Vascular endothelial growth factor (VEGF) promotes angiogenesis, and elevated levels are found in plaques of psoriasis. Two VEGF polymorphisms, +405 and -460, are associated with early-onset psoriasis and are close to the functional activator protein-1 site (+419) through which retinoids, an established systemic therapy for psoriasis, can block production of VEGF. We report that peripheral blood mononuclear cells (PBMCs) and epidermal keratinocytes (KC) from patients with psoriasis demonstrate differential, genotype-dependent, regulation of VEGF. For PBMCs, VEGF genotype distinguishes two groups of patients with psoriasis - "high and low VEGF producers" (P < 0.001). In contrast, KC production of VEGF is not genotype dependent. However, the effects of all-trans retinoic acid (RA) on cellular expression of VEGF are determined by both cell type and genotype. RA inhibits KC production of VEGF in a genotype-dependent manner (P < 0.005) whereas RA stimulates PBMCs production irrespective of VEGF genotype (P < 0.001). We also report that the -460 VEGF polymorphism appears to have a clinical pharmacogenetic role in predicting response or non-response of psoriasis to acitretin (P = 0.01). In future, determination of VEGF gene polymorphisms and thus individual patient VEGF "signatures" may be used as a prognostic factor for psoriasis susceptibility/severity and as a means for optimizing treatment response.

Diabetic retinopathy and nephropathy cause significant morbidity in patients with diabetes. Vascular endothelial growth factor (VEGF) is a potent angiogenic and vascular permeability factor and is implicated in both of these diabetes complications. We previously reported transfection studies showing the VEGF ؊460 and VEGF ؉405 polymorphisms to increase basal VEGF promoter activity by 71% compared with the wild-type sequence. Therefore, we investigated the association of these VEGF polymorphisms with proliferative diabetic retinopathy and diabetic nephropathy. DNA was isolated from 267 U.K. Caucasians with diabetes, comprising 69 patients with proliferative retinopathy and 198 patients with other grades of retinopathy. The distribution of VEGF ؊460 genotype was significantly different between the proliferative retinopathy and nonproliferative retinopathy groups (P ‫؍‬ 0.027); specifically, carriage of the VEGF ؊460C allele was associated with proliferative diabetic retinopathy (odds ratio 2.5 [95% CI 1.20 -5.23]). The VEGF ؊460 genotype was predictive of retinopathy, even after controlling for blood pressure, glycemic control, duration of diabetes, and obesity (P ‫؍‬ 0.02). The VEGF ؉405 genotype did not associate with proliferative retinopathy, and neither polymorphism was associated with diabetic nephropathy. The VEGF ؊460C polymorphism is a positive independent predictive factor for the development of proliferative diabetic retinopathy. Increased VEGF production from high-expressing haplotypes, including ؊460C, may promote neovascularization. Diabetes 53: [861][862][863][864] 2004

BackgroundExtended criteria donor (ECD) and donation after circulatory death (DCD) kidneys are at increased risk of delayed graft function (DGF). Experimental evidence suggests that erythropoietin (EPO) attenuates renal damage in acute kidney injury. This study piloted the administration of high dose recombinant human EPO-beta at implantation of ECD and DCD kidneys, and evaluated biomarkers of kidney injury post-transplant.MethodsForty patients were randomly assigned to receive either rhEPO-b (100,000 iu) (n = 19 in the intervention group, as 1 patient was un-transplantable post randomisation), or placebo (n = 20) in this, double blind, placebo-controlled trial at Manchester Royal Infirmary from August 2007 to June 2009. Participants received either an ECD (n = 17) or DCD (n = 22) kidney. Adverse events, renal function, haematopoietic markers, and rejections were recorded out to 90 days post-transplant. Biomarkers of kidney injury (neutrophil gelatinase-associated lipocalin, Kidney Injury Molecule-1 and IL-18) were measured in blood and urine during the first post-operative week.ResultsThe incidence of DGF (53% vs 55%) (RR = 1.0; CI = 0.5-1.6; p = 0.93) and slow graft function (SGF) (32% vs 25%) (RR = 1.1; CI = 0.5-1.9; p = 0.73) respectively, serum creatinine, eGFR, haemoglobin and haematocrit, blood pressure, and acute rejection were similar in the 2 study arms. High dose rhEPO-b had little effect on the temporal profiles of the biomarkers.ConclusionsHigh dose rhEPO-b appears to be safe and well tolerated in the early post- transplant period in this study, but has little effect on delayed or slow graft function in recipients of kidneys from DCD and ECD donors. Comparing the profiles of biomarkers of kidney injury (NGAL, IL-18 and KIM-1) showed little difference between the rhEPO-b treated and placebo groups. A meta-analysis of five trials yielded an overall estimate of the RR for DGF of 0.89 (CI = 0.73; 1.07), a modest effect favouring EPO but not a significant difference. A definitive trial based on this estimate would require 1000-2500 patients per arm for populations with base DGF rates of 50-30% and 90% power. Such a trial is clearly unfeasible.Trial registrationEudraCT Number 2006-005373-22 ISRCTN ISRCTN85447324 registered 19/08/09.

BackgroundPatients with chronic kidney disease (CKD) need regular monitoring, usually by blood urea and creatinine measurements, needing venepuncture, frequent attendances and a healthcare professional, with significant inconvenience. Noninvasive monitoring will potentially simplify and improve monitoring. We tested the potential of transdermal reverse iontophoresis of urea in patients with CKD and healthy controls.MethodsUsing a MIC 2® Iontophoresis Controller, reverse iontophoresis was applied on the forearm of five healthy subjects (controls) and 18 patients with CKD for 3–5 h. Urea extracted at the cathode was measured and compared with plasma urea.ResultsReverse iontophoresis at 250 μA was entirely safe for the duration. Cathodal buffer urea linearly correlated with plasma urea after 2 h (r = 0·82, P < 0·0001), to 3·5 h current application (r = 0·89, P = 0·007). The linear equations y = 0·24x + 1 and y = 0·21x + 4·63 predicted plasma urea (y) from cathodal urea after 2 and 3 h, respectively. Cathodal urea concentration in controls was significantly lower than in patients with CKD after a minimum current application of 2 h (P < 0·0001), with the separation between the two groups becoming more apparent with longer application (P = 0·003). A cathodal urea cut-off of 30 μM gave a sensitivity of 83·3% and positive predictive value of 87% CKD. During haemodialysis, the fall in cathodal urea was able to track that of blood urea.ConclusionReverse iontophoresis is safe, can potentially discriminate patients with CKD and healthy subjects and is able to track blood urea changes on dialysis. Further development of the technology for routine use can lead to an exciting opportunity for its use in diagnostics and monitoring.

Introduction: Neutrophil gelatinase-associated lipocalin (NGAL), interleukin-18 (IL-18) and kidney injury molecule-1 (KIM-1) have been suggested to be predictive of delayed graft function (DGF) following kidney transplantation. Studies to date have examined urine biomarker levels beginning post-operatively, without consideration for the contribution of residual renal function from the native kidneys. We performed a prospective study in recipients of ECD and NHBD kidneys, which examined the natural history of urine NGAL, IL-18 and KIM-1 levels from pre-engraftment until day 5 post-transplantation. Methods: In total, 39 patients were recruited into the study. Urine samples were collected longitudinally from the recipients preoperatively until day 5 post-transplantation. 21 out of the 39 recruited patients provided a native urine sample. NGAL, IL-18 and KIM-1 levels were measured by immunoassay and corrected for urine creatinine levels. All values relate to native urine biomarker levels in recipients prior to engraftment. Results: Urine NGAL (uNGAL) levels ranged from 0 -10367ng/mgCr and were inversely correlated with native urine output (Spearman r = -0.66, p=0.001). Urine KIM-1 (uKIM-1) levels ranged from 0 -9980pg/mgCr and were also inversely correlated with native urine output (Spearman r = -0.46, p=0.048). Urine IL-18 (uIL-18) levels were not correlated with urine output and ranged from 0 -2630pg/mgCr. Haemodialysis patients had higher uNGAL compared to peritoneal dialysis or pre-dialysis patients (ANOVA, p=0.004). uIL-18 and uKIM-1 levels did not correlate with dialysis modality. DGF, defined as the need for haemodialysis in the first week post transplantation, occurred in 9/21 patients and did not correlate with native uIL-18 or uKIM-1 levels. High uNGAL levels were present in native urine from patients who subsequently developed DGF (Mann Whitney, p=0.02). Finally, native biomarker levels of uNGAL and uKIM-1 were the strongest predictors of their posttransplant levels out to day 5, in a mixed effects model containing NGAL, IL-18, KIM-1 and donor type (p<0.004). Conclusions: The results from this study demonstrate that high levels of the biomarkers NGAL, IL-18 and KIM-1 can be found in native urine in the preoperative period. These levels were the strongest predictor of post-transplant levels, at all time points in the early post transplant period, irrespective of donor type. Thus native urine biomarker levels may confound early post operative measurements, which need to be viewed with caution when used in the prediction of AKI and DGF.