Obesity and Aging.

The obesity epidemic in aging populations poses significant public health concerns for greater morbidity and mortality risk. Age-related increased adiposity is multifactorial and often associated with reduced lean body mass. The criteria used to define obesity by body mass index in younger adults may not appropriately reflect age-related body composition changes. No consensus has been reached on the definition of sarcopenic obesity in older adults. Lifestyle interventions are generally recommended as initial therapy; however, these approaches have limitations in older adults. Similar benefits in older compared with younger adults are reported with pharmacotherapy, however, large randomized clinical trials in geriatric populations are lacking.

Endogenous Leptin Concentrations Poorly Predict Metreleptin Response in Patients With Partial Lipodystrophy.

CONTEXT: Leptin replacement with metreleptin improves glycemia and hypertriglyceridemia in severely hypoleptinemic patients with generalized lipodystrophy (GLD), but its effects are variable in partially leptin-deficient patients with partial lipodystrophy (PLD). OBJECTIVE: Compare 3 leptin assays (Study I); identify diagnostic performance of leptin assays to detect responders to metreleptin for each assay (Study II). DESIGN: Study I: cross-sectional analysis of average bias between leptin assays. Study II: retrospective analysis of diagnostic accuracy of potential leptin cut points to detect clinical responders to metreleptin. SETTING: National Institutes of Health; University of Michigan. PARTICIPANTS AND INTERVENTIONS: Study I: Metreleptin-naïve patients with lipodystrophy (GLD, n = 33, PLD, n = 67) and healthy volunteers (n = 239). Study II: GLD (n = 66) and PLD (n = 84) patients treated with metreleptin for 12 months. OUTCOME MEASURES: Leptin concentrations by Millipore radioimmunoassay (RIA), Millipore enzyme-linked immunosorbent assay (MELISA), and R&D Systems enzyme-linked immunosorbent assay (RDELISA). Response to metreleptin therapy was defined as either reduction ≥1.0% in A1c or ≥30% in serum triglycerides. RESULTS: RDELISA measured 3.0 ± 9.5 ng/mL higher than RIA; MELISA measured 11.0 ± 17.8 and 14.0 ±19.2 less than RIA and RDELISA, respectively. Leptin by RIA, MELISA, and RDELISA modestly predicted metreleptin response in GLD + PLD [receiver operating characteristic (ROC) area under the curve (AUC) 0.74, 0.69, and 0.71, respectively; P < 0.01 for all] with lower predictive power in PLD (ROC AUC 0.63, 0.61 and 0.65, respectively; P > 0.05 for all). The only reproducible cut point identified on sensitivity analyses was RIA leptin 7.2 ng/mL (sensitivity 56%; specificity 78%). CONCLUSIONS: Three common leptin assays are not interchangeable, and a reliable cut point to select responders to metreleptin was not identified.

Efficacy of Metreleptin Treatment in Familial Partial Lipodystrophy Due to PPARG vs LMNA Pathogenic Variants.

CONTEXT: Familial partial lipodystrophy (FPLD) is most commonly caused by pathogenic variants in LMNA and PPARG. Leptin replacement with metreleptin has largely been studied in the LMNA group. OBJECTIVE: To understand the efficacy of metreleptin in PPARG vs LMNA pathogenic variants and investigate predictors of metreleptin responsiveness. DESIGN: Subgroup analysis of a prospective open-label study of metreleptin in lipodystrophy. SETTING: National Institutes of Health, Bethesda, Maryland. PARTICIPANTS: Patients with LMNA (n = 22) or PPARG pathogenic variants (n = 7), leptin <12 ng/mL, and diabetes, insulin resistance, or high triglycerides. INTERVENTION: Metreleptin (0.08 to 0.16 mg/kg) for 12 months. OUTCOME: Hemoglobin A1c (HbA1c), lipids, and medication use at baseline and after 12 months. RESULTS: Baseline characteristics were comparable in patients with PPARG and LMNA: HbA1c, 9.2 ± 2.3 vs 7.8 ± 2.1%; median [25th, 75th percentile] triglycerides, 1377 [278, 5577] vs 332 [198, 562] mg/dL; leptin, 6.3 ± 3.8 vs 5.5 ± 2.5 ng/mL (P > 0.05). After 12 months of metreleptin, HbA1c declined to 7.7 ± 2.4 in PPARG and 7.3 ± 1.7% in LMNA; insulin requirement decreased from 3.8 [2.7, 4.3] to 2.1 [1.6, 3.0] U/kg/d in PPARG and from 1.7 [1.3, 4.4] to 1.2 [1.0, 2.3] U/kg/d in LMNA (P < 0.05). Triglycerides decreased to 293 [148, 406] mg/dL in LMNA (P < 0.05), but changes were not significant in PPARG: 680 [296, 783] mg/dL at 12 months (P = 0.2). Both groups were more likely to experience clinically relevant triglyceride (≥30%) or HbA1c (≥1%) reduction with metreleptin if they had baseline triglycerides ≥500 mg/dL or HbA1c >8%. CONCLUSION: Metreleptin resulted in similar metabolic improvements in patients with LMNA and PPARG pathogenic variants. Our findings support the efficacy of metreleptin in patients with the two most common genetic causes of FPLD.

"Fat Shadows" From DXA for the Qualitative Assessment of Lipodystrophy: When a Picture Is Worth a Thousand Numbers.

OBJECTIVE: Lipodystrophy syndromes are a heterogeneous group of disorders associated with selective absence of fat. Currently, the diagnosis is established only clinically. RESEARCH DESIGN AND METHODS: We developed a new method from DXA scans called a "fat shadow," which is a color-coded representation highlighting only the fat tissue. We conducted a blinded retrospective validation study to assess its usefulness for the diagnosis of lipodystrophy syndromes. RESULTS: We evaluated the fat shadows from 16 patients (11 female and 5 male) with generalized lipodystrophy (GL), 57 (50 female and 7 male) with familial partial lipodystrophy (FPLD), 2 (1 female and 1 male) with acquired partial lipodystrophy, and 126 (90 female and 36 male) control subjects. FPLD was differentiated from control subjects with 85% sensitivity and 96% specificity (95% CIs 72-93 and 91-99, respectively). GL was differentiated from nonobese control subjects with 100% sensitivity and specificity (95% CIs 79-100 and 92-100, respectively). CONCLUSIONS: Fat shadows provided sufficient qualitative information to infer clinical phenotype and differentiate these patients from appropriate control subjects. We propose that this method could be used to support the diagnosis.

Cognitive Function in Individuals with Normal Weight Obesity: Results from the Third National Health and Nutrition Examination Survey (NHANES III).

BACKGROUND/OBJECTIVE: Normal weight obesity (NWO) is associated with increased risk of metabolic syndrome, cardiovascular- and all-cause mortality. However, no data have been reported on the relationship between adiposity and cognitive performance in NWO. We therefore studied the association between cognitive function and body fat percentage (BF%) in NWO, using a representative sample of the United States population. METHODS: A cross-sectional study was performed using the nationwide 1988 to 1994 data set from the Third National Health and Nutrition Examination Survey. Cognitive function was measured by three validated cognitive tests: simple reaction time test (SRTT), symbol digit substitution test (SDST), and serial digit learning test (SDLT). The association between BF% and cognitive performance was evaluated in 2,039 adults aged 20-59 years and with a body mass index ranging from 18.5 to 24.9 kg/m2. Linear regression modeling was used to adjust for potential confounders. RESULTS: Increased BF% was significantly associated with poorer performance on SDLT in the entire study sample (coefficient [95% CI]: 0.15 [0.01, 0.29]) and with poorer performance on SDST in the age group 20-29 years (coefficient [95% CI]: 0.30 [0.10, 0.49]). Increased BF% did not significantly predict poorer performance on SRTT. CONCLUSION: Higher BF% is significantly associated with poorer cognitive function in a nationally representative sample of US adults with NWO. The identification of possible complications associated with increased adipose tissue underlines the need to measure body fat content in NWO individuals, whose metabolic and cognitive dysfunction could go undetected for years due to their young age and normal body weight.

Ghrelin system in alcohol-dependent subjects: role of plasma ghrelin levels in alcohol drinking and craving.

Animal studies suggest that the gut-brain peptide ghrelin plays an important role in the neurobiology of alcohol dependence (AD). Human studies show an effect of alcohol on ghrelin levels and a correlation between ghrelin levels and alcohol craving in alcoholics. This investigation consisted of two studies. Study 1 was a 12-week study with alcohol-dependent subjects, where plasma ghrelin determinations were assessed four times (T0-T3) and related to alcohol intake and craving [Penn Alcohol Craving Score (PACS) and Obsessive Compulsive Drinking Scale (OCDS)]. Serum growth hormone levels and assessment of the nutritional/metabolic status were also performed. Study 2 was a pilot case-control study to assess ghrelin gene polymorphisms (Arg51Gln and Leu72Met) in alcohol-dependent individuals. Study 1 showed no significant differences in ghrelin levels in the whole sample, while there was a statistical difference for ghrelin between non-abstinent and abstinent subjects. Baseline ghrelin levels were significantly and positively correlated with the PACS score at T1 and with all craving scores both at T2 and T3 (PACS, OCDS, obsessive and compulsive OCDS subscores). In Study 2, although there was a higher frequency of the Leu72Met ghrelin gene polymorphism in alcohol-dependent individuals, the distribution between healthy controls and alcohol dependent individuals was not statistically significant. This investigation suggests that ghrelin is potentially able to affect alcohol-seeking behaviors, such as alcohol drinking and craving, representing a new potential neuropharmacological target for AD.

Personalized medicine in diabetes.

BACKGROUND: Multiple genes that are associated with the risk of developing diabetes or the risk of diabetes complications have been identified by candidate gene analysis and genomewide scanning. These molecular markers, together with clinical data and findings from proteomics, metabolomics, pharmacogenetics, and other methods, lead to a consideration of the extent to which personalized approaches can be applied to the treatment of diabetes mellitus. CONTENT: Known genes that cause monogenic subtypes of diabetes are reviewed, and several examples are discussed in which the genotype of an individual with diabetes can direct considerations of preferred choices for glycemic therapy. The extent of characterization of polygenic determinants of type 1 and type 2 diabetes is summarized, and the potential for using this information in personalized management of glycemia and complications in diabetes is discussed. The application and current limitations of proteomic and metabolomic methods in elucidating diabetes heterogeneity is reviewed. SUMMARY: There is established heterogeneity in the determinants of diabetes and the risk of diabetes complications. Understanding the basis of this heterogeneity provides an opportunity for personalizing prevention and treatment strategies according to individual patient clinical and molecular characteristics. There is evidence-based support for benefits from a personalized approach to diabetes care in patients with certain monogenic forms of diabetes. It is anticipated that strategies for individualized treatment decisions in the more common forms of diabetes will emerge with expanding knowledge of polygenic factors and other molecular determinants of disease.

Food fried in extra-virgin olive oil improves postprandial insulin response in obese, insulin-resistant women.

The benefits of low glycemic load (GL) diets on clinical outcome in several metabolic and cardiovascular diseases have extensively been demonstrated. The GL of a meal can be affected by modulating the bioavailability of carbohydrates or by changing food preparation. We investigated the effect on plasma glucose and insulin response in lean and obese women of adding raw or fried extra-virgin olive oil to a carbohydrate-containing meal. After an overnight fast, 12 obese insulin-resistant women (body mass index [BMI], 32.8 ± 2.2 kg/m(2)) and five lean subjects (BMI, 22.2 ± 1.2 kg/m(2)) were randomly assigned to receive two different meals (designated A and B). Meal A was composed of 60 g of pasta made from wheat flour and 150 g of grilled courgettes with 25 g of uncooked oil. Meal B included 15 g of oil in the 150 g of deep-fried courgettes and 10 g of oil in the 60 g of stir-fried pasta. Both meals included 150 g of apple. Blood samples were collected at baseline and every 30 minutes over a 3-hour post-meal period and were tested for levels of glucose, insulin, C-peptide, and triglycerides. The area under the curve (AUC) values were calculated. In obese women the AUCs for C-peptide were significantly higher after meal A than after meal B at 120 minutes (W [Wilcoxon sign rank test] = 27.5, P = .0020), 150 minutes (W = 26.5, P = .0039), and 180 minutes (W = 26.5, P = .0039). No differences were found in lean subjects. This study demonstrated that in obese, insulin-resistant women, food fried in extra-virgin olive oil significantly reduced both insulin and C-peptide responses after a meal.

Increased serum high-density lipoprotein-cholesterol concentration in celiac disease after gluten-free diet treatment correlates with body fat stores.

BACKGROUND: Low high-density lipoprotein-cholesterol (HDL-C) concentration correlates with increased cardiovascular risk. A great prevalence of celiac disease (CD) was reported among patients with low HDL-C concentration, and gluten-free diet (GFD) treatment seems to normalize lipid profile. We evaluated blood lipids and body composition in 26 CD patients with low HDL-C level (<1.0 mmol/L) at diagnosis and after GFD. STUDY: A case-control study. METHODS: The diagnosis was based on histologic evidence of subtotal or total duodenal villous atrophy. Patients were studied before and after GFD treatment (14.2+/-1.4 mo) with biopsy-proven return to normal of the duodenal mucosa. HDL-C was enzymatically assessed after precipitation of very low-density lipoprotein and low-density lipoprotein with heparin-magnesium. Apolipoprotein (Apo)-AI level was assessed by immunoturbidimetric assay; triglycerides by an enzymatic colorimetric method. Body composition was assessed by dual-energy x-ray absorptiometry. RESULTS: Body composition improved after GFD, with increasing body weight (P<0.05) essentially owing to increased fat mass (FM) (P<0.01), rather than fat-free mass (P=0.064). Total cholesterol and HDL-C were lower in untreated compared with treated patients (P<0.001 and P<0.0001). Apo-AI level increased significantly after GFD (1.20+/-0.22 vs. 1.46+/-0.17 g/L; P<0.0001). Apo-AI, sex, and FM were all significant determinants of HDL-C level; a positive correlation (R=0.68; P<0.0001) was found between increase in HDL-C level and in FM after GFD treatment. CONCLUSIONS: Restoration of lipid profile in CD patients after GFD treatment may be explained by an increase in both Apo-AI secretion by intestinal cells and body fat stores.

Is cortisol involved in the alcohol-related fat mass impairment? A longitudinal clinical study.

AIMS: Subjects with chronic alcohol abuse can present several metabolic and nutritional alterations. The hypothalamic-pituitary-adrenal (HPA) axis may play a role in these nutritional and metabolic disorders. The goal of this study was to investigate if there is any relationship between HP-hormones and metabolic and nutritional parameters in alcoholic subjects. METHODS: Sixteen alcoholics were considered before and after 3 months of total alcohol abstinence. HP-related hormones were determined. Nutritional and metabolic parameters were assessed by dual-energy X-ray absorptiometry (DXA) and indirect calorimetry. RESULTS: At baseline, a significant negative correlation was found between fat mass (FM) and cortisol (r = -0.54, P = 0.03). During abstinence, a significant increase of both body mass index (BMI) (P < 0.0001) and FM (P < 0.0001) was found at 12 weeks compared to baseline. A significant decrease of both plasma cortisol (P = 0.044) and aldosterone (P = 0.023) was found at 12 weeks compared to baseline. At 12 weeks, the significant correlation between cortisol and FM disappeared. CONCLUSIONS: A higher HPA-axis activation-reflected by higher cortisol levels-was associated with a lower FM in alcoholics. Conversely, during total abstinence a reduced HPA-axis activity can play a role in the parallel nutritional recovery. The present results suggest a role of the HPA axis throughout cortisol both in the etiology of the alcohol-related nutritional alterations and in their recovery after a period of total alcohol abstinence.

Relationship between the hypothalamic-pituitary-thyroid axis and alcohol craving in alcohol-dependent patients: a longitudinal study.

BACKGROUND: A relationship between some hypothalamic-pituitary-related hormones and craving for alcohol has been suggested, leading to hypothesize a role of some hormones in the neurobiology of alcohol dependence. Investigating this association in alcohol-dependent (AD) patients was the aim of this preliminary and exploratory study. METHODS: Cortisol, adrenocorticotropic hormone, prolactin, thyroid-stimulating hormone (TSH), free T3, free T4, growth hormone, follicle-stimulating hormone, luteinizing hormone as well as administering the Obsessive-Compulsive Drinking Scale (OCDS) and Penn Alcohol Craving Scale (PACS) were assessed at baseline and after 12 weeks in 25 current AD patients. Patients were treated with baclofen (10 mg t.i.d.) for these 12 weeks. Sixteen patients remained totally abstinent for 12 weeks. RESULTS: At baseline, a significant inverse correlation was found between TSH and PACS (r = -0.46; p = 0.022) and OCDS scores (r = -0.53; p = 0.007). A significant direct correlation was found between free T3 and OCDS score (r = 0.44; p = 0.026). In the 16 abstinent patients, craving scores were significantly decreased at 12 weeks (p < 0.01). At 12 weeks, no significant correlation was found between TSH and craving, but free T3 remained directly correlated with OCDS score (r = 0.60; p = 0.013). CONCLUSIONS: A relationship between alcohol craving and free T3 and TSH was demonstrated in AD patients, suggesting the potential involvement of the hypothalamic-pituitary-thyroid axis in the neurobiology of alcohol craving.

Celiac disease: what's new about it?

In the present review we will try to summarize the clinical and diagnostic features of celiac disease (CD) as well as the new findings on extraintestinal manifestation. CD is an immune-mediated enteropathy caused by a permanent gluten intolerance. In the last years, the diagnosis is becoming more and more frequent because of the recognition of 'new' symptoms and associated extraintestinal manifestations. Classical CD is dominated by symptoms and sequelae of gastrointestinal malabsorption. In the 'atypical forms', the extraintestinal features usually predominate, with few or no gastrointestinal symptoms. Silent CD refers to asymptomatic patients with a positive serologic test and villous atrophy on biopsy. This form is detected by screening of high-risk individuals, or villous atrophy occasionally may be detected by endoscopy and biopsy conducted for another reason. The potential form is diagnosed in groups at risk including relatives of celiac patients, Down syndrome and autoimmune diseases. Latent CD is defined by positive serological tests but not histological changes on biopsy. These individuals are asymptomatic, but later may develop symptoms and/or histological alterations. Recognition of atypical manifestations of CD is very important because many cases can remain undiagnosed with an increased risk of long-term complications.

Metabolic and nutritional features in adult celiac patients.

Celiac disease (CD) is a chronic immune-mediated gluten-dependent enteropathy induced by ingestion of gluten-containing products, characterized by intestinal malabsorption and subtotal or total atrophy of intestinal villi, which improves after gluten-free diet (GFD). Untreated patients affected by the classic form of CD are at high risk of malnutrition, but an impairment of nutritional status is frequently reported also in patients with the subclinical form of the disease. Strict adherence to a GFD greatly improves nutritional status, inducing an increase in fat and bone compartments, but does not completely normalize body composition. A lack of improvement in nutritional status may identify incomplete adherence to GFD treatment. Evidence has shown lower body weights and lower fat mass and fat-free mass contents in CD patients. Untreated CD patients oxidize more carbohydrates as energy substrate compared to treated subjects. In addition, circulating ghrelin concentration was reduced after GFD treatment as a possible consequence of body composition improvement, while leptin did not correlate with the changes in body composition and substrate oxidation in patients with CD. A significant correlation was reported between ghrelin and the degree of severity of intestinal mucosal lesions. CD patients might show an alteration in lipid metabolism, i.e. low serum total and high- density lipoprotein-cholesterol as a consequence of lipid malabsorption and decreased intake. In conclusion, weight loss and nutritional deficiencies are relevant clinical features in CD. Thus, an early and accurate evaluation of nutritional status and energy metabolism represents a fundamental tool in the management of CD patients.

Intestinal malabsorption and skin diseases.

Several skin manifestations were described in patients affected by intestinal disorders. The development of skin diseases in these patients could be related to the impairment of intestinal absorption and motility, other than to immunological and hormonal changes. The growing evidence of the association between skin disorders and intestinal diseases suggests that the skin could be considered the 'mirror of the gut'.

Insulin but not insulin growth factor-1 correlates with craving in currently drinking alcohol-dependent patients.

BACKGROUND: Preclinical data suggest that brain insulin and insulin growth factor-1 (IGF-1) may contribute to the development of addiction. The aim of this clinical study was to evaluate the relationships between insulin and IGF-1 plasma concentrations and alcohol craving. METHODS: The correlations between insulin and craving in actively drinking alcoholics were evaluated in the experiment 1 retrospectively and in the experiment 2 in a case-control study. Experiment 3 evaluated the correlations between insulin and craving in 12-weeks abstinent alcoholics in a longitudinal study. C-peptide and IGF-1 were also investigated in experiments 2-3. Alcohol craving was evaluated by the Obsessive-Compulsive Drinking Scale (OCDS). RESULTS: Significant positive correlations between insulin concentrations and craving scores were found in actively drinkers (p < 0.05). Specifically, in the first experiment insulin significantly correlated with the compulsive scores. In the second experiment and in an analysis of experiments 1-2 together, insulin plasma concentration correlated with total OCDS craving (p < 0.05) and compulsive craving (p < 0.05) and showed a trend of correlation with the obsessive craving. At 12 weeks no correlation was found between insulin and craving scores. In all the experiments the correlations between C-peptide and craving were close to the ones between insulin and craving while IGF-1 never correlated with craving. CONCLUSIONS: This study suggests that insulin could be involved in the neurobiology of alcohol craving and addiction. This characteristic seems specific of insulin since similar data were found on C-peptide but not on IGF-1. Future confirming studies on larger samples are needed, also to investigate possible therapeutic implications.

Analysis of the T1288R mutation of the Wilson disease ATP7B gene in four generations of a family: possible genotype-phenotype correlation with hepatic onset.

Wilson disease, an autosomal recessive disorder due to mutations of the ATP7B gene, is characterized by copper accumulation and toxicity in the liver and subsequently in other organs, mainly the brain and cornea. A new missense mutation (T1288R) of the ATP7B gene has recently been discovered in a Wilson disease patient in our laboratory. The aim of the present study was to analyze clinical and genetic features of more generations of the family of the patient in which the new mutation T1288R was discovered. A total of 19 subjects were studied; in particular, four generations of the patient's family were analyzed. The ATP7B gene was analyzed by single-strand conformational polymorphism followed by direct sequencing. Two brothers presented a clinical diagnosis of Wilson disease with an hepatic phenotype and a genotype characterized by the homozygotic mutation T1288R. The heterozygotic mutation T1288R was found in seven subjects belonging to all four generations. The present study represents the first screening for a Wilson disease mutation through four generations of a nonconsanguineous family. All the patients with the homozygotic T1288R mutation in the present pedigree presented an hepatic phenotype without a neurological presentation. Consequently, a genotype-phenotype correlation could be hypothesized, although further studies are necessary to clarify this topic.

Relationship between ghrelin levels, alcohol craving, and nutritional status in current alcoholic patients.

BACKGROUND: Ghrelin is a peptide produced mainly by the gut and hypothalamus. Ghrelin is able to stimulate food-seeking behavior. Alcohol-craving and food-seeking behavior could share common neural circuits. Ghrelin is related to nutritional status, but few data are available in alcoholic patients on the relationship between ghrelin and nutritional disorders. METHODS: Plasma ghrelin was evaluated in 15 current alcoholic male patients compared with 15 healthy male volunteers. Craving was evaluated by the Obsessive-Compulsive Drinking Scale. Body composition was assessed by dual-energy X-ray absorptiometry. Energy substrate utilization was evaluated by indirect calorimetry. RESULTS: Ghrelin was significantly reduced in alcohol-dependent patients with respect to healthy subjects (p=0.0278). A significant positive correlation was found between ghrelin and craving (r=0.55; p=0.034). A preferential utilization of lipids as an energy substrate with a reduction of the fat mass (p=0.01) and an increase of the free fat mass (p=0.0091) was found in alcoholic patients. CONCLUSIONS: Within our sample showing low ghrelin levels probably related to the impaired nutritional status; patients with higher levels of ghrelin showed higher levels of alcohol craving. These preliminary data indicate that ghrelin could be implicated in the neurobiological mechanisms of alcohol craving, other than a hormone influenced by the nutritional status.