Stem Cell Educator therapy in type 1 diabetes: From the bench to clinical trials.

Type 1 diabetes (T1D) is an autoimmune disease that causes a deficit of pancreatic islet ß cells. Millions of individuals worldwide have T1D, and its incidence increases annually. Recent clinical trials have highlighted the limits of conventional immunotherapy in T1D and underscore the need for novel treatments that not only overcome multiple immune dysfunctions, but also help restore islet ß-cell function. To address these two key issues, we have developed a unique and novel procedure designated the Stem Cell Educator therapy, based on the immune education by cord-blood-derived multipotent stem cells (CB-SC). Over the last 10 years, this technology has been evaluated through international multi-center clinical studies, which have demonstrated its clinical safety and efficacy in T1D and other autoimmune diseases. Mechanistic studies revealed that Educator therapy could fundamentally correct the autoimmunity and induce immune tolerance through multiple molecular and cellular mechanisms such as the expression of a master transcription factor autoimmune regulator (AIRE) in CB-SC for T-cell modulation, an expression of Galectin-9 on CB-SC to suppress activated B cells, and secretion of CB-SC-derived exosomes to polarize human blood monocytes/macrophages into type 2 macrophages. Educator therapy is the leading immunotherapy to date to safely and efficiently correct autoimmunity and restore ß cell function in T1D patients.

Perspectives of Health-Care Providers Toward Advance Care Planning in Patients With Advanced Cancer and Congestive Heart Failure.

BACKGROUND: Advance care planning (ACP) discussions afford patients and physicians a chance to better understand patients' values and wishes regarding end-of-life care; however, these conversations typically take place late in the course of a disease. The goal of this study was to clarify attitudes of oncologists, cardiologists, and primary care physicians (PCPs) toward ACP and to identify persistent barriers to timely ACP discussion following a quality improvement initiative at our health system geared at improvement in ACP implementation. METHODS: A 20-question, cross-sectional online survey was created and distributed to cardiologists, oncologists, PCPs, and cardiology and oncology support staff at the NorthShore University HealthSystem (NorthShore) from February to March 2015. A total of 117 individuals (46% of distributed) completed the surveys. The results were compiled using an online survey analysis tool (SurveyMonkey, Inc., Palo Alto, California, USA). RESULTS: Only 15% of cardiologists felt it was their responsibility to conduct ACP discussions with their patients having congestive heart failure (CHF). In contrast, 68% of oncologists accepted this discussion as their responsibility in patients with terminal cancer ( P < .01). These views were mirrored by PCPs, as 68% of PCPs felt personally responsible for ACP discussion with patients having CHF, while only 34% felt the same about patients with cancer. Reported documentation of these discussions in the electronic health record was inconsistent between specialties. Among all surveyed specialties, lack of time was the major barrier limiting ACP discussion. Perceived patient discomfort and discomfort of the patient's family toward these discussions were also significant reported barriers. CONCLUSION: Attitudes toward ACP implementation vary considerably by medical specialty and medical condition, with oncologists in this study tending to feel more personal responsibility for these discussions with patients having cancer than cardiologists with their patients having heart failure. Robust implementation of ACP across the spectrum of medical diagnoses is likely to require a true collaboration between office-based PCPs and specialists in both the inpatient and the ambulatory settings.

Metabolic dysfunction in obese Hispanic women with polycystic ovary syndrome.

STUDY QUESTION: Are certain ethnic groups with polycystic ovary syndrome (PCOS) at increased risk of metabolic disorders? SUMMARY ANSWER: Obese Hispanic women with PCOS are at increased risk of metabolic disorders compared with age- and BMI-matched obese non-Hispanic white women with PCOS in the USA. WHAT IS KNOWN ALREADY: Ethnic differences in body composition and metabolic risk are well established. PCOS is a common disorder in women of reproductive age and is associated with high rates of insulin resistance, glucose intolerance and dyslipidemia. STUDY DESIGN, SIZE, DURATION: A cross-sectional observational study was performed at an Academic Medical Center on 60 women of reproductive age with PCOS. PARTICIPANTS/MATERIALS, SETTING, METHODS: Blood was obtained after fasting from 17 Hispanic, 22 non-Hispanic black and 21 non-Hispanic white women with PCOS who were similar in age and BMI. Anthropometric parameters, insulin, lipid and lipoprotein levels (measured by nuclear magnetic resonance) were compared between the three groups. MAIN RESULTS AND THE ROLE OF CHANCE: Age and BMI did not differ between the groups. Hispanic women with PCOS had higher waist-to-hip ratio (WHR) (P = 0.02), homeostasis model assessment of insulin resistance (HOMA-IR) (P = 0.03) and a more atherogenic lipid and lipoprotein profile consisting of lower high-density lipoprotein (HDL) (P = 0.02), higher low-density lipoprotein (LDL) particle number (P = 0.02), higher very low-density lipoprotein particle (VLDL) size (P = 0.03) and lower LDL (P = 0.03) and HDL particle size (P = 0.005) compared with non-Hispanic white women. The differences in HDL, HOMA-IR, VLDL and LDL size did not persist after adjustment for WHR while differences in LDL particle number (P = 0.04) and HDL size (P = 0.01) persisted. LIMITATIONS, REASON FOR CAUTION: The sample size for the three groups was small but the findings were still significant. The women were mostly obese so the ethnic differences in metabolic disorders may not apply to non-obese women with PCOS. WIDER IMPLICATIONS OF THE FINDINGS: Independent of BMI, obese, reproductive age, Hispanic women with PCOS in the USA had a greater degree of abdominal obesity, insulin resistance and dyslipidemia. Hispanic women with PCOS may benefit from more focused management of metabolic parameters. STUDY FUNDING/COMPETING INTERESTS: This project was supported by the following National Institutes of Health grants: K23 DK080988-01A1 to S.S. and UL1RR029879 to CTSA at University of Illinois. None of the authors report any conflict of interests.

Selective suppression of adipose tissue apoE expression impacts systemic metabolic phenotype and adipose tissue inflammation.

apoE is a multi-functional protein expressed in several cell types and in several organs. It is highly expressed in adipose tissue, where it is important for modulating adipocyte lipid flux and gene expression in isolated adipocytes. In order to investigate a potential systemic role for apoE that is produced in adipose tissue, mice were generated with selective suppression of adipose tissue apoE expression and normal circulating apoE levels. These mice had less adipose tissue with smaller adipocytes containing fewer lipids, but no change in adipocyte number compared with control mice. Adipocyte TG synthesis in the presence of apoE-containing VLDL was markedly impaired. Adipocyte caveolin and leptin gene expression were reduced, but adiponectin, PGC-1, and CPT-1 gene expression were increased. Mice with selective suppression of adipose tissue apoE had lower fasting lipid, insulin, and glucose levels, and glucose and insulin tolerance tests were consistent with increased insulin sensitivity. Lipid storage in muscle, heart, and liver was significantly reduced. Adipose tissue macrophage inflammatory activation was markedly diminished with suppression of adipose tissue apoE expression. Our results establish a novel effect of adipose tissue apoE expression, distinct from circulating apoE, on systemic substrate metabolism and adipose tissue inflammatory state.

The accuracy of vitamin D assays of circulating 25-hydroxyvitamin D values: influence of 25-hydroxylated ergocalciferol concentration.

Serum samples from 74 obese women were assayed for 25-hydroxyvitamin D [25(OH)D] concentrations using an automated immunoassay [Architect (Abbott)] and ELISA (Alpco Diagnostics), and results were compared with the LC/MS/MS reference method (Quest Diagnostics). The Architect values were significantly lower (mean difference: -13 nmol/L; 95% limits: -54; 28 nmol/L) and the ELISA values were significantly higher (mean difference: 24 nmol/L; 95% limits: -36; 84 nmol/L) than the LC/MSIMS values. The slope of the Passing-Bablok regression line relative to LC/MSIMS was 0.5 [95% confidence interval (CI): 0.41; 0.60] and 1.17 (95% CI: 0.87; 1.56) for Architect and ELISA, respectively, with an intercept of approximately 16 for both assays. Using 50 nmol/L as the cut-point for deficiency, Architect and ELISA misclassified 20 and 27% of the subjects, respectively. In subjects with low circulating 25-hydroxylated ergocalciferol [25(OH)D2] (<10 nmol/L), a Bland-Altman plot and Kappa statistics (Kappa = 0.73; 95% CI: 0.49-0.97) showed good agreement between Architect and LC/MS/MS. However, in subjects with high circulating 25(OH)D2 (>or=10 nmol/L), Architect demonstrated poor agreement (Kappa = 0.40; 95% CI: 0.16-0.65). ELISA demonstrated a higher degree of overestimation in women with minimal 25(OH)D2 than those with high 25(OH)D2, suggesting that ELISA overestimates 25-hydroxylated cholecalciferol [25(OH)D3] but underestimates 25(OH)D2.

Adipose tissue changes in obesity and the impact on metabolic function.

Obesity is associated with adverse alterations in adipose tissue that predispose to metabolic dysregulation. These adverse alterations include accumulation of inflammatory macrophages leading to the activation of inflammation pathways, reduction in lipid turnover, and deposition of fat in ectopic locations. These alterations are precursors to the development of insulin resistance and metabolic dysfunction.

Effects of fenofibric acid on carotid intima-media thickness in patients with mixed dyslipidemia on atorvastatin therapy: randomized, placebo-controlled study (FIRST).

OBJECTIVE: To assess whether adding a fibrate to statin therapy reduces residual cardiovascular risk associated with elevated triglycerides and low high-density lipoprotein cholesterol, The Evaluation of Choline Fenofibrate (ABT-335) on Carotid Intima-Media Thickness (cIMT) in Subjects with Type IIb Dyslipidemia with Residual Risk in Addition to Atorvastatin Therapy (FIRST) trial evaluated the effects of fenofibric acid (FA) treatment on cIMT in patients with mixed dyslipidemia on atorvastatin. APPROACH AND RESULTS: This multicenter, double-blind, placebo-controlled study was performed in patients with mixed dyslipidemia (fasting triglycerides, ≥150 mg/dL; high-density lipoprotein cholesterol, ≤45 [men] or 55 mg/dL [women]; low-density lipoprotein cholesterol, ≤100 mg/dL once and averaging ≤105 mg/dL) and a history of coronary heart disease or risk equivalent. Patients on background atorvastatin (continued on starting dose or titrated to 40 mg, if needed) were randomized to FA 135 mg or placebo. The primary end point was rate of change from baseline through week 104 of the mean posterior-wall cIMT, measured by ultrasound. In patients with controlled low-density lipoprotein cholesterol while on atorvastatin background therapy, rate of change in posterior-wall cIMT was similar with FA plus atorvastatin (-0.006 mm/y) versus atorvastatin monotherapy (0.000 mm/y; P=0.22). FA plus atorvastatin was favored (P<0.05) in 5 of 24 prespecified subgroups: age ≥60 years, history of coronary artery disease, cIMT >0.795 mm, triglycerides 170 to 235 mg/dL, and statin use at entry. Adverse events were consistent with the known safety profiles of both drugs; however, FA plus atorvastatin was associated with a greater incidence of renal-related adverse events compared with atorvastatin monotherapy (6.5% versus 0.9%). CONCLUSIONS: Compared with atorvastatin monotherapy, FA plus atorvastatin did not further decrease cIMT progression in high-risk patients with mixed dyslipidemia.

Predictors of stroke in patients with impaired glucose tolerance: results from the Nateglinide and Valsartan in Impaired Glucose Tolerance Outcomes Research trial.

BACKGROUND AND PURPOSE: Risk factors for stroke are well-established in general populations but sparsely studied in individuals with impaired glucose tolerance. METHODS: We identified predictors of stroke among participants with impaired glucose tolerance in the Nateglinide and Valsartan in Impaired Glucose Tolerance Outcomes Research (NAVIGATOR) trial. Cox proportional-hazard regression models were constructed using baseline variables, including the 2 medications studied, valsartan and nateglinide. RESULTS: Among 9306 participants, 237 experienced a stroke over 6.4 years. Predictors of stroke included classical risk factors such as existing cerebrovascular and coronary heart disease, higher pulse pressure, higher low-density lipoprotein cholesterol, older age, and atrial fibrillation. Other factors, including previous venous thromboembolism, higher waist circumference, lower estimated glomerular filtration rate, lower heart rate, and lower body mass index, provided additional important predictive information, yielding a C-index of 0.72. Glycemic measures were not predictive of stroke. Variables associated with stroke were similar in participants with no prior history of cerebrovascular disease at baseline. CONCLUSIONS: The most powerful predictors of stroke in patients with impaired glucose tolerance included a combination of established risk factors and novel variables, such as previous venous thromboembolism and elevated waist circumference, allowing moderately effective identification of high-risk individuals.

Predictors of incident heart failure hospitalizations among patients with impaired glucose tolerance: insight from the Nateglinide And Valsartan in Impaired Glucose Tolerance Outcomes Research study.

BACKGROUND: Impaired glucose tolerance and metabolic syndrome are associated with increased risk of heart failure (HF). However, predictors associated with the increased risk of incident HF have not been well characterized. We aimed to identify independent predictors of incident HF hospitalization among patients with impaired glucose tolerance. METHODS AND RESULTS: In Nateglinide and Valsartan in Impaired Glucose Tolerance Outcomes Research (NAVIGATOR), 9306 research participants with impaired glucose tolerance and ≥1 cardiovascular risk factors were randomized to valsartan versus placebo and nateglinide versus placebo in a 2×2 factorial manner, with a median follow-up of 6.5 years. Using a multivariable Cox proportional hazards model, we analyzed the relationships among baseline clinical factors and the outcome of incident HF hospitalization in patients without history of HF. Significant predictors were identified by forward selection. Increasing age, history of coronary heart disease, and atrial fibrillation or flutter were among several known independent predictors of incident HF hospitalization. Increased waist circumference (hazard ratio per 10 cm, 1.37; 95% confidence interval, 1.21-1.55; P<0.001) and increased urinary albumin-creatinine ratio (P<0.001) were identified as novel predictors. The predictive model for incident HF hospitalization showed good discrimination, with an optimism-corrected C-index of 0.79. CONCLUSIONS: Among research participants with impaired glucose tolerance, there are several easily identifiable predictors of incident HF hospitalization, including traditional risk factors and novel indices of central adiposity and increased urinary albumin-creatinine ratio, which enable further risk stratification and help distinguish patients who could benefit from more aggressive risk factor management.

PCOS is associated with increased CD11c expression and crown-like structures in adipose tissue and increased central abdominal fat depots independent of obesity.

CONTEXT: Adipose tissue macrophage (ATM) infiltration is a major pathway for obesity-induced insulin resistance but has not been studied as a mechanism for insulin resistance in PCOS. OBJECTIVE: We tested whether polycystic ovary syndrome (PCOS) is associated with increased ATM infiltration, especially of inflammatory subtype identified by the CD11c marker. DESIGN AND SETTING: We conducted a case-control study at an academic medical center in the United States. PARTICIPANTS AND INTERVENTIONS: Fourteen PCOS and 14 control women of similar age and body mass index (BMI) underwent a gluteal fat biopsy. Markers of ATM, integrins, TNF-α, and adiponectin, were analyzed by quantitative RT-PCR using a standard curve method. Crown-like structures (CLS) were identified by immunohistochemistry. Abdominal magnetic resonance imaging and frequently sampled i.v. glucose tolerance test were performed to assess abdominal fat and insulin sensitivity (SI). MAIN OUTCOME: Women with PCOS were compared with control women of similar age and BMI for ATM markers, CLS density, adipose tissue expression of inflammatory cytokines and adiponectin, SI, and abdominal fat depots. RESULTS: Women with PCOS had an increase in CD11c expression (P = 0.03), CLS density (P = 0.001), α5 expression (P = 0.009), borderline increase in TNF-α expression (P = 0.08), and a decrease in adiponectin expression (P = 0.02) in gluteal adipose tissue. Visceral (P = 0.009) and sc abdominal fat (P = 0.005) were increased in PCOS. SI was lower in PCOS (P = 0.008). CONCLUSIONS: PCOS is associated with an increase in CD11c expression and CLS density and a decrease in adiponectin expression in sc adipose tissue. Additionally, PCOS is associated with higher central abdominal fat depots independent of BMI. These alterations are present among mostly nonobese women and could represent mechanisms for insulin resistance.

ApoE derived from adipose tissue does not suppress atherosclerosis or correct hyperlipidemia in apoE knockout mice.

The synthesis of apoE by adipocytes has profound effects on adipose tissue lipid flux and gene expression. Using adipose tissue transplantation from wild-type (WT) to apoE knockout (EKO) mice, we show that adipose tissue also contributes to circulating apoE. Different from circulating apoE produced by bone marrow transplantation (BMT), however, adipose tissue-derived apoE does not correct hyperlipidemia or suppress atherosclerosis. ApoE secreted by macrophages has a more acidic isoform distribution, and it increases binding of reconstituted VLDL particles to hepatocytes and fibroblasts more effectively than apoE secreted by adipocytes. The incremental binding can be entirely accounted for by binding to the LDL receptor. After BMT into EKO hosts, plasma cholesterol and macrophage-derived apoE are largely within IDL/LDL- and HDL-sized particles. After adipose tissue transplantation, most cholesterol and adipocyte apoE remain in VLDL. After BMT, circulating apoE no longer demonstrates predominance of acidic isoforms compared with that circulating after fat transplantation. In conclusion, fat transplantation provides circulating apoE levels similar to those provided by bone marrow transplantation, but it does not suppress hyperlipidemia or atherosclerosis. A potential mechanism contributing to this difference is differential binding to cell surface lipoprotein receptors.

Predictors of cardiovascular events in a contemporary population with impaired glucose tolerance: an observational analysis of the Nateglinide and Valsartan in impaired glucose tolerance outcomes research (NAVIGATOR) trial.

OBJECTIVES: Risk factors for cardiovascular events are well established in general populations and those with diabetes but have been sparsely studied in impaired glucose tolerance (IGT). We sought to identify predictors of (1) a composite cardiovascular outcome (cardiovascular death, non-fatal myocardial infarction and non-fatal stroke) and (2) cardiovascular death, among patients with IGT. DESIGN: We studied participants enrolled in the Nateglinide and Valsartan in Impaired Glucose Tolerance Outcomes Research (NAVIGATOR) trial. Predictors of cardiovascular events were identified in observational analyses. SETTING: Clinical trial participants in 40 countries. PARTICIPANTS: 9306 participants with biochemically confirmed IGT at high risk of cardiovascular events participated in NAVIGATOR. PRIMARY AND SECONDARY OUTCOME MEASURES: Cox proportional hazard regression models were constructed using variables (demographic data, medical history, clinical features, biochemical results and ECG findings) recorded at baseline to identify variables associated with and predictive of cardiovascular events. RESULTS: Over 6.4 years, 639 (6.9%) participants experienced a cardiovascular event, and 244 (2.6%) cardiovascular death. While predictors of both outcomes included established risk factors such as existing cardiovascular disease, male gender, older age, current smoking status and higher low-density lipoprotein cholesterol, other variables such as reduced estimated glomerular filtration rate, previous thromboembolic disease, atrial fibrillation, higher urinary albumin/creatinine ratio and chronic obstructive pulmonary disease were also important predictors. Glycaemic measures were not predictive of cardiovascular events. c-Statistics for predicting cardiovascular events and cardiovascular death were 0.74 and 0.82, respectively. This compares with c-statistics for cardiovascular events and cardiovascular death of 0.65 and 0.71, respectively, using the classical Framingham risk factors of age, total cholesterol, high-density lipoprotein cholesterol, systolic blood pressure, treatment for hypertension and smoking status. CONCLUSIONS: The most powerful independent predictors of cardiovascular events in IGT included both established risk factors and other variables excluding measures of glycaemia, allowing effective identification of high-risk individuals.

Apolipoprotein E enhances endothelial-NO production by modulating caveolin 1 interaction with endothelial NO synthase.

Apolipoprotein E (apoE) is widely expressed in mammalian tissues, and one of the important tissue-specific effects is the atheroprotection ascribed to macrophage-derived apoE in the arterial wall. However, underlying mechanisms are not well understood. In this study, using subcellular fractionation, confocal microscopy, and coimmunoprecipitation, we demonstrated that macrophage-derived apoE is internalized by endothelial cells and impacts the subcellular distribution/interaction of caveolin 1 (cav-1) and endothelial NO synthase (eNOS). The addition of apoE disrupts the heteromeric complex formed between cav-1 and eNOS, and increases NO production. Sterol and oxysterol enhance endothelial cav-1/eNOS interaction and suppress NO production, but these effects are reversed by apoE. Silencing endothelial cav-1 attenuates apoE-induced NO production, establishing the importance of the cav-1-eNOS interaction for the increment in endothelial NO produced by apoE. Consistent with these observations, macrophage-derived apoE significantly improves vasodilation to acetylcholine in resistance arteries isolated from adipose tissue of obese humans. We conclude that macrophage-derived apoE enhances endothelial NO production by disrupting the inhibitory interaction of eNOS with cav-1. These results establish a novel mechanism by which apoE modulates endothelial cell function.

The role of oxysterols in control of endothelial stiffness.

Endothelial dysfunction is a key step in atherosclerosis development. Our recent studies suggested that oxLDL-induced increase in endothelial stiffness plays a major role in dyslipidemia-induced endothelial dysfunction. In this study, we identify oxysterols, as the major component of oxLDL, responsible for the increase in endothelial stiffness. Using Atomic Force Microscopy to measure endothelial elastic modulus, we show that endothelial stiffness increases with progressive oxidation of LDL and that the two lipid fractions that contribute to endothelial stiffening are oxysterols and oxidized phosphatidylcholines, with oxysterols having the dominant effect. Furthermore, endothelial elastic modulus increases as a linear function of oxysterol content of oxLDL. Specific oxysterols, however, have differential effects on endothelial stiffness with 7-ketocholesterol and 7α-hydroxycholesterol, the two major oxysterols in oxLDL, having the strongest effects. 27-hydroxycholesterol, found in atherosclerotic lesions, also induces endothelial stiffening. For all oxysterols, endothelial stiffening is reversible by enriching the cells with cholesterol. oxLDL-induced stiffening is accompanied by incorporation of oxysterols into endothelial cells. We find significant accumulation of three oxysterols, 7α-hydroxycholesterol, 7ß-hydroxycholesterol, and 7-ketocholesterol, in mouse aortas of dyslipidemic ApoE⁻/⁻ mice at the early stage of atherosclerosis. Remarkably, these are the same oxysterols we have identified to induce endothelial stiffening.

Reversal of type 1 diabetes via islet ß cell regeneration following immune modulation by cord blood-derived multipotent stem cells.

BACKGROUND: Inability to control autoimmunity is the primary barrier to developing a cure for type 1 diabetes (T1D). Evidence that human cord blood-derived multipotent stem cells (CB-SCs) can control autoimmune responses by altering regulatory T cells (Tregs) and human islet ß cell-specific T cell clones offers promise for a new approach to overcome the autoimmunity underlying T1D. METHODS: We developed a procedure for Stem Cell Educator therapy in which a patient's blood is circulated through a closed-loop system that separates lymphocytes from the whole blood and briefly co-cultures them with adherent CB-SCs before returning them to the patient's circulation. In an open-label, phase1/phase 2 study, patients (n=15) with T1D received one treatment with the Stem Cell Educator. Median age was 29 years (range: 15 to 41), and median diabetic history was 8 years (range: 1 to 21). RESULTS: Stem Cell Educator therapy was well tolerated in all participants with minimal pain from two venipunctures and no adverse events. Stem Cell Educator therapy can markedly improve C-peptide levels, reduce the median glycated hemoglobin A1C (HbA1C) values, and decrease the median daily dose of insulin in patients with some residual ß cell function (n=6) and patients with no residual pancreatic islet ß cell function (n=6). Treatment also produced an increase in basal and glucose-stimulated C-peptide levels through 40 weeks. However, participants in the Control Group (n=3) did not exhibit significant change at any follow-up. Individuals who received Stem Cell Educator therapy exhibited increased expression of co-stimulating molecules (specifically, CD28 and ICOS), increases in the number of CD4+CD25+Foxp3+ Tregs, and restoration of Th1/Th2/Th3 cytokine balance. CONCLUSIONS: Stem Cell Educator therapy is safe, and in individuals with moderate or severe T1D, a single treatment produces lasting improvement in metabolic control. Initial results indicate Stem Cell Educator therapy reverses autoimmunity and promotes regeneration of islet ß cells. Successful immune modulation by CB-SCs and the resulting clinical improvement in patient status may have important implications for other autoimmune and inflammation-related diseases without the safety and ethical concerns associated with conventional stem cell-based approaches. TRIAL REGISTRATION: ClinicalTrials.gov number, NCT01350219.

Risk of obstructive sleep apnea in obese and nonobese women with polycystic ovary syndrome and healthy reproductively normal women.

OBJECTIVE: To study the risk for obstructive sleep apnea (OSA) in a group of nonobese and obese polycystic ovary syndrome (PCOS) and control women. DESIGN: Prospective study. SETTING: Academic tertiary care medical center. PATIENT(S): Forty-four women with PCOS and 34 control women. INTERVENTION(S): All of the women completed the Berlin questionnaire for assessment of OSA risk. MAIN OUTCOME MEASURE(S): All of the women underwent fasting determination of androgens, glucose, and insulin. RESULT(S): Women with PCOS were more obese compared with control women. However, there were no differences in BMI once subjects were divided into nonobese (PCOS: n = 17; control: n = 26) and obese (PCOS: n = 27; control: n = 8) groups. Women with PCOS had higher prevalence of high-risk OSA compared with control women (47% vs. 15%). However, none of the nonobese PCOS and control women screened positively for high-risk OSA. Among the obese group, the risk did not differ between groups (77% vs. 63%). CONCLUSION(S): Our findings indicate that even though the risk for OSA in PCOS is high, it is related to the high prevalence of severe obesity. The risk for OSA among nonobese women with PCOS is very low. However, our findings are limited by lack of polysomnographic confirmation of OSA.

Pioglitazone-mediated changes in lipoprotein particle composition are predicted by changes in adiponectin level in type 2 diabetes.

CONTEXT: In animal and observational studies, adiponectin is associated with lipoprotein risk factors for cardiovascular disease. OBJECTIVE: We analyzed data from a randomized clinical trial to evaluate the relationship between changes in adiponectin to changes in lipoprotein risk factors after an intervention that alters adiponectin levels. DESIGN AND SETTING: Adiponectin levels were measured at baseline and follow-up, as were lipoprotein risk factors for cardiovascular disease, at academic medical centers and ambulatory care centers. PATIENTS AND OTHER PARTICIPANTS: Participants included 361 men and women with type 2 diabetes. INTERVENTION: Intervention included randomization to treatment with glimepiride or pioglitazone for 72 wk. MAIN OUTCOME MEASURE: The relationship of treatment-related differences in adiponectin level to treatment-related differences in lipoprotein cardiovascular risk factors at 72 wk was evaluated. RESULTS: Pioglitazone led to an increase in adiponectin compared with glimepiride. Compared with baseline, pioglitazone treatment at 72 wk led to an increase in low-density lipoprotein (LDL) and high-density lipoprotein (HDL) particle size and a decrease in very-low-density lipoprotein (VLDL) particle size and LDL particle number. Glimepiride treatment more modestly decreased LDL particle number and increased LDL particle size. At 72 wk, there were significant treatment group differences for HDL, LDL, and VLDL particle size, and triglyceride and HDL cholesterol level. The increase in adiponectin predicted treatment-related improvement for triglyceride and HDL cholesterol level and LDL and HDL particle size. CONCLUSION: Increased adiponectin contributed to treatment-related benefit in lipoprotein cardiovascular disease risk factors in obese diabetic subjects treated with pioglitazone. These results provide support for a model that mechanistically links changes in adiponectin level to changes in lipoprotein composition in humans.

Expression of the human apoE2 isoform in adipocytes: altered cellular processing and impaired adipocyte lipogenesis.

Expression of apoE in adipocytes has been shown to have an important role in modulating adipocyte triglyceride (TG) metabolism and gene expression that is independent of circulating and extracellular apoE. The impact of adipocyte expression of common human apoE isoforms was evaluated using adipocytes harvested from human apoE2, -3, and -4 knock-in mice. Expression of the apoE2 isoform was associated with an increase in adipocyte apoE gene expression and apoE synthesis. Newly synthesized apoE2 was unstable in adipocytes and demonstrated increased degradation and decreased secretion. ApoE2-expressing mice were hyperlipidemic, and had increased size of gonadal fat pads and of adipocytes, compared with apoE3 mice. In isolated cells, however, expression of the apoE2 isoform produced defective lipogenesis and increased TG hydrolysis. Incubation of adipose tissue with apoE3-containing TG-rich lipoproteins resulted in a significant increase in TG in adipose tissue from apoE3 and -E4 mice, but not apoE2 mice. Reduced capacity to internalize FFA as lipogenic substrate contributed to defective lipogenesis. Newly synthesized apoE2 is unstable in adipocytes and results in decreased adipocyte TG synthesis and defective FA uptake. These changes recapitulate those observed in apoE knockout adipocytes and have implications for understanding metabolic disturbances in humans expressing the E2 isoform.

Adipose tissue depot-specific differences in adipocyte apolipoprotein E expression.

Important differences in gene expression have been documented in adipocytes derived from specific adipose tissue depots. We have previously documented an important role for adipocyte apolipoprotein E (apoE) in modulating adipocyte and adipose tissue triglyceride and lipoprotein metabolism. We now evaluate the endogenous expression of apoE in adipocytes isolated from unique adipose tissue depots in 4 different species. Adipocyte apoE expression is higher in subcutaneous fat compared with visceral fat in humans, mice, rats, and baboons. In baboons, evaluation of apoE expression in 5 adipose tissue depots (subcutaneous abdominal, subcutaneous gluteal, visceral, pericardial, epicardial) showed that, compared with subcutaneous abdominal adipocytes, the level of apoE expression is similar in subcutaneous gluteal, lower in visceral and pericardial, and higher in epicardial adipocytes. Consistent with previously demonstrated suppression of adipocyte apoE by adipose tissue inflammation, adipose tissue depots with lower apoE expression demonstrated greater infiltration of macrophages and an increased expression of tumor necrosis factor-α messenger RNA. Depot-specific differences in apoE expression were maintained after in vitro differentiation. Adipocytes isolated from depots with lower apoE expression manifested lower rates of triglyceride synthesis in the absence and presence of triglyceride-rich lipoproteins. Adenoviral-mediated increase of apoE expression in omental adipocytes increased triglyceride synthesis in these cells. Our results demonstrate significant heterogeneity in adipocyte apoE expression across adipose tissue depots in several species. Because of its role in modulating adipocyte triglyceride and lipoprotein metabolism, depot-specific differences in endogenous adipocyte apoE could have important implications for modulating the accumulation of lipid in these depots.

Polycystic ovary syndrome is associated with atherogenic changes in lipoprotein particle number and size independent of body weight.

OBJECTIVE: Adverse changes in lipoprotein particle number and size are common with insulin resistance and are associated with increased cardiovascular risk. Comprehensive information regarding lipoprotein particle number and size, and how these parameters relate to body weight, insulin resistance and hyperandrogenemia is lacking in polycystic ovary syndrome (PCOS). We tested the hypothesis that PCOS is associated with atherogenic changes in lipoprotein profile independent of body weight and examined the role of insulin resistance and androgens in these atherogenic changes. DESIGN: Case-control study performed at Clinical Research Center at an Academic Medical Center in the United States. PATIENTS AND MEASUREMENTS: Fasting blood was obtained from 25 PCOS and 25 control women of similar age and body mass index (BMI). Lipoprotein particle number and size was determined by nuclear magnetic resonance and compared between the groups. RESULTS: The mean BMI for both groups was <30 kg/m(2) (P = 0·33). Women with PCOS had an increase in very low-density lipoprotein (VLDL) particle number (P = 0·005), low-density lipoprotein (LDL) particle number (P = 0·02) and a decrease in high-density lipoprotein (HDL) size (P = 0·04). LDL size was borderline decreased (P = 0·09). These differences persisted after adjustment for ethnicity, alcohol and tobacco intake and exercise. In stepwise regression models, bioavailable testosterone was the only predictor of LDL cholesterol, triglyceride, VLDL and LDL particle number. Sex hormone binding globulin (SHBG) was the only predictor of LDL and HDL size. CONCLUSIONS: Independent of body weight, PCOS was associated with changes in lipoprotein profile that increases risk for cardiovascular disease. These changes were present in a mostly nonobese group of women and were more closely related to androgens than fasting insulin.