters. This cross-sectional study comprised 70 postmenopausal and 25 premenopausal subjects from a similar socio-economical status. The postmenopausal group was further stratified with regard to vitamin plus calcium supplementation. A fasting blood sample was obtained for the biochemical analysis of bone markers. Ca, P, tALP, and CTx levels were significantly higher in postmenopausal women free of supplementation than those in premenopausal period; whereas 25(OH)D concentrations were below the reference value in both groups. Supplementations of vitamin and calcium resulted in significantly lower levels of PINP in the postmenopausal group (p = 0.017). A significant association was found between plasma 25(OH)D level and frequency of fish consumption. Dietary strategies to fortify calcium and vitamin D intake should be considered to decrease the complications due to D hypovitaminosis after the onset of menopause.

Association of the CC chemokine receptor 5 (CCR5) polymorphisms with preeclampsia in Turkish women.

AIM: Endothelial dysfunction and inflammation are involved in the pathogenesis of preeclampsia. The CC chemokine receptor 5 (CCR5) modulates inflammation secondary to endothelial dysfunction and related vascular disorders, by initiating chemotaxis. In this study, we examined the frequency of two polymorphisms, the CCR5D32 deletion and the CCR5-59029 A/G promoter point mutation in women with preeclampsia. METHODS: The CCR5 polymorphisms were genotyped in 74 preeclamptic and 128 controls who had been unaffected by preeclampsia in previous pregnancies. Genotyping was performed with the polymerase chain reaction and restriction fragment length polymorphism. Statistical evaluations were made using the chi-square test or Fisher's exact test when appropriate. RESULTS: The percentage of wild-type allele bearers (?/?plus ?/D32 genotypes) in the preeclamptic group was significantly higher than that of non-bearers (98.6 vs.91.4%, P = 0.03, by the Fisher's exact test). The number of the individuals with D32/D32 genotype was significantly high in the control group (P = 0.035). D32 allele revealed a 2.3-fold protective effect against the risk of preeclampsia.When the percentage of G allele bearers of CCR5 59029A/G polymorphism was compared between the groups, a significant increase was seen in preeclamptics (P = 0.002). CONCLUSION: CCR5 polymorphisms significantly influenced the susceptibility to preeclampsia in our study population consisted of Caucasians. The role of chemokines in this syndrome appears to be an important issue.

-765 G→C and -1195 A→G promoter variants of the cyclooxygenase-2 gene decrease the risk for preeclampsia.

Cyclooxygenase-2 (COX-2) is the inducible isoenzyme of COX that leads to increased production of prostaglandins and thromboxane, the mediators of inflammation. Controversial data regarding COX levels or activities in the placentas of women with preeclampsia have led us to examine whether a single nucleotide polymorphism (SNP) in the COX-2 gene is associated with the onset of preeclampsia. Two polymorphisms in the promoter region of COX-2 gene were examined by the polymerase chain reaction and restriction fragment length polymorphism in 128 controls and 74 preeclamptic patients. Genotype distribution and allelic frequencies for -765G→C polymorphism of COX-2 gene were significantly different between patients and controls (p=0.000 and p=0.042, respectively). The odds ratio (OR) for preeclampsia risk associated to the -765G allelic variant was 4.07 (95% confidence interval [CI]: 0.89-18.56). The AA genotype of the -1195 A→G variant was present at a significantly higher frequency among all preeclamptic subjects (p=0.000 χ(2): 13.4, OR: 3.44, 95% CI: 1.74-6.77). A moderate linkage was observed between the -765G and -1195A variants (D(0): 0.201; r(2): 0.003). These findings suggest that SNPs, -765G→C and -1195 A→G, on the promoter region of COX-2 gene may reduce the risk of preeclampsia, possibly by affecting the rate of gene expression.

Dimethylarginines in patients with type 2 diabetes mellitus: relation with the glycaemic control.

We tested the relationship between plasma levels of dimethylarginines (ADMA and SDMA) and glycaemic control in 43 type 2 diabetic patients. Type 2 diabetics with poor glycaemic control (HbA1c>6.5) had significantly lower SDMA and higher ADMA concentrations than those with well-controlled glycaemia (HbA1c<6.5).