Longitudinal Changes in Circulating Ketone Body Levels in Patients With Acute Heart Failure: A Post Hoc Analysis of the EMPA-Response-AHF Trial.

BACKGROUND: Ketone bodies are endogenous fuels produced by the liver under conditions of metabolic or neurohormonal stress. Circulating ketone bodies are increased in patients with chronic heart failure (HF), yet little is known about the effect of acute HF on ketosis. We tested the hypothesis that ketogenesis is increased in patients with acute decompensated HF. METHODS AND RESULTS: This was a post hoc analysis of 79 patients with acute HF included in the EMPA-RESPONSE-AHF trial, which compared sodium-dependent glucose-cotransporter protein 2 inhibitor treatment with empagliflozin for 30 days with placebo in patients with acute HF [NCT03200860]. Plasma concentrations of ketone bodies acetone, ß-hydroxybutyrate, and acetoacetate were measured at baseline and 5 different timepoints. Changes in ketone bodies over time were monitored using repeated measures analysis of variance. In the total cohort, median total ketone body concentration was 251 µmol/L (interquartile range, 178-377 µmol/L) at baseline, which gradually decreased to 202 µmol/L (interquartile range, 156-240 µmol/L) at day 30 (P = .041). Acetone decreased from 60 µmol/L (interquartile range, 34-94 µmol/L) at baseline to 30 µmol/L (interquartile range, 21-42 µmol/L) ( P < .001), whereas ß-hydroxybutyrate and acetoacetate remained stable over time. Higher acetone concentrations were correlated with higher N-terminal pro brain natriuretic peptide levels (r = 0.234; P = .039). Circulating ketone bodies did not differ between patients treated with empagliflozin or placebo throughout the study period. A higher acetone concentration at baseline was univariately associated with a greater risk of the composite end point, including in-hospital worsening HF, HF rehospitalizations, and all-cause mortality after 30 days. However, after adjustment for age and sex, acetone did not remain an independent predictor for the combined end point. CONCLUSIONS: Circulating ketone body concentrations, and acetone in particular, were significantly higher during an episode of acute decompensated HF compared with after stabilization. Treatment with empagliflozin did not affect ketone body concentrations in patients with acute HF.

GlycA, a novel pro-inflammatory glycoprotein biomarker is associated with mortality: results from the PREVEND study and meta-analysis.

BACKGROUND: Chronic diseases are associated with an inflammatory response. We determined the association of two inflammatory markers, GlycA and high-sensitivity C-reactive protein (hsCRP), with overall and cause-specific mortality in a cohort of men and women. METHODS: Cox regression analyses were used to examine associations of GlycA and hsCRP with all-cause, cancer and cardiovascular mortality in 5526 subjects (PREVEND cohort; average follow-up 12.6 years). RESULTS: GlycA was associated with all-cause mortality (n = 838), independent of clinical risk factors and hsCRP (hazard ratio 1.43 [95% confidence interval (CI): 1.09-1.87] for top versus bottom quartiles). For hsCRP, the association with all-cause mortality was nonsignificant after adjustment for GlycA. GlycA and hsCRP were associated with cancer mortality in men (n = 248), but not in women (n = 132). Neither GlycA nor hsCRP was independently associated with cardiovascular mortality (n = 201). In a meta-analysis of seven population-based studies, including 8153 deaths, the pooled multivariable-adjusted relative risk of GlycA for all-cause mortality was 1.74 (95% CI: 1.40-2.17) for top versus bottom quartiles. The association of GlycA with all-cause mortality was somewhat stronger than that of hsCRP. GlycA and hsCRP were not independently associated with cardiovascular mortality. The associations of GlycA and hsCRP with cancer mortality were present in men, but not in women. CONCLUSIONS: GlycA is significantly associated with all-cause mortality. GlycA and hsCRP were each not independently associated with cardiovascular mortality. The association of GlycA and hsCRP with cancer mortality appears to be driven by men.

Tumor Necrosis Factor-α is Inversely Related to Free Thyroxine in Euthyroid Subjects Without Diabetes.

Lower thyroid functional status within the euthyroid range may confer increased atherosclerosis susceptibility, as evidenced by increased intima media thickness and coronary artery calcification. Associations of lower thyroid functional status with pro-atherogenic (inflammatory) biomarkers may also extend into the euthyroid range. Here we established relationships of plasma tumor necrosis factor-α (TNF-α) with thyroid stimulating hormone (TSH) and free thyroxine (free T4) in euthyroid subjects with and without Type 2 diabetes mellitus (T2DM). Fasting TSH, free T4, and TNF-α were measured in 81 nondiabetic subjects and in 73 T2DM subjects with Type 2 diabetes mellitus (T2DM; insulin using subjects were excluded) with TSH and free T4 levels each within the institutional reference ranges. TSH was similar and free T4 was slightly higher in T2DM (p<0.016). Plasma TNF-α was increased in T2DM (p=0.007). In nondiabetic subjects, TNF-α was correlated inversely with free T4 (r=-0.254, p=0.022), whereas such a relationship was absent in T2DM subjects (r=0.058, p=0.63). Multivariable linear regression analysis showed that in nondiabetic subjects TNF-α remained inversely associated with free T4 after adjustment for age and sex (ß=-0.243, p=0.032) and additionally for thyroid autoantibodies (ß=-0.251, p=0.027), contrasting the lack of relationship in T2DM subjects (interaction: p=0.053). In T2DM subjects, TNF-α was also unrelated to free T4 taking account of possible confounders, as well as after exclusion of subjects using metformin or antihypertensive medication. In conclusion, higher levels of TNF-α relate to lower free T4. Low-normal thyroid function could influence pro-inflammatory pathways. This relationship appears to be disturbed in T2DM.

Higher Plasma ApoE Levels are Associated with Low-Normal Thyroid Function: Studies in Diabetic and Nondiabetic Subjects.

Low-normal thyroid function within the euthyroid range may confer higher plasma triglycerides, but relationships with plasma apolipoprotein (apo) E, which plays an important role in the metabolism of triglyceride-rich apoB-containing lipoproteins, are unknown. We determined relationships of plasma apoE with thyroid stimulating hormone (TSH) and free thyroxine (free T4) in euthyroid subjects with and without Type 2 diabetes mellitus (T2DM). TSH, free T4, lipids, and apoE were measured in fasting plasma from 72 T2DM subjects and 82 nondiabetic subjects. The APOE genotype was also determined. Free T4 was slightly higher in T2DM (p=0.030), but TSH levels were not different vs. nondiabetic subjects. The APOE genotype distribution was not different between the groups. None of the participants had the ε2/ε2 genotype. Plasma triglycerides were higher in T2DM (p=0.037). ApoB and apoE levels were not different between the groups. In all subjects combined, multivariable analysis showed that plasma triglycerides (p=0.039), non-high density lipoprotein (non-HDL) cholesterol (p=0.030), and apoE levels (p=0.002) were each independently and positively associated with TSH after adjustment for age, sex, T2DM and the presence of the APOE ε3 allele. Furthermore, the associations of TSH with apoE remained present after adjustment for either triglycerides, non-HDL cholesterol, or apoB (p=0.005 to 0.023). The presence of T2DM did not modify the relationships of TSH with these (apo) lipoprotein variables (p=0.11 to 0.36). In conclusion, low-normal thyroid function, as indicated by higher TSH levels within the euthyroid range, may influence the metabolism of triglyceride-rich lipoproteins by affecting apoE regulation.

Plasma phospholipid transfer protein activity is inversely associated with betaine in diabetic and non-diabetic subjects.

BACKGROUND: The choline metabolite, betaine, plays a role in lipid metabolism, and may predict the development of cardiovascular disease and type 2 diabetes mellitus (T2DM). Phospholipid transfer protein (PLTP) and lecithin:cholesterol acyltransferase (LCAT) require phosphatidylcholine as substrate, raising the possibility that there is an intricate relationship of these protein factors with choline metabolism. Here we determined the relationships of PLTP and LCAT activity with betaine in subjects with and without T2DM. METHODS: Plasma betaine (nuclear magnetic resonance spectroscopy), PLTP activity (liposome-vesicle HDL system), LCAT activity (exogenous substrate assay) and (apo)lipoproteins were measured in 65 type 2 diabetic (T2DM) and in 55 non-diabetic subjects. RESULTS: PLTP and LCAT activity were elevated in T2DM (p < 0.05), whereas the difference in betaine was not significant. In age-, sex- and diabetes status-controlled correlation analysis, betaine was inversely correlated with triglycerides and positively with HDL cholesterol (p < 0.05 to 0.01). PLTP and LCAT activity were positively correlated with triglycerides and inversely with HDL cholesterol (p < 0.05 to 0.001). PLTP (r = -0.245, p = 0.006) and LCAT activity (r = -0.195, p = 0.035) were correlated inversely with betaine. The inverse association of PLTP activity with betaine remained significant after additional adjustment for body mass index and lipoprotein variables (ß = -0.179, p = 0.034), whereas its association with LCAT activity lost significance (ß = -0.056, p = 0.44). CONCLUSIONS: Betaine may influence lipoprotein metabolism via an effect on PLTP activity.

Hepatic syndecan-1 changes associate with dyslipidemia after renal transplantation.

Syndecan-1 is a transmembrane heparan sulfate (HS) proteoglycan present on hepatocytes and involved in uptake of triglyceride-rich lipoproteins via its HS polysaccharide side chains. We hypothesized that altered hepatic syndecan-1 metabolism could be involved in dyslipidemia related to renal transplantation. In a rat renal transplantation model elevated plasma triglycerides were associated with fivefold increased expression of hepatic syndecan-1 mRNA (p < 0.01), but not protein. Expression of syndecan-1 sheddases (ADAM17, MMP9) and heparanase was significantly up-regulated after renal transplantation (all p < 0.05). Profiling of HS side chains revealed loss of hepatic HS upon renal transplantation accompanied by significant decreased functional capacity for VLDL binding (p = 0.02). In a human renal transplantation cohort (n = 510), plasma levels of shed syndecan-1 were measured. Multivariate analysis showed plasma syndecan-1 to be independently associated with triglycerides (p < 0.0001) and inversely with HDL cholesterol (p < 0.0001). Last, we show a physical association of syndecan-1 to HDL from renal transplant recipients (RTRs), but not to HDL from healthy controls. Our data suggest that after renal transplantation loss of hepatic HS together with increased syndecan-1 shedding hampers lipoprotein binding and uptake by the liver contributing to dyslipidemia. Our data open perspectives toward improvement of lipid profiles by targeted inhibition of syndecan-1 catabolism in renal transplantation.

Type 2 diabetes mellitus interacts with obesity and common variations in PLTP to affect plasma phospholipid transfer protein activity.

BACKGROUND: Phospholipid transfer protein (PLTP) is an emerging cardiometabolic risk marker that is important in high-density lipoprotein (HDL) and triglyceride metabolism. Plasma PLTP activity is elevated in type 2 diabetes mellitus, whereas glucose may regulate PLTP gene transcription in vitro. Of interest, common PLTP variations that predict cardiovascular disease have been identified recently. We investigated whether the diabetic state is able to amplify relationships between obesity and PLTP gene variations with circulating PLTP levels. SUBJECTS AND METHODS: Plasma PLTP activity (using a phospholipid vesicles-HDL system), PLTP gene score [number of PLTP activity-decreasing alleles based on two tagging polymorphisms (rs378114 and rs60- 65904)] and waist circumference were determined in two Dutch cohorts comprising 237 patients with type 2 diabetes and 78 control subjects. RESULTS: Patients with diabetes were more obese (P < 0.001 for prevalence of increased waist circumference) and had 13% higher plasma PLTP activity (P < 0.001). PLTP gene score was not different in diabetic and control subjects (P = 0.40). PLTP activity was highest in patients with diabetes with an enlarged waist and lowest in control subjects with a normal waist circumference (P < 0.001). Multiple linear regression analysis revealed a positive interaction between diabetes status and waist circumference on PLTP activity (ß = 0.200, P = 0.005). Furthermore, diabetes status (ß = -0.485, P = 0.046) or HbA1c (ß = -0.240, P = 0.035) interacted with PLTP gene score to affect PLTP activity. CONCLUSIONS: Type 2 diabetes and enlarged waist circumference interact to impact on plasma PLTP activity. Diabetes may also amplify the association between plasma PLTP activity and common PLTP gene variations. Our findings support the hypothesis that diabetes-environment and diabetes-gene interactions govern plasma PLTP activity.

Short term dietary sodium restriction decreases HDL cholesterol, apolipoprotein A-I and high molecular weight adiponectin in healthy young men: relationships with renal hemodynamics and RAAS activation.

BACKGROUND AND AIMS: We aimed to determine the effect of short-term dietary sodium restriction on plasma total cholesterol, LDL-C, HDL-C, triglycerides, apolipoprotein (apo) A-I, apo B and high molecular weight (HMW) adiponectin in non-obese, normotensive young men. Glomerular filtration rate (GFR), effective renal plasma flow (ERPF), plasma renin activity (PRA) and aldosterone were also measured. METHODS AND RESULTS: Sixty-five men, aged 23 ± 7 years, were randomly studied on a high sodium intake (HS, 228 ± 77 mmol Na+/24 h) and a low sodium intake (LS, 36 ± 27 mmol Na+/24 h), each period lasting 1 week. LS decreased GFR and ERPF and increased PRA and aldosterone (p < 0.0001 for all). LS also induced a decrease in HDL-C (3.8 ± 10.8%), apo A-I (3.7 ± 6.5%) and HMW-adiponectin (13.6 ± 40.5%) (p < 0.05 for all), but plasma total cholesterol, LDL-C, triglycerides and apo B did not significantly change. The changes in HDL-C and apo A-I were correlated negatively to the changes in effective renal plasma flow (p < 0.05), whereas the changes in HMW adiponectin were correlated negatively to the changes in PRA and aldosterone (p < 0.05 for both). CONCLUSION: Short term sodium restriction modestly decreases HDL-C, apo A-I and HMW-adiponectin in healthy men. Changes in GFR and ERPF and in the renin-angiotensin-aldosterone system as induced by LS may be involved in these responses.

Plasma lecithin: cholesterol acyltransferase activity modifies the inverse relationship of C-reactive protein with HDL cholesterol in nondiabetic men.

Lecithin:cholesterol acyltransferase (LCAT) is instrumental in high-density lipoprotein (HDL) maturation, but high LCAT levels do not predict low cardiovascular risk. LCAT may affect antioxidative or anti-inflammatory properties of HDL. We determined the relationship of plasma high-sensitivity C-reactive protein (CRP) with LCAT activity and evaluated whether LCAT activity modifies the decreasing effect of HDL cholesterol (HDL-C) on CRP, as an estimate of its anti-inflammatory properties. Plasma HDL-C, apolipoprotein (apo) A-I and LCAT activity (exogenous substrate method) were measured in 260 nondiabetic men without cardiovascular disease. CRP was correlated inversely with HDL-C and apo A-I, and positively with LCAT activity (P<0.01 to 0.001). Multivariate regression analysis demonstrated that age- and smoking-adjusted plasma CRP levels were associated negatively with HDL-C (beta=-0.224, P<0.001) and positively with LCAT activity (beta=0.119, P=0.034), as well as with the interaction between HDL-C and LCAT activity (beta=0.123, P=0.026). There was also an interaction between apo A-I and LCAT activity on CRP (beta=0.159, P=0.005). These relationships remained similar after adjustment for apo B-containing lipoproteins. In conclusion, the inverse relationship of HDL-C with CRP is attenuated by LCAT activity at higher HDL-C levels. It is hypothesized that LCAT could mitigate HDL's anti-inflammatory or antioxidative properties at higher HDL-C concentrations.

Apolipoprotein B/A-I and total cholesterol/high-density lipoprotein cholesterol ratios both predict cardiovascular events in the general population independently of nonlipid risk factors, albuminuria and C-reactive protein.

BACKGROUND: the total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C) and apolipoprotein (apo) B/A-I ratios predict major adverse cardiovascular events (MACEs). The extent to which these associations are modified by high-sensitivity C-reactive protein (hs-CRP) and albuminuria is largely unknown. We compared the strength of these ratios with first MACE in the general population and determined whether these associations remain when taking account of these risk markers. SUBJECTS AND METHODS: a prospective case-cohort study was performed among 6948 subjects (PREVEND cohort) without previous cardiovascular disease and who did not use lipid-lowering drugs initially. Fasting serum TC, low-density lipoprotein cholesterol (LDL-C), HDL-C, non-HDL-C, apoB, apoA-I, triglycerides, hs-CRP and albuminuria were measured at baseline. The composite endpoint was incident MACE. RESULTS: a total of 362 first cardiovascular events occurred during 7.9 years of follow-up. All pro- and anti-atherogenic measures of lipoproteins and apos predicted MACEs in age- and sex-adjusted Cox proportional hazard analyses (P = 0.018 to P < 0.001). The age- and sex-adjusted hazard ratio (HR) was 1.37 [95% confidence interval (CI), 1.26-1.48] for the apoB/apoA-I ratio and 1.24 (95% CI, 1.18-1.29) for the TC/HDL-C ratio (both P < 0.001). These relationships were essentially unaltered after additional adjustment for triglyceride levels. Pair-wise comparison revealed that these ratios were of similar importance in age- and sex-adjusted analysis (P = 0.397). The HRs of apoB/apoA-I (P < 0.001) and TC/HDL-C (P < 0.001) for risk of MACEs were only marginally attenuated by additional controlling for traditional risk factors (hypertension, diabetes, obesity and smoking), hs-CRP and albuminuria. CONCLUSIONS: first MACE is associated with both the fasting serum apoB/apoA-I ratio and the TC/HDL-C ratio in the general population, independently of triglycerides, hs-CRP and albuminuria.

Plasma pre beta-HDL formation is decreased by atorvastatin treatment in type 2 diabetes mellitus: Role of phospholipid transfer protein.

UNLABELLED: Atorvastatin lowers plasma phospholipid transfer protein (PLTP) activity, which stimulates pre-beta-HDL generation in vitro. We determined the effect of atorvastatin on pre-beta-HDL formation and its relation with PLTP activity in type 2 diabetes. METHODS: Plasma pre-beta-HDL formation as well as plasma apo A-I, LpA, LpAI:AII, cholesteryl ester transfer protein (CETP) and PLTP activity were measured before and after 30 weeks treatment in 40 patients randomized to atorvastatin 80 mg daily and 41 placebo receiving patients. Pre-beta HDL formation was measured by crossed immunoelectrophoresis under conditions of lecithin:cholesterol acyltransferase (LCAT) inhibition. RESULTS: Plasma pre-beta-HDL formation, triglycerides, LDL cholesterol, PLTP activity, and CETP decreased after statin treatment (all P<0.001 vs placebo), whereas HDL cholesterol increased (P<0.005). Plasma apo A-I, LpAI and LpAI:AII remained unchanged compared to placebo. In all patients combined, the changes in pre-beta-HDL formation were independently related to the decrease in plasma triglycerides (beta=0.31; P=0.006) and PLTP activity (beta=0.23; P=0.038), without a contribution of CETP. In the atorvastatin treated patients, the decrease in pre-beta-HDL formation tended to be related to the decrease in PLTP activity (beta=0.30, P=0.061) after controlling for decreases in triglycerides (beta=0.22, P=0.22). CONCLUSION: High dose atorvastatin decreases the capacity of plasma to generate pre-beta-HDL particles in type 2 diabetic patients, probably via lowering of plasma PLTP activity and triglycerides. This could contribute to an improvement in the atherogenic lipoprotein profile.

The ability of plasma to stimulate fibroblast cholesterol efflux is associated with the -629C-->A cholesteryl ester transfer protein promoter polymorphism: role of lecithin: cholesterol acyltransferase activity.

A recent population-based study showed that cholesteryl ester transfer protein (CETP) gene variations, which relate to lower plasma CETP, may predict increased cardiovascular risk, in spite of higher HDL cholesterol. Among other functions, CETP activity contributes to cellular cholesterol efflux, an early step in the anti-atherogenic reverse cholesterol transport (RCT) process. We hypothesized that cellular cholesterol efflux stimulating capacity of plasma could be associated with CETP gene variation. In this study, we tested the extent to which the ability of plasma to promote cholesterol efflux from cultured human fibroblasts is associated with CETP gene variation. In 223 men, the -629C-->A CETP promoter polymorphism, plasma lipids, CETP mass, cholesteryl ester transfer (CET), lecithin:cholesterol acyltransferase (LCAT) activity and the ability of plasma to promote cholesterol efflux from human skin fibroblasts, obtained from a single normolipidemic donor, were determined. In -629CC homozygotes (n=52), cholesterol efflux, plasma CETP mass, CET and LCAT activity were higher, whereas HDL cholesterol was lower compared to -629 AA homozygotes (n=62) and -629CA+AA carriers (n=171) (P<0.05 to P<0.001). Univariate correlation analysis showed that cellular cholesterol efflux was related to CETP genotype (P=0.04), plasma CET (P<0.05), LCAT activity (P<0.001) and apo A-I (P<0.05). Multiple linear regression analysis confirmed the independent association of cellular cholesterol efflux to plasma with CETP genotype. In conclusion, an association of cellular cholesterol efflux with the -629C-->A CETP polymorphism, possibly also involving LCAT activity, could provide a mechanism explaining why CETP gene variation, which relates to lower plasma CETP, does not confer diminished cardiovascular risk.

Apolipoprotein M predicts pre-beta-HDL formation: studies in type 2 diabetic and nondiabetic subjects.

OBJECTIVE: Studies in mice suggest that plasma apoM is lowered in hyperinsulinaemic diabetes and that apoM stimulates formation of pre-beta-HDL. Pre-beta-HDL is an acceptor of cellular cholesterol and may be critical for reverse cholesterol transport. Herein, we examined whether patients with type 2 diabetes have reduced plasma apoM and whether apoM is associated with pre-beta-HDL formation and cellular cholesterol efflux. DESIGN: In 78 patients with type 2 diabetes and 89 control subjects, we measured plasma apoM with ELISA, pre-beta-HDL and pre-beta-HDL formation, phospholipid transfer protein (PLTP) activity and the ability of plasma to promote cholesterol efflux from cultured fibroblasts. RESULTS: ApoM was approximately 9% lower in patients with type 2 diabetes compared to controls (0.025 +/- 0.006 vs. 0.027 +/- 0.007 g L(-1), P = 0.01). The difference in apoM was largely attributable to diabetes-associated obesity. ApoM was positively related to both HDL (r = 0.16; P = 0.04) and LDL cholesterol (r = 0.28; P = 0.0003). Pre-beta-HDL and pre-beta-HDL formation were not different between diabetic and control subjects. ApoM predicted pre-beta-HDL (r = 0.16; P = 0.04) and pre-beta-HDL formation (r = 0.19; P = 0.02), even independently of positive relationships with apoA-I, HDL-cholesterol and PLTP activity. Cellular cholesterol efflux to plasma was positively related to pre-beta-HDL and PLTP activity but not significantly to apoM. CONCLUSIONS: Plasma apoM is modestly reduced in type 2 diabetes. Pre-beta-HDL and pre-beta-HDL formation are positively associated with apoM, supporting the hypothesis that apoM plays a role in HDL remodelling in humans. Lower apoM may provide a mechanism to explain why pre-beta-HDL formation is not increased in type 2 diabetes despite elevated PLTP activity.

Serum paraoxonase-I activity is unaffected by short-term administration of simvastatin, bezafibrate, and their combination in type 2 diabetes mellitus.

BACKGROUND: The high-density lipoprotein (HDL)-associated anti-oxidative and anti-inflammatory enzyme, paraoxonase-I, has been found previously to be lower in type 2 diabetes mellitus. We studied whether statin and fibrate treatment, alone and in combination, affect serum paraoxonase-I activity in conjunction with changes in HDL cholesterol in diabetic patients. SUBJECTS AND METHODS: A placebo-controlled crossover study was carried out in 14 type 2 diabetic patients to test the effect of 8 weeks of active treatment with simvastatin (40 mg daily), bezafibrate (400 mg daily), and their combination on serum paraoxonase-I activity, measured as its activity towards arylesterase and paraoxon. Serum paraoxonase-I activity was also compared between these diabetic patients and 49 non-diabetic control subjects. RESULTS: Serum arylesterase activity was lower in type 2 diabetic patients compared to control subjects (P < 0.001), but the difference in paraoxonase activity was not significant (P = 0.22). Neither arylesterase (P = 0.24) nor paraoxonase activity (P = 0.37) was increased in response to treatment, despite higher HDL cholesterol and apolipoprotein A-I during combination therapy (P < 0.05 for both). CONCLUSION: Short-term administration of simvastatin and bezafibrate, even when combined, is ineffective in raising serum paraoxonase-I activity in type 2 diabetes.

Plasma cholesteryl ester transfer protein mass and phospholipid transfer protein activity are associated with leptin in type 2 diabetes mellitus.

Adipose tissue contributes to plasma levels of lipid transfer proteins and is also the major source of plasma adipokines. We hypothesized that plasma cholesteryl ester transfer protein (CETP) mass, phospholipid transfer protein (PLTP) activity and cholesteryl ester transfer (CET, a measure of CETP action) are determined by adipokine levels. In this study, relationships of plasma CETP mass, PLTP activity and CET with leptin, resistin and adiponectin were analyzed in type 2 diabetic patients and control subjects. Plasma PLTP activity (P<0.001), CET (P<0.001), leptin (P=0.003), resistin (P<0.001), high sensitive C-reactive protein (P=0.005), and insulin resistance (HOMA(ir)) (P<0.001) were higher, whereas HDL cholesterol (P<0.001) and plasma adiponectin (P<0.001) were lower in 83 type 2 diabetic patients (32 females) than in 83 sex-matched control subjects. Multiple linear regression analysis demonstrated that in diabetic patients plasma leptin levels were related to plasma CETP mass (P=0.018) and PLTP activity (P<0.001), but not to the other adipokines measured. Plasma CET was inversely correlated with adiponectin in univariate analysis, but this association disappeared in multivariate models that included plasma lipids and CETP. In conclusion, both plasma CETP mass and PLTP activity are associated with plasma leptin in type 2 diabetes. The elevated CET in these patients is not independently related to any of the measured plasma adipokines.

Malignant aldosterone-producing adrenal tumour: reoccurrence with glucocorticoid excess without hyperaldosteronism.

We describe a case of hypokalaemic hypertension due to hyperaldosteronism caused by a unilateral adrenocortical tumour with unfavourable histopathology suggestive of malignancy. After removal, the aldosterone excess disappeared. The patient's clinical course was uneventful, until she presented with extensive metastases of adrenal carcinoma four years later. Biochemical abnormalities were now consistent with glucocorticoid excess without hyperaldosteronism. She died four months later. Although malignant aldosterone-producing adrenal tumours are very rare, the present case underscores that clinicians should be aware that primary hyperaldosteronism can occur in the context of adrenocortical carcinoma.

Cyclic Cushing's syndrome: a clinical challenge.

Cyclic Cushing's syndrome (CS) is a rare disorder, characterized by repeated episodes of cortisol excess interspersed by periods of normal cortisol secretion. The so-called cycles of hypercortisolism can occur regularly or irregularly with intercyclic phases ranging from days to years. To formally diagnose cyclic CS, three peaks and two troughs of cortisol production should be demonstrated. Our review of 65 reported cases demonstrates that cyclic CS originates in 54% of cases from a pituitary corticotroph adenoma, in 26% from an ectopic ACTH-producing tumour and in about 11% from an adrenal tumour, the remainder being unclassified. The pathophysiology of cyclic CS is largely unknown. The majority of patients with cyclic CS have clinical signs of CS, which can be either fluctuating or permanent. In a minority of patients, clinical signs of CS are absent. The fluctuating clinical picture and discrepant biochemical findings make cyclic CS extremely hard to diagnose. Clinicians should therefore be aware of this clinical entity and actively search for it in all patients with suspected CS but normal biochemistry or vice versa. Frequent measurements of urinary cortisol or salivary cortisol levels are a reliable and convenient screening tool for suspected cyclic CS. Cortisol stimulation or suppression tests may give spurious results owing to spontaneous falls or rises in serum cortisol at the time of testing. When cyclic CS is biochemically confirmed, further imaging and laboratory studies are guided by the presence or absence of ACTH dependency. In cases of suspected ectopic ACTH production, specific biochemical testing for carcinoids or neuroendocrine tumours is required, including measurements of serotonin in platelets and/or urine, chromogranin A and calcitonin.

Mediastinal emphysema complicating diabetic ketoacidosis: plea for conservative diagnostic approach.

BACKGROUND: Spontaneous pneumomediastinum has been infrequently reported as a complication of diabetic ketoacidosis. Evidence-based guidelines are currently not available to help in choosing the best diagnostic approach. METHODS: We conducted a systematic review of the literature and looked for diagnostic clues that might indicate the need for a work-up to rule out oesophageal perforation. RESULTS: In all 56 published cases of spontaneous pneumomediastinum associated with diabetic ketoacidosis, the condition was self-limiting. We report one additional case of a 31-year-old female who presented with a spontaneous pneumomediastinum and also epidural pneumatosis, complicating diabetic ketoacidosis. CONCLUSION: Important pathology, such as oesophageal rupture, was not detected in any of the reported cases, and we suggest a restrictive diagnostic work-up.

Treatment with intramuscular vascular endothelial growth factor gene compared with placebo for patients with diabetes mellitus and critical limb ischemia: a double-blind randomized trial.

Despite advances in revascularization techniques, limb salvage and relief of pain cannot be achieved in many diabetic patients with diffuse peripheral vascular disease. Our objective was to determine the effect of intramuscular administration of phVEGF165 (vascular endothelial growth factor gene-carrying plasmid) on critical limb ischemia (CLI) compared with placebo (0.9% NaCl). A double-blind, placebo-controlled study was performed in 54 adult diabetic patients with CLI. The primary end point was the amputation rate at 100 days. Secondary end points were a 15% increase in pressure indices (ankle-to-brachial index and toe-to-brachial index), clinical improvement (skin, pain, and Quality of Life score), and safety. In patients (n=27) treated with placebo versus phVEGF165-treated patients (n=27) the following results were found: 6 amputations versus 3 (p=not significant [NS]); hemodynamic improvement in 1 versus 7 (p=0.05); improvement in skin ulcers, 0 versus 7 (p=0.01); decrease in pain, 2 versus 5 (p=NS); and overall, 3 versus 14 responding patients (p=0.003). No grade 3 or 4 adverse effects were seen in these patients. We conclude that this small, randomized gene therapy study failed to meet the primary objective of significant amputation reduction. However, significant and meaningful improvement was found in patients treated with a VEGF165-containing plasmid. There were no substantial adverse events.