Background-Inflammation in adipose tissue has been implicated in vascular dysfunction, but the local mechanisms by which this occurs are unknown. Methods and Results-Small arteries with and without perivascular adipose tissue were taken from subcutaneous gluteal fat biopsy samples and studied with wire myography and immunohistochemistry. We established that healthy adipose tissue around human small arteries secretes factors that influence vasodilation by increasing nitric oxide bioavailability. However, in perivascular fat from obese subjects with metabolic syndrome (waist circumference 111Ϯ2.8 versus 91.1Ϯ3.5 cm in control subjects, PϽ0.001; insulin sensitivity 41Ϯ5.9% versus 121Ϯ18.6% in control subjects, PϽ0.001), the loss of this dilator effect was accompanied by an increase in adipocyte area (1786Ϯ346 versus 673Ϯ60 m 2 , PϽ0.01) and immunohistochemical evidence of inflammation (tumor necrosis factor receptor 1 12.4Ϯ1.1% versus 6.7Ϯ1%, PϽ0.001). Application of the cytokines tumor necrosis factor receptor-␣ and interleukin-6 to perivascular fat around healthy blood vessels reduced dilator activity, resulting in the obese phenotype. These effects could be reversed with free radical scavengers or cytokine antagonists. Similarly, induction of hypoxia stimulated inflammation and resulted in loss of anticontractile capacity, which could be rescued by catalase and superoxide dismutase or cytokine antagonists. Incubation with a soluble fragment of adiponectin type 1 receptor or inhibition of nitric oxide synthase blocked the vasodilator effect of healthy perivascular adipose tissue. Conclusions-We conclude that adipocytes secrete adiponectin and provide the first functional evidence that it is a physiological modulator of local vascular tone by increasing nitric oxide bioavailability. This capacity is lost in obesity by the development of adipocyte hypertrophy, leading to hypoxia, inflammation, and oxidative stress. Key Words: hypoxia Ⅲ inflammation Ⅲ obesity Ⅲ microcirculation Ⅲ nitric oxide synthase M etabolic syndrome is a precursor to type 2 diabetes mellitus and cardiovascular disease, with a prevalence of almost 40% in the adult population. 1 Central obesity is believed to be the main cause of metabolic syndrome, and this is reflected in newer definitions of the condition with large waist circumference as a prerequisite. 2 Although associations of obesity with hypertension, 3 insulin resistance, 4 and cardiovascular disease 5 are well described, the underlying mechanisms are poorly understood. Two areas of research that may provide insight into these are the vasoactive properties of perivascular adipose tissue (PVAT) and the inflammatory changes that occur in fat as obesity develops. Demonstrated in 1991, 6 it is now accepted that healthy PVAT has an anticontractile effect. [7][8][9][10] The mechanism appears to be both endothelium dependent via release of nitric oxide 8,10 and endothelium-independent via generation of hydrogen peroxide. 8 In obesity and metabolic syndrome, there is also a conformational chang...

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S. Roberts is supported by the NIHR Manchester Biomedical Research Centre.

These observations indicate that AMH is similarly related to insulin resistance and androgens in women with and without PCOS. This effect appears to be independent of age although an indirect causal effect due to ageing or some other mechanism cannot be ruled out. Excessive granulosa cell activity may be implicated in the abnormal follicular dynamic of the syndrome.

BackgroundIn a prospective observational study, we investigated whether patients with active systemic lupus erythematosus (SLE) had higher indices of endothelial damage and dysfunction than healthy controls and whether improved disease control was associated with improvement in these indices.MethodsTwenty-seven patients with active SLE (four or more American College of Rheumatology (ACR) criteria) and 22 age-matched controls were assessed. Endothelial microparticles (EMPs; CD31+/annexin V+/CD42b−) were quantified using flow cytometry. Brachial artery flow-mediated dilatation (FMD) was measured using automated edge-tracking software. Twenty-two patients had a second assessment at a median (IQR) of 20 (16, 22) weeks after initiating new immunosuppressive therapy.ResultsSLE patients had a median (IQR) baseline global British Isles Lupus Assessment Group Disease Activity Index (BILAG-2004) score of 14 (12, 22). CD31+/annexin V+/CD42b− EMPs were higher (157 548/ml (59 906, 272 643) vs 41 025(30 179, 98 082); p=0.003) and endothelial-dependent FMD was lower (1.63% (−1.22, 5.32) vs 5.40% (3.02, 8.57); p=0.05) in SLE patients than controls. CD31+/annexin V+/CD42b− EMPs correlated inversely with FMD (%) (r2 −0.40; p=0.006). At follow-up, the median (IQR) change in global BILAG-2004 score was −11 (−18, −3). CD31+/annexin V+/CD42b− EMP levels were reduced (166 982/ml (59 906, 278 775 vs 55 655(29 475, 188 659; p=0.02) and FMD had improved (0.33% (−2.31, 4.1) vs 3.19% (0.98, 5.09); p=0.1) at the second visit.ConclusionsActive SLE is associated with evidence of increased endothelial damage and endothelial dysfunction, which improved with suppression of inflammation. Better control of active inflammatory disease may contribute to improved cardiovascular risk in patients with SLE.

AMH may exhibit assay-specific preanalytical instability. Robust protocols for the development and validation of commercial AMH assays are required.

OBJECTIVERisks of diabetes and cardiovascular disease are elevated worldwide in Indian Asians. However, risks of other diabetes-related complications, i.e., foot ulceration and amputation, also with a vascular basis, are substantially lower in Asians than in white Europeans in the U.K., possibly due to less neuropathy. We therefore compared signs, symptoms, and objective quantitative measures of diabetic neuropathy and their risk factors in Indian Asians and Europeans.RESEARCH DESIGN AND METHODSThis was a cross-sectional study of a population-based sample of age- and sex-matched adults with type 2 diabetes of European (95 male and 85 female) and Asian (96 male and 84 female) descent in the U.K. Patients were assessed for neuropathic symptoms, signs, nerve conduction, autonomic function, and quantitative sensory testing. Peripheral vascular function and other potential risk factors for neuropathy were measured.RESULTSMean nerve conduction velocity Z scores were better in Asians (mean ± SD 0.07 ± 0.62) than in Europeans (−0.11 ± 0.60; P = 0.007) and were explained by the shorter height, fewer pack-years smoked, and higher transcutaneous oxygen levels (TCpO2) in Indian Asians (P value for ethnic comparison attenuated to 0.2). Small fiber neuropathy was less prevalent in Indian Asians compared with Europeans (odds ratio 0.58 [95% CI 0.37–0.93]; P = 0.02) and was primarily accounted for by better TCpO2 (0.70 [0.40–1.21]; P = 0.2).CONCLUSIONSAsians with diabetes have substantially less large and small fiber neuropathy than Europeans, despite comparable traditional risk factors. Independent from smoking, the lower risk of neuropathy in Asians is due to better skin microvascularization and may help explain the substantially reduced Asian foot ulcer risk.

Although large, prospective, multicentre studies are indicated, we have clearly demonstrated that individualized, AMH-guided, controlled ovarian hyperstimulation protocols significantly improved positive clinical outcomes, reduced the incidence of complications and reduced the financial burden associated with assisted reproduction.