Silvia Pellitero

Upregulation of lipocalin 2 in adipose tissues of severely obese women: positive relationship with proinflammatory cytokines.

Because the role of lipocalin 2 (LCN2) in morbid obesity is still not well defined, the aim of this study was to evaluate the circulating levels and the expression of LCN2 in visceral (VAT) and subcutaneous adipose tissue (SAT) in severely obese (SO) women. We also analyzed its relationship with inflammatory cytokines in the same subjects. The study comprised 90 white women, 39 of whom were lean controls (BMI ≤25 kg/m2) and 51 SO (BMI ≥40 kg/m2). Both circulating and adipose tissue levels of LCN2 were quantified by enzyme‐linked immunosorbent assays. LCN2 mRNA levels from VAT and SAT were assessed by real‐time reverse transcriptase‐PCR (n = 60). LCN2 serum levels were significantly higher in the SO women than in the lean controls (P = 0.042), and were found to be strongly correlated with tumor necrosis factor receptor I (TNFR1) circulating levels. In the SO cohort, LCN2 serum levels were also associated with higher BMI values, but not with the homeostasis model assessments of insulin resistance (HOMA2‐IR). LCN2 mRNA expression was markedly higher in SO women than in lean women in both VAT (P = 0.043) and SAT (P = 0.031). In SAT, LCN2 was negatively correlated with adiponectin and adiponectin receptor‐2 expression, and positively with interleukin‐6 (IL‐6) expression. A strong positive correlation was also found between LCN2 expression and the mean diameter of adipocytes in VAT. Our results revealed that the circulating level of LCN2 is associated with obesity and BMI. LCN2 mRNA is over‐expressed in adipose tissue from SO subjects. Finally, the expression of LCN2 is strongly related to an expression profile of proinflammatory cytokines but not to insulin resistance in nondiabetic SO women.

Plasma visfatin levels and gene expression in morbidly obese women with associated fatty liver disease.

OBJECTIVES The few studies on the physiopathological role of visfatin in morbid obesity and the related metabolic diseases have led us to examine visfatin levels and its liver gene expression in morbidly obese women with non-alcoholic fatty liver disease (NAFLD). DESIGN AND METHODS We examined the circulating levels of visfatin by ELISA in serum samples from 95 morbidly obese women (MO) (BMI>40 kg/m(2)) who underwent bariatric surgery and 38 normal weight control women (BMI<25 kg/m(2)). We analysed visfatin liver and adipose tissue mRNA expression by RT-PCR. We evaluated the circulating levels and gene expression of adiponectin, resistin, RBP4, TNFα, IL6 and CRP. RESULTS Serum visfatin was significantly higher in MO compared with controls, and also in MO with NAFLD was significantly higher than MO with normal liver. We found that NAFLD diabetic patients presented similar serum visfatin levels than non-diabetic. Serum visfatin correlated with IL6 (r=0.496; p<0.001) and CRP levels (r=0.241; p=0.049). Liver visfatin expression was significantly higher in MO compared to controls and was also significantly higher in MO with NAFLD than in MO with normal liver. Visfatin liver expression correlated positively with resistin (r=0.436, p=0.018) and TNFα expression (r=0.328, p=0.028). Visfatin expression in adipose tissues was similar among the MO groups analysed. CONCLUSION Serum visfatin and its liver expression are higher in MO women with NAFLD, irrespective of the presence of diabetes. Serum visfatin and its liver expression correlate positively with pro-inflammatory factors. These findings suggest that visfatin may be a molecule related with fat inflammation in morbid obesity and fatty liver disease.

Increased levels and adipose tissue expression of visfatin in morbidly obese women: the relationship with pro‐inflammatory cytokines

Objective  The controversial results on the physiopathological role of visfatin led us to examine both circulating visfatin levels and gene expression in visceral (VAT) and subcutaneous fat (SAT) in a homogeneous group of morbidly obese women.

Liver lipocalin 2 expression in severely obese women with non alcoholic fatty liver disease.

BACKGROUND Lipocalin 2 (LCN2) has been related to obesity, insulin resistance and metabolic disturbance. However, its relation with non alcoholic fatty liver disease (NAFLD) has hardly been studied. METHODS We examined LCN2 circulating levels and its protein and gene expression in liver from women with severe obesity and NAFLD. We analyzed the liver histology of 59 white severely obese women (BMI ≥40 Kg/m²): 15 subjects presented normal liver histology or non-significant liver disease (NL), 18 simple steatosis (SS) and 26 non alcoholic steatohepatitis (NASH). We determined the anthropometric and metabolic features of the women. LCN2 levels were determined by an ELISA and liver mRNA expression by real time RT-PCR. We also studied LCN2 expression in HepG2 liver cells under various inflammatory stimuli. RESULTS Liver LCN2 protein and gene expression were higher in NAFLD than in obese with NL. Liver LCN2 gene expression correlated with SS (r=0.351, p=0.016), and its protein expression correlated with NASH (r=0.705, p=0.003). LCN2 expression was detected in HepG2 cells after the administration of TNFα, IL6, resistin or adiponectin. LCN2 expression was induced by TNFα, IL6 and resistin. CONCLUSIONS Liver LCN2 is related to NAFLD in severely obese women. Up-regulation of LCN2 expression is detected in HepG2 cells after exposure to TNFα, IL6 and resistin. These results suggest that LCN2 expression is induced under liver harmful conditions.

Polymorphisms in platelet glycoproteins Ia and IIIa are associated with arterial thrombosis and carotid atherosclerosis in type 2 diabetes

To determine the genotype distributions of the polymorphisms in platelet glycoproteins (GP) Ib-alpha, Ia/IIa and IIb/IIIa and their association with clinical arterial thrombosis and preclinical carotid atherosclerosis in type 2 diabetes we studied 229 patients with type 2 diabetes and 229 controls matched by age, gender and ethnicity. Biochemical and haemostasis analyses were performed. The GP Ib-alpha VNTR, GP Ia 807 C/T and GP IIIa Pl(A) polymorphisms were determined by PCR. Thrombotic events were registered and carotid atherosclerosis was evaluated by ultrasound examination. A total of 107 patients had clinical atherothrombosis (CA), 65 subclinical atherosclerosis (SA), and 57 had no evidence of atherosclerosis (NA). There were no differences in allele frequencies and the genotype distribution of platelet GP polymorphisms between diabetic patients and controls. The VNTR Ib-alpha polymorphism was not associated with CA. We found a significant association between CA and the 807T (odds ratio [OR]: 2.86, confidence interval [CI]: 1.65-4.93; p<0.001) and PlA2 (OR: 2.03, CI: 1.13-3.65; p=0.03) alleles (in GP Ia and GP IIIa, respectively) in comparison to SA and NA group. Diabetic patients with the coexistence of the 807T and PlA2 alleles presented the highest risk of CA (OR: 3.59, CI: 1.64-7.8; p<0.001). The coexistence of both 807T and PlA2 alleles was also associated with the presence of SA (OR: 9.00, CI: 1.10-73.42; p=0.04). In conclusion, the 807T allele of GP Ia and the PlA2 allele of GP IIIa, and specially its combination, may confer an additional risk for development of carotid atherosclerosis and arterial thrombosis in type 2 diabetes.

Association of the IGF1/pregnancy-associated plasma protein-A system and adipocytokine levels with the presence and the morphology of carotid plaques in type 2 diabetes mellitus patients with stable glycaemic control

OBJECTIVE Pregnancy-associated plasma protein-A (PAPP-A) has been implicated in the atherosclerotic process through regulation of local expression of IGF1. In type 2 diabetes mellitus, glycaemic control has been involved in PAPP-A expression. We compared PAPP-A, IGF1, inflammatory markers and adiponectin concentrations in type 2 diabetic patients with and without carotid plaques and evaluated the relationship between these serum parameters and ultrasound carotid markers of atherosclerosis. METHODS We studied 125 consecutive type 2 diabetic patients. Clinical data, metabolic variables, hemostatic factors (plasma type-1 plasminogen activator inhibitor, fibrinogen), high-ultrasensitive C reactive protein (hsCRP), tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, adiponectin, IGF1 and PAPP-A were determined. Patients were classified into two groups according to the presence of carotid plaques on ultrasound. Carotid intima-media thickness (IMT) and morphology of carotid plaques were evaluated. RESULTS The mean age was 61.5+/-7.3 years and the mean glycated hemoglobin of 6.8+/-0.9%. A total of 60% presented carotid plaques. Both groups were homogeneous in anthropometric data, biochemical determinations and hemostatic factors. Adiponectin, hsCRP, TNF-alpha and IL-6 were similar in both groups. No differences were observed in serum PAPP-A (0.46 (0.22-0.86) vs 0.38 (0.18-0.66) mIU/l and in SDS IGF1 (-0.34+/-1.38 vs -0.67+/-1.35)) in patients with and without carotid plaques respectively. PAPP-A and IGF1 were not correlated with IMT. CONCLUSIONS Serum PAPP-A and IGF1 do not appear to be useful serum biomarkers for carotid atherosclerosis in type 2 diabetic patients with stable glycemic control, despite scientific evidence of their local role in atherosclerosis.

Low Prevalence of Subclinical Atherosclerosis in Asymptomatic Patients With Type 1 Diabetes in a European Mediterranean Population

OBJECTIVE To evaluate the presence of early carotid and coronary atherosclerosis in asymptomatic patients with type 1 diabetes with no history of ischemic heart disease. RESEARCH DESIGN AND METHODS One hundred and fifty patients with type 1 diabetes (58% males; 38.6 ± 8.1 years, 20.4 ± 8.1 years of evolution; HbA1c 8.1 ± 2.3%; 52% nonsmokers; 26% retinopathy; 9% microalbuminuria) and 50 nondiabetic control subjects age and sex matched were studied. Carotid ultrasonography to determine common carotid artery intima-media thickness (c-IMT) and the presence of atheroma plaques and cardiac computed tomography for calcium analysis and quantification (coronary artery calcium score [CACS]) were performed. RESULTS Most patients with type 1 diabetes and control subjects displayed a CACS of 0 (82 vs. 92%). Patients with type 1 diabetes with CACS ≥1 were older and had higher HbA1c (44.5 ± 5.1 vs. 36.7 ± 8.1 years [P < 0.001] and 8.5 ± 1.1 vs. 7.8 ± 1.0% [P < 0.003], respectively) and longer evolution of diabetes (25.4 ± 9.2 vs. 19.3 ± 7.4 years, P < 0.005) and mean c-IMT (0.67 ± 0.18 vs. 0.53 ± 0.11 mm, P < 0.001) compared with patients with CACS of 0. Smoking (P < 0.02), nephropathy (P < 0.05), retinopathy (P < 0.05), and male sex (P < 0.03) were significantly and positively associated with CACS ≥1. Mean c-IMT was significantly higher in patients with type 1 diabetes (0.55 ± 0.14 vs. 0.48 ± 0.14 mm, P < 0.01), and 11% of them presented atheroma plaques (8% of control subjects). Multivariant logistic regression analysis showed that c-IMT was related to CACS (β = 6.87, P < 0.001). CONCLUSIONS A small percentage of patients with type 1 diabetes showed data suggestive of subclinical atherosclerosis. Universal screening of coronary disease in this population is not justified. Carotid ultrasonography may be useful for screening in the subset of patients with cardiovascular risk factors and long disease evolution.

Leptin and Thyrotropin Relationship Is Modulated by Smoking Status in Euthyroid Subjects

BACKGROUND The relationship between thyrotropin (TSH) concentrations and body mass index (BMI) in euthyroid subjects has been demonstrated only in some studies. Leptin regulates TSH secretion and TSH stimulates leptin secretion. The main aims of our study were to assess the relationship between leptin, the thyroid axis, and thyroid autoimmunity in a representative sample of a nonhospitalized euthyroid adult population of Catalonia and to determine whether smoking status could influence this relationship. METHODS This cross-sectional population-based study includes 894 euthyroid iodine-sufficient adults (390 men, 44.87±15.03 years old) with BMI 26.19±4.61 kg/m(2), representative of people living in Catalonia. The study analyzes the relationship between TSH, free thyroxine (FT4), leptin, thyroperoxidase and/or thyroglobulin antibodies (thyroid autoimmunity), smoking status, and BMI. Measurements also include glycemia and insulinemia to calculate homeostasis model assessment of insulin resistance (HOMA-IR) index as a measure of insulin sensitivity. RESULTS In the univariate analysis and in the overall group, TSH correlated directly with BMI, leptin, and HOMA-IR (p=0.039, p<0.001, and p=0.010, respectively). In all men, TSH correlated directly with leptin (p=0.004), and in all women, directly with leptin (p=0.002) and HOMA-IR (p=0.031) and inversely with FT4 (p=0.024). Only in men who smoke, TSH correlated directly with leptin (p=0.010) and HOMA-IR (p=0.024). In women, TSH correlated directly with leptin (p=0.004) and in nonsmoking women, inversely with FT4 (p=0.047). In the multiple regression analysis, age (β=-0.00310, p=0.0265), smoking status (β=-0.24085, p=0.0202), and thyroid autoimmunity (β=0.20652, p=0.0075) were independent predictors of TSH variations. Leptin was a significant independent predictor of TSH variations only in smokers (β=0.16451, p=0.047). CONCLUSIONS Leptin is an independent predictor of TSH concentration variations only in euthyroid smoker subjects of both sexes at all ranges of BMI, but not in nonsmokers. Age, smoking status, and positive thyroid autoimmunity also influenced TSH variability.

IGF1 modifications after bariatric surgery in morbidly obese patients: potential implications of nutritional status according to specific surgical technique.

OBJECTIVES IGF1 is decreased in morbidly obese (MO) patients and its changes after bariatric surgery weight loss (WL) are not well known. The aim of this study was to analyse IGF1 modifications in MO patients after WL and its relationship to ghrelin and to different types of surgeries. DESIGN Retrospective follow-up study at the University Medical Center. METHODS One hundred and nine MO patients (age 44.19.3, BMI 51.748.75KG/M(2)) were evaluated at baseline and 1 year after surgery: 28 sleeve gastrectomy (SG), 31 distal modified (m), and 50 ringed (r) Roux-en-Y gastric bypass (RYGBP) surgery. Changes in IGF1, IGFBP3, ratio IGF1:IGFBP3, and ghrelin were evaluated 1 year after surgery. RESULTS Baseline prevalence of low IGF1 (defined by s.d. IGF1<-2) was 22%, and %WL 1 year after surgery was 34.9±8.9%. There was a significant decrease in IGFBP3 in all the procedures, an increase in IGF1:IGFBP3 ratio in rRYGBP and SG, but total IGF1 only increased significantly in SG. Albumin concentrations decreased in mRYGBP, did not change in rRYGBP, but increased in SG after surgery. Total ghrelin concentrations increased after both RYGBPs and decreased after SG (P<0.05 in all cases). The prevalence of low IGF1 decreased in SG (28.6 vs 10.1%, P=0.03) and did not change in RYGPBP techniques. The %albumin change was the only dependent variable associated with the % total IGF1 change. CONCLUSIONS Recovery of low IGF1 after bariatric surgery was specifically related to the albumin modifications induced by surgery and was not related to ghrelin modifications.

Non-detectable Chlamydophila pneumoniae DNA in peripheral leukocytes in type 2 diabetes mellitus patients with and without carotid atherosclerosis

BACKGROUND AND OBJECTIVE To study Chlamydophila pneumoniae DNA (CP-DNA) in leukocytes measured by real-time polymerase chain reaction (PCR) in patients with type 2 diabetes mellitus (DM2) with different degrees of atherosclerosis, a cross-sectional protocol was performed. PATIENTS AND METHODS We included 135 patients with DM2. Clinical, metabolic and inflammatory variables were measured. Previous clinical macrovascular disease was recorded and carotid ultrasound and real-time PCR for CP-DNA were performed. RESULTS Mean age was 62 (7) years and mean diabetes duration 16 (9) years; 40.7% of patients presented clinical atherosclerosis, 32.5% subclinical atherosclerosis and 26.6% no evidence of atherosclerosis. Anthropometric data were homogeneous in the three groups. Patients with clinical atherosclerosis had greater carotid intima-media thickness compared to the other two groups. No CP-DNA was detected in any patient. CONCLUSIONS The lack of detection of CP-DNA in blood leukocytes suggests that C. pneumoniae plays no active, systemic role in the pathogenesis of atherosclerosis in DM2 patients and is not a reliable marker of atherosclerosis in high-risk patients.