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Objective. Intra-renal T cells and macrophages play a key pathogenic role in the development and progression of glomerular crescents. We aimed to establish (S)-armepavine [(S)-ARM], a major bioactive compound of a Chinese medicinal plant, Nelumbo nucifera, as a potential therapeutic agent in the treatment of autoimmune crescentic glomerulonephritis (ACGN). [ABSTRACT FROM PUBLISHER]

Background. Focal segmental glomerulosclerosis (FSGS) is caused by gradual deposition of extracellular matrix proteins, one of which, fibronectin (FN) is critical for sclerosis development. The origin of the FN deposited at an early stage of FSGS is still unclear.Methods. For investigating the origin of FN, the onset of increases in FN levels in the serum, glomeruli and urine were studied in a mouse model induced by adriamycin and compared with the time-course of development of glomerulosclerosis and expression of FN mRNA.Results. In the FSGS mice, serum FN levels were significantly increased as early as the onset of proteinuria on day 4 (7.26±0.37 mg/ml compared with 5.58±0.76 mg/ml in normal controls, P<0.05). This was followed by an increase in glomerular deposition of FN protein on day 7 (FN/actin ratio, 0.216±0.003 compared with 0.039±0.009 in normal controls, P<0.05). Glomerular m-RNA expression was also significantly elevated on day 7, but the locally synthesized FN did not show any increase until day 15. A significant increase in urinary FN protein and focal glomerulosclerosis was seen on day 11.Conclusions. We infer that FN in blood acts as an initiator of the development of FSGS in this mouse model. In addition, serum and urine FN proteins could serve as useful biomarkers for monitoring the progression of FSGS. [ABSTRACT FROM AUTHOR]

Background. We examined the alterations in gene expression associated with the development of crescentic glomerulonephritis in murine chronic graft-versus-host disease, a model for human systemic lupus erythematosus.Methods. The disease was induced in (C57BL/6 × DBA/2) F1 hybrids by injection of DBA/2 lymphocytes leading to deposition of auto-antibodies in the glomeruli, and a lupus type of nephritis morphologically. After extensive crescent formation at week 9 of disease, cDNA microarray analysis was performed and highly expressed genes were evaluated as molecular markers by real-time reverse transcription–polymerase chain reaction (RT–PCR), in situ hybridization, immunohistochemistry and immunoassay of urine proteins.Results. Six genes, secreted acidic cysteine-rich glycoprotein (Sparc), thymosin beta 10 (Tmsb10), S100 calcium-binding protein A6 (S100a6), annexin A2 (Anxa2), osteopontin (OPN) and lipocalin 2 (Lcn2), were quantified by real-time RT–PCR in laser microdissected glomeruli in a time course manner. Sparc was detected early before the onset of proteinuria and continued to increase throughout the course of the disease. The expression of Tmsb10, S100a6 and Anxa2 coincided with heavy proteinuria. By week 9, OPN and Lcn2 were highly expressed. The expression of proteins encoded by these genes was predominant in the glomerular crescent. The protein levels of Sparc, OPN and Lcn2 in urine were significantly elevated.Conclusions. These findings implicate these six genes in the development of glomerular crescents. More importantly, detection of Sparc, OPN and Lcn2 in urine may mean that these molecules could serve as important biomarkers for non-invasive diagnosis of glomerular crescents. [ABSTRACT FROM AUTHOR]

Hyperglycemia and mannitol activate protein kinase C (PKC) and induce mesangial cell hypocontractility that subsequently may modulate renal function. Since focal adhesion kinase (FAK) activation is known to be linked with PKC activity, FAK may also be involved in mesangial cell contraction. To facilitate our understanding of the PKC- and FAK-modulating mechanism, we developed an in vitro model of mouse mesangial cell hypocontractility induced by hyperglycemia or mannitol. Mouse mesangial cells (CRL-1927) were exposed to: normal D -glucose (group N), high D -glucose (group H), and control groups at the same osmolality as H plus L -glucose (group L) and mannitol (group M). Changes in the planar surface area of cells in response to 1 μM phorbol 12-myristate 13-acetate (PMA) were determined. Western blot analyses for PKC, phosphorylated (p)-PKC, tyrosine phosphorylation, FAK, and p-FAK were done on each of these four groups. The effects of mannitol in various doses on cell contraction and activation of PKC and FAK were also assayed. The planar surface areas of groups H and M both showed an attenuated change in response to PMA stimulation. Before PMA stimulation, the baseline PKC expression of groups H and M showed a higher expression of p-PKCα and δ than that seen in group N (p < 0.05). Results of tyrosine phosphorylation and immunoprecipitation showed that FAK may be involved in this contraction process. The total amount of FAK showed no significant difference among the four experimental groups; however, p-FAK was found to have significantly increased in group M (p < 0.05). The use of PKC and tyrosine kinase inhibitors reduced PMA-induced mesangial cell contraction in all four groups. Activation of PKCα, δ, and FAK with the resultant inhibition of mesangial cell contraction by mannitol was found to be dose-dependent. These results may provide a correlation between increased expression of several PKC isoforms and, in particular, increased phosphorylation levels of PKCα and δ and hypocontractility induced by high glucose and mannitol treatment. Furthermore, the mannitol-induced hypocontractility involving PKC and FAK occurred in a dose-dependent manner. Copyright © 2004 National Science Council, ROC and S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background. Rab23, a member of the Rab family of small GTPase, has a function in antagonizing sonic hedgehog signal transduction. Both Rab-family and hedgehog-related proteins are involved in sclerosis and fibrosis in certain pathological states, but their roles in focal segmental glomerulosclerosis (FSGS) remain unclear. Methods. The FSGS model was established in Balb/c mice by a single injection of adriamycin. Serum, urine and mice kidneys were collected on Days 0, 7, 15 and 20. Western blot analysis was performed to detect the levels of Rab23 in the samples. Immunohistochemistry was used to examine the expressional profiles of Rab23 in kidneys. The expressions of transcripts of Rab23, extracellular matrix (ECM) proteins, and various hedgehog signalling pathway genes in kidneys or mesangial cells were evaluated by real-time RT-PCR. The effect of Rab23 on ECM protein expressions was evaluated by the knockdown or overexpression of Rab23 in mesangial cells. Results. Our results show that elevations of Rab23 were observed in the urine, but not in the serum, of the FSGS mice. Rab23 and hedgehog signalling pathway genes were constitutively expressed in normal kidneys and were significantly up-regulated in the kidneys of FSGS mice. The basal expression of Rab23 was identified in glomeruli, and mesangial cells displayed obvious elevation of Rab23 in the FSGS state. The knockdown or overexpression of Rab23 affected the collagen expression in cultured mesangial cells. Conclusions. An autocrine loop of hedgehog signalling could be activated in mesangial cells in the FSGS state, and Rab23 may be elevated to suppress hedgehog signalling and/or influence collagen synthesis. Importantly, Rab23 could serve as a biomarker that indicates the severity of FSGS. [ABSTRACT FROM AUTHOR]

Background. Acute tubular necrosis (ATN) is characterized by an initiation phase, followed by an extension phase, and a maintenance and recovery phase, the latter of which involves increased regeneration of tubular cells. Nephronectin (NPNT), a ligand for α8β1 integrin, is expressed in the ureteric bud epithelium during kidney morphogenesis. However, little is known about the potential involvement of NPNT in the regeneration phase of ATN. Methods. cDNA microarray, real-time polymerase chain reaction, in situ hybridization, immunohistochemistry, immuno-electron microscopy and immunoassay (for urine) were used to identify the time-course NPNT expression in a murine model of ATN. Results. The gene transcript of NPNT was examined during a 14-day course of ATN by a cursory cDNA microarray analysis. Although NPNT was observed focally in normal renal tubular epithelium, it was greatly expressed in regenerating tubular cells during the maintenance and recovery phases of ATN. As early as day 1 following onset of ATN, NPNT was already present in the urine. Importantly, NPNT expression preceded proliferating cell nuclear antigen protein expression in regenerating renal tubular epithelial cells, as demonstrated by double immunohistochemistry. Conclusion. The present study was the first to identify an enhanced expression of NPNT in regenerating tubular epithelium in an experimental model of ATN. NPNT may play a crucial role in the regenerating process of nephrotoxic ATN. Our data also suggest that NPNT may provide a useful tissue and urine biomarker for both the development and evolution of nephrotoxic acute renal injury. [ABSTRACT FROM AUTHOR]

Background. Focal segmental glomerulosclerosis (FSGS) is a chronic nephropathy showing characteristic glomerular sclerosis. So far, the diagnosis and prognosis of FSGS rely mainly on the invasive biopsy. Searching for potential FSGS-associated urinary biomarkers representing pre-sclerotic and serial sclerotic stages of FSGS could be helpful to the non-invasive diagnosis and prognosis of FSGS. Methods. In the present study, we used a 2D gel-based proteomic approach to identify urinary proteins at pre-sclerotic and different sclerotic stages of an FSGS mouse model in order to find FSGS-related urinary proteins. The FSGS mouse model was established in Balb/c mice by a single injection of adriamycin, and disease severity was monitored by renal biological parameters and histopathological features. Urine was collected on days 0, 4, 7, 11, 15 and 20, and subjected to two-dimensional electrophoresis (2-DE) analysis. Proteins were identified by matrix-assisted laser desorption ionization/time of flight mass spectrometry (MALDI-TOF MS) and a protein database search. Some of the identified proteins were confirmed by western blot analysis. Results. We identified 37 urinary proteins showing characteristic patterns of dynamic changes along the disease course of FSGS. Early urinary proteins appearing before glomerular scleoris were noticed. Importantly, 11 urine proteins are novel to FSGS and have known functions highly associated with different pathogenetic steps of the disease, including haemodynamic disturbance, podocyte apoptosis, ECM-protein deposition and glomerular sclerosis. Conclusions. Some urinary proteins appearing earlier than glomerular sclerosis could serve as potential early diagnostic biomarkers. The proteins with the pathogenic roles could serve as potential non-invasive prognostic markers of FSGS, and give an insight into pathogenic mechanisms of this sclerosis disease. [ABSTRACT FROM AUTHOR]

Background. Rise in cellular calcium is associated with acute tubular necrosis, the most common cause of acute renal failure (ARF). The mechanisms that calcium signaling induce in the quiescent tubular cells to proliferate and differentiate during acute tubular necrosis have not been elucidated. Methods. Acute tubular necrosis induced in mice by single intravenous injection of uranyl nitrate and examined after 1, 3, 7, and 14 days. Renal function was monitored and kidneys were evaluated by histology, immunohistochemistry, Western blotting, in situ hybridization, and real-time reverse transcription-polymerase chain reaction (RT-PCR). Models of folic acid induced-ARF and ischemic/reperfusion (I/R) injury were similarly investigated. Results. Analysis of mRNA expression of intracellular calcium and phospholipid-binding proteins demonstrated selective expression of S100A6 and Annexin A2 (Anxa2) in the renal cortex with marked elevation on day 3, and gradually decline on day 7 and further attenuation on day 14. Similarly, the expression of both proteins, as demonstrated by immunohistochemistry and Western blot analysis, was increased and reached the peak level on day 7 and then gradually declined by day 14. Vimentin, a marker of dedifferentiated cells, was highly expressed during the recovery phase. Combined in situ hybridization immunohistochemistry revealed colocalization of both S100A6 and Anxa2 with proliferating cell nuclear antigen (PCNA). The universality of this phenomenon was confirmed in two other mouse acute tubular necrosis models, the ischemic-reperfusion injury and folic acid-induced ARF. Conclusion. Collectively, these findings demonstrate that S100A6 and Anxa2 expression, initiated in response to tubular injury, persist in parallel throughout the recovery process of tubular cells in acute renal failure. [ABSTRACT FROM AUTHOR]

IgA nephropathy (IgAN), the most common primary glomerular disorder, has a relatively poor prognosis yet lacks a pathogenesisbased treatment. Compound K (CK) is a major absorbable intestinal bacterial metabolite of ginsenosides, which are bioactive components of ginseng. The present study revealed promising therapeutic effects of CK in two complementary IgAN models: a passively induced one developed by repeated injections of IgA immune complexes and a spontaneously occurring model of spontaneous grouped ddY mice. The potential mechanism for CK includes 1) inhibiting the activation of NLRP3 inflammasome in renal tissues, macrophages and bone marrow-derived dendritic cells, 2) enhancing the induction of autophagy through increased SIRT1 expression, and 3) eliciting autophagy-mediated NLRP3 inflammasome inhibition. The results support CK as a drug candidate for IgAN. [ABSTRACT FROM AUTHOR]

Tris (dibenzylideneacetone) dipalladium (Tris DBA), a small-molecule palladium complex, has been shown to inhibit cell growth and proliferation in pancreatic cancer, lymphocytic leukemia, and multiple myeloma. In the current study, we examined the therapeutic effects of Tris DBA on glomerular cell proliferation, renal inflammation, and immune cells. Treatment of accelerated and severe lupus nephritis (ASLN) mice with Tris DBA resulted in improved renal function, albuminuria, and pathology, including measurements of glomerular cell proliferation, cellular crescents, neutrophils, fibrinoid necrosis, and tubulointerstitial inflammation in the kidneys as well as scoring for glomerulonephritis activity. The treated ASLN mice also showed significantly decreased glomerular IgG, IgM, and C3 deposits. Furthermore, the compound was able to 1) inhibit bone marrow-derived dendritic cell-mediated T cell functions and reduce serum anti-dsDNA autoantibody levels; 2) differentially regulate autophagy and both the priming and activation signals of the NLRP3 inflammasome; and 3) suppress the phosphorylation of JNK, ERK, and p38 MAPK signaling pathways. Tris DBA improved ASLN in mice through immunoregulation by blunting the MAPK (ERK, JNK)-mediated priming signal of the NLRP3 inflammasome and by regulating the autophagy/NLRP3 inflammasome axis. These results suggest that the pure compound may be a drug candidate for treating the accelerated and deteriorated type of lupus nephritis. [ABSTRACT FROM AUTHOR]

The Osmanthus fragrans flower, a popular herb in Eastern countries, contains several antioxidant compounds. Ben Cao GangMu, traditional Chinese medical literature, describes the usefulness of these flowers for phlegm and stasis reduction, arrest of dysentery with blood in the bowel, and stomachache and diarrhea treatment. However, modern evidence regarding the therapeutic efficacy of these flowers is limited. This study was aimed at assessing the antioxidative effects of the ethanol extract of O. fragrans flowers (OFE) in vivo and evaluating its antioxidant maintenance and therapeutic effect on an allergic airway inflammation in mice. After OFE's oral administration to mice, the values obtained in the oxygen radical absorbance capacity assay as well as the glutathione concentration in the lungs and spleens of mice increased while thiobarbituric acid reactive substances decreased significantly, indicating OFE's significant in vivo antioxidant activity. OFE was also therapeutically efficacious in a mouse model of ovalbumin-induced allergic airway inflammation. Orally administered OFE suppressed ovalbumin-specific IgE production and inflammatory cell infiltration in the lung. Moreover, the antioxidative state of the mice improved. Thus, our findings confirm the ability of the O. fragrans flowers to reduce phlegm and suggest that OFE may be useful as an antiallergic agent. [ABSTRACT FROM AUTHOR]