MiR-205 is up-regulated in islets of diabetes-susceptible mice and targets the diabetes gene Tcf7l2.

AIM: MicroRNAs play an important role in the maintenance of cellular functions by fine-tuning gene expression levels. The aim of the current study was to identify genetically caused changes in microRNA expression which associate with islet dysfunction in diabetic mice. METHODS: To identify novel microRNAs involved in islet dysfunction, transcriptome and miRNome analyses were performed in islets of obese, diabetes-susceptible NZO and diabetes-resistant B6-ob/ob mice and results combined with quantitative trait loci (QTL) and functional in vitro analysis. RESULTS: In islets of NZO and B6-ob/ob mice, 94 differentially expressed microRNAs were detected, of which 11 are located in diabetes QTL. Focusing on conserved microRNAs exhibiting the strongest expression difference and which have not been linked to islet function, miR-205-5p was selected for further analysis. According to transcriptome data and target prediction analyses, miR-205-5p affects genes involved in Wnt and calcium signalling as well as insulin secretion. Over-expression of miR-205-5p in the insulinoma cell line INS-1 increased insulin expression, left-shifted the glucose-dependence of insulin secretion and supressed the expression of the diabetes gene TCF7L2. The interaction between miR-205-5p and TCF7L2 was confirmed by luciferase reporter assay. CONCLUSION: MiR-205-5p was identified as relevant microRNA involved in islet dysfunction by interacting with TCF7L2.

Polymorphisms in miRNA binding sites involved in metabolic diseases in mice and humans.

Type 2 diabetes and obesity are well-studied metabolic diseases, which are based on genetic and epigenetic alterations in combination with an obesogenic lifestyle. The aim of this study was to test whether SNPs in miRNA-mRNA binding sites that potentially disrupt binding, elevate the expression of miRNA targets, which participate in the development of metabolic diseases. A computational approach was developed that integrates transcriptomics, linkage analysis, miRNA-target prediction data, and sequence information of a mouse model of obesity and diabetes. A statistical analysis demonstrated a significant enrichment of 566 genes for a location in obesity- and diabetes-related QTL. They are expressed at higher levels in metabolically relevant tissues presumably due to altered miRNA-mRNA binding sites. Of these, 51 genes harbor conserved and impaired miRNA-mRNA-interactions in human. Among these, 38 genes have been associated to metabolic diseases according to the phenotypes of corresponding knockout mice or other results described in the literature. The remaining 13 genes (e.g. Jrk, Megf9, Slfn8 and Tmem132e) could be interesting candidates and will be investigated in the future.

Reduced insulin clearance is linked to subclinical atherosclerosis in individuals at risk for type 2 diabetes mellitus.

Hyperglycemia and insulin resistance contribute to vascular damage and are regulated by different pathophysiological processes. The aim of the study was to systematically investigate the relative contributions of multiple fasting state- and oral glucose tolerance test (oGTT)-derived glycemic traits to carotid intima-media thickness (cIMT), a surrogate parameter of subclinical atherosclerosis, in individuals with increased risk for type 2 diabetes mellitus (T2D). 667 volunteers (417 women and 250 men, mean age 44.1 years), who were free of cardiovascular disease (CVD), were included in this cross-sectional study. Glucose tolerance, insulin sensitivity, insulin secretion and insulin clearance were assessed by frequently sampled 75 g oGTT. CIMT was measured by high-resolution ultrasound. Insulin clearance was associated with cIMT in univariate analysis (ßst = - 0.17, p < 0.0001) and in a stepwise regression analysis on 15 variables possibly affecting cIMT, age (r2 = 0.3923, p < 0.0001), insulin clearance (r2 = 0.4564, p < 0.0001), systolic blood pressure (r2 = 0.4733, p < 0.0001), body mass index (BMI) (r2 = 0.4804, p = 0.002), gender (r2 = 0.4831, p = 0.013), and fasting insulin clearance (r2 = 0.4857, p = 0.030) turned out to be significant determinants of cIMT. In a cross-validated model resulting from this analysis, insulin clearance was found to be an independent determinant of cIMT (ßst = - 0.16, p < 0.0001) even after adjusting for traditional CVD risk factors. Reduced insulin clearance may be an early marker of damage on the vasculature, independent of classical CVD risk factors. Reduced insulin clearance should be considered with regard to vascular insulin resistance.

Visceral Adiposity Index as an Independent Marker of Subclinical Atherosclerosis in Individuals Prone to Diabetes Mellitus.

AIM: The visceral adiposity index (VAI) has been proposed as an estimate of visceral adipose tissue (VAT) mass and as an indicator of VAT dysfunction. Both parameters are associated with cardiometabolic risk, including insulin resistance. In this study, we investigated whether VAI is associated with subclinical atherosclerosis in subjects who were free of cardiovascular disease but were at risk of developing diabetes mellitus. METHODS: A total of 731 adults with a median age of 47 years old without diabetes mellitus were included in this cross-sectional study. The anthropometric data, blood pressure, and lipid profiles of 398 women and 333 men were measured. All subjects underwent an oral glucose tolerance test, and carotid intima-media thickness (cIMT) was evaluated by ultrasound. Insulin resistance was estimated using the homeostatic model assessment of insulin resistance (HOMA-IR). RESULTS: VAI and HOMA-IR (ßst=0.44, p＜0.0001), VAI and cIMT (ßst=0.17, p＜0.0001), and HOMA-IR and cIMT (ßst=0.09, p=0.0127) were correlated with each other. After adjusting for cofounding variables, VAI is still correlated with HOMA-IR (ßst=0.42, p＜0.0001). Furthermore, VAI (ßst=0.07, p=0.0392) but not HOMA-IR (ßst=0.03, p=0.37) was correlated with cIMT independently of other established cardiovascular risk factors. CONCLUSION: The calculation of VAI may provide a better estimation of subclinical atherosclerosis than the calculation of HOMA-IR.

Periaortic Adipose Tissue Compared With Peribrachial Adipose Tissue Mass as Markers and Possible Modulators of Cardiometabolic Risk.

Increased perivascular fat mass contributes to cardiometabolic risk (CMR). High peribrachial adipose tissue (PBAT) associates with insulin resistance independently of established CMR parameters. It is unknown to what extent periaortic adipose tissue (PAAT) may have a similar impact. In 95 participants, precise quantification of total adipose tissue, PBAT, PAAT, visceral adipose tissue (VAT), and liver fat (LF) content was performed by whole-body magnetic resonance imaging. Insulin sensitivity was determined by oral glucose tolerance test and carotid intima-media thickness (cIMT) by high-resolution ultrasound. In univariate analyses, PAAT correlated with PBAT (ß = .65, P < .0001). A negative correlation of PAAT (ß = -.35, P = .0002) and PBAT (ß = -.43, P < .0001) with insulin sensitivity was observed. While in a stepwise forward regression analysis the relationship of PAAT with insulin sensitivity was no longer significant after adjustment for VAT, LF content, and other CMR factors ( P = 0.42), PBAT still correlated with insulin sensitivity ( r2 = .35, P = .01). The association between PAAT and cIMT (ß = .49, P < .0001) remained significant after adjustment for these variables ( r2 = .42, P = .0001). Although PAAT and PBAT strongly correlate, PAAT is not associated with insulin resistance, but with cIMT. Therefore, PAAT and PBAT may act differently as possible modulators of insulin resistance and subclinical atherosclerosis.

[Thromboembolic complication after ovarian stimulation]. / Thromboembolische Komplikation nach ovarieller Stimulation--Fall 1/2016.

HISTORY AND ADMISSION FINDINGS: We report on two pregnant women with dyspnoe and thoracic pain in the context of an ovarian hyperstimulation syndrome. INVESTIGATIONS: Both patients had pleural effusions. The first patient was diagnosed with pulmonary embolism via computer tomography. In the second patient, thrombosis of the upper part of the body including intracranial thrombosis was revealed via magnetic resonance and ultrasound imaging. In both cases, thrombosis was caused by ovarian hyperstimulation. DIAGNOSIS, TREATMENT AND COURSE: Therapy included anticoagulation with low molecular weight heparin and a drainage of the pleural effusions. One patient had an abortion in the 8th week of pregnancy, the second patient gave birth to two healthy children. CONCLUSIONS: Ovarian hyperstimulation syndrome is a potentially life-threatening disease, which should be considered as a differential diagnosis of causes of thromboembolic events in early pregnancy.

Normal values for intima-media thickness of the common carotid artery--an update following a novel risk factor profiling.

BACKGROUND: There is a widely approved influence of novel risk factors like the body fat distribution and the associated metabolic syndrome, subclinical inflammation, insulin resistance and prediabetic disturbances in glucose metabolism on the progression of atherosclerosis. Former studies examining normal values for intima-media thickness (IMT) did not consider all of these new study results in detail. We therefore aimed to assess an update on age- and gender-specific normal values for IMT accounting for these novel risk factors. PATIENTS AND METHODS: We evaluated IMT by high-resolution ultrasound (13 MHz) on the far wall of the common carotid artery in 801 subjects without cardiovascular disease (428 women aged 46.2±12.9 years; 373 men aged 47.3±13.3 years). After precise evaluation and exclusion of 14 cardiovascular risk factors, 90% limits of IMT were determined by parametric statistics. RESULTS: The reference limits of IMT according to the age classes 18-29, 30-39, 40-49 and 50-59 years were estimated as 0.47, 0.59, 0.67 and 0.70 mm in women and 0.47, 0.62, 0.72 and 0.80 mm in men. CONCLUSIONS: Age and gender-specific normal values for IMT are lower than reported in former studies after additionally accounting for novel cardiovascular risk factors. The still widely regarded upper IMT limit of 1 mm must be strictly regarded as obsolete.

[Rare cause of an abdominal emergency--case 6/2014]. / Seltene Ursache eines akuten Abdomens--Fall 6/2014.

HISTORY AND ADMISSION FINDINGS: We report on a 58-year-old male patient with abdominal and right-sided flank pain, who presented with the picture of an acute abdominal emergency. INVESTIGATIONS: Laboratory tests revealed evidence of an inflammation and a hematuria. In the Doppler duplex ultrasound and computed tomography, chronic idiopathic periaortitis was diagnosed. The inflammatory-fibrosing disease resulted in urine retention and rupture of the fornix of the right kidney. DIAGNOSIS, TREATMENT AND COURSE: After surgical implementation of an ureteral stent and initiation of immunosuppressive therapy, it came to an improvement of the symptoms. CONCLUSIONS: In the differential diagnosis of an acute abdominal emergency, diseases of the aorta should be taken into account. Especially in male patients with anatomical complications it is important to exclude an inflammatory-fibrosing disease.

Fetuin-A influences vascular cell growth and production of proinflammatory and angiogenic proteins by human perivascular fat cells.

AIMS/HYPOTHESIS: Fetuin-A (alpha2-Heremans-Schmid glycoprotein), a liver-derived circulating glycoprotein, contributes to lipid disorders, diabetes and cardiovascular diseases. In a previous study we found that perivascular fat cells (PVFCs) have a higher angiogenic potential than other fat cell types. The aim was to examine whether fetuin-A influences PVFC and vascular cell growth and the expression and secretion of proinflammatory and angiogenic proteins, and whether TLR4-independent pathways are involved. METHODS: Mono- and co-cultures of human PVFCs and endothelial cells were treated with fetuin-A and/or palmitate for 6-72 h. Proteins were quantified by ELISA and Luminex, mRNA expression by real-time PCR, and cell growth by BrDU-ELISA. Some PVFCs were preincubated with a nuclear factor κB NFκBp65 inhibitor, or the toll-like receptor 4 (TLR4) inhibitor CLI-095, or phosphoinositide 3-kinase (PI3K)/Akt inhibitors and/or stimulated with insulin. Intracellular forkhead box protein O1 (FoxO1), NFκBp65 and inhibitor of κB kinase ß (IKKß) localisation was visualised by immunostaining. RESULTS: PVFCs expressed and secreted IL-6, IL-8, plasminogen activator inhibitor 1 (PAI-1), basic fibroblast growth factor (bFGF), platelet-derived growth factor (PDGF)-BB, monocyte chemotactic protein-1 (MCP-1), vascular endothelial growth factor (VEGF), placental growth factor (PLGF) and hepatocyte growth factor (HGF). Fetuin-A upregulated IL-6 and IL-8, and this was potentiated by palmitate and blocked by CLI-095. Immunostaining and electrophoretic mobility shift assay (EMSA) showed partial NFκBp65 activation. MCP-1 was upregulated and blocked by CLI-095, but not by palmitate. However, HGF was downregulated, which was slightly potentiated by palmitate. This effect persisted after TLR4 pathway blockade. Stimulation of insulin-PI3K-Akt signalling by insulin resulted in nuclear FoxO1 extrusion and HGF upregulation. Fetuin-A counteracted these insulin effects. CONCLUSIONS/INTERPRETATION: Fetuin-A and/or palmitate influence the expression of proinflammatory and angiogenic proteins only partially via TLR4 signalling. HGF downregulation seems to be mediated by interference with the insulin-dependent receptor tyrosine kinase pathway. Fetuin-A may also influence angiogenic and proinflammatory proteins involved in atherosclerosis.

Perfusion measurements of the calf in patients with peripheral arterial occlusive disease before and after percutaneous transluminal angioplasty using MR arterial spin labeling.

PURPOSE: To evaluate muscle perfusion in patients with peripheral arterial occlusive disease (PAOD) before and after percutaneous transluminal angioplasty (PTA) of the limb by means of MR arterial spin labeling (ASL) perfusion measurements during reactive hyperemia. MATERIALS AND METHODS: Ten patients with symptomatic PAOD affecting the iliac or femoral vessels were investigated before and after PTA. A pseudo-continuous arterial spin labeling (PCASL) MR technique was applied. Perfusion was measured in soleus and tibialis anterior muscle during reactive hyperemia. Key parameters such as mean perfusion value (Phyp ), time-to-peak (TTP) and duration of hyperemia (Thyp ) describing the perfusion signal curve were examined. RESULTS: Between baseline and post-PTA, Phyp increased in both muscle groups. At the same time, TTP and Thyp decreased in both muscle groups. At the same time the clinically assessed ankle brachial index (ABI) increased from 0.56 ± 0.10 to 0.83 ± 0.15. The impaired pain-free walking distance improved in all patients. CONCLUSION: PCASL MRI can detect changes of the key perfusion parameters Phyp , TTP, and Thyp after successful PTA of the calf muscles during reactive hyperemia and seems to be a promising tool for monitoring of interventional treatments.

Management of disseminated intravascular coagulopathy with direct factor Xa inhibitor rivaroxaban in Klippel-Trénaunay syndrome.

Klippel-Trénaunay syndrome (KTS) is a rare congenital anomaly characterized by malformation of lymph and blood vessels as well as growth disturbance of soft tissue and bone. The clinical picture is variable and associated with an increased risk of thromboembolic events mediated by intravascular coagulopathy in venous malformations. Here, we report on a male patient with KTS suffering from recurrent deep vein thrombosis (DVT) and life-threatening bleeding due to consumptive coagulopathy. Furthermore, we describe the successful long-term anticoagulant management with rivaroxaban.

[Thrombosis of the pelvic and leg--conservative procedure or thrombolytic therapy?]. / Becken-Beinvenenthrombose--konservatives Vorgehen oder Lysetherapie?

HISTORY AND ADMISSION FINDINGS: We report on a young female patient with flank pain and a swelling of the lower limb of the left side. INVESTIGATIONS: In magnetic resonance angiography as well as Doppler-duplex ultrasound an iliofemoral phlebothrombosis of the left side due to vena cava inferior hypoplasia with collateral circulation was diagnosed. Oral contraception could play a role as a trigger. The patient also presented activated protein C resistance/ heterozygous factor V Leiden mutation. DIAGNOSIS, TREATMENT AND COURSE: According to the CaVenT study we treated the patient successfully with catheter-directed thrombolysis. Follow-ups presented a patency of the iliofemoral vein. CONCLUSIONS: In young patients with short duration of a proximal deep vein thrombosis and after exclusion of contraindications a catheter-directed lysis should be considered as a treatment option. The differential diagnostic of a (bilateral) ilio-femoral vein thrombosis in young patients should include an anomaly of the venous system.

4-1BB ligand modulates direct and Rituximab-induced NK-cell reactivity in chronic lymphocytic leukemia.

NK cells play an important role in tumor immunosurveillance and largely contribute to the therapeutic success of anti-tumor antibodies like Rituximab. Here, we studied the role of the TNF family member 4-1BB ligand (4-1BBL) during the interaction of NK cells with chronic lymphocytic leukemia (CLL) cells. 4-1BBL was highly expressed on patient B-CLL cells in all 56 investigated cases. Signaling via 4-1BBL following interaction with 4-1BB, which was detected on NK cells of CLL patients but not healthy individuals, led to the release of immunoregulatory cytokines including TNF by CLL cells. CLL patient sera contained elevated levels of TNF and induced 4-1BB upregulation on NK cells, which in turn impaired direct and Rituximab-induced NK-cell reactivity against 4-1BBL-expressing targets. NK-cell reactivity was not only enhanced by blocking the interaction of NK cell-expressed 4-1BB with 4-1BBL expressed by CLL cells, but also by preventing 4-1BB upregulation on NK cells via neutralization of TNF in patient serum with Infliximab. Our data indicate that 4-1BBL mediates NK-cell immunosubversion in CLL, and thus might contribute to the reportedly compromised efficacy of Rituximab to induce NK-cell reactivity in the disease, and that TNF neutralization may serve to enhance the efficacy of Rituximab treatment in CLL.

Cardiorespiratory fitness determines the reduction in blood pressure and insulin resistance during lifestyle intervention.

OBJECTIVE: Lifestyle intervention is not always effective for improving arterial hypertension and other cardiovascular risk factors, and the parameters determining the outcome are not known. Because high cardiorespiratory fitness (CRF) protects from cardiovascular disease and mortality, we determined whether CRF at baseline predicts the improvement of blood pressure and other cardiovascular risk factors during a lifestyle intervention. METHODS: A total of 219 patients at risk for type 2 diabetes, who underwent a 9-month lifestyle intervention with diet modification and increase in physical activity, and had measurement of CRF, were studied. Insulin sensitivity was estimated during a 75-g oral glucose tolerance test. Total body, visceral and liver fat were measured by magnetic resonance (MR) tomography and H-MR spectroscopy. CRF was estimated using two different methods, an incremental cycle exercise (maximal aerobic capacity-VO2max) test and a motorized treadmill (individual anaerobic threshold) test. RESULTS: After 9 months of intervention adiposity, glycemia, CRF, insulin sensitivity, SBP and serum lipids (except high-density lipoprotein cholesterol, P = 0.65) improved (all other P ≤ 0.006). DBP did not change significantly (P = 0.06). High CRF at baseline predicted decreases in SBP (P ≤ 0.0002) and DBP (P ≤ 0.004), and increase in insulin sensitivity (P ≤ 0.04), but not change in serum lipids (all P ≥ 0.06). For 1 SD increase in baseline CRF the odds ratio for resolution of hypertension or prehypertension was 2.26 (individual anaerobic threshold; 95% CI 1.40-3.80) and 1.75 (VO2max; 95% CI 1.08-2.89). CONCLUSION: CRF at baseline predicts the effectiveness of a lifestyle intervention in improving insulin sensitivity, and particularly blood pressure.

Metabonomic fingerprints of fasting plasma and spot urine reveal human pre-diabetic metabolic traits.

Impaired glucose tolerance (IGT) which precedes overt type 2 diabetes (T2DM) for decades is associated with multiple metabolic alterations in insulin sensitive tissues. In an UPLC-qTOF-mass spectrometry-driven non-targeted metabonomics approach we investigated plasma as well as spot urine of 51 non-diabetic, overnight fasted individuals aiming to separate subjects with IGT from controls thereby identify pathways affected by the pre-diabetic metabolic state. We could clearly demonstrate that normal glucose tolerant (NGT) and IGT subjects clustered in two distinct groups independent of the investigated metabonome. These findings reflect considerable differences in individual metabolite fingerprints, both in plasma and urine. Pre-diabetes associated alterations in fatty acid-, tryptophan-, uric acid-, bile acid-, and lysophosphatidylcholine-metabolism, as well as the TCA cycle were identified. Of note, individuals with IGT also showed decreased levels of gut flora-associated metabolites namely hippuric acid, methylxanthine, methyluric acid, and 3-hydroxyhippuric acid. The findings of our non-targeted UPLC-qTOF-MS metabonomics analysis in plasma and spot urine of individuals with IGT vs NGT offers novel insights into the metabolic alterations occurring in the long, asymptomatic period preceding the manifestation of T2DM thereby giving prospects for new intervention targets. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11306-010-0203-1) contains supplementary material, which is available to authorized users.

Rapid effect of single-dose rosiglitazone treatment on endothelial function in healthy men with normal glucose tolerance: data from a randomised, placebo-controlled, double-blind study.

Antidiabetic thiazolidinediones (TZDs) improve endothelial function in patients with or without type 2 diabetes. The present randomised, placebo-controlled, double-blind study examined the time course of a single dose of rosiglitazone on flow-mediated endothelium-dependent vasodilation (FMD), metabolic parameters, and its effect on inflammatory markers in non-diabetic men. Forty non-obese, healthy men with normal glucose tolerance were randomised to a single dose of rosiglitazone (8 mg) or placebo, and FMD was assessed at baseline as well as after 6 h and 24 h. Rosiglitazone did not significantly affect blood glucose and insulin levels or lipid parameters after 6 and 24 h compared with placebo. Treatment with rosiglitazone significantly increased FMD after 6 h from 4.3% (3.3; 4.9) to 7.6% (5.6; 9.2) (p<0.0001 vs. baseline) resulting in a highly significant effect compared with placebo (p<0.0001 for difference between groups). After 24 h FMD was still significantly higher in the rosiglitazone group compared with baseline (p=0.001), but the effect was no longer statistically significant versus placebo (p=0.171). Our study shows a very rapid effect of single dose rosiglitazone treatment on endothelial function in non-diabetic healthy men, underscoring the hypothesis that TZDs may exhibit direct effect in the vasculature independent of their metabolic action.

Determination of unknown high-grade atherosclerotic lesions by whole-body cardiovascular imaging: assessment of patients with symptomatic atherosclerotic disease of peripheral arteries.

RATIONALE AND OBJECTIVES: The long-term prospects for patients with peripheral-arterial-occlusive disease (PAOD) must be considered in the context of coexistent generalized atherosclerosis. We sought to determine the added clinical information of noninvasive magnetic resonance imaging (MRI) for detecting asymptomatic atherosclerotic disease in patients already at high risk. MATERIALS AND METHODS: Eighty-four patients (64 men, mean age 66.2 + or - 10.0 years, range 34-84 years) with suspected or known PAOD were examined using a comprehensive cardiovascular MRI protocol. Two experienced observers reviewed all MRIs for the presence of "relevant findings," which were defined as pathology requiring immediate therapy or mid-term follow-up. RESULTS: Assessment of cardiac structures and function in 84 study patients yielded new pathology in 40 (48%) patients, whereas cerebral imaging revealed new findings in 45 (54%) patients. Previously unsuspected vascular findings were evident in 46 (55%) patients. Using the information from the MRIs, in 54 (64%) of patients mid-term follow-up was required, whereas in 7 (8%) patients a change of therapy or immediate treatment was necessary. CONCLUSION: Whole-body cardiovascular MRI is able to detect symptomatic and unsuspected findings in patients with PAOD. This technique was able to detect several vascular abnormalities that necessitated immediate medical attention and intervention in patients already identified as high-risk patients and, therefore, may show an increasing impact to determine individual therapeutic and follow-up concepts.