Adiponectin Expression and Adipose Tissue Lipolytic Activity in Lean and Obese Women

Background: The authors evaluated whether adipose adiponectin expression is related to adipose tissue lipolytic activity and fatty acid oxidation rate in lean and obese women. Methods:The study consisted of 60 adult females distributed in a wide range of adiposity (BMI 24.0-53.4 kg/m² ). Body composition was estimated by bioelectrical impedance. Respiratory quotient was measured by open-circuit indirect calorimetry. RT-PCR assays were performed to measure TNFα and adiponectin expression in subcutaneous adipose tissue biopsies. Lipolysis studies were performed in fresh tissue samples obtained from subcutaneous abdominal depots during bariatric surgery in 19 morbidly obese females or by an incisional biopsy or during abdominal elective surgery in normal weight and obese females. Glycerol release was measured with a colorimetric endpoint method. Results: Patients with a higher degree of adiposity showed lower adipose tissue adiponectin expression and hormone-sensitive lipase (HSL) activity than women in the low range of adiposity. HSL activity was positively related to adiponectin expression. No relationship was observed between adiponectin and TNFα subcutaneous adipose tissue expression. The positive relationship between respiratory quotient and adiponectin expression was in the limit of statistical significance (P=0.05). Percentage of body fat and mRNA adiponectin explained 26% of the variance of the adipose tissue HSL activity. Conclusions: Low adipose tissue adiponectin expression observed in obese people may contribute to the progression of obesity and its co-morbidities by modulating hormone-sensitive lipase activity and fatty acid oxidation.     

Higher Content of <Emphasis Type="Italic">Trans</Emphasis> Fatty Acids in Abdominal Visceral Fat of Morbidly Obese Individuals undergoing Bariatric Surgery compared to Non-Obese Subjects

Background: The purpose of this study was to determine the total content of trans fatty acids (TFA) in subcutaneous, retroperitoneal and visceral fat of morbidly obese and non-obese patients submitted to bariatric surgery or plastic and abdominal surgery. Methods: The adipose tissues were obtained by surgery; lipids were extracted, saponified and esterified. TFA were measured by FTIR-ATR spectroscopy. Results: The TFA average in obese patients was 6.3% for retroperitoneal and 8.7% for visceral fat. For non-obese patients, the figures were 6.9% (subcutaneous) and 9.3% (visceral). There was no difference between the groups. However, the TFA depot in visceral fat was higher than other fatty tissues for morbidly obese (P<0.001) and non-obese (P<0.05) patients. Conclusions: Our values for TFA content in all adipose tissues analyzed are higher than reported in other countries (3-6%). We showed more TFA in visceral adipose tissue than in other abdominal fat (subcutaneous and retroperitoneal) stores. The visceral adipose tissue level is worrisome because the higher rate of lipolysis in this tissue appears to be an important indicator of metabolic alterations and the levels of TFA found in adipose tissue presumably reflect the higher dietary intake of TFA by Brazilians.     

Gene Expression of Leptin, Resistin, and Adiponectin in the White Adipose Tissue of Obese Patients with Non-Alcoholic Fatty Liver Disease and Insulin Resistance

Background: Adipose tissue is an active endocrine organ that secretes a variety of metabolically important substances including adipokines. These factors affect insulin sensitivity and may represent a link between obesity, insulin resistance, type 2 diabetes (DM), and nonalcoholic fatty liver disease (NAFLD). This study uses real-time polymerase chain reaction (PCR) quantification of mRNAs encoding adiponectin, leptin, and resistin on snap-frozen samples of intra-abdominal adipose tissue of morbidly obese patients undergoing bariatric surgery. Methods: Morbidly obese patients undergoing bariatric surgery were studied. Patients were classified into two groups: Group A (with insulin resistance) (N=11; glucose 149.84 ± 40.56 mg/dL; serum insulin 8.28 ± 3.52 μU/mL), and Group B (without insulin resistance) (N=10; glucose 102.2 ± 8.43 mg/dL; serum insulin 3.431 ± 1.162 μU/mL). Results: Adiponectin mRNA in intra-abdominal adipose tissue and serum adiponectin levels were significantly lower in Group A compared to Group B patients (P<0.016 and P<0.03, respectively). Although serum resistin was higher in Group A than in Group B patients (P<0.005), resistin gene expression was not different between the two groups. Finally, for leptin, neither serum level nor gene expression was different between the two groups. Serum adiponectin level was the only predictor of nonalcoholic steatohepatitis (NASH) in this study (P=0.024). Conclusions: Obese patients with insulin resistance have decreased serum adiponectin and increased serum resistin. Additionally, adiponectin gene expression is also decreased in the adipose tissue of these patients. This low level of adiponectin expression may predispose patients to the progressive form of NAFLD or NASH.     

Lipoprotein Lipase but Not Hormone-Sensitive Lipase Activities Achieve Normality After Surgically Induced Weight Loss in Morbidly Obese Patients

Background  Although bariatric surgery is currently the most common practice for inducing weight loss in morbidly obese patients (BMI > 40 kg/m²), its effect on the lipid content of adipose tissue and its lipases (lipoprotein lipase [LPL] and hormone-sensitive lipase [HSL]) are controversial. Methods  We analyzed LPL and HSL activities and lipid content from plasma as well as subcutaneous (SAT) and visceral (VAT) adipose tissue of 34 morbidly obese patients (MO) before and after (6 and 12 months) Roux-en-Y gastric bypass surgery and compare the values with those of normal weight (control) patients. Results  LPL activity was significantly higher in MO (SAT = 32.9 ± 1.0 vs VAT = 36.4 ± 3.3 mU/g tissue; p < 0.001) than in control subjects (SAT = 8.2 ± 1.4 vs VAT = 6.8 ± 1.0 mU/g tissue) in both adipose depots. HSL activity had similar values in both types of tissue (SAT = 32.8 ± 1.6 and VAT = 32.9 ± 1.6 mU/g) of MO. In the control group, we found similar results but with lower values (SAT = 11.9 ± 1.4 vs VAT = 12.1 ± 1.4 mU/g tissue). Twelve months after surgery, SAT LPL activity diminished (9.8 ± 1.4 mU/g tissue, p < 0.001 vs morbidly obese), while HSL (46.6 ± 3.7 mU/g tissue) remained high. All lipids in tissue and plasma diminished after bariatric surgery except plasma nonesterified fatty acids, which maintained higher levels than controls (16 ± 3 vs 9 ± 0 mg/dL; p < 0.001, respectively). Conclusions  When obese patients lose weight, they lose not only part of the lipid content of the cells but also the capacity to store triacylglycerides in SAT depots. E. Pardina and A. Lecube contributed equally to this study. J.A. Baena-Fustegueras and J. Peinado-Onsurbe share senior authorship.     

SIRT1 Transcription Is Decreased in Visceral Adipose Tissue of Morbidly Obese Patients with Severe Hepatic Steatosis

Background  

Visceral adipose tissue is known to release greater amounts of adipokines and free fatty acids into the portal vein, being one of the most predictive factors of nonalcoholic fatty liver disease (NAFLD). Our study has the purpose to evaluate sirtuin 1 (SIRT1), adiponectin, Forkhead/winged helix (FOXO1), peroxisome proliferator-activated receptor (PPAR)γ1–3, and PPARβ/δ mRNA expression in morbidly obese patients in three different lipid depots: visceral (VAT), subcutaneous (SAT), and retroperitoneal (RAT). Recent studies suggest that SIRT1, a NAD⁺-dependent deacetylase, protects rats from NAFLD.     

Relationship Between Adiponectin and Left Atrium Size in Uncomplicated Obese Patients: Adiponectin, a Link Between Fat and Heart

Background  It is well known that obesity is a risk factor for severe cardiovascular complications, such as coronary heart disease, heart failure, stroke, venous thromboembolic disease, and atrial fibrillation. Left ventricle (LV) and left atrium (LA) enlargement is a characteristic feature of these patients with the consequent cardiovascular risk. Factors other than hemodynamic may influence LA remodeling. The aim of the study is to evaluate the relationship between adiponectin and LA size in uncomplicated obese patients. Methods  Seventy-four asymptomatic obese patients and an age- and sex-matched control group (N = 70) were recruited. A detailed clinical, echocardiographic, and analytical study was performed. Insulin resistance was assessed using the homeostasis model assessment for insulin resistance (HOMA-IR) method. Insulin sensitivity was assessed measuring serum total adiponectin concentrations. Results  Adiponectin levels were lower in the obese group (P < 0.001) and particularly so in those obese participants with enlarged LA (32%; P < 0.0005). LA sizes were higher in the obese group (P < 0.0005). Adiponectin displayed significant correlations with body mass index, glucose, insulin, high-density lipoprotein cholesterol, and triglyceride concentrations as well as HOMA-IR (P < 0.001 for all). Adiponectin displayed significant correlations with LV mass and LA size, diastolic and systolic cardiac volumes and diameters, and cardiac output (P < 0.001 for all). Adiponectin correlations with LA size (r = −0.429; P < 0.001) persisted after adjustment for HOMA-IR, age, sex, and LV mass. Conclusions  A novel inverse relationship between adiponectin and LA size independent of age, sex, insulin resistance, and LV mass appears in our series. Adiponectin could be a link between adipose tissue and the heart, having an influence on cardiac remodeling.     

The Early Effects of Weight Loss Surgery on Regional Adiposity

Background: Weight loss beyond 6 months following laparoscopic adjustable gastric banding (LAGB) is associated with a preferential mobilization of visceral adipose tissue and an improvement in insulin sensitivity in insulin resistant subjects. Because the rate of weight loss is greatest in the first 3 months after LAGB, we investigated the impact of LAGB on changes in regional lipid deposition and insulin sensitivity over this period. Methods: 10 female obese non-diabetic subjects underwent magnetic resonance (MR) imaging and spectroscopy before and 12 weeks after LAGB (using the Swedish band), for the quantification of abdominal subcutaneous and visceral adipose tissue areas and intrahepatic lipid. Fasting blood free fatty acids were analyzed. Insulin sensitivity was monitored by fasting insulin and homeostasis model assessment (HOMA). Results: Median weight loss 12 weeks after gastric banding was 9.5 kg [interquartile range (IQR): −16.5 to −6]. There were significant reductions in median abdominal subcutaneous (−20% [IQR: −24 to −13]) and visceral (−15% [IQR: −49 to −8]) adipose tissue depots as well as plasma free fatty acids (−34% [IQR: −79 to −8]). The amount of weight lost was directly proportional to the initial BMI (r=0.778; P=0.008). Visceral fat loss was proportional to initial visceral adiposity (r=0.80, P=0.01). There was no significant improvement in insulin sensitivity. Conclusion: Significant fat loss occurs 3 months after LAGB. The absence of a concurrent improvement in insulin sensitivity may reflect the relatively small reduction in visceral adipose tissue at this stage. Improvement in insulin sensitivity beyond 3 months after LAGB may be due to the continued loss of visceral adipose tissue.     

Relationship between the Upper Airway and Obstructive Sleep Apnea-Hypopnea Syndrome in Morbidly Obese Women

Background The authors studied changes in the upper airway in morbidly obese women and the relationship to sleep apnea-hypopnea syndrome (OSAS). Methods Patients underwent a cardiorespiratory polygraphic study, respiratory function test (spirometry, plethysmography, maximum inspiratory pressures and arterial blood gas analysis), and computed tomographic studies of the upper airway. Results 40 morbidly obese women being evaluated for bariatric surgery (mean age 39.6 ± 9.6 years old, BMI 48.7 ± 5.6 kg/m²) were studied. 37 women had OSAS, and 14 had severe OSAS. Results on respiratory function tests were normal. BMI and weight had a positive correlation with apnea-hypopnea index (AHI), apnea index (AI), desaturation index (DI), lowest oxygen saturation and CT90. Uvula diameter had a negative correlation with FEV₁, FVC, VC IN and a positive correlation with TLC. Retropharynx soft tissue at the retropalatal level had a negative correlation with FEV₁, FVC and VC IN. The oropharynx area at maximal inspiration (total lung capacity) obtained a negative correlation with the AHI (r = −0.423, P = 0.044), AI (r = −0.484, P = 0.042) and DI (r = −0.484, P = 0.019). Conclusions Prevalence of OSAS in morbidly obese women is very high. Our results show the significant correlation between BMI and AHI in morbidly obese women. Uvula diameter and retropharynx soft tissue are the upper airway parameters with higher relationship with pulmonary function. A reduction in the cross-sectional area of the airway at the level of the oropharynx could be related to the severity of OSAS in morbidly obese women.     

The FTO Obesity Gene. Genotyping and Gene Expression Analysis in Morbidly Obese Patients

BACKGROUND: Obesity has emerged as one of the most serious public health concerns in the twenty-first century. the fat mass and obesity associated gene (FTO) has been found to contribute to the risk of obesity in humans. Our aims in this study were to investigate the association of rs9939609 single nucleotide polymorphism (SNP) of the FTO gene with different obesity-related parameters, to assess the FTO gene expression in subcutaneous and visceral adipose tissues from morbidly obese and its correlations with other adipocytokine gene expressions. METHODS: The association between the rs9939609 FTO gene variant and obesity related parameters in 75 obese/morbidly obese adult patients and 180 subjects with body mass index (BMI) < 30 kg/m(2) (control group) was examined. Gene expression analyses: subcutaneous adipose tissue samples were obtained from 52 morbidly obese and five subjects with BMI < 30 kg/m(2). Visceral adipose tissue was also obtained from 35 morbidly obese patients. Weight, height, BMI, SBP, DBP, fasting glucose, lipid profile, proinsulin, insulin, leptin, and adiponectin (RIA) of patients were also obtained. Insulin resistance by HOMA(IR). rs9939609 of FTO genotyping using allele discrimination in real-time PCR. Genomic study of RNA extraction of adipose tissue and real-time PCR (RT-PCR) of adipocytokines and a housekeeping gene were quantified using TaqMan probes. Relative quantification was calculated using the DeltaDelta Ct formula. RESULTS: The minor-(A) allele frequency of rs9939609 FTO gene in the whole population was 0.39. A strong association between this A allele and obesity was found, even after age-sex adjustment (p = 0.013). We found higher levels of FTO mRNA in subcutaneous adipose tissue from morbidly obese than in the control group (p = 0.021). FTO gene expression was lower in visceral than in subcutaneous adipose depot. However, this finding did not reach the level of statistical significance. A negative correlation between subcutaneous FTO gene expression and serum triglyceride levels and a positive correlation with leptin, perilipin, and visfatin gene expressions was found. In the visceral adipose tissue, these positive correlations were statistically significant only for perilipin. CONCLUSIONS: Our results show: (1) A strong association between rs9939609 SNP of the FTO gene variant and obesity in Spanish morbidly obese adult patients; (2) positive correlations between FTO mRNA and leptin, perilipin, and visfatin gene expressions in subcutaneous adipose tissue; (3) FTO and perilipin gene expressions were positively correlated in visceral fat depot. Overall these results may suggest a role of FTO in the regulation of lipolysis as well as in total body fat rather in fat distribution patterns.     

Plasma Protein Carbonyl and Thiol Stress Before and After Laparoscopic Gastric Banding in Morbidly Obese Patients

Background The aim of this study is to examine the relationship between oxidative plasma protein and thiol stress and weight loss after laparoscopic adjustable gastric banding (LAGB). Methods Plasma protein carbonyl (PCO) concentration as a marker of protein oxidation, plasma thiol (PSH) and erythrocyte glutathione concentration (GSH, major intracellular thiol), as an antioxidant and metabolic markers, such as Homeostatic Model Assessment – Insulin resistance (HOMA-IR), BMI and plasma lipids were determined in morbidly obese patients (n 22, mean age 34.7 ± 11 years, BMI 48.4 ± 6.4 kg/m²) at baseline and 1 and 6 months after operation. Baseline levels in patients were also compared with the levels in agematched controls (n 20, BMI 21.3 ± 1.8 kg/m²). Plasma PCO and thiols and erythrocyte GSH concentrations were determined spectrophotometrically. Results Plasma PCO were significantly higher and plasma and erythrocyte thiol concentrations were significantly lower in morbidly obese patients than in controls (for each comparison, P < 0.01). BMI, plasma triglycerides and HOMA-IR were positively correlated with plasma PCO and negatively correlated with plasma P-SH and erythrocyte GSH (for each comparison, P < 0.01). Plasma HDL-cholesterol levels were positively correlated with plasma erythrocyte GSH (r = 0.405, P < 0.01) and negative correlated with plasma PCO (r = −0.273, P < 0.01). One and 6 months after the LAGB operation, total weight loss was 13.2 ± 6.3 and 35.5 ± 7.5 kg, respectively. Plasma PCO concentrations were decreased and P-SH and erythrocyte GSH concentrations were elevated following weight loss (for each, P < 0.01). Only plasma P-SH levels were restored to the control levels 6 months after LAGB. Conclusions Obesity and insulin resistance appear to be associated with plasma protein oxidation and thiol concentrations. Protein and thiol oxidative stress was improved by weight loss after LAGB in the short-term.     

Impact of Gastric Banding on Plasma Adiponectin Levels

Background: Several endocrine abnormalities are reported in obesity. In an earlier study, we found that the changes in BMI following laparoscopic adjustable gastric banding (LAGB) were associated with changes in hormone profiles such as insulin and proinsulin. In the current study, we explored the changes in plasma adiponectin levels in morbidly obese subjects who lost abundant weight following LAGB. Methods: 23 adult morbidly obese patients (15 females), aged 21-56 years, were studied. Blood samples were collected before, and 6 and 14 months after LAGB. The plasma adiponectin levels were determined by commercial kit (B-Bridge International, Inc). Statistical analysis was based on one-way repeated measures ANOVA, followed by Student-NewmanKeuls post-hoc test. Regression model was used to look for predictors of adiponectin change after LAGB. Results: Mean BMI before surgery was 46.04±4.44 kg/m², and decreased significantly by 18% 6 months after surgery to 37.67±4.47 kg/m². BMI further decreased by 32% 14 months after surgery to a mean of 31.30±4.65 kg/m² (P =.000). The mean adiponectin level before surgery was 3997±1766 μg/ml, and increased significantly by 16% to 4763±1776 μg/ml 6 months after surgery, and to 6336±3292 μg/ml (37%) 14 months after surgery. Although BMI persistently decreased, while adiponectin persistently increased, BMI did not correlate with adiponectin. Conclusion: In morbidly obese patients who underwent LAGB, adiponectin levels persistently increased, probably due to the reduction of visceral fat mass. Adiponectin plasma increase was correlated with proinsulin levels prior to the surgery. The interaction between adiponectin, proinsulin and BMI change in morbid obesity merits further investigation.     

Restorative Proctocolectomy for Ulcerative Colitis: Impact on Lipid Metabolism and Adipose Tissue and Serum Fatty Acids

The aim of this prospective study was to evaluate the changes of the metabolism of circulating and storage lipids in patients with ulcerative colitis after restorative proctocolectomy. Fifteen consecutive patients and 15 sex- and age-matched healthy controls were enrolled. Disease activity, diet, inflammatory parameters, plasma lipoprotein concentrations, and fatty acids (FA) of serum phospholipids and of the subcutaneous adipose tissue were assessed at colectomy and at ileostomy closure. In ulcerative colitis patients, total cholesterol and docosahexaenoic acid were lower than in healthy subjects (p < 0.01 and p < 0.05). The median interval between colectomy and ileostomy closure was 6 (range 2–9) months. During that interval, the inflammatory parameters improved, high-density lipoproteins (HDL) cholesterol increased (p < 0.01), and low-density (LDL) cholesterol decreased (p = 0.01). At ileostomy closure, serum arachidonic acid levels were increased (p = 0.04), whereas serum oleic acid level was decreased (p = 0.02). In this interval, no significant alteration, either in serum n-3 FA precursors or in the FA of subcutaneous adipose tissue, was observed. The increase of serum arachidonic acid after colectomy might suggest a lower utilization for inflammatory process. The reduction of LDL cholesterol is an index of malabsorption probably due to the accelerated transit and to the exclusion of the terminal ileum caused by the covering ileostomy. Presented at the 48th annual meeting of the Society for Surgery of the Alimentary tract (Digestive Disease Week) May 19–24, 2007 Washington, DC, USA, as a poster.     

Influence of Waist Circumference on the Metabolic Risk Associated with Impaired Fasting Glucose: Effect of Weight Loss after Gastric Bypass

Background Impaired fasting glucose (IFG) is a prediabetic state defined as a fasting plasma glucose (FPG) between 100 and 125 mg/dl. However, individuals in this group do not exhibit the same atherogenic risk. Methods The atherogenic profile of subjects with IFG >110 mg/dl (IFG110, n = 96) or <110 mg/dl (IFG100, n = 131) were compared and the potential differential impact of the waist circumference analyzed. In addition, the same clinical variables were measured in 18 morbidly obese patients (8 males, 10 females; BMI 45.3 ± 1.9 kg/m²) before and after weight loss following Roux-en-Y gastric bypass (RYGBP), in order to analyze the influence of the reduction in waist circumference on the improvement of the metabolic risk factors. Results Individuals in the IFG110 group showed decreased HDL-cholesterol levels together with an increased total cholesterol to HDL ratio (TC/HDL), accompanied by elevated homocysteine concentrations and white blood cell (WBC) count, and higher waist circumference (P < 0.05 for all). Significant correlations between waist circumference and HDL-cholesterol (r = −0.200, P < 0.05), TC/HDL (r = 0.190, P < 0.05), WBC count (r = 0.299, P < 0.05), and QUICKI (r = −0.375, P < 0.0001) were observed. An almost 3-fold increase in the prevalence of T2DM in subjects in the IFG110 group as compared to IFG100 was observed. In the group of patients who underwent RYGBP, the reduction in waist circumference was significantly associated with the improvement in insulin sensitivity as evidenced by the QUICKI index (r = −0.582, P < 0.05) and the reduction in TC/HDL (r = 0.595, P < 0.05). Conclusion Waist circumference is related to metabolic risk factors associated with increased levels of IFG. Our data support that individuals with IFG >110 mg/dl and a high waist circumference should undergo an OGTT to exclude the presence of diabetes.     

Lipopolysaccharide-Binding Protein Plasma Levels and Liver TNF-Alpha Gene Expression in Obese Patients: Evidence for the Potential Role of Endotoxin in the Pathogenesis of Non-Alcoholic Steatohepatitis

Background Some lines of evidence suggest that endotoxin may induce non-alcoholic steatohepatitis (NASH) in a background of fatty liver. However, a clear association between increased endotoxemia and development of steatohepatitis in obese patients has not been confirmed. We aim to assess the endotoxemic state of patients with non-alcoholic fatty liver disease (NAFLD) and its relationship with the liver expression of TNF-α and the presence of NASH. Methods Prospective study comprising 40 patients with morbid obesity who were diagnosed with NAFLD. Blood samples and liver biopsies were collected. Endotoxemia was assessed by the evaluation of circulating level of LPS-binding protein (LBP). Plasma levels of LBP and TNF-α were assessed by ELISA. The expression of TNF-α in liver tissue was evaluated by real-time PCR. Histological examination was performed to evaluate the presence of steatosis or NASH. Results Levels of LBP were increased in obese patients with NAFLD. In addition, plasma level of LBP was increased in patients with steatohepatitis (14.2 ± 3.9 μg/mL) when compared with patients with simple steatosis (11.5 ± 3.2 μg/mL), P = 0.041.The TNF-α mRNA expression in liver tissue was significantly higher in patients with NASH.This increment correlated with the rise in plasma levels of LBP (r = 0.412, P = 0.036). Conclusion NAFLD patients have elevated plasma levels of LBP and they are further increased in patients with NASH. This increase is related to a rise in TNF-α gene expression in the hepatic tissue which supports a role for endotoxemia in the development of steatohepatitis in obese patients.     

Serum Lipid Profile and Plasma Fatty Acids Levels in Hemodialysis Pediatric Patients-Possible Deficiency of Essential Fatty Acids

Polyunsaturated fatty acids (PUFA) are reported to be associated with atherosclerotic and inflammatory diseases because they are the major components of the cytoplasmic membrane and are the precursor fatty acids for prostaglandins and leukotrienes. Aim of this study was to identify PUFA profile (PUFAp) in children with end stage renal disease (ESRD) on hemodialysis (HD). And study its relationship with known cardiovascular and arteriosclerotic risk factors. We examined 44 pediatric HD patients (mean age 11 ± 3.36 years). Plasma lipid profile, plasma fatty acid pattern, serum albumin and hemoglobin were studied in these children. Triglyceride levels were increased in the plasma of ESRD patients compared to the healthy subjects. Plasma PUFA decreased whereas behanic acid (saturated fatty acid) increased in ESRD patients. A lower level of eicosapentaenoic acid was revealed in HD patients with cardiomyopathy (HD-CAD) than those without cardiovascular disease(HD-norm) (0.20 ± 0.01 μ/mL vs. 0.88 ± 0.12 μ/mL, P = 0.01). An inverse correlation was found between the linoleic acid level and serum TG level in children on HD (r = −0.54, P = 0.03). A positive correlation was found between plasma arachidonic acid level and serum albumin (r = 0.86, P = 0.003). A significant positive correlation was revealed between plasma eicosapentaenoic acid concentration and serum hemoglobin level (r = −0.64, P = 0.04). Saturated acid was negatively correlated with serum albumin (r = −0.70, P = 0.03). Children under regular hemodialysis evidence significant abnormalities in serum fatty acid levels together with triglyceride abnormalities, a finding that might be relevant to the risk of cardiovascular disease in this setting.     

Evaluation of activity,chronicity and tubulointerstitial indices for childhood lupus nephritis

Few data exist on use of the National Institutes of Health (NIH) activity index (AI) and chronicity index (CI) in childhood lupus nephritis (LN). A tubulointerstitial activity index (TIAI) has been derived but not validated. We evaluated clinicopathologic correlations of the AI, CI and TIAI in children with LN who had undergone initial renal biopsy (n = 25, age 12.4 ± 2.7 years, biopsy 1) and 1 year after treatment (n = 15, biopsy 2). The TIAI correlated with the AI at biopsy 1 (r = 0.76, P = 0.001) and biopsy 2 (r = 0.52, P = 0.05), but not with CI scores. Mean AI and CI scores changed substantially from biopsy 1 to biopsy 2 (P < 0.05), but TIAI scores did not. Higher AI and TIAI scores correlated with proteinuria at both biopsies (r = 0.51–0.76, P < 0.05); CI scores correlated with estimated creatinine clearance (r = 0.46–0.58, P < 0.05). Improved AI score from biopsy 1 to biopsy 2 was associated with decrease in proteinuria. These results suggest that the AI and CI are useful in childhood LN. The TIAI may be a valid measure to evaluate the tubulointerstitium, but research is needed to define its responsiveness to change with therapy.     

Adiponectin and Peak Bone Mass in Men: A Cross-Sectional, Population-Based Study

Adiponectin, a protein classically known to be secreted by adipocytes, is also secreted by bone-forming cells. Results of previous studies have been contradictory as to whether serum adiponectin and bone mineral density (BMD) are associated. The aim of this study was to investigate a possible association between serum adiponectin and BMD in young, healthy men at a time of peak bone mass. BMD in the femoral neck, total hip, and lumbar spine were measured in this population-based cross-sectional study of 700 men aged 20–29 years participating in the Odense Androgen Study. Magnetic resonance imaging of femoral cortical thickness and bone marrow size was performed in a subsample of 363 participants. The associations between serum adiponectin and various bone measures were investigated by means of regression analyses with adjustment for potential confounding variables. An inverse association was found between serum adiponectin and total hip BMD and a direct between adiponectin and femoral bone marrow size (r = −0.092; P = 0.036 and r = 0.164; P = 0.003, respectively). Femoral muscle size may, at least in part, explain the association between adiponectin and total hip BMD. Serum adiponectin was inversely associated with total hip BMD in men at the time of peak bone mass, but this association may be explained by factors related to muscle size and function. The observed association between adiponectin and femoral bone marrow size was retained even after adjustment for potential covariates.     

Serum Magnesium Status After Gastric Bypass Surgery in Obesity

Background  Roux-en-Y gastric bypass (RYGBP) has become a common surgical procedure to treat morbid obesity. Furthermore, it strongly reduces the incidence of type 2 diabetes and mortality. However, there is scant information on how magnesium status is affected by RYGBP surgery. Previous bariatric surgery methods, like jejunoileal bypass, are associated with hypomagnesemia. Methods  Twenty-one non-diabetic morbidly obese patients who underwent RYGBP were evaluated before and 1 year after surgery and compared to a matched morbidly obese control group regarding serum magnesium. Groups were matched regarding weight, BMI, abdominal sagittal diameter and fasting glucose, blood pressure, and serum magnesium concentrations before surgery in the RYGBP group. Results  The serum magnesium concentrations increased by 6% from 0.80 to 0.85 mmol/l (p = 0.019) in the RYGBP group while a decrease by 4% (p = 0.132) was observed in the control group. The increase in magnesium concentration at the 1-year follow-up in the RYGBP group was accompanied by a decreased abdominal sagittal diameter (r ² = 0.32, p = 0.009), a lowered BMI (r ² = 0.28, p = 0.0214), a lowered glucose concentration (r ² = 0.28, p = 0.027) but not by a lowered insulin concentration (p = 0.242), a lowered systolic (p = 0.789) or a lowered diastolic (p = 0.785) blood pressure. Conclusion  RYGBP surgery in morbidly obese subjects is characterized by reduced visceral adiposity, lowered plasma glucose, and increased circulating magnesium concentrations. The inverse association between lowered central obesity, lowered plasma glucose and increased magnesium concentrations, needs further detailed studies to identify underlying mechanisms.