To cite this article: Lattenist L, Ochodnick y P, Ahdi M, Claessen N, Leemans JC, Satchell SC, Florquin S, Gerdes VE, Roelofs JJTH. Renal endothelial protein C receptor expression and shedding during diabetic nephropathy. J Thromb Haemost 2016; 14: 1171-82. EssentialsEndothelial protein C receptor (EPCR) promotes diabetic nephropathy (DN) outcome improvement. Renal expression and shedding of EPCR were measured in diabetic patients with or without DN. Inhibition of metalloproteinase-driven EPCR shedding restored glomerular endothelium phenotype. EPCR shedding through metalloproteinase ADAM17 contributes to the worsening of DN.Summary. Background: Diabetic nephropathy (DN) represents the leading cause of end-stage renal disease. The endothelial protein C receptor (EPCR) and its ligand (activated protein C) have been shown to ameliorate the phenotype of DN in mice. EPCR activity can be regulated by proteolytic cleavage involving ADAMs, yielding a soluble form of EPCR (sEPCR). Objective: To characterize the renal expression and shedding of EPCR during DN. Methods: EPCR levels were measured in plasma, urine and biopsy samples of diabetic patients with (n = 73) or without (n = 63) DN. ADAM-induced cleavage of EPCR was investigated in vitro with a human glomerular endothelium cell line. Results: DN patients showed higher plasma and urinary levels of sEPCR than diabetic controls (112.2 versus 135.2 ng mL À1 and 94.35 versus 140.6 ng mL À1

Skin AF measurement is a valuable tool for the assessment of micro- and macrovascular complication risk in patients with light skin color types. Even after exclusion of patients with too low a reflectance, the current performance of the AGE Reader™ (DiagnOptics Technologies BV, Groningen, The Netherlands) was insufficient in darker-skinned patients.

Background Diabetic nephropathy (DN) is a major complication of diabetes and the main cause of end-stage renal disease. Extracellular vesicles (EVs) are small cell-derived vesicles that can alter disease progression by microRNA (miRNA) transfer. Methods In this study, we aimed to characterize the cellular origin and miRNA content of EVs in plasma samples of type 2 diabetes patients at various stages of DN. Type 2 diabetes patients were classified in three groups: normoalbuminuria, microalbuminuria and macroalbuminuria. The concentration and cellular origin of plasma EVs were measured by flow cytometry. A total of 752 EV miRNAs were profiled in 18 subjects and differentially expressed miRNAs were validated. Results Diabetic patients with microalbuminuria and/or macroalbuminuria showed elevated concentrations of total EVs and EVs from endothelial cells, platelets, leucocytes and erythrocytes compared with diabetic controls. miR-99a-5p was upregulated in macroalbuminuric patients compared with normoalbuminuric and microalbuminuric patients. Transfection of miR-99a-5p in cultured human podocytes downregulated mammalian target of rapamycin (mTOR) protein expression and downregulated the podocyte injury marker vimentin. Conclusions Type 2 diabetes patients with microalbuminuria and macroalbuminuria display differential EV profiles. miR-99a-5p expression is elevated in EVs from macroalbuminuria and mTOR is its validated mRNA target.

TAM receptors (Tyro3, Axl, and Mer) have been implicated in innate immunity. Circulating TAM receptor soluble forms (sTyro3, sAxl, sMer) are related to autoimmune disorders. We investigated TAM and their ligand protein S in patients with diabetes. Urinary and plasma levels of protein S, sTyro3, sAxl, and sMer were determined in 126 patients with diabetes assigned to a normoalbuminuric or macroalbuminuric (urinary albumin excretion <30 mg/24 hours and >300 mg/24 hours, respectively) study group and 18 healthy volunteers. TAM and protein S immunostaining was performed on kidney biopsy specimens from patients with diabetic nephropathy (n = 9) and controls (n = 6). TAM expression and shedding by tubular epithelial cells were investigated by PCR and enzyme-linked immunosorbent assay in an in vitro diabetes model. Patients with macroalbuminuria diabetes had higher circulating levels of sMer and more urinary sTyro3 and sMer than normoalbuminuric diabetics. Increased clearance of sTyro3 and sMer was associated with loss of tubular Tyro3 and Mer expression in diabetic nephropathy tissue and glomerular depositions of protein S. During in vitro diabetes, human kidney cells had down-regulation of Tyro3 and Mer mRNA and increased shedding of sTyro3 and sMer. Renal injury in diabetes is associated with elevated systemic and urine levels of sMer and sTyro3. This is the first study reporting excretion of sTAM receptors in urine, identifying the kidney as a source of sTAM.