Enhanced expression of complement C5a receptor mRNA in human diseased kidney assessed by in situ hybridization

Enhanced expression of complement C5a receptor mRNA in human diseased kidney assessed by in situ hybridization.BackgroundAnaphylatoxin C5a mediates inflammatory responses through interaction with a specific C5a receptor (C5aR), the expression of which is thought to be restricted to peripheral blood leukocytes. Although the presence of C5aR on cultured mesangial cells and tubular epithelial cells has recently been documented, the tissue distribution of C5aR in diseased kidney has not yet been determined.MethodsImmunohistochemistry and nonradioactive in situ hybridization for C5aR were performed in 34 tissue samples of kidneys from patients with various renal diseases, including 4 with minimal change nephrotic syndrome (MCNS), 5 with membranous nephropathy (MN), and 25 with mesangial proliferative glomerulonephritis (mesGN; 15 patients with IgA nephropathy, 5 with non-IgA mesGN, and 5 with lupus nephritis). Normal portions of surgically resected kidney served as the control.ResultsIn normal kidneys, C5aR protein was detected in tubular epithelial cells, while C5aR mRNA was detected in a few glomerular cells, tubular epithelial cells, and vascular endothelial and smooth muscle cells. In MCNS, the distribution of C5aR protein and mRNA was similar to that in normal kidneys. In MN and mesGN, C5aR protein and mRNA were detected in mesangial cells, glomerular epithelial and endothelial cells, Bowman's capsule cells, tubular cells, infiltrating cells, and vascular endothelial and smooth muscle cells. The glomerular expression of C5aR mRNA and protein correlated positively with the degree of mesangial hypercellularity and mesangial matrix expansion in mesGN. In the tubulointerstitium, interstitial expression of C5aR mRNA correlated positively with the degree of tubular atrophy and interstitial broadening in mesGN. Furthermore, the interstitial expression of C5aR mRNA correlated positively with the level of serum creatinine.ConclusionsOur results indicate that renal cells produce C5aR and that activation of C5a/C5aR pathway on renal cells may be involved in tissue injury in mesGN

Thalidomide Prevents the Progression of Peritoneal Fibrosis in Mice

Thalidomide is clinically recognized as a therapeutic agent for multiple myeloma and has been known to exert anti-angiogenic actions. Recent studies have suggested the involvement of angiogenesis in the progression of peritoneal fibrosis. The present study investigated the effects of thalidomide on the development of peritoneal fibrosis induced by injection of chlorhexidine gluconate (CG) into the mouse peritoneal cavity every other day for 3 weeks. Thalidomide was given orally every day. Peritoneal tissues were dissected out 21 days after CG injection. Expression of CD31 (as a marker of endothelial cells), proliferating cell nuclear antigen (PCNA), vascular endothelial growth factor (VEGF), α-smooth muscle actin (as a marker of myofibroblasts), type III collagen and transforming growth factor (TGF)-β was examined using immunohistochemistry. CG group showed thickening of the submesothelial zone and increased numbers of vessels and myofibroblasts. Large numbers of VEGF-, PCNA-, and TGF-β-positive cells were observed in the submesothelial area. Thalidomide treatment significantly ameliorated submesothelial thickening and angiogenesis, and decreased numbers of PCNA- and VEGF-expressing cells, myofibroblasts, and TGF-β-positive cells. Moreover, thalidomide attenuated peritoneal permeability for creatinine, compared to the CG group. Our results indicate the potential utility of thalidomide for preventing peritoneal fibrosis

A case of reversible posterior leukoencephalopathy syndrome in a patient on peritoneal dialysis.

Reversible posterior leukoencephalopathy syndrome (RPLS) is a recently identified clinical and radiologic entity. The characteristic radiologic findings are bilateral gray and white matter edema in the posterior regions of the cerebral hemispheres. The typical clinical syndrome includes headache, confusion, visual symptoms, and seizures. RPLS most often occurs in the setting of hypertensive crisis, preeclampsia, or with cytotoxic immunosuppressive therapy, but many other clinical settings are described, such as cryoglobulinemia, hemolytic uremic syndrome, systemic lupus erythematosus, and use of erythropoietin. A 24-year-old man, diagnosed as having anaphylactoid purpura nephritis at 12 years of age and who started peritoneal dialysis (PD) at 23 years of age, was admitted to our hospital with a seizure and consciousness disturbance. His blood pressure (BP) and body fluid volume had not been controlled well because of poor compliance with medication and PD. T2-weighted magnetic resonance imaging (MRI) revealed high signal intensity changes restricted to the cortex and subcortical white matter of the cerebellum. On the other hand, diffusion-weighted imaging showed an isointense signal. From these findings, he was diagnosed as having RPLS. With appropriate control of BP and volume control by PD and hemodialysis, his symptoms improved, and a follow-up cranial MRI 1 month later was almost normal. To the best of our knowledge, this is the first report of RPLS in an adult PD patient

Involvement of Leptin in the Progression of Experimentally Induced Peritoneal Fibrosis in Mice

013LeptinThe isJapana hormoneSociety mainlyof Histochemistryproduced byandwhite adipose cells, and regulates body fat and food intake by acting on hypothalamus. Leptin receptor is expressed not only in the hypothalamus but in a variety of peripheral tissues, suggesting that leptin has pleiotropic functions. In this study, we investigated the effect of leptin on the progression of peritoneal fibrosis induced by intraperitoneal injection of chlorhexidine gluconate (CG) every other day for 2 or 3 weeks in mice. This study was conducted in male C57BL/6 mice and leptin-deficient ob/ob mice. Peritoneal fluid, blood, and peritoneal tissues were collected 15 or 22 days after CG injection. CG injection increased the level of leptin in serum and peritoneal fluid with thickening of submesothelial compact zone in wild type mice, but CG-injected ob/ob mice attenuate peritoneal fibrosis, and markedly reduced the number of myofibroblasts, infiltrating macrophages, and blood vessels in the thickened submesothelial area. The 2-week leptin administration induced a more thickened peritoneum in the CG-injected C57BL/6 mice than in the PBS group. Our results indicate that an upregulation of leptin appears to play a role in fibrosis and inflammation during peritoneal injury, and reducing leptin may be a therapeutically potential for peritoneal fibrosis

Imaging mass spectrometry analysis reveals an altered lipid distribution pattern in the tubular areas of hyper-IgA murine kidneys.

Immunoglobulin A (IgA) nephropathy is the most common glomerular disease worldwide. To investigate the pathogenesis of this renal disease, we used animal models that spontaneously develop mesangioproliferative lesions with IgA deposition, which closely resemble the disease in humans. We analyzed the molecular distribution of lipids in hyper-IgA (HIGA) murine kidneys using matrix-assisted laser desorption/ionization-quadrupole ion trap-time of flight (MALDI-QIT-TOF)-based imaging mass spectrometry (IMS), which supplies both spatial distribution of the detected molecules and allows identification of their structures by their molecular mass signature. For both HIGA and control (Balb/c) mice, we found two phosphatidylcholines, PC(16:0/22:6) and PC(18:2/22:6), primarily located in the cortex area and two triacylglycerols, TAG(16:0/18:2/18:1) and TAG(18:1/18:2/18:1), primarily located in the hilum area. However, several other molecules were specifically seen in the HIGA kidneys, particularly in the tubular areas. Two HIGA-specific molecules were O-phosphatidylcholines, PC(O-16:0/22:6) and PC(O-18:1/22:6). Interestingly, common phosphatidylcholines and these HIGA-specific ones possess 22:6 lipid side chains, suggesting that these molecules have a novel, unidentified renal function. Although the primary structure of the HIGA-specific molecules corresponding to m/z 854.6, 856.6, 880.6, and 882.6 remained undetermined, they shared similar fragmentation patterns, indicating their relatedness. We also showed that all the HIGA-specific molecules were derived from urine, and that artificial urinary stagnation-due to unilateral urethral obstruction-caused HIGA-specific distribution of lipids in the tubular area

Multiple bone fracture due to Fanconi\u27s syndrome in primary Sjogren\u27s syndrome complicated with organizing pneumonia.

A 66-year-old woman showing renal dysfunction with elevated serum alkaline phosphatase and anti-SS-A antibody was admitted. A labial salivary gland biopsy showing infiltration of mononuclear cells and positive anti-SS-A antibody with sicca symptoms led to a diagnosis of primary Sjogren\u27s syndrome (SS). Fanconi\u27s syndrome was diagnosed by renal tubular acidosis along with renal glucosuria or aminoaciduria and multiple bone fractures on bone scintigraphy. Typical bilateral pulmonary shadows were confirmed as organizing pneumonia (OP) determined by the analysis of bronchoalveolar lavage fluid and transbronchial lung biopsy. A rare complication of Fanconi\u27s syndrome with OP in SS is described

Epigallocatechin gallate suppresses peritoneal fibrosis in mice.

Long-term peritoneal dialysis (PD) leads to histological changes in the peritoneal membrane. Angiogenesis and inflammation caused by glucose degradation products (GDPs) play crucial roles in peritoneal fibrosis. One such GDP is methylglyoxal (MGO), which enhances the formation of advanced glycation end products (AGEs). AGEs bind to their receptor (RAGE) and activate nuclear factor-κB (NF-κB), which is a key regulator of angiogenesis and inflammation. Recent studies have indicated that (-)-epigallocatechin gallate (EGCG), a tea polyphenol, inhibits angiogenesis and inflammation. Here, we examined whether EGCG suppresses peritoneal fibrosis in mice. Based on preliminary examination, 2mL of 40mM MGO or PD fluid was injected intraperitoneally and EGCG (50mg/kg) or saline was injected subcutaneously for 3weeks. In comparison to PD fluid+saline-treated mice, the peritoneal tissues of MGO+saline-treated mice showed marked thickening of the submesothelial compact zone. In the submesothelial compact zone of the MGO+saline-treated mice, CD31-positive vessels and vascular endothelial growth factor-positive cells were significantly increased, as were inflammation, F4/80-positive macrophages, and monocyte chemotactic protein-1. Moreover, 8-hydroxydeoxyguanosine, a marker of reactive oxygen species, and NF-κB, determined by Southwestern histochemistry, in the submesothelial compact zone were also increased in MGO+saline-treated mice. These changes were attenuated in MGO+EGCG-treated mice. We demonstrated that EGCG treatment suppresses peritoneal fibrosis via inhibition of NF-κB. Furthermore, EGCG inhibits reactive oxygen species production. The results of this study indicate that EGCG is a potentially novel candidate for the treatment of peritoneal fibrosis

Production and degradation of extracellular matrix in reversible glomerular lesions in rat model of habu snake venom-induced glomerulonephritis

We investigated the mechanism of development and repair process of glomerular injury in a rat model of habu snake (Trimeresurus flavoviridis) venom (HSV)-induced glomerulonephritis. Glomerulonephritis was induced in rats by intravenously injecting HSV at 3 mg/kg. Renal tissue was isolated and subjected to immunohistochemical analysis for expression levels of type IV collagen, heat shock protein 47 (HSP47), transforming growth factor-β (TGF-β), and matrix metalloproteinase-3 (MMP-3), as well as its transcription factor Ets-1. Expression levels of HSP47, TGF-β, and type IV collagen began to increase in the mesangial area starting from day 14 and peaked on day 21, followed by a gradual decrease. Expression levels of MMP-3 and Ets-1 started to increase coinciding with peak production of mesangial matrix on day 21, peaking on day 35, followed by gradual decrease. Expression of MMP-3 and Ets-1 persisted until day 63, whereas that of HSP47 and type IV collagen returned to baseline level at this time point. Time-course changes of extracellular matrix (ECM) accumulation in glomeruli in the HSV-induced glomerulonephritis model were correlated with those of factors involved in both ECM production and degradation systems. Continued expression of factors in the degradation system seems particularly important for the repair process. These findings might lead to new therapies that prevent and repair glomerular injury

Cowfish (Umisuzume, Lactoria diaphana) Poisoning with Rhabdomyolysis

A 40-year-old man developed weakness and myalgia of the shoulders and brachia nine hours after eating a cowfish (Umisuzume, Lactoria diaphana). A clinical symptom showed rhabdomyolysis and serum creatine phosphokinase was elevated to 180,000 IU/L on day 3. Cardiopulmonary arrest and acute renal failure developed after 59 hours and hemodiafiltration was performed. Cerebral death was diagnosed on day 9 and the patient died on day 16. The case has the characteristic clinical course of palytoxin poisoning, which has also been reported as blue humphead parrotfish poisoning from other kinds of fish