Brain effect of bariatric surgery in people with obesity.

BACKGROUND/OBJECTIVES: The link between obesity and brain function is a fascinating but still an enigmatic topic. We evaluated the effect of Roux-en-Y gastric bypass (RYGB) on peripheral glucose metabolism, insulin sensitivity, brain glucose utilization and cognitive abilities in people with obesity. SUBJECTS/METHODS: Thirteen subjects with obesity (F/M 11/2; age 44.4 ± 9.8 years; BMI 46.1 ± 4.9 kg/m2) underwent 75-g OGTT during a [18F]FDG dynamic brain PET/CT study at baseline and 6 months after RYGB. At the same timepoints, cognitive performance was tested with Mini Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Trail making test (TMT) and Token test (TT). Glucose, insulin, C-peptide, GLP-1, GIP, and VIP levels were measured during OGTT. Leptin and BDNF levels were measured before glucose ingestion. RESULTS: RYGB resulted in significant weight loss (from 46.1 ± 4.9 to 35.3 ± 5.0 kg/m2; p < 0.01 vs baseline). Insulin sensitivity improved (disposition index: from 1.1 ± 0.2 to 2.9 ± 1.1; p = 0.02) and cerebral glucose metabolic rate (CMRg) declined in various brain areas (all p ≤ 0.01). MMSE and MoCA score significantly improved (p = 0.001 and p = 0.002, respectively). TMT and TT scores showed a slight improvement. A positive correlation was found between CMRg change and HOMA-IR change in the caudate nucleus (ρ = 0.65, p = 0.01). Fasting leptin decreased (from 80.4 ± 13.0 to 16.1 ± 2.4 ng/dl; p = 0.001) and correlated with CMRg change in the hippocampus (ρ = 0.50; p = 0.008). CMRg change was correlated with cognitive scores changes on the TMT and TT (all p = 0.04 or less). CONCLUSIONS: Bariatric surgery improves CMRg directly related to a better cognitive testing result. This study highlights the potential pleiotropic effects of bariatric surgery. TRIAL REGISTRY NUMBER: NCT03414333.

Efficacy of Dulaglutide in a Patient With Type 2 Diabetes, High Cardiovascular Risk, and HIV: A Case Report.

Background: Type 2 diabetes (T2D) is a common comorbidity in people living with HIV (PLWH). Anti-hyperglycemic treatment in PLWH is still a challenge, and no randomized controlled studies using new glucose-lowering agents are currently available. Case Description: A 55-year-old-women was admitted to our Diabetes Unit because of hyperosmolar hyperglycemic state (HHS) and sepsis. The medical history included HIV infection and insulin-treated diabetes. On clinical examination, the lady appeared dehydrated with dry buccal mucosa, tachycardia, altered mental status, genital infection, and fever. On admission, plasma glucose was 54.5 mmol/L, HbA1c 155 mmol/mol, osmolarity 389.4 mOsm/kg, bicarbonate 24.6 mmol/L with no detectable serum ketones. The patient was treated with i.v. fluid and insulin, and antibiotic therapy commenced. Upon HHS and sepsis resolution, a basal-bolus insulin therapy was implemented that was followed by significant improvement of daily glucose profiles and progressive reduction of insulin requirement until complete discontinuation. A low dose of metformin plus linagliptin was started. Since a severe atherosclerotic disease was diagnosed, a GLP-1 receptor agonist, dulaglutide, was added to metformin upon linagliptin withdrawal with maintenance of good glycemic control, treatment adherence and amelioration of quality of life and no side effects. Conclusion: This case suggests that GLP-1 receptor agonist therapy may be effective and safe for treatment of T2D with high cardiovascular risk in PLWH, supporting the need of clinical trials directly assessing the safety and the efficacy of GLP-1 receptor agonist in these individuals.

Bariatric surgery restores visual cortical plasticity in nondiabetic subjects with obesity.

BACKGROUND/OBJECTIVES: Obesity leads to changes in synaptic plasticity. We aimed at investigating the impact of bariatric surgery (RYGB) on visual neural plasticity (NP) and its relationship with the main gut peptides, leptin, and brain-derived neurotrophic factor (BDNF). SUBJECTS/METHODS: NP was assessed testing binocular rivalry before and after 2 h of monocular deprivation (index of visual brain plasticity) in 15 subjects with obesity (age 42.3 ± 9.8 years; BMI 46.1 ± 4.9 kg/m2) before and after RYGB. Gut peptides, leptin, and BDNF were obtained at baseline and 6 months after surgery in 13 subjects. RESULTS: A significant reduction in BMI (p < 0.001 vs. baseline) and a significant increase of disposition index (DI, p = 0.02 vs baseline) were observed after RYGB. Total and active GLP-1 release in response to glucose ingestion significantly increased after RYGB, while no changes occurred in VIP, GIP, and BDNF levels. Fasting leptin concentration was lower after RYGB (p = 0.001 vs. baseline). Following RYGB, NP was progressively restored (p < 0.002). NP was correlated with DI and fasting glucose at baseline (r = 0.75, p = 0.01; r = -0.7, p = 0.02; respectively), but not with BMI. A positive correlation between post-pre-RYGB changes in AUCactive GLP-1 and NP was observed (r = 0.70, p < 0.01). Leptin was inversely correlated with NP 6 months after surgery (r = -0.63, p = 0.02). No correlation was observed between GIP, VIP, BDNF, and NP. CONCLUSIONS: Visual plasticity is altered in subjects with obesity, and it can be restored after RYGB. The improvement may be mediated by amelioration of insulin sensitivity, increased GLP-1 levels, and reduced leptin levels.

Nesidioblastosis and Insulinoma: A Rare Coexistence and a Therapeutic Challenge.

Background: Nesidioblastosis and insulinoma are disorders of the endocrine pancreas causing endogenous hyperinsulinemic hypoglycemia. Their coexistence is very unusual and treatment represents a still unresolved dilemma. Case Description: The patient was a 43-year-old Caucasian woman, with a 2-year history of repeated severe hypoglycemic events. The diagnostic work-up was strongly suggestive of insulinoma and the patient was submitted to surgical treatment carried out laparoscopically under robotic assistance. However, surgical exploration and intraoperative ultrasonography failed to detect a pancreatic tumor. Resection was therefore carried out based on the results of selective intra-arterial calcium stimulation test, following a step-up approach, eventually leading to a pancreatoduodenectomy at the splenic artery. The histopathology examination and the immunohistochemical staining were consistent with adult-onset nesidioblastosis. After surgery, the patient continued to experience hypoglycemia with futile response to medical treatments (octreotide, calcium antagonists, diazoxide, and prednisone). Following multidisciplinary evaluation and critical review of a repeat abdominal computed tomography scan, a small nodular lesion was identified in the tail of the pancreas. The nodule was enucleated laparoscopically and the pathological examination revealed an insulinoma. In spite of the insulinoma resection, glycemic values were only partially restored, with residual nocturnal hypoglycemia. Administration of uncooked cornstarch (1.25 g/kg body weight) at bedtime was associated with significant improvement of interstitial glucose levels (p < 0.0001) and reduction of nocturnal hypoglycemia episodes (p = 0.0002). Conclusions: This report describes a rare coexistence of adult-onset nesidioblastosis and insulinoma, suggesting the existence of a wide and continuous spectrum of proliferative ß-cell changes. Moreover, we propose that uncooked cornstarch may offer an additional approach to alleviate the hypoglycemic episodes when surgery is impracticable/unaccepted.

Metabolic regulation of GLP-1 and PC1/3 in pancreatic α-cell line.

BACKGROUND AND AIMS: An intra-islet incretin system has been recently suggested to operate through modulation of the expression and activity of proconvertase 1/3 and 2 (PC1/3, PC2) in pancreatic alpha-cell accounting for local release of GLP-1. Little is known, whether this alpha-cell activity can be affected by the metabolic alterations occurring in type 2 diabetes, such as hyperglycemia, hyperlipidemia or hyperglucagonemia. MATERIALS AND METHODS: AlphaTC1/6 cells from a mice pancreatic cell line were incubated in the presence of two glucose (G) concentration (5.5 and 16.7 mM) for 16 h with or without free fatty acid, IL6 or glucagon. GLP-1 secretion was measured by ELISA and expression of PC1/3 and PC2 by RT-PCR and western blot; cell viability was determined by MTT method, Reactive Oxygen Species generation (ROS) by H2DCFDA fluorescence and apoptosis by Annexin staining and Propidium Iodine (PI) fluorescence. RESULTS: Upon 16.7G incubation, GLP-1 secretion (total and active) was significantly increased in parallel with a significant increment in PC1/3 expression, a slight increase in cell viability and ROS generation and by a decrement in PC2 expression with no change in cell apoptosis. When cells were incubated at 5.5mM glucose with FFA, also an increment in GLP-1 secretion and PC1/3 expression was observed together an increment in ROS generation, a decrement in cell viability, and a modest increment in apoptosis. When incubated with 16.7mM glucose with FFA, the increment in GLP-1 secretion was reduced to basal, accompanied by an increment in apoptosis and ROS generation. This was also observed with IL-6, but in this case, no modification in ROS generation or apoptosis was observed when compared to 16.7mM glucose. The presence of glucagon did not modify any of the parameters studied. CONCLUSION: These data suggest that under hyperglycemic, hyperlipidemia or inflammatory conditions, alpha cells can increase expression PC1/3 and activate GLP-1 secretion, which may contribute protecting both alpha and beta-cells from glucose and lipotoxicity, while this effect seems to be lost in the presence of both pathophysiological conditions.

Evidence for two distinct phenotypes of chronic kidney disease in individuals with type 1 diabetes mellitus.

AIMS/HYPOTHESIS: In a retrospective, observational, cross-sectional, single-centre study, we assessed the prevalence and correlates of different CKD phenotypes (with and without albuminuria) in a large cohort of patients of white ethnicity with type 1 diabetes. METHODS: From 2001 to 2009, 408 men and 369 women with type 1 diabetes (age 40.2 ± 11.7 years, diabetes duration 19.4 ± 12.2 years, HbA1c 7.83 ± 1.17% [62.0 ± 12.9 mmol/mol]) were recruited consecutively. Albumin-to-creatinine ratio (ACR) and eGFR (Modification of Diet in Renal Disease) were obtained for all individuals, together with CKD stage. Diabetic retinopathy and peripheral polyneuropathy were detected in 41.5% and 8.1%, respectively, and cardiovascular disease (CVD) occurred in 8.5%. Adjudications of CKD phenotype were made by blinded investigators. RESULTS: Normo- (ACR <3.4), micro- (ACR 3.4-34) or macroalbuminuria (ACR ≥34 mg/mmol) were present in 91.6%, 6.4% and 1.9% of individuals, respectively. eGFR categories 1 (≥90 ml min-1 [1.73 m]-2), 2 (60-89 ml min-1 [1.73 m]-2) and 3 (<60 ml min-1 [1.73 m]-2) were present in 57.3%, 39.0% and 3.7%, respectively. The majority of participants had no CKD (89.4%), while stages 1-2 and ≥3 CKD were detected in 6.8% and 3.7%, respectively. The albuminuric (Alb+) and non-albuminuric (Alb-) phenotypes were present in 12 (41.4%) and 17 (58.6%) individuals with stage ≥3 CKD, respectively. Individuals with an ACR <3.4 mg/mmol were subdivided into those with normal albuminuria (<1.1 mg/mmol; 77.2%) and mildly increased albuminuria (1.1-3.4 mg/mmol; 14.4%), and individuals with stage 2 CKD were subdivided into those with eGFR 75-89 ml min-1 [1.73 m]-2 and 60-74 ml min-1 [1.73 m]-2. ACR <3.4 mg/mmol (88.7%) and even <1.1 mg/mmol (70.4%) were common in individuals with eGFR 60-74 ml min-1 [1.73 m]-2. The prevalence of ACR <1.1 mg/mmol was lower but still significant (34.5%) in those with stage ≥3 CKD. In logistic regression analysis, stages 1-2 and ≥3 CKD were independently associated with age, HbA1c, γ-glutamyltransferase, fibrinogen, hypertension, but not with sex, BMI, smoking, HDL-cholesterol or triacylglycerol. Inclusion of advanced retinopathy removed HbA1c from the model. The CKD Alb+ phenotype correlated with diabetes duration, HbA1c, HDL-cholesterol, fibrinogen and hypertension, while the CKD Alb- phenotype was associated with age and hypertension, but not with diabetes duration, HbA1c and fibrinogen. CONCLUSIONS/INTERPRETATION: The Alb- CKD phenotype is present in a significant proportion of individuals with type 1 diabetes supporting the hypothesis of two distinct pathways (Alb+ and Alb-) of progression towards advanced kidney disease in type 1 diabetes. These are probably distinct pathways as suggested by different sets of covariates associated with the two CKD phenotypes.

Heterozygosity for the rs696217 SNP in the Preproghrelin Gene Predicts Weight Loss After Bariatric Surgery in Severely Obese Individuals.

BACKGROUND: Several patients encompass a scarce weight loss after Roux-en-Y gastric bypass (RYGB). As such event is not related to surgical complications, finding markers able to identify "well responders" and to predict weight loss outcome is clinically relevant. Ghrelin regulates appetite and energy balance. Common single nucleotide polymorphisms (SNPs) in its encoding genes have been associated with body weight regulation. Other peptides involved in satiety modulation, like the CD40/CD40L complex, are less explored. METHODS: One hundred, otherwise healthy, obese subjects (aged 45 ± 11 years, 65 females, BMI 48.0 ± 0.7 kg/m2) were sequentially enrolled in years 2014-2015. SNPs rs2241766 for adiponectin gene, rs490683 for ghrelin receptor, rs696217 and rs27647 for the preproghrelin/ghrelin gene, and rs1126535 for the CD40L gene were determined on DNA extracted from circulating lymphomonocytes. Patients were reevaluated at 6 (n = 100), 26 (n = 91), and 52 weeks (n = 79) after RYGB. RESULTS: Subjects carrying the rs696217 T allele encompassed a significantly greater reduction in BMI 52 weeks after surgery (GG vs GT 30.5 ± 1.1 vs 38.1 ± 2.1 %; p < 0.001). Carrying the rs1126535 C allele in the CD40L gene was associated with a significantly lower BMI reduction at week 52 (TT vs CT 33.2 ± 1.1 vs 28.1 ± 2.3 %, p = 0.049). rs490683 and rs27647 SNPs of ghrelin and rs2241766 for adiponectin gene did not show any difference between carriers and non-carriers of the mutant allele. CONCLUSION: Carrying a G to T substitution in rs696217 (preproghrelin gene) seems to mark a successful weight loss outcome; we also report for the first time that the rs1126535 C allele (CD40L gene) may predict a worse response to bariatric surgery.

New forms of insulin and insulin therapies for the treatment of type 2 diabetes.

Insulin is a common treatment option for many patients with type 2 diabetes, and is generally used late in the natural history of the disease. Its injectable delivery mode, propensity for weight gain and hypoglycaemia, and the paucity of trials assessing the risk-to-safety ratio of early insulin use are major shortcomings associated with its use in patients with type 2 diabetes. Development of new insulins-such as insulin analogues, including long-acting and short-acting insulins-now provide alternative treatment options to human insulin. These novel insulin formulations and innovative insulin delivery methods, such as oral or inhaled insulin, have been developed with the aim to reduce insulin-associated hypoglycaemia, lower intraindividual pharmacokinetic and pharmacodynamic variability, and improve imitation of physiological insulin release. Availability of newer glucose-lowering drugs (such as glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase-4 inhibitors, and sodium-glucose co-transporter-2 inhibitors) also offers the opportunity for combination treatment; the results of the first trials in this area of research suggest that such treatment might lead to use of reduced insulin doses, less weight gain, and fewer hypoglycaemic episodes than insulin treatment alone. These and future developments will hopefully offer better opportunities for individualisation of insulin treatment for patients with type 2 diabetes.

Optimal therapy of type 2 diabetes: a controversial challenge.

Type 2 diabetes mellitus (T2DM) is one of the most common chronic disorders in older adults and the number of elderly diabetic subjects is growing worldwide. Nonetheless, the diagnosis of T2DM in elderly population is often missed or delayed until an acute metabolic emergency occurs. Accumulating evidence suggests that both aging and environmental factors contribute to the high prevalence of diabetes in the elderly. Clinical management of T2DM in elderly subjects presents unique challenges because of the multifaceted geriatric scenario. Diabetes significantly lowers the chances of "successful" aging, notably it increases functional limitations and impairs quality of life. In this regard, older diabetic patients have a high burden of comorbidities, diabetes-related complications, physical disability, cognitive impairment and malnutrition, and they are more susceptible to the complications of dysglycemia and polypharmacy. Several national and international organizations have delivered guidelines to implement optimal therapy in older diabetic patients based on individualized treatment goals. This means appreciation of the heterogeneity of the disease as generated by life expectancy, functional reserve, social support, as well as personal preference. This paper will review current treatments for achieving glycemic targets in elderly diabetic patients, and discuss the potential role of emerging treatments in this patient population.

Adipocytokines mark insulin sensitivity in euthyroid Hashimoto's patients.

The relationship between inflammation, Hashimoto's thyroiditis (HT) and insulin resistance is still controversial. In this regard, a pretty complete evaluation of adipocytokines levels in patients with HT has not been performed so far. We assessed retinol binding protein-4 (RBP4), adipocyte-fatty acid binding protein (A-FABP), neutrophil gelatinase-associated lipocalin (NGAL) and tumor necrosis factor-α (TNFα) levels in 93 euthyroid HT patients and 51 healthy controls (CTL), also evaluating the possible correlation between adipocytokines levels and markers of insulin resistance. No significant differences between HT patients and CTL in fasting plasma glucose and insulin levels, and HOMA index were observed. HT patients had significantly higher RBP4, NGAL and A-FABP levels than CTL, while TNFα levels did not differ between the two groups. In HT patients, RBP4 was significantly related with fT3 and fT4 levels, while A-FABP with fT4 only. Moreover, in HT patients, either RBP4 or A-FABP was directly associated with plasma insulin and HOMA index. Circulating levels of these adipocytokines were not influenced by the presence of antithyroid peroxidase or antithyroglobulin autoantibodies or only one of them, neither by autoantibodies titer. In conclusion, euthyroid HT patients are characterized by a peculiar inflammatory response of the adipose tissue, apparently related to an early reduction in insulin sensitivity and to serum thyroid hormone levels, although within the normal range. These results suggest that HT patients with high RBP4 and A-FABP levels might deserve a particular attention, being potentially more exposed to develop insulin resistance and increased cardiovascular risk.

The effect of Ginkgo biloba extract on genotoxic damage in patients with differentiated thyroid carcinoma receiving thyroid remnant ablation with iodine-131.

BACKGROUND: Radioiodine ((131)I) therapy is usually performed in patients with differentiated thyroid cancer (DTC). Although (131)I is generally considered safe, genotoxic damage has been demonstrated both in vivo and in vitro. The aim of the current study was to evaluate the effect of Ginkgo biloba extract (GBE) on the time-course of appearance, after (131)I therapy for DTC, of plasma factors with chromosome-damaging properties (so-called "clastogenic" factors [CFs]) and of micronuclei (MN) in lymphocytes. METHODS: Twenty-three patients (median age 42 years, range 18-73) with DTC receiving (131)I activity (3.7 GBq) for thyroid remnant ablation were randomly assigned to receive GBE (120 mg/day for one month; n=10) or placebo (n=13) in a double-blind manner. Blood samples were taken at various intervals (from baseline to 90 days) after (131)I therapy. The frequency of MN in blood lymphocytes was determined, and CFs were assayed in plasma by a method that used MN increase in lymphocytes from an healthy donor as the endpoint of the assay. RESULTS: MN in blood lymphocytes increased significantly after (131)I treatment in the placebo group, peaking at the 7th day (p=0.002) and slowly declining thereafter. In contrast, in similarly treated patients who were also treated with GBE both before and after (131)I treatment, a significant increase of blood lymphocyte MN level was not observed. In addition, only the placebo group showed a significant, progressive increase in CFs activity. This peaked at the 14th day (p=0.003 vs. baseline) and was still noted for the last plasma sample. The differences in the change in lymphocyte MN and CFs activity between the placebo and GBE-treated groups were significant (p<0.01 and p<0.05, respectively). Thyroid function tests, including serum thyroglobulin (Tg) and anti-Tg antibody levels, were never significantly different. CONCLUSIONS: GBE may protect from possible oxidative and genotoxic damage associated with (131)I treatment in patients requiring (131)I therapy for thyroid cancer, without affecting the clinical outcome. Further studies with larger cohorts of patients are needed to confirm this report and verify the beneficial effect of GBE in patients requiring (131)I therapy, particularly for those in whom repeated treatments and high activities of (131)I are required.

Identification and optimal postsurgical follow-up of patients with very low-risk papillary thyroid microcarcinomas.

CONTEXT: Most papillary thyroid microcarcinomas (PTMCs; ≤ 1 cm diameter) are indolent low-risk tumors, but some cases behave more aggressively. Controversies have thus arisen over the optimum postoperative surveillance of PTMC patients. OBJECTIVES: We tested the hypothesis that clinical criteria could be used to identify PTMC patients with very low mortality/recurrence risks and attempted to define the best strategy for their management and long-term surveillance. DESIGN: We retrospectively analyzed data from 312 consecutively diagnosed PTMC patients with T1N0M0 stage disease, no family history of thyroid cancer, no history of head-neck irradiation, unifocal PTMC, no extracapsular involvement, and classic papillary histotypes. Additional inclusion criteria were complete follow-up data from surgery to at least 5 yr after diagnosis. All 312 had undergone (near) total thyroidectomy [with radioactive iodine (RAI) remnant ablation in 137 (44%) - RAI group] and were followed up yearly with cervical ultrasonography and serum thyroglobulin, TSH, and thyroglobulin antibody assays. RESULTS: During follow-up (5-23 yr, median 6.7 yr), there were no deaths due to thyroid cancer or reoperations. The first (6-12 months after surgery) and last postoperative cervical sonograms were negative in all cases. Final serum thyroglobulin levels were undetectable (<1 ng/ml) in all RAI patients and almost all (93%) of non-RAI patients. CONCLUSION: Accurate risk stratification can allow safe follow-up of most PTMC patients with a less intensive, more cost-effective protocol. Cervical ultrasonography is the mainstay of this protocol, and negative findings at the first postoperative examination are highly predictive of positive outcomes.

Insulinoma presenting as idiopathic hypersomnia.

We report the case of a 32-year-old woman with a history of increased sleep need and difficulty waking up; the diagnosis of idiopathic hypersomnia was hypothesized. During ambulatory polysomnography (PSG), the patient presented an episode characterized by loss of consciousness and jerking of the four limbs. A video-PSG monitoring was performed and the patient showed unresponsiveness and drowsiness at 7 a.m. During the episode, EEG showed theta-delta diffuse activity, and blood glucose level was 32 mg dl(-1). The diagnosis of insulinoma was then assumed; CT scan showed a hypodense mass into the pancreatic tail, and a partial pancreasectomy was performed. The described symptoms disappeared, and 5 years later the findings of a complete clinical and neurophysiological examination were negative. The clinical picture of insulinoma presenting with paroxysmal disorders has been previously described; however, whereas hypersomnia is uncommon, in the current case it represents the main symptom. Clinicians should keep in mind that neuroglycopenia should be considered in the differential diagnosis of patients with hypersomnia, particularly if the clinical scenario does not conform to standard criteria.

Non-thyroidal illness syndrome and short-term survival in a hospitalised older population.

BACKGROUND: non-thyroidal illness syndrome (NTIS) has been associated with an adverse clinical outcome. OBJECTIVE: to evaluate the prevalence of NTIS, its impact on patients' survival and the possible pathogenic role of systemic inflammation. DESIGN: observational cross-sectional analysis. PARTICIPANTS AND SETTING: three hundred and one acutely ill older patients (156 women; median age 81 years, range 65-101) consecutively admitted to a primary care unit. METHODS: serum FT(3), FT(4) and thyrotropin levels as well as acute inflammation indexes were evaluated. RESULTS: the NTIS prevalence (specifically low T3 syndrome) was 31.9%. A significant association was found between NTIS and acute renal failure (P = 0.006), New York Heart Association classification (NYHA) IV heart failure (P = 0.003) and metastasised cancer disease (P = 0.0002). Serum FT(3) values correlated inversely with serum C-reactive protein (P < 0.0001), lactate dehydrogenase (P = 0.0004), fibrinogen (P = 0.03) and erythrocyte sedimentation rate (P < 0.0001) values, and progressively decreased with increasing tertiles of age (P = 0.0004). The mortality rate was significantly higher (P = 0.0002) among patients with low T3 syndrome, which emerged as the sole predictive factor of death (odds ratio 4.3; 95% confidence interval 1.7-10.5). CONCLUSIONS: low T3 syndrome is very common in the hospitalised older population, emerging as the most sensitive independent predictor of short-term survival. Serum FT(3) determination should be included in the assessment of short-term prognosis of acutely ill older patients.

Chromosome translocation frequency after radioiodine thyroid remnant ablation: a comparison between recombinant human thyrotropin stimulation and prolonged levothyroxine withdrawal.

BACKGROUND: Thyroid remnant ablation of differentiated thyroid carcinoma (DTC) patients is traditionally performed after levothyroxine withdrawal. Recombinant human TSH (rhTSH) administration increases serum TSH levels without inducing hypothyroidism. AIM: The aim of the study was to investigate the frequency of chromosome translocations in DTC patients after the first (131)I therapeutic dose and compare the frequency of translocations between DTC patients off levothyroxine and those receiving rhTSH. PATIENTS AND METHODS: A total of 20 DTC patients were randomly assigned to levothyroxine withdrawal [(30 d) group A; n=10, nine women; mean age 48.5+/- 19.2 yr] or rhTSH injections [(0.9 mg im per 2 consecutive days) group B; n=10, eight women; mean age 50.4+/- 18.8 yr] before undergoing (131)I activity (3.7 GBq). The frequency of translocations in peripheral lymphocytes was analyzed by tricolor fluorescence in situ hybridization with whole-chromosome-specific probes for chromosomes 1, 4, and 8. Lymphocytes were stained routinely (about 500 each time). RESULTS: The two groups showed similar baseline translocation frequency. After (131)I administration, the total chromosomal translocation rate was significantly lower in group B than group A (P = 0.02). The frequency of translocations increased significantly in group A only (P = 0.01 vs. baseline). Rearrangement specifically involved chromosomes 4 and 8 (P = 0.02 vs. baseline). CONCLUSIONS: Our preliminary data show that in hypothyroid status (131)I ablation therapy induces a higher translocation rate, especially in chromosomes 4 and 8. This finding, in agreement with previous dosimetric reports, suggests that whereas inducing a low extrathyroid exposure, rhTSH reduces the potential risk of chromosomal aberration associated with blood irradiation.

Effect of type I interferon(s) on cell viability and apoptosis in primary human thyrocyte cultures.

BACKGROUND: Interferon (IFN) therapy may induce a generalized activation of the immune system, hence triggering or exacerbating autoimmune disease. Apoptosis contributes to the development of hypothyroidism in autoimmune thyroiditis. IFN can affect all phases of the cell cycle and may induce apoptosis in several cell lines from varied histologies. To date, no data exist on the possible effect of type I IFN(s) on FAS/FASL system and cell apoptosis of human thyroid follicles. Therefore, we evaluated the effect of both IFN-alpha and -beta on apoptosis in primary human thyrocyte cultures and the potential role of the FAS/FASL pathway. METHODS: Thyrocytes were cultured in monolayers and FAS, FASL, and Bcl-2 mRNA expression was determined by reverse transcriptase polymerase chain reaction after exposure to 10 mIU/mL bovine thyroid-stimulating hormone alone or in combination with increasing doses of IFN-alpha or -beta for 24, 48, and 72 hours. The percentage of apoptotic hypodiploid cells was evaluated by flow cytometry. RESULTS: Thyroid-stimulating hormone significantly decreased FAS and increased Bcl-2 mRNA expression while reducing the percentage of hypodiploid cells. The concomitant addition of either IFN-alpha or -beta reduced cell viability and increased the number of hypodiloid cells, but only IFN-beta modulated the expression of FAS and Bcl-2 mRNA expression in a proapoptotic sense. CONCLUSIONS: Both type I IFN(s) increase apoptosis in primary thyrocyte cultures, but only IFN-beta modulates FAS and Bcl-2 gene expression toward a proapoptotic pathway. Because apoptosis plays an important role in thyroid homeostasis and disease, this mechanism may contribute to the development and progression of type I IFN(s) therapy-associated thyroid disease.

1513A>C polymorphism in the P2X7 receptor gene in patients with papillary thyroid cancer: correlation with histological variants and clinical parameters.

INTRODUCTION: The modulation of the purinergic receptor P2X7 may be implicated in human carcinogenesis. The 1513A>C and 489C>T polymorphisms of P2X7R gene induce loss of function and gain of function, respectively. AIM: The aim of the study was to assess the frequency of both 1513A>C and 489C>T polymorphisms in patients with papillary thyroid carcinoma (PTC) and to evaluate the possible association with clinical and histological features. PATIENTS AND METHODS: P2X7R analysis was performed in lymphocytes from 121 PTC patients (100 women, 21 men; aged 43.4 +/- 13.6 yr), 100 matched healthy subjects, and 80 patients with nodular goiter. RESULTS: The minor allele frequency for 1513A>C polymorphism in PTC patients with the classical variant was similar to controls (0.21 and 0.20, respectively), whereas it resulted in a significant increase in patients with the follicular variant (0.36; P = 0.01 vs. classical variant, and P = 0.005 vs. controls). In detail, 13.6% of patients with PTC follicular variant were homozygous for the 1513C allele, compared to 2.6% of patients with the classical variant and 2% of controls. Moreover, a positive relationship between 1513A>C polymorphism and either cancer diameter (Rho = 0.22; P = 0.02) or TNM stage (Rho = 0.38; P < 0.001) was found. No significant difference in the genotype frequency of 489C>T polymorphism between PTC patients and healthy controls was observed (0.42 and 0.47, respectively). CONCLUSIONS: Our data show, for the first time, a strong association between 1513A>C polymorphism of P2X7R gene and the follicular variant of PTC. Further studies are needed to confirm the possible role of this polymorphism as a novel clinical marker of PTC follicular variant and its usefulness in selecting patients with different clinical outcome.

Inducible nitric oxide synthase is involved in endothelial dysfunction of mesenteric small arteries from hypothyroid rats.

The time-dependent effects of mild hypothyroidism on endothelial function were assessed in rat mesenteric arteries. Male Wistar rats were treated with methimazole (MMI; 0.003%) or placebo up to 16 wk. Endothelial function of mesenteric small arteries was assessed by pressurized myograph. MMI-treated animals displayed a decrease in serum thyroid hormones, an increment of plasma TSH and inflammatory cytokines, and a blunted vascular relaxation to acetylcholine, as compared with controls. Endothelial dysfunction resulted from a reduced nitric oxide (NO) availability caused by oxidative excess. Vascular-inducible NO synthase (iNOS) expression was up-regulated. S-methylisothiourea (an iNOS inhibitor) normalized endothelium-dependent relaxations and restored NO availability in arteries from 8-wk MMI-animals and partly ameliorated these alterations in 16-wk MMI rats. Similar results were obtained when MMI-induced hypothyroidism was prevented by T(4) replacement. Among controls, an impaired NO availability, secondary to oxidative excess, occurred at 16 wk, and it was less pronounced than in age-matched MMI animals. Both endothelial dysfunction and oxidant excess secondary to aging were prevented by apocynin (nicotinamide adenine dinucleotide phosphate oxidase inhibitor). Mesenteric superoxide production was reduced by S-methylisothiourea and T(4) replacement in MMI animals and abolished by apocynin in controls (dihydroethidium staining). MMI-induced mild hypothyroidism is associated with endothelial dysfunction caused by a reduced NO availability, secondary to oxidative excess. It is suggested that in this animal model, characterized by TSH elevation and low-grade inflammation, an increased expression and function of iNOS, resulting in superoxide generation, accounts for an impaired NO availability.

Increased P2X7 receptor expression and function in thyroid papillary cancer: a new potential marker of the disease?

Nucleotides are increasingly recognized as nonredundant extracellular signals for chemotaxis, cell growth, and cytokine release. Effects of extracellular nucleotides are mediated by P2 receptors, among which the P2X(7) subtype is attracting increasing attention for its involvement in apoptosis, cell growth, and cytokine release. Recent studies showed that P2X(7) is overexpressed in chronic lymphocytic leukemia and breast and prostate cancer. The aim of the present study was to better understand the clinical significance of P2X(7) receptor expression in normal and cancer human thyroid tissues. P2X(7) receptor message and protein expression and functional activity were tested in two cell lines (FB1 and FB2) established from either anaplastic or papillary primary thyroid cancer and in several histological samples of human papillary cancer. We show here that human thyroid papillary carcinoma, whether of the classical or follicular variant, expresses the P2X(7) receptor (P2X(7)R) to a much higher level than normal thyroid tissue. The P2X(7)R was similarly up-regulated in FB1 and FB2 cell lines. In contrast to normal thyroid cells, both cell lines responded to extracellular nucleotide stimulation with a large increase in intracellular Ca(2+) and secretion of IL-6. Ca(2+) increase was attenuated and release of IL-6 was fully blocked by P2X(7)R inhibitors. Finally, the thyroid carcinoma cell lines had at least a 3-fold higher intracellular ATP concentration and maintained at least a 3-fold higher extracellular ATP level, compared with control cells. These data suggest that an enhanced P2X(7)R function might be a feature of human thyroid cancer.