Plasma CD147 reflects histological features in patients with lupus nephritis.

OBJECTIVE: A glycosylated transmembrane protein, CD147, has been implicated in regulating lymphocyte responsiveness and leukocyte recruitment. As lupus nephritis (LN) often follows a relapsing-remitting disease course, accurate understanding of the disease activity would be extremely helpful in improving prognosis. Unfortunately, neither clinical nor serological data can accurately reflect the histological features of LN. The present study investigated whether CD147 can accurately predict pathological features of LN. METHODS: Plasma and spot urine samples were collected from 64 patients who underwent renal biopsy between 2008 and 2011. Disease activity for LN tissues was evaluated using the biopsy activity index, and compared to levels of biomarkers including CD147. RESULTS: In LN tissues, CD147 induction was striking in injured glomeruli and infiltrating inflammatory cells, but not in damaged tubules representing atrophy. Plasma CD147 levels accurately reflected the histological disease activity. However, prediction using a single molecule would be quite difficult because of the complex pathogenesis of LN. The diagnostic accuracy of multiplex parameters indicated that the combination including plasma CD147 might yield excellent diagnostic abilities for guiding ideal LN therapy. CONCLUSION: Plasma CD147 levels might offer useful insights into disease activity as a crucial biomarker in patients with LN.

Effects of olmesartan on renal and cardiovascular outcomes in type 2 diabetes with overt nephropathy: a multicentre, randomised, placebo-controlled study.

AIMS/HYPOTHESIS: The renal and cardiovascular protective effects of angiotensin receptor blocker (ARB) remain controversial in type 2 diabetic patients treated with a contemporary regimen including an angiotensin converting enzyme inhibitor (ACEI). METHODS: We examined the effects of olmesartan, an ARB, on primary composite outcome of doubling of serum creatinine, endstage renal disease and death in type 2 diabetic patients with overt nephropathy. Secondary outcome included composite cardiovascular outcomes, changes in renal function and proteinuria. Randomisation and allocation to trial group were carried out by a central computer system. Participants, caregivers, the people carrying out examinations and people assessing the outcomes were blinded to group assignment. RESULTS: Five hundred and seventy-seven (377 Japanese, 200 Chinese) patients treated with antihypertensive therapy (73.5% [n = 424] received concomitant ACEI), were given either once-daily olmesartan (10-40 mg) (n = 288) or placebo (n = 289) over 3.2 ± 0.6 years (mean±SD). In the olmesartan group, 116 developed the primary outcome (41.1%) compared with 129 (45.4%) in the placebo group (HR 0.97, 95% CI 0.75, 1.24; p = 0.791). Olmesartan significantly decreased blood pressure, proteinuria and rate of change of reciprocal serum creatinine. Cardiovascular death was higher in the olmesartan group than the placebo group (ten vs three cases), whereas major adverse cardiovascular events (cardiovascular death plus non-fatal stroke and myocardial infarction) and all-cause death were similar between the two groups (major adverse cardiovascular events 18 vs 21 cases, all-cause deaths; 19 vs 20 cases). Hyperkalaemia was more frequent in the olmesartan group than the placebo group (9.2% vs 5.3%). CONCLUSIONS/INTERPRETATION: Olmesartan was well tolerated but did not improve renal outcome on top of ACEI. TRIAL REGISTRATION: ClinicalTrials.gov NCT00141453.

FGF-2 stimulates periodontal regeneration: results of a multi-center randomized clinical trial.

The efficacy of the local application of recombinant human fibroblast growth factor-2 (FGF-2) in periodontal regeneration has been investigated. In this study, a randomized, double-blind, placebo-controlled clinical trial was conducted in 253 adult patients with periodontitis. Modified Widman periodontal surgery was performed, during which 200 µL of the investigational formulation containing 0% (vehicle alone), 0.2%, 0.3%, or 0.4% FGF-2 was administered to 2- or 3-walled vertical bone defects. Each dose of FGF-2 showed significant superiority over vehicle alone (p < 0.01) for the percentage of bone fill at 36 wks after administration, and the percentage peaked in the 0.3% FGF-2 group. No significant differences among groups were observed in clinical attachment regained, scoring approximately 2 mm. No clinical safety problems, including an abnormal increase in alveolar bone or ankylosis, were identified. These results strongly suggest that topical application of FGF-2 can be efficacious in the regeneration of human periodontal tissue that has been destroyed by periodontitis.

Clinicopathological study of expression of lymphatic vessels in renal allograft biopsy after treatment for acute rejection.

BACKGROUND: Lymph vessel expression is related to inflammatory cell infiltration, around renal tubules in acute rejection episodes (ARE) of transplanted kidneys. However, there is little information on the lymph vessels after treatment of an ARE, particularly in relation to renal function and histological findings. PATIENTS AND METHODS: We investigated 13 cases of ARE diagnosed by kidney transplant biopsy performed from 1997 to 2005 within 3 years of transplantation. Treatment of the ARE lead to an improved serum creatinine level in all cases. There was neither an ABO-incompatible nor an acute humoral rejection case. Lymphatic vessels in re-biopsies were examined using immunohistochemical staining with D2-40 antibody that detected lymphatic endothelium. Re-biopsy cases in which the baseline creatinine had increased by more than 20% despite treatment were considered the severe group; the others, as the stable group. The relation between lymphatic vessel density (LVD) and renal function was examined using Banff scores. RESULTS: LVD was significantly higher in the severe than the stable group. The expression of lymph vessels versus the Banff score showed a direct relation: greater Banff scores showed higher expressions of lymph vessels. CONCLUSIONS: The expression of lymph vessels in renal allograft specimens after treatment of an ARE was related to deterioration of renal function and inflammatory cell invasion. We plan a further examination of the relationship between the expression of lymph vessels and long-term prognosis.

A clinicopathologic study of p27(kip1) expression in renal allograft biopsy.

BACKGROUND: P27 (Kip1) is an inhibitor of cyclin-dependent kinases/cyclin complex that keeps mature cells growth-arrested. In IgA nephropathy, a decreased p27kip1 expression in podocytes has been reported to be related to lesion formation of focal segmental glomerulosclerosis and renal dysfunction. We reviewed the p27kip1 expression in transplanted kidneys. METHODS: p27kip1 expression was examined immunohistochemically in 26 allograft biopsy specimens. RESULTS: p27kip1 expression was recognized in podocytes. Patients with more than 0.5 g proteinuria showed fewer p27kip1-positive cells than those with less than 0.5 g proteinuria. The decreased p27kip1 expression in podocytes was related to cg and ah of the Banff 97 classification. In the two cases in which p27kip1 expression was remarkably decreased, elevation of the serum creatinine level was recognized at the time of biopsy, resulting in kidney transplant loss. The histological findings were chronic/sclerosing allograft nephropathy grade II-(b) in both cases. CONCLUSION: In conclusion, decreased p27kip1 expression in podocytes suggested a significant role in proteinuria among renal transplant recipients.

Transcription factor Ets-1 is essential for mesangial matrix remodeling.

Most advanced glomerular diseases are characterized by abnormal extracellular matrix (ECM) accumulation in the glomeruli, and matrix metalloproteinases (MMPs) play a pivotal role in ECM remodeling in various glomerular diseases. The proto-oncogene, ets-1, is a transcription factor regulating the expression of various matrix proteinases, including MMP-1, MMP-3, and MMP-9. The goal of the present study was to characterize the role of Ets-1 in the progression of glomerular diseases. Overexpression of Ets-1 in cultured mesangial cells prevented transforming growth factor (TGF)-beta-induced inhibition of DNA-binding activity and TGF-beta-induced type I collagen production. In addition, exogenous Ets-1 abolished TGF-beta-induced collagen gel contraction. The in vivo transfection of the ets-1 gene into nephritic kidney resulted in the increases in glomerular MMP-1, MMP-3, and MMP-9 mRNA, decreases in mesangial ECM deposition, and attenuation of fibronectin extradomain A (EDA) and type I collagen expression. In contrast, knockdown of Ets-1 in glomeruli resulted in severe ECM deposition in diseased glomeruli. In conclusion, Ets-1 promotes degradation of ECM proteins and is critical for integral glomerular reorganization.

Growth-promoting effect on iron-sulfur proteins on axenic cultures of Entamoeba dispar.

A growth-promoting factor (GPF) that promotes the growth of Entamoeba dispar under axenic culture conditions was found in fractions of mitochondria (Mt), hydrogenosomes (Hg) and chloroplasts (Cp) obtained from cells of six different protozoan, mammalian and plant species. We were able to extract the GPF from the Cp-rich leaf cells of a plant (spiderwort: Commelina communis L.) in an acetone-soluble fraction as a complex of chlorophyll with low molecular weight proteins (molecular weight [MW] approximately 4,600). We also found that on treatment with 0.6% complexes of 2-mercapthoethanol (2ME), complexes of chlorophyll-a with iron-sulphur (Fe-S) proteins (e.g., ferredoxins [Fd] from spinach and Clostridium pasteurianum) and noncomplex rubredoxin (Rd) from C. posteurianum have a growth-promoting effect on E. dispar. These findings suggest that E. dispar may lack a sufficient quantity of some essential components of Fe-S proteins, such as Fe-S center.

Adenosine A1 receptor antagonist improves intradialytic hypotension.

Intradialytic hypotension is a most frequent complication of hemodialysis and may contribute to cardiovascular events and high mortality. There is a hypothesis that an increase in adenosine generation during hemodialysis may cause vasodilation and a decrease in cardiac output, which results in systemic hypotension. We studied whether this can be blocked by an adenosine A1 receptor antagonist. We investigated the effects of an A1 antagonist, FK352, injection in 30 chronic hemodialysis patients with frequent intradialytic hypotension by a prospective, multicenter, double-blind placebo-controlled study for 4 weeks after 4 weeks of the observation period. Intradialytic hypotension was defined as systolic blood pressure (SBP) less than 110 mmHg, with SBP drop of more than 30 mmHg from the predialysis level. The efficacy of FK352 was primarily assessed by the reduction rate of dialysis hypotension between the FK352 and placebo groups. Incidence of emergency treatments caused by hypotension was evaluated. FK352 (50 mg, intravenous) or an equivalent placebo was injected into the dialysis circuit 1 h after starting dialysis. Blood pressure and heart rate were monitored every 30 min during dialysis. FK352 significantly improved intradialytic hypotension (P=0.046), in that the reduction rates of intradialytic hypotension in the FK352 and placebo groups were -12.8% (Q1 (first quantile), Q3 (third quantile): -27.5, -1.7), and +8.3% (Q1, Q3: -16.6, +16.7), respectively. The frequency of discontinuation of dialysis was significantly reduced by FK352. No apparent side effects were observed from treatment with FK352. In conclusion, the A1 antagonist FK352 may offer a novel therapeutic option for chronic dialysis patients associated with intradialytic hypotension.

Increased expression of renin in chronic allograft nephropathy.

BACKGROUND: Chronic allograft nephropathy (CAN) is the main cause of renal transplant failure in the first decade posttransplant. The precise pathogenetic mechanism for CAN is not completely understood. A possible role of renin-angiotensin system for CAN has been suggested through clinical observations that angiotensin-converting enzyme inhibition and angiotensin II receptor blockers prevent CAN. METHODS: Distribution of renin-positive cells in allograft biopsy specimens was examined immunohistochemically in 23 renal transplant recipients diagnosed with CAN Biopsy specimens obtained from seven recipients with stable renal function were examined as controls. Histologic evaluation was performed based on the Banff 97 classification. RESULTS: Renin-positive cells were found in the juxtaglomerular apparatus (JGA) adjoining the afferent arterioles in both groups. When the number of renin-positive cells in JGA was defined as a renin index, it was significantly higher in the CAN than the control group (P = .007). There was no significant difference in age, interval between transplantation and biopsy, and blood pressure between groups. Only a significantly higher serum creatinine was found in the CAN group. CONCLUSIONS: The increased renin-positive cells in JGA suggest a significant role of the intrarenal renin-angiotensin system activation in the development of CAN.

Electroporation-mediated HGF gene transfection protected the kidney against graft injury.

The annual rate of kidney graft loss caused by chronic allograft nephropathy (CAN) has not improved over the past decade. Recent reports suggest that acute renal ischemia results in development of CAN. The goal of the present study was to assess the renoprotective potential and safety of hepatocyte growth factor (HGF) gene transfer using a porcine kidney transplant warm ischemia injury model. Following left porcine kidney removal, 10 min of warm ischemic injury was intentionally induced. Next, the HGF expression vector or vehicle was infused into the renal artery with the renal vein clamped ex vivo, and electric pulses were discharged using bathtub-type electrodes. Kidney grafts were then transplanted after removing the right kidney. Histopathological examination of vehicle-transfected kidney transplant revealed initial tubular injury followed by tubulointerstitial fibrosis. In contrast, HGF-transfected kidneys showed no initial tubular damage and no interstitial fibrosis at 6 months post-transplant. We conclude that electroporation-mediated ex vivo HGF gene transfection protects the kidney against graft injury in a porcine model.

Exploring RNA interference as a therapeutic strategy for renal disease.

The short synthetic interfering RNA duplexes (siRNAs) can selectively suppress gene expression in somatic mammalian cells without nonselective toxic effects of double-stranded RNA (dsRNA). However, a selective in vivo delivery of siRNA transfer has not been reported in kidney. Here, we investigated whether injection of synthetic siRNAs via renal artery followed by electroporation could be effective and therapeutic in silencing specific gene in glomerulus. We investigated the effect of siRNA in rat cultured mesangial cells (MCs) and showed that siRNA sequence-specific suppression of transgene expression was over a 1000-fold more potent than that by antisense oligodeoxynucleotide (ASODN). Transfection of siRNA targeting luciferase into rat kidneys significantly inhibited expression of a cotransfected luciferase expression vector in vivo. The delivery of siRNA targeting enhanced green fluorescent protein (EGFP) in the transgenic 'green' rat reduced endogenous EGFP expression, mainly in glomerular MCs. Furthermore, RNAi targeting against TGF-beta1 significantly suppressed TGF-beta1 mRNA and protein expression, thereby ameliorated the progression of matrix expansion in experimental glomerulonephritis. In addition, vector-based RNAi also inhibited TGF-beta1 expression in vitro and in vivo. In conclusion, siRNA-directed TGF-beta1 silencing may be of therapeutic value in the prevention and treatment of fibrotic diseases.

Risk factors for graft loss in patients with recurrent IGA nephropathy after renal transplantation.

BACKGROUND: The recurrence rate of IgA nephropathy (IgAN) in transplanted kidneys has been reported to be >50%. Although recurrent IgAN has a benign clinical course, recent data suggest that it leads to graft loss in a substantial number of patients. METHODS: We performed a retrospective single-center analysis of 34 renal transplant recipients, with biopsy-proven IgAN as the cause of end-stage renal failure. RESULTS: Renal allograft biopsies were performed in 30 patients, of whom 24 did and 6 did not have biopsy-confirmed recurrent transplant IgAN. Recurrent transplant IgAN was more often detected in men and at later timepoints after post-transplantation. Four patients with recurrent transplant IgAN progressed to graft failure. Progression to graft failure was associated with worsened renal function, higher systolic blood pressure, and the lack of presenation of angiotensin-converting enzyme inhibitors (ACEs) at the time of allograft biopsy. Immunologic factors such as frequency of acute rejection, HLA typing, and immunosuppression did not show a relation to recurrence or graft loss. CONCLUSIONS: Recurrent transplant IgAN increased with long-term graft survival and risk factors for graft loss due to recurrent IgAN were similar to those among IgAN in native kidneys.

Pharmacokinetics and lipid-lowering effect of fluvastatin in hypercholesterolaemic patients on maintenance haemodialysis.

Patients undergoing haemodialysis are predisposed to serum lipid abnormalities that can accelerate the development of atherosclerosis. Serum lipid levels must therefore be controlled over a long period. For patients with reduced renal function (including dialysis patients), special attention must be paid to hyperlipidaemia therapy, particularly drug selection. In this study, 30 mg/day fluvastatin was administered orally to five patients receiving maintenance haemodialysis. Their serum lipid levels and blood biochemistry were monitored during the 6 months of fluvastatin administration, and the pharmacokinetic parameters calculated. The therapeutic efficacy and safety of fluvastatin were demonstrated in this patient group. Furthermore, fluvastatin is not influenced by the dialysis membrane and does not accumulate in haemodialysis patients with hyperlipidaemia.

Introduction of DNA enzyme for Egr-1 into tubulointerstitial fibroblasts by electroporation reduced interstitial alpha-smooth muscle actin expression and fibrosis in unilateral ureteral obstruction (UUO) rats.

The phenotypic alteration of interstitial fibroblasts into 'myofibroblasts', acquiring characteristics of both fibroblasts and smooth muscle cells is a key event in the formation of tubulointerstitial fibrosis. The up-regulation of the early growth response gene 1 (Egr-1) preceded the increased interstitial expression of alpha-smooth muscle actin (alphaSMA), a marker of phenotypic changes, in obstructed kidney, a model of interstitial fibrosis. To target Egr-1 expression in the interstitium of obstructed kidneys, we introduced a DNA enzyme for Egr-1 (ED5) or scrambled DNA (SCR) into interstitial fibroblasts by electroporation-mediated gene transfer. Northern blot analysis confirmed an increase in the cortical mRNA expression of Egr-1 in the obstructed kidneys from untreated or SCR-treated rats, while ED5 transfection blocked Egr-1 expression with a concomitant reduction in TGF-beta, alphaSMA and type I collagen mRNA expression. Consequently, ED5 inhibited interstitial fibrosis. In conclusion, electroporation-mediated retrograde gene transfer can be an ideal vehicle into interstitial fibroblasts, and molecular intervention of Egr-1 in the interstitium may become a new therapeutic strategy for interstitial fibrosis.

Longitudinal distortions and transversal fluctuations of an actin filament sliding on Myosin molecules.

An actin filament sliding on myosin moleculesdemonstrates both longitudinal distortions and transversal fluctuationswith the linear dimension far exceeding the diameter of an actinmonomer. Local swaying of a single actin filament was identified byreading speckled fluorescent markers attached on the filament. Theaccuracy of reading each speckled marker was about 10.4 nm (r.m.s.).Longitudinal distortions of an actin filament at a low ATP concentrationof 20 µM were as much as 0.5 µm for the average filament lengthof 5.4 µm. The magnitude of transversal fluctuations was as much as60 nm, that was independent of the filament length. Both longitudinaldistortions and transversal fluctuations are suggested to play a pivotalrole for facilitating a smooth sliding movement of an actin filament.

Application of bone marrow-derived stem cells in experimental nephrology.

Recent advancement in developmental biology has led to the discovery of immature mesenchymal stem cells in bone marrow and several established organs. The therapeutic potentials of such stem cells for treating serious diseases constitute a major rationale for every research effort, and clinical trials for replacing some damaged tissues such as cartilage are currently under way. Although the feasibility of such stem cell therapies for renal diseases remains unknown, it is worthy of pursuing possibilities. As an experimental tool, we have made chimeric rats that carry the bone marrow of transgenic rats expressing green fluorescent protein (GFP) throughout the body. All marrow lineages can be traced with bright green fluorescence regardless of their terminal phenotypes in chimeric rats. When compared with other conventional strategies for tracking bone marrow-derived cells, our system is highly sensitive and allows us to take advantage of the rat nephrology. Using this system, we have reported that bone marrow provides mesangial cells during repair process. In this manuscript, we briefly summarize our experiences.

Significantly rapid relief from steroid-resistant nephrotic syndrome by LDL apheresis compared with steroid monotherapy.

Rapid amelioration of hypercholesterolemia by LDL apheresis (LDL-A) was performed for long-standing nephrotic syndrome (NS) with hyperlipidemia due to focal segmental glomerulosclerosis (FGS) and the clinical data and prognosis were compared between LDL-A-treated and nontreated groups. Seventeen steroid-resistant NS patients treated with LDL-A (LDL-A group) and 10 NS patients treated with steroids only (steroid-monotherapy (SM) group) were compared. Serum cholesterol and phospholipid levels were significantly lowered only in the LDL-A group (p < 0.01, respectively). The LDL-A group showed a significant decrease of urinary protein (UP, p < 0.01) and increase of serum albumin (p < 0.05). Average time needed to achieve a decrease of UP to less than nephrotic range (< 3.5 g/day) was significantly shorter in the LDL-A group than in the SM group (p < 0.01). Although this is not a prospective study, it is highly expected that a rapid improvement of hypercholesterolemia by LDL-A in steroid-resistant NS will provide more rapid relief from NS than steroid therapy alone.

Gene therapy approach in renal disease in the 21st century.

Theoretically, gene therapy has distinct potential to treat renal disease at the most fundamental level. However, the ability to pursue gene therapy has been limited by the availability of an adequate system for gene delivery to the kidney. The present viral vector systems seem to have limitations for clinical use because of uncertainty regarding their toxicity and immunogenicity; however, adenovirus-mediated gene transfer succeeded in gene expression in the kidney. Adeno-associated virus has a potential to be utilized as a vector targeting both kidney and skeletal muscle. Given that the systemic delivery of the functional protein can serve for the therapy of the renal diseases, skeletal muscle targeting gene therapy might be an alternative strategy for treatment of renal disease. Non-viral vectors such as the haemagglutinating virus of Japan (HVJ)-liposome method and cationic liposome are possibilities, but their efficiency needs to be improved. Electric pulse is emerging as a new and less harmful strategy of gene transfer to various tissues, including the kidney. I believe that two plausible strategies exist for the therapeutic use of gene transfer in the near future: skeletal muscle-targeting gene therapy and kidney transplantation. Application of gene therapy to the transplanted kidney may potentially improve graft outcome by reducing acute and chronic rejections. The emerging strategies of gene transfer in kidneys are reviewed and the potential application of gene therapy in renal diseases are discussed.