Detection of Angiotensin II type I-receptor antibodies in transplant glomerulopathy.

BACKGROUND: Transplant glomerulopathy (TG) is an important cause of late graft loss. The role of angiotensin type 1-receptor antibodies (AT1 R-Ab) in TG is not known. METHODS: All the TG cases (N = 137) between January 2007 and December 2014 (N = 1410) were analyzed. Donor-specific anti-HLA antibodies (DSA) at the time of biopsy and AT1 R-Ab IgG (positive, >17 UI/mL; "at risk," 10-17 UI/mL; negative, <10 UI/mL) in pre-transplant sera (PT-Ab) and at biopsy time (BT-Ab) were studied. RESULTS: AT1 R-PT-Ab+ and AT1 R-BT-Ab+ patients were 16.5% (51.5% "at risk") and 11.5% (27.4% "at risk"), respectively. Clinical correlations were found between AT1 R-Ab and HCV infection, number of transplants, and age. Considering Banff scores, ptc was higher in DSA+ patients vs AT1 R-PT-Ab+ (P = 0.002) or AT1 R-BT-Ab+ (P = 0.001) without differences in g and chronicity score (ci + ct); cg showed lower scores in DSA+ patients vs AT1 R-BT-Ab+ (P = 0.001). Graft survival was not influenced by the presence of AT1 R-Ab, AT1-R-Ab titer or MFI, but we observed a longer graft survival in patients with both AT1 R-BT-Ab+ or "at risk" and DSA+ vs patients positive only for DSA (P = 0.02), for AT1 R-BT-Ab (P = 0.019) or AT1 R-BT-Ab "at risk" (P = 0.039). CONCLUSION: AT1 R-Ab showed no independent prognostic role in TG in this pilot analysis.

The pleiotropic actions of rosuvastatin confer renal benefits in the diabetic Apo-E knockout mouse.

Diabetic nephropathy is a leading cause of end-stage renal disease. Statins may exert renoprotective effects independently of lipid-lowering properties. We investigated the pleiotropic effects of rosuvastatin on renal structure and function in streptozotocin diabetic apolipoprotein-E knockout (Apo-E(-/-)) mice, a model of progressive nephropathy in which dyslipidemia is resistant to statin treatment. These effects were compared with those observed with conventional renin-angiotensin system blockade (candesartan) or combined treatment. Nondiabetic and diabetic Apo-E(-/-) mice were randomized to no treatment or treatment with candesartan (2.5 mg/kg), rosuvastatin (5 mg/kg), or their combination per gavage for 20 wk. Urine and blood samples were collected for assessment of albuminuria, creatinine clearance, plasma lipids, glucose, and glycated hemoglobin. Renal sclerosis was analyzed on paraffin-embedded kidney sections stained with periodic acid-Schiff. Renal expression of collagen IV, fibronectin and advanced glycation end products (AGEs), receptor for advanced glycation and products (RAGE), NADPH oxidase 4 (NOX4), and nitrotyrosine was assessed by real-time PCR and/or immunohistochemistry. Diabetes-induced albuminuria was not affected by rosuvastatin and combination treatment but was prevented by candesartan. Diabetes resulted in increased creatinine clearance, which was not modified by the treatments. Rosuvastatin and/or candesartan prevented diabetes-associated renal extracellular matrix accumulation. Rosuvastatin reduced accumulation of AGEs and expression of RAGE, NOX4, and nitrotyrosine. In conclusion, in the diabetic Apo-E(-/-) mouse, rosuvastatin confers renal benefits that are independent of lipid lowering and equivalent or greater to those observed with candesartan. The combination treatment is not superior to monotherapies.

Islet-Like Structures Generated In Vitro from Adult Human Liver Stem Cells Revert Hyperglycemia in Diabetic SCID Mice.

A potential therapeutic strategy for diabetes is the transplantation of induced-insulin secreting cells. Based on the common embryonic origin of liver and pancreas, we studied the potential of adult human liver stem-like cells (HLSC) to generate in vitro insulin-producing 3D spheroid structures (HLSC-ILS). HLSC-ILS were generated by a one-step protocol based on charge dependent aggregation of HLSC induced by protamine. 3D aggregation promoted the spontaneous differentiation into cells expressing insulin and several key markers of pancreatic ß cells. HLSC-ILS showed endocrine granules similar to those seen in human ß cells. In static and dynamic in vitro conditions, such structures produced C-peptide after stimulation with high glucose. HLSC-ILS significantly reduced hyperglycemia and restored a normo-glycemic profile when implanted in streptozotocin-diabetic SCID mice. Diabetic mice expressed human C-peptide and very low or undetectable levels of murine C-peptide. Hyperglycemia and a diabetic profile were restored after HLSC-ISL explant. The gene expression profile of in vitro generated HLSC-ILS showed a differentiation from HLSC profile and an endocrine commitment with the enhanced expression of several markers of ß cell differentiation. The comparative analysis of gene expression profiles after 2 and 4 weeks of in vivo implantation showed a further ß-cell differentiation, with a genetic profile still immature but closer to that of human islets. In conclusion, protamine-induced spheroid aggregation of HLSC triggers a spontaneous differentiation to an endocrine phenotype. Although the in vitro differentiated HLSC-ILS were immature, they responded to high glucose with insulin secretion and in vivo reversed hyperglycemia in diabetic SCID mice.

Lack of the antioxidant enzyme glutathione peroxidase-1 accelerates atherosclerosis in diabetic apolipoprotein E-deficient mice.

BACKGROUND: Recent clinical studies have suggested a major protective role for the antioxidant enzyme glutathione peroxidase-1 (GPx1) in diabetes-associated atherosclerosis. We induced diabetes in mice deficient for both GPx1 and apolipoprotein E (ApoE) to determine whether this is merely an association or whether GPx1 has a direct effect on diabetes-associated atherosclerosis. METHODS AND RESULTS: ApoE-deficient (ApoE-/-) and ApoE/GPx1 double-knockout (ApoE-/- GPx1-/-) mice were made diabetic with streptozotocin and aortic lesion formation, and atherogenic pathways were assessed after 10 and 20 weeks of diabetes. Aortic proinflammatory and profibrotic markers were determined by both quantitative reverse-transcription polymerase chain reaction analysis after 10 weeks of diabetes and immunohistochemical analysis after 10 and 20 weeks of diabetes. Sham-injected nondiabetic counterparts served as controls. Atherosclerotic lesions within the aortic sinus region, as well as arch, thoracic, and abdominal lesions, were significantly increased in diabetic ApoE-/- GPx1-/- aortas compared with diabetic ApoE-/- aortas. This increase was accompanied by increased macrophages, alpha-smooth muscle actin, receptors for advanced glycation end products, and various proinflammatory (vascular cell adhesion molecule-1) and profibrotic (vascular endothelial growth factor and connective tissue growth factor) markers. Quantitative reverse-transcription polymerase chain reaction analysis showed increased expression of receptors for advanced glycation end products (RAGE), vascular cell adhesion molecule-1, vascular endothelial growth factor, and connective tissue growth factor. Nitrotyrosine levels were significantly increased in diabetic ApoE-/- GPx1-/- mouse aortas. These findings were observed despite upregulation of other antioxidants. CONCLUSIONS: Lack of functional GPx1 accelerates diabetes-associated atherosclerosis via upregulation of proinflammatory and profibrotic pathways in ApoE-/- mice. Our study provides evidence of a protective role for GPx1 and establishes GPx1 as an important antiatherogenic therapeutic target in patients with or at risk of diabetic macrovascular disease.

Urinalysis: do not forget this type of cell in renal transplantation.

Microscopic sediment analysis of urine from a 56-year-old woman who underwent renal transplantation showed many uncommon clusters of rounded and translucent cells containing globular mucous cytoplasmic inclusions (HPF, x400). These cells were bigger than leukocytes and, compared with uroepithelial cells, showed a smaller nucleus to cytoplasm ratio and appeared eosinophilic, being pink rather than azurophilic with Sternheimer-Malbin stain. They were also unlikely to be tubular cells, which are usually smaller, singly distributed and associated with dysmorphic erythrocytes and/or casts and/or a worsening in renal function. A review of the patient's history showed that a pretransplantation urologic surgical treatment, including ileal bladder reconstruction, had been performed. Intestinal epithelial cells should be remembered when examining urinary sediment.

Renal Regenerative Potential of Different Extracellular Vesicle Populations Derived from Bone Marrow Mesenchymal Stromal Cells.

Extracellular vesicles (EVs) derived from human bone marrow mesenchymal stromal cells (MSCs) promote the regeneration of kidneys in different animal models of acute kidney injury (AKI) in a manner comparable with the cells of origin. However, due to the heterogeneity observed in the EVs isolated from MSCs, it is unclear which population is responsible for the proregenerative effects. We therefore evaluated the effect of various EV populations separated by differential ultracentrifugation (10K population enriched with microvesicles and 100K population enriched with exosomes) on AKI recovery. Only the exosomal-enriched population induced an improvement of renal function and morphology comparable with that of the total EV population. Interestingly, the 100K EVs exerted a proproliferative effect on murine tubular epithelial cells, both in vitro and in vivo. Analysis of the molecular content from the different EV populations revealed a distinct profile. The 100K population, for instance, was enriched in specific mRNAs (CCNB1, CDK8, CDC6) reported to influence cell cycle entry and progression; miRNAs involved in regulating proliferative/antiapoptotic pathways and growth factors (hepatocyte growth factor and insulin-like growth factor-1) that could explain the effect of renal tubular cell proliferation. On the other hand, the EV population enriched in microvesicles (10K) was unable to induce renal regeneration and had a molecular profile with lower expression of proproliferative molecules. In conclusion, the different molecular composition of exosome- and microvesicle-enriched populations may explain the regenerative effect of EVs observed in AKI.

Incidence of prolonged QTc and severe hypoglycemia in type 1 diabetes: the EURODIAB Prospective Complications Study.

AIMS: To assess the independent role of severe hypoglycemia on 7-year cumulative incidence of prolonged QTc in a large cohort of patients with type 1 diabetes. METHODS: People with type 1 diabetes recruited by the EURODIAB Prospective Complications Study who had normal QTc were examined at baseline and after 7 years with standardized methods (n = 1415; mean age ± SD 32.1 ± 9.6 years; diabetes duration 14.2 ± 8.8 years). Hypoglycemic episodes were assessed by a questionnaire. QTc was calculated according to Bazett's formula. In logistic regression analysis, we examined the role of severe hypoglycemia (none, 1-2, or 3 and more episodes/year) on the cumulative incidence of prolonged QTc, independently of age, sex, HbA1c, blood pressure, BMI, physical activity, distal symmetrical and autonomic neuropathy. RESULTS: In total, 264/1415 (17%) patients had incident prolonged QTc. Compared to those with persistently normal QTc, a greater proportion of incident cases had 3 and more hypoglycemic episodes at baseline (16.3 vs 11.2%, p = 0.03) and after 7 years (15.2 vs 9.6%, p = 0.01). In logistic regression analysis, 3 or more episodes of severe hypoglycemia at baseline did not increase cumulative incidence of prolonged QTc (OR 1.34, 95% CI 0.88-2.03). By contrast, severe hypoglycemia at the follow-up examination was associated with higher incidence of QTc prolongation (OR 1.68, 1.09-2.58), which reverted to not significant after adjustment for diabetic neuropathy. CONCLUSIONS: Severe hypoglycemia was not associated with incidence QTc prolongation in type 1 diabetic patients from the EURODIAB PCS.

Management strategies for patients with hypertension and diabetes: why combination therapy is critical.

Hypertension is commonly associated and acts synergistically with diabetes in increasing the risk of macrovascular and microvascular diabetic complications. Large-scale clinical trials have demonstrated that this risk is significantly reduced by intensive antihypertensive treatment, and accordingly, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure guideline has further lowered the blood pressure goals for diabetic subjects to <130/80 mm Hg. This implies that most diabetic patients will require the combination of two or more antihypertensive agents to achieve this blood pressure target. Although the most effective combination strategy in diabetes has not yet been determined in large-scale randomized clinical trials, a combination that includes at least one agent that interrupts the renin-angiotensin system appears to not only have a good safety profile, but may also provide additional renal and cardiovascular protection. Other antihypertensive agents should be added based on the patients risk profile and overall treatment regimen to achieve blood pressure goal.

Angiopoietin 2 induces cell cycle arrest in endothelial cells: a possible mechanism involved in advanced plaque neovascularization.

OBJECTIVE: To characterize the molecules and the mechanisms regulating the neoangiogenetic process in advanced atherosclerotic plaques. METHODS AND RESULTS: Western blot and immunofluorescence analysis of atherosclerotic specimens demonstrated that unlike neovessels from early lesions that expressed vascular endothelial growth factor (VEGF) and angiopoietin1 (Angio1), vessels from advanced lesions expressed VEGF and angiopoietin 2 (Angio2). Moreover, only few neovessels from advanced lesions showed a positive immunostaining for proliferating cell nuclear antigen. Angio1-elicited and Angio2-elicited intracellular events in endothelial cells (EC) demonstrated that while Angio1 triggered Erk1/Erk2 mitogen activated protein kinases (MAPK) and Akt activation, Angio2 (50 ng/mL) induced STAT5 activation and p21waf expression and increased the fraction of cells in G1. Both Angio2-mediated events were abrogated by expressing a dominant negative STAT5 construct (DeltaSTAT5). Consistent with the expression of Angio2 in neovessels of advanced lesions a transcriptionally active STAT5 was detected. Moreover, co-immunoprecipitation experiments revealed the presence of a STAT5/Tie2 molecular complex in neointima vessels from advanced, but not from early, lesions. CONCLUSIONS: In advanced lesions, the activation of the Tie2-mediated STAT5 signaling pathway may negatively regulate vessel growth.

Prevalence of Q-T interval dispersion in type 1 diabetes and its relation with cardiac ischemia : the EURODIAB IDDM Complications Study Group.

OBJECTIVE: The interlead variation in duration of the Q-T interval on the surface electrocardiogram (Q-T interval dispersion [QTd]) has been shown to predict mortality in type 2 diabetic patients. We evaluated the prevalence of QTd prolongation in the EURODIAB population and its relation to corrected Q-T interval (QTc), sex, age, duration of diabetes, blood glucose control, and complications. RESEARCH DESIGN AND METHODS; A total of 3,042 type 1 diabetic patients were studied. QTc was calculated according to the Bazett's formula; QTc > 0.44 s was considered abnormally prolonged. QTd was calculated using the difference between the maximum and the minimum QTc in any thoracic lead. QTd >0.080 s was considered abnormally prolonged. RESULTS: The prevalence of an increased QTd was 7%. A significant relation was observed between QTd prolongation and diastolic blood pressure (P < 0.05). A higher prevalence of QTd prolongation was observed in patients with ischemic heart disease (P = 0.004), whereas no relationship was observed with retinopathy, albumin excretion rate, or measures of somatic and autonomic neuropathy. QTc and QTd were significantly related (P = 0.001); however, a proportion of patients with normal QTd showed a prolonged QTc (>0.44 s). CONCLUSIONS: In patients with type 1 diabetes, QTd is associated with ischemic heart disease and diastolic blood pressure but not neuropathy. Although QTd is statistically related to duration of QTc, increased QTd and increased QTc identify different patients, and their predictive value deserves prospective evaluation.

Circulating anti-Hsp70 levels in nascent metabolic syndrome: the Casale Monferrato Study.

The metabolic syndrome (MetS) confers an increased risk of both type 2 diabetes and cardiovascular diseases (CVD). Heat shock protein 70 (Hsp70), an intracellular polypeptide, can be exposed on the plasma membrane and/or released into the circulation, eliciting both native and immune responses that may contribute to vascular damage. Our aim was to assess if serum anti-Hsp70 antibody levels were cross-sectionally associated with uncomplicated MetS. A cross-sectional case-control study from the nondiabetic cohort of the Casale Monferrato Study was performed. Subjects with established CVD and/or abnormal renal function were excluded. Case subjects (n = 180) were defined as those fulfilling the criteria for the diagnosis of MetS. Control subjects (n = 136) were completely free of any component of the MetS. Serum anti-Hsp70 levels were measured by immunoenzymatic assay. We found that anti-Hsp70 antibody levels were significantly higher in cases than in control subjects [122.6 (89.5-155.6) vs 107.1 (77.3-152.4) µg/ml, p = 0.04], even after age and sex adjustment. In logistic regression analysis, higher levels of log-anti-Hsp70 conferred greater odds ratio (OR) for MetS, independently of age and sex. There was a statistically significant trend of ORs across quartiles of anti-Hsp70 and values greater than 108.0 µg/ml conferred a 77% increased OR of MetS as compared with values in the lower quartiles. The strength of the association slightly decreased after further adjustment for apolipoprotein B, smoking, and albumin excretion rate. In conclusion, our results show that serum anti-Hsp70 antibody levels are independently associated with nascent MetS.

Increased QT interval dispersion predicts 15-year cardiovascular mortality in type 2 diabetic subjects: the population-based Casale Monferrato Study.

OBJECTIVE: To evaluate the predictive role of increased corrected QT (QTc) and QT interval dispersion (QTd) on all-cause and cardiovascular mortality in a large, unselected type 2 diabetic population. RESEARCH DESIGN AND METHODS: The prospective study included 1,357 type 2 diabetic patients from the Casale Monferrato Study. At baseline, QTc intervals >0.44 s and QTd intervals >0.08 s were considered abnormally prolonged. Both all-cause and cardiovascular mortality were assessed 15 years after the baseline examination. RESULTS: During the follow-up period, 862 subjects per 12,450 person-years died. Multivariate analysis showed that the hazard ratio (HR) of cardiovascular mortality was significantly increased in subjects with prolonged QTd (1.26 [95% CI 1.02-1.55]) and was only slightly reduced after multiple adjustments. Conversely, prolonged QTc did not increase the HRs for all-cause or cardiovascular mortality. CONCLUSIONS: Increased QTd predicts cardiovascular mortality after a long-term follow-up period in a large, unselected population of type 2 diabetic subjects.

QTc interval prolongation is independently associated with severe hypoglycemic attacks in type 1 diabetes from the EURODIAB IDDM complications study.

OBJECTIVE: Our aim was to assess whether severe hypoglycemic attacks were cross-sectionally associated with abnormalities of the QTc interval in type 1 diabetic patients. RESEARCH DESIGN AND METHODS: The study included 3,248 type 1 diabetic patients from the EURODIAB IDDM Complications Study. Severe hypoglycemia was defined as an attack serious enough to require the help of another person. A corrected QTc interval (QTc) >0.44 s was considered abnormally prolonged. RESULTS: Nineteen percent of patients declared one to two attacks, and 13.2% of patients had three or more attacks. Prevalence of QTc prolongation was greater in patients who experienced three or more hypoglycemic attacks. Logistic regression analysis showed that the frequency of severe hypoglycemia was independently associated with QTc prolongation, even after adjustment for diabetes complications, including autonomic neuropathy (odds ratio 1.27, 95% CI 1.02-1.58). CONCLUSIONS: We have provided evidence that severe hypoglycemic attacks are independently associated with a prolonged QTc interval in type 1 diabetic patients from the EURODIAB IDDM Complications Study.

Targeting the MCP-1/CCR2 System in diabetic kidney disease.

Diabetic nephropathy is the leading cause of end-stage renal failure in the Western World and accounts for significant morbidity and mortality in patients with diabetes. Although hyperglycaemia and hypertension are established key determinants in the development of the complication, recent studies suggest that a low-grade inflammatory response may also play a role. Monocyte Chemoattractant Protein 1 (MCP-1), a potent chemokine produced by renal cells, has emerged as a very important player in this process. Specifically, it has been shown that MCP-1 is overexpressed in the kidneys from diabetic animals. Furthermore, there is amelioration of both functional and structural abnormalities in MCP-1- knockout mice in the setting of concomitant diabetes. Over recent years the cellular mechanisms linking MCP-1 to kidney injury have been increasingly delineated and, in particular, it has become evident that MCP-1 contributes to the kidney damage not only by inducing mononuclear cell recruitment, but also by direct activation of resident renal cells. The present review focuses on the most significant advances in understanding the role of MCP-1 in diabetic kidney disease and future potential therapeutic implications.

Effect of the monocyte chemoattractant protein-1/CC chemokine receptor 2 system on nephrin expression in streptozotocin-treated mice and human cultured podocytes.

OBJECTIVE: Monocyte chemoattractant protein-1 (MCP-1), a chemokine binding to the CC chemokine receptor 2 (CCR2) and promoting monocyte infiltration, has been implicated in the pathogenesis of diabetic nephropathy. To assess the potential relevance of the MCP-1/CCR2 system in the pathogenesis of diabetic proteinuria, we studied in vitro if MCP-1 binding to the CCR2 receptor modulates nephrin expression in cultured podocytes. Moreover, we investigated in vivo if glomerular CCR2 expression is altered in kidney biopsies from patients with diabetic nephropathy and whether lack of MCP-1 affects proteinuria and expression of nephrin in experimental diabetes. RESEARCH DESIGN AND METHODS: Expression of nephrin was assessed in human podocytes exposed to rh-MCP-1 by immunofluorescence and real-time PCR. Glomerular CCR2 expression was studied in 10 kidney sections from patients with overt nephropathy and eight control subjects by immunohistochemistry. Both wild-type and MCP-1 knockout mice were made diabetic with streptozotocin. Ten weeks after the onset of diabetes, albuminuria and expression of nephrin, synaptopodin, and zonula occludens-1 were examined by immunofluorescence and immunoblotting. RESULTS: In human podocytes, MCP-1 binding to the CCR2 receptor induced a significant reduction in nephrin both mRNA and protein expression via a Rho-dependent mechanism. The MCP-1 receptor, CCR2, was overexpressed in the glomerular podocytes of patients with overt nephropathy. In experimental diabetes, MCP-1 was overexpressed within the glomeruli and the absence of MCP-1 reduced both albuminuria and downregulation of nephrin and synaptopodin. CONCLUSIONS: These findings suggest that the MCP-1/CCR2 system may be relevant in the pathogenesis of proteinuria in diabetes.

Heat shock protein expression in diabetic nephropathy.

Heat shock protein (HSP) HSP27, HSP60, HSP70, and HSP90 are induced by cellular stresses and play a key role in cytoprotection. Both hyperglycemia and glomerular hypertension are crucial determinants in the pathogenesis of diabetic nephropathy and impose cellular stresses on renal target cells. We studied both the expression and the phosphorylation state of HSP27, HSP60, HSP70, and HSP90 in vivo in rats made diabetic with streptozotocin and in vitro in mesangial cells and podocytes exposed to either high glucose or mechanical stretch. Diabetic and control animals were studied 4, 12, and 24 wk after the onset of diabetes. Immunohistochemical analysis revealed an overexpression of HSP25, HSP60, and HSP72 in the diabetic outer medulla, whereas no differences were seen in the glomeruli. Similarly, exposure neither to high glucose nor to stretch altered HSP expression in mesangial cells and podocytes. By contrast, the phosphorylated form of HSP27 was enhanced in the glomerular podocytes of diabetic animals, and in vitro exposure of podocytes to stretch induced HSP27 phosphorylation via a P38-dependent mechanism. In conclusion, diabetes and diabetes-related insults differentially modulate HSP27, HSP60, and HSP70 expression/phosphorylation in the glomeruli and in the medulla, and this may affect the ability of renal cells to mount an effective cytoprotective response.

Incidence and risk factors of prolonged QTc interval in type 1 diabetes: the EURODIAB Prospective Complications Study.

OBJECTIVE: Corrected QT (QTc) prolongation is predictive of cardiovascular mortality in both the general and diabetic populations. As part of the EURODIAB Prospective Complication Study, we have assessed the 7-year incidence and risk factors of prolonged QTc in people with type 1 diabetes. RESEARCH DESIGN AND METHODS: A total of 1,415 type 1 diabetic subjects, who had normal QTc at baseline, were reanalyzed after the 7-year follow-up period. QTc >0.44 s was considered abnormally prolonged. RESULTS: Cumulative incidence of prolonged QTc was 18.7%, which is twofold higher in women than in men (24.5 vs. 13.9%, P < 0.0001). At the baseline examination, incident cases were older and less physically active than nonincident cases, had higher mean values of systolic blood pressure and HDL cholesterol, and had higher frequencies of hypertension, coronary heart disease, and distal symmetrical polyneuropathy. In multivariate logistic regression analyses, female sex and higher values of A1C and systolic blood pressure were associated with the risk of prolonged QTc, whereas physical activity and BMI within the range of 21.5-23.2 kg/m2 were protective factors. In women, association with modifiable factors, particularly BMI, was stronger than in men. CONCLUSIONS: In type 1 diabetic subjects from the EURODIAB cohort, female sex, A1C, and systolic blood pressure are predictive of prolonged QTc, whereas physical activity and BMI within the range of 21.5-23.2 kg/m2 play a protective role. These findings are clinically relevant, as they may help to identify subjects at higher risk for prolonged QTc, as well as provide potential targets for risk-lowering strategies.