Transplantation of porcine adrenal spheroids for the treatment of adrenal insufficiency.

Primary adrenal insufficiency is a life-threatening disorder, which requires lifelong hormone replacement therapy. Transplantation of xenogeneic adrenal cells is a potential alternative approach for the treatment of adrenal insufficiency. For a successful outcome of this replacement therapy, transplanted cells should provide adequate hormone secretion and respond to adrenal physiological stimuli. Here, we describe the generation and characterization of primary porcine adrenal spheroids capable of replacing the function of adrenal glands in vivo. Cells within the spheroids morphologically resembled adult adrenocortical cells and synthesized and secreted adrenal steroid hormones in a regulated manner. Moreover, the embedding of the spheroids in alginate led to the formation of cellular elongations of steroidogenic cells migrating centripetally towards the inner part of the slab, similar to zona Fasciculata cells in the intact organ. Finally, transplantation of adrenal spheroids in adrenalectomized SCID mice reversed the adrenal insufficiency phenotype, which significantly improved animals' survival. Overall, such adrenal models could be employed for disease modeling and drug testing, and represent the first step toward potential clinical trials in the future.

Fructose- and sucrose- but not glucose-sweetened beverages promote hepatic de novo lipogenesis: A randomized controlled trial.

BACKGROUND & AIMS: Excessive fructose intake is associated with increased de novo lipogenesis, blood triglycerides, and hepatic insulin resistance. We aimed to determine whether fructose elicits specific effects on lipid metabolism independently of excessive caloric intake. METHODS: A total of 94 healthy men were studied in this double-blind, randomized trial. They were assigned to daily consumption of sugar-sweetened beverages (SSBs) containing moderate amounts of fructose, sucrose (fructose-glucose disaccharide) or glucose (80 g/day) in addition to their usual diet or SSB abstinence (control group) for 7 weeks. De novo fatty acid (FA) and triglyceride synthesis, lipolysis and plasma free FA (FFA) oxidation were assessed by tracer methodology. RESULTS: Daily intake of beverages sweetened with free fructose and fructose combined with glucose (sucrose) led to a 2-fold increase in basal hepatic fractional secretion rates (FSR) compared to control (median FSR %/day: sucrose 20.8 (p = 0.0015); fructose 19.7 (p = 0.013); control 9.1). Conversely, the same amounts of glucose did not change FSR (median of FSR %/day 11.0 (n.s.)). Fructose intake did not change basal secretion of newly synthesized VLDL-triglyceride, nor did it alter rates of peripheral lipolysis, nor total FA and plasma FFA oxidation. Total energy intake was similar across groups. CONCLUSIONS: Regular consumption of both fructose- and sucrose-sweetened beverages in moderate doses - associated with stable caloric intake - increases hepatic FA synthesis even in a basal state; this effect is not observed after glucose consumption. These findings provide evidence of an adaptative response to regular fructose exposure in the liver. LAY SUMMARY: This study investigated the metabolic effects of daily sugar-sweetened beverage consumption for several weeks in healthy lean men. It revealed that beverages sweetened with the sugars fructose and sucrose (glucose and fructose combined), but not glucose, increase the ability of the liver to produce lipids. This change may pave the way for further unfavorable effects on metabolic health. CLINICAL TRIAL REGISTRATION NUMBER: NCT01733563.

Glycemic control and complications in glycogen storage disease type I: Results from the Swiss registry.

BACKGROUND: Regular carbohydrate intake to avoid hypoglycemia is the mainstay of dietary treatment in glycogen storage disease type I (GSDI). The aim of this study was to evaluate the quality of dietary treatment and glycemic control in a cohort of GSDI patients, in relation to the presence of typical long-term complications. METHODS: Data of 25 patients (22 GSD subtype Ia and 3 GSDIb, median age 20y) from the Swiss hepatic glycogen storage disease registry was analyzed cross-sectionally. Frequency and type of hypoglycemia symptoms were assessed prospectively using a structured questionnaire. Diagnostic continuous glucose monitoring (CGM) was performed as part of usual clinical care to assess glycemic control in 14 patients, usually once per year with a mean duration of 6.2 ±â€¯1.1 consecutive days per patient per measurement. RESULTS: Although maintenance of euglycemia is the primary goal of dietary treatment, few patients (n = 3, 13%) performed capillary blood glucose measurements regularly. Symptoms possibly associated with hypoglycemia were present in 13 patients (57%), but CGM revealed periods of low glucose (<4 mmol/l) in all patients, irrespective of the presence of symptoms. GSDIa patients with liver adenomas (n = 9, 41%) showed a higher frequency and area under the curve (AUC) of low blood glucose than patients without adenomas (frequency 2.7 ±â€¯0.8 vs. 1.5 ±â€¯0.7 per day, AUC 0.11 ±â€¯0.08 vs. 0.03 ±â€¯0.02 mmol/l/d; p < 0.05). Similarly, the presence of microalbuminuria was also associated with the frequency of low blood glucose. Z-Scores of bone density correlated negatively with lactate levels. CONCLUSION: The quality of glucose control is related to the presence of typical long-term complications in GSDI. Many patients experience episodes of asymptomatic low blood glucose. Regular assessment of glucose control is an essential element to evaluate the quality of treatment, and increasing the frequency of glucose self-monitoring remains an important goal of patient education and motivation. CGM devices may support patients to optimize dietary therapy in everyday life.

Islet transplantation as safe and efficacious method to restore glycemic control and to avoid severe hypoglycemia after donor organ failure in pancreas transplantation.

The aim of this study was to assess safety and efficacy of islet transplantation after initial pancreas transplantation with subsequent organ failure. Patients undergoing islet transplantation at our institution after pancreas organ failure were compared to a control group of patients with pancreas graft failure, but without islet transplantation and to a group receiving pancreas retransplantation. Ten patients underwent islet transplantation after initial pancreas transplantation failed and were followed for a median of 51 months. The primary end point of HbA1c <7.0% and freedom of severe hypoglycemia was met by nine of 10 patients after follow-up after islet transplantation and in all three patients in the pancreas retransplantation group, but by none of the patients in the group without retransplantation (n = 7). Insulin requirement was reduced by 50% after islet transplantation. Kidney function (eGFR) declined with a rate of -1.0 mL ± 1.2 mL/min/1.73 m2 per year during follow-up after islet transplantation, which tended to be slower than in the group without retransplantation (P = .07). Islet transplantation after deceased donor pancreas transplant failure is a method that can safely improve glycemic control and reduce the incidence of severe hypoglycemia and thus establish similar glycemic control as after initial pancreas transplantation, despite the need of additional exogenous insulin.

Specific and redundant roles of PKBα/AKT1 and PKBß/AKT2 in human pancreatic islets.

Protein kinase Bα (PKBα)/AKT1 and PKBß/AKT2 are required for normal peripheral insulin action but their role in pancreatic ß cells remains enigmatic as indicated by the relatively mild islet phenotype of mice with deficiency for either one of these two isoforms. In this study we have analysed proliferation, apoptosis, ß cell size and glucose-stimulated insulin secretion in human islets overexpressing either PKBα or PKBß. Our results reveal redundant and specific functions. Overexpression of either isoform resulted in increased ß cell size, but insulin production and secretion remained unchanged. Proliferation and apoptosis of ß cells were only significantly stimulated and inhibited, respectively, by PKBα/AKT1. Importantly, overexpression of PKBα/AKT1 in dissociated islets increased the ratio of ß cells to non-ß cells. These results confirm our previous findings obtained with rodent islets and strongly indicate that PKBα/AKT1 can regulate ß cell mass also in human islets.

Reduced hepatic lipid content in Pten-haplodeficient mice because of enhanced AKT2/PKBß activation in skeletal muscle.

BACKGROUND & AIMS: Non-alcoholic fatty liver disease (NAFLD) is a major health problem and occurs frequently in the context of metabolic syndrome and type 2 diabetes mellitus. Hepatocyte-specific Pten-deficiency in mice was shown previously to result in hepatic steatosis due to hyperactivated AKT2. However, the role of peripheral insulin-sensitive tissues on PTEN- and AKT2-dependent accumulation of hepatic lipids has not been addressed. METHODS: Effects of systemically perturbed PTEN/AKT2 signalling on hepatic lipid content were studied in Pten-haplodeficient (Pten(+/-) /Akt2(+/+) ) mice and Pten-haplodeficient mice lacking Akt2 (Pten(+/-) /Akt2(-/-) ). The liver and skeletal muscle were characterized by histology and/or analysis of insulin signalling. To assess the effects of AKT2 activity in skeletal muscle on hepatic lipid content, AKT2 mutants were expressed in skeletal muscle of Pten(+/+) /Akt2(+/+) and Pten(+/-) /Akt2(+/+) mice using adeno-associated virus 8. RESULTS: Pten(+/-) /Akt2(+/+) mice were found to have a more than 2-fold reduction in hepatic lipid content, at a level similar to that observed in Pten(+/-) /Akt2(-/-) mice. Insulin signalling in the livers of Pten(+/-) /Akt2(+/+) mice was enhanced, indicating that extrahepatic factors prevent lipid accumulation. The skeletal muscle of Pten(+/-) /Akt2(+/+) mice also showed enhanced insulin signalling. Skeletal muscle-specific expression of constitutively active AKT2 reduced hepatic lipid content in Pten(+/+) /Akt2(+/+) mice, and dominant negative AKT2 led to an increase in accumulation of hepatic lipids in both Pten(+/+) /Akt2(+/+) and Pten(+/-) /Akt2(+/+) mice. CONCLUSION: Our results demonstrate that AKT2 activity in skeletal muscle critically affects lipid accumulation in the livers of Pten(+/+) /Akt2(+/+) and Pten(+/-) /Akt2(+/+) mice, and emphasize the role of skeletal muscle in the pathology of NAFLD.

Basal insulin glargine and microvascular outcomes in dysglycaemic individuals: results of the Outcome Reduction with an Initial Glargine Intervention (ORIGIN) trial.

AIMS/HYPOTHESIS: As glycaemia and the incidence of microvascular diabetes complications follow a log-linear relationship, it becomes increasingly difficult to demonstrate a microvascular benefit of glucose-lowering when the HbA1c level is close to normal. METHODS: The Outcome Reduction with an Initial Glargine Intervention (ORIGIN) trial randomised 12,537 people with diabetes, impaired glucose tolerance or impaired fasting glucose to receive standard glycaemic care or standard care with the addition of basal insulin glargine (A21Gly,B31Arg,B32Arg human insulin), targeting a fasting plasma glucose level ≤5.3 mmol/l. Microvascular outcomes during a median follow-up of 6.2 years were examined in participants whose baseline HbA1c was above or below the median of 6.4% (46.4 mmol/mol). RESULTS: Allocation to the insulin glargine group reduced the incidence of the primary microvascular composite outcome of kidney and eye disease in participants whose baseline HbA1c level was ≥6.4% (46.4 mmol/mol; HR 0.90 [95% CI 0.81, 0.99]) but not in participants with a lower baseline HbA1c (HR 1.07 [95% CI 0.95, 1.20]; p value for interaction 0.031). In people whose baseline HbA1c level was ≥6.4% (46.4 mmol/mol), the median post-randomisation change in HbA1c was -0.65% (interquartile range -0.16, -0.91%) after allocation to insulin glargine and -0.33% (-0.83, 0.13%) after allocation to standard care (median HbA1c difference 0.33%; p < 0.0001). A smaller median difference of 0.22% was noted in people whose baseline HbA1c was <6.4% (p < 0.0001). CONCLUSIONS/INTERPRETATION: In patients with dysglycaemia, intervention targeting normal fasting glucose levels reduced HbA1c and attenuated the risk of microvascular outcomes in participants with a baseline HbA1c level ≥6.4% (46.4 mmol/mol). A neutral effect was seen in those with a lower baseline HbA1c level. TRIAL REGISTRATION: ClinicalTrials.gov NCT00069784.

Exploring Medical Career Choice to Better Inform Swiss Physician Workforce Planning: Protocol for a National Cohort Study.

BACKGROUND: A medical student's career choice directly influences the physician workforce shortage and the misdistribution of resources. First, individual and contextual factors related to career choice have been evaluated separately, but their interaction over time is unclear. Second, actual career choice, reasons for this choice, and the influence of national political strategies are currently unknown in Switzerland. OBJECTIVE: The overall objective of this study is to better understand the process of Swiss medical students' career choice and to predict this choice. Our specific aims will be to examine the predominately static (ie, sociodemographic and personality traits) and predominately dynamic (ie, learning context perceptions, anxiety state, motivation, and motives for career choice) variables that predict the career choice of Swiss medical school students, as well as their interaction, and to examine the evolution of Swiss medical students' career choice and their ultimate career path, including an international comparison with French medical students. METHODS: The Swiss Medical Career Choice study is a national, multi-institution, and longitudinal study in which all medical students at all medical schools in Switzerland are eligible to participate. Data will be collected over 4 years for 4 cohorts of medical students using questionnaires in years 4 and 6. We will perform a follow-up during postgraduate training year 2 for medical graduates between 2018 and 2022. We will compare the different Swiss medical schools and a French medical school (the University of Strasbourg Faculty of Medicine). We will also examine the effect of new medical master's programs in terms of career choice and location of practice. For aim 2, in collaboration with the Swiss Institute for Medical Education, we will implement a national career choice tracking system and identify the final career choice of 2 cohorts of medical students who graduated from 4 Swiss medical schools from 2010 to 2012. We will also develop a model to predict their final career choice. Data analysis will be conducted using inferential statistics, and machine learning approaches will be used to refine the predictive model. RESULTS: This study was funded by the Swiss National Science Foundation in January 2023. Recruitment began in May 2023. Data analysis will begin after the completion of the first cohort data collection. CONCLUSIONS: Our research will inform national stakeholders and medical schools on the prediction of students' future career choice and on key aspects of physician workforce planning. We will identify targeted actions that may be implemented during medical school and may ultimately influence career choice and encourage the correct number of physicians in the right specialties to fulfill the needs of currently underserved regions. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/53138.

Mechanisms and clinical relevance of the bidirectional relationship of viral infections with metabolic diseases.

Viruses have been present during all evolutionary steps on earth and have had a major effect on human history. Viral infections are still among the leading causes of death. Another public health concern is the increase of non-communicable metabolic diseases in the last four decades. In this Review, we revisit the scientific evidence supporting the presence of a strong bidirectional feedback loop between several viral infections and metabolic diseases. We discuss how viruses might lead to the development or progression of metabolic diseases and conversely, how metabolic diseases might increase the severity of a viral infection. Furthermore, we discuss the clinical relevance of the current evidence on the relationship between viral infections and metabolic disease and the present and future challenges that should be addressed by the scientific community and health authorities.

Comprehensive description of the N-glycoproteome of mouse pancreatic ß-cells and human islets.

Cell surface N-glycoproteins provide a key interface of cells to their environment and therapeutic entry points for drug and biomarker discovery. Their comprehensive description denotes therefore a formidable challenge. The ß-cells of the pancreas play a crucial role in blood glucose homeostasis, and disruption of their function contributes to diabetes. By combining cell surface and whole cell capturing technologies with high-throughput quantitative proteomic analysis, we report on the identification of a total of 956 unique N-glycoproteins from mouse MIN6 ß-cells and human islets. Three-hundred-forty-nine of these proteins encompass potential surface N-glycoproteins and include orphan G-protein-coupled receptors, novel proteases, receptor protein kinases, and phosphatases. Interestingly, stimulation of MIN6 ß-cells with glucose and the hormone GLP1, known stimulators of insulin secretion, causes significant changes in surface N-glycoproteome expression. Taken together, this ß-cell N-glycoproteome resource provides a comprehensive view on the composition of ß-cell surface proteins and expands the scope of signaling systems potentially involved in mediating responses of ß-cells to various forms of (patho)physiologic stress and the extent of dynamic remodeling of surface N-glycoprotein expression associated with metabolic and hormonal stimulation. Moreover, it provides a foundation for the development of diabetes medicines that target or are derived from the ß-cell surface N-glycoproteome.

Do Sugar-Sweetened Beverages Increase Fasting FGF21 Irrespective of the Type of Added Sugar? A Secondary Exploratory Analysis of a Randomized Controlled Trial.

Human fibroblast growth factor 21 (FGF21) is a multifaceted metabolic regulator considered to control sugar intake and to exert beneficial effects on glucose and lipid metabolism. Elevated serum FGF21 levels are associated with metabolic syndrome, suggesting a state of FGF21 resistance. Further, given the evidence of a hepatic ChREBP and FGF21 signaling axis, it can be assumed that SSBs containing fructose would possibly increase FGF21 concentrations. We investigated the effects of sugar-sweetened beverage (SSB) consumption on fasting FGF21 levels in healthy, lean men, discriminating the effects of glucose, fructose, and their disaccharide sucrose by secondary data analysis from a randomized controlled trial. Seven weeks of daily SSB consumption resulted in increased fasting FGF21 in healthy, lean men, irrespective of the sugar type. Medians of ΔFGF21 between post-SSB intervention values (week 7) and no-intervention period values (IQR) in pg/mL were: glucose 17.4 (0.4-45.8), fructose 22.9 (-8.6-35.1), and sucrose 13.7 (2.2-46.1). In contrast, this change in FGF21 concentration was only 6.3 (-20.1-26.9) pg/mL in the control group. The lack of a fructose-specific effect on FGF21 concentrations is contrary to our assumption. It is concluded that SSB intake may impact FGF21 concentrations and could contribute to the increased FGF21 concentrations observed in subjects suffering from metabolic syndrome that is possibly associated with decreased FGF21 responsiveness.

Lack of ZnT8 protects pancreatic islets from hypoxia- and cytokine-induced cell death.

Pancreatic ß-cells depend on the well-balanced regulation of cytosolic zinc concentrations, providing sufficient zinc ions for the processing and storage of insulin, but avoiding toxic effects. The zinc transporter ZnT8, encoded by SLC30A8,is a key player regarding islet cell zinc homeostasis, and polymorphisms in this gene are associated with altered type 2 diabetes susceptibility in man. The objective of this study was to investigate the role of ZnT8 and zinc in situations of cellular stress as hypoxia or inflammation. Isolated islets of WT and global ZnT8-/- mice were exposed to hypoxia or cytokines and cell death was measured. To explore the role of changing intracellular Zn2+ concentrations, WT islets were exposed to different zinc concentrations using zinc chloride or the zinc chelator N,N,N',N'-tetrakis(2-pyridinylmethyl)-1,2-ethanediamine (TPEN). Hypoxia or cytokine (TNF-α, IFN-γ, IL1-ß) treatment induced islet cell death, but to a lesser extent in islets from ZnT8-/- mice, which were shown to have a reduced zinc content. Similarly, chelation of zinc with TPEN reduced cell death in WT islets treated with hypoxia or cytokines, whereas increased zinc concentrations aggravated the effects of these stressors. This study demonstrates a reduced rate of cell death in islets from ZnT8-/- mice as compared to WT islets when exposed to two distinct cellular stressors, hypoxia or cytotoxic cytokines. This protection from cell death is, in part, mediated by a reduced zinc content in islet cells of ZnT8-/- mice. These findings may be relevant for altered diabetes burden in carriers of risk SLC30A8 alleles in man.

Ezetimibe alone or in combination with simvastatin increases small dense low-density lipoproteins in healthy men: a randomized trial.

AIMS: The predominance of small dense low-density lipoproteins (sdLDLs) has been associated with increased cardiovascular risk. The effect of ezetimibe on LDL subfraction distribution has not been fully elucidated. This study assessed by gradient gel electrophoresis the effects of ezetimibe alone, simvastatin alone, and their combination on sdLDL subfraction distribution. METHODS AND RESULTS: A single-centre, randomized, parallel three-group open-label study was performed in 72 healthy men with a baseline LDL-cholesterol (LDL-C) concentration of 111 +/- 30 mg/dL (2.9 +/- 0.8 mmol/L). They were treated with ezetimibe (10 mg/day, n = 24), simvastatin (40 mg/day, n = 24), or their combination (n = 24) for 14 days. Blood was drawn before and after the treatment period. Generalized estimating equations were used to assess the influence of drug therapy on LDL subfraction distribution, controlling for within-subject patterns (clustering). We adjusted for age, body mass index, and baseline concentrations of LDL-C and triglycerides. Ezetimibe alone changed LDL subfraction distribution towards a more atherogenic profile by significantly increasing sdLDL subfractions (LDL-IVA +14.2%, P = 0.0216 and LDL-IVB +16.7%, P = 0.039; fully adjusted Wald chi(2) test). In contrast, simvastatin alone significantly decreased the LDL-IVB subfraction (-16.7%, P = 0.002). This effect was offset when simvastatin was combined with ezetimibe (LDL-IVB +14.3%, P = 0.44). All three treatments decreased the large, more buoyant LDL-I subfraction, the effects of ezetimibe being the most pronounced (ezetimibe -13.9%, P < 0.0001; combination therapy -7.3%, P = 0.0743; simvastatin -4.6%, P < 0.0001). CONCLUSION: In healthy men, treatment with ezetimibe alone is associated with the development of a pro-atherogenic LDL subfraction profile. Potentially atheroprotective effects of simvastatin are offset by ezetimibe. This study is registered with ClinicalTrials.gov, identifier no. NCT00317993.

COVID-19 and metabolic disease: mechanisms and clinical management.

Up to 50% of the people who have died from COVID-19 had metabolic and vascular disorders. Notably, there are many direct links between COVID-19 and the metabolic and endocrine systems. Thus, not only are patients with metabolic dysfunction (eg, obesity, hypertension, non-alcoholic fatty liver disease, and diabetes) at an increased risk of developing severe COVID-19 but also infection with SARS-CoV-2 might lead to new-onset diabetes or aggravation of pre-existing metabolic disorders. In this Review, we provide an update on the mechanisms of how metabolic and endocrine disorders might predispose patients to develop severe COVID-19. Additionally, we update the practical recommendations and management of patients with COVID-19 and post-pandemic. Furthermore, we summarise new treatment options for patients with both COVID-19 and diabetes, and highlight current challenges in clinical management.

The Diabetes Gene JAZF1 Is Essential for the Homeostatic Control of Ribosome Biogenesis and Function in Metabolic Stress.

The ability of pancreatic ß-cells to respond to increased demands for insulin during metabolic stress critically depends on proper ribosome homeostasis and function. Excessive and long-lasting stimulation of insulin secretion can elicit endoplasmic reticulum (ER) stress, unfolded protein response, and ß-cell apoptosis. Here we show that the diabetes susceptibility gene JAZF1 is a key transcriptional regulator of ribosome biogenesis, global protein, and insulin translation. JAZF1 is excluded from the nucleus, and its expression levels are reduced upon metabolic stress and in diabetes. Genetic deletion of Jazf1 results in global impairment of protein synthesis that is mediated by defects in ribosomal protein synthesis, ribosomal RNA processing, and aminoacyl-synthetase expression, thereby inducing ER stress and increasing ß-cell susceptibility to apoptosis. Importantly, JAZF1 function and its pleiotropic actions are impaired in islets of murine T2D and in human islets exposed to metabolic stress. Our study identifies JAZF1 as a central mediator of metabolic stress in ß-cells.

Small, dense low-density lipoproteins (LDL) are predictors of cardio- and cerebro-vascular events in subjects with the metabolic syndrome.

OBJECTIVE: Small, dense low-density lipoproteins (LDL) are a feature of the metabolic syndrome (MS) but their predictive role still remains to be established. We performed a 2-year follow-up study in 124 subjects with MS (63 +/- 6 years), as defined by the American Heart Association/National Heart, Lung and Blood Institute guidelines, to assess clinical and biochemical predictors of cerebro- and cardio-vascular events. METHODS AND RESULTS: Beyond traditional cardiovascular risk factors, we measured LDL size and subclasses by gradient gel electrophoresis. Clinical events were registered in the 25% of subjects. At univariate analysis subjects with events had increased prevalence of elevated fasting glucose (P = 0.0117), smoking (P = 0.0015), family history of coronary artery disease (P = 0.0033) and higher levels of total- and LDL-cholesterol (P = 0.0027 and P = 0.0023, respectively); LDL size was lower (P < 0.0001), due to reduced larger subclasses and increased small, dense LDL (all P < 0.0001). At multivariate analysis the following were independent predictors of events (univariate odd ratios were calculated): low HDL-cholesterol (OR 15.4, P = 0.0238), elevated fasting glucose (OR 12.1, P = 0.0102), elevated small, dense LDL (OR 11.7, P = 0.0004), elevated blood pressure (OR 9.2, P = 0.0392), smoking (OR 4.8, P = 0.0054). CONCLUSIONS: This is the first study that assessed the predictive role of small, dense LDL beyond traditional cardiovascular risk factors in subjects with MS.

Milder forms of atherogenic dyslipidemia in ovulatory versus anovulatory polycystic ovary syndrome phenotype.

BACKGROUND: Dyslipidemia is common in women with polycystic ovary syndrome (PCOS) but its prevalence in different PCOS phenotypes is still largely unknown. METHODS: We measured plasma lipids and lipoproteins in 35 anovulatory PCOS (age: 25 +/- 6 years, BMI: 28 +/- 6 kg/m(2)), 15 ovulatory PCOS (age: 30 +/- 6 years, BMI: 25 +/- 3 kg/m(2)) and 27 healthy women (controls) age- and BMI-matched with ovulatory PCOS. PCOS was diagnosed by the presence of clinical or biologic hyperandrogenism associated with chronic anovulation and/or polycystic ovaries at ultrasound. In women with normal menses chronic anovulation was indicated by low serum progesterone levels (<9.54 nmol/l) during midluteal phase (days 21-24) in two consecutive menstrual cycles. RESULTS: Total cholesterol, triglycerides and low-density lipoprotein (LDL)-cholesterol levels increased and high-density lipoprotein (HDL)-cholesterol decreased from controls to ovulatory and then to anovulatory PCOS (all P < 0.05). Levels of lipoprotein(a) (Lp(a)) and small, dense LDL increased (P < 0.0001 for both) and LDL size reduced (P < 0.005) between groups. Insulin resistance (by HOMA) showed a positive correlation with triglycerides and small, dense LDL and an inverse correlation with HDL-cholesterol and LDL size (P < 0.05 for all) in both PCOS phenotypes. No significant correlations were found with testosterone levels. At multivariate analysis, insulin resistance was independently associated with HDL-cholesterol and small, dense LDL in both PCOS phenotypes and with triglyceride concentrations in ovulatory PCOS only. CONCLUSIONS: Women with ovulatory PCOS showed milder forms of atherogenic dyslipidemia than anovulatory PCOS and this seemed to be related to the extent of insulin resistance. Future prospective studies are needed to assess the relative contribution of such alterations on cardiovascular risk.

Diet determines features of the metabolic syndrome in 6- to 14-year-old children.

BACKGROUND/OBJECTIVES: Insulin resistance (IR) and hypertension are common in overweight children, and the adipocyte-derived hormones resistin, adiponectin, and leptin may modulate IR and blood pressure (BP). Few data exist in children on dietary determinants of IR, BP, or leptin, and no data exist on dietary determinants of resistin and adiponectin. Therefore, the objective of this study was to investigate dietary determinants of IR, BP, resistin, adiponectin, and leptin concentrations, as well as the interrelationship among these variables, in normal and overweight children. SUBJECTS/METHODS: In 6- to 14-year-old Swiss children (n=79), nutritional intake was assessed using two 24-hour-recalls and a one-day dietary record. Body mass index (BMI), body fat percentage (BF%), waist/hip ratio (W/H ratio), BP, glucose, insulin, resistin, adiponectin, and leptin were determined. IR was calculated using the quantitative insulin sensitivity check index (QUICKI). RESULTS: BMI, BF%, and W/H ratio were significant predictors of leptin and insulin, QUICKI, and systolic BP, but not resistin or adiponectin. Of the overweight and obese children, 40% were diagnosed pre-hypertensive or hypertensive. Total energy, fat, saturated fat, and protein intakes were significant predictors of fasting insulin and QUICKI, and total fat, saturated fat, and monounsaturated fat intakes were significant predictors of systolic BP, independent of BMI standard deviation score (BMI-SDS) and age. There were no associations between these dietary factors and leptin, adiponectin, or resistin. CONCLUSION: In children, dietary macronutrient composition is a predictor of IR and systolic BP, but not resistin, adiponectin, or leptin concentrations. Resistin and adiponectin concentrations are not correlated with IR or BP in this age range.

Glucose-stimulated insulin production in mice deficient for the PAS kinase PASKIN.

The Per-ARNT-Sim (PAS) domain serine/threonine kinase PASKIN, or PAS kinase, links energy flux and protein synthesis in yeast and regulates glycogen synthase in mammals. A recent report suggested that PASKIN mRNA, protein, and kinase activity are increased in pancreatic islet beta-cells under hyperglycemic conditions and that PASKIN is necessary for insulin gene expression. We previously generated Paskin knockout mice by targeted replacement of the kinase domain with the beta-geo fusion gene encoding beta-galactosidase reporter activity. Here we show that no 5-bromo-4-chloro-3-indolyl-ss-d-galactopyranoside (X-gal) staining was observed in islet beta-cells derived from Paskin knockout mice, irrespective of the ambient glucose concentration, whereas adenoviral expression of the lacZ gene in beta-cells showed strong X-gal staining. No induction of PASKIN mRNA could be detected in insulinoma cell lines or in islet beta-cells. Increasing glucose concentrations resulted in PASKIN-independent induction of insulin mRNA levels and insulin release. PASKIN mRNA levels were high in testes but undetectable in pancreas and in islet beta-cells. Finally, blood glucose levels and glucose tolerance after intraperitoneal glucose injection were indistinguishable between Paskin wild-type and knockout mice. These results suggest that Paskin gene expression is not induced by glucose in pancreatic beta-cells and that glucose-stimulated insulin production is independent of PASKIN.

Superiority of small islets in human islet transplantation.

Many factors influence the outcome of islet transplantation. As islets in the early posttransplant setting are supplied with oxygen by diffusion only and are in a hypoxic state in the portal system, we tested whether small human islets are superior to large islets both in vitro and in vivo. We assessed insulin secretion of large and small islets and quantified cell death during hypoxic conditions simulating the intraportal transplant environment. In the clinical setting, we analyzed the influence of transplanted islet size on insulin production in patients with type 1 diabetes. Our results provide evidence that small islets are superior to large islets with regard to in vitro insulin secretion and show a higher survival rate during both normoxic and hypoxic culture. Islet volume after 48 h of hypoxic culture decreased to 25% compared with normoxic culture at 24 h due to a preferential loss of large islets. In human islet transplantation, the isolation index (islet volume as expressed in islet equivalents/islet number), or more simply the islet number, proved to be more reliable to predict stimulated C-peptide response compared with islet volume. Thus, islet size seems to be a key factor determining human islet transplantation outcome.