The Role of Cytokine in the Lupus Nephritis

Lupus nephritis (LN) is a major clinical manifestation of systemic lupus erythematosus (SLE). Although numerous abnormalities of immune system have been proposed, cytokine overexpression plays an essential role in the pathogenesis of LN. In the initial phase of the disease, the immune deposits and/or autoantibodies induce cytokine production in renal resident cells, leading to further inflammatory cytokine/chemokine expression and leukocyte infiltration and activation. Then, infiltrate leukocytes, such as macrophages (Mφ) and dendritic cells (DCs), secrete a variety of cytokines and activate naïve T cells, leading the cytokine profile towards T helper (Th)1, Th2, and/or Th17. Recent studies revealed these inflammatory processes in experimental animal models as well as human LN. The cytokine targeted intervention may have the therapeutic potentials for LN. This paper focuses on the expression of cytokine and its functional role in the pathogenesis of LN

Thermoelectric transport of perfectly conducting channels in two- and three-dimensional topological insulators

Topological insulators have gapless edge/surface states with novel transport properties. Among these, there are two classes of perfectly conducting channels which are free from backscattering: the edge states of two-dimensional topological insulators and the one-dimensional states localized on dislocations of certain three-dimensional topological insulators. We show how these novel states affect thermoelectric properties of the systems and discuss possibilities to improve the thermoelectric figure of merit using these materials with perfectly conducting channels.Comment: 10 pages, 6 figures, proceedings for The 19th International Conference on the Application of High Magnetic Fields in Semiconductor Physics and Nanotechnology (HMF-19

Fibrocytes: A new insight into kidney fibrosis

金沢大学医学部附属病院血液浄化療法部Fibrocytes are supposed to be a circulating connective tissue cell progenitor, which consists of a novel population of peripheral blood cells. This distinct population of blood-borne cells shares markers of leukocytes as well as mesenchymal cells. Accumulating evidence indicates that fibrosis is characteristic of progressive chronic kidney diseases of any etiologies, resulting in kidney failure. We have uncovered that CCR7-positive fibrocytes migrate into the kidney in response to secondary lymphoid tissue chemokine (SLC/CCL21) and contribute to kidney fibrosis induced by unilateral ureteral obstruction in mice. In addition, the blockade of CCL21/CCR7 signaling by anti-CCL21 antibodies reduced kidney fibrosis, which was confirmed by a decrease in fibrosis in CCR7-null mice with concomitant reduction in macrophage recruitment along with reduced renal transcripts of monocyte chemoattractant protein-1 (MCP-1/CCL2). These findings suggest that fibrocytes dependent on CCL21/CCR7 signaling pathways contribute to the pathogenesis of kidney fibrosis, thereby providing that regulating fibrocytes may provide a novel therapeutic benefit for kidney fibrosis. © 2007 International Society of Nephrology

protective effect of EGCG on mouse islets

Purpose: Epigallocatechin 3-gallate (EGCG), a green tea polyphenol, has been shown to have anti-oxidant and anti-inflammatory effects in vitro and in vivo. The aim of this study was to investigate the effects and mechanism of EGCG on isolated pancreatic islets as pre-conditioning for pancreatic islet transplantation. Methods: The pancreatic islets were divided into two groups: an islet culture medium group (control) and an islet culture medium with EGCG (100 μM) group. We investigated the islet viability, Nrf2 expression, reactive oxygen species (ROS) production, and heme oxygenase-1 (HO-1) mRNA. Five hundred islet equivalents after 12 h of culture for the EGCG 100 μM and control group were transplanted under the kidney capsule of streptozotocin (STZ)-induced diabetic ICR mice. Results: The cell viability and insulin secretion ability in the EGCG group were preserved, and the nuclear translocation of Nrf2 was increased in the EGCG group (p<0.01). While the HO-1 mRNA levels were also higher in the EGCG group than in the control group (p<0.05), the ROS production was lower (p<0.01). An in vivo functional assessment showed that the blood glucose level had decreased in the EGCG group after transplantation (p<0.01). Conclusion: EGCG protects the viability and function of islets by suppressing ROS production via the Nrf2 pathway

TAK-603, an anti-inflammatory compound, reduces crescentic glomerulonephritis and preserves renal function in WKY rats

金沢大学医学部附属病院血液浄化療法部Background. The therapeutic efficacy of the regulation of T helper (Th)-1-predominant immune responses remains to be investigated. Therefore, the effects of the anti-inflammatory compound TAK-603 were investigated in a model of crescentic glomerulonephritis induced by a small dose of nephrotoxic serum in Wistar-Kyoto rats. Methods. TAK-603 (50 mg/kg body weight) was administered orally, starting at the time of induction of glomerulonephritis. In group 1, the drug was administered daily for the initial 6 days. TAK-603 was administered on day 0 only in group 2, and from day 3 to 5 in group 3. In each group, nephritic rats were killed on days 6 and 56. Results. In group 1 consisting of rats treated with TAK-603 daily from day 0 to 5, glomerular damage, including crescent formation, was improved on day 6, with reductions in the numbers of CD4, CD8 and ED-1 positive cells, as well as in urinary protein excretion. Protein and transcript levels of Th1 cytokines in the diseased kidneys were markedly decreased by TAK-603 treatment. Renal pathology, including glomerulosclerosis and interstitial fibrosis, was ameliorated and proteinuria was markedly decreased. Elevated levels of serum creatinine showed concomitant improvement. In group 3, in which treatment was initiated shortly after the appearance of glomerular abnormalities, glomerular damage was also diminished, resulting in a decrease in urinary protein excretion. Treatment only on the first day in group 2, partially rescued renal dysfunction. Conclusions. These results suggest the possible therapeutic application of inhibition of Th1-predominant immune responses in progressive crescentic glomerulosclerosis. © 2006 Oxford University Press

Blockade of VEGF accelerates proteinuria, via decrease in nephrin expression in rat crescentic glomerulonephritis

金沢大学医学部附属病院血液浄化療法部Vascular endothelial growth factor (VEGF) is a potent angiogenic factor that maintains the glomerular and peritubular capillary (PTC) network in the kidney. The soluble form of the VEGF receptor-1 (soluble fms-like tyrosine kinase 1 (sFlt-1)) is known to regulate VEGF activity by binding VEGF in the circulation. We hypothesized that VEGF may be beneficial for maintaining glomerular filtration barrier and vascular network in rats with progressive glomerulonephritis (GN). For blockade of VEGF activity in vivo, rats were transfected twice with plasmid DNA encoding the murine sFlt-1 gene into femoral muscle 3 days before and 2 weeks after the induction of antiglomerular basement membrane antibody-induced GN. Inhibition of VEGF with sFlt-1 resulted in massive urinary protein excretion, concomitantly with downregulated expression of nephrin in nephritic rats. Further, blockade of VEGF induced mild proteinuria in normal rats. Administration of sFlt-1 affected neither the infiltration of macrophages nor crescentic formation. In contrast, treatment of sFlt-1 accelerated the progression of glomerulosclerosis and interstitial fibrosis accompanied with renal dysfunction and PTC loss at day 56. VEGF may play a role in maintaining the podocyte function as well as renal vasculature, thereby protecting glomeruli and interstitium from progressive renal insults. ﾂｩ 2006 International Society of Nephrology

Clinical impact of albuminuria in diabetic nephropathy

金沢大学医薬保健研究域医学系Patients suffering from diabetic nephropathy, resulting in end-stage renal failure, are increasing in number. The pathophysiology of diabetic nephropathy remains to be fully investigated. In the clinical setting, the presence of albuminuria/overt proteinuria and a low glomerular filtration rate may predict poor renal prognosis, but the prognosis of the normoalbuminuric renally insufficient diabetic patient remains controversial. In addition to the measurement of urinary albumin excretion, biomarker studies to detect diabetic nephropathy more specifically at the early stage have been performed worldwide. There is a growing body of evidence for remission and/or regression of diabetic nephropathy, which may be an indicator for cardiovascular and renal risk reduction. Deeper insights into the pathological characteristics as well as the clinical impact of albuminuria on renal and cardiovascular outcome are required. © 2011 Japanese Society of Nephrology

Involvement of bone-marrow-derived cells in kidney fibrosis

金沢大学医薬保健研究域医学系Cellular mechanisms have been proposed in the pathogenesis of fibrotic processes in the kidney. In this setting, cell sources underlying the generation of matrix-producing cells in diseased kidneys have been categorized as activated resident stromal cells (e.g., fibroblasts, pericytes), infiltrating bone-marrow-derived cells (e.g., fibrocytes, T cells, macrophages), and cells derived from epithelial-mesenchymal transition/endothelial-mesenchymal transition. Among these cell sources, accumulating evidence has shed light on the involvement of bone-marrow-derived cells, including monocytes/macrophages, and a circulating mesenchymal progenitor cell, fibrocyte, in the progression of fibrosis in kidney. Bone-marrow-derived cells positive for CD45 or CD34, and type 1 (pro)collagen dependent on the chemokine and renin-angiotensin systems migrate into diseased kidneys and enhance synthesis matrix protein, cytokines/chemokines, and profibrotic growth factors, which may promote and escalate chronic inflammatory processes and possible interaction with resident stromal cells, thereby perpetuating kidney fibrosis. © 2010 Japanese Society of Nephrology