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The inflammatory phenotype of neck adipose tissue (NAT) might reflect its involvement in the pathogenesis of carotid atherosclerosis. We investigated inflammatory gene expression in the subcutaneous and the perivascular (pericarotid) adipose tissue from patients with carotid stenosis (CS) undergoing endarterectomy and a control group of patients without significant carotid atherosclerosis undergoing thyroid surgery. Only male patients were included (n = 13 in each study group). Clinical and biochemical data along with serum leptin, adiponectin, and monocyte chemoattractant protein 1 (MCP-1) were collected. Adipose tissue samples were obtained from both the subcutaneous and pericarotid compartments. Real-time polymerase chain reaction was used to measure gene expression of macrophage markers and adipokines. The CS group had higher subcutaneous and pericarotid visfatin gene expression and higher pericarotid expression of MCP-1 and CD68 genes. The ratio between pericarotid CD206 and CD68 gene expression was similar between study groups. Adiponectin gene expression in both NAT compartments did not differ between groups, but it was negatively associated with body weight. These observations suggest that NAT, and especially the pericarotid compartment, express enhanced inflammatory properties in patients with CS, but the proportion of anti-inflammatory macrophages in advanced atherosclerosis seems to be maintained.

Introduction: Post heart transplantation (HTx) infective endocarditis (IE) is unique among endocarditis after solid organ transplantation because it is the transplanted organ that becomes infected. Since 2016 two HTx patients have been successfully treated in University Hospital Dubrava for cardiac allograft infective endocarditis. Case report: The first one, a 77-year-old male patient, who in 2001 underwent orthotopic HTx due to ischemic cardiomyopathy, and who since 2010 was on hemodialysis due to chronic terminal kidney failure, was admitted in June 2016 due to mitral valve endocarditis (Figure 1). The other one was a 29-year-old male patient who in January 2016 had undergone orthotopic heart transplantation due to dilated cardiomyopathy and was diagnosed in June 2017 with tricuspid valve endocarditis (Figure 2). Both patients had atypical presentation, and in both patients transthoracic and transesophageal echocardiography were immediately performed revealing valve vegetations and proving crucial for establishing diagnosis. Empirical antibiotic treatment was initiated at once, and the patients were referred to the endocarditis team. Conclusion: IE is a known, but rare and very often fatal complication of HTx. Frequent central venous catheter access and multiple endomyocardial biopsies appear to predispose to infection1. The prognosis of post-HTx IE remains poor. Atypical presentation is common in these patients2, and therefore a high index of suspicion and low threshold for investigation are appropriate in this group in order to avoid delays in diagnosis3. There are no specific guidelines to diagnostic practice for this particular group, however, echocardiography is the mainstay and essential in diagnosis of endocarditis4, and therefore has to be performed at the earliest possible time.

Upper body adipose tissue accumulation has been associated with clustering of metabolic disorders and increased cardiovascular risk. Neck circumference (NC) indicated that subcutaneous adipose tissue (SAT) in that region is an independent pathogenic depot that might account for the additional risk missed by visceral adipose tissue (VAT). Neck adipose tissue (NAT) is not only one more ectopic depot but has several particular features that might modulate its metabolic role. Besides a controversial impact on obstructive apnea syndrome, neck fat encompasses carotid arteries as an important perivascular adipose tissue (PVAT) depot. With dysfunctional changes in obesity, physiologic vascular regulation is lost and inflammatory signals accelerate atherogenesis. Unexpected was the discovery of brown and beige adipocytes in the neck of human adults. When stimulated, brown adipose tissue (BAT) dissipates energy through thermogenesis and it is associated with other favorable metabolic effects. Moreover, the neck is the region where the browning mechanism was disclosed. With this unique plastic nature, NAT revealed multiple ties, challenging dynamics and potential new therapeutic targets that might have significant implications on metabolic outcomes and vascular risk.

Retinol-binding protein 4 (RBP4) is considered as an important mediator of insulin resistance and metabolic syndrome (MS). In adipose tissue (AT)) it is mainly secreted from visceral depots. The residual metabolic risk which remains beyond that caused by visceral AT seems to be hold by upper body subcutaneous AT. This large pathogenic depot might be representative by subcutaneous neck AT. The aim of this study was to examine and to compare RBP4 gene expressions in paired superficial and deep subcutaneous neck AT. We also investigated their associations with metabolic risk factors and serum RBP4. Samples of both superficial and deep neck subcutaneous AT were taken in 38 patients during routine neck surgery. RBP4 gene expression was analysed by RQ-PCR method. Serum was taken preoperatively to determine insulin, glucose, triglycerides, HDL-cholesterol, C-reactive protein and RBP4. Anthropometric measurements and bioelectric impedance analysis were also performed. Study participants were divided in two groups - with and without MS according to revised NCEP ATP III criteria. RBP4 gene expressions in AT and serum level were not different between our study groups. RBP4 gene expressions were significantly lower in superficial than in deep AT in the group without MS. In patients with MS different RBP4 gene expressions between layers of AT were not present. In the whole sample of participants superficial RBP4 gene expression positively correlated with fat mass, insulin and HOMA index. Serum RBP4 did not correlate with RBP4 gene expressions, but it correlated with waist circumference, insulin, HOMA index and triglycerides. Our results indicate that superficial and deep neck subcutaneous AT might have a different secretory profile. Superficial layers with metabolically more favourable aspects are absent in subjects with MS suggesting that dysfunctional changes occur in all layers of upper body subcutaneous AT and might contribute to insulin resistance.

Adipokines are an important contributor to the circulatory milieu of the body. The spectrum of adipokines changes as dysfunctional features of adipose tissue develop and the menopause is a time when an impairment of metabolic balance appears. The aim of this study was to examine several serum adipokines and adiponectin gene expression in subcutaneous and deep neck adipose tissue in women. Samples of serum, subcutaneous and deep neck adipose tissue were taken in 41 (12 premenopausal and 29 postmenopausal) women undergoing routine thyroid or vascular surgery. Serum adiponectin, leptin, omentin-1, monocyte chemoattractant protein-1 (MCP-1), fibroblast growth factor 21 (FGF21), retinol binding protein 4 (RBP4), insulin, glucose, triglycerides, HDL-cholesterol and C-reactive protein were determined. HOMA-IR was calculated and anthropometric measurements were performed. Adiponectin gene expression in adipose tissue samples was analysed by RQ–PCR method. Serum adiponectin and omentin-1 were negatively and leptin was positively associated with body weight, BMI and waist and neck circumference. RBP4 correlated with waist circumference and triglycerides. Leptin also was associated positively and omentin-1 negatively with triglycerides. FGF21 correlated with glucose and HDL-cholesterol. Omentin-1 negatively correlated with RBP4 and positively with serum adiponectin. Both serum adiponectin and omentin-1 were negatively associated with leptin. MCP-1 correlated only with RBP4. FGF21 didn’t correlate with other adipokines. Subcutaneous and deep adiponectin gene expressions were negatively associated with insulin, HOMA-IR and RBP4 but positively with omentin-1. Comparisons between premenopausal and postmenopausal group yielded significant differences in insulin, HOMA-IR, MCP-1 and RBP4. These results confirm multiple associations of various adipokines with metabolic parameters and secretory features of the neck adipose tissue depot. However, they also suggest that some adipokines cluster in specific profiles with potential particular biologic functions that should be further elucidated.

Adipose tissue is an endocrine organ that actively contributes to the development of the metabolic dysfunction but it is not homogenous and the nature of its impact considerably depends on its anatomic location. So far both subcutaneous and deep neck adipose tissue depots were individually related to increased metabolic risk but their particular features were not mutually compared. Adiponectin is an adipocytokine that has consistently showed higher mRNA expression in subcutaneous than in deep or visceral adipose tissue. The aim of this study was to examine adiponectin gene expression in subcutaneous and deep perivascular neck adipose tissue and their association with metabolic risk factors in patients undergoing neck surgery. Samples of both subcutaneous and deep adipose tissue along carotid artery were taken in 31 patients during routine thyroid or neck vascular surgery. We analysed adiponectin gene expression in these tissue samples by RQ-PCR method. Serum samples were taken preoperatively to determine insulin, glucose, triglycerides, HDL-cholesterol and C-reactive protein. Anthropometric measurements were also performed. Study participants did not have any inflammatory or malignant diseases. Adiponectin gene expression was significantly higher in subcutaneous than in deep neck adipose tissue (P

Adipose tissue distribution is one of the key determinants of metabolic dysfunction in obesity. Several large scale studies found that enlarged neck circumference is independently associated with cardiovascular risk. The aim of this study was to examine the association of neck circumference with metabolic risk factors in patients undergoing neck surgery. In 36 patients undergoing thyroid or vascular neck surgery we determined serum levels of insulin, glucose, triglycerides, HDL-cholesterol and C-reactive protein. We performed anthropometric measurements (body weight and height, BMI, waist circumference and neck circumference) and body composition analysis. We also evaluated carotid intima-media thickness and the presence of carotid plaques. Study participants did not have any inflammatory or malignant diseases. They also did not have any thyroid or other specific neck mass that could particularly enlarge neck circumference. Statistically significant positive correlations were found between neck circumference, other anthropometric measures of obesity and body fat mass (P