M. C. van den Heuvel

Tubular kidney injury molecule-1 (KIM-1) in human renal disease.

KIM‐1, a transmembrane tubular protein with unknown function, is undetectable in normal kidneys, but is markedly induced in experimental renal injury. The KIM‐1 ectodomain is cleaved, detectable in urine, and reflects renal damage. KIM‐1 expression in human renal biopsies and its correlation with urinary KIM‐1 (uKIM‐1) is unknown. In biopsies from various renal diseases (n = 102) and controls (n = 7), the fraction of KIM‐1 positive tubules and different renal damage parameters were scored. Double labelling was performed for KIM‐1 with macrophages (MØ), α‐smooth muscle actin (α‐SMA), proximal (aquaporin‐1) and distal (E‐cadherin) tubular markers and a dedifferentiation marker (vimentin). uKIM‐1 at the time of biopsy (n = 53) was measured by ELISA. Renal KIM‐1 was significantly increased in all diseases versus controls (p < 0.05), except minimal change. KIM‐1 was primarily expressed at the luminal side of dedifferentiated proximal tubules, in areas with fibrosis (α‐SMA) and inflammation (MØ). Independent of the disease, renal KIM‐1 correlated positively with renal damage, negatively with renal function, but not with proteinuria. uKIM‐1 was increased in renal patients versus controls (p < 0.001), including minimal change, and correlated positively with tissue KIM‐1 and MØ, negatively with renal function, but not with proteinuria. In conclusion, KIM‐1 is upregulated in renal disease and is associated with renal fibrosis and inflammation. uKIM‐1 is also associated with inflammation and renal function, and reflects tissue KIM‐1, indicating that it can be used as a non‐invasive biomarker in renal disease. Copyright

ADAM17 upregulation in human renal disease: a role in modulating TGF-alpha availability?

A disintegrin and metalloproteinase (ADAM)17 sheds growth factors from the cell membrane, including epidermal growth factor receptor (EGFR) ligand transforming growth factor (TGF)-alpha. In mice, angiotensin II infusion induces renal fibrosis via ADAM17-mediated TGF-alpha shedding and subsequent EGFR activation. Pharmacological ADAM17 inhibition reduced renal fibrotic lesions and improved renal function, positioning ADAM17 as a promising target of intervention in renal disease. We studied ADAM17 expression in the human kidney. ADAM17 mRNA was constitutively expressed in normal adult kidneys, with highest expression in distal tubules. In human renal disease, ADAM17 was de novo expressed in proximal tubules, peritubular capillaries, and glomerular mesangium and upregulated in podocytes. Glomerular mesangial and endothelial ADAM17 were associated with mesangial matrix expansion, focal glomerulosclerosis, and glomerular macrophage infiltration (P < 0.01). Peritubular capillary and proximal tubular ADAM17 were associated with interstitial fibrosis and interstitial macrophage infiltration (P < 0.05). Both glomerular and interstitial ADAM17 were associated with decreased renal function (P < 0.05). In renal fibrosis, ADAM17 colocalized with TGF-alpha. Moreover, in cultured human podocytes and proximal tubular cells, pharmacological ADAM17 inhibition reduced constitutive TGF-alpha shedding by 78% (P < 0.005) and 100% (P < 0.05), respectively, and phorbol ester-induced TGF-alpha shedding by 84% (P < 0.005) and 92% (P = 0.005), respectively. Finally, ADAM17 inhibition reduced cellular proliferation. In conclusion, the ADAM17 expression pattern and its role in shedding TGF-alpha from cultured human kidney cells suggest a role in the development of fibrosis. Since EGFR signaling is implicated in renal fibrosis, targeting ADAM17 to reduce availability of EGFR ligand TGF-alpha may represent a promising way of intervention in human renal disease.

Glomerular and tubular induction of the transcription factor c-Jun in human renal disease.

The transcription factor c‐Jun regulates the expression of genes involved in proliferation and inflammation in many cell types but its role in human renal disease is largely unclear. In the current study we investigated whether c‐Jun activation is associated with human renal disease and if c‐Jun activation regulates pro‐inflammatory and pro‐fibrotic genes in renal cells. Activation of c‐Jun was quantified by scoring renal expression of phosphorylated c‐Jun (pc‐Jun) in control human renal tissue and in biopsies from patients with various renal diseases (diabetic nephropathy, focal glomerulosclerosis, hypertension, IgA nephropathy, membranous glomerulopathy, minimal change disease, membranoproliferative glomerulonephritis, systemic lupus erythematosus, acute rejection, and Wegeners granulomatosis); this was correlated with parameters of renal damage. Furthermore, we studied the functional role of c‐Jun activation in human tubular epithelial cells (HK‐2) stimulated with TGF‐β. Activated c‐Jun was present in nuclei of glomerular and tubular cells in all human renal diseases, but only sporadically in controls. Across the diseases, the extent of pc‐Jun expression correlated with the degree of focal glomerulosclerosis, interstitial fibrosis, cell proliferation, kidney injury molecule‐1 (Kim‐1) expression, macrophage accumulation, and impairment of renal function. In HK‐2 cells, TGF‐β induced c‐Jun activation after 1 h (+40%, p < 0.001) and 24 h (+160%, p < 0.001). The specific c‐Jun N‐terminal kinase (JNK) inhibitor SP600125 abolished c‐Jun phosphorylation at all time points and blunted TGF‐β‐ or BSA‐induced procollagen‐1α 1 and MCP‐1 gene expression in HK‐2 cells. We conclude that in human renal disease, the transcription factor c‐Jun is activated in glomerular and tubular cells. Activation of c‐Jun may be involved in the regulation of inflammation and/or fibrosis in human renal disease. Copyright

The significance of parenchymal changes of acute cellular rejection in predicting chronic liver graft rejection

Background. Chronic rejection (CR) in liver allografts shows a rapid onset and progressive course, leading to graft failure within the first year after transplantation. Most cases are preceded by episodes of acute cellular rejection (AR), but histological features predictive for the transition toward CR are not well documented. Methods. We assessed the predictive value of centrilobular necrosis, central vein endothelialitis (CVE), central vein fibrosis, and lobular inflammation in the development of CR. One-week and one-month biopsy specimens of 12 patients with CR were compared with those of a control group consisting of 17 patients, who experienced AR without developing CR. The progress of the histological changes was further evaluated in follow-up biopsy specimens of the CR group taken at 2 months and beyond 3 months after transplantation. Results. Centrilobular necrosis, CVE, central vein fibrosis, and lobular inflammation were common features in both groups at 1 week. At 1 month, the incidence declined in the control group. The CR group showed an increased incidence and persistence of these features in the follow-up biopsy specimens. The incidence and median grade of severity of CVE was significantly higher in the CR group (P =0.04 and P <0.001). The severity of portal and lobular inflammation was also more pronounced in the CR group (P =0.01 and 0.068). Conversely, in the control group, the incidence of the lobular features decreased and the severity of CVE declined significantly (P =0.03). Conclusion. The shift from a predominantly portal-based process toward lobular graft damage represents the early transition of AR to CR, for which a modification of immunosuppression might be necessary to prevent graft loss.

Repeat dosing of rocuronium 1.2 mg kg−1 after reversal of neuromuscular block by sugammadex 4.0 mg kg−1 in anaesthetized healthy volunteers: a modelling-based pilot study

BACKGROUND Re-intubation and re-operation may occasionally be required after neuromuscular block (NMB) reversal. This study evaluated block onset times of a second dose of rocuronium (1.2 mg kg(-1)) after sugammadex reversal of rocuronium 0.6 mg kg(-1). METHODS In this open-label study of healthy anaesthetized volunteers, subjects received rocuronium 0.6 mg kg(-1), were antagonized at 1-2 post-tetanic counts with sugammadex 4.0 mg kg(-1), and received rocuronium 1.2 mg kg(-1) at 5, 7.5, 10, 15, 20, 22.5, 25, 27.5, 30, 45, or 60 min after sugammadex. Spontaneous recovery occurred after repeat rocuronium dose. Primary endpoints were the onset time of maximal block (time to lowest T(1) value reached) and the clinical duration of block (until T(1)=25%) after repeat rocuronium dose. RESULTS Sixteen subjects were included. For subjects receiving rocuronium 1.2 mg kg(-1) 5 min after sugammadex (n=6), mean (sd) onset time (to T(1)=0) was 3.06 (0.97) min; range, 1.92-4.72 min. For repeat dose time points ≥25 min (n=5), mean onset was faster (1.73 min) than for repeat doses <25 min (3.09 min) after sugammadex. The duration of block ranged from 17.7 min (rocuronium 5 min after sugammadex) to 46 min (repeat dose at 45 min). Mean duration was 24.8 min for repeat dosing <25 min vs 38.2 min for repeat doses ≥25 min. CONCLUSIONS Rapid re-onset of NMB occurred after repeat dose of rocuronium 1.2 mg kg(-1) as early as 5 min after sugammadex in healthy volunteers. Re-onset of block took longer if second rocuronium dose was <25 min after sugammadex. The duration of action of second rocuronium dose increased with later repeat dose time points.

Optically active 6-acetyloxy-2H-pyran-3(6H)-one obtained by lipase catalyzed transesterification and esterification

Abstract Kinetic resolution of 6-acetyloxy-2 H -pyran-3(6 H )-one ( 1 ) is achieved by immobilized lipase PS on Hyflo Super Cell in organic solvents. Transesterification in hexane/n-butanol yields enantiomerically pure R -(−)-6-acetyloxy-2 H -pyran-3(6 H )-one, whereas esterification of 6-hydroxy-2 H -pyran-3(6 H )-one ( 2 ) with vinyl acetate by immobilized lipase PS gives the S -enantiomer with e.e.s up to 76%.

Dialysability of sugammadex and its complex with rocuronium in intensive care patients with severe renal impairment

BACKGROUND Renal excretion is the primary route for the elimination of sugammadex. We evaluated the dialysability of sugammadex and the sugammadex-rocuronium complex in patients with severe renal impairment in the intensive care unit (ICU). METHODS Six patients in the ICU with acute severe renal impairment received general anaesthesia for transoesophageal echocardiography, to replace their tracheal tubes, or for bronchoscopy. Five of the six patients were in the ICU after cardiac/vascular surgery and one for pneumonia-induced respiratory failure. They all received rocuronium 0.6 mg kg(-1), followed 15 min later by sugammadex 4.0 mg kg(-1). Two patients were studied for two dialysis episodes and four patients for four episodes. Rocuronium and sugammadex concentrations were measured in plasma and dialysate at several time points before, during, and after high-flux dialysis. Dialysis clearance in plasma and dialysate, and reduction ratio (RR) (the extent of the plasma concentration reduction at the end of a dialysis episode when compared with before dialysis) were calculated for each dialysis episode. RESULTS Dialysis episodes lasted on average 6 h. Observed RRs indicated mean reductions of 69% and 75% in the plasma concentrations of sugammadex and rocuronium, respectively, during the first dialysis episode. Reductions were around 50% during sequential dialysis episodes. On average, dialysis clearance of sugammadex and rocuronium in blood was 78 and 89 ml min(-1), respectively. CONCLUSIONS Haemodialysis using a high-flux dialysis method is effective in removing sugammadex and the sugammadex-rocuronium complex in patients with severe renal impairment.

Systemic lupus erythematosus and Wiskott-Aldrich syndrome in an Italian patient

Systemic lupus erythematosus has not yet been associated with mutations in the Wiskott-Aldrich syndrome gene; moreover, the time courses of platelet number and size in patients with Wiskott-Aldrich syndrome are unknown. In this case, we present the time trends of platelet count and volume and the histopathology of the kidney of a patient with systemic lupus erythematosus and a mutation in the Wiskott-Aldrich syndrome gene. The patient suffered from congenital recessive X-linked thrombocytopenia, and he developed systemic lupus erythematosus at the age of 12 years. Thus, his disease was reclassified as Wiskott-Aldrich syndrome, class 5. The g.257G > A mutation in the Wiskott-Aldrich syndrome gene and reduced expression of the specific messenger were revealed by molecular analyses.

Propofol-based anaesthesia versus sevoflurane-based anaesthesia for living donor kidney transplantation: results of the VAPOR-1 randomized controlled trial

Background. Kidney transplantation is associated with harmful processes affecting the viability of the graft. One of these processes is associated with the phenomenon of ischaemia‐reperfusion injury. Anaesthetic conditioning is a widely described strategy to attenuate ischaemia‐reperfusion injury. We therefore conducted the Volatile Anaesthetic Protection of Renal Transplants‐1 trial, a pilot project evaluating the influence of two anaesthetic regimens, propofol‐ vs sevoflurane‐based anaesthesia, on biochemical and clinical outcomes in living donor kidney transplantation. Methods. Sixty couples were randomly assigned to the following three groups: PROP (donor and recipient propofol), SEVO (donor and recipient sevoflurane), and PROSE (donor propofol and recipient sevoflurane). The primary outcome was renal injury reflected by urinary biomarkers. The follow‐up period was 2 yr. Results. Three couples were excluded, leaving 57 couples for analysis. Concentrations of kidney injury molecule‐1 (KIM‐1), N‐acetyl‐&bgr;‐D‐glucosaminidase (NAG), and heart‐type fatty acid binding protein (H‐FABP) in the first urine upon reperfusion showed no differences. On day 2, KIM‐1 concentrations were higher in SEVO [952.8 (interquartile range 311.8‐1893.0) pg mmol‐1] compared with PROP [301.2 (202.0‐504.7) pg mmol‐1]. This was the same for NAG: SEVO, 1.835 (1.162‐2.457) IU mmol‐1vs PROP, 1.078 (0.819‐1.713) IU mmol‐1. Concentrations of H‐FABP showed no differences. Measured glomerular filtration rate at 3, 6, and 12 months showed no difference. After 2 yr, there was a difference in the acute rejection rate (P=0.039). Post hoc testing revealed a difference between PROP (35%) and PROSE (5%; P=0.020). The difference between PROP and SEVO (11%) was not significant (P=0.110). Conclusions. The SEVO group showed higher urinary KIM‐1 and NAG concentrations in living donor kidney transplantation on the second day after transplantation. This was not reflected in inferior graft outcome. Clinical trial registration. NCT01248871.