Plasma Kynurenine Predicts Severity and Complications of Heart Failure and Associates with Established Biochemical and Clinical Markers of Disease.

BACKGROUND: Kynurenine, a metabolite of the L-tryptophan pathway, plays a pivotal role in neuro-inflammation, cancer immunology, and cardiovascular inflammation, and has been shown to predict cardiovascular events. OBJECTIVES: It was our objective to increase the body of data regarding the value of kynurenine as a biomarker in chronic heart failure (CHF). METHODS: We investigated the predictive value of plasma kynurenine in a CHF cohort (CHF, n = 114); in a second cohort of defibrillator carriers with CHF (AICD, n = 156), we determined clinical and biochemical determinants of the marker which was measured by enzyme immunoassay. RESULTS: In the CHF cohort, both kynurenine and NT-proBNP increased with NYHA class. Univariate binary logistic regression showed kynurenine to predict death within a 6-month follow-up (OR 1.43, 95% CI 1.03-2.00, p = 0.033) whereas NT-proBNP did not contribute significantly. Kynurenine, like NT-proBNP, was able to discriminate at a 30% threshold of left ventricular ejection fraction (LVEF; AUC-ROC, both 0.74). Kynurenine correlated inversely with LVEF (ϱ = -0.394), glomerular filtration fraction (GFR; ϱ = -0.615), and peak VO2 (ϱ = -0.626). Moreover, there was a strong correlation of kynurenine with NT-proBNP (ϱ = 0.615). In the AICD cohort, multiple linear regression analysis demonstrated highly significant associations of kynurenine with GFR, hsCRP, and tryptophan, as well as a significant impact of age. CONCLUSIONS: This work speaks in favor of kynurenine being a new and valuable biomarker of CHF, with particular attention placed on its ability to predict mortality and reflect exercise capacity.

Relaxin-2 does not ameliorate nephropathy in an experimental model of type-1 diabetes.

BACKGROUND/AIMS: In diabetic nephropathy (DN), the current angiotensin-II-blocking pharmacotherapy is frequently failing. For diabetic cardiomyopathy (DC), there is no specific remedy available. Relaxin-2 (Rlx) - an anti-fibrotic, anti-inflammatory, and vasoprotecting peptide ­ is a candidate drug for both. METHODS: Low-dose (32 µg/kg/day) and high-dose (320 µg/kg/day) Rlx were tested against vehicle (n = 20 each) and non-diabetic controls (n = 14) for 12 weeks in a model of type-1 diabetes induced in endothelial nitric oxide synthase knock-out (eNOS-KO) mice by intraperitoneal injection of streptozotocin. RESULTS: Diabetic animals showed normal plasma creatinine, markedly increased albuminuria and urinary malonyldialdehyde, elevated relative kidney weight, glomerulosclerosis, and increased glomerular size, but no relevant interstitial fibrosis. Neither dose of Rlx affected these changes although the drug was active and targeted plasma levels were achieved. Of note, we found no activation of the renal TGF-ß pathway in this model. In the hearts of diabetic animals, no fibrotic alterations indicative of DC could be determined which precluded testing of the initial hypothesis. CONCLUSIONS: We investigated a model showing early DN without overt tubulointerstitial fibrosis and activation of the TGF-ß-Smad-2/3 pathway. In this model, Rlx proved ineffective; however, the same may not apply to other models and types of diabetes.

Comparison of a Point-Of-Care Test for High-Sensitivity C-Reactive Protein with an Established Immuno-Nephelometric Method.

BACKGROUND: High-sensitivity C-reactive protein (hsCRP) is an established marker of cardiovascular risk particularly in primary prevention. For years, it was exclusively measured using automated methods in clinical laboratories, but point-of-care tests (POCT) are urgently needed to simplify and hasten the determination of hsCRP. METHODS: This study compared a novel hsCRP POCT with an established nephelometric method in 104 patients showing a broad spectrum of cardiovascular risk. RESULTS: The results indicated a moderate agreement of the POCT with the standard method, with a sensitivity of 87% and a specificity of 80% to detect elevated hsCRP (> 1 mg/L). CONCLUSIONS: The minimization of sample volume appears to be the most promising strategy for future test improvement.

Biochemical Identification of Vitamin B12 Deficiency in a Medical Office.

BACKGROUND: A vitamin B12 deficiency can be an underlying cause or a deteriorating factor in several diseases. Nevertheless, early identification of such a deficiency remains a problem. Holotranscobalamin (HTC) is presently considered to be the gold standard. We tested the predictive power of other B12 parameters by comparing them with HTC. METHODS: The blood of 77 patients from a medical office was tested for HTC, total B12 (CLIA [chemiluminescent immunoassay] and MTP [microbiological test with microtitre plates]), MMA (methylmalonic acid), HCY (homocysteine), and MCV (mean cell volume). The parameters were correlated and sensitivity, specificity, PPV (positive predictive value), NPV (negative predictive value), LR+ (positive likelihood ratio), and LR- (negative likelihood ratio) in comparison to HTC were determined. A ROC analysis was also performed. RESULTS: At a cutoff value of 35 pmol/L for HTC, the total B12 CLIA (cutoff 211 ng/L) qualified 53% of individuals as having a B12 deficiency. The total B12 MTP (cutoff 288 ng/L) classified 71% as having a B12 deficiency. Specificity was similar in both cases (CLIA, 93%; MTP, 95%). With a cutoff value of 10 µmol/L for homocysteine, the best negative prediction was achieved. MVA has a low sensitivity (41%) and a high specificity (90%). Based on the ROC analysis, which indicated superiority of the B12-MTP, the reference levels of B12-CLIA and B12-MTP were raised to 304 and 368 ng/L, respectively. Thus, a probable B12 deficiency was identified in 94% of cases with either method and with a comparable specificity. CONCLUSIONS: If total B12 is applied to identify B12 deficiency, the cutoff values should be elevated to 304 (B12-CLIA) and 368 ng/L (B12-MTP) to improve the predictive power. The negative-predictive power of HCY can be useful in daily routine. HTC has a broad grey area of uncertainty and MMA should only be applied as a confirmatory test.

Comparison of a new microbiological assay with a standard high-performance liquid chromatographic method for determination of vitamin B6 in serum.

BACKGROUND: A high-performance liquid chromatographic (HPLC) assay for vitamin B6 in human serum was compared with a novel microbiological assay (ID-Vit) that uses microtitre plates precoated with a specific microorganism, thus avoiding numerous problems associated with the use of stock cultures utilized by common other microbial assay mit B6. METHODS: Data obtained using HPLC were compared with 1D-Vit results in 170 healthy individuals and in 68 patients with coronary artery disease (CAD, 37 with acute coronary syndrome [ACS], 31 with stable CAD). Regression and Bland-Altman analysis were performed. Homocysteine in CAD patients was measured by HPLC. RESULTS: The ID-Vit assay correlated well with the HPLC assay (Pearson's r = 0.89 [p < 0.0001] in healthy and 0.82 [p < 0.001] in CAD individuals). Bland-Altman analyses revealed good agreement between the results of both methods in both cohorts, with > or = 95% of all values grouping within the lines of agreement. In CAD patients, mean homocysteine values did not differ between stable CAD and ACS and were normal. Thirty-seven percent of CAD patients had estimated glomerular filtration rates (GFR) below 60 mL/min/1.73m2. GFR correlated inversely with homocysteine levels (r = -0.80, p < 0.001) whereas neither HPLC nor ID-Vit values for B6 did. CONCLUSIONS: ID-Vit assay and the HPLC standard are in very good agreement. The new assay can easily be automated and is less laborious than common microbiological assays. The lack of correlation between B6 vitamin and homocysteine can be accounted for by the fact that mean vitamin B6 in our CAD patients was in the normal range and that a relevant percentage of patients had chronic renal disease.

The influence of a whole food vegan diet with Nori algae and wild mushrooms on selected blood parameters.

BACKGROUND: Vegan and vegetarian diets could overcome many diseases of civilization. This study examines whether a whole food vegan diet with Nori algae and wild mushrooms can provide a sufficient quantity of critical nutrients. METHODS: Five blood samples (Baseline to Time 5) were taken over eight months from 75 subjects (10 vegans without B12 supplementation who consumed Nori algae and wild mushrooms, 20 vegans with supplementation, 40 vegetarians, 5 meat-eaters). Blood was analyzed for blood cell counts, total vitamin B12, holotranscobalamin, homocysteine, methylmalonic acid, vitamin B6, folic acid, ferritin, TSH, zinc, creatinine, vitamin D2 and D3. RESULTS: In the vegan group without supplementation, all means were within the tolerance (holotranscobalamin, homocystein) or normal, except for elevated methylmalonic acid and diminished vitamin D. This group developed significantly higher vitamin D2 levels. The vegan group with B12 supplementation and the vegetarian group showed normal values for all parameters. CONCLUSIONS: Vegans following a whole food diet had a borderline supply of vitamin B12. Folic acid, vitamin B6, TSH, iron metabolism, and the blood count were in the normal range. Vegans taking dietary supplements demonstrated satisfactory overall results. An ingestion of sundried mushrooms can contribute to the supply of vitamin D.

Bone sialoprotein stimulates cancer cell adhesion through the RGD motif and the αvß3 and αvß5 integrin receptors.

Being implicated in bone metastasis development, bone sialoprotein (BSP) expression is upregulated in patients with cancer. While BSP regulates cancer cell adhesion to the extracellular matrix, to the best of our knowledge, the specific adhesive molecular interactions in metastatic bone disease remain unclear. The present study aimed to improve the understanding of the arginine-glycine-aspartic acid (RGD) sequence of BSP and the integrin receptors αvß3 and αvß5 in BSP-mediated cancer cell adhesion. Human breast cancer (MDA-MB-231), prostate cancer (PC-3) and non-small cell lung cancer (NSCLC; NCI-H460) cell lines were cultured on BSP-coated plates. Adhesion assays with varying BSP concentrations were performed to evaluate the effect of exogenous glycine-arginine-glycine-aspartic acid-serine-proline (GRGDSP) peptide and anti-integrin antibodies on the attachment of cancer cells to BSP. Cell attachment was assessed using the alamarBlue® assay. The present results indicated that BSP supported the adhesion of cancer cells. The RGD counterpart GRGDSP peptide reduced the attachment of all tested cancer cell lines to BSP by ≤98.4%. Experiments with anti-integrin antibodies demonstrated differences among integrin receptors and cancer cell types. The αvß5 antibody decreased NSCLC cell adhesion to BSP by 84.3%, while the αvß3 antibody decreased adhesion by 14%. The αvß3 antibody decreased PC-3 cell adhesion to BSP by 46.4%, while the αvß5 antibody decreased adhesion by 9.5%. Adhesion of MDA-MB-231 cells to BSP was inhibited by 54.7% with αvß5 antibody. The present results demonstrated that BSP-induced cancer cell adhesion occurs through the binding of the RGD sequence of BSP to the cell integrin receptors αvß3 and αvß5. Differences between cancer types were found regarding the mediation via αvß3 or αvß5 receptors. The present findings may explain why certain cancer cells preferentially spread to the bone tissue, suggesting that targeting the RGD-integrin binding interaction could be a promising novel cancer treatment option.

Primary Sjögren's syndrome independently promotes premature subclinical atherosclerosis.

OBJECTIVES: Cardiovascular comorbidities are common in patients with autoimmune diseases. This study investigates the extent of subclinical atherosclerosis in patients with primary Sjögren's syndrome (pSS). Correlations with clinical factors such as organ involvement (OI) or disease activity were analysed and oxLDL antibodies (oxLDL ab) were measured as potential biomarkers of vascular damage. METHODS: Patients with pSS were consecutively included from the rheumatology outpatient clinic. Age- and sex-matched controls were recruited (2:1 ratio). Data collection was performed by a standardised questionnaire and Doppler ultrasound to evaluate the plaque extent and carotid intima-media thickness (cIMT). Propensity score matching included all cardiovascular risk (CVR) factors and corresponding laboratory markers. RESULTS: Data were available for 299 participants (199 pSS/100 controls), aged 59.4 years (50.6-65.0), 19.1% male. After matching, the pSS cohort had greater cIMT (p<0.001) and plaque extent (OR=1.82; 95% CI 1.14 to 2.95). Subgroup analyses of patients with pSS revealed that OI was associated with increased cIMT (p=0.025) and increased plaque occurrence compared with patients without OI (OR=1.74; 95% CI 1.02 to 3.01). OxLDL ab tended to be lower in patients with plaque (p=0.052). Correlations of higher Oxidized Low Density Lipoprotein (oxLDL) ab with EULAR Sjögren's Syndrome Disease Activity Index (p<0.001) and anti-Sjögren's-syndrome-related antigen A autoantibodies (SSA/Ro antibodies) (p=0.026) were observed. CONCLUSIONS: Subclinical atherosclerosis occurs earlier and more severely in patients with pSS. The difference in cIMT between pSS and controls seems mainly driven by patients with OI, suggesting that this subgroup is particularly at risk. OxLDL ab might protect against atherosclerotic progression in patients with pSS. CVR stratification and preventive medications such as Hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitors should be discussed and further longitudinal studies are needed.

Bone Sialoprotein Immobilized in Collagen Type I Enhances Angiogenesis In Vitro and In Ovo.

Bone fracture healing is a multistep process, including early immunological reactions, osteogenesis, and as a key factor, angiogenesis. Molecules inducing osteogenesis as well as angiogenesis are rare, but hold promise to be employed in bone tissue engineering. It has been demonstrated that the bone sialoprotein (BSP) can induce bone formation when immobilized in collagen type I, but its effect on angiogenesis still has to be characterized in detail. Therefore, the aim of this study was to analyse the effects of BSP immobilized in a collagen type I gel on angiogenesis. First, in vitro analyses with endothelial cells (HUVECs) were performed detecting enhancing effects of BSP on proliferation and gene expression of endothelial markers. A spheroid model was employed confirming these results. Finally, the inducing impact of BSP-collagen on vascular density was proved in a yolk sac membrane assay. Our results demonstrate that BSP is capable of inducing angiogenesis and confirm that collagen type I is the optimal carrier for this protein. Taking into account former results, and literature showing that BSP also induces osteogenesis, one can hypothesize that BSP couples angiogenesis and osteogenesis, making it a promising molecule to be used in bone tissue regeneration.

Vitamin D status from dried capillary blood samples.

BACKGROUND: Given the huge impact of vitamin D deficiency on a broad spectrum of diseases such as rickets, osteoporosis, mineral bone disease-vascular calcification syndrome, infectious diseases, but also several types of cancer and CNS diseases, reliable and simple methods to analyze the vitamin D status are urgently needed. METHODS: We developed an easy technique to determine the 25-OH vitamin D status from dried blood samples on filter paper. This allows determination of the 25-OH vitamin D status independently of venous blood taking, since only sampling of capillary blood is required for this new method. We compared the results of vitamin D measurements from venous blood of 96 healthy blood donors with those from capillary blood taken from the same patients at the same time. The capillary blood was dried on filter paper using the D-Vital ID dry-blood collection system. RESULTS: 25-OH vitamin D concentration data from extracted dried capillary blood filters correlated very well with data obtained after direct measurement of venous blood samples of the same blood donor (R: 0.7936; p < 0.0001). The correlation was linear over the whole range of 25-OH vitamin D concentrations seen in this study. A Bland-Altman plot revealed good agreement between both tests. CONCLUSIONS: The D-Vital ID dry-blood collection system showed an excellent performance as compared to the classical way of 25-OH vitamin D measurement from venous blood. This new technique will facilitate easy and reliable measurement for vitamin D status, in particular, in rural or isolated areas, developing countries, and field studies.

Bone Sialoprotein Immobilized in Collagen Type I Enhances Bone Regeneration In vitro and In vivo.

The use of bioactive molecules is a promising approach to enhance the bone healing properties of biomaterials. The aim of this study was to define the role of bone sialoprotein (BSP) immobilized in collagen type I in various settings. In vitro studies with human primary osteoblasts in mono- or in co-culture with endothelial cells demonstrated a slightly increased gene expression of osteogenic markers as well as an increased proliferation rate in osteoblasts after application of BSP immobilized in collagen type I. Two critical size bone defect models were used to analyze bone regeneration. BSP incorporated in collagen type I increased bone regeneration only marginally at one concentration in a calvarial defect model. To induce the mechanical stability, three-dimensional printing was used to produce a stable porous cylinder of polylactide. The cylinder was filled with collagen type I and immobilized BSP and implanted into a femoral defect of critical size in rats. This hybrid material was able to significantly induce bone regeneration. Our study clearly shows the osteogenic effect of BSP when combined with collagen type I as carrier and thereby offers various approaches and options for its use as bioactive molecule in bone substitute materials.

Measuring Vitamin D Status in Chronic Inflammatory Disorders: How does Chronic Inflammation Affect the Reliability of Vitamin D Metabolites in Patients with IBD?

Evidence gained from recent studies has generated increasing interest in the role of vitamin D in extraskeletal functions such as inflammation and immunoregulation. Although vitamin D deficiency has been implicated in the pathophysiology of inflammatory diseases including inflammatory bowel disease (IBD), evidence as to whether vitamin D supplementation may cure or prevent chronic disease is inconsistent. Since 25OH-vitamin D (25OHD) has been suggested to be an acute-phase protein, its utility as a vitamin D status marker is therefore questionable. In this study, possible interactions of vitamin D and inflammation were studied in 188 patients with IBD, with high-sensitivity C-reactive protein (hsCRP) levels ≥ 5 mg/dL and/or fecal calprotectin ≥ 250 µg/g defined as biochemical evidence of inflammatory activity. Levels of 25OHD and vitamin D-binding protein (VDBP) were determined by ELISA, and 1,25-dihydroxyvitamin D (1,25OHD) and dihydroxycholecalciferol (24,25OHD) by LC-MS/MS. Free and bioavailable vitamin D levels were calculated with the validated formula of Bikle. Serum 1,25OH2D and vitamin D binding protein (VDBP) levels were shown to differ between the inflammatory and noninflammatory groups: patients with inflammatory disease activity had significantly higher serum concentrations of 1,25OH2D (35.0 (16.4-67.3) vs. 18.5 (1.2-51.0) pg/mL, p < 0.001) and VDBP (351.2 (252.2-530.6) vs. 330.8 (183.5-560.3) mg/dL, p < 0.05) than patients without active inflammation. Serum 24,25OH2D levels were negatively correlated with erythrocyte sedimentation rate (ESR) (-0.155, p = 0.049) while concentrations of serum 1,25OH2D correlated positively with hsCRP (0.157, p = 0.036). Correlations with serum VDBP levels were found for ESR (0.150, p = 0.049), transferrin (0.160, p = 0.037) and hsCRP (0.261, p < 0.001). Levels of serum free and bioavailable 25OHD showed a negative correlation with ESR (-0.165, p = 0.031, -0.205, p < 0.001, respectively) and hsCRP (-0.164, p = 0.032, -0.208, p < 0.001 respectively), and a moderate negative correlation with fecal calprotectin (-0.377, p = 0.028, -0.409, p < 0.016, respectively). Serum total 25OHD concentration was the only vitamin D parameter found to have no specific correlation with any of the inflammatory markers. According to these results, the traditional parameter, total 25OHD, still appears to be the best marker of vitamin D status in patients with inflammatory bowel disease regardless of the presence of inflammation.

Serum Parathyroid Hormone Predicts Mortality in Coronary Angiography Patients with Type 2 Diabetes.

BACKGROUND: Elevated serum levels of parathyroid hormone (PTH), one of the main regulators of calcium homeostasis and vitamin D metabolism, have been proposed as predictors of mortality. The impact of type 2 diabetes mellitus (T2DM) on the putative association between PTH and mortality has not been investigated thus far. AIM: The aim of our study was to investigate the impact of T2DM on the power of PTH to predict mortality risk. METHODS: Serum PTH levels were determined in 904 consecutive Caucasian patients referred to coronary angiography for the evaluation of established or suspected stable coronary artery disease (CAD), including 235 patients with T2DM. Prospectively, deaths were recorded over a mean follow-up period of 6.3 years. RESULTS: PTH at baseline did not differ significantly between patients with and without T2DM (P = .307). Cox regression analysis revealed that the serum PTH level strongly predicted all-cause mortality in patients with T2DM (hazard ratio [HR] = 2.35 [1.37-4.03]; P = .002), whereas PTH did not predict all-cause mortality in patients without T2DM (HR = 1.04 [0.81-1.32]; P = .766). The interaction term PTH × T2DM was significant (P = .006), indicating a significantly stronger impact of PTH on mortality risk in patients with T2DM than in individuals without diabetes. The impact of PTH on mortality risk in patients with T2DM remained significant after adjustment for glycated hemoglobin A1c, diabetes duration, classical cardiovascular risk factors, serum levels of vitamin D, and kidney function (HR = 2.10 [1.10-4.10]; P = .030). CONCLUSION: We conclude that PTH is a significantly stronger predictor of all-cause mortality in patients with T2DM than in those without T2DM.

Autoantibodies against epidermal transglutaminase are a sensitive diagnostic marker in patients with dermatitis herpetiformis on a normal or gluten-free diet.

BACKGROUND: Dermatitis herpetiformis (DH) is a cutaneous manifestation of gluten-sensitive enteropathy (celiac disease). Patients with DH demonstrate circulating IgA antibodies against epidermal transglutaminase (eTG) and tissue transglutaminase (tTG). It has been suggested that eTG is the autoantigen of DH. OBJECTIVE: The purpose of this study was to characterize the autoimmune response to eTG and tTG in patients with DH on a normal or gluten-free diet (GFD). METHODS: Sera from 52 patients with DH were studied for the presence of IgA antibodies to eTG and tTG by enzyme-linked immunosorbant assay. In 38 patients, serum was obtained before initiation of a GFD, whereas 14 patients had been on a GFD for at least 2 years. RESULTS: Autoantibodies against eTG were detected in 36 of 38 patients (95%) and those against tTG in 30 of 38 patients (79%) with DH on a normal diet. Of 14 patients on a long-term GFD, 7 patients were free of DH lesions and did not require dapsone treatment. None of these patients showed circulating antibodies against eTG or tTG. The remaining 7 patients on a GFD were not able to stop taking dapsone. All these patients demonstrated anti-eTG antibodies, whereas only 3 of them showed additional reactivity against tTG. LIMITATION: Autoantibody levels against eTG and tTG before and after introduction of a GFD were not examined in the same patients. CONCLUSION: Our data suggest that antibodies to eTG are the most sensitive serologic marker in treated and untreated patients with DH and confirm the central role of eTG in the pathogenesis of this disease.

Differences in the results and interpretation of oxidized LDL cholesterol by two ELISA assays--an evaluation with samples from the PIOstat study.

BACKGROUND: The oxidized LDL-particles (oxLDL) are considered to be an important driving factor in the pathophysiology of arteriosclerosis. Few methods exist today to directly determine oxLDL in human plasma. We evaluated the plausibility of results derived from a new ELISA (Immundiagnostik, Bensheim, Germany) in comparison to a different ELISA test (Mercodia, Uppsala, Sweden). METHODS: Samples from a previous prospective, randomized study comparing the effects of pioglitazone with simvastatin on chronic systemic inflammation were measured at baseline and endpoint with both tests. Both drugs are known to have a decreasing effect on circulating small dense oxLDL levels. RESULTS: In total, 84 patients without diabetes mellitus were included into this analysis (45 female, 39 male, age(mean +/- SD): 58+/- 8 years). With the Mercodia ELISA, a decrease in oxLDL was seen with simvastatin only (Mean +/- SD: 54.2 +/- 12.5 U/L at baseline vs. 42.9 +/- 12.9 U/L at endpoint; p < 0.001, pioglitzone: 53.8 +/- 13.2 U/L vs. 54.3 +/- 15.254 U/L, n.s.). In contrast, a decrease of oxLDL was observed with the new ELISA for both drugs (simvastatin 65.1 +/- 21.8 ng/mL vs. 52.7 +/- 19.8 ng/mL; pioglitazone: 72.8 +/- 26.1 ng/ml vs. 57.9 +/- 22.1 ng/ml, p < 0.01 vs. baseline in both cases). CONCLUSION: Determination of oxLDL with the Mercodia method lead to lower results and detected only the changes with simvastatin. While statins decrease the overall number of oxLDL particles, pioglitazone predominantly changes the size and LDL composition leading to larger particles with lower oxidation. In our study, the Immundiagnostik ELISA but not the competitive method confirmed the expected efficacy of PPARgamma-activation in decreasing the oxidation of LDL particles.

Relaxin expression correlates significantly with serum changes in VEGF in response to antidiabetic treatment in male patients with type 2 diabetes mellitus.

Recent studies indicate that relaxin as well as VEGF possess cardioprotective properties. This study aimed to determine the association of relaxin with VEGF in patients with type 2 diabetes. We therefore analyzed samples from a recent study showing the benefits of anti-diabetic treatment on cardiovascular risk markers independently from glycemic control. VEGF, relaxin and markers of endothelial dysfunction, s-ICAM-1 and s-VCAM-1, were compared after 26 +/- 2 weeks of antidiabetic treatment with pioglitazone or glimepiride with their base line values. A total of 151 data sets (patients age, 62.7 +/- 8.1 years, diabetes duration, 6.8 +/- 6.6 years, 57 women, 94 men) were available for the analysis. Baseline values were in median, relaxin: 27.4 pg/mL 125% quartile 15.8; 75% quartile: 45.21, s-ICAM-1: 294 ng/mL [25% quartile: 260; 75% quartile: 331], s-VCAM-1: 677 ng/mL [25% quartile: 589; 75% quartile 871], VEGF: 350 pg/mL [25% quartile: 251; 75% quartile: 514]. Parameter variation after therapy showed a significant correlation of relaxin expression with VEGF expression (p = 0.02) in the entire study group. The correlation was seen in the subgroup of male patients (p < 0.01) but did not reach significance in the female patients (p = 0.71). No further correlation was observed analyzing the other investigated parameters. Our data suggest that relaxin may exert its cardioprotective action possibly via VEGF increase, particularly in men. In women, other pathways may superimpose this effect. In conclusion, our study supports the hypothesis of different regulating pathways and effects of relaxin in men and women also in patients with type 2 diabetes.

Effects of tilting and volume loading on plasma levels and urinary excretion of relaxin, NT-pro-ANP, and NT-pro-BNP in male volunteers.

The polypeptide relaxin (RLX) has been suggested to play a role in cardiorenal integration and to be related to the natriuretic peptide system. We hence examined the effects of variations in thoracic blood volume and intravenous volume loading on plasma and urinary RLX levels and associated changes in natriuretic peptide levels in healthy men. Two groups of eight subjects were randomly tilted into a 15 degrees feet-down or a 15 degrees head-down position. Ten volunteers were crossover subjected to an infusion of 15 ml/kg of 0.9% NaCl (over 60 min) or control during an observation period of 10 h. Blood and urine were sampled at timed intervals. RLX, NH(2)-terminal prohormones of atrial natriuretic peptide (NT-pro-ANP), and NH(2)-terminal prohormones of brain natriuretic peptide (NT-pro-BNP) were determined by enzyme, radio-, and electrochemoluminescence immunoassays, respectively. NT-pro-ANP levels (in percentage of baseline levels) were higher (P < 0.05) during the head-down (124 +/- 13%) than during the feet-down position (82 +/- 6%). NT-pro-BNP and RLX were not affected by tilting. Volume loading induced a short-lasting increase in plasma NT-pro-ANP, a delayed increase in plasma NT-pro-BNP, had no effect on plasma RLX, and induced a parallel increase in urine flow, renal excretion of sodium, RLX, and NT-pro-BNP. It is concluded that variations in thoracic blood volume in healthy men are not associated with variations in plasma RLX. Increased urinary RLX and NT-pro-BNP excretion during volume loading suggest renal production and a possible role of kidney-derived RLX and brain natriuretic peptide in sodium homeostasis in men.

The relationship between urotensin II plasma immunoreactivity and left ventricular filling pressures in coronary artery disease.

The role of urotensin II (U-II)--a vasoactive, mitogenic, and inotropic, peptide--in the pathophysiology of heart failure is controversial. The present study explores the relationship between plasma U-II immunoreactivity (U-IIIR) and hemodynamics in patients with coronary artery disease (CAD). Thirty-six patients with CAD-3 undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) and 36 medical patients (MED group) with CAD-1 to CAD-3 during right heart catheterization were studied. Significant correlations were observed between pulmonary capillary wedge pressure (PCWP) and U-IIIR--determined by enzyme immunoassay (EIA)--before (rho = 0.83) and after (rho = 0.6) cardiopulmonary bypass in the CABG group. With the exception of the CPB period, CABG patients with increased PCWP before CPB had higher U-II(IR) concentrations throughout the procedure. Significant correlations were observed between U-IIIR, proANP, proBNP, and mean right ventricular pressure (RVPM) in MED patients. No correlation was detectable between U-IIIR and PCWP. However, MED patients with CAD-3 (n = 13) had higher levels of U-IIIR, NTproANPIR (RIA), NTproBNPIR (EIA) and higher cardiac filling pressures than patients with CAD-1 (n = 13). These findings support an association between plasma U-IIIR levels and diastolic myocardial dysfunction in ischemic heart failure. The discrepancies regarding left and right cardiac filling pressures and U-IIIR levels in CABG and MED patients require further evaluation.

Plasma levels and cardiovascular gene expression of urotensin-II in human heart failure.

The peptide urotensin-II (U-II) has been described as most potent vasoconstrictor identified so far, but plasma values in humans and its role in cardiovascular pathophysiology are unknown. We investigated circulating urotensin-II and its potential role in human congestive heart failure (CHF). We enrolled control individuals (n=13; cardiac index [CI], 3.5+/-0.1 l/min/m2; pulmonary wedge pressure [PCWP], 10+/-1 mm Hg), patients with moderate (n=10; CI, 2.9+/-0.3 l/min/m2; PCWP, 14+/-2 mm Hg) and severe CHF (n=11; CI, 1.8+/-0.2 l/min/m2; PCWP, 33+/-2 mm Hg). Plasma levels of urotensin-II differed neither between controls, patients with moderate and severe CHF nor between different sites of measurement (pulmonary artery, left ventricle, coronary sinus, antecubital vein) within the single groups. Hemodynamic improvement by vasodilator therapy in severe CHF (CI, +78+/-3%; PCWP, -55+/-3%) did not affect circulating U-II over 24 h. Preprourotensin-II mRNA expression in right atria, left ventricles, mammary arteries and saphenous veins did not differ between controls with normal heart function and patients with end-stage CHF. In conclusion, urotensin-II plasma levels and its myocardial and vascular gene expression are unchanged in human CHF. Circulating urotensin-II does not respond to acute hemodynamic improvement. These findings suggest that urotensin-II does not play a major role in human CHF.

Are zinc levels in seminal plasma associated with seminal leukocytes and other determinants of semen quality?

OBJECTIVE: To evaluate a potential association of zinc levels with seminal leukocytes, the outcome of semen cultures; and semen quality and sperm fertilizing capacity. DESIGN: Prospective study. SETTING: Outpatient infertility clinic of a university hospital. PATIENT(S): Two hundred fifty-six randomly chosen asymptomatic males from subfertile couples. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Determination of zinc in seminal plasma by flame atomic absorption spectroscopy. In aliquots of the same ejaculates the following tests were performed: immunocytochemical round cell differentiation to determine leukocyte counts and ratios, microbial screening, and comprehensive evaluation of semen quality (sperm analysis, biochemical parameters, antisperm antibody testing, and in vitro examination of sperm ability to penetrate cervical mucus). The patients underwent medical history, clinical examination, and postcoital testing. Subsequent fertility was determined (controlled for female infertility factors). RESULT(S): The concentration of zinc in seminal plasma did not correlate in a statistically significant way with leukocytes in semen, nor was it associated with bacterial colonization. There was no statistically significant relationship of zinc in seminal plasma or serum with semen quality parameters nor with local antisperm antibody testing of the IgG or IgA class. Zinc levels did not influence sperm capacity to penetrate cervical mucus in vitro or in vivo, and did not affect subsequent fertility. CONCLUSION(S): The zinc level in seminal fluid and serum is not associated with silent male genital tract infection (indicated by seminal leukocytes); nor is it related to semen cultures in asymptomatic individuals. The lack of association with other semen quality parameters indicates that the routine determination of zinc levels during infertility investigation is not recommended.