Relationship of proprotein convertase subtilisin-kexin type 9 levels with resistin in lean and obese subjects

ObjectivesProprotein convertase subtilisin-kexin type 9 (PCSK9), a key regulator of low density lipoprotein receptor expression, has recently been reported to be upregulated by resistin in HepG2 cells and human primary hepatocytes. Whether this translates into a positive relationship of plasma PCSK9 with resistin levels in humans with varying degrees of obesity is unknown.Design and methodsWe assessed the extent to which plasma PCSK9 levels are determined by resistin in individuals with varying degrees of obesity.ResultsIn 80 subjects (35 women; no diabetes mellitus) with body mass index ranging from 19.4 to 40.4 kg/m², plasma PCSK9 levels were not positively related to resistin (r = ? 0.161, p = 0.154). Despite positive correlations of non-high density lipoprotein cholesterol (r = 0.378, p < 0.001), low density lipoprotein (r = 0.292, p < 0.01) and apolipoprotein B (apoB) (r = 0.266, p < 0.05) with PCSK9, none of these apolipoprotein (apo) B-containing lipoprotein measures was positively related to resistin (p > 0.10 for all). In subjects with BMI < 25.0 kg/m² (n = 38), PCSK9 was even inversely related to resistin (r = ? 0.322, p = 0.049), and this relationship remained present after controlling for either leptin (p = 0.027) or insulin resistance (P = 0.031). In subjects with BMI ≥ 25.0 kg/m² (n = 42), PCSK9 was unrelated to resistin (r = ? 0.064, p = 0.69).ConclusionsThis study demonstrates that there is no positive association of plasma PCSK9 with resistin in lean and moderately obese individuals. Our data question whether circulating resistin is a physiologically important determinant of higher PCSK9 levels.     

Plasma high sensitivity C-reactive protein and its relationship with cytokine levels in children with newly diagnosed type 1 diabetes and ketoacidosis

BackgroundHigh-sensitivity C-reactive protein (hs-CRP) and pro-inflammatory cytokines have been suggested as sensitive markers of endothelial dysfunction. Our aim was to monitor plasma hs-CRP levels at different time-points and in different degrees of ketoacidosis severity, its association with cytokine levels and its role as a marker of severe ketoacidosis complications.Patients and methodsWe studied in 38 newly diagnosed children with type 1 diabetes and ketoacidosis, aged 7.7 ± 3.1 years, hs-CRP, white blood cell count (WBC), and plasma levels of cytokines IL-1β (interleukin-1β), IL-2, IL-6, IL-8, IL-10, TNF-α (tumor necrosis factor-α) prior to and during DKA management.ResultsOn admission, the levels of WBC, PMN, IL-6 and IL-10 were elevated, but were all reduced within 120 h after ketoacidosis management. In the group with moderate/severe ketoacidosis, but not in mild ketoacidosis, hs-CRP levels were significantly reduced at 24 h (p = 0.021), WBC and IL-6 at 120 h (p = 0.003), while IL-10 was prematurely reduced at 6–8 h (p = 0.008). Moreover hs-CRP was significantly associated with WBC (p = 0.023) and IL-6 (p = 0.028) on admission, with IL-6 (p = 0.002) and IL-8 (p = 0.014) at 24 h and with IL-10 (p = 0.027) at 120 h. The above were not observed in the group with mild ketoacidosis.ConclusionsIn the children with moderate/severe diabetic ketoacidosis of our study, increased levels of hs-CRP and IL-6 were observed, together with leukocytosis and neutrophilia, without the presence of infection. As hs-CRP was found to be strongly associated with the inflammatory IL-6, the prolonged elevation of hs-CRP levels in children with severe ketoacidosis could serve as a marker for the development of its severe complications.     

Concentrations of omentin and vaspin versus insulin resistance in obese individuals

IntroductionOmentin and vaspin are adipokines manifesting a potentially protective action against obesity-associated metabolic disturbances.AimEvaluation of relationship between serum concentrations of omentin and vaspin on one hand and indices of insulin resistance and anthropometric parameters in obese individuals on the other.Material and methodsThe studies were conducted on 64 individuals. The investigated group (37 obese patients) included the subgroup with normal glucose tolerance (NGT) and with abnormal glucose tolerance (AGT). The control group (n = 27) included healthy individuals with normal body weight. In all participants anthropometric analyses and biochemical tests, including estimation of omentin and vaspin concentrations were performed, and insulin resistance by HOMA-IR was evaluated.ResultsConcentrations of examined adipokines manifested no significant differences between the examined groups. Median values of the index defining ratio between studied adipokine and degree of insulin resistance, i.e. omentin/HOMA-IR, proved to be different in the investigated and the control group while no such difference could be noted in cases of vaspin/HOMA-IR indices. In the studied population a negative relationship was detected between serum concentration of omentin and systolic blood pressure (p < 0.04). Values of omentin/HOMA-IR index manifested a correlation with values of most anthropometric parameters (p < 0.0001), blood pressure (p < 0.0001) concentrations of TG (p < 000.1) and HDL (p < 0.0001), ISI_basal (p < 0.00001), ISI_gly (p < 0.0001), Quicki (p < 0.00001) and fasting insulinaemia (p < 0.00001). In the case of vaspin/HOMA-IR index only its positive relationship with HDL concentration was noted (p < 0.05).ConclusionIn context of date of correlation, multiple regression and values of area of under receiver operating characteristics curve omentin, as compared to vaspin, seems to provide a better predictor of insulin resistance in obese individuals.     

Assessment of matrix metalloproteinase (MMP)-2, MMP-8, MMP-9, and their inhibitors,the tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 in obese children and adolescents

ObjectivesTo compare the circulating levels of matrix metalloproteinase (MMP)-8, pro-MMP-2, pro-MMP-9, and total MMP-9, their endogenous inhibitors, the tissue inhibitors of metalloproteinases (TIMP)-1 and TIMP-2, and the MMP-8/TIMP-1, MMP-9/TIMP-1, and MMP-2/TIMP-2 ratios in normotensive obese children and adolescents with those found in non obese children and adolescents.Design and methodsWe studied 40 obese and 40 non obese (controls) children and adolescents in this cross-sectional study. MMP and TIMP concentrations were measured in plasma samples by gelatin zymography and ELISA.ResultsObese children and adolescents had higher circulating MMP-8 concentrations, lower plasma TIMP-1 concentrations, and higher MMP-8/TIMP-1 ratios than non obese controls (P < 0.05). We found no differences in pro-MMP-9 or total MMP-9 levels, or in MMP-9/TIMP-1 ratios between groups (P > 0.05). While we found no significant differences in pro-MMP-2 levels (P > 0.05) obese subjects had higher TIMP-2 concentrations and lower pro-MMP-2/TIMP-2 ratios (P < 0.05) than non obese controls.ConclusionsIn conclusion, we found evidence indicating higher net MMP-8 (but not MMP-9 and MMP-2) activity in childhood obesity. The increased MMP-8 levels found in obese children suggest a possibly relevant pathophysiological mechanism that may be involved in the increase of cardiovascular risk associated with childhood obesity.     

Evaluating the impact of obesity on safety and efficacy of weight-based norepinephrine dosing in septic shock: A single-center,retrospective study

ObjectiveNorepinephrine is the first-line vasopressor recommended for patients in septic shock. Weight-based dosing may increase drug exposure and the risk of adverse effects in obese patients. The objective was to evaluate the safety and efficacy of weight-based norepinephrine dosing using actual body weight in the morbidly obese compared with normal weight patients.MethodsThis was a single centre, retrospective study of adult patients admitted with septic shock requiring norepinephrine for at least 12 hours. The primary endpoint was the incidence of tachycardia within 48 hours after norepinephrine initiation. Secondary endpoints included timing and dosing of norepinephrine when adjunctive agents were added.ResultsThe incidence of tachycardia was similar between groups. Total norepinephrine exposure was significantly greater in obese patients on day 1 (p = 0.02). Obese patients were more likely to be started on vasopressin (p < 0.001) and steroids at a lower weight-based norepinephrine dose (p = 0.016).ConclusionsWeight-based norepinephrine dosing using actual body weight did not result in more tachycardia in the morbidly obese compared to normal weight patients, despite greater total exposure. These results were limited by the low doses used and a small cohort. However, use of actual body weight in morbidly obese patients appears to be safe.     

Time of sampling is crucial for measurement of cell-free plasma DNA following acute aseptic inflammation induced by exercise

ObjectivesTo determine the time-course changes of cell-free plasma DNA (cfDNA) following heavy exercise.MethodscfDNA concentration, C-reactive protein levels (hs-CRP), uric acid concentration (UA), creatine kinase activity (CK) were measured before and post-exercise (immediately post, 0.5 h, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 8 h, 10 h, 24 h).ResultscfDNA increased (15-fold) 30-min post-exercise and normalized thereafter. hs-CRP increased (56%, p < 0.001) 1 h post-exercise, remained elevated throughout recovery (52–142%, p < 0.0001), and peaked (200% rise, p < 0.0001) at 24 h post-exercise. UA and CK increased (p < 0.05), immediately post-exercise, remained elevated throughout recovery (p < 0.0001), and peaked (p < 0.0001) at 24 h of post-exercise recovery.ConclusionscfDNA sampling timing is crucial and a potential source of error following aseptic inflammation.     

The prognostic value of serum pregnancy-associated plasma protein A,S100 and high sensitivity C-reactive protein in acute ischemic stroke patients without heparin administration

ObjectivesThe concerns regarding the pre-analytical bias caused by medicine treatments have been raised in the diagnosis and prognosis of ischemic stroke recently. The aim of this study was to examine the prognostic value of serum pregnancy-associated plasma protein A (PAPP-A), S100 and high sensitivity C-reactive protein (hs-CRP) in heparin-naïve patients of acute ischemic stroke.Design and methodsSerum levels of PAPP-A, S100 and hs-CRP were determined in 205 heparin-naïve patients of acute ischemic stroke and 50 healthy controls. Clinical information and radiological information were collected. Unfavorable outcomes (stroke recurrence, myocardial infarction or death) were also recorded after six months. The associations between serum biomarker levels and stroke severity/outcome were assessed.ResultsSerum PAPP-A, S100 and hs-CRP levels increased in patients compared with controls (P < 0.05). S100 and hs-CRP levels were significantly higher in patients with larger cerebral infarction sizes (P < 0.05) and more severe neurological impairment (P < 0.05). Serum PAPP-A level showed a progressive increase with the increase of stroke severity (P < 0.05). Serum hs-CRP and National Institutes of Health Stroke Scale (NIHSS) scores were identified as independent predictors for unfavorable outcomes with odds ratios of 2.884 (1.154 to 7.210, P = 0.023) and 2.887 (1.146 to 7.273, P = 0.024), respectively.ConclusionSerum PAPP-A, S100 and hs-CRP were associated with stroke severity or outcome after ischemic stroke and may offer complementary information, essential for clinical decision making. Serum PAPP-A showed a potential value for the evaluation of stroke clinically.     

Twenty-four-hour profiles of urinary excretion of calcium,magnesium, phosphorus,urea, and creatinine in healthy prepubertal boys

ObjectivesAvailable data on 24-h urinary solute excretion in healthy children are sparse. We thus documented the daily and overnight variations of urinary electrolytes (calcium, magnesium, and phosphorus), urea, and creatinine in prepubertal (Tanner stage I) boys.Design and methodsNine voluntary healthy prepubertal boys aged 10.8 ± 0.11 years participated in this study. Concentrations of variables were quantified in daytime samples (collected between 07:00 h ± 30 min and 21:00 h ± 30 min) and nighttime samples (collected between 21:00 h ± 30 min and 07:00 h ± 30 min) in spring, during a period of 24-h every 3 h.ResultsSignificant differences were found between daytime and nighttime excretion of calcium (p < 0.05), magnesium (p < 0.001), phosphorus (p < 0.01), and urea (p < 0.05), with high concentrations during the night. The 24-h solute/creatinine ratio was 0.072 ± 0.008 mg/mg for calcium, 0.069 ± 0.008 mg/mg for magnesium, 0.698 ± 0.070 mg/mg for phosphorus, and 0.017 ± 0.001 g/mg for urea. Statistically significant correlation analyses showed that urea and creatinine were positively associated with body mass index (BMI) (R = 0.790, p = 0.0113 for urea; R = 0.889, p = <0.0013 for creatinine) and weight (R = 0.717, p = 0.0297 for urea; R = 0.978, p = < 0.001 for creatinine). The other urinary variables were independent of BMI and body mass.ConclusionThese data are of interest for the diagnosis of certain renal disease in prepubertal children.     

Relationship between obesity and metabolic syndrome among Argentinean elementary school children

BackgroundArgentina has experienced marked increases in the prevalence of childhood overweight (OW)/obesity over the last few decades.ObjectivesWe examined (1) the distribution of the mean values of lipids, glucose, and HOMA-IR according to the presence of OW/obesity, age, and sex and (2) the association between metabolic syndrome and OW/obesity, Tanner stage, gender, and HOMA-IR.MethodsData were collected from 1009 children (508 males) in 10 elementary schools between April and September 2007. BMI, waist circumference, blood pressure, Tanner, lipids, insulin, and glucose were determined. Criteria analogous to ATPIII were used for metabolic syndrome in children.ResultsOver 1009 children (508 males) aged 9.4 ± 2.0 years were evaluated. One hundred and sixty-five (16.4%) were obese (> 95th percentile), and 166 (16.5%) were OW (85-95th). Twenty-five (2.5%) were severely obese (BMI > 99th). Most of the children (62%; 613/979) were at Tanner 1. Triglycerides, insulin, and HOMA-IR were higher (p < 0.001) and HDL-C lower (p < 0.001) in OW/obesity in both age groups and genders. The prevalence of metabolic syndrome was 5.8% overall, 32% in severely obese, 16.4% in OW/obese and 0.4% in normal weight children. Multiple logistic regression showed that BMI (OR 24.48; 95% CI 9.14–65.57), and HOMA-IR (OR 2.09; 95% CI 1.04–4.18) were associated with metabolic syndrome adjusted by gender and Tanner stage. Multiple linear regression also showed that BMI and HOMA-IR were independently associated with the number of metabolic syndrome components (R² = 0.46).ConclusionsA substantial number of OW/obese children have the metabolic syndrome. HOMA-IR and BMI were strong predictors of metabolic syndrome in children suggesting that OW/obese school children are at a higher risk for future cardiovascular disease.     

Reduced serum vaspin concentrations in obese children following short-term intensive lifestyle modification

BackgroundRecently, visceral adipose tissue-derived serpin (vaspin) was identified as a potential insulin sensitizing adipokine, however, the factors determining the levels of circulating vaspin levels have not been fully understood. We investigated the association between adiposity, insulin resistance, lipid profiles and inflammatory markers including vaspin levels, and the effects of short-term intensive lifestyle modification on circulating vaspin levels in overweight or obese children.MethodsA total of 50 (25 boys, 25 girls) overweight or obese children aged 11 to 13 years (average age: 12.0 ± 0.9 y, BMI: 25.35 ± 86 kg/m²) who complied with inclusion criteria participated in our study. To determine the association between adiposity, insulin resistance, lipid profiles and inflammatory markers including vaspin levels, cross-sectional analyses were performed. Thereafter, subjects underwent a tightly controlled seven-day intensive lifestyle modification including physical activity, dietary modification, and behavioral modification education in residence of a local university dormitory.ResultsThere was a negative correlation between vaspin concentration and fasting insulin (r = ?.325, p < 0.05) and homeostasis model assessment of insulin resistance (HOMA-IR) (r = ?.331, p < 0.05) when percent body fat was controlled. Multivariate linear regression analysis found serum vaspin level to be an independent predictor of insulin and HOMA-IR. Short-term intensive lifestyle modification significantly decreased vaspin levels by 39.28% (pre: .84 ± 1.0, post: .51 ± 1.0 ng/ml, p < 0.001) while adiponectin levels increased by 11.2% (pre: 6.50 ± 2.89, post: 7.28 ± 2.98 ng/ml, p < 0.01). In addition, short-term lifestyle modification significantly improved HOMA-IR (pre: 3.58 ± 1.93, post 1.30 ± 1.9, p < 0.001) and lipid profiles.ConclusionsSerum vaspin level is one of the predictors for insulin resistance and was significantly reduced following short-term lifestyle modification.     

Diagnostic performance of BNP and NT-ProBNP measurements in children with heart failure based on congenital heart defects and cardiomyopathies

ObjectivesTo test the diagnostic performance of BNP and NT-ProBNP in children with different hemodynamic dysfunctions.Design and methodsSeventy children who underwent echocardiography and were classified into left and right ventricle volume and pressure overload (LVvO, LVpO, RVvO, and RVpO, respectively) and biventricular volume overload (BVvO) were enrolled.ResultsBNP and NT-ProBNP levels in all groups were higher than those in the control group (p < 0.001, p < 0.001). The increase in peptide levels was strongly correlated with the severity of heart failure (p < 0.001, p < 0.001). There was no significant difference in peptide levels in-between LVvO, LVpO, RVvO, RVpO and BVvO groups. Both measurements were significantly correlated (r = 0.76, p < 0.001) with each other. NT-ProBNP showed a high sensitivity, whereas BNP showed a high specificity and accuracy. AUCs in ROC-curve were 0.97 for BNP and 0.96 for NT-ProBNP.ConclusionsNT-ProBNP may be used in screening of risk groups for cardiac failure because of its' higher sensitivity, but BNP may be specifically used in monitoring patients with heart failure.     

Yoga’s effect on falls in rural,older adults

BackgroundUnintentional falls affect 30% of people over age 65 years. Yoga has been shown to improve balance. We designed this study to examine if yoga reduces falls.MethodsWe conducted 16 sessions of Hatha yoga over 8 weeks. Participants were randomly assigned to practice 10 min of yoga daily at home in addition to 5-min relaxation exercises or relaxation exercises only (control group).ResultsOf the 38 participants completing the intervention, 15 participants reported a total of 27 falls in the 6-months before the study, compared to 13 participants sustaining 14 falls in the 6 months from the start of the study (p < 0.047), without difference between yoga home-exercise and home relaxation-only groups.Compared to baseline scores, all participants improved on the Berg Balance Scale (53–54 out of 56, p = 0.002), the Functional Gait Assessment (22.9–25.8 out of 30 points, p < 0.001), and the Dynamic Gait Index (20.6–22.4 out of 24 points, p < 0.001). Right leg stand time improved from a mean of 13.3 s to 17.1 s (p = 0.020) and standing forward reach distance from 26.0 cm to 29.6 cm (p < 0.001). Without difference between groups.Confidence, with the Activities-specific Balance Confidence Scale, increased in the yoga home-exercise group (88%–93%, p = 0.037) compared to 90% unchanged from pre-intervention in the home relaxation-only group.ConclusionYoga classes reduce self-reported falls and improve balance measures. The addition of home yoga exercises did not enhance benefit over relaxation exercise only.     

Serum levels of pigment epithelium-derived factor,a novel marker of insulin resistance,are independently associated with fasting apolipoprotein B48 levels in humans

ObjectivesFasting apolipoprotein B48 (apoB48) levels are associated with postprandial hyperlipidemia and carotid artery intima-media thickness (IMT), one of the markers of metabolic derangements and atherosclerosis, respectively. However, it remains unknown whether fasting serum levels of apoB48 are independently correlated with insulin resistance and vascular inflammation in humans.Design and methodsThe study involved 315 consecutive outpatients in our hospital (218 males and 97 females) with a mean age of 62.0 ± 9.2. We examined which anthropometric, metabolic and inflammatory variables, including serum levels of pigment epithelium-derived factor (PEDF), a novel marker of insulin resistance were independently associated with fasting apoB48. Moreover, we investigated whether fasting apoB48 levels were correlated with atherosclerotic plaque inflammation evaluated by [¹⁸F]-fluorodeoxyglucose positron emission tomography (FDG-PET). Carotid [¹⁸F]-FDG uptake, an index of vascular inflammation within the atherosclerotic plaques, was measured as blood-normalized standardized uptake value, known as the target-to-background ratio (TBR).ResultsMean serum levels of apoB48, PEDF, carotid IMT and TBR values were 2.77 ± 0.21 μg/mL, 13.45 ± 1.03 μg/mL, 0.71 ± 0.15 mm, and 1.43 ± 0.21, respectively. Univariate analysis revealed that apoB48 levels were weakly, but not significantly associated with TBR (p = 0.057). In multiple stepwise regression analysis, triglycerides (p < 0.001), male (p = 0.039), age (inversely, p = 0.010), uric acid (p = 0.007), medication for diabetes (p = 0.029), and PEDF (p = 0.049) were independently correlated to fasting apoB48 levels (R² = 0.371).ConclusionsThe present study reveals that serum levels of PEDF are independently associated with fasting apoB48 levels, suggesting that PEDF level is a novel biomarker that could reflect postprandial hyperlipidemia in humans.     

Serum glycated albumin levels,but not glycated hemoglobin,is low in relation to glycemia in non-diabetic men with nonalcoholic fatty liver disease with high alanine aminotransferase levels

ObjectivesWe have reported that serum glycated albumin (GA) levels are low in obese subjects, smokers and hyperuricemic subjects in whom high sensitive CRP (hs-CRP) is elevated. Because patients with nonalcoholic fatty liver disease with high alanine aminotransferase (ALT) levels are reported to show high levels of hs-CRP, the relationship between serum ALT and serum GA levels was investigated.Design and methodsThis study comprised 196 non-diabetic men without drinking habit.ResultsCompared with the normal ALT group (serum ALT ≤ 30 U/L; n = 158), the high ALT group (serum ALT > 30 U/L; n = 38) had significantly higher fasting plasma glucose (PG), OGTT 2-h PG and HbA_1C levels. Meanwhile, serum GA was significantly lower, and hs-CRP was significantly higher in the high ALT group.ConclusionsThe results obtained indicate that serum GA is under a negative control of hs-CRP in subjects with high ALT without drinking habit.     

Soluble transferrin receptor in urine,a new biomarker for IgA nephropathy and Henoch–Schönlein purpura nephritis

ObjectivesIgA nephropathy (IgAN) and Henoch–Schönlein purpura nephritis (HSPN) might represent different ends of a continuous spectrum of glomerular disease. In both conditions, upregulated soluble transferrin receptor (sTfR) might be excreted in urine, which could be a potential biomarker to monitor disease activity and therapeutic response.MethodsIn this pilot study, 132 Caucasian patients consulting the Nephrology Department at the Ghent University Hospital because of a glomerulopathy and 50 normal controls were included. Urinary sTfR concentrations were determined in concentrated urine using a newly developed latex-enhanced immunonephelometric assay.ResultsMedian urinary sTfR concentration was higher in patients with a primary glomerulopathy than in healthy subjects (p < 0.0001). More importantly, absolute median levels of urinary sTfR were markedly higher in patients with active IgAN or HSPN [10 μg/L, 95% confidence interval (CI): 6–18 μg/L] in comparison with those with other morphological types of glomerulopathy (2 μg/L, 95%CI: 1–4 μg/L) (p < 0.0001). A statistically significant difference in urinary sTfR concentration was observed between patients with active IgAN or HSPN and patients who had achieved partial or complete remission (p < 0.0001). Multiple regression analysis with urinary sTfR as dependent variable revealed that proteinuria was the main predictor of urinary sTfR concentration (r² = 0.52, p < 0.001).ConclusionDetermination of sTfR in urine is a new and sensitive method for a potential biomarker of IgAN and HSPN.     

Evaluation of five immunoturbidimetric assays for urinary albumin quantification and their impact on albuminuria categorization

ObjectivesThe study was designed to evaluate the performance of five automated immunoturbidimetric assays to quantify urinary albumin, each corresponding to a combination of a reagent and an analyzer (Olympus on AU640®, Roche on Cobas Integra, Abbott on Architect, Ortho-Clinical Diagnostics Vitros on Fusion and Siemens on Dimension).Design and methodsTo assess imprecision, albumin was measured in three urinary pools with a mean value of 25, 66 and 131 mg/L. One hundred and eight patient urine samples were then used to compare each turbidimetric method using the Passing–Bablok regression and Bland–Altman analyses. Concordance of the albumin/creatinine ratio (ACR), according to the albuminuria classifications proposed by the KDIGO, was calculated to test the agreement between the different assays.ResultsAll immunoturbidimetric methods evaluated in this study exhibited acceptable imprecision (CV < 6%). Mean values for 108 urine samples varied from 0.5 to 762.2 mg/L. Significant differences were found (p < 0.05) between all methods except between Olympus and Ortho (p = 1.0) and between Abbott and Roche (p = 0.12). Regarding the albuminuria categories based on the ACR proposed by the KDIGO, only the classification obtained with the Roche method was significantly different from the four other methods (p < 0.001).ConclusionsWe demonstrated that all assays were not strictly equivalent which could affect ACR categories in clinical practice, suggesting the need for harmonization of commercial methods.     

Association of G-2548A LEP polymorphism with plasma leptin levels in Tunisian obese patients

ObjectivesThe aim of this study was to examine the association of the G-2548A polymorphism of the human leptin gene (LEP) with body mass index (BMI), plasma leptin, insulin, and lipid parameters in a sample of Tunisian population.Design and methodsTwo hundred and twenty nine obese patients (BMI ≥ 30 kg/m²) were screened and compared to 251 normal weight subjects (BMI < 25 kg/m²). The human leptin gene promoter G-2548A genotype was determined by polymerase chain reaction followed by a digestion with the restriction of endonuclease CfoI.ResultsIn the entire study sample, carriers of -2548A allele had significantly lower leptin levels than homozygous for -2548G allele (14.28 ± 9.10 ng/mL vs. 18.27 ± 12 ng/mL, p < 0.001 respectively) adjusted for BMI and gender. In obese patients but not control, subjects carrying the -2548A allele exhibited lower leptin levels than those with GG genotype (16.96 ± 8.27 ng/mL vs. 21.37 ± 11.72 ng/mL, p = 0.001 respectively) adjusted for BMI and gender. In this group, carriership of the -2548A allele was identified, by multiple linear regression models, as significant independent predictor for leptin levels variability. Separate analyses by gender revealed that only in obese women, the -2548A allele was found to be associated with lower leptin levels independently of BMI (p = 0.004).ConclusionsThe present study showed that G-2548A LEP polymorphism is associated with lower leptin levels in Tunisian obese women.     

Association between irisin and homocysteine in euglycemic and diabetic subjects

ObjectivesThe aim of study was to explore whether a relationship exists between homocysteine and irisin in type 2 diabetes (T2D) patients—a population with a high risk of developing cardiovascular disease—and euglycemic controls.Design and methods69 T2D patients and 75 control subjects (adjusted by body mass index (BMI)) were included in the study. Irisin and homocysteine concentrations and anthropometric and biochemical variables were determined.ResultsLevels of homocysteine were significantly higher (11.0 ± 3.0 vs 12.4 ± 4.2 μmol/l) and levels of irisin were lower (279 ± 58 vs 263 ± 38 ng/ml) in T2D patients. When both T2D and controls were considered, irisin was found to correlate only with homocysteine (r = − 0.215; p = 0.011). Moreover, a decreasing trend in irisin levels was observed according to homocysteine tertile (p = 0.034).ConclusionsOur results provide evidence of an association between irisin and homocysteine, which may be due to nicotinamide metabolism. The clinical significance of this relationship is unclear, but our findings may prompt further mechanistic research to investigate the role played by irisin in vascular disorders.