In recent years significant overlap between cardio-metabolic risk factors and cognitive decline has been reported. Cardio-metabolic and vascular factors shown to be associated with Alzheimer’s disease (AD) and other forms of dementia include midlife diabetes and hypertension, cerebrovascular lesions, diminished vascular function, dyslipidemia, obesity, and cigarette smoking. Accordingly, it has been recently proposed that amyloid is not the cause of AD but merely a marker and a later consequence of upstream changes that lead to neuronal and synaptic losses. However, although the idea that features of vascular dysfunction and injury are present in cognitive decline and AD patients was suggested over 25 years ago, the role of cardio-metabolic and cerebrovascular mechanisms in the pathogenesis of AD is far from being fully elucidated. Based on newly proposed vascular hypothesis, there is an impaired structure and function of cerebral blood vessels and cells in patients with cognitive decline and AD which is mediated by vascular oxidative stress. Consistent with these observations, the importance of endothelial dysfunction in the development of AD has been highlighted. One of the most prominent features of endothelial dysfunction is decreased production and bioavailability of Nitric Oxide (NO). Based on versatile properties in physiological as well as in pathophysiological conditions NO is regarded as a key molecule for longevity and cardiovascular health. NO is produced by three different isoforms of the enzyme NO synthase (NOS), namely: endothelial (eNOS), neuronal (nNOS), and inducible (iNOS). Reduced NO bioavailability and altered vascular expression and activity of NOS enzymes are implicated as major molecular players in the process of vascular aging. In the process of aging, the mechanisms by which NOS enzymes promote vascular dysfunction are specific for each NOS isoform. Normal activity of eNOS is required for the balanced production/bioavailability of NO, which is the main prerequisite for optimal vascular function. Conversely, excessive amount of NO produced by iNOS contributes to vascular dysfunction. Furthermore, although the possible role of nNOS-derived NO in aging-associated vascular dysfunction is far from being fully elucidated, experimental findings indicate that impaired perivascular NO release from nNOS increases vasoconstriction in aged arterioles. Oxidative stress and inhibitors of NO synthase are regarded as most potent initiators of disturbed production and bioavailability of NO. Important endogenous inhibitor of all three isoforms of NOS is asymmetrical dimethylarginine (ADMA). It has been recently proposed that ADMA may be a possible link between vascular disease and dementia. Based on this assumption ADMA might represent a unifying pathophysiological pathway linking the presence of vascular risk factors with the onset and progression of cognitive decline and dementia. These observations were made based on good evidence from literature that higher plasma ADMA concentrations favor atherosclerosis and independently predict adverse cardiovascular and cerebrovascular outcomes in several patient groups. However, possible role of ADMA in pathophysiology of cognitive decline and AD is still not fully understood. Prospective studies are warranted aiming at further clarification of ADMA involvement in development and progression of dementia. Moreover, use of ADMA in CSF and /or plasma as prospective biomarker of AD should be explored. According to newly introduced hypothesis disturbed NOS-NO-ADMA pathway is one of the most important attributes of cerebrovascular dysfunction that plays a pathogenic role in the development of cognitive decline and dementia. Experimental data from cell cultures and animal models have demonstrated that dysfunction of the NO-NOS- ADMA pathway results in cell death, blood-brain barrier (BBB) disruption, and brain edema via different pathological mechanisms. However, exact underlining mechanisms through which disturbed NOS-NO-ADMA pathway contributes to cognitive decline and dementia remain to be elucidated. Clarification of these mechanisms may be helpful in the identification of new therapeutic targets for aging and neurodegenerative diseases. Future research should also explain whether endothelial dysfunction precede or follow neurological changes which characterize cognitive decline and dementia. Moreover, clinical and epidemiological studies have shown that healthy nutrition and physical exercise are important non-pharmacological, lifestyle-related interventions that could help in maintaining appropriate vascular tone, adequate cerebral blood flow and normal cognition during aging. It is reasonable to suggest that prevention of cardio-metabolic diseases via endorsement of healthy aging determinants such as control of blood pressure, lipids and glucose levels as well as maintenance of optimal body weight achieved by regular physical activity and nutrition with high anti-oxidant capacity might be effective strategy in the preservation of cognitive function.

Objectives: Aim of the present study was to investigate serum concentration of leptin and its association with values of body mass index (BMI), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) in hemodialysis (HD) patients. Methods: This cross-sectional study included 60 HD patients (34 male, 26 female) and 30 age- and sex-matched (4 males, 26 females) apparently healthy subjects. Serum leptin concentration was determined by an enzyme-linked immunosorbent assay (ELISA). Serum CRP concentration was measured by means of particle-enhanced immunonephelometry. ESR value was determined by Western Green method. BMI was calculated as weight (kg) divided by height squared (m2). Results: Results have shown that median serum leptin concentration (30.65 ng/mL; 12.48-86.40 ng/mL) was statistically significantly higher in HD patients compared to median serum leptin concentration (15.75 ng/mL; 9.15-30.65 ng/mL) in the control group of healthy subjects (p<0.05). Likewise, median serum CRP concentration (5.5 mg/L; 1.93-8.9 mg/L) and median ESR value (57.5 mm/h; 40.5-77.0 mm/h) were significantly higher in HD patients compared to median serum CRP concentration (0.8 mg/L; 0.38-1.43 mg/L) (p<0.001) and median ESR value (10.0 mm/h; 6.5-14.0 mm/h) (p<0.001) determined in the control group. Statistically significant positive correlation was found between BMI values and serum leptin concentration in HD patients (rho=0.434; p<0.001). Positive, although not significant, correlation was observed between serum CRP and leptin levels in HD patients (rho=0.171; p>0.05). Negative correlation between ESR values and serum leptin concentrations in HD patients was determined but it was not statistically significant (rho= -0.029; p>0.05). Conclusions: Increased serum concentration of leptin as pro-inflammatory cytokine as well as elevated serum values of CRP and ESR indicate presence of systemic micro inflammation in HD patients. Results of the present study point to possible use of serum leptin concentration as an indicator of nutritional status in HD patients based on observed significant positive correlation between serum leptin concentrations and BMI values. However, absence of significant association between serum leptin and CRP levels as well as between serum leptin concentrations and ESR values in HD patients requires further investigation and clarification.

Objectives : Alternations in adipokines secretion associated with obesity could play an important role in diet-induced diabetes. The aim of our study was to estimate the impact of high-fat diet on serum adiponectin and leptin levels in streptozotocin (STZ) induced type 2 diabetes mellitus (T2DM). Methods : The study included 40 adult male Wistar rats were divided into four groups: Standard food control group (C-Non-HF)(n=10), standard food STZ group (STZ-NonHF)(n=10), high-fat diet control group (C-HF)(n =10) and high-fat diet STZ group (STZ-HF)(n =10). C-NonHF and STZ-NonHF group was fed with regular chow, and other two groups were given high-fat diet for 5 weeks. Type 2 DM was induced by single intra-peritoneal STZ injection (60 mg/kg). All the rats were fasted for 12 hours; when blood samples were taken for the measurement of serum leptin and adiponectin level by ELISA. Results : Mean serum adiponectin level was significantly lower in STZ-HF (1.34±0.57 ng/mL) compared to STZ-NonHF (2.61±0.79 ng/mL), C-NonHF (3.13±0.74 ng/mL) and C-HF group (3.04±0.63 ng/mL) (p<0.01). Mean serum leptin level was significantly higher in STZ-HF (1792.0}1378.8 pg/mL) compared to STZ-NonHF (634.0}149.1 pg/mL), C-NonHF (671.5}164.0 pg/mL) and C-HF group (593.8}200.8 pg/mL) (p<0.05). In STZ-HF group, a significant positive correlation between leptin and glucose level was observed (r=0.71; p=0.048). Conclusion : Our study results show that high fat diet induces an increase in serum leptin and the decrease in adiponectin levels in STZ diabetic rats and suggests that high fat diet impairs glucose control by increasing leptin secretion. Key words: Diabetes mellitus, leptin, adiponectin, obesity

Aim: To investigate the capacity of mean platelet volume (MPV) in detecting CD disease activity and in differentiating CD patients from healthy controls. Methods : MPV values were measured in 30 CD patients and 30 healthy individuals matched for age and gender. Based on the result of Crohn’s Disease Activity Index, CD patients were subdivided into two subgroups: active and inactive phase of disease. MPV was measured by standard methods for all study participants. Results: A significant decrease in MPV was noted in CD patients compared to healthy controls (p=0.002). When active CD patients were compared with inactive CD patients, a  significant decrease in MPV was also found (p=0.031). The overall accuracy of MPV in discriminating CD patients from healthy controls as well as active from inactive CD patients was 66% (cut-off level of 8.83 fL). Significant negative correlation between MPV and platelet count (PLT) (rho= -0.570; p=0.01) and significant positive correlation between MPV and platelet distribution width (PDW) (rho= 0.615; p=0.01) was observed in CD patients. Conclusion: Based on our results that have shown significant difference in MPV that was related to Crohn’s disease activity, we consider that MPV could be added to other serological markers of CD, especially in differentiating the active from the inactive phase of disease. Key words: mean platelet volume, Crohn’s disease, inflammatory bowel disease

The aim was to examine the predictive value of two different equations for glomerular filtration rate (GFR) assessment: Cockcroft-Gault (CG) and modification of diet in renal disease (MDRD) in patients with chronic kidney diseases(CKD). We also aimed to compare sensitivity and specificityof the predictive equations in renal function assessment. Thestudy included 75 patients with CKD who were further dividedinto four groups according to the stages of disease (CKDStage 1-4) and 25 healthy subjects. The GFR was estimatedusing CG and MDRD equations. The estimated GFR valuesusing the MDRD equation in all groups were lower comparedto those calculated using the CG equation. In patientswith CKD stage 1, GFR was significantly lower as estimatedby MDRD compared to CG equation (p=0.032). The ROC curves for estimated GFR using CG and MDRD equations in CKD patients vs healthy subjects were significant (AUC for CG 0.839 and for MDRD 0.923; p<0.0005). The optimal cutoff value for GFR estimated by CG equation was 62.86 mL/min (sensitivity 81.25%; specificity 76%) and for estimated GFR using MDRD equation 57.2 mL/min/1.73° m2 (sensitivity91.3%; specificity 81%). MDRD equation yields higher sensitivity and specificity in predicting GFR in patients with CKD compared to CG equation. Key words: chronic kidney disease, glomerular filtration rate, Cockcroft-Gault equation, modification of diet in renal disease (MDRD) study equation

The aim of this study was to investigate changes in serum nitric oxide (NO) concentration in inflammatory bowel diseases (IBD) patients and its use as potential biomarker in differential diagnosis of ulcerative colitis (UC) and Crohn's disease (CD) and in disease activity assessment. In 60 patients of both genders - 30 with ulcerative colitis and 30 with Crohn's disease - and 30 controls serum nitric oxide concentration was determined by measuring nitrite concentration, a stable metabolic product of NO with oxygen. Conversion of nitrates (NO3-) to nitrites (NO2-) was done with elementary zinc. The nitrite concentration was determined by classic colorimetrical Griess reaction. Median serum NO concentration was statistically different (p=0,0005) between UC patients (15.25 µmol/L; 13.47 - 19.88 µmol/L), CD patients (14.54 µmol/L; 13.03 -16.32 µmol/L) and healthy controls (13.29 µmol/L; 12.40 - 13.92 µmol/L). When active UC and CD patients were compared with inactive UC and CD patients respectively a significant difference in serum NO level was found (p=0.0005). With a cut-off level of 17.39 µmol/L NO had a sensitivity of 100% and a specificity of 100% in discriminating between active and inactive UC patients. With cut-off value of 14.01 µmol/L serum NO level had a sensitivity of 88% and a specificity of 69% in distinguishing between patients with active CD and inactive CD. Serum NO concentration is a minimally invasive and rapid tool for discriminating between active and inactive IBD patients and could be used as useful biomarker in monitoring of disease activity in IBD patients.

Autoimmune diseases occur in 3−5% of the population. Study included 30 patients with clinically diagnosed SLE and 30 healthy controls (American college of Rheumatology, 1997). SLE was diagnosed according to criteria issued in 1997 by the American College of Rheumatology (ACR). The aim of this study was to evaluate concentration values of each antigen of ENA-6 profile in SLE, to investigate possible correlation between the concentration of Sm antibodies and CIC, and to test their use as possible immunobiological markers in SLE. Furthermore, the aim of our study was to determine whether there is a correlation between Sm antibodies and CIC and SLE activity. The results revealed that all of these ENA-6 and Sm antibodies as biomarkers complement diagnoses of active SLE but their use as solo markers does not allow classifying patients with SLE. Our study has shown that based on calculations from ROC curves, Sm/RNP was clearly a very important marker for diagnosis of SLE (cut off ≥ 9.56 EU, AUC 0,942). The high incidence of Scl-70 (10%) reactivity suggests that ELISA monitoring of this antibody produces more false positive results than other multiplex assay. An important conclusion that can be drawn from the results of our study is that laboratory tests are no more effective than clinical examination for detecting disease relapse, but are helpful in the confirmation of SLE activity.

Cardiovascular diseases (CVD) remain a major burden for public health worldwide. Pivotal concern of primary prevention is identification of individuals that are at risk for developing cardiovascular disease. The use of different algorithms for an assessment of cardiovascular risk allows physicians to identify and treat in a simple and cost-effective manner individuals that may be at high long-term cardiovascular risk.

This study investigated whether serum C-reactive protein (CRP) concentration is increased in patients with type 1 diabetes mellitus with a normal body mass index (BMI) and whether BMI, glycated haemoglobin (HbA1c) and CRP are correlated in patients with type 1 diabetes. High-sensitivity CRP was determined by immunonephelometry and HbA1c by an immunoturbidimetric method in 30 patients with type 1 diabetes and 30 healthy individuals matched for age, sex and BMI. Median serum CRP concentration in patients with type 1 diabetes (1.34 mg/L) was significantly higher than healthy individuals (0.2 mg/L; p<0.0001). Positive correlation between CRP and BMI was observed (rho=0.598; p<0.0001), but no significant correlation was observed between CRP and HbA1c (rho=0.285; p=NS) in patients with type 1 diabetes. Increased CRP levels in type 1 diabetes patients do not appear to be associated with glycaemic control, and may reflect low-grade inflammation associated with atherosclerosis, as well as activation of innate immune activity. Br J Diabetes Vasc Dis 2011;11:249-252

AIM To estimate the effects of forced repeated swimming stress on BNP serum levels in rats. METHODS Adult male Wistar rats weighting between 280-330 g were divided into two groups: control group (n = 8) and stress group (n = 8). Rats in the stress group were exposed to forced swimming stress daily, for 7 days. The rats were forced to swim in plastic tanks (90 cm wide, 120 cm deep) containing tap water (temperature ca. 25 degrees C). The depth of water was 40 cm. Duration of each swimming session progressively increased from 10 minutes on the first day to 40 minutes on days 6 and 7. Rats were sacrificed and blood was drawn from abdominal aorta for BNP analysis immediately after the last swimming session. B-type natriuretic serum level was determined by ELISA method using RAT BNP-32 kit (Phoenix Pharmaceutical Inc.). RESULTS There was no statistically significant difference between mean BNP serum level in the stress group after the swimming period (0.81 +/- 0.14 ng/ml) as compared to the unstressed group of rats (0.8 +/- 0.08 ng/ml). After the swimming period mean body weight slightly decreased in the stress group in comparison with values before stress period (296.3 g vs. 272.8 g), but this difference was not statistically significant. The stress period had no influence on food intake in the stress rat group. CONCLUSION The workload consisting of 40-minutes long swimming session is not sufficient to provoke BNP release from myocardium in rats.

Aim: Nitric oxide is involved in pathological processes that lead to tissue damage partly because of its free radical nature. Oxidative stress and vascular dysfunction are recognized contributors in the pathogenesis of Alzheimer disease and vascular dementia. We investigated the serum concentration of nitric acid in 20 patients with probable Alzheimer disease, 20 patients with probable vascular dementia and in 19 control subjects. We also aimed to determine the association between this concentration and cognitive impairment tested by Mini-Mental State Examination in the disease groups.