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OBJECTIVE Type 2 diabetes is characterized by increased death rate. In order to tackle this dramatic event, it becomes essential to discover novel biomarkers capable of identifying high-risk patients to be exposed to more aggressive preventive and treatment strategies. hs-CRP and serum amyloid P component (SAP) are two acute-phase inflammation proteins, which interact physically and share structural and functional features. We investigated their combined role in associating with and improving prediction of mortality in type 2 diabetes. RESEARCH DESIGN AND METHODS Four cohorts comprising 2,499 patients with diabetes (643 all-cause deaths) were analyzed. The improvement of mortality prediction was addressed using two well-established prediction models, namely, EstimatioN oF mORtality risk in type 2 diabetiC patiEnts (ENFORCE) and Risk Equations for Complications of Type 2 Diabetes (RECODe). RESULTS Both hs-CRP and SAP were independently associated with all-cause mortality (hazard ratios [HRs] [95% CIs]: 1.46 [1.34–1.58] [P < 0.001] and 0.82 [0.76–0.89] [P < 0.001], respectively). Patients with SAP ≤33 mg/L were at increased risk of death versus those with SAP >33 mg/L only if hs-CRP was relatively high (>2 mg/L) (HR 1.96 [95% CI 1.52–2.54] [P < 0.001] and 1.20 [0.91–1.57] [P = 0.20] in hs-CRP >2 and ≤2 mg/L subgroups, respectively; hs-CRP-by-SAP strata interaction P < 0.001). The addition of hs-CRP and SAP significantly (all P < 0.05) improved several discrimination and reclassification measures of both ENFORCE and RECODe all-cause mortality prediction models. CONCLUSIONS In type 2 diabetes, hs-CRP and SAP show opposite and synergic associations with all-cause mortality. The use of both markers, possibly in combination with others yet to be unraveled, might improve the ability to predict the risk of death in the real-life setting.

Death rate is increased in type 2 diabetes. Unraveling biomarkers of novel pathogenic pathways capable to identify high-risk patients is instrumental to tackle this burden. We investigated the association between serum metabolites and all-cause mortality in type 2 diabetes and then whether the associated metabolites mediate the effect of inflammation on mortality risk and improve ENFORCE (EstimatioN oF mORtality risk in type2 diabetic patiEnts) and RECODe (Risk Equation for Complications Of type 2 Diabetes), two well-established all-cause mortality prediction models in diabetes. Two cohorts comprising 856 individuals (279 all-cause deaths) were analyzed. Serum metabolites (n = 188) and pro- and anti-inflammatory cytokines (n = 7) were measured. In the pooled analysis, hexanoylcarnitine, kynurenine, and tryptophan were significantly and independently associated with mortality (hazard ratio [HR] 1.60 [95% CI 1.43–1.80]; 1.53 [1.37–1.71]; and 0.71 [0.62–0.80] per 1 SD). The kynurenine-to-tryptophan ratio (KTR), a proxy of indoleamine-2,3-dioxygenase, which degrades tryptophan to kynurenine and contributes to a proinflammatory status, mediated 42% of the significant association between the antiatherogenic interleukin (IL) 13 and mortality. Adding the three metabolites improved discrimination and reclassification (all P < 0.01) of both mortality prediction models. In type 2 diabetes, hexanoylcarnitine, tryptophan, and kynurenine are associated to and improve the prediction of all-cause mortality. Further studies are needed to investigate whether interventions aimed at reducing KTR also reduce the risk of death, especially in patients with low IL-13.

Gluten Friendly™ (GF) is a new gluten achieved through a physicochemical process applied to wheat kernels. The goal of this research was to assess the in vivo effects of Gluten Friendly™ bread on celiac gut mucosa and microbiota. In a double-blind placebo-controlled intervention study, 48 celiac disease (CD) patients were randomized into 3 groups to eat 100 g of bread daily, containing different doses (0; 3 g; 6 g) of GF for 12 weeks. The small-bowel morphology (VH/CrD), intraepithelial densities of CD3+, celiac serology, MUC2, CB1, gut permeability, proinflammatory cytokines, gluten in stools, symptoms, and gut microbial composition were assessed. All 48 CD subjects experienced no symptoms. K-means analysis evidenced celiac subjects clustering around unknown parameters independent of GF dosage: K1 35%; K2 30%; K3 35%. VH/CrD significantly decreased in K1 and K2. VH/CrD did not correlate with IEL increase in K2. 33-mer was not detected in 47% and 73% of patients in both K1 and K2, respectively. VH/CrD and IEL did not change significantly and strongly correlated with the absence of 33-mer in K3. Inflammation and VH/CrD decrease are strongly related with the presence of proinflammatory species at the baseline. A boost in probiotic, butyrate-producing genera, is strongly related with GF tolerance at the end of the trial. Our research suggests that a healthy and proinflammatory ecology could play a crucial role in the digestion and tolerance of the new gluten molecule in celiac subjects. However, GF can be completely digested by gut microbiota of CD subjects and shapes it toward gut homeostasis by boosting healthy butyrate-producing populations. The clinical trial registry number is NCT03137862 (https://clinicaltrials.gov). publishedVersion

Monogenic diabetes is a genetic disorder caused by one or more variations in a single gene. It encompasses a broad spectrum of heterogeneous conditions, including neonatal diabetes, maturity onset diabetes of the young (MODY) and syndromic diabetes, affecting 1–5% of patients with diabetes. Some of these variants are harbored by genes whose altered function can be tackled by specific actions (“actionable genes”). In suspected patients, molecular diagnosis allows the implementation of effective approaches of precision medicine so as to allow individual interventions aimed to prevent, mitigate or delay clinical outcomes. This review will almost exclusively concentrate on the clinical strategy that can be specifically pursued in carriers of mutations in “actionable genes”, including ABCC8, KCNJ11, GCK, HNF1A, HNF4A, HNF1B, PPARG, GATA4 and GATA6. For each of them we will provide a short background on what is known about gene function and dysfunction. Then, we will discuss how the identification of their mutations in individuals with this form of diabetes, can be used in daily clinical practice to implement specific monitoring and treatments. We hope this article will help clinical diabetologists carefully consider who of their patients deserves timely genetic testing for monogenic diabetes.

We describe early-onset diabetes in a 6-month-old patient carrying an LRBA gene mutation. Mutations in this gene cause primary immunodeficiency with autoimmune disorders in infancy. At admission, he was in diabetic ketoacidosis, and treatment with fluid infusion rehydration and then i.v. insulin was required. He was discharged with a hybrid closed-loop system for insulin infusion and prevention of hypoglycemia (Minimed Medtronic 670G). He underwent a next-generation sequencing analysis for monogenic diabetes genes, which showed that he was compound heterozygous for two mutations in the LRBA gene. In the following months, he developed arthritis of hands and feet, chronic diarrhea, and growth failure. He underwent bone marrow transplantation with remission of diarrhea and arthritis, but not of diabetes and growth failure. The blood glucose control has always been at target (last HbA1c 6%) without any severe hypoglycemia. LRBA gene mutations are a very rare cause of autoimmune diabetes. This report describes the clinical course in a very young patient. The hybrid closed-loop system was safe and efficient in the management of blood glucose. This report describes the clinical course of diabetes in a patient with a novel LRBA gene mutation.

Context Type 2 diabetes (T2D) shows a high mortality rate, partly mediated by atherosclerotic plaque instability. Discovering novel biomarkers may help identify high-risk patients who would benefit from more aggressive and specific managements. We recently described a serum resistin and multicytokine inflammatory pathway (REMAP), including resistin, interleukin (IL)-1β, IL-6, IL-8, and TNF-α, that is associated with cardiovascular disease. Objective We investigated whether REMAP is associated with and improves the prediction of mortality in T2D. Methods A REMAP score was investigated in 3 cohorts comprising 1528 patients with T2D (409 incident deaths) and in 59 patients who underwent carotid endarterectomy (CEA; 24 deaths). Plaques were classified as unstable/stable according to the modified American Heart Association atherosclerosis classification. Results REMAP was associated with all-cause mortality in each cohort and in all 1528 individuals (fully adjusted hazard ratio [HR] for 1 SD increase = 1.34, P Conclusion REMAP is independently associated with and improves predict all-cause mortality in T2D; it can therefore be used to identify high-risk individuals to be targeted with more aggressive management. Whether REMAP can also identify patients who are more responsive to IL-6 and IL-1β monoclonal antibodies that reduce cardiovascular burden and total mortality is an intriguing possibility to be tested.

Context Some studies have surprisingly indicated that serum adiponectin level is positively related to mortality rate, thus casting doubts on its role as a therapeutic target for cardiovascular disease. Objective To summarize evidence about direction, strength, and modulators of this controversial association. Methods MEDLINE, Web of Science, CINHAL, Cochrane Library, and Scopus databases were searched from their inception dates through June 2018 for English-language prospective studies reporting the association between adiponectin and all-cause or cardiovascular mortality. Two investigators independently extracted data and assessed study quality using standard criteria following the Preferred Reporting Items for Systematic Reviews and Meta-analyses and The Newcastle-Ottawa Scale. Pooled hazard ratios (HRs) and 95% CIs were derived using fixed- or random-effects models when appropriate, and results were expressed to a 1-SD increment of adiponectin. Results We identified 55 studies (n = 61,676 subjects) with all-cause mortality data and 28 (n = 43,979 subjects) studies with cardiovascular mortality data. Pooled HRs were 1.24 (1.17-1.31) and 1.28 (1.19-1.37) for all-cause and cardiovascular mortality, respectively. Similar results were obtained for high-molecular-weight adiponectin. When meta-analyses were restricted to studies reporting data on natriuretic peptides, reductions of 43% and 28% on a log scale of these respective associations were observed after adjusting for natriuretic peptides. Conclusions Our results point strongly to a paradoxical association between high adiponectin levels and increased mortality rate, which is partly modulated by natriuretic peptides.

Basic science studies have shown beneficial effects of adiponectin on glucose homeostasis, chronic low-grade inflammation, apoptosis, oxidative stress, and atherosclerotic processes, so this molecule usually has been considered a salutary adipokine. It was therefore quite unexpected that large prospective human studies suggested that adiponectin is simply a marker of glucose homeostasis, with no direct favorable effect on the risk of type 2 diabetes and cardiovascular disease. But even more unforeseen were data addressing the role of adiponectin on the risk of death. In fact, a positive, rather than the expected negative, relationship was reported between adiponectin and mortality rate across many clinical conditions, comprising diabetes. The biology underlying this paradox is unknown. Several explanations have been proposed, including adiponectin resistance and the confounding role of natriuretic peptides. In addition, preliminary genetic evidence speaks in favor of a direct role of adiponectin in increasing the risk of death. However, none of these hypotheses are based on robust data, so further efforts are needed to unravel the elusive role of adiponectin on cardiometabolic health and, most important, its paradoxical association with mortality rate.

CRP and SAP are the two short, strongly homologous pentraxins produced in response to inflammation. Though their common contribution to innate immunity, they seem to differently affect atherosclerosis and related clinical outcomes. In the specific context of mortality rate i) CRP is a recognized risk biomarker; ii) data on SAP are sparse and conflicting; iii) no data are available on their possibly combined effect. Accordingly, the combined effect of CRP and SAP on mortality risk was investigated in the high-risk subset of patients with type 2 diabetes (T2D). Four cohorts of patients with T2D [i.e., Gargano Heart Study (GHS; n=358; follow-up (f-u)=5±3 years; 81 events); Gargano Mortality Study (n=650; f-u=11±4 years; 190 events); Foggia Mortality Study (n=530; f-u=7±3 years; 146 events) and Pisa Mortality Study (n=986; f-u=13±3 years; 230 events)] were analyzed by Cox proportional hazard models. In the pooled sample, with a total of 2,524 individuals experiencing 647 events, hs-CRP was positively [HR=1.53 (95% CI 1.41-1.66)] whereas SAP was negatively [HR=0.80 (95% CI 0.74-0.86)] associated with all-cause mortality. Similar results were observed on cardiovascular death in GHS: HR (95% CI) being 1.90 (1.48-2.44) and 0.78 (0.61-0.98) for hs-CRP and SAP, respectively. The whole sample was then stratified according to relatively low and high hs-CRP and SAP (< or > the median value), so to obtain four groups: low/high (1), low/low (2), high/high (3), and high/low (4) hs-CRP/SAP levels. As compared to group 1, group 2, 3 and 4 had HRs (95% CIs) of 1.25 (0.96-1.64), 1.80 (1.39-2.33) and 2.40 (1.81-3.17) for all-cause mortality (p for trend=1.1x10-11 or, in a model comprising study sample, age, sex, smoking habit, BMI, HbA1c, diabetes duration and all ongoing treatments, p=4.1x10-8). In conclusion, in patients with T2D, hs-CRP and SAP show a combined effect on all-cause death. Whether their simultaneous use may prove to be useful in predicting mortality in T2D needs further investigation. Disclosure M. Scarale: None. M. Copetti: None. M. Garofolo: None. L. Salvemini: None. S. De Csomo: None. O. Lamacchia: None. G. Penno: None. V. Trischitta: None. C. Menzaghi: None. Funding Italian Ministry of Health (RF-2013-02356459)

While elevated serum adiponectin and resistin levels have been singly associated with all-cause mortality in patients with type 2 diabetes (T2D), their combined effect has never been studied. We investigated such joint effect in patients with T2D and its possible modulation by several demographic and clinical conditions, known to affect per se mortality rate.Patients with T2D from the Gargano Mortality Study (GMS; N = 895, follow-up = 10.5 ± 3.7 years; 290 events) and the Foggia Mortality Study (FMS; N = 519, follow-up = 7.1 ± 2.5 years; 140 events) were examined.As singly considered, adiponectin and resistin were independently associated with mortality rate in GMS and FMS (p 0.0001 for both). The two studies were then pooled, for investigating the nature of the joint effect of the two adipokines. In such sample, both adipokines were associated with death, independent of each other and of several additional covariates (p = 0.01-4.58 × 10(-12)). Of note, no adiponectin-by-resistin interaction was observed (p = 0.40), thus pointing to an additive effect of the two adipokines. As compared to individuals with low levels of both adiponectin and resistin (i.e. below median values), those with high levels of both adipokines had an HR (95%CI) for death of 3.02 (2.26-4.03). Such increased risk was more pronounced in individuals with relatively low abdominal adiposity (p for HR heterogeneity below or above the median value of waist circumference = 0.03).Adiponectin and resistin show an additive independent effect on all-cause mortality in patients with T2D. Such effect is modified by abdominal adiposity.

ContextWe previously developed and validated an inexpensive and parsimonious prediction model of 2-year all-cause mortality in real-life patients with type 2 diabetes.ObjectiveThis model, now named ENFORCE (EstimatioN oF mORtality risk in type 2 diabetiC patiEnts), was investigated in terms of (i) prediction performance at 6 years, a more clinically useful time-horizon; (ii) further validation in an independent sample; and (iii) performance comparison in a real-life vs a clinical trial setting.DesignObservational prospective randomized clinical trial.SettingWhite patients with type 2 diabetes.PatientsGargano Mortality Study (GMS; n = 1019), Foggia Mortality Study (FMS; n = 1045), and Pisa Mortality Study (PMS; n = 972) as real-life samples and the standard glycemic arm of the ACCORD (Action to Control Cardiovascular Risk in Diabetes) clinical trial (n = 3150).Main Outcome MeasureThe endpoint was all-cause mortality. Prediction accuracy and calibration were estimated to assess the model's performances.ResultsENFORCE yielded 6-year mortality C-statistics of 0.79, 0.78, and 0.75 in GMS, FMS, and PMS, respectively (P heterogeneity = 0.71). Pooling the three cohorts showed a 6-year mortality C-statistic of 0.80. In the ACCORD trial, ENFORCE achieved a C-statistic of 0.68, a value significantly lower than that obtained in the pooled real-life samples (P < 0.0001). This difference resembles that observed with other models comparing real-life vs clinical trial settings, thus suggesting it is a true, replicable phenomenon.ConclusionsThe time horizon of ENFORCE has been extended to 6 years and validated in three independent samples. ENFORCE is a free and user-friendly risk calculator of all-cause mortality in white patients with type 2 diabetes from a real-life setting.

Surprisingly, several, though not all, studies have shown a positive relationship between serum adiponectin (ADPN) and mortality rate. In order to deeply address direction and strength of this paradoxical association, we carried out a systematic review and meta-analysis (MA) of prospective studies present in MEDLINE, Cochrane Library and Scopus by December, 1st 2017, with ADPN being the exposure and all-cause (AC) and cardiovascular (CV) mortality the outcomes. We performed random effect MA to pool individual hazard ratios (HRs; 95% CIs). To address the role of Natriuretic Peptides (NPs), known to increase both ADPN expression and mortality rate, a MA focused only on studies reporting HRs before and after NPs adjustment was also carried out. We assessed study heterogeneity by Q statistic and then performed meta-regressions considering male percentage, age, BMI, eGFR and clinical setting (general population, type 2 diabetes, CV disease, dialysis) as study level covariates. We identified 56 (n=64,775 subjects) and 30 (n=48,439) studies for AC and CV mortality, respectively. Heterogeneity across studies was observed for both outcomes (Q-test p0.1). For CV mortality (6 studies, n=15,252), HRs were 1.21 (1.10-1.33) and 1.15 (1.06-1.24) without and with NPs adjustment, respectively (p0.8). Male percentage, age, BMI, eGFR and clinical setting did not explain the observed heterogeneity among studies. Our results confirm the existence of a paradoxical association between high ADPN levels and increased mortality rate. Such paradox seems to be only partly explained by NPs levels. Disclosure M. Scarale: None. A. Fontana: None. V. Trischitta: None. M. Copetti: None. C. Menzaghi: None.

In cells and tissues resistin affects IL-1β, IL-6, IL-8, IL-12 and TNF-α expression, thus suggesting the existence of a multi-cytokine “resistin pathway”. We investigated whether such pathway does exist in humans and, if so, if it is associated with cardiovascular risk factors and with major adverse cardiovascular events (MACE). Serum cytokines were measured in 280 healthy subjects from the Gargano Study 2 (GS2) whose BMI, waist circumference, HOMAIR, triglycerides, HDL-cholesterol, systolic and diastolic blood pressure data were available and in 353 patients with type 2 diabetes and coronary artery disease from the Gargano Heart Study (GHS)-prospective design (follow-up 5.4 ± 2.5 years; 71 MACE). In GS2, cytokines mRNA levels in white blood cells were also measured. In GS2, resistin mRNA was correlated with all cytokines expression (all p

Objective : We have previously reported the combined effect of SNPs perturbing insulin signaling ( ENPP1 K121Q, rs1044498; IRS1 G972R, rs1801278; TRIB3 Q84R, rs2295490) on insulin resistance (IR), type 2 diabetes (T2D) and cardiovascular events. We here investigated whether such a combined effect affects also all-cause mortality in a sample of 1851 Whites of European ancestry. Methods : We investigated a first sample of 721 patients, 232 deaths, 3389 person-years (py). Replication was assessed in two samples of patients with T2D: the Gargano Mortality Study (GMS) of 714 patients, 127 deaths, 5426 py and the Joslin Kidney Study (JKS) comprising 416 patients, 214 deaths, 5325 py. Results : In the first sample, individuals carrying 1 or ≥2 risk alleles had 33% ( p = 0.06) and 51% ( p = 0.02) increased risk of mortality, as compared with individuals with no risk alleles. A similar, though not significant, trend was obtained in the two replication samples only for subject carrying ≥ 2 risk alleles. In a pooled analysis, individuals carrying ≥2 risk alleles had higher mortality rate as compared to those carrying 0 risk alleles (HR = 1.34, 95%CI = 1.08–1.67; p = 0.008), and as compared to those carrying only one risk allele (HR = 1.41, 95%CI = 1.13–1.75; p = 0.002). This association was independent from several possible confounders including sex, age, BMI, hypertension and diabetes status. Conclusion : Our data suggest that variants affecting insulin signaling exert a joint effect on all-cause mortality and is consistent with a role of abnormal insulin signaling on mortality risk.

Mortality rate of diabetic patients is twice as much that of non-diabetic individuals. The role of obesity on mortality risk in patients with type 2 diabetes is controversial. Aim of our study was to address the relationship between obesity and all-cause mortality in a real-life set of white patients with type 2 diabetes from central-southern Italy from the Gargano Mortality Study (GMS). In addition, we used genetic data from genome-wide association studies (GWAs)-derived single nucleotide polymorphisms (SNPs) firmly associated with body mass index (BMI), in order to investigate the intrinsic nature of reduced mortality rate we, in fact, observed in obese patients. Study subjects with type 2 diabetes (n = 764) are part of the GMS, which is aimed at unraveling predictors of incident all-cause mortality. Time-to-death analyses were performed by Cox regression. Association between genotype risk score and obesity was tested by logistic regression. Of the 32 SNPs firmly associated with BMI, we investigated those with BMI β value ≥0.10 kg/m(2) and allele frequency ≥10 %. Genotyping was performed by KBioscience (http://www.lgcgenomics.com/). In GMS, obesity predicted a 45 % reduction in all-cause mortality. Individuals with high "obesity genetic load" (i.e., those carrying >9 risk alleles) were 60 % more likely to be obese as compared to individuals with low "obesity genetic load." Most importantly, mortality rate was not different in individuals with high and low "obesity genetic load," thus indicating no role of obesity genes on all-cause mortality and speaking against a cause-effect relationship underlying the association between obesity and reduced mortality rate.

OBJECTIVE To develop and validate a parsimonious model for predicting short-term all-cause mortality in patients with type 2 diabetes mellitus (T2DM). RESEARCH DESIGN AND METHODS Two cohorts of patients with T2DM were investigated. The Gargano Mortality Study (GMS, n = 679 patients) was the training set and the Foggia Mortality Study (FMS, n = 936 patients) represented the validation sample. GMS and FMS cohorts were prospectively followed up for 7.40 ±2.15 and 4.51 ±1.69 years, respectively, and all-cause mortality was registered. A new forward variable selection within a multivariate Cox regression was implemented. Starting from the empty model, each step selected the predictor that, once included into the multivariate Cox model, yielded the maximum continuous net reclassification improvement (cNRI). The selection procedure stopped when no further statistically significant cNRI increase was detected. RESULTS Nine variables (age, BMI, diastolic blood pressure, LDL cholesterol, triglycerides, HDL cholesterol, urine albumin-to-creatinine ratio, and antihypertensive and insulin therapy) were included in the final predictive model with a C statistic of 0.88 (95% CI 0.82–0.94) in the GMS and 0.82 (0.76–0.87) in the FMS. Finally, we used a recursive partition and amalgamation algorithm to identify patients at intermediate and high mortality risk (hazard ratio 7.0 and 24.4, respectively, as compared with those at low risk). A web-based risk calculator was also developed. CONCLUSIONS We developed and validated a parsimonious all-cause mortality equation in T2DM, providing also a user-friendly web-based risk calculator. Our model may help prioritize the use of available resources for targeting aggressive preventive and treatment strategies in a subset of very high-risk individuals.

We read with interest the article on the paradoxical association between high-molecular-weight (HMW) adiponectin and cardiovascular mortality in men with type 2 diabetes mellitus from the HPFS (Health Professional Follow-Up Study).1 These data resemble those we have previously reported2 in men with type 2 diabetes mellitus, comprising a large subset of the same HPSF and additional Italian individuals.2 To address whether such association is sustained by a cause–effect relationship, a genetic risk score (GRS) built on 19 single nucleotide polymorphisms previously associated with adiponectin levels (Mendelian randomization) was used.1 Notably, GRS was not associated with cardiovascular mortality, thus speaking against a causal role of HMW adiponectin on it. This finding is in marked contrast with our recent report, showing a significant association between rs832354 (a single nucleotide polymorphism strongly associated with HMW …

Several lines of evidence suggest a pathogenic role of insulin resistance on kidney dysfunction. Potential mechanisms are mostly due to the effect of single abnormalities related to insulin resistance and clustering into the metabolic syndrome. Hyperinsulinemia, which is inevitably associated to insulin resistance in non diabetic states, also appears to play a role on kidney function by inducing glomerular hyperfiltration and increased vascular permeability. More recently, adipocytokine which are linked to insulin resistance, low grade inflammation, endothelial dysfunction and vascular damage have been proposed as additional molecules able to modulate kidney function. In addition, recent evidences point also to a role of insulin resistance at the level of the podocyte, an important player in early phases of diabetic kidney damage, thus suggesting a new mechanism through which a reduction of insulin action can affect kidney function. In fact, mouse models not expressing the podocyte insulin receptor develop podocytes apoptosis, effacement of its foot processes along with thickening of the glomerular basement membrane, increased glomerulosclerosis and albuminuria. A great number of epidemiological studies have repeatedly reported the association between insulin resistance and kidney dysfunction in both non diabetic and diabetic subjects. Among these, studies addressing the impact of insulin resistance genes on kidney dysfunction have played the important role to help establish a cause-effect relationship between these two traits. Finally, numerous independent intervention studies have shown that a favourable modulation of insulin resistance has a positive effect also on urinary albumin and total protein excretion. In conclusion, several data of different nature consistently support the role of insulin resistance and related abnormalities on kidney dysfunction. Intervention trials designed to investigate whether treating insulin resistance ameliorates also hard renal end-points are both timely and needed.

Resistin is a polypeptide hormone that was reported to be associated with insulin resistance, inflammation and risk of type 2 diabetes and cardiovascular disease. We conducted a genome-wide association (GWA) study on circulating resistin levels in individuals of European ancestry drawn from the two independent studies: the Nurses' Health Study (n = 1590) and the Health, Aging and Body Composition Study (n = 1658). Single-nucleotide polymorphisms (SNPs) identified in the GWA analysis were replicated in an independent cohort of Europeans: the Gargano Family Study (n = 659). We confirmed the association with a previously known locus, the RETN gene (19p13.2), and identified two novel loci near the TYW3/CRYZ gene (1p31) and the NDST4 gene (4q25), associated with resistin levels at a genome-wide significant level, best represented by SNP rs3931020 (P = 6.37 × 10(-12)) and SNP rs13144478 (P = 6.19 × 10(-18)), respectively. Gene expression quantitative trait loci analyses showed a significant cis association between the SNP rs3931020 and CRYZ gene expression levels (P = 3.68 × 10(-7)). We also found that both of these two SNPs were significantly associated with resistin gene (RETN) mRNA levels in white blood cells from 68 subjects with type 2 diabetes (both P = 0.02). In addition, the resistin-rising allele of the TYW3/CRYZ SNP rs3931020, but not the NDST4 SNP rs13144478, showed a consistent association with increased coronary heart disease risk [odds ratio = 1.18 (95% CI, 1.03-1.34); P = 0.01]. Our results suggest that genetic variants in TYW3/CRYZ and NDST4 loci may be involved in the regulation of circulating resistin levels. More studies are needed to verify the associations of the SNP rs13144478 with NDST4 gene expression and resistin-related disease.

Insulin resistance is associated with reduced serum adiponectin and increased albuminuria levels. Thus, one would anticipate an inverse relationship between circulating adiponectin and albuminuria. However, several studies have described a 'paradoxical' elevation of serum adiponectin in patients with elevated albuminuria. These findings may have been confounded by the presence of diseases and related treatments known to affect circulating adiponectin and albuminuria. We therefore studied the relationship between circulating adiponectin and albuminuria in the absence of such confounders.To this purpose, the relationship between adiponectin isoforms and albumin:creatinine ratio (ACR) was investigated in a family-based sample of 634 non-diabetic untreated white individuals with normal kidney function. We also investigated whether the two variables share a common genetic background and addressed the specific role of the gene encoding adiponectin on that background by genotyping several ADIPOQ single nucleotide polymorphisms (SNPs).ACR was directly associated with high molecular weight (HMW) adiponectin isoform (p = 0.024). The two variables shared some genetic correlation (ρ(g) = 0.38, p = 0.04). ADIPOQ promoter SNP rs17300539 was associated with HMW adiponectin (p = 4.8 × 10(-5)) and ACR (p =0.0027). The genetic correlation between HMW adiponectin and ACR was no longer significant when SNP rs17300539 was added to the model, thus reinforcing the role of this SNP in determining both traits.Our study shows a positive, independent correlation between HWM adiponectin and ACR. ADIPOQ variability is associated with HMW adiponectin and ACR, and explains some of the common genetic background shared by these traits, thus suggesting that ADIPOQ and HMW adiponectin modulate albuminuria levels.

Basic science studies have shown beneficial effects of adiponectin on glucose homeostasis, chronic low-grade inflammation, apoptosis, oxidative stress, and atherosclerotic processes, so this molecule usually has been considered a salutary adipokine. It was therefore quite unexpected that large prospective human studies suggested that adiponectin is simply a marker of glucose homeostasis, with no direct favorable effect on the risk of type 2 diabetes and cardiovascular disease. But even more unforeseen were data addressing the role of adiponectin on the risk of death. In fact, a positive, rather than the expected negative, relationship was reported between adiponectin and mortality rate across many clinical conditions, comprising diabetes. The biology underlying this paradox is unknown. Several explanations have been proposed, including adiponectin resistance and the confounding role of natriuretic peptides. In addition, preliminary genetic evidence speaks in favor of a direct role of adiponectin in increasing the risk of death. However, none of these hypotheses are based on robust data, so further efforts are needed to unravel the elusive role of adiponectin on cardiometabolic health and, most important, its paradoxical association with mortality rate.

Reduced circulating adiponectin levels contribute to the aetiology of insulin resistance. Adiponectin circulates in three different isoforms: high molecular weight (HMW), medium molecular weight (MMW) and low molecular weight (LMW) isoforms. The genetics of adiponectin isoforms is mostly unknown. Our aim was to investigate whether and to which extent circulating adiponectin isoforms are heritable and whether they share common genetic backgrounds with insulin resistance-related traits.In a family-based sample of 640 nondiabetic White Caucasians from Italy, serum adiponectin isoforms concentrations were measured by ELISA. Three single nucleotide polymorphisms (SNPs) in the ADIPOQ gene previously reported to affect total adiponectin levels (rs17300539, rs1501299 and rs677395) were genotyped. The heritability of adiponectin isoform levels was assessed by variance component analysis. A linear mixed effects model was used to test the association between SNPs and adiponectin isoforms. Bivariate analyses were conducted to study genetic correlations between adiponectin isoforms levels and other insulin resistance-related traits.All isoforms were highly heritable (h(2) = 0.60-0.80, P = 1.0 x 10(-13)-1.0 x 10(-23)). SNPs rs17300539, rs1501299 and rs6773957 explained a significant proportion of HMW variance (2-9%, P = 1.0 x 10(-3)-1.0 x 10(-5)). In a multiple-SNP model, only rs17300539 and rs1501299 remained associated with HMW adiponectin (P = 3.0 x 10(-4) and 2.0 x 10(-2)). Significant genetic correlations (P = 1.0 x 10(-2)-1.0 x 10(-5)) were observed between HMW adiponectin and fasting insulin, homeostasis model assessment of insulin resistance, HDL cholesterol and the metabolic syndrome score. Only rs1501299 partly accounted for these genetic correlations.Circulating levels of adiponectin isoforms are highly heritable. The genetic control of HMW adiponectin is shared in part with insulin resistance-related traits and involves, but is not limited to, the ADIPOQ locus.

Background Despite its beneficial role on insulin resistance and atherosclerosis, adiponectin has been repeatedly reported as an independent positive predictor of cardiovascular mortality. Methods A Mendelian randomization approach was used, in order to evaluate whether such counterintuitive association recognizes a cause-effect relationship. To this purpose, single nucleotide polymorphism rs822354 in the ADIPOQ locus which has been previously associated with serum adiponectin at genome-wide level, was used as an instrument variable. Our investigation was carried out in the Gargano Heart Study-prospective design, comprising 356 patients with type 2 diabetes, in whom both total and high molecular weight (HMW) adiponectin were measured and cardiovascular mortality was recorded (mean follow-up = 5.4 ± 2.5 years; 58 events/1922 person-year). Results The A allele of rs822354 was associated with both total and HMW adiponectin [β (SE) = 0.10 (0.042), p = 0.014 and 0.17 (0.06), p = 0.003; respectively]. In a Poisson model comprising age, sex, smoking habits, BMI, HbA1c, total cholesterol, HDL-cholesterol, triglycerides, insulin therapy and hypertension, both rs822354 (IRR = 1.94, 95 % CI 1.23–3.07; p = 0.005), as well as the genetic equivalent of total adiponectin change (IRR = 1.07, 95 % CI 1.02–1.12; p = 0.003) were significantly associated with cardiovascular mortality. The observed genetic effect was significantly greater than that exerted by the genetic equivalent change of serum adiponectin (p for IRR heterogeneity = 0.012). In the above-mentioned adjusted model, very similar results were obtained when HMW, rather than total, adiponectin was used as the exposure variable of interest. Conclusions Our data suggest that the paradoxical association between high serum adiponectin levels and increased cardiovascular mortality rate is based on a cause-effect relationship, thus pointing to an unexpected deleterious role of adiponectin action/metabolism on atherosclerotic processes.

Background The paradoxical relationship between high adiponectin and increased mortality, described in several clinical subsets, has been reported only once in type 2 diabetes (T2D) and only in selected elderly patients. We investigated this relationship in unselected patients with T2D and, then, addressed its possible modulation by several demographic and clinical conditions, known to affect per se mortality rate. Methods Patients from the Gargano Mortality Study (GMS; N = 897, follow-up = 10.5 ± 3.7 years; 290 events) and the Foggia Mortality Study (FMS; N = 529, follow-up = 7.1 ± 2.5 years; 143 events), were investigated. Results For each SD adiponectin increase, HRs (95% CI) for all-cause mortality were 1.30 (1.19–1.43) in GMS, 1.43 (1.26–1.64) in FMS and 1.34 (1.24–1.45) in the combined studies. This association was independent of the possible confounding effect of demographics, adiposity measures, diabetes-related features, kidney function-related parameters and medications (p = 9.34 × 10 −9 ). While no interaction was observed between adiponectin and sex, age, smoking habits, BMI, waist circumference, HbA1c, diabetes duration, micro-/macro-albuminuria and medications, a strong interaction was observed with GFR, with a significant adiponectin-mortality association observed in individuals with GFR≥ but not those with GFR 2 ; p for adiponectin-by-GFR status interaction = 2.13 × 10 −6 ). Conclusion This is the first study reporting a paradoxical association of adiponectin with all-cause mortality in a large sample of unselected diabetic patients and indicating that such counterintuitive effect is observed only among patients with preserved kidney function. Further studies are needed to address if the strong interwoven effect of adiponectin and GFR turns to be useful in improving previously validated tools for predicting mortality in T2D.

Our aims were to investigate in several large samples, with a wide range of adiposity, whether: (1) the effect of BMI on insulin sensitivity is different between sexes; (2) also waist circumference plays a sex-specific role on insulin sensitivity; and (3) serum adiponectin and resistin are mediators of such sex-dimorphic effect. Samples used were: Gargano study 1 (GS1), GS2 and Catania study (CS) comprising 3274 individuals. Adiponectin and resistin were measured by ELISA. Associations between variables were tested by linear models. In all samples, relationship between BMI and HOMAIR was steeper in males than in females (BMI-by-sex interaction p = 0.04–0.0007). No interaction was observed on serum adiponectin and resistin (p = 0.40–059), which are therefore unlikely to mediate the sex-dimorphic effect of BMI on insulin resistance. Relationship between waist circumference and HOMAIR was similar between sexes in GS1 and GS2 but not in CS (waist-by-sex interaction p = 0.01), comprising much heavier individuals. This suggests that a sex-dimorphic effect of abdominal adiposity on insulin resistance is observable only in the context of high BMI. Our findings represent a proof of concept that BMI and insulin sensitivity are associated in a sex-specific manner. This may explain why females are protected from diabetes and cardiovascular disease, compared to males of similar BMI.

Context: Serum levels of resistin are believed to modulate insulin resistance in humans. Objective: The aim of this study was to investigate whether serum resistin levels are genetically controlled and whether this control is shared with other insulin resistance traits. Design and Methods: The study cohort included 264 nondiabetic probands, Caucasian from Italy, and their 473 adult family members. Phenotypic characterization included anthropometric variables, blood pressure, fasting glucose and insulin, lipid profile, and resistin levels. Genotypes were determined at position g.−420C→G (rs1862513), IVS2+181G→A (rs3745367), and GAT(n) polymorphisms of the resistin (RETN) gene. Results: In the 264 unrelated probands, resistin levels were significantly (P < 0.01) correlated with adiposity, blood pressure, C-reactive protein, and the metabolic syndrome score. In a variance component analysis of the 264 probands and their 473 relatives, about 70% of the observed variation of serum resistin levels was heritable (P < 0.0001). A small, but significant (P = 0.004) proportion of this variance was explained by the G→A variation at position IVS2+181 of the RETN gene. Significant genetic correlations (P < 0.05) were observed between resistin and body mass index (ρg = 0.30), waist circumference (ρg = 0.32), the insulin resistance index HOMAIR (ρg = 0.28), and the metabolic syndrome score (ρg = 0.35). Conclusions: These data indicate that serum resistin is highly heritable and has some common genetic background with traits related to insulin resistance, reinforcing the hypothesis that this adipokine may play a pathogenic role in insulin resistance-related abnormalities, including type 2 diabetes and cardiovascular disease.

Inhibiting Galpha subunit 2 protein, which is encoded by the GNAI2 gene, is suggested to be pathogenic for essential hypertension and/or insulin resistance. The aim of this study was to determine whether GNAI2 variations modulate the risk for these abnormalities. Seven single-nucleotide polymorphisms (SNP) at the GNAI2 locus were identified. Because of either low allelic frequency or unlikely biologic relevance (i.e., synonymous or intronic), six SNP were not studied further. The -318CG SNP (allelic frequency 6%) in the promoter region was studied for association with adiposity, systolic BP (SBP) and diastolic BP, fasting insulin and glucose, and lipids levels in 655 nondiabetic Caucasians from Italy. As compared with individuals who carry the C/C genotype, G carriers (i.e., individuals who carry either the G/G or the C/G genotype) had higher SBP (117.8 +/- 16 versus 113.6 +/- 12.6 mmHg; P = 0.010) and were at increased risk for hypertension (odds ratio 2.2; 95% confidence interval 1.1 to 4.5). Compared with the C, the G allele had 2.5-fold reduced transcriptional activity in transfected HEK293 cells. As predicted by the TRANSFAC database, competition with YY1 or Sp1 transcription factors specifically reduced the binding of HeLa cell nuclear proteins to -318C or -318G allele, respectively, as indicated by shifted electrophoretic mobility. A "supershift" of the nuclear proteins/-318G allele complex was observed after anti-Sp1 was added but not anti-YY1 antibody. The GNAI2 -318 CG SNP impairs transcriptional activity through specific binding of Sp1 and is associated with high SBP in Caucasians from Italy.

Context Studies concerning the association between circulating resistin and mortality risk have reported, so far, conflicting results. Objective To investigate the association between resistin and both all-cause and cardiovascular (CV) mortality risk by 1) analyzing data from the Gargano Heart Study (GHS) prospective design (n=359 patients; 81 and 58 all-cause and CV deaths, respectively); 2) performing meta-analyses of all published studies addressing the above mentioned associations. Data Source and Study Selection MEDLINE and Web of Science search of studies reporting hazard ratios (HR) of circulating resistin for all-cause or CV mortality. Data Extraction Performed independently by two investigators, using a standardized data extraction sheet. Data Synthesis In GHS, adjusted HRs per one standard deviation (SD) increment in resistin concentration were 1.28 (95% CI: 1.07-1.54) and 1.32 (95% CI: 1.06-1.64) for all-cause and CV mortality, respectively. The meta-analyses included 7 studies (n=4016; 961 events) for all-cause mortality and 6 studies (n=4,187: 412 events) for CV mortality. Pooled HRs per one SD increment in resistin levels were 1.21 (95% CI: 1.03-1.42, Q-test p for heterogeneity

Background High serum levels of the pro-inflammatory adipokine resistin have been associated with decreased renal function in the general population. The goal of this study was to investigate whether such association is also present among diabetic subjects, who are at increased risk of renal function loss. Methods The cross-sectional association between serum resistin levels and estimated glomerular filtration rate (eGFR) was investigated in 1,560 type 2 diabetic (T2D) patients of European ancestry comprised in two different cohorts: 762 patients from San Giovanni Rotondo (SGR; Italy) and 798 patients from Boston (US). Results Serum resistin was inversely associated with eGFR in SGR [β (SE) for one SD of resistin increment = -1.01 (0.70) ml/min/1.73m2, p = 0.019] and in Boston [β (SE) = -5.31 (0.74) ml/min/1.73m2, p < 0.001] samples, as well as in the two studies combined [β (SE) = -3.42 (0.52) ml/min/1.73m2, p < 0.001]. The association was unaffected by adjustment for smoking habits, BMI, waist circumference, diabetes duration, HbA1c, insulin treatment, hypertension and lipid-lowering therapy: β (SE) for one SD of resistin increment = -1.07 (0.70), p = 0.02; -5.50 (0.88), p < 0.001; and -2.81 (0.55) ml/min/1.73m2, p < .001, in SGR, Boston and the two studies combined, respectively. The association was significantly stronger in men than in women (p for resistin-by-gender interaction = 0.003). For each resistin SD increment, the odds of having eGFR < 0 ml/min/1.73m2 increased by 22% (OR = 1.22; 95% CI 1.02–1.44; p = 0.025) in SGR sample, 69% (OR = 1.69; 95% CI 1.38–2.07; p < 0.001) in Boston sample, and 47% (OR = 1.47; 95% CI 1.29–1.68; p < 0.001) in the two studies considered together. Similar associations were observed in the adjusted model: OR 95% CI for each SD resistin increment being 1.23 (1.03–1.46), p = 0.021; 1.52 (1.20–1.92), p < 0.001; 1.33 (1.16–1.53), p < 0.001, in SGR, Boston and the two studies combined, respectively. Conclusions This is the first report of an association between high serum resistin and low eGFR in patients with T2D of European ancestry.

High serum adiponectin has been increased in several conditions of kidney disease. Only sparse and conflicting results have been reported in patients with type 2 diabetes (T2D), a subgroup of individuals who are at high risk for renal dysfunction. The aim of this study was to fill up this gap of knowledge by investigating such association in a large sample of Italian diabetic patients. The association between serum adiponectin levels and estimated glomerular filtration rate (eGFR by Chronic Kidney Disease-Epidemiology Collaboration CKD-EPI equation) was investigated in 1,243 patients with T2D from two cross-sectional Italian studies: 878 from San Giovanni Rotondo (SGR) and 365 from Foggia (FG). Serum adiponectin was inversely associated with eGFR in SGR [β (standard error, SE) for 1 standard deviation (SD) of adiponectin = -3.26 (0.64)] and in FG [β(SE)=-5.70(1.28)] sample, as well as in the two studies combined [β(SE)=-3.99(0.59)];(p

Recent evidence indicates that IB kinase (Ikk) may be a mediator of acquired forms of insulin-resistance. In this study, we examined whether genetic variability at the Ikk locus (IKBKB) contributes to the development of genetic forms of early-onset type 2 diabetes transmitted with an autosomal dominant mode of inheritance. Linkage with four markers flanking the IKBKB gene was evaluated in 32 multigenerational families. Included in the study were 233 diabetic (mean age at Dx 37 18) and 152 nondiabetic subjects. The overall LOD scores were negative (54.9 and 46.2 on the centromeric and telomeric sides, respectively) indicating that variability in IKBKB was not a major determinant of diabetes in these families. Positive values, however, were observed for selected pedigrees. All 17 families for which linkage with the IKBKB locus could not be excluded were screened for sequence differences in the 22 exons and 1.6 kb of the 5 flanking region by dideoxyfingerprinting or direct sequencing. Polymorphisms were identified in the 5 flanking region (1775del/insC and 1547T > A), exon 11 (c.1083A > G, L361L) and in intron 12 (IVS1214t > a). However, no mutations segregating with diabetes could be found in these families. Furthermore, all four polymorphisms had similar allele frequencies in the 32 family probands, 171 individuals with common, later-onset type 2 diabetes, and 182 nondiabetic controls. We conclude that sequence differences in the IKBKB gene do not play a major role in either early-onset, autosomal dominant type 2 diabetes, or common forms with a later-onset. (J Clin Endocrinol Metab 87: 1894 –1897, 2002)

Maturity-onset diabetes of the young (MODY; MIM# 606391) is a genetically and clinically heterogeneous form of diabetes, accounting for 1–2% of all diabetes cases (1). MODY is characterized by mild hyperglycemia or overt diabetes usually detected in three consecutive generations, with onset before the age of 25 years and absence of type 1 diabetes autoantibodies. Among the thirteen MODY genes identified, two subtypes, GCK -MODY and HNF1A -MODY, account for most of cases (1). The prevalence of GCK -MODY has been reported higher in Southern Europe (2), while HNF1A -MODY is the most common MODY subtype in Northern Europe (3). This difference might be attributable to the clinical setting in which genetic screening is performed, especially when pediatric and adult diabetes clinics are distinct entities. We addressed this issue by investigating MODY patients identified in the pediatric or in the adult diabetes clinics of the same research-based …

Background The pathogenesis of cardiovascular (CV) mortality, whose rate is increased in type 2 diabetes, is poorly understood. While high serum adiponectin is associated with increased CV mortality in the general population, no data are available in type 2 diabetes. We here investigated whether this counterintuitive association was observable also in diabetic patients and whether it was sex-specific. Methods Three prospective cohorts were analyzed: 1) Gargano Heart Study (GHS; 359 patients, 58 events/1,934 person-years; py); 2) Health Professional Follow-up Study (HPFS; 833 men, 146 events/10,024 py); 3) Nurses’ Health Study (NHS; 902 women, 144 events/15,074 py). Results In GHS serum adiponectin predicted CV mortality in men (hazard ratio, HR, and 95% CI per standard deviation, SD, increment = 1.54, 1.19-2.01), but not women (HR = 0.98, 0.48-2.01). Circulating adiponectin predicted CV mortality in men from HPFS (HR = 1.44, 1.21-1.72), but not in women from NHS (HR = 1.08, 0.86-1.35), used as replication samples. In a pooled analysis, HRs were 1.47 (1.27-1.70) in 1,075 men and 1.07 (0.86-1.33) in 1,019 women (p for HRs heterogeneity across sexes = 0.018). Conclusions This is the first report showing that high circulating adiponectin predicts increased CV mortality in men, but not in women with type 2 diabetes. Further studies are necessary to unravel the mechanisms through which adiponectin influences CV mortality in a sex-specific manner. Electronic supplementary material The online version of this article (doi:10.1186/s12933-014-0130-y) contains supplementary material, which is available to authorized users.

We describe a diabetic child and her relatives carrying the HNF4A R311H mutation. The proband was diagnosed with insulin-dependent diabetes when 9.1 year-old. Three weeks later, a complete remission occurred. She underwent genetic testing showing the HNF4A-R311H mutation, which was found also in the brother (with impaired glucose tolerance), the mother (with gestational diabetes), and the maternal uncle (with type 2 diabetes). This case suggests that the HNF4A R311H mutation may play a role on hyperglycaemia since childhood and may be associated with clinical heterogeneity of abnormal glucose homeostasis. Transient diabetes might warrant the screening for MODY when indicated.

Keywords Insulinresistance.Population-specificeffect.Resistincirculatinglevels.RETNAdipocytes release a number of peptide hormones, collec-tively known as adipokines, which are essential inregulation of intermediate metabolism, and which maycontribute to the pathogenesis of insulin resistance andrelated disorders [1].Among these is resistin, a 12.5 kDa cysteine-rich proteinthat is secreted also by macrophages [2–4]. Several piecesof evidence suggest that this molecule antagonises insulinaction and fosters inflammation [2–4]. In humans, mostcross-sectional studies have reported that elevated resistinlevels are associated with insulin resistance [5–7] and type2 diabetes [8]. In most [9–11], although not all [12],prospective studies, resistin turned out to be a predictor oftype 2 diabetes and cardiovascular disease. Taken together,these findings highlight the role of serum resistin as anemerging pathogenic factor and a potential therapeutictarget for insulin resistance-related disorders. This latterpossibility is reinforced by the observation that resistinexpression in human adipose tissue is inhibited bythiazolidinediones [13], insulin-sensitising molecules thatare used as oral hypoglycaemic agents in the treatment ofpatients with type 2 diabetes.The mechanisms regulating resistin expression, secretionand circulating levels are still poorly understood. Recentdata clearly indicate that resistin serum levels are undergenetic control [6, 14]. Several single-nucleotide poly-morphisms (SNPs) in the RETN gene coding for resistin,have been associated with serum resistin levels and insulinresistance traits [6 ,8 14–18].Among others, rs1862513 at position g.−420 in theRETN 5′ flanking region has attracted much attention. ThisSNP has been associated with high resistin levels [8, 16],insulin resistance [ 17], obesity [15 , 18] and type 2diabetes [8, 19]. A recent meta-analysis, including morethan 3,500 individuals, has shown that those homozygousfor the G allele at rs1862513 have a 30% increase in theodds of being affected by type 2 diabetes [8]. Along thesame lines, the G allele was predictive of glycaemicdeterioration in a Chinese population followed for 5 years[20]. These associations are supported by functional datademonstrating a stronger activation of the RETN promoterby Sp1 and Sp3 transcription factors in the presence of theG allele [8]. In agreement with these data, the same allelehas been reported to be associated with higher abdominal-fat resistin mRNA levels [21]. Thus, so far, so good forSNP rs1862513.Recently, a fine-mapping analysis of the RETN gene hasbeen carried out in a sample of more than 2,500 individualsof European ancestry [14]. The authors found that alleles at

Thyroid-stimulating IgG from Graves’ patients bind to the TSH receptor and activate both adenylyl cyclase (AC) and phospholipase A2 (PLA2) in FRTL5 thyroid cells. Both activities have been associated with increased thyroid cell growth and function; evidence exists that subpopulations of Graves’ IgG can stimulate either AC or PLA2 cascades and that the activation of both is associated with the largest goiters in patients. Studies using chimeras of the human TSHR receptor (hTSHR) and the LH-CG receptor show that most patients with Graves’ disease have cAMP-stimulating IgG that require epitopes on the N-terminal portion of the TSHR extracellular domain; epitopes associated with PLA2 activation are not clear. To address this question we used stably transfected Chinese hamster ovary (CHO) cells containing the wild-type hTSHR and the hTSHR chimera with residues 8–165 (Mc1+2) substituted by equivalent residues of the LH-CG receptor. PLA2 activity, measured as arachidonic acid (AA) release, was determined in 32 p...