Strain-Dependent Morphology of Reactive Astrocytes in Human- and Animal-Vole-Adapted Prions

Reactive astrogliosis is one of the pathological hallmarks of prion diseases. Recent studies highlighted the influence of several factors on the astrocyte phenotype in prion diseases, including the brain region involved, the genotype backgrounds of the host, and the prion strain. Elucidating the influence of prion strains on the astrocyte phenotype may provide crucial insights for developing therapeutic strategies. Here, we investigated the relationship between prion strains and astrocyte phenotype in six human- and animal-vole-adapted strains characterized by distinctive neuropathological features. In particular, we compared astrocyte morphology and astrocyte-associated PrP^Sc deposition among strains in the same brain region, the mediodorsal thalamic nucleus (MDTN). Astrogliosis was detected to some extent in the MDTN of all analyzed voles. However, we observed variability in the morphological appearance of astrocytes depending on the strain. Astrocytes displayed variability in thickness and length of cellular processes and cellular body size, suggesting strain-specific phenotypes of reactive astrocytes. Remarkably, four out of six strains displayed astrocyte-associated PrP^Sc deposition, which correlated with the size of astrocytes. Overall, these data show that the heterogeneous reactivity of astrocytes in prion diseases depends at least in part on the infecting prion strains and their specific interaction with astrocytes.

A single amino acid residue in bank vole prion protein drives permissiveness to Nor98/atypical scrapie and the emergence of multiple strain variants

Prions are infectious agents that replicate through the autocatalytic misfolding of the cellular prion protein (PrP^C) into infectious aggregates (PrP^Sc) causing fatal neurodegenerative diseases in humans and animals. Prions exist as strains, which are encoded by conformational variants of PrP^Sc. The transmissibility of prions depends on the PrP^C sequence of the recipient host and on the incoming prion strain, so that some animal prion strains are more contagious than others or are transmissible to new species, including humans. Nor98/atypical scrapie (AS) is a prion disease of sheep and goats reported in several countries worldwide. At variance with classical scrapie (CS), AS is considered poorly contagious and is supposed to be spontaneous in origin. The zoonotic potential of AS, its strain variability and the relationships with the more contagious CS strains remain largely unknown. We characterized AS isolates from sheep and goats by transmission in ovinised transgenic mice (tg338) and in two genetic lines of bank voles, carrying either methionine (BvM) or isoleucine (BvI) at PrP residue 109. All AS isolates induced the same pathological phenotype in tg338 mice, thus proving that they encoded the same strain, irrespective of their geographical origin or source species. In bank voles, we found that the M109I polymorphism dictates the susceptibility to AS. BvI were susceptible and faithfully reproduced the AS strain, while the transmission in BvM was highly inefficient and was characterized by a conformational change towards a CS-like prion strain. Sub-passaging experiments revealed that the main strain component of AS is accompanied by minor CS-like strain components, which can be positively selected during replication in both AS-resistant or AS-susceptible animals. These findings add new clues for a better comprehension of strain selection dynamics in prion infections and have wider implications for understanding the origin of contagious prion strains, such as CS.

Prions are transmissible agents responsible for fatal neurodegenerative diseases in humans and animals. Prions exist as strains, exhibiting distinct disease phenotypes and transmission properties. Some prion diseases occur sporadically with a supposedly spontaneous origin, while others are contagious and give rise to epidemics, mainly in animals. We investigated the strain properties of Nor98/atypical scrapie (AS), a sporadic prion disease of small ruminants. We found that AS was faithfully reproduced not only in a homologous context, i.e. ovinised transgenic mice, but also in an unrelated animal species, the bank vole. A natural polymorphism of the bank vole prion protein, coding for methionine (BvM) or for isoleucine (BvI) at codon 109, dictated the susceptibility of voles to AS, with BvI being highly susceptible to AS and BvM rather resistant. Most importantly, the M109I polymorphism mediated the emergence of AS-derived mutant prion strains resembling classical scrapie (CS), a contagious prion disease. Finally, by sub-passages in bank voles, we found that the main strain component of AS is accompanied by minor CS-like strain components, which can be positively selected during replication in both AS-resistant or AS-susceptible vole lines. These findings allow a better understanding of strain selection dynamics and suggest a link between sporadic and contagious prion diseases.

Studies in bank voles reveal strain differences between chronic wasting disease prions from Norway and North America

Chronic wasting disease (CWD) is a relentless epidemic disorder caused by infectious prions that threatens the survival of cervid populations and raises increasing public health concerns in North America. In Europe, CWD was detected for the first time in wild Norwegian reindeer (Rangifer tarandus) and moose (Alces alces) in 2016. In this study, we aimed at comparing the strain properties of CWD prions derived from different cervid species in Norway and North America. Using a classical strain typing approach involving transmission and adaptation to bank voles (Myodes glareolus), we found that prions causing CWD in Norway induced incubation times, neuropathology, regional deposition of misfolded prion protein aggregates in the brain, and size of their protease-resistant core, different from those that characterize North American CWD. These findings show that CWD prion strains affecting Norwegian cervids are distinct from those found in North America, implying that the highly contagious North American CWD prions are not the proximate cause of the newly discovered Norwegian CWD cases. In addition, Norwegian CWD isolates showed an unexpected strain variability, with reindeer and moose being caused by different CWD strains. Our findings shed light on the origin of emergent European CWD, have significant implications for understanding the nature and the ecology of CWD in Europe, and highlight the need to assess the zoonotic potential of the new CWD strains detected in Europe.

Isolation of infectious, non-fibrillar and oligomeric prions from a genetic prion disease

Prions are transmissible agents causing lethal neurodegenerative diseases that are composed of aggregates of misfolded cellular prion protein (PrPSc). Despite non-fibrillar oligomers having been proposed as the most infectious prion particles, prions purified from diseased brains usually consist of large and fibrillar PrPSc aggregates, whose protease-resistant core (PrPres) encompasses the whole C-terminus of PrP. In contrast, PrPSc from Gerstmann-Sträussler-Scheinker disease associated with alanine to valine substitution at position 117 (GSS-A117V) is characterized by a small protease-resistant core, which is devoid of the C-terminus. We thus aimed to investigate the role of this unusual PrPSc in terms of infectivity, strain characteristics, and structural features. We found, by titration in bank voles, that the infectivity of GSS-A117V is extremely high (109.3 ID50 U/g) and is resistant to treatment with proteinase K (109.0 ID50 U/g). We then purified the proteinase K-resistant GSS-A117V prions and determined the amount of infectivity and PrPres in the different fractions, alongside the morphological characteristics of purified PrPres aggregates by electron microscopy. Purified pellet fractions from GSS-A117V contained the expected N- and C-terminally cleaved 7 kDa PrPres, although the yield of PrPres was low. We found that this low yield depended on the low density/small size of GSS-A117V PrPres, as it was mainly retained in the last supernatant fraction. All fractions were highly infectious, thus confirming the infectious nature of the 7 kDa PrPres, with infectivity levels that directly correlated with the PrPres amount detected. Finally, electron microscopy analysis of these fractions showed no presence of amyloid fibrils, but only very small and indistinct, non-fibrillar PrPresparticles were detected and confirmed to contain PrP via immunogold labelling. Our study demonstrates that purified aggregates of 7 kDa PrPres, spanning residues ∼90-150, are highly infectious oligomers that encode the biochemical and biological strain features of the original sample. Overall, the autocatalytic behaviour of the prion oligomers reveals their role in the propagation of neurodegeneration in patients with Gerstmann-Sträussler-Scheinker disease and implies that the C-terminus of PrPSc is dispensable for infectivity and strain features for this prion strain, uncovering the central PrP domain as the minimal molecular component able to encode infectious prions. These findings are consistent with the hypothesis that non-fibrillar prion particles are highly efficient propagators of disease and provide new molecular and morphological constraints on the structure of infectious prions.

Glucose lowering strategies and cardiovascular disease in type 2 diabetes - teachings from the TOSCA.IT study

TOSCA.IT is an institutional, non-industry-supported, head-to-head study comparing long term cardiovascular effects, efficacy and safety of two antidiabetes drugs (pioglitazone vs sulphonylureas) used in combination with metformin in patients with type 2 diabetes mellitus. The study results show that in the absence of clinically evident cardiovascular disease both treatment strategies represent suitable alternatives; however, in consideration of the greater durability of the metabolic effects, the lower risk of hypoglycemia and the potential benefit on atherosclerotic cardiovascular disease, the combination of metformin and pioglitazone may be considered as the preferential therapeutic option. In this review the study is critically evaluated against the background of the evidence accumulated over the last decade on the impact of different glucose lowering drugs on cardiovascular events in people with type 2 diabetes.

Prion Disease in Dromedary Camels, Algeria

Prions cause fatal and transmissible neurodegenerative diseases, including Creutzfeldt-Jakob disease in humans, scrapie in small ruminants, and bovine spongiform encephalopathy (BSE). After the BSE epidemic, and the associated human infections, began in 1996 in the United Kingdom, general concerns have been raised about animal prions. We detected a prion disease in dromedary camels (Camelus dromedarius) in Algeria. Symptoms suggesting prion disease occurred in 3.1% of dromedaries brought for slaughter to the Ouargla abattoir in 2015–2016. We confirmed diagnosis by detecting pathognomonic neurodegeneration and disease-specific prion protein (PrP^Sc) in brain tissues from 3 symptomatic animals. Prion detection in lymphoid tissues is suggestive of the infectious nature of the disease. PrP^Sc biochemical characterization showed differences with BSE and scrapie. Our identification of this prion disease in a geographically widespread livestock species requires urgent enforcement of surveillance and assessment of the potential risks to human and animal health.

Metabolic control and complications in Italian people with diabetes treated with continuous subcutaneous insulin infusion

BACKGROUND AND AIM

The objective of this cross-sectional study was to evaluate the degree of glycaemic control and the frequency of diabetic complications in Italian people with diabetes who were treated with continuous subcutaneous insulin infusion (CSII).

METHODS AND RESULTS

Questionnaires investigating the organisation of diabetes care centres, individuals' clinical and metabolic features and pump technology and its management were sent to adult and paediatric diabetes centres that use CSII for treatment in Italy. Information on standard clinical variables, demographic data and acute and chronic diabetic complications was derived from local clinical management systems. The sample consisted of 6623 people with diabetes, which was obtained from 93 centres. Of them, 98.8% had type 1 diabetes mellitus, 57.2% were female, 64% used a conventional insulin pump and 36% used a sensor-augmented insulin pump. The median glycated haemoglobin (HbA_1c) level was 60 mmol/mol (7.6%). The HbA_1c target (i.e. <58 mmol/mol for age <18 years and <53 mmol/mol for age >18 years) was achieved in 43.4% of paediatric and 23% of adult participants. Factors such as advanced pump functions, higher rate of sensor use, pregnancy in the year before the study and longer duration of diabetes were associated with lower HbA_1c levels. The most common chronic complications occurring in diabetes were retinopathy, microalbuminuria and hypertension. In the year before the study, 5% of participants reported ≥1 episode of severe hypoglycaemic (SH) episodes (SH) and 2.6% reported ≥1 episode of ketoacidosis.

CONCLUSIONS

Advanced personal skills and use of sensor-based pump are associated with better metabolic control outcomes in Italian people with diabetes who were treated with CSII. The reduction in SH episodes confirms the positive effect of CSII on hypoglycaemia.

CLINICAL TRIAL REGISTRATION NUMBER

NCT 02620917 (ClinicalTrials.gov).

Intensive dietary intervention promoting the Mediterranean diet in people with high cardiometabolic risk: a non-randomized study

AIMS

Mediterranean diet (MD) is acknowledged to exert a number of beneficial health effects. We assessed the efficacy and the durability of a 3-month intensive dietary intervention aimed at implementing the MD on body weight and cardiometabolic risk factors in subjects at high risk.

METHODS

One hundred and sixteen subjects participated in the study (71 assigned to the intensive intervention and 45 to the conventional intervention). The intensive intervention consisted of 12 weekly group educational meetings and a free-of-charge supply of meals prepared according to the MD model. The conventional intervention consisted of an individual education session along with monthly reinforcements of nutritional messages by the general practitioner. All participants were followed up for 9 months.

RESULTS

The two groups had similar pre-intervention characteristics. After the intervention, mean body weight decreased significantly in both groups (p < 0.001). However, the intervention group lost more weight (6.8 ± 4.0 vs. 0.7 ± 1.3, p < 0.0001) and showed a greater reduction in plasma glucose, triglycerides, blood pressure and an increase in HDL cholesterol than the control group (p < 0.01-p < 0.002). In the subgroup of participants with type 2 diabetes, there was a significant reduction in HbA1c level following the intensive (p < 0.0001) but not the conventional intervention. At follow-up, weight loss still persisted in the intervention group (p < 0.0001), while it was lost in the control group. Both interventions significantly reduced blood pressure in the long term (p < 0.001). A significant reduction in daily total energy intake was observed in both groups with a greater reduction in saturated fat and a higher increase in fibre intake in the intervention than in the control group (p < 0.009 and p < 0.001, respectively).

CONCLUSIONS

A 3-month intensive dietary intervention inspired to the traditional MD produced greater and more durable weight loss and improvement in cardiometabolic risk profile than the conventional intervention.

A systematic review on the relations between pasta consumption and cardio-metabolic risk factors

AIMS

The traditional Italian dish pasta is a major food source of starch with low glycemic index (GI) and an important low-GI component of the Mediterranean diet. This systematic review aimed at assessing comprehensively and in-depth the potential benefit of pasta on cardio-metabolic disease risk factors.

DATA SYNTHESIS

Following a standard protocol, we conducted a systematic literature search of PubMed, CINAHL, and Cochrane Central Register of Controlled Trials for prospective cohort studies and randomized controlled dietary intervention trials that examined pasta and pasta-related fiber and grain intake in relation to cardio-metabolic risk factors of interest. Studies comparing postprandial glucose response to pasta with that to bread or potato were quantitatively summarized using meta-analysis of standardized mean difference. Evidence from studies with pasta as part of low-GI dietary intervention and studies investigating different types of pasta were qualitatively summarized.

CONCLUSIONS

Pasta meals have significantly lower postprandial glucose response than bread or potato meals, but evidence was lacking in terms of how the intake of pasta can influence cardio-metabolic disease risk. More long-term randomized controlled trials are needed where investigators directly contrast the cardio-metabolic effects of pasta and bread or potato. Long-term prospective cohort studies with required data available should also be analyzed regarding the effect of pasta intake on disease endpoints.

Diabetes remission after bariatric surgery is characterized by high glycemic variability and high oxidative stress

BACKGROUND AND AIM

To evaluate glycemic variability (GV) and oxidative stress in patients who achieved type 2 diabetes (T2DM) remission after bariatric surgery (BS).

METHODS AND RESULTS

Twenty-two patients (M/F10/12, age 50 ± 9 years, BMI 31 ± 6 kg/m²) who were in remission of T2DM (T2DM remitters) after BS since at least 1 year and 22 age-, sex- and BMI-matched control subjects were studied. Of the BS group, eleven subjects had undergone Roux-en-Y gastric bypass (RYGB) and eleven subjects sleeve gastrectomy (SG). Oral glucose tolerance test (OGTT), 7 days-continuous glucose monitoring, 24-h urinary excretion of 8-isoprostaglandin F2α (8-isoPGF2α) and dietary intake evaluation were performed. According to general linear model for repeated measures, glucose and insulin response during OGTT were significantly different in T2DM remitter than in control subjects (p < 0.001, for both). All measures of GV (standard deviation, coefficient of variation and mean amplitude of glucose excursions) were significantly higher in T2DM remitters than in controls, (p < 0.001 for all). These indexes were higher among RYGB than SG patients (p < 0.05). The time spent out of the 60-160 mg/dl range was significantly longer in T2DM remitters undergoing RYGB than in controls (p < 0.02). Mean 24-h urinary 8-isoPGF2α excretion was significantly higher in T2DM remitters than that of control subjects (p = 0.04). All GV indexes were directly correlated with blood glucose levels at 30 and 60 min during OGTT (p < 0.05-0.001).

CONCLUSION

Remission of T2DM after BS is characterized by high GV and high oxidative stress in the face of fasting blood glucose and HbA1c within the normal range.

Fructose intervention for 12 weeks does not impair glycemic control or incretin hormone responses during oral glucose or mixed meal tests in obese men

BACKGROUND AND AIMS

Incretin hormones glucagon-like peptide (GLP)-1 and glucose-dependent insulinotropic polypeptide (GIP) are affected early on in the pathogenesis of metabolic syndrome and type 2 diabetes. Epidemiologic studies consistently link high fructose consumption to insulin resistance but whether fructose consumption impairs the incretin response remains unknown.

METHODS AND RESULTS

As many as 66 obese (BMI 26-40 kg/m²) male subjects consumed fructose-sweetened beverages containing 75 g fructose/day for 12 weeks while continuing their usual lifestyle. Glucose, insulin, GLP-1 and GIP were measured during oral glucose tolerance test (OGTT) and triglycerides (TG), GLP-1, GIP and PYY during a mixed meal test before and after fructose intervention. Fructose intervention did not worsen glucose and insulin responses during OGTT, and GLP-1 and GIP responses during OGTT and fat-rich meal were unchanged. Postprandial TG response increased significantly, p = 0.004, and we observed small but significant increases in weight and liver fat content, but not in visceral or subcutaneous fat depots. However, even the subgroups who gained weight or liver fat during fructose intervention did not worsen their glucose, insulin, GLP-1 or PYY responses. A minor increase in GIP response during OGTT occurred in subjects who gained liver fat (p = 0.049).

CONCLUSION

In obese males with features of metabolic syndrome, 12 weeks fructose intervention 75 g/day did not change glucose, insulin, GLP-1 or GIP responses during OGTT or GLP-1, GIP or PYY responses during a mixed meal. Therefore, fructose intake, even accompanied with mild weight gain, increases in liver fat and worsening of postprandial TG profile, does not impair glucose tolerance or gut incretin response to oral glucose or mixed meal challenge.

Food group consumption in an Italian population using the updated food classification system FoodEx2: Results from the Italian Nutrition & HEalth Survey (INHES) study

BACKGROUND AND AIM

Dietary habits evolve over time, being influenced by many factors and complex interactions. This work aimed at evaluating the updated information on food group consumption in Italy.

METHODS AND RESULTS

A total of 8944 (4768 women and 4176 men) participants aged >18 years from all over Italy recruited in 2010-13 (Italian Nutrition & HEalth Survey, INHES) was analyzed. The recruitment was performed using computer-assisted-telephone-interviewing and one-day 24-h dietary recall retrieved from all participants. The updated, second version, of FoodEx2 food classification system was applied to extract data on food group consumption. The participation rate was 53%; 6.2% of the participants declared to follow a special diet, the most prevalent being hypo-caloric diets (55.7% of special diets). Men compared to women presented significantly higher intakes of "grains and grain-based products", "meat and meat products", "animal and vegetable fats and oils and primary derivatives" and "alcoholic beverages" (P for all<0.001); moreover, men had lower intakes of "milk and dairy products", "water and water-based beverages" and "products for non-standard diets, food imitates and food supplements" (P for all<0.001). Differences in food group intake among age groups, geographical regions and educational level groups were also identified (P for all<0.05).

CONCLUSIONS

Data on the consumption of more than 70 food groups and sub-groups were illustrated in different strata. The present analysis could be considered as an updated source of information for future nutrition research in Italy and in the EU.

Additional predictive value of nutritional status in the prognostic assessment of heart failure patients

BACKGROUND AND AIMS

Nutritional status (NS) is not routinely assessed in HF. We sought to evaluate whether NS may be additive to a comprehensive pre-discharge evaluation based on a clinical score that includes BMI (MAGGIC) and on an index of functional capacity (six minute walking test, 6mWT) in HF patients.

METHODS AND RESULTS

The CONUT (Controlling Nutritional Status) score (including serum albumin level, total cholesterol and lymphocyte count) was computed in 466 consecutive patients (mean age 61 ± 11 years, NYHA class 2.6 ± 0.6, LVEF 34 ± 11%, BMI 27.2 ± 4.5) who had pre-discharge MAGGIC and 6MWT. The endpoint was all-cause mortality. Mild or moderate undernourishment was present in 54% of patients with no differences across BMI strata. The 12-month event rate was 7.7%. Deceased patients had a more compromised NS (CONUT 2.8 ± 1.5 vs 1.7 ± 1.3, p < 0.0001), and a more advanced HF (MAGGIC 28.2 ± 6.0 vs 22.0 ± 6.6, p < 0.0001; 6MWT 311.1 ± 102.2 vs. 408.9 ± 95.9 m, p < 0.0001). The 12-month mortality rate varied from 4% for well-nourished to 11% for undernourished patients (p = 0.008). At univariate analysis, the CONUT was predictive for all-cause mortality with a Hazard Ratio of 1.701 [95% CI 1.363-2.122], p < 0.0001. Multivariable analysis showed that the CONUT significantly added to the combination of MAGGIC and 6MWT and improved predictive discrimination and risk classification (c-index 0.82 [95% CI 0.75-0.88], integrated discrimination improvement 0.028 [95% CI 0.015-0.081]).

CONCLUSIONS

In HF patients assessment of NS, significantly improves prediction of 12-month mortality on top of the information provided by clinical evaluation and functional capacity and should be incorporated in the overall assessment of HF patients.

Isolation of a Defective Prion Mutant from Natural Scrapie

It is widely known that prion strains can mutate in response to modification of the replication environment and we have recently reported that prion mutations can occur in vitro during amplification of vole-adapted prions by Protein Misfolding Cyclic Amplification on bank vole substrate (bvPMCA). Here we exploited the high efficiency of prion replication by bvPMCA to study the in vitro propagation of natural scrapie isolates. Although in vitro vole-adapted PrP^Sc conformers were usually similar to the sheep counterpart, we repeatedly isolated a PrP^Sc mutant exclusively when starting from extremely diluted seeds of a single sheep isolate. The mutant and faithful PrP^Sc conformers showed to be efficiently autocatalytic in vitro and were characterized by different PrP protease resistant cores, spanning aa ∼155–231 and ∼80–231 respectively, and by different conformational stabilities. The two conformers could thus be seen as different bona fide PrP^Sc types, putatively accounting for prion populations with different biological properties. Indeed, once inoculated in bank vole the faithful conformer was competent for in vivo replication while the mutant was unable to infect voles, de facto behaving like a defective prion mutant. Overall, our findings confirm that prions can adapt and evolve in the new replication environments and that the starting population size can affect their evolutionary landscape, at least in vitro. Furthermore, we report the first example of “authentic” defective prion mutant, composed of brain-derived PrP^C and originating from a natural scrapie isolate. Our results clearly indicate that the defective mutant lacks of some structural characteristics, that presumably involve the central region ∼90–155, critical for infectivity but not for in vitro replication. Finally, we propose a molecular mechanism able to account for the discordant in vitro and in vivo behavior, suggesting possible new paths for investigating the molecular bases of prion infectivity.

Prions are unique infectious agents, consisting of PrP^Sc, a self-propagating aggregated conformer of the host-encoded prion protein PrP^C. Despite the absence of any nucleic acid information, prions exist as distinct strains that share the same amino acid sequence but differ in their conformation. Moreover, prions can mutate and are thus heterogeneous populations able to evolve and adapt to new replication environments. During in vitro amplification of sheep scrapie, we found that a prion mutant could be obtained from one natural isolate. The prion mutant identified was characterized in vivo and in vitro, showing unusual biochemical and biological features: a smaller than usual C-terminal proteinase resistant core of PrP^Sc, which spans aa ∼155–231, and the inability to propagate in vivo despite an efficient autocatalytic replication in vitro. With such a signature, we denoted the mutant as a “defective” prion mutant. We thus postulate a new hypothesis for the discrepancy between the in vitro and in vivo behavior of the defective mutant and suggest that the central PrP^Sc domain ∼90–160 might have a key role in prion replication. This work provides important new insights into the mechanism underpinning prion replication and has numerous implications for understanding the molecular requirements indispensable for prion infectivity.

Sex differences in food choices, adherence to dietary recommendations and plasma lipid profile in type 2 diabetes - The TOSCA.IT study

BACKGROUND AND AIMS

Diabetic women have a more adverse plasma lipid profile than men. Sex differences in dietary habits may play a role, but are little investigated. The study evaluates the quality of diet, adherence to the nutritional recommendations of the Diabetes and Nutrition Study Group and their relation with plasma lipid in men and women with diabetes.

METHODS AND RESULTS

We studied 2573 people, aged 50-75, enrolled in the TOSCA.IT study (clinicaltrials.gov; NCT00700856). Plasma lipids were measured centrally. Diet was assessed with a semi-quantitative food frequency questionnaire. Women had a more adverse plasma lipid profile than men. Women consumed significantly more legumes, vegetables, fruits, eggs, milk, vegetable oils, and added sugar, whereas men consumed more starchy foods, soft drinks and alcoholic beverages. This stands for a higher proportion (%) of energy intake from saturated fat and added sugar (12.0 ± 2.4 vs 11.5 ± 2.5 and 3.4 ± 3.2 vs 2.3 ± 3.2, P < 0.04), and a higher intake of fiber (11.2 ± 2.8 vs 10.4 ± 2.6 g/1000 Kcal/day) in women. Adherence to the recommendations for saturated fat and fiber consumption was associated with significantly lower LDL-cholesterol regardless of sex. Adherence to the recommendations for added sugars was associated with significantly lower triglycerides and higher HDL-cholesterol in men and women.

CONCLUSIONS

Men and women with diabetes show significant differences in adherence to nutritional recommendations, but sex differences in plasma lipid profile are unlikely to be explained by nutritional factors. Adherence to the nutritional recommendations is associated with a better plasma lipid profile regardless of sex, thus reinforcing the importance of substituting saturated for unsaturated fat sources, increasing fiber and reducing added sugar intake.

Risk Differences Between Prediabetes And Diabetes According To Breast Cancer Molecular Subtypes

Hyperglycemia and hyperinsulinemia may play a role in breast carcinogenesis and prediabetes and diabetes have been associated with increased breast cancer (BC) risk. However, whether BC molecular subtypes may modify these associations is less clear. We therefore investigated these associations in all cases and by BC molecular subtypes among women living in Southern Italy. Cases were 557 patients with non-metastatic incident BC and controls were 592 outpatients enrolled during the same period as cases and in the same hospital for skin-related non-malignant conditions. Adjusted multivariate logistic regression models were built to assess the risks of developing BC in the presence of prediabetes or diabetes. The analyses were repeated by strata of BC molecular subtypes: Luminal A, Luminal B, HER2+, and Triple Negative (TN). Prediabetes and diabetes were significantly associated with higher BC incidence after controlling for known risk factors (OR = 1.94, 95% CI 1.32-2.87 and OR = 2.46, 95% CI 1.38-4.37, respectively). Similar results were seen in Luminal A and B while in the TN subtype only prediabetes was associated with BC (OR = 2.43, 95% CI 1.11-5.32). Among HER2+ patients, only diabetes was significantly associated with BC risk (OR = 3.04, 95% CI 1.24-7.47). Furthermore, when postmenopausal HER2+ was split into hormone receptor positive versus negative, the association with diabetes remained significant only in the former (OR = 5.13, 95% CI 1.53-17.22). These results suggest that prediabetes and diabetes are strongly associated with BC incidence and that these metabolic conditions may be more relevant in the presence of breast cancer molecular subtypes with positive hormone receptors. J. Cell. Physiol. 232: 1144-1150, 2017. © 2016 Wiley Periodicals, Inc.

Comparative Effects of Roux-en-Y Gastric Bypass and Sleeve Gastrectomy on Glucose Homeostasis and Incretin Hormones in Obese Type 2 Diabetic Patients: A One-Year Prospective Study

The aim of the work was to compare the hormonal and the metabolic mechanisms involved in weight loss and remission of T2DM one year after Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) in morbidly obese type 2 diabetic (T2DM) patients. Insulin sensitivity, insulin secretion, and the gastrointestinal (GI) hormone response to a mixed meal test (MMT) were evaluated before and one year after BS (14 RYGB and 19 VSG). RYGB and VSG groups had similar characteristics at baseline. Weight loss at one year was similar in the 2 groups (ΔBMI%: - 32±10 and - 30±7%, p=0.546). Insulin sensitivity and insulin secretion improved similarly after either procedures with a similar rate in T2DM remission (86% in RYGB and 76% in VSG). Meal-stimulated GLP-1 levels increased after both procedures reaching significantly higher levels after RYGB (p=0.0001). GIP response to MMT decreased to a similar extent after the 2 interventions (p=0.977). Both fasting and post-meal ghrelin concentrations were markedly suppressed after VSG and significantly lower than RYGB (p=0.013 to p=0.035). The improvement of insulin sensitivity and beta-cell function was significantly associated with weight loss (p=0.014 to p=0.035), while no relation was found with the changes in GI hormones. In conclusion, in morbidly obese T2DM patients, RYGB and VSG result in similar improvements of the glucose status in the face of different GI hormonal pattern. Weight loss is the key determinant of diabetes remission one year after surgery.

The combination of UCP3-55CT and PPARγ2Pro12Ala polymorphisms affects BMI and substrate oxidation in two diabetic populations

BACKGROUND AND AIM

To evaluate the combined contribution of UCP3-55CT and PPARγ2 Pro12Ala polymorphisms as correlates of BMI, energy expenditure (REE) and substrate oxidation in people with type 2 diabetes.

METHODS AND RESULTS

Two independent population with type 2 diabetes were studied: population A, n = 272; population B, n = 269. Based on both UCP3 and PPARγ2 genotypes three groups were created. Carriers of the PPARγ2 Pro12Ala in combination with the CC genotype of UCP3 (ProAla/CC, group 1); carriers of only one of these genotypes (either CC/ProPro or CT-TT/ProAla, group 2); people with neither variants (CT-TT/ProPro, group 3). In both populations BMI (kg/m(2)) was highest in group 1, intermediate in group 2 and lowest in group 3, independent of energy intake (i.e 35.3 ± 6.7 vs 33.4 ± 5.4 vs 31.8 ± 3, p < 0.02, population A; 32.4 ± 4.2 vs 31.7 ± 3.8 vs 30.1 ± 2.7; p < 0.03, population B). People with the ProAla/CC genotype (group 1) showed similar REE, but lower lipid oxidation (10.9 vs 13.9 g/kg fat free mass/day; p = 0.04) and higher carbohydrate oxidation (23.6 vs 15.6 g/kg fat free mass/day; p = 0.02) than carriers of other genotypes.

CONCLUSIONS

The combination of UCP3-55 CC and PPARγ2 Pro12Ala genotypes is associated with significantly higher BMI than other PPARγ2-UCP3 genotype combinations, partly due to a reduced ability in lipids oxidation. The relative importance of these mechanism(s) may be different in non diabetic people.

A cationic tetrapyrrole inhibits toxic activities of the cellular prion protein

Prion diseases are rare neurodegenerative conditions associated with the conformational conversion of the cellular prion protein (PrP^C) into PrP^Sc, a self-replicating isoform (prion) that accumulates in the central nervous system of affected individuals. The structure of PrP^Sc is poorly defined, and likely to be heterogeneous, as suggested by the existence of different prion strains. The latter represents a relevant problem for therapy in prion diseases, as some potent anti-prion compounds have shown strain-specificity. Designing therapeutics that target PrP^C may provide an opportunity to overcome these problems. PrP^C ligands may theoretically inhibit the replication of multiple prion strains, by acting on the common substrate of any prion replication reaction. Here, we characterized the properties of a cationic tetrapyrrole [Fe(III)-TMPyP], which was previously shown to bind PrP^C, and inhibit the replication of a mouse prion strain. We report that the compound is active against multiple prion strains in vitro and in cells. Interestingly, we also find that Fe(III)-TMPyP inhibits several PrP^C-related toxic activities, including the channel-forming ability of a PrP mutant, and the PrP^C-dependent synaptotoxicity of amyloid-β (Aβ) oligomers, which are associated with Alzheimer’s Disease. These results demonstrate that molecules binding to PrP^C may produce a dual effect of blocking prion replication and inhibiting PrP^C-mediated toxicity.

Gerstmann-Sträussler-Scheinker disease subtypes efficiently transmit in bank voles as genuine prion diseases

Gerstmann-Sträussler-Scheinker disease (GSS) is an inherited neurodegenerative disorder associated with mutations in the prion protein gene and accumulation of misfolded PrP with protease-resistant fragments (PrP^res) of 6–8 kDa. With the exception of a few GSS cases characterized by co-accumulation of PrP^res of 21 kDa, efforts to transmit GSS to rodents have been unsuccessful. As a result, GSS subtypes exclusively associated with 6–8 kDa PrP^res have often been considered as non-transmissible proteinopathies rather than true prion diseases. We show that GSS with P102L, A117V and F198S mutations transmit efficiently and produce distinct pathological phenotypes in bank voles (M. glareolus), irrespective of the presence of 21 kDa PrP^res in the inoculum, demonstrating that GSS is a genuine prion disease characterized by both transmissibility and strain variation.

Glycaemic load versus carbohydrate counting for insulin bolus calculation in patients with type 1 diabetes on insulin pump

AIMS

To evaluate feasibility and effectiveness on short-term blood glucose control of using glycaemic load counting (GLC) versus carbohydrate counting (CC) for prandial insulin dosing in patients with type 1 diabetes (T1D).

METHODS

Nine T1D patients on insulin pump, aged 26-58 years, HbA1c 7.7 ± 0.8 % (61 ± 8.7 mmol/mol), participated in this real-life setting study. By a crossover design, patients were randomised to calculate their pre-meal insulin dose based on the insulin/glycaemic load ratio (GLC period) or the insulin/carbohydrate ratio (CC period) for 1 week, shifting to the alternate method for the next week, when participants duplicated their first week food plan. Over either week, a blind subcutaneous continuous glucose monitoring was performed, and a 7-day food record was filled in.

RESULTS

Total daily insulin doses (45 ± 10 vs. 44 ± 9 I.U.; M ± SD, p = 0.386) and basal infusion (26 ± 7 vs. 26 ± 8 I.U., p = 0.516) were not different during GLC and CC periods, respectively. However, the range of insulin doses (difference between highest and lowest insulin dose) was wider during GLC, with statistical significance at dinner (8.4 ± 6.2 vs. 6.0 ± 3.9 I.U., p = 0.041). Blood glucose iAUC after lunch was lower, albeit not significantly, during GLC than CC period (0.6 ± 8.6 vs. 3.4 ± 8.2 mmol/l∙3 h, p = 0.059). Postprandial glucose variability, evaluated as the maximal amplitude after meal (highest minus lowest glucose value), was significantly lower during GLC than CC period at lunch (4.22 ± 0.28 vs. 5.47 ± 0.39 mmol/l, p = 0.002) and dinner (3.89 ± 0.33 vs. 4.89 ± 0.33, p = 0.026).

CONCLUSIONS

Calculating prandial insulin bolus based on glycaemic load counting is feasible in a real-life setting and may improve postprandial glucose control in people with T1D.

Effects of bariatric surgery on markers of subclinical atherosclerosis and endothelial function: a meta-analysis of literature studies

BACKGROUND/OBJECTIVES

Several studies confirmed a significantly increased carotid intima-media thickness (IMT) and impaired flow-mediated dilation (FMD) and nitrate-mediated dilation (NMD) in obese subjects, but few data are available on the effects of bariatric surgery on these markers of cardiovascular (CV) risk. We performed a meta-analysis of studies evaluating changes in IMT, FMD and NMD in obese patients after bariatric surgery.

METHODS

A systematic search was performed in the PubMed, Web of Science, Scopus and EMBASE databases without any language or publication year restriction. The last search was performed in January 2015. In addition, the reference lists of all retrieved articles were manually reviewed. Prospective studies evaluating the impact of bariatric surgery on the markers of CV risk were included. Changes in IMT, FMD and NMD after bariatric surgery were expressed as mean differences (MD) with pertinent 95% confidence intervals (95% CIs). IMT has been expressed in millimeters (mm); FMD and NMD as percentage (%). Impact of clinical and demographic features on effect size was assessed by meta-regression.

RESULTS

Ten articles (314 obese patients) were included in the analysis. Six studies contained data on IMT (7 data sets; 206 patients), 8 studies on FMD (9 data sets; 269 patients) and 4 on NMD (4 data sets; 149 patients). After bariatric surgery, there was a significant reduction of IMT (MD: -0.17 mm; 95% CI: -0.290, -0.049; P=0.006) and a significant improvement in FMD (MD: 5.65%; 95% CI: 2.87, 8.03; P<0.001), whereas NMD did not change (MD: 2.173%; 95% CI: -0.796, 5.142; P=0.151). Interestingly, percentage of changes in the body mass index were associated with changes in IMT (Z=11.52, P<0.001), FMD (Z=-4.26, P<0.001) and NMD (Z=-3.81, P<0.001).

CONCLUSIONS

Despite heterogeneity among studies, bariatric surgery is associated with improvement of subclinical atherosclerosis and endothelial function. These effects may significantly contribute to the reduction of the CV risk after bariatric surgery.

Glycemic index, glycemic load and glycemic response: An International Scientific Consensus Summit from the International Carbohydrate Quality Consortium (ICQC)

BACKGROUND AND AIMS

The positive and negative health effects of dietary carbohydrates are of interest to both researchers and consumers.

METHODS

International experts on carbohydrate research held a scientific summit in Stresa, Italy, in June 2013 to discuss controversies surrounding the utility of the glycemic index (GI), glycemic load (GL) and glycemic response (GR).

RESULTS

The outcome was a scientific consensus statement which recognized the importance of postprandial glycemia in overall health, and the GI as a valid and reproducible method of classifying carbohydrate foods for this purpose. There was consensus that diets low in GI and GL were relevant to the prevention and management of diabetes and coronary heart disease, and probably obesity. Moderate to weak associations were observed for selected cancers. The group affirmed that diets low in GI and GL should always be considered in the context of diets otherwise understood as healthy, complementing additional ways of characterizing carbohydrate foods, such as fiber and whole grain content. Diets of low GI and GL were considered particularly important in individuals with insulin resistance.

CONCLUSIONS

Given the high prevalence of diabetes and pre-diabetes worldwide and the consistency of the scientific evidence reviewed, the expert panel confirmed an urgent need to communicate information on GI and GL to the general public and health professionals, through channels such as national dietary guidelines, food composition tables and food labels.

Influence of dietary fat and carbohydrates proportions on plasma lipids, glucose control and low-grade inflammation in patients with type 2 diabetes-The TOSCA.IT Study

PURPOSE

The optimal macronutrient composition of the diet for the management of type 2 diabetes is debated, particularly with regard to the ideal proportion of fat and carbohydrates. The aim of the study was to explore the association of different proportions of fat and carbohydrates of the diet-within the ranges recommended by different guidelines-with metabolic risk factors.

METHODS

We studied 1785 people with type 2 diabetes, aged 50-75, enrolled in the TOSCA.IT Study. Dietary habits were assessed using a validated food-frequency questionnaire (EPIC). Anthropometry, fasting lipids, HbA1c and C-reactive protein (CRP) were measured.

RESULTS

Increasing fat intake from <25 to ≥35 % is associated with a significant increase in LDL-cholesterol, triglycerides, HbA1c and CRP (p < 0.05). Increasing carbohydrates intake from <45 to ≥60 % is associated with significantly lower triglycerides, HbA1c and CRP (p < 0.05). A fiber intake ≥15 g/1000 kcal is associated with a better plasma lipids profile and lower HbA1c and CRP than lower fiber consumption. A consumption of added sugars of ≥10 % of the energy intake is associated with a more adverse plasma lipids profile and higher CRP than lower intake.

CONCLUSIONS

In people with type 2 diabetes, variations in the proportion of fat and carbohydrates of the diet, within the relatively narrow ranges recommended by different nutritional guidelines, significantly impact on the metabolic profile and markers of low-grade inflammation. The data support the potential for reducing the intake of fat and added sugars, preferring complex, slowly absorbable, carbohydrates.

Clinical efficacy of bariatric surgery versus liraglutide in patients with type 2 diabetes and severe obesity: a 12-month retrospective evaluation

AIMS

To evaluate the clinical efficacy of bariatric surgery vs medical therapy with liraglutide on weight loss, glycemic control and cardiovascular risk profile in patients with type 2 diabetes and severe obesity.

METHODS

A retrospective evaluation was conducted in 31 patients with type 2 diabetes and severe obesity who had undergone bariatric surgery and in 31 patients with type 2 diabetes and comparable body weight who had added liraglutide to their background medical treatment in the period 2009-2013. Anthropometric parameters, glycemic control, treatment of diabetes and other comorbidities, safety and side effects before and 12 months after treatment were assessed.

RESULTS

Age was 47 ± 8 years (mean ± SD) in bariatric surgery and 56 ± 9 years in medical treatment group (p < 0.001); body mass index before treatment was 44 ± 7 and 40 ± 4 kg/m(2) in bariatric surgery and medical treatment, respectively (p = 0.03). Twelve months after treatment, average weight loss was 38 ± 15 kg among bariatric surgery patients, and 5 ± 8 kg in medical treatment group (p < 0.001). Glycemic control improved in both groups with greater improvement in bariatric surgery patients. The UKPDS risk score decreased in both groups, although it remained higher in medical treatment than in bariatric surgery patients (p < 0.001). Of note, almost 60 % of patients on liraglutide met the target of glycated hemoglobin <7 % (53 mmol/mol) and lost ≥5 % of body weight.

CONCLUSIONS

In severely obese type 2 diabetic patients, bariatric surgery reduced body weight and improved overall metabolic control to a greater extent than medical treatment. Randomized clinical studies are necessary.

Functional foods and cardiometabolic diseases* International Task Force for Prevention of Cardiometabolic Diseases

Mounting evidence supports the hypothesis that functional foods containing physiologically-active components may be healthful. Longitudinal cohort studies have shown that some food classes and dietary patterns are beneficial in primary prevention, and this has led to the identification of putative functional foods. This field, however, is at its very beginning, and additional research is necessary to substantiate the potential health benefit of foods for which the diet-health relationships are not yet scientifically validated. It appears essential, however, that before health claims are made for particular foods, in vivo randomized, double-blind, placebo controlled trials of clinical end-points are necessary to establish clinical efficacy. Since there is need for research work aimed at devising personalized diet based on genetic make-up, it seems more than reasonable the latter be modeled, at present, on the Mediterranean diet, given the large body of evidence of its healthful effects. The Mediterranean diet is a nutritional model whose origins go back to the traditional dietadopted in European countries bordering the Mediterranean sea, namely central and southern Italy, Greece and Spain; these populations have a lower incidence of cardiovascular diseases than the North American ones, whose diet is characterized by high intake of animal fat. The meeting in Naples and this document both aim to focus on the changes in time in these two different models of dietary habits and their fall out on public health.

A whole-grain cereal-based diet lowers postprandial plasma insulin and triglyceride levels in individuals with metabolic syndrome

BACKGROUND AND AIM

Until recently, very few intervention studies have investigated the effects of whole-grain cereals on postprandial glucose, insulin and lipid metabolism, and the existing studies have provided mixed results. The objective of this study was to evaluate the effects of a 12-week intervention with either a whole-grain-based or a refined cereal-based diet on postprandial glucose, insulin and lipid metabolism in individuals with metabolic syndrome.

METHODS AND RESULTS

Sixty-one men and women age range 40-65 years, with the metabolic syndrome were recruited to participate in this study using a parallel group design. After a 4-week run-in period, participants were randomly assigned to a 12-week diet based on whole-grain products (whole-grain group) or refined cereal products (control group). Blood samples were taken at the beginning and end of the intervention, both fasting and 3 h after a lunch, to measure biochemical parameters. Generalized linear model (GLM) was used for between-group comparisons. Overall, 26 participants in the control group and 28 in the whole-grain group completed the dietary intervention. Drop-outs (five in the control and two in the whole-grain group) did not affect randomization. After 12 weeks, postprandial insulin and triglyceride responses (evaluated as average change 2 and 3 h after the meal, respectively) decreased by 29% and 43%, respectively, in the whole-grain group compared to the run-in period. Postprandial insulin and triglyceride responses were significantly lower at the end of the intervention in the whole-grain group compared to the control group (p = 0.04 and p = 0.05; respectively) whereas there was no change in postprandial response of glucose and other parameters evaluated.

CONCLUSIONS

A twelve week whole-grain cereal-based diet, compared to refined cereals, reduced postprandial insulin and triglycerides responses. This finding may have implications for type 2 diabetes risk and cardiovascular disease.

Test meals rich in marine long-chain n-3 polyunsaturated fatty acids increase postprandial chylomicron response

Postprandial lipid abnormalities are considered an independent cardiovascular risk factor. Hence, it is important to find nutritional strategies that are able to positively influence these abnormalities. Since the effect of n-3 polyunsaturated fatty acids (PUFA) and polyphenols on postprandial lipids in humans is still under debate, we evaluated the acute response of triglyceride-rich lipoproteins to test meals that are naturally rich in polyphenols and/or marine long-chain (LC) n-3 PUFAs. We hypothesized that LC n-3 PUFA would have a different effect on chylomicron and very low density lipoproteins when compared with polyphenols or their combination. We randomly assigned 78 individuals who were at high cardiometabolic risk to 4 isoenergetic diets. These diets only differed in amount of LC n-3 PUFA and/or polyphenols. Prior to starting the intervention, each subject underwent a test meal similar to the type of diet assigned: low in LC n-3 PUFA and polyphenols (control), rich in LC n-3 PUFA and low in polyphenols, rich in polyphenols and low in LC n-3 PUFA, or rich in both. Blood samples were taken before and up to 6 hours after the test meal in order to evaluate cholesterol and triglycerides (plasma and triglyceride-rich lipoprotein), apolipoprotein B-48 (large very low density lipoprotein), glucagon-like peptide-1, and free fatty acid plasma levels. The levels of chylomicron cholesterol and triglyceride in response to the test meal rich in LC n-3 PUFA were significantly higher than after the control meal (P = .037 and P = .018); there was no difference in the other variables. In conclusion, this study indicates that acute administration of marine LC n-3 PUFA increases postprandial chylomicron response in contrast with their lowering chronic effects. These differences underline the importance of understanding the acute and chronic effects of nutritional, as well as of other types of, interventions.

Dietary fat differentially modulate the mRNA expression levels of oxidative mitochondrial genes in skeletal muscle of healthy subjects

BACKGROUND AND AIMS

Different types of dietary fats exert differential effects on glucose and lipid metabolism. Our aim was to evaluate the impact of different dietary fats on the expression of skeletal muscle genes regulating mitochondrial replication and function in healthy subjects.

METHODS AND RESULTS

Ten healthy subjects (age 29 ± 3 years; BMI 25.0 ± 3 kg/m(2)) received in a random order a test meal with the same energy content but different composition in macronutrients and quality of fat: Mediterranean (MED) meal, SAFA meal (Lipid 66%, saturated 36%) and MUFA meal (Lipid 63%, monounsaturated 37%). At fast and after 180 min, a fine needle aspiration was performed from the vastus lateralis for determination of mitochondrial gene expression by quantitative PCR. No difference in glucose and triglyceride response was observed between the three meals, while NEFA levels were significantly higher following fat-rich meals compared to MED meal (p < 0.002-0.0001). MED meal was associated with an increased expression, albeit not statistically significant, of some genes regulating both replication and function. Following MUFA meal, a significant increase in the expression of PGC1β (p = 0.02) and a reduction in the transcription factor PPARδ (p = 0.006) occurred with no change in the expression of COX and GLUT4 genes. In contrast, SAFA meal was associated with a marked reduction in the expression of COX (p < 0.001) PFK (p < 0.003), LPL (p = 0.002) and GLUT4 (p = 0.009) genes.

CONCLUSION

Dietary fats differentially modulate gene transcriptional profile since saturated, but not monounsaturated fat, downregulate the expression of genes regulating muscle glucose transport and oxidation.

Lower incidence of macrovascular complications in patients on insulin glargine versus those on basal human insulins: a population-based cohort study in Italy

BACKGROUND AND AIM

The aim of this study was to compare the use of insulin glargine and intermediate/long-acting human insulin (HI) in relation to the incidence of complications in diabetic patients.

METHODS AND RESULTS

A population-based cohort study was conducted using administrative data from four local health authorities in the Abruzzo Region (900,000 inhabitants). Diabetic patients without macrovascular diseases and treated with either intermediate/long-acting HI or glargine were followed for 3-years; the incidence of diabetic (macrovascular, microvascular and metabolic) complications was ascertained by hospital discharge claims and estimated using Cox proportional hazard models. Propensity score (PS) matching was also used to adjust for significant differences in the baseline characteristics between the two groups.

RESULTS

Overall, 1921 diabetic patients were included: 744 intermediate/long-acting HI and 1177 glargine users. During the 3-year follow-up, 209 (28.1%) incident events of any diabetic complication occurred in the intermediate/long-acting HI and 159 (13.5%) in the glargine group. After adjustment for covariates, glargine users had an HR (95% CI) of 0.57 (0.44-0.74) for any diabetic complication and HRs of 0.61 (0.44-0.84), 0.58 (0.33-1.04) and 0.35 (0.18-0.70) for macrovascular, microvascular and metabolic complications, respectively, compared to intermediate/long-acting HI users. PS analyses supported these findings.

CONCLUSIONS

The use of glargine is associated with a lower risk of macrovascular complications compared with traditional basal insulins. However, limitations inherent to the study design including the short length of observation and the lack of data on metabolic control or diabetes duration, do not allow us to consider this association as a proof of causality.

The results of Look AHEAD do not row against the implementation of lifestyle changes in patients with type 2 diabetes

The Look AHEAD trial, evaluating the effects of weight loss on cardiovascular (CV) morbidity and mortality in overweight/obese people with type 2 diabetes (T2D), was interrupted after a median 9.5-year follow-up because the incidence of CV events was not different between the Intensive Lifestyle Intervention (ILI) and the control groups, and unlikely to statistically change thereafter. This made health providers and patients wondering about clinical value of diet and physical exercise in diabetic patients. Many factors may have made difficult to ascertain benefits of lifestyle intervention, besides the lower than predicted CV event rates. Among others, LDL-cholesterol was lowered more, with a higher use of statins, in the control group. Anyhow, ILI significantly improved numerous health conditions, including quality of life, CV risk factors and blood glucose control, with more diabetes remissions and less use of insulin. The intervention aimed at weight loss by reducing fat calories, and using meal replacements and, eventually, orlistat, likely underemphasizing dietary composition. There is suggestive evidence, in fact, that qualitative changes in dietary composition aiming at higher consumption of foods rich in fiber and with a high vegetable/animal fat ratio favorably influence CV risk in T2D patients. In conclusion, the Look AHEAD showed substantial health benefits of lifestyle modifications. Prevention of CV events may need higher attention to dietary composition, contributing to stricter control of CV risk factors. As a better health-related quality of life in people with diabetes is an important driver of our clinical decisions, efforts on early implementation of behavioral changes through a multifactorial approach are strongly justified.

A CHO/fibre diet reduces and a MUFA diet increases postprandial lipaemia in type 2 diabetes: no supplementary effects of low-volume physical training

The aim of the study was to evaluate the effects of a supervised physical training added to a healthy diet-rich in either carbohydrate and fibre (CHO/fibre) or monounsaturated fatty acids (MUFA)-on postprandial dyslipidaemia, an independent cardiovascular risk factor particularly relevant in type 2 diabetes (T2D). Participants were forty-five overweight/obese subjects with T2D, of both genders, in good blood glucose control with diet or diet+metformin, with normal fasting plasma lipids. According to a parallel groups 2 × 2 factorial design, participants were randomized to an 8-week isoenergetic intervention with a CHO/fibre or a MUFA diet, with or without a supervised low-volume aerobic training programme. The main outcome of the study was the incremental area under the curve (iAUC) of lipid concentrations in the plasma chylomicron+VLDL lipoprotein fraction, isolated by preparative ultracentrifugation (NCT01025856). Body weight remained stable during the trial in all groups. Physical fitness slightly improved with training (VO2 peak, 16 ± 4 vs. 15 ± 3 ml/kg/min, M ± SD, p < 0.05). Postprandial triglyceride and cholesterol iAUCs in plasma and chylomicron+VLDL fraction decreased after the CHO/fibre diet, but increased after the MUFA diet with a significant effect for diet by two-way ANOVA (p < 0.05). The addition of exercise training to either dietary intervention did not significantly influence postprandial lipid response. A diet rich in carbohydrates and fibre reduced postprandial triglyceride-rich lipoproteins compared with a diet rich in MUFA in patients with T2D. A supervised low-volume physical training did not significantly influence these dietary effects.

The energy intake modulates the association of the -55CT polymorphism of UCP3 with body weight in type 2 diabetic patients

BACKGROUND

Previous association studies of the -55CT polymorphism of the uncoupling protein 3 (UCP3) gene with body mass index (BMI) have provided inconsistent results. The study aim is twofold: (1) to evaluate the association of the -55CT polymorphism of UCP3 with BMI in two independent populations to verify the reproducibility of the finding; (2) to evaluate whether this association is modulated by energy intake.

METHODS

Study participants are 736 males and females with type 2 diabetes belonging to independent populations (N=394 population 1; N=342 population 2). Anthropometry and laboratory parameters were measured; in population 2, energy intake and physical exercise were also assessed.

RESULTS

The -55CT polymorphism was associated with a significantly lower BMI in population 1 (27.8±3.9 vs 28.9±4.6 kg m(-2); P<0.02), the finding was confirmed in population 2 (that is, 30.3±6.0 vs 32.1±5.9 kg m(-2); P<0.01) independent of gender, age, HbA1c, use of drugs and energy intake. To evaluate the role of diet in population 2, the study participants were stratified by genotype and tertiles of energy intake. In both genotype groups, BMI increased with increasing caloric intake with a significant trend (P<0.001), the BMI difference between the two genotype groups was large and statistically significant in the lower tertile (27.6 vs 31.2 kg m(-2); P<0.001), intermediate in the second tertile and negligible in the upper tertile (32.8 vs 32.9; kg m(-2); nonsignificant). The multivariate regression analysis confirmed a significant interaction between genotype and energy intake as correlates of BMI independent of age, gender, glucose control, physical activity and medications for diabetes (P=0.004).

CONCLUSIONS

The study replicates in two independent populations the association between the -55CT polymorphism of UCP3 and a lower BMI. This association was modulated by energy intake, thus suggesting that the unmeasured effect of diet may partly account for inconsistencies of prior association studies.

The association of hs-CRP with fasting and postprandial plasma lipids in patients with type 2 diabetes is disrupted by dietary monounsaturated fatty acids

The aim of the study was to evaluate whether two dietary approaches recommended for diabetes mellitus and cardiovascular prevention-high-MUFA or complex carbohydrates/fiber-differently influence inflammation. A 4-week crossover study in 12 individuals with type 2 diabetes was performed. Fasting and postprandial hs-CRP plasma levels were not significantly different after a high-carbohydrate/high-fiber/low-glycemic index (CHO/fiber) and a high-MUFA diet. Compared with fasting, hs-CRP levels decreased significantly after the MUFA but not after the CHO/fiber meal. Triglyceride-rich lipoproteins were significantly lower after the CHO/fiber than the MUFA diet. At fasting and postprandially, hs-CRP correlated with triglyceride in whole plasma, chylomicrons, small and large VLDL after the CHO/fiber but not after the MUFA diet. In conclusion, a MUFA-rich diet and a carbohydrate/fiber-rich diet induced similar effects on plasma hs-CRP concentrations. However, these dietary approaches seem to influence hs-CRP levels through different mechanisms. i.e., direct acute postprandial effects by MUFA and triglyceride-rich lipoproteins mediated effects by CHO/fiber.

Chronic wasting disease in bank voles: characterisation of the shortest incubation time model for prion diseases

In order to assess the susceptibility of bank voles to chronic wasting disease (CWD), we inoculated voles carrying isoleucine or methionine at codon 109 (Bv109I and Bv109M, respectively) with CWD isolates from elk, mule deer and white-tailed deer. Efficient transmission rate (100%) was observed with mean survival times ranging from 156 to 281 days post inoculation. Subsequent passages in Bv109I allowed us to isolate from all CWD sources the same vole-adapted CWD strain (Bv(109I)CWD), typified by unprecedented short incubation times of 25-28 days and survival times of ∼35 days. Neuropathological and molecular characterisation of Bv(109I)CWD showed that the classical features of mammalian prion diseases were all recapitulated in less than one month after intracerebral inoculation. Bv(109I)CWD was characterised by a mild and discrete distribution of spongiosis and relatively low levels of protease-resistant PrP(Sc) (PrP(res)) in the same brain regions. Despite the low PrP(res) levels and the short time lapse available for its accumulation, end-point titration revealed that brains from terminally-ill voles contained up to 10(8,4) i.c. ID50 infectious units per gram. Bv(109I)CWD was efficiently replicated by protein misfolding cyclic amplification (PMCA) and the infectivity faithfully generated in vitro, as demonstrated by the preservation of the peculiar Bv(109I)CWD strain features on re-isolation in Bv109I. Overall, we provide evidence that the same CWD strain was isolated in Bv109I from the three-cervid species. Bv(109I)CWD showed unique characteristics of "virulence", low PrP(res) accumulation and high infectivity, thus providing exceptional opportunities to improve basic knowledge of the relationship between PrP(Sc), neurodegeneration and infectivity.

Addition of either pioglitazone or a sulfonylurea in type 2 diabetic patients inadequately controlled with metformin alone: impact on cardiovascular events. A randomized controlled trial

BACKGROUND AND AIMS

Metformin is the first-line therapy in type 2 diabetes. In patients inadequately controlled with metformin, the addition of a sulfonylurea or pioglitazone are equally plausible options to improve glycemic control. However, these drugs have profound differences in their mechanism of action, side effects, and impact on cardiovascular risk factors. A formal comparison of these two therapies in terms of cardiovascular morbidity and mortality is lacking. The TOSCA.IT study was designed to explore the effects of adding pioglitazone or a sulfonylurea on cardiovascular events in type 2 diabetic patients inadequately controlled with metformin.

METHODS

Multicentre, randomized, open label, parallel group trial of 48 month duration. Type 2 diabetic subjects, 50-75 years, BMI 20-45 Kg/m(2), on secondary failure to metformin monotherapy will be randomized to add-on a sulfonylurea or pioglitazone. The primary efficacy outcome is a composite endpoint of all-cause mortality, nonfatal myocardial infarction, nonfatal stroke, and unplanned coronary revascularization. Principal secondary outcome is a composite ischemic endpoint of sudden death, fatal and non-fatal myocardial infarction and stroke, endovascular or surgical intervention on the coronary, leg or carotid arteries, major amputations. Side effects, quality of life and economic costs will also be evaluated. Efficacy, safety, tolerability, and study conduct will be monitored by an independent Data Safety Monitoring Board. End points will be adjudicated by an independent external committee.

CONCLUSIONS

TOSCA.IT is the first on-going study investigating the head-to-head comparison of adding a sulfonylurea or pioglitazone to existing metformin treatment in terms of hard cardiovascular outcomes.

REGISTRATION

Clinicaltrials.gov ID NCT00700856.

Septic arthritis in children

Osteoarticular infections are a form of diagnostic and therapeutic emergency in infants and children, even if relatively rare. Despite decades of experience with different protocols, and multiple clinical trials, today it is still difficult to determine what kind of antibiotics is really effective, what kind of associations are required, which is the optimal time range of a treatment, when and on which subjects to base the transition from a parenteral treatment to an oral one. Current philosophy aims more and more at reducing hospitalization and costs, and wants to decrease the discomfort in the family. The purpose of these guidelines is to promote a reasoned clinical and therapeutic approach, in a context of diagnostic probabilities that offer the best chance of success in reducing hospitalization with a rapid transition to an oral treatment, and then outpatient, and thus educing totally the processing time.

Global cardiovascular risk management in different Italian regions: an analysis of the Evaluation of Final Feasible Effect of Control Training and Ultra Sensitisation (EFFECTUS) educational program

BACKGROUND AND AIM

The Final Evaluation Feasible Effect of Ultra Control Training and Sensitization (EFFECTUS) is an educational program, aimed at improving global CV risk stratification and management in Italy. The present study evaluates differences on clinical approach to global CV risk among physicians involved in the EFFECTUS program and stratified in three geographical macro-areas (North, Center, South) of our Country.

METHODS AND RESULTS

Physicians were asked to submit data already available in their medical records, covering the first 10 adult outpatients, consecutively seen in the month of May 2006. Overall, 1.078 physicians (27% females, aged 50 ± 7 years) collected data of 9.904 outpatients (46.5% females, aged 67 ± 9 years), among which 3.219 (32.5%) were residents in Northern, 3.652 (36.9%) in Central and 3.033 (30.6%) in Southern Italy. A significantly higher prevalence of major CV risk factors, including obesity, physical inactivity, hypertension and diabetes, was recorded in Southern than in other areas. Accordingly, Southern physicians more frequently prescribed antihypertensive, glucose and lipid lowering agents than other physicians, who paid significantly more attention to life-style changes in their clinical practice.

CONCLUSIONS

This analysis of the EFFECTUS study demonstrates a high prevalence of CV risk factors in Italy, particularly in Southern areas, and indicates some important discrepancies in the clinical management of global CV risk among physcians working in different Italian regions.

Whole grain intake in relation to body weight: from epidemiological evidence to clinical trials

This viewpoint aims to 1) review the available scientific literature on the relationship between whole grain consumption and body weight regulation; 2) evaluate the potential mechanisms whereby whole grain intake may help reduce overweight and 3) try to understand why epidemiological studies and clinical trials provide diverging results on this topic. All the prospective epidemiological studies demonstrate that a higher intake of whole grains is associated with lower BMI and body weight gain. However, these results do not clarify whether whole grain consumption is simply a marker of a healthier lifestyle or a factor favoring "per se" lower body weight. Habitual whole grain consumption seems to cause lower body weight by multiple mechanisms such as lower energy density of whole grain based products, lower glycemic index, fermentation of non digestible carbohydrates (satiety signals) and finally by modulating intestinal microflora. In contrast with epidemiological evidence, the results of few clinical trials do not confirm that a whole grain low-calorie diet is more effective in reducing body weight than a refined cereal diet, but their results may have been affected by small sample size or short duration of the intervention. Therefore, further intervention studies with adequate methodology are needed to clarify this question. For the time being, whole grain consumption can be recommended as one of the features of the diet that may help control body weight but also because is associated with a lower risk to develop type 2 diabetes, cardiovascular diseases and cancer.

Impact of physicians' age on the clinical management of global cardiovascular risk: analysis of the results of the Evaluation of Final Feasible Effect of Control Training and Ultra Sensitisation Educational Programme

AIM

To evaluate the potential impact of physicians' age on global cardiovascular (CV) risk management in the population of the Evaluation of Final Feasible Effect of Ultra Control Training and Sensitisation (EFFECTUS) study.

METHODS

Involved physicians were stratified into three age groups (≤ 45, 46-55 and > 55 years), and asked to provide clinical data covering the first 10 adult outpatients, consecutively seen in May 2006.

RESULTS

Overall 1078 physicians, among whom 219 (20%) were aged ≤ 45, 658 (61%) between 46 and 55, and 201 (19%) > 55 years, collected data of 9904 outpatients (46.5% female patients, aged 67 ± 9 years), who were distributed into three corresponding groups: 2010 (20%), 6111 (62%) and 1783 (18%), respectively. A higher prevalence of myocardial infarction and stroke was recorded by younger physicians rather than those aged > 46 years. Older physicians frequently recommended life-style changes, whereas a higher number of antihypertensive, antiplatelet, glucose and lipid-lowering prescriptions was prescribed by physicians aged ≤ 45 years.

CONCLUSIONS

This analysis of the EFFECTUS study indicates a higher prevalence of vascular diseases among outpatients who were followed by younger physicians, who prescribed a higher number of CV drugs than older physicians. These older physicians have more attitude for prescribing favourable life-style changes than younger physicians.

Effects of meals with different glycaemic index on postprandial blood glucose response in patients with Type 1 diabetes treated with continuous subcutaneous insulin infusion

OBJECTIVE

To evaluate the impact of high-glycaemic index and low-glycaemic index meals on postprandial blood glucose in patients with Type 1 diabetes treated with continuous subcutaneous insulin infusion.

METHODS

Sixteen patients with Type 1 diabetes under continuous subcutaneous insulin infusion treatment, age 36±0.5 years (mean±sem), HbA(1c) 7.6±0.2% (56±1.1 mmol/mol), consumed two test meals with an identical macronutrient composition, but with a different glycaemic index: 59 vs. 90. Blood glucose was checked before the test meal and every 30 min thereafter for 180 min. The same preprandial insulin dose was administered on the two occasions.

RESULTS

Blood glucose concentrations following the low-glycaemic index meal were significantly lower than those of the high-glycaemic index meal (P<0.05 to P<0.01). The blood glucose area under the curve after the low-glycaemic index meal was 20% lower than after the high-glycaemic meal (P=0.006).

CONCLUSIONS

  Our data show that meals with the same carbohydrate content but a different glycaemic index produce clinically significant differences in postprandial blood glucose.