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Colorectal cancer (CRC) is one of the most common malignancies in the Western world and intestinal dysbiosis might contribute to its pathogenesis. The mucosal colon microbiome and C-C motif chemokine 2 (CCL2) were investigated in 20 healthy controls (HC) and 20 CRC patients using 16S rRNA sequencing and immunoluminescent assay, respectively. A total of 10 HC subjects were classified as overweight/obese (OW/OB_HC) and 10 subjects were normal weight (NW_HC), 15 CRC patients were classified as OW/OB_CRC and 5 patients were NW_CRC. Results: Fusobacterium nucleatum and Escherichia coli were more abundant in OW/OB_HC than in NW_HC microbiomes. Globally, Streptococcus intermedius, Gemella haemolysans, Fusobacterium nucleatum, Bacteroides fragilis and Escherichia coli were significantly increased in CRC patient tumor/lesioned tissue (CRC_LT) and CRC patient unlesioned tissue (CRC_ULT) microbiomes compared to HC microbiomes. CCL2 circulating levels were associated with tumor presence and with the abundance of Fusobacterium nucleatum, Bacteroides fragilis and Gemella haemolysans. Our data suggest that mucosal colon dysbiosis might contribute to CRC pathogenesis by inducing inflammation. Notably, Fusobacterium nucleatum, which was more abundant in the OW/OB_HC than in the NW_HC microbiomes, might represent a putative link between obesity and increased CRC risk.

Purpose. Fat mass and obesity-related (FTO) rs9939609 polymorphism has a role in body mass index (BMI) increase and in predisposing to metabolic syndrome (MetS). Our aim was to investigate if a very light physical activity could counteract weight gain and MetS in obese subjects bearing the rs9939609 FTO polymorphism from Southern Italy. Methods. Data of fitness components, anthropometry, clinical-biochemical parameters and FTO polymorphism in 78 unrelated morbid obese subjects from Southern Italy (15-30 years) were examined. Physical activity energy expenditure was monitored by a SenseWear Pro 3 Armband for 24 h/day for two consecutive weekdays in all enrolled individuals. Results. Sedentary obese subjects had higher waist circumference (124.8 vs 117.9 cm, P

The gut microbiota may have an impact on obesity. To date, the majority of studies in obese patients reported microbiota composition in stool samples. The aim of this study was to investigate the duodenal mucosa dysbiosis in adult obese individuals from Campania, a region in Italy with a very high percentage of obese people, to highlight microbial taxa likely associated with obesity. Duodenum biopsies were taken during upper gastrointestinal endoscopy in 19 obese (OB) and 16 lean control subjects (CO) and microbiome studied by 16S rRNA gene sequencing. Duodenal microbiome in our groups consisted of six phyla: Proteobacteria, Firmicutes, Actinobacteria, Fusobacteria, Bacteroidetes and Acidobacteria. Proteobacteria (51.1% vs. 40.1%) and Firmicutes (33.6% vs. 44.9%) were significantly (p < 0.05) more and less abundant in OB compared with CO, respectively. Oribacterium asaccharolyticum, Atopobium parvulum and Fusobacterium nucleatum were reduced (p < 0.01) and Pseudomonadales were increased (p < 0.05) in OB compared with CO. Receiver operating characteristic curve analysis showed Atopobium and Oribacterium genera able to discriminate with accuracy (power = 75% and 78%, respectively) OB from CO. In conclusion, increased Proteobacteria and decreased Firmicutes (Lachnospiraceae) characterized the duodenal microbiome of obese subjects. These data direct to further studies to evaluate the functional role of the dysbiotic-obese-associated signature.

Nutritional imbalance and metabolic alterations associated with maternal obesity during pregnancy predispose offspring to obesity and/or to type 2 diabetes, but the mechanisms underlying these effects are still obscure. In this context, we evaluated whether the two main energy-producing pathways (glycolysis and mitochondrial oxidative phosphorylation) are impaired in obesity during pregnancy thus contributing to metabolic intrauterine alterations. Specifically, we studied metabolic abnormalities in the intrauterine life of newborns using stem cells isolated from amnion and umbilical cord (hA- and hUC-MSCs). We isolated, at delivery, neonatal hUC-MSCs from 13 obese (Ob) and 10 normal weight control (Co) women (prepregnancy body mass index >30 and

Obesity is a multifactorial disorder, and the gut microbiome has been suggested to contribute to its onset. In order to better clarify the role of the microbiome in obesity, we evaluated the metatranscriptome in duodenal biopsies from a cohort of 23 adult severely obese and lean control subjects using next generation sequencing. Our aim was to provide a general picture of the duodenal metatranscriptome associated with severe obesity. We found altered expressions of human and microbial genes in the obese compared to lean subjects, with most of the gene alterations being present in the carbohydrate, protein, and lipid metabolic pathways. Defects were also present in several human genes involved in epithelial intestinal cells differentiation and function, as well as in the immunity/inflammation pathways. Moreover, the microbial taxa abundance inferred by our transcriptomic data differed in part from the data that we previously evaluated by 16S rRNA in 13/23 individuals of our cohort, particularly concerning the Firmicutes and Proteobacteria phyla abundances. In conclusion, our pilot study provides the first taxonomic and functional characterization of duodenal microbiota in severely obese subjects and lean controls. Our findings suggest that duodenal microbiome and human genes both play a role in deregulating metabolic pathways, likely affecting energy metabolism and thus contributing to the obese phenotype.

Background. Laparoscopic adjustable gastric banding (LAGB) results in significant lasting weight loss and improved metabolism in obese patients. To evaluate whether epigenetic factors could concur to these benefits, we investigated the subcutaneous adipose tissue (SAT) microRNA (miRNA) profile before (T0) and three years (T1) after LAGB in three morbidly obese women. Case Reports. SAT miRNA profiling, evaluated by TaqMan Array, showed four downexpressed (miR-519d, miR-299-5p, miR-212, and miR-671-3p) and two upexpressed (miR-370 and miR-487a) miRNAs at T1 versus T0. Bioinformatics predicted that these miRNAs regulate genes belonging to pathways associated with the cytoskeleton, inflammation, and metabolism. Western blot analysis showed that PPAR-alpha, which is the target gene of miR-519d, increased after LAGB, thereby suggesting an improvement in SAT lipid metabolism. Accordingly, the number and diameter of adipocytes were significantly higher and lower, respectively, at T1 versus T0. Bioinformatics predicted that the decreased levels of miR-212, miR-299-5p, and miR-671-3p at T1 concur in reducing SAT inflammation. Conclusion. We show that the miRNA profile changes after LAGB. This finding, although obtained in only three cases, suggests that this epigenetic mechanism, by regulating the expression of genes involved in inflammation and lipid metabolism, could concur to improve SAT functionality in postoperative obese patients.

Maternal obesity increases the risk of obesity and/or obesity-related diseases in the offspring of animal models. The aim of this study was to identify metabolic dysfunctions that could represent an enhanced risk for human obesity or obesity-related diseases in newborn or in adult life, similar to what occurs in animal models. To this aim, we studied the proteome of 12 obese (Ob-) and 6 non-obese (Co-) human amniotic mesenchymal stem cells (hA-MSCs) obtained from women at delivery by cesarean section (pre-pregnancy body mass index [mean ± SD]: 42.7 ± 7.7 and 21.3 ± 3.3 kg/m2, respectively). The proteome, investigated by two-dimensional fluorescence difference gel electrophoresis/mass spectrometry, revealed 62 differently expressed proteins in Ob- vs Co-hA-MSCs (P

Mitochondrial DNA (mtDNA) haplogroups have been associated with the expression of mitochondrial-related diseases and with metabolic alterations, but their role has not yet been investigated in morbid obese Caucasian subjects. Therefore, we investigated the association between mitochondrial haplogroups and morbid obesity in patients from southern Italy. The mtDNA D-loop of morbid obese patients (n=500; BMI > 40 kg/m2) and controls (n=216; BMI < 25 kg/m2) was sequenced to determine the mtDNA haplogroups. The T and J haplogroup frequencies were higher and lower, respectively, in obese subjects than in controls. Women bearing haplogroup T or J had twice or half the risk of obesity. Binomial logistic regression analysis showed that haplogroup T and systolic blood pressure are risk factors for a high degree of morbid obesity, namely, BMI > 45 kg/m2and in fact together account for 8% of the BMI. In conclusion, our finding that haplogroup T increases the risk of obesity by about two-fold, suggests that, besides nuclear genome variations and environmental factors, the T haplogroup plays a role in morbid obesity in our study population from southern Italy.

Maternal obesity is associated to increased fetal risk of obesity and other metabolic diseases. Human amniotic mesenchymal stem cells (hA-MSCs) have not been characterized in obese women. The aim of this study was to isolate and compare hA-MSC immunophenotypes from obese (Ob-) and normal weight control (Co-) women, to identify alterations possibly predisposing the fetus to obesity. We enrolled 16 Ob- and 7 Co-women at delivery (mean/SEM prepregnancy body mass index: 40.3/1.8 and 22.4/1.0 kg/m2, respectively), and 32 not pregnant women. hA-MSCs were phenotyped by flow cytometry; several maternal and newborn clinical and biochemical parameters were also measured. The expression of membrane antigen CD13 was higher on Ob-hA-MSCs than on Co-hA-MSCs (P = 0.005). Also, serum levels of CD13 at delivery were higher in Ob- versus Co-pregnant women and correlated with CD13 antigen expression on Ob-hA-MSCs (r2 = 0.84, P < 0.0001). Adipogenesis induction experiments revealed that Ob-hA-MSCs had a higher adipogenic potential than Co-hA-MSCs as witnessed by higher peroxisome proliferator-activated receptor gamma and aP2 mRNA levels (P = 0.05 and P = 0.05, respectively), at postinduction day 14 associated with increased CD13 mRNA levels from baseline to day 4 postinduction (P < 0.05). Adipogenesis was similar in the two sets of hA-MSCs after CD13 silencing, whereas it was increased in Co-hA-MSCs after CD13 overexpression. CD13 expression was high also in Ob-h-MSCs from umbilical cords or visceral adipose tissue of not pregnant women. In conclusion, antigen CD13, by influencing the adipogenic potential of hA-MSCs, could be an in utero risk factor for obesity. Our data strengthen the hypothesis that high levels of serum and MSC CD13 are obesity markers.

ObjectiveAdiponectin is an adipocytokine that exerts beneficial effects on obesity and related disorders by two receptors (ADIPORs). Adiponectin is produced as a monomer that circulates in serum as different oligomers. The oligomerization state and the tissue expression of adiponectin and ADIPORs are linked to its biological activities. In this study, the levels of total adiponectin and its oligomers were evaluated in relation to obesity and surgical weight loss. The expression of adiponectin and ADIPORs was analyzed in visceral and subcutaneous adipose tissues of obese patients.Design and methodsIn 25 obese patients and 44 age- and sex-matched controls, the serum levels of adiponectin and its oligomers were measured and compared by ELISA, western blotting, and gel filtration. The expression of adiponectin and ADIPORs in both adipose tissues was evaluated by real-time quantitative PCR and western blotting.ResultsThe amount of each adiponectin oligomer, including the monomer, increases after weight loss. The reduced circulating levels of adiponectin and its oligomers are not associated with the adipose tissue depot-specific expression of adiponectin and ADIPORs.ConclusionsOur results suggest that in patients, adiposity is associated with the serum concentrations of adiponectin and its oligomers but not with adipose tissue depot-specific expression of adiponectin and ADIPORs. In particular, the increase in adiponectin monomer levels could probably be related to the improvement of the whole-body energy metabolism then being involved in the improvement of adipose tissue function after weight loss. This work indicates the importance of assessing the whole adiponectin oligomeric profile as further potential indicators of adipose tissue functions in obesity.

Adipose tissues show selective gene expression patterns, to whom microRNAs (miRNAs) may contribute. We evaluated in visceral adipose tissue (VAT) from obese and nonobese females, both miRNA and protein expression profiles, to identify miRNA/protein target pairs associated with obesity (metabolic pathways miRNA-deregulated during obesity). Obese and nonobese females [BMI 42.2 ± 1.6 and 23.7 ± 1.2 kg/m(2) (mean ± SEM), respectively] were enrolled in this study. Notably, most miRNAs were down-expressed in obese tissues, whereas most of the proteins from the investigated spots were up-expressed. Bioinformatics integration of miRNA expression and proteomic data highlighted two potential miRNA/protein target pairs: miR-141/YWHAG (tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein, gamma polypeptide) and miR-520e/RAB11A (Ras-related protein RAB-11A); the functional interaction between these miRNAs and their target sequences on the corresponding mRNAs was confirmed by luciferase assays. Both RAB11A and YWHAG proteins are involved in glucose homeostasis; YWHAG is also involved in lipid metabolism. Hence, the identified miRNA/protein target pairs are potential players in the obese phenotype.

"At-risk" severely obese subjects are characterized by insulin resistance, and higher visceral fat and plasma lipid levels compared with metabolically healthy obese (MHO) subjects, although both groups have a high BMI and fat mass. The aim of this study was to measure several serum adipokines and gastrointestinal hormones in a young severely obese population from Southern Italy to identify biochemical markers of the "at-risk" insulin-resistant obese profile. We studied 160 unrelated white young adults (mean age = 25.2 years, mean BMI = 44.9 kg/m(2), 65% women) affected by obesity for at least 5 years. Serum concentrations of glucagon, ghrelin, gastric inhibitory peptide, glucagon like peptide-1, interleukin-6, tumor necrosis factor α, leptin, adiponectin, adipsin, and visfatin were measured. The leptin/adiponectin (L/A) ratio and fatty liver index (FLI) were calculated. We found a prevalence of 21.3% of MHO patients in our young severely obese patients. At univariate analysis, the "at-risk" group had higher mean levels of BMI (P < 0.0001), leptin (P = 0.039, men) and the L/A ratio (P = 0.003), and lower mean levels of visfatin (P = 0.026) than the MHO group. The L/A ratio, serum triglycerides, and male sex were significantly associated with "at-risk" obesity and accounted for 19.5% of insulin resistance at multivariate analysis. In conclusion, we demonstrate that a high serum L/A ratio and high levels of serum triglycerides may be markers of "at-risk" obesity, independent of waist circumference (WC) and BMI, in young severely obese population.

Brown adipose tissue, where Uncoupling Protein 1 (UCP1) activity uncouples mitochondrial respiration, is an important site of facultative energy expenditure. This tissue may normally function to prevent obesity. Our aim was to investigate by sequence analysis the presence ofUCP1gene variations that may be associated with obesity. We studied 100 severe obese adults (BMI > 40 kg/m2) and 100 normal-weight control subjects (BMI range = 19–24.9 kg/m2). We identified 7 variations in the promoter region, 4 in the intronic region and 4 in the exonic region. Globally, 72% of obese patients boreUCP1polymorphisms. AmongUCP1variants, g.IVS4−208T>G SNP was associated with obesity (OR: 1.77; 95% CI = 1.26–2.50;P=.001). Further, obese patients bearing the g.−451C>T (CT+TT) or the g.940G>A (GA+AA) genotypes showed a higher BMI than not polymorphic obese patients (P=.008andP=.043, resp.). In conclusion,UCP1SNPs could represent “thrifty” factors that promote energy storage in prone subjects.

Background: Severe obesity is a major worldwide public health concern affecting 0.5–5% of the adult population. Adiponectin (Acpr30), an adipokine secreted from adipocytes, shows pleiotropic beneficial effects on obesity and related disorders. In this study, sequence analysis of Acpr30 gene (ACDC) was performed in a highly selected population of severely obese young adult patients from Southern Italy to investigate the associations between polymorphisms in the ACDC gene and the development of severe obesity concomitantly with other features of the metabolic syndrome. Methods: The ACDC gene was analyzed by direct sequencing in the severely obese patients (n = 220) and compared to healthy controls (n = 116). The associations between the ACDC gene single-nucleotide polymorphisms (SNPs) and the levels of serum Acpr30 as well as the correlation with the presence of severe obesity jointly associated with other features of the metabolic syndrome were also investigated. Total serum Acpr30 concentrations were measured by the ELISA method. Results: ACDC gene molecular screening revealed the presence of previously described SNPs and a new nucleotide alteration, c.355T>G, leading to a protein variant, p.L119V. Measurement of serum concentration of Acpr30 demonstrated lower levels of Acpr30 in the obese population compared to controls (30.5 ± 28.3 vs. 43.9 ± 35.7 μg/ml, p < 0.01); in particular, significantly lower Acpr30 concentrations were observed in obese patients bearing c.–11377C>G SNP CG+GG genotypes than in those with CC genotype (22.9 ± 20.5 vs. 33.1 ± 29.4 μg/ml, p < 0.05). Conclusions: Our results confirmed that low serum levels of Acpr30 are related to severe obesity and a difference in protein expression is associated with variants in ACDC gene promoter region.

To evaluate the prevalence of β3-adrenergic receptor (ADRB3) Trp64Arg polymorphism and its relationship with the metabolic syndrome in severe obesity. Cross-sectional outpatients study. In 265 (100 men) severely obese non-diabetic subjects and 78 (25 men) healthy volunteers, genomic DNA was isolated from peripheral leukocytes. In obese patients, plasma concentrations of leptin, lipids, glucose and insulin, the homeostasis model assessment index and blood pressure have been measured. The Trp64Arg mutation was identified with the real-time TaqMan method. Neither genotype distribution nor allele frequency differed between the two groups. The metabolic syndrome prevalence was 59% in obese subjects, and was higher in men than in women (65 vs 55%: P=0.03). The body mass index (BMI) was related to age tertiles (β=0.08; P

Background: The genetic characterization of obese individuals could clarify the molecular mechanisms underlying body weight regulation and lead to targeted therapy. Here we report variants of the proopiomelanocortin (POMC) and melanocortin receptor 4 (MC4R) genes detected in severely obese adults living in southern Italy. Methods: A total of 196 unrelated nondiabetic severely obese individuals [111 females and 85 males; mean (SD) age, 32.2 (11.5) years; mean body mass index, 48.8 (8.1) kg/m2] and 100 normal-weight healthy volunteers (34 males and 66 females) entered the study. POMC and MC4R were genotyped by sequencing analysis. Leptin, insulin, glucose, and the lipid profile were measured in fasting serum samples. We used the protein truncation test to verify the stop-codon mutation. Anthropometric measurements, sitting blood pressure, and heart rate were also recorded. Results: Of the obese participants, 1.5% had mutations in POMC exon 3 (new mutations, P231L and E244X; known, R236G) and 2.5% had MC4R mutations (new mutations, W174C, Q43X, S19fsX51, and I317V; known, A175T). These mutations were not present in the controls. Gene polymorphisms were identified in similar percentages of severely obese and nonobese individuals, i.e., respectively, 52.5% and 51% (POMC) and 1% and 2% (MC4R). Conclusions: We detected 2 new POMC mutations and 4 new MC4R mutations in a large number of severely obese adults living in southern Italy. These mutations, not present in normal-weight individuals, are further evidence that defects in the melanocortin pathway are related to severe obesity.

Background and aims: Non-alcoholic fatty liver disease (NAFLD) and metabolic syndrome (MS) are well-rec- ognized complications of obesity. This study was designed to evaluate the role of the UCP1 -3826 A>G polymorphism, adiponectin levels, leptin/adiponectin ratio (L/A), and main biochemical parameters in 102 unrelated severely obese adults (61 females and 41 males, median body mass index (BMI) = 47.8 kg/m2) with NAFLD, with (MS+) or without MS (MS-) from Southern Italy. Subject and methods: The UCP1 polymorphism was tested by the TaqMan method, main bio- chemical parameters by routinary methods, adiponectin, and leptin serum levels by enzyme-linked immunosorbent assay. MS was diagnosed according to the American Heart Association criteria, liver steatosis was detected by ultra- sound. Results: MS was present in 53% male and 66% fe- male obese patients. Only total cholesterol (p=0.04 males and p=0.002 females) and L/A ratio (p=0.03 males) differed between MS+ and MS- obese patients. At multivariate anal- ysis, severe liver steatosis was significantly associated with: UCP1 (AG+GG) genotypes (odds ratio-confidence interval (OR-CI): 4.25; 1.12-16.13), MS (OR-CI: 8.47; 1.78-40.25), low adiponectin levels (OR-CI: 0.92; 0.87-0.98), high alanine aminotransferase levels (OR-CI: 1.03; 1.00-1.06), age (OR- CI: 1.08; 1.00-1.15), and male gender (OR-CI: 10.78; 1.61- 71.96). Conclusion: In addition to traditional factors, total cholesterol and L/A ratio appear to contribute to MS char- acterization in severe obesity. Furthermore, the UCP1 (AG+GG) genotypes and low adiponectin levels could pre- dispose to a more severe liver steatosis independently of MS presence. Based on our data, polymorphic UCP1 (AG+GG) obese patients with low adiponectin levels appear to be high-risk subjects for worsening of liver steatosis, a NAFLD, possibly requiring a second-step evaluation by liv- er biopsy. (J. Endocrinol. Invest. 32: 525-529, 2009) ©2009, Editrice Kurtis