Validation in type 2 diabetes of a metabolomic signature of all-cause mortality.

CONTEXT: Mortality in type 2 diabetes is twice that of the normoglycemic population. Unravelling biomarkers that identify high-risk patients for referral to the most aggressive and costly prevention strategies is needed. OBJECTIVE: To validate in type 2 diabetes the association with all-cause mortality of a 14-metabolite score (14-MS) previously reported in the general population and whether this score can be used to improve well-established mortality prediction models. METHODS: This is a sub-study consisting of 600 patients from the "Sapienza University Mortality and Morbidity Event Rate" (SUMMER) study in diabetes, a prospective multicentre investigation on all-cause mortality in patients with type 2 diabetes. Metabolic biomarkers were quantified from serum samples using high-throughput proton nuclear magnetic resonance metabolomics. RESULTS: In type 2 diabetes, the 14-MS showed a significant (p < 0.0001) association with mortality, which was lower (p < 0.0001) than that reported in the general population. This difference was mainly due to two metabolites (histidine and ratio of polyunsaturated fatty acids to total fatty acids) with an effect size that was significantly (p = 0.01) lower in diabetes than in the general population. A parsimonious 12-MS (i.e. lacking the 2 metabolites mentioned above) improved patient discrimination and classification of two well-established mortality prediction models (p < 0.0001 for all measures). CONCLUSIONS: The metabolomic signature of mortality in the general population is only partially effective in type 2 diabetes. Prediction markers developed and validated in the general population must be revalidated if they are to be used in patients with diabetes.

Saxagliptin/dapagliflozin is non-inferior to insulin glargine in terms of ß-cell function in subjects with latent autoimmune diabetes in adults: A 12-month, randomized, comparator-controlled pilot study.

AIM: To compare the efficacy and safety of saxagliptin/dapagliflozin and insulin glargine in people with latent autoimmune diabetes in adults (LADA). METHODS: In this phase 2b multicentre, open-label, comparator-controlled, parallel-group, non-inferiority study, we randomly assigned 33 people with LADA who had a fasting C-peptide concentration ≥0.2 nmol/L (0.6 ng/mL) to receive 1-year daily treatment with either the combination of saxagliptin (5 mg) plus dapagliflozin (10 mg) or insulin glargine (starting dose: 10 IU), both on top of metformin. The primary outcome was the 2-h mixed meal-stimulated C-peptide area under the curve (AUC), measured 12 months after randomization. Secondary outcomes were glycated haemoglobin (HbA1c) levels, change in body mass index (BMI), and hypoglycaemic events. RESULTS: In the modified intention-to-treat analysis, the primary outcome was similar in participants assigned to saxagliptin/dapagliflozin or to insulin glargine (median C-peptide AUC: 152.0 ng*min/mL [95% confidence interval {CI} 68.2; 357.4] vs. 122.2 ng*min/mL [95% CI 84.3; 255.8]; p for noninferiority = 0.0087). Participants randomized to saxagliptin/dapagliflozin lost more weight than those randomized to insulin glargine (median BMI change at the end of the study: -0.4 kg/m2 [95% CI -1.6; -0.3] vs. +0.4 kg/m2 [95% CI -0.3; +1.1]; p = 0.0076). No differences in HbA1c or in the number of participants experiencing hypoglycaemic events were found. CONCLUSIONS: Saxagliptin/dapagliflozin was non-inferior to glargine in terms of ß-cell function in this 12-month, small, phase 2b study, enrolling people with LADA with still viable endogenous insulin production. Weight loss was greater with saxagliptin/dapagliflozin, with no differences in glycaemic control or hypoglycaemic risk.

Dynamic Changes of BVRA Protein Levels Occur in Response to Insulin: A Pilot Study in Humans.

Biliverdin reductase-A (BVRA) is involved in the regulation of insulin signaling and the maintenance of glucose homeostasis. Previous research showed that BVRA alterations are associated with the aberrant activation of insulin signaling in dysmetabolic conditions. However, whether BVRA protein levels change dynamically within the cells in response to insulin and/or glucose remains an open question. To this aim, we evaluated changes of intracellular BVRA levels in peripheral blood mononuclear cells (PBMC) collected during the oral glucose tolerance test (OGTT) in a group of subjects with different levels of insulin sensitivity. Furthermore, we looked for significant correlations with clinical measures. Our data show that BVRA levels change dynamically during the OGTT in response to insulin, and greater BVRA variations occur in those subjects with lower insulin sensitivity. Changes of BVRA significantly correlate with indexes of increased insulin resistance and insulin secretion (HOMA-IR, HOMA-ß, and insulinogenic index). At the multivariate regression analysis, the insulinogenic index independently predicted increased BVRA area under curve (AUC) during the OGTT. This pilot study showed, for the first time, that intracellular BVRA protein levels change in response to insulin during OGTT and are greater in subjects with lower insulin sensitivity, supporting the role of BVR-A in the dynamic regulation of the insulin signaling pathway.

Reduced Lipopolysaccharide-Binding Protein (LBP) Levels Are Associated with Non-Alcoholic Fatty Liver Disease (NAFLD) and Adipose Inflammation in Human Obesity.

Lipopolysaccharide (LPS) and its binding protein LBP have emerged as potential contributors to the progression from overweight/obesity to overt metabolic diseases and NAFLD. While LPS is known to activate hepatocyte inflammation, thus contributing toward NAFLD development, the role of LBP is more intricate, and recent data have shown that experimental reduction in hepatic LBP promotes NAFLD progression. In this cross-sectional investigation, we evaluated circulating LBP in relation to obesity, NAFLD, visceral adipose tissue (VAT) inflammation, and type 2 diabetes (T2D). We recruited 186 individuals (M/F: 81/105; age: 47 ± 10.4 years; BMI: 35.5 ± 8.6 kg/m2); a subgroup (n = 81) underwent bariatric surgery with intra-operative VAT and liver biopsies. LBP levels were higher in obese individuals than non-obese individuals but were inversely correlated with the parameters of glucose metabolism. Reduced LBP predicted T2D independent of age, sex, and BMI (p < 0.001). LBP levels decreased across more severe stages of hepatosteatosis and lobular inflammation, and were inversely associated with VAT inflammation signatures. In conclusion, LBP levels are increased in obese individuals and are associated with a more favorable metabolic profile and lower NAFLD/NASH prevalence. A possible explanation for these findings is that hepatic LBP production may be triggered by chronic caloric excess and facilitate LPS degradation in the liver, thus protecting these individuals from the metabolic consequences of obesity.

Neurotensin Gene rs2234762 C>G Variant Associates with Reduced Circulating Pro-NT Levels and Predicts Lower Insulin Resistance in Overweight/Obese Children.

Neurotensin (NT) is a small protein implicated in the regulation of energy balance which acts as both a neurotransmitter in the central nervous system and as a gastrointestinal peptide. In the gut, NT is secreted after fat ingestion and promotes the absorption of fatty acids. The circulating levels of its precursor, pro-NT, predicts the presence and development of metabolic and cardiovascular diseases. Despite the extensive knowledge on the dynamic changes that occur to pro-NT = after fat load, the determinants of fasting pro-NT are unknown. The aim of this study was to determine the possible genetic regulation of plasma pro-NT. The NT gene (NTS) was sequenced for potential functional variants, evaluating its entire genomic and potentially regulatory regions, in DNA from 28 individuals, stratified by low and high pro-NT levels. The identified variant differently distributed in the two pro-NT subgroups was genotyped in a cohort of nine hundred and thirty-two overweight/obese children and adolescents. A total of seven sequence variations across the NTS gene, none of them located in coding regions, were identified. The rs2234762 polymorphism, sited in the NTS gene promoter, was statistically more frequent in the lowest pro-NTS level group. Carriers of the rs2234762 variant showed lower pro-NT levels, after adjusting for sex, age, BMI, triglycerides and the Tanner stage. Having NTS rs2234762 predicted less pronounced insulin resistance at the 6.5-year follow-up with OR: 0.46 (0.216-0.983), at the logistic regression analysis adjusted for age, sex and BMI. In conclusion, the NTS rs2234762 gene variant is a determinant of reduced circulating pro-NT levels in overweight and obese children, which predisposes this group to a more favorable metabolic profile and a reduced insulin resistance later in life, independently from metabolic confounders.

Reduced High-Density Lipoprotein Cholesterol Is an Independent Determinant of Altered Bone Quality in Women with Type 2 Diabetes.

Type 2 diabetes mellitus (T2DM) is associated with an increased fracture risk. Our study aimed to explore differences in bone alterations between T2DM women and controls and to assess clinical predictors of bone impairment in T2DM. For this observational case control study, we recruited 126 T2DM female patients and 117 non-diabetic, age- and BMI-comparable women, who underwent clinical examination, routine biochemistry and dual-energy X-ray absorptiometry (DXA) scans for bone mineral density (BMD) and trabecular bone score (TBS) assessment-derived indexes. These were correlated to metabolic parameters, such as glycemic control and lipid profile, by bivariate analyses, and significant variables were entered in multivariate adjusted models to detect independent determinants of altered bone status in diabetes. The T2DM patients were less represented in the normal bone category compared with controls (5% vs. 12%; p = 0.04); T2DM was associated with low TBS (OR: 2.47, C.I. 95%: 1.19-5.16, p = 0.016) in a regression model adjusted for age, menopausal status and BMI. In women with T2DM, TBS directly correlated with plasma high-density lipoprotein cholesterol (HDL-c) (p = 0.029) and vitamin D (p = 0.017) levels. An inverse association was observed with menopausal status (p < 0.001), metabolic syndrome (p = 0.014), BMI (p = 0.005), and waist circumference (p < 0.001). In the multivariate regression analysis, lower HDL-c represented the main predictor of altered bone quality in T2DM, regardless of age, menopausal status, BMI, waist circumference, statin treatment, physical activity, and vitamin D (p = 0.029; R2 = 0.47), which likely underlies common pathways between metabolic disease and bone health in diabetes.

CAPTURE: A cross-sectional study on the prevalence of cardiovascular disease in adults with type 2 diabetes in Italy.

BACKGROUND AND AIMS: The prevalence of type 2 diabetes (T2D) in Italy is increasing and cardiovascular disease (CVD) represents the leading cause of death in this population. CAPTURE was a multinational, multicentre, non-interventional, cross-sectional study assessing the prevalence of CVD, atherosclerotic CVD (AsCVD) and CVD subtypes among patients with T2D, across 13 countries. Here we report the results from Italy. METHODS AND RESULTS: Overall, 816 patients with T2D (median age, 69 years [interquartile range: 62-75]; median duration of diabetes, 11.2 years [interquartile range: 5.7-18.7]) were recruited during routine clinical visits at secondary care centres in Italy between December 2018-September 2019. The prevalence of CVD was estimated at 38.8%, largely accounted for by AsCVD (33.1%). The most prevalent CVD subtype was coronary heart disease (20.8%), followed by carotid artery disease (13.2%). Most patients (85.9%) were prescribed oral glucose-lowering agents (GLAs), particularly biguanide (76.7%). Insulin use was higher in patients with CVD (41.3%) than in patients without CVD (32.9%). Sodium-glucose co-transporter-2 inhibitors (SGLT2is) and glucagon-like peptide-1 receptor agonists (GLP-1 RAs) were prescribed to 20.2% vs 14.6%, and 14.5% vs 16.6% of patients with CVD compared to those without CVD, respectively. CONCLUSION: The results show that, in Italy, more than one in three patients with T2D attending secondary care centres have CVD, 85% of whom have AsCVD, yet only a minority are treated with SGLT2is and GLP-1 RAs, in discordance with the recommendations of current national and international guidelines.

Role of Biliverdin Reductase A in the Regulation of Insulin Signaling in Metabolic and Neurodegenerative Diseases: An Update.

Insulin signaling is a conserved pathway that orchestrates glucose and lipid metabolism, energy balance, and inflammation, and its dysregulation compromises the homeostasis of multiple systems. Insulin resistance is a shared hallmark of several metabolic diseases, including obesity, metabolic syndrome, and type 2 diabetes, and has been associated with cognitive decline during aging and dementia. Numerous mechanisms promoting the development of peripheral and central insulin resistance have been described, although most of them were not completely clarified. In the last decades, several studies have highlighted that biliverdin reductase-A (BVR-A), over its canonical role in the degradation of heme, acts as a regulator of insulin signaling. Evidence from human and animal studies show that BVR-A alterations are associated with the aberrant activation of insulin signaling, metabolic syndrome, liver steatosis, and visceral adipose tissue inflammation in obese and diabetic individuals. In addition, recent findings demonstrated that reduced BVR-A levels or impaired BVR-A activation contribute to the development of brain insulin resistance and metabolic alterations in Alzheimer's disease. In this narrative review, we will provide an overview on the literature by focusing on the role of BVR-A in the regulation of insulin signaling and how BVR-A alterations impact on cell dysfunctions in both metabolic and neurodegenerative disorders.

New Insights in the Control of Fat Homeostasis: The Role of Neurotensin.

Neurotensin (NT) is a small peptide with pleiotropic functions, exerting its primary actions by controlling food intake and energy balance. The first evidence of an involvement of NT in metabolism came from studies on the central nervous system and brain circuits, where NT acts as a neurotransmitter, producing different effects in relation to the specific region involved. Moreover, newer interesting chapters on peripheral NT and metabolism have emerged since the first studies on the NT-mediated regulation of gut lipid absorption and fat homeostasis. Intriguingly, NT enhances fat absorption from the gut lumen in the presence of food with a high fat content, and this action may explain the strong association between high circulating levels of pro-NT, the NT stable precursor, and the increased incidence of metabolic disorders, cardiovascular diseases, and cancer observed in large population studies. This review aims to provide a synthetic overview of the main regulatory effects of NT on several biological pathways, particularly those involving energy balance, and will focus on new evidence on the role of NT in controlling fat homeostasis, thus influencing the risk of unfavorable cardio-metabolic outcomes and overall mortality in humans.

Deep Resequencing of 9 Candidate Genes Identifies a Role for ARAP1 and IGF2BP2 in Modulating Insulin Secretion Adjusted for Insulin Resistance in Obese Southern Europeans.

Type 2 diabetes is characterized by impairment in insulin secretion, with an established genetic contribution. We aimed to evaluate common and low-frequency (1-5%) variants in nine genes strongly associated with insulin secretion by targeted sequencing in subjects selected from the extremes of insulin release measured by the disposition index. Collapsing data by gene and/or function, the association between disposition index and nonsense variants were significant, also after adjustment for confounding factors (OR = 0.25, 95% CI = 0.11-0.59, p = 0.001). Evaluating variants individually, three novel variants in ARAP1, IGF2BP2 and GCK, out of eight reaching significance singularly, remained associated after adjustment. Constructing a genetic risk model combining the effects of the three variants, only carriers of the ARAP1 and IGF2BP2 variants were significantly associated with a reduced probability to be in the lower, worst, extreme of insulin secretion (OR = 0.223, 95% CI = 0.105-0.473, p < 0.001). Observing a high number of normal glucose tolerance between carriers, a regression posthoc analysis was performed. Carriers of genetic risk model variants had higher probability to be normoglycemic, also after adjustment (OR = 2.411, 95% CI = 1.136-5.116, p = 0.022). Thus, in our southern European cohort, nonsense variants in all nine candidate genes showed association with better insulin secretion adjusted for insulin resistance, and we established the role of ARAP1 and IGF2BP2 in modulating insulin secretion.

Adipose tissue remodelling in obese subjects is a determinant of presence and severity of fatty liver disease.

AIMS: Experimental data suggest that visceral adipose tissue (VAT) dysfunction contributes to non-alcoholic fatty liver disease (NAFLD) development in obesity, however, data on humans are limited. Aims of this study were to investigate the relationship between NAFLD and VAT morphofunctional impairment and to determine whether the extent of VAT remodelling is associated with liver damage and metabolic alterations in obesity. METHODS: We analysed data from 40 obese individuals candidate to bariatric surgery in whom paired intraoperative liver and omental biopsies were performed for diagnosing NAFLD and VAT inflammation by immunohistochemistry and mRNA expression studies. RESULTS: Within our study population, NAFLD was significantly associated with greater VAT CD68+ macrophages infiltration (P = .04), fibrosis (P = .04) and impaired microvascular density (P = .03) as well as increased expression of markers of local hypoxia, apoptosis and inflammation (UNC5B, CASP7, HIF1-α, IL-8, MIP2, WISP-1, all P < .01). The degree of VAT inflammation correlated with the severity of hepatic injury (steatosis, inflammation, fibrosis; all P < .01) and impaired gluco-metabolic profile. CONCLUSIONS: In obese patients, NAFLD is associated in a dose-dependent manner with signs of VAT remodelling, which reflect more severe clinical metabolic impairment. Our study depicts morphological alterations and novel mediators of VAT dysfunction, adding knowledge for future therapeutic approaches to NAFLD and its metabolic complications.

Association of Apelin Levels in Overweight-obese Children with Pubertal Development, but Not with Insulin Sensitivity: 6.5 Years Follow up Evaluation.

BACKGROUND: Obesity in youth is associated with increased risk of metabolic disorders. Adipose tissue hormones are involved in body-weight regulation. Among these, apelin is recognized as an insulin-sensitizer adipokine. Data on apelin levels in obese children and its relation to insulin-sensitivity are limited. OBJECTIVE: We aimed to evaluate apelin levels in relation to obesity and insulin sensitivity in a large cohort of overweight/obese children and adolescents. Furthermore, these youths were reevaluated after a median 6.5 years of follow-up, thus allowing assessing changes in apelin levels in relation to increasing age and weight changes. METHODS: Clinical data in 909 children and adolescents were collected between 2007 and 2010. Two hundred and one were reexamined at a median 6.5 years of follow-up. All subjects at baseline and at follow-up underwent an OGTT. Apelin levels were measured on sera by ELISA method. RESULTS: At baseline, lower apelin levels were associated with increasing age and puberty (Tanner ≥II 0.67 ± 0.96 ng/mL vs. Tanner I 0.89 ± 1.13 ng/mL, p < .002), but not with body-weight. At follow-up, apelin levels in the 201 subjects reexamined were significantly lower than at baseline (0.45 ± 0.77 ng/mL at follow-up, 0.68 ± 0.95 ng/mL baseline, p < .001), confirming the effects of age and puberty. Body-weight did not affect apelin levels. Multiple regression analysis confirmed that sex and puberty were associated with lower apelin levels, independently from age and insulin-sensitivity. CONCLUSIONS: Apelin levels decrease significantly with pubertal development, whilst body-weight in children and adolescents did not determine changes in apelin. Reduced levels of apelin in children and adolescents may therefore represent a necessary response to maintain the "physiological" insulin resistance of puberty. Abbreviations: ALT: Alanine aminotransferase; AST: Aspartate aminotransferase; G: glucose; BMI: Body mass index; DBP: Diastolic blood pressure; ELISA: enzyme-linked immunosorbent assay; HDL-C: High-density lipoprotein-cholesterol; HOMA-B: Homeostatic model assessment for beta-cell function; HOMA-IR: Homeostatic model assessment of insulin-resistance; INS: Insulin; ISI: insulin-sensitivity index; LDL-C: Low-density lipoprotein cholesterol; NW: normal weight; OB: obese; OGTT: oral glucose tolerance test; OW: overweight; SBP: Systolic blood pressure; TC: Total cholesterol; TGs: Triglycerides.

Angiopoietin-Like Protein 4 Overexpression in Visceral Adipose Tissue from Obese Subjects with Impaired Glucose Metabolism and Relationship with Lipoprotein Lipase.

Angiopoietin-like protein 4 (ANGPTL4) regulates lipid partitioning by inhibiting circulating and tissue lipoprotein lipase (LPL); ANGPTL4 loss-of-function variants improve insulin sensitivity and reduce type 2 diabetes (T2D) risk with mechanisms partially unknown. This study was designed to explore metabolic implications of differential ANGPTL4 and LPL expression in human adipose tissue (AT). We recruited eighty-eight obese individuals, with and without abnormal glucose metabolism (AGM), undergoing bariatric surgery; visceral AT (VAT) fragments were obtained intra-operatively and analyzed by immunohistochemistry and mRNA by rt-PCR. Data on hepatic ANGPTL4 mRNA were available for 40 participants. VAT ANGPTL4 expression was higher in AGM individuals than in those with normal glucose tolerance (NGT) and associated with VAT inflammation, insulin resistance, and presence of adipocyte size heterogeneity. Increased ANGPTL4 was associated with AGM with OR = 5.1 (95% C.I.: 1.2-23; p = 0.02) and AUROC = 0.76 (95% C.I.: 1.2-23; p < 0.001). High LPL was associated with the detection of homogeneous adipocyte size, reduced microvessel density, and higher HIF-1α levels and inversely correlated to blood transaminases. In conclusion, in obese individuals, VAT ANGPTL4 levels are increased in the presence of local inflammation and AGM. Conversely, higher LPL expression describes a condition of increased lipid storage in adipocytes, which may serve as a protective mechanism against ectopic fat accumulation and related metabolic disease in obesity.

Reduced Biliverdin Reductase-A Expression in Visceral Adipose Tissue is Associated with Adipocyte Dysfunction and NAFLD in Human Obesity.

Biliverdin reductase A (BVR-A) is an enzyme involved in the regulation of insulin signalling. Knockout (KO) mice for hepatic BVR-A, on a high-fat diet, develop more severe glucose impairment and hepato-steatosis than the wild type, whereas loss of adipocyte BVR-A is associated with increased visceral adipose tissue (VAT) inflammation and adipocyte size. However, BVR-A expression in human VAT has not been investigated. We evaluated BVR-A mRNA expression levels by real-time PCR in the intra-operative omental biopsy of 38 obese subjects and investigated the association with metabolic impairment, VAT dysfunction, and biopsy-proven non-alcoholic fatty liver disease (NAFLD). Individuals with lower VAT BVR-A mRNA levels had significantly greater VAT IL-8 and Caspase 3 expression than those with higher BVR-A. Lower VAT BVR-A mRNA levels were associated with an increased adipocytes' size. An association between lower VAT BVR-A expression and higher plasma gamma-glutamyl transpeptidase was also observed. Reduced VAT BVR-A was associated with NAFLD with an odds ratio of 1.38 (95% confidence interval: 1.02-1.9; χ2 test) and with AUROC = 0.89 (p = 0.002, 95% CI = 0.76-1.0). In conclusion, reduced BVR-A expression in omental adipose tissue is associated with VAT dysfunction and NAFLD, suggesting a possible involvement of BVR-A in the regulation of VAT homeostasis in presence of obesity.

Elevated plasma copeptin levels identify the presence and severity of non-alcoholic fatty liver disease in obesity.

INTRODUCTION: Copeptin is the stable surrogate marker of vasopressin (VP), which is released in response to elevated plasma osmolality or low blood pressure. Elevated plasma copeptin levels are associated with higher risk of insulin resistance-related disorders, such as type 2 diabetes (T2DM), metabolic syndrome (MS), and cardiovascular disease, and experimental reduction of circulating VP levels is shown to significantly decrease hepatic fat content in obese rats, independently from body adiposity. However, the association between copeptin and non-alcoholic fatty liver disease and steatohepatitis (NAFLD/NASH) in humans has not been explored yet. The aim of this study was to explore the relationship between plasma copeptin and the presence/severity of NAFLD/NASH. METHODS: For this study, we recruited 60 obese patients candidate to bariatric surgery for clinical purposes in which intraoperative liver biopsies were performed for diagnosing NAFLD/NASH. Circulating copeptin levels were also assessed in 60 age- and sex-comparable non-obese individuals without NAFLD at liver ultrasonography. Plasma copeptin was measured by sandwich immunoluminometric assay (Thermo Fisher Scientific). RESULTS: Obese patients with biopsy-proven NAFLD (53%) had significantly higher copeptin levels than both obese individuals without NAFLD and non-obese subjects (ob/NAFLD+ 9.5 ± 4.9; ob/NAFLD- 6.4 ± 2.6; and non-ob/NAFLD- 7.4 ± 5.1 pmol/L; p = 0.004 and p = 0.01 respectively). Plasma copeptin concentration positively correlated with hepatic macro- and micro-vesicular steatosis (r = 0.36, p = 0.026; r = 0.31, p = 0.05), lobular inflammation (r = 0.37, p = 0.024) and significantly increased throughout degrees of NASH severity, as expressed as absence, borderline, and overt NASH at the liver biopsy (r = 0.35, p = 0.01). Greater circulating copeptin predicted the presence of NASH with OR = 1.73 (95% CI = 1.02-2.93) after multivariate adjustment for age, sex, renal function and presence of T2DM and MS components. CONCLUSIONS: Increased plasma copeptin is independently associated with the presence and severity of NAFLD and NASH, pointing to a novel mechanism behind human fatty liver disease potentially modifiable by pharmacological treatment and lifestyle intervention.

Increased circulating granzyme B in type 2 diabetes patients with low-grade systemic inflammation.

In metabolic diseases, like type 2 diabetes (T2D), adipose tissue (AT) is infiltrated by macrophages and other leukocytes - which secrete many bioactive peptides leading to local and systemic low-grade chronic inflammation - and undergoes remodeling and aberrant fibrosis. Granzyme B (GrB) is a serine protease produced by some leukocytes, including cytotoxic lymphocytes and macrophages. It exerts both intracellular apoptotic function and extracellular functions, leading to tissue injury, inflammation and repair. Elevated circulating GrB levels have been found in aging- and inflammation-associated diseases and a role for GrB in the pathogenesis of several chronic inflammatory diseases has been reported. Aims of this study were to investigate circulating GrB levels in T2D patients in relation to their systemic inflammatory profile and to unravel its correlates. For this cross-sectional study, we recruited 51 consecutive T2D patients referring to our diabetes outpatient clinics (Sapienza University, Rome, Italy) for metabolic evaluations, and 29 sex, age and body mass index comparable non-diabetic subjects as control group. Study participants underwent clinical work-up; fasting blood sampling was performed for routine biochemistry and for inflammatory profile (CRP, IL-2, IL-4, IL-6, IL-8, IL-10, TNF-α, IFN-γ, GM-CSF, adiponectin, WISP1); serum GrB was measured by Human Granzyme-B Platinum Elisa kit (Affymetrix EBIO). We found that T2D patients had serum levels of GrB significantly higher than the control group (10.17 ±â€¯12.6 vs 7.2 ±â€¯14.1 pg/ml, p = 0.03). Moreover, in T2D patients increased GrB correlated with unfavorable inflammatory profile, as described by elevated levels of validated adipokines such as IL-6 (p = 0.04), TNF-α (p = 0.019) and WISP1 (p = 0.005). Furthermore, multivariate linear regression analysis showed that increased GrB was associated with T2D diagnosis independently from possible confounders. In conclusion, our results show that increased levels of circulating GrB are associated with T2D diagnosis and correlates with markers of AT-linked systemic inflammation, suggesting a potential role for GrB in the inflammatory and reactive processes occurring in metabolic diseases.

The Arg282Ser missense mutation in APOA5 gene determines a reduction of triglyceride and LDL-cholesterol in children, together with low serum levels of apolipoprotein A-V.

BACKGROUND: Apolipoprotein A-V (ApoA-V) is a recognized regulator of plasma triglycerides (TGs), and previous studies have shown associations between variants in APOA5 (apolipoprotein-A5) gene and high TG levels. Recently, a new association between the Arg282Ser missense mutation (rs778114184 G > T) in APOA5 gene and decreased triglyceride levels has been shown in an adult population from Sardinia. In this study we add further insight into the role of APOA5 by exploring whether this association begins early in life in children, or becomes manifest only in adulthood. We performed the genetic association analysis of APOA5 in a cohort of 925 overweight and obese children and adolescents from Sardinia, Italy, to see if the genetic burden is already at play before modifying risk factors are interacting. RESULTS: We identified 24 heterozygous subjects for the Arg282Ser variant and no homozygous subject. Here we show that the Arg282Ser mutation in APOA5 gene is associated with a significant reduction of TG (-15.5 mg/dl), total (-18.1 mg/dl) and LDL-cholesterol (-14.8 mg/dl) levels in overweight/obese children and adolescents, indicating that indeed this association appears early in life. Also, we observed a significant reduction in serum apoA-V levels in heterozygous children. CONCLUSIONS: Our data clearly show that the Arg282Ser mutation in APOA5 gene determines a reduction of TG, total and LDL-cholesterol and apolipoprotein A-V levels in overweight/obese children and adolescents, demonstrating that this mutation has the power to affect lipid levels already since childhood.

No effects of oral vitamin D supplementation on non-alcoholic fatty liver disease in patients with type 2 diabetes: a randomized, double-blind, placebo-controlled trial.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the most common hepatic disorder worldwide, reaching prevalence up to 90 % in obese patients with type 2 diabetes (T2D), and representing an independent risk factor for cardiovascular mortality. Furthermore, the coexistence of T2D and NAFLD leads to higher incidence of diabetes' complications and additive detrimental liver outcomes. The existence of a close association between NAFLD and hypovitaminosis D, along with the anti-inflammatory and insulin-sensitizing properties of vitamin D, have been largely described, but vitamin D effects on hepatic fat content have never been tested in a randomized controlled trial. We assessed the efficacy and safety of 24-week oral high-dose vitamin D supplementation in T2D patients with NAFLD. METHODS: This randomized, double-blind, placebo-controlled trial was carried out at the Diabetes Centre of Sapienza University, Rome, Italy, to assess oral treatment with cholecalciferol (2000 IU/day) or placebo in T2D patients with NAFLD. The primary endpoint was reduction of hepatic fat fraction (HFF) measured by magnetic resonance; as hepatic outcomes, we also investigated changes in serum transaminases, CK18-M30, N-terminal Procollagen III Propeptide (P3NP) levels, and Fatty Liver Index (FLI). Secondary endpoints were improvement in metabolic (fasting glycaemia, HbA1c, lipids, HOMA-IR, HOMA-ß, ADIPO-IR, body fat distribution) and cardiovascular (ankle-brachial index, intima-media thickness, flow-mediated dilatation) parameters from baseline to end of treatment. RESULTS: Sixty-five patients were randomized, 26 (cholecalciferol) and 29 (placebo) subjects completed the study. 25(OH) vitamin D significantly increased in the active treated group (48.15 ± 23.7 to 89.80 ± 23.6 nmol/L, P < 0.001); however, no group differences were found in HFF, transaminases, CK18-M30, P3NP levels or FLI after 24 weeks. Vitamin D neither changed the metabolic profile nor the cardiovascular parameters. CONCLUSIONS: Oral high-dose vitamin D supplementation over 24 weeks did not improve hepatic steatosis or metabolic/cardiovascular parameters in T2D patients with NAFLD. Studies with a longer intervention period are warranted for exploring the effect of long time exposure to vitamin D. TRIAL REGISTRATION: This trial was approved on July 2011 by the Ethics Committee of Policlinico Umberto I, Sapienza University of Rome, Italy, and registered at www.clinicaltrialsregister.eu number 2011-003010-17.

Phenotypical heterogeneity linked to adipose tissue dysfunction in patients with Type 2 diabetes.

Adipose tissue (AT) inflammation leads to increased free fatty acid (FFA) efflux and ectopic fat deposition, but whether AT dysfunction drives selective fat accumulation in specific sites remains unknown. The aim of the present study was to investigate the correlation between AT dysfunction, hepatic/pancreatic fat fraction (HFF, PFF) and the associated metabolic phenotype in patients with Type 2 diabetes (T2D). Sixty-five consecutive T2D patients were recruited at the Diabetes Centre of Sapienza University, Rome, Italy. The study population underwent clinical examination and blood sampling for routine biochemistry and calculation of insulin secretion [homoeostasis model assessment of insulin secretion (HOMA-ß%)] and insulin-resistance [homoeostasis model assessment of insulin resistance (HOMA-IR) and adipose tissue insulin resistance (ADIPO-IR)] indexes. Subcutaneous (SAT) and visceral (VAT) AT area, HFF and PFF were determined by magnetic resonance. Some 55.4% of T2D patients had non-alcoholic fatty liver disease (NAFLD); they were significantly younger and more insulin-resistant than non-NAFLD subjects. ADIPO-IR was the main determinant of HFF independently of age, sex, HOMA-IR, VAT, SAT and predicted severe NAFLD with the area under the receiver operating characteristic curve (AUROC)=0.796 (95% confidence interval: 0.65-0.94, P=0.001). PFF was independently associated with increased total adiposity but did not correlate with AT dysfunction, insulin resistance and secretion or NAFLD. The ADIPO-IR index was capable of predicting NAFLD independently of all confounders, whereas it did not seem to be related to intrapancreatic fat deposition; unlike HFF, higher PFF was not associated with relevant alterations in the metabolic profile. In conclusion, the presence and severity of AT dysfunction may drive ectopic fat accumulation towards specific targets, such as VAT and liver, therefore evaluation of AT dysfunction may contribute to the identification of different risk profiles among T2D patients.

Hypovitaminosis D in recent onset rheumatoid arthritis is predictive of reduced response to treatment and increased disease activity: a 12 month follow-up study.

BACKGROUND: Vitamin D displays immunomodulatory activities and has been proposed as a potential player in the pathogenesis of rheumatoid arthritis (RA). A negative association between serum 25(OH) vitamin D levels and RA activity was demonstrated but longitudinal studies investigating the role of vitamin D levels in predicting RA activity and response to treatment are lacking. Therefore, this study was designed to test the hypothesis of an association between serum 25(OH) vitamin D levels at RA diagnosis and disease activity evaluated by clinimetric, laboratory and ultrasound (US) parameters and to detect the prevalence of remission and response to treatment after 12 months follow-up. METHODS: This is a longitudinal, retrospective study on data obtained from thirty-seven patients with early RA treatment-naïve. Serum inflammatory markers, auto-antibodies and 25(OH) vitamin D levels were obtained at baseline. Hypovitaminosis D was diagnosed for 25(OH) vitamin D levels < 20 ng/ml. Tender joint count (TJCs), swollen joint count (SJCs), Visual Analog Scales (VAS), Disease Activity Score (DAS) 28 score were assessed at baseline and 12 months after diagnosis. Joints synovitis and power-Doppler were evaluated at baseline and 12 months later. RESULTS: At baseline mean 25(OH) vitamin D levels were 24.4 ± 11.9 ng/ml; 35% of study subjects had hypovitaminosis D which strongly associated with higher RA activity and lower prevalence of remission and response to treatment (all p-values < 0.001). The percentage of patients not presenting a reduction of the US synovitis score after 12 months from diagnosis was significantly higher among patients with hypovitaminosis D than in those with normal serum 25(OH) vitamin D at baseline. CONCLUSIONS: In patients with early RA and basal hypovitaminosis D after 12 months follow-up reduction of disease activity and percentage of remission and response to treatment were significantly lower than those observed in patients with normal vitamin D levels. These results provide further support to the immunomodulatory action of vitamin D in RA and suggest a role of basal vitamin D status in the prediction of disease evolution. Vitamin D measurement and possibly vitamin D supplementation should be considered an additional option in the management of early RA patients.