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Diabetic foot syndrome (DFS) is a complex disease. The best outcomes are reported with the multi-disciplinary team (MDT) approach, where each member works collaboratively according to his/her expertise. However, which health provider should act as the team leader (TL) has not been determined. The TL should be familiar with the management of diabetes, related complications and comorbidities. He/she should be able to diagnose and manage foot infections, including prompt surgical treatment of local lesions, such as abscesses or phlegmons, in an emergent way in the first meeting with the patient. According to the Organization for Economic Co-operation and Development (OECD) reports, Italy is one of countries with a low amputation rate in diabetic patients. Many factors might have contributed to this result, including 1)the special attention directed to diabetes by the public health system, which has defined diabetes as a "protected disease", and accordingly, offers diabetic patients, at no charge, the best specialist care, including specific devices, and 2)the presence of a network of diabetic foot (DF) clinics managed by diabetologists with medical and surgical expertise. The health care providers all share a "patient centred model" of care, for which they use their internal medicine background and skills in podiatric surgery to manage acute or chronic needs in a timely manner. Therefore, according to Italian experiences, which are fully reported in this document, we believe that only a skilled diabetologist/endocrinologist should act as a TL. Courses and university master's degree programmes focused on DF should guarantee specific training for physicians to become a TL.

Context Genes causing familial forms of diabetes mellitus are only partially known. Objective We set out to identify the genetic cause of hyperglycemia in multigenerational families with an apparent autosomal dominant form of adult-onset diabetes not due to mutations in known monogenic diabetes genes. Methods Existing whole-exome sequencing (WES) data were used to identify exonic variants segregating with diabetes in 60 families from the United States and Italy. Functional studies were carried out in vitro (transduced MIN6-K8 cells) and in vivo (Caenorhabditis elegans) to assess the diabetogenic potential of 2 variants in the malate dehydrogenase 2 (MDH2) gene linked with hyperglycemia in 2 of the families. Results A very rare mutation (p.Arg52Cys) in MDH2 strongly segregated with hyperglycemia in 1 family from the United States. An infrequent MDH2 missense variant (p.Val160Met) also showed disease cosegregation in a family from Italy, although with reduced penetrance. In silico, both Arg52Cys and Val160Met were shown to affect MDH2 protein structure and function. In transfected HepG2 cells, both variants significantly increased MDH2 enzymatic activity, thereby decreasing the NAD+/NADH ratio—a change known to affect insulin signaling and secretion. Stable expression of human wild-type MDH2 in MIN6-K8 cell lines enhanced glucose- and GLP-1-stimulated insulin secretion. This effect was blunted by the Cys52 or Met160 substitutions. Nematodes carrying equivalent changes at the orthologous positions of the mdh-2 gene showed impaired glucose-stimulated insulin secretion. Conclusion Our findings suggest a central role of MDH2 in human glucose homeostasis and indicate that gain of function variants in this gene may be involved in the etiology of familial forms of diabetes.

Background and aims Diabetic foot (DF) disease is a current health and social burden. The authors aimed to identify the barriers to the DF management across Italy. Methods and results A questionnaire was submitted to Italian centres dedicated to DF care. The questionnaire was composed of 12 questions focused on the barriers to the DF management including timing of referral, hospital management, and community follow-up. Each centre could answer by choosing a score from 1 to 5 for every item with the following numerical variables: 1 = never; 2 = rarely; 3 = sometimes; 4 = often; 5 = always. Accordingly, for each item a national and regional score was reported and a comparison between regions was carried out. National and regional scores were estimated using the total score for each item as a numerator and the number of national centres included as a denominator. Among 102 centres, 99 were included and 3 were excluded due to missing data. The 99 centres belonged to 16 regions with the following distribution: Calabria 4, Campania 5, Emilia-Romagna 14, Friuli-Venezia-Giulia 4, Lazio 12, Liguria 4, Lombardy 10, Marche 1, Molise 1, Piedmont 5, Apulia 5, Sardinia 5, Sicily 4, Tuscany 11, Veneto 9, Umbria 5. The items with the highest score were late referral (3.3) and urgent surgery (3.2). The regions with the highest score were Molise (3.9) and Calabria (3.5). Conclusion The main issues across Italy were late referral and the requirement for urgent surgery for acute DF. In the regional scenario, the southern central areas showed more barriers than northern regions.

Multigenerational diabetes of adulthood is a mostly overlooked entity, simplistically lumped into the large pool of type 2 diabetes. The general aim of our research in the past few years is to unravel the genetic causes of this form of diabetes. Identifying among families with multigenerational diabetes those who carry mutations in known monogenic diabetes genes is the first step to then allow us to concentrate on remaining pedigrees in which to unravel new diabetes genes. Targeted next-generation sequencing of 27 monogenic diabetes genes was carried out in 55 family probands and identified mutations verified among their relatives by Sanger sequencing. Nine variants (in eight probands) survived our filtering/prioritization strategy. After likelihood of causality assessment by established guidelines, six variants were classified as “pathogenetic/likely pathogenetic” and two as “of uncertain significance.” Combining present results with our previous data on the six genes causing the most common forms of maturity-onset diabetes of the young allows us to infer that 23.6% of families with multigenerational diabetes of adulthood carry mutations in known monogenic diabetes genes. Our findings indicate that the genetic background of hyperglycemia is unrecognized in the vast majority of families with multigenerational diabetes of adulthood. These families now become the object of further research aimed at unraveling new diabetes genes.

The aim of this article was to share with a wide readership some data and related reasoning about a multigenerational form of diabetes mellitus of adulthood.We have recently described a familial form of diabetes mellitus, which in the routine clinical setting of adult individuals is simplistically diagnosed as type 2 diabetes. Such misdiagnosis involves as much as 3% of adult unrelated diabetic patients with no evidence of autoimmune disease. More recent data, obtained by means of a next-generation sequencing, indicate that approximately 25% of such patients carry mutations in the genes involved in monogenic diabetes, thus leaving unraveled the molecular causes of the remaining 75% individuals.Our proposal is to define the latter patients as being affected by familial diabetes of adulthood (FDA), a clear admission of ignorance and a limbo where adult patients with multigenerational diabetes with no genetic definition of their hyperglycemia have to wait for better times.

Mutations in the glucokinase (GCK) gene are the most frequent cause of maturity onset diabetes of the young (MODY) in Italy. We evaluated GCK mutations in 32 unrelated patients younger than 18 years who had been diagnosed with MODY. Eleven different GCK heterozygous mutations were identified in 22 (68.7%) of the 32 probands. Nine mutations were missense and two were nonsense. Three of these mutations (E17X, P59S and E372X) have not been described previously and were shown to be associated with hyperglycaemia. Several prediction methods suggested that the E17X and E372X mutations result in a premature truncated protein and that the P59S mutation is pathogenic. This idea was further supported by evidence suggesting that Proline 59 is a highly conserved amino acid residue and that the P59S mutation does not appear to be present in non-diabetic controls and in sequence variant databases. Furthermore, this mutation was found in six (27.3%) of the patients from the same geographical area, Gargano, pointing to the existence of a founder effect, which was confirmed by microsatellite analysis.

Diabetes mellitus is a highly heterogeneous disorder encompassing several distinct forms with different clinical manifestations including a wide spectrum of age at onset. Despite many advances, the causal genetic defect remains unknown for many subtypes of the disease, including some of those forms with an apparent Mendelian mode of inheritance. Here we report two loss-of-function mutations (c.1655TA [p.Leu552(∗)] and c.280GA [p.Asp94Asn]) in the gene for the Adaptor Protein, Phosphotyrosine Interaction, PH domain, and leucine zipper containing 1 (APPL1) that were identified by means of whole-exome sequencing in two large families with a high prevalence of diabetes not due to mutations in known genes involved in maturity onset diabetes of the young (MODY). APPL1 binds to AKT2, a key molecule in the insulin signaling pathway, thereby enhancing insulin-induced AKT2 activation and downstream signaling leading to insulin action and secretion. Both mutations cause APPL1 loss of function. The p.Leu552(∗) alteration totally abolishes APPL1 protein expression in HepG2 transfected cells and the p.Asp94Asn alteration causes significant reduction in the enhancement of the insulin-stimulated AKT2 and GSK3β phosphorylation that is observed after wild-type APPL1 transfection. These findings-linking APPL1 mutations to familial forms of diabetes-reaffirm the critical role of APPL1 in glucose homeostasis.

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 …

Conflicting results have been reported regarding the effect of the peroxisome proliferator-activated receptor-gamma-2 (PPARgamma2) Pro12Ala polymorphism, (singly or in combination with the silent C1431T polymorphism) on BMI. Gender-based dimorphism has been evidenced for genes that affect BMI, but few and conflicting data are available regarding PPARgamma2. We sought to investigate whether the Pro12Ala interacts with gender in modulating BMI in 566 nondiabetic unrelated white subjects (men:women = 211:355, age 36.59 +/- 11.85; BMI 25.36 +/- 4.53). In the whole study population, BMI, fasting glucose and insulin levels, and lipid profile were similar in Ala12 carriers (i.e., XA) and Pro/Pro homozygous subjects. Among the men, but not among the women, X/Ala individuals showed higher BMI (25.9 +/- 3.6 vs. 28.2 +/- 4.9, P = 0.006) and risk of obesity (odds ratio = 2.85, 95% confidence interval = 1.07-7.62). A significant gene-gender interaction in modulating BMI was observed (P = 0.039). Among the men, but not among the women, those carrying Ala-T haplotype (i.e., containing both Ala12 and T1431 variants) showed the highest BMI (haplo-score = 3.72, P = 0.0014). Our data indicate that in whites from Italy the PPARgamma2 Pro12Ala polymorphism interacts with gender in modulating BMI, thereby replicating some, but not all, earlier data obtained in different populations. Whether the PPARgamma2-gender interaction is a general phenomenon across different populations, is still an open question, the answer to which requires additional, specifically designed, studies.

Conflicting results have been reported regarding whether the PPARgamma2 Pro12Ala polymorphism plays a role in the risk of type 2 diabetes (T2D), suggesting genetic heterogeneity. To investigate this issue, a meta-analysis of 41 published and 2 unpublished studies (a total of 42,910 subjects) was conducted. Ala12 carriers had a 19% T2D risk reduction, but this association was highly heterogeneous (p = 0.005). A great proportion (48%) of heterogeneity was explained by the controls' BMI, with risk reduction being greater when BMI was lower. Risk reduction of Ala12 carriers in Asia (35%) was higher than in Europe (15%, p = 0.02) and tended to be higher than in North America (18%, p = 0.10). Difference between Asians and Europeans was no longer significant (p = 0.15) after adjusting for the controls' BMI. Studies from Europe were still heterogeneous (p = 0.02) with risk reduction in Ala12 carriers being progressively smaller (test for trend in the odds ratios, p = 0.02) from Northern (26% reduction, p < 0.0001) to Central (10%, p = 0.04) and Southern (0%, p = 0.94) Europe. In conclusion, in our meta-analysis, the reduced risk of T2D in Ala12 carriers is not homogeneous. It is greater in Asia than in Europe and, among Europeans, it is higher in Northern Europe, barely significant in Central Europe, and nonexistent in Southern Europe.

Insulin resistance (IR) is pathogenic for type 2 diabetes and coronary artery disease (CAD). The K121Q polymorphism of the ENPP1/PC-1 gene is associated with IR. Our aim was to investigate the role of the 121Q variant on the risk of type 2 diabetes and CAD. Nondiabetic control subjects (n = 638), type 2 diabetic patients without CAD (n = 535), and type 2 diabetic patients with CAD (n = 434) from Italy and the U.S. were studied. The proportion of 121Q carriers progressively increased in the three groups (27.4, 28.8, and 33.2%, respectively; adjusted P value = 0.027). Among diabetic patients (n = 969), 121Q carriers had an increased risk of developing type 2 diabetes before the age of 65 years (adjusted odds ratio [OR] 2.26, 95% CI 1.26–4.03; P = 0.006) and having a myocardial infarction (MI) (n = 156) by 50 years of age (3.17, 1.46–6.88, P = 0.007). The 121Q variant was also associated with an increased risk for CAD (1.47, 1.01–2.18; P = 0.049) in diabetic patients who did not smoke (n = 546). In conclusion, the ENPP1/PC-1 121Q variant is associated with a progressive deterioration of the IR-atherogenic phenotype; among diabetic individuals, it is also associated with earlier onset of type 2 diabetes and MI.

Uncoupling protein-2 (UCP2) regulates insulin secretion and may play an important role in linking obesity to type 2 diabetes (T2D). Previous studies of the role of the UCP2 promoter -866G/A single nucleotide polymorphisms (SNP) in T2D have given opposite results. We tested the distribution of the -866G/A SNP in 746 T2D patients and 327 healthy unrelated Caucasians from Italy. We also tested for an effect of the P12A variant of the peroxisomal proliferator-activated receptor-gamma 2 (PPAR gamma 2) gene on diabetes risk given by the UCP2 SNP. Compared with -866G/G carriers, a progressively reduced (P = 0.01) risk of T2D was observed in -866G/A and -866A/A subjects, with the latter showing an approximately 50% risk reduction [odd ratio (OR), 0.51; 95% confidence interval (CI), 0.3-0.8; P = 0.003]. Conversely, the -866G/G genotype was associated with increased risk (OR, 1.31; 95% CI, 1.01-1.71). Overall, the population risk attributable to the UCP2 -866G/G genotype was about 12%. After stratifying for the PPAR gamma 2 polymorphism, the increased risk conferred by the UCP2 G/G genotype was still evident among P12/P12 homozygous subjects (n = 801; OR, 1.38; 95% CI, 1.04-1.83), but seemed to disappear among the X12/A12 subjects (i.e. P12/A12 heterozygous or A12/A12 homozygous subjects; n = 137; OR, 0.87; 95% CI, 0.40-1.91). Whether this apparent difference is entirely due to the different number of carriers of the two PPAR gamma 2 genotypes is a likely possibility that deserves deeper investigation. In conclusion, in our population, the -866G/A SNP is associated with T2D. Additional studies in larger samples are needed to investigate the possibility of a concomitant effect of modifier genes such as PPAR gamma 2.

Insulin resistance, which is pathogenic for type 2 diabetes (T2D), is under the control of largely unknown genetic determinants. LAR, a protein-tyrosine phosphatase which inhibits insulin signalling, is overexpressed in animal and human models of insulin resistance. We studied the entire sequence of the LAR gene by SSCP analysis and automatic DNA sequencing, with the aim of verifying whether its sequence variants might be associated with insulin resistance. In the 276 bp sequence upstream of the transcriptional start site (i.e. a region we have identified as having basal promoter activity) a -127 bp T--A SNP (5% frequency) was associated with lower body mass index (BMI) ( P=0.03), waist circumference ( P=0.01), blood pressure ( P=0.01) and urinary albumin/creatinine ratio ( P=0.04) in 589 non-diabetic unrelated individuals from the Gargano region (central east coast of Italy). To quantify the risk for a high body weight conferred by the -127 T--A SNP, the whole cohort was divided into tertiles according to the individual BMI. The risk of belonging to the heavier tertile, as compared to the leaner one, was reduced by approximately 60%. In a population from East Sicily ( n=307), T/A genotype carriers ( n=13) showed lower triglyceride levels ( P=0.04) and higher insulin sensitivity as indicated by lower plasma glucose ( P=0.03) and serum insulin ( P=0.006) during oral glucose tolerance testing (OGTT). Promoter activity, studied by cDNA transfection experiments, was similar for the A and T alleles. In conclusion, a genetic variant of the LAR gene promoter is consistently associated with features of insulin resistance in two different Caucasian populations. Although the biological relevance of this variant has yet to be determined, this finding underlines the potential importance of the LAR gene in dysregulation of insulin sensitivity and related disorders.

Ten additional adrenocortical oncocytic tumors are presented: 2 benign oncocytomas, 4 borderline oncocytomas of uncertain malignant potential, and 4 oncocytic carcinomas. Histologically all tumors were entirely or predominantly composed of oncocytes. Immunohistochemically all tumors were immunoreactive for mitochondrial antigen mES-13. Electron microscopy was performed in 8 cases and was confirmatory of the oncocytic cell change. The morphologic parameters of the Weiss system, considered to be predictive of the biologic behavior of conventional (nononcocytic) adrenocortical tumors, are reviewed in the context of their possible application to the oncocytic tumor variant. Proposed major criteria (high mitotic rate, atypical mitoses, venous invasion) and minor criteria (large size and huge weight, necrosis, capsular invasion, sinusoidal invasion) in distinguishing malignant tumors are discussed, and definitional criteria (predominantly cells with eosinophilic and granular cytoplasm, high nuclear grade, diffuse architectural pattern) in common with all types of oncocytic tumors are outlined. The authors’ proposed working rules for diagnostic categorization of oncocytic adrenocortical tumors are defined, with the presence of 1 major criterion indicating malignancy, 1 to 4 minor criteria indicating uncertain malignant potential (borderline), and the absence of all major and minor criteria indicative of benignancy. Using these criteria, the diagnosis of malignancy was straightforward in 3 of the 4 cases designated as oncocytic carcinoma (presence of at least 2 major criteria and all the minor criteria), while in 1 case the original diagnosis of benign oncocytoma was reversed to malignant following critical review of the original pathologic material after local tumor recurrence. Tumor recurrence occurred in 2 carcinomas at 8 and 20 months, respectively, and was followed in 1 case by the patient’s death. The third patient expired at 6 months from unrelated causes, and the fourth patient is free of disease at the relatively short follow-up interval of 6 months. Regarding the 4 patients with borderline tumors, all are alive with no evidence of disease, with follow-up ranging from 10 to 61 months (mean 38.7 months). The 2 benign tumors have a follow-up of 25 and 30 months, respectively. Diagnostic difficulties are delineated and a complete review of the literature on this topic has also been performed.