Comparative Impact of Isolated Ultrafiltration and Hemodialysis on Fluid Distribution: A Bioimpedance Study.

INTRODUCTION: Isolated ultrafiltration (IUF) is an alternative treatment for diuretic-resistant patients with fluid retention. Although hemodialysis (HD) predominantly decreases extracellular water (ECW), the impact of IUF on fluid distribution compared with HD remains unclear. METHODS: We compared the effect of HD (n = 22) and IUF (n = 10) sessions on the body fluid status using a bioimpedance analysis device (InBody S10). RESULTS: The total ultrafiltration volume was similar between HD and IUF (HD 2.5 ± 0.3 vs. ICF 2.1 ± 0.3 L/session, p = 0.196). The reduction rate of ECW was significantly higher than that of intracellular water (ICW) after HD (ECW -7.9% ± 0.8% vs. ICW -3.0% ± 0.9%, p < 0.001) and IUF (ECW -5.8% ± 0.9% vs. ICW -3.6% ± 0.8%, p = 0.048). However, the change in the ratio of ECW to total body water in HD was significantly larger than that in IUF (HD -3.2% ± 0.3% vs. ICF -1.1% ± 0.4%, p < 0.001). The reduction rates in serum tonicity (effective osmolality) were higher after HD than after IUF (HD -1.8% ± 0.5% vs. IUF -0.6% ± 0.2%, p = 0.052). Among the components of effective osmolality, the reduction rates of serum K+ and glucose levels after HD were significantly higher than those after IUF (serum K+: HD -30.5% ± 1.6% vs. IUF -0.5% ± 3.8%, p < 0.001; serum glucose: HD -15.4% ± 5.0% vs. IUF 0.7% ± 4.8%, p = 0.026), while the serum Na+ level was slightly and similarly reduced (HD -0.8% ± 0.4% vs. IUF -0.8% ± 0.4%, p = 0.500). The reduction in the osmolal gap value (measured osmolality-calculated osmolarity) was significantly greater after HD sessions than after IUF sessions (HD -12.4 ± 1.4 vs. IUF 2.0 ± 1.0 mOsm/kg, p = 0.001). CONCLUSION: The extracellular fluid reduction effect of HD is stronger than that of IUF. The different changes in effective osmolality and osmolal gap after HD and IUF sessions may be related to the different effects of HD and IUF on fluid distribution.

Effects of the sodium-glucose cotransporter 2 inhibitor dapagliflozin on fluid distribution: A comparison study with furosemide and tolvaptan.

AIM: Sodium-glucose cotransporter 2 (SGLT2) inhibitors are an antihyperglycemic drug with diuretic properties. We recently reported that an SGLT2 inhibitor ameliorated extracellular fluid expansion with a transient increase in urinary Na+ excretion. However, the effects of SGLT2 inhibitors on fluid distribution in comparison to conventional diuretics remain unclear. METHODS: Forty chronic kidney disease patients with fluid retention (average estimated glomerular filtration rate 29.2 ± 3.2 mL/min per 1.73 m2 ) were divided into the SGLT2 inhibitor dapagliflozin (DAPA), loop diuretic furosemide (FR) and vasopressin V2 receptor antagonist tolvaptan (TLV). The body fluid volume was measured on days 0 and 7 using a bioimpedance analysis device. RESULTS: In all three groups, body weight was significantly and similarly decreased, and urine volume numerically increased for 7 days. Bioimpedance analysis showed that the changes in intracellular water were similar, but that there were significant changes in the extracellular water (ECW) (DAPA -8.4 ± 1.7, FR -12.5 ± 1.3, TLV -7.4 ± 1.5%, P = 0.048). As a result, the change in the ratio of ECW to total body water in the DAPA group was significantly smaller than that in the FR group, but numerically larger than that in the TLV group (DAPA -1.5 ± 0.5, FR -3.6 ± 0.5, TLV -0.5 ± 0.4%, P < 0.001). CONCLUSION: Sodium-glucose cotransporter 2 inhibitor DAPA predominantly decreased the ECW with a mild increase in urine volume, but the change in the ECW/total body water was smaller than that in patients treated with FR, and larger than that in patients treated with TLV, suggesting that the effects of SGLT2 inhibitors on fluid distribution may differ from those of conventional diuretics.

The impact of preserved Klotho gene expression on antioxidative stress activity in healthy kidney.

Klotho, which was originally identified as an antiaging gene, forms a complex with fibroblast growth factor 23 receptor in the kidney, with subsequent signaling that regulates mineral metabolism. Other biological activities of Klotho, including antiaging effects such as protection from various types of cellular stress, have been shown; however, the precise mechanism of these effects of Klotho gene in the healthy human kidney is not well understood. In this study, we examined the relationships of Klotho and antioxidative stress gene expression levels in zero-hour biopsy specimens from 44 donors in kidney transplantation and verified them in animal models whose Klotho gene expression levels were varied. The nitrotyrosine expression level in the kidney was evaluated in these animal models. Expression levels of Klotho gene were positively correlated with the p53 gene and antioxidant enzyme genes such as catalase, superoxide dismutase 1 (SOD1), SOD2, peroxiredoxin 3 (PRDX3), and glutathione peroxidase 1 (GPX1) but not clinical parameters such as age and renal function or pathological features such as glomerulosclerosis and interstitial fibrosis tubular atrophy. The expression levels of all genes were significantly higher in mice with Klotho overexpression than in wild-type mice, and those except for catalase, PRDX3, and GPX1 were significantly lower in Klotho-deficient mice than in wild-type littermate mice. Nitrotyrosine-positive bands of various sizes were observed in kidney from Klotho-deficient mice only. The preservation of Klotho gene expression might induce the antioxidative stress mechanism for homeostasis of healthy human kidney independently of its general condition, including age, renal function, and histological findings.

The association between soluble intercellular adhesion molecule-1 levels in drained dialysate and peritoneal injury in peritoneal dialysis.

BACKGROUND: Chronic inflammation of the peritoneum causes peritoneal injury in patients on peritoneal dialysis. Intercellular adhesion molecule-1 and its circulating form, soluble intercellular adhesion molecule-1, play pivotal roles in inflammation. However, their role in peritoneal injury is unclear. METHODS: We measured changes in intercellular adhesion molecule-1 expression in the peritoneum of a peritoneal injury model in rats. The associations between soluble intercellular adhesion molecule-1 levels in drained dialysate and the solute transport rate (D/P-Cr and D/D0-glucose) determined by the peritoneal equilibration test, and matrix metalloproteinase-2 levels in drained dialysate were investigated in 94 peritoneal drained dialysate samples. RESULTS: Intercellular adhesion molecule-1 expression was increased in the peritoneum of rats with peritoneal injury. Soluble intercellular adhesion molecule-1 levels in drained dialysate were significantly positively correlated with D/P-Cr (r = .51, p < .01) and inversely correlated with D/D0-glucose (r = -.44, p < .01). They were also significantly positively correlated with matrix metalloproteinase-2 levels in drained dialysate (r = .86, p < .01). CONCLUSIONS: Intercellular adhesion molecule-1expression is increased in the peritoneum of a peritoneal injury model in the rat, and soluble intercellular adhesion molecule-1 levels in drained dialysate are associated with peritoneal injury in patients on peritoneal dialysis. These results suggest that soluble intercellular adhesion molecule-1 could be a novel biomarker of peritoneal injury in patients on peritoneal dialysis.

Prevalence of Fabry disease in dialysis patients: Japan Fabry disease screening study (J-FAST).

BACKGROUND: In Fabry disease, progressive glycolipid accumulation leads to damage in kidney and other organs. This study was designed to determine the prevalence rate of Fabry disease in Japanese dialysis patients. METHODS: All dialysis patients agreeing to Japan Fabry disease screening study (J-FAST) with informed consent were selected except for Fabry disease. The screening was performed by a method of measuring plasma and/or leukocytes lysosomal α-galactosidase A protein level and α-galactosidase A activity. If positive, genetic analysis was carried out upon patient's agreement. RESULTS: J-FAST dealt with 8547 patients (male 5408, female 3139). At the tertiary examination, 26 out of 8547 patients were found to be positive. Six out of 26 patients could not accept genetic analysis because of death. Remaining 20 patients agreed with genetic analysis; then 2 patients (male 2, female 0) had a variation of the α-Gal gene and 11 patients showed E66Q variations. Therefore, the frequency of Fabry disease in J-FAST was 0.04 % (2/5408) in males and 0 % (0/3139) in females, and then 0.02 % (2/8547) in all patients. The presumptive clinical diagnoses of end-stage kidney disease (ESKD) were 10 chronic glomerulonephritis, 7 diabetic nephropathy, 3 unknown etiology, 3 nephrosclerosis, 1 gouty nephropathy, 1 autosomal dominant polycystic kidney disease and 1 renal tuberculosis among 26 tertiary positive patients. Two male Fabry patients were initially diagnosed as nephrosclerosis and chronic glomerulonephritis. CONCLUSIONS: The prevalence rate of Fabry disease in J-FAST was 0.02 %. Moreover, Fabry disease could not be ruled out as the clinical diagnosis of ESKD.

Subclinical growth of an arteriovenous fistula associated with renal biopsy: a case report.

BACKGROUND: Renal biopsy is not free from complications and patients who undergo this procedure are usually hospitalized to receive intensive care for several days after biopsy. In contrast, after this period, routine follow-up to detect biopsy-associated complications is rarely scheduled, unless the patient develops a clinical manifestation. We describe a case of marked enlargement of arteriovenous fistula in the kidney that occurred many years after renal biopsy. In contrast to the previous cases requiring interventional radiology, our patient showed subclinical growth of fistula over about nine years. CASE PRESENTATION: A 24-year-old man with a history of percutaneous renal biopsy was hospitalized for interventional radiology. Gross hematuria emerged shortly after biopsy, but completely disappeared with administration of hemostatic agents and bed rest. Subsequently, the patient had few symptoms for many years. A giant fistula (a gourd-shaped mass, size 26 × 22 and 12 × 11 mm) was unexpectedly detected by ultrasonography performed for examination of an unrelated disorder (slight elevation of serum transaminase) at 9 years after the original biopsy. The fistula was successfully treated with radiological intervention. Thus, subclinical development of complications associated with renal biopsy should be considered, even in an uneventful course. CONCLUSIONS: This case provides a platform to discuss the importance of long-term follow-up of patients after renal biopsy despite of its difficulty.

Attenuation of methylglyoxal-induced peritoneal fibrosis: immunomodulation by interleukin-10.

Peritoneal fibrosis (PF), a serious pathophysiology of peritoneal dialysis (PD), is implicated in various types of chronic inflammation. In the present study, we examined the benefits of interleukin (IL)-10, which exerts anti-inflammatory effects, in an experimental rat model of methylglyoxal (MGO)-induced PF. We injected an adeno-associated virus (AAV) vector encoding rat IL-10 or enhanced green fluorescent protein (GFP) into male Sprague-Dawley rats at 6 weeks of age. Four weeks later, the rats received continuous peritoneal injections of conventional PD fluid (PDF) with MGO for 3 weeks. Then, the peritoneal histology and the expression levels of fibrogenic mediators and proinflammatory cytokines were analyzed. The rats demonstrating persistent IL-10 expression showed significantly reduced fibrous peritoneal thickening compared with those with GFP expression. The infiltration of macrophages, the expression of tumor necrosis factor-α, IL-1ß, IL-6, transforming growth factor-ß1, Snail, and matrix metalloproteinase 2 genes as well as the proliferation of mesenchymal-like mesothelial cells augmented by MGO were all significantly suppressed by IL-10 expression. IL-10 also abrogated the extent of MGO-induced bowel adhesions mimicking a cocoon-like mass. Our findings provide valuable insight into the potential benefit of immunomodulation with IL-10 as one potentially effective therapeutic strategy for preventing the onset of peritoneal injury resulting in PF.

[Comparison of benefits to non-dialysis CKD patients between darbepoetin alpha and epoetin beta pegol].

BACKGROUND: Erythropoiesis-stimulating agents (ESAs) are the mainstay of treatment for renal anemia in chronic kidney disease (CKD) patients. However, the difference in hematopoietic effect between darbepoetin alfa (DA) and continuous erythropoiesis receptor activator (CERA) has remained unclear in non-dialysis CKD patients. Another purpose of this study was to analyze the red blood cells indices under treatment with these two ESAs in ESA-naïve CKD patients. METHODS: This study was designed as a multicenter retrospective observational investigation, and included 61 patients receiving DA (group DA) and 36 patients receiving CERA (group CERA) for at least six months. Relative effect of these ESAs was determined by comparing means of the individual monthly average of the area under the curve above the initial level of hemoglobin (Hb), hematocrit (Hct), and red blood cell count (RBC) with the trapezoidal rule, which are maintenance ratios. Serial changes in mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were also evaluated. RESULTS: No differences were found in the mean ratios of Hb, Hct, and RBC, and maintenance ratios of these parameters. The ratio of MCH in group CERA was decreased compared with that in group DA. Subsequent decrease in MCV was also remarkable in group CERA. CONCLUSIONS: It is speculated that iron demand increased during the administration of CERA, which was suggested by changes in the red cell indices. Reticulocyte indices and iron-related parameters could provide a more detailed explanation and the significance of iron supplementation during administration of CERA should be clarified when compared with other types of ESA.

Peritoneal fibrosis induced by intraperitoneal methylglyoxal injection: the role of concurrent renal dysfunction.

BACKGROUND: Peritoneal fibrosis (PF) is a serious pathophysiology of peritoneal dialysis (PD). An ongoing focus of research is the potential fibrogenic nature of methylglyoxal (MGO) in conventional PD fluid (PDF). The aim of the current study was to explore the effects of the uremic milieu on the promotion of PF by MGO using rats with adenine-induced renal failure (RF). METHODS: Adenine-treated Sprague-Dawley rats were randomly assigned to receive continuous peritoneal injections of PDF with or without MGO for three weeks or were left untreated for the same duration. Rats without RF were also assigned to three groups. The peritoneal histology and expression levels of type I collagen, transforming growth factor-ß1 (TGF-ß1), α-smooth muscle actin (αSMA), Snail, matrix metalloproteinase-2 (MMP-2), advanced glycation end-products (AGEs) and the receptor for AGE (RAGE) were then analyzed. RESULTS: Peritoneal treatment with 5 mM MGO accelerated the fibrous peritoneal thickening progression promoted by exposure to standard PDF in the rats with RF, but not in the rats with a normal renal function. Treatment with MGO significantly augmented the proliferation of mesenchymal-like mesothelial cells, accumulation of AGE, de novo expression of αSMA and RAGE and gene expression of type I collagen, TGF-ß1, Snail and MMP-2, whereas both MGO and RF alone had, at most, marginal effects on the changes in these biological parameters. CONCLUSIONS: In the present study, the adverse effects of MGO on the peritoneum became more prominent under conditions of a uremic milieu. These findings imply that MGO and uremia act cooperatively to induce PF.

Fabry disease: experience of screening dialysis patients for Fabry disease.

The prevalence rate for Fabry disease is conventionally considered to be 1 case in 40,000; however, due to increased screening accuracy, reports now suggest that prevalence is 1 case in 1,500 among male children, and it is likely that the clinical importance of the condition will increase in the future. In dialysis patients to date, prevalence rates are between 0.16 and 1.2 %. Globotriaosylsphingosine (Lyso-GL-3), which is a substrate of α-galactosidase A (α-Gal A), has surfaced as a new biomarker, and is also effective in the determination and monitoring of the effects of enzyme replacement therapy. In terms of genetic abnormalities, the E66Q mutation has recently become a topic of discussion, and although doubts have been expressed over whether or not it is the gene responsible for Fabry disease, there is still a strong possibility that it is a functional genetic polymorphism. At present, the standard treatment for Fabry disease is enzyme replacement therapy, and in order to overcome the problems involved with this, a method of producing recombinant human α-Gal A using methanol-assimilating yeast, and chemical or medicinal chaperone treatment are of current interest. Migalastat hydrochloride is known as a pharmacological chaperone, but is currently in Phase III global clinical trials. Adding saposin B to modified α-N-acetyl galactosaminidase is also under consideration as a treatment method.

A case of paraneoplastic IgA nephropathy with glomerular capillary IgA and galactose-deficient IgA1 deposition.

Paraneoplastic IgA nephropathy (IgAN) is an underrecognized condition in which malignancy manifests as symptoms of IgAN, and it remains controversial regarding their mechanistic relation between IgAN and malignancy. Herein, we report a case of a 68-year-old Japanese man with glottic cancer who developed nephrotic syndrome as a clinical manifestation of IgAN. Renal biopsy revealed diffuse proliferative glomerulonephritis with glomerular capillary IgA deposition that is a rare subtype of IgAN. After complete remission of the glottic cancer by irradiation, proteinuria and hematuria disappeared. Based on his clinical course, we diagnosed paraneoplastic IgAN. Therefore, we should consider the possibility that IgAN with glomerular capillary IgA deposition might be paraneoplastic glomerulopathy especially before initiating immunosuppressive therapy. The patient thereafter developed prostate cancer and hepatocellular cancer, but IgAN did not recur. The association of IgAN specifically with the glottic cancer in this triple-cancer patient may suggest a potential link between IgAN and mucosal cancer. Because galactose-deficient IgA1 (Gd-IgA1) was observed in the similar pattern as IgA, Gd-IgA1 also may play an important role in the pathogenesis of paraneoplastic IgAN.

Sodium-Glucose Cotransporter 2 Inhibitor Combined with Conventional Diuretics Ameliorate Body Fluid Retention without Excessive Plasma Volume Reduction.

We previously reported that sodium-glucose cotransporter 2 (SGLT2) inhibitors exert sustained fluid homeostatic actions through compensatory increases in osmotic diuresis-induced vasopressin secretion and fluid intake. However, SGLT2 inhibitors alone do not produce durable amelioration of fluid retention. In this study, we examined the comparative effects of the SGLT2 inhibitor dapagliflozin (SGLT2i group, n = 53) and the combined use of dapagliflozin and conventional diuretics, including loop diuretics and/or thiazides (SGLT2i + diuretic group, n = 23), on serum copeptin, a stable, sensitive, and simple surrogate marker of vasopressin release and body fluid status. After six months of treatment, the change in copeptin was significantly lower in the SGLT2i + diuretic group than in the SGLT2i group (-1.4 ± 31.5% vs. 31.5 ± 56.3%, p = 0.0153). The change in the estimated plasma volume calculated using the Strauss formula was not significantly different between the two groups. Contrastingly, changes in interstitial fluid, extracellular water, intracellular water, and total body water were significantly lower in the SGLT2i + diuretic group than in the SGLT2i group. Changes in renin, aldosterone, and absolute epinephrine levels were not significantly different between the two groups. In conclusion, the combined use of the SGLT2 inhibitor dapagliflozin and conventional diuretics inhibited the increase in copeptin levels and remarkably ameliorated fluid retention without excessively reducing plasma volume and activating the renin-angiotensin-aldosterone and sympathetic nervous systems.

Severe acute interstitial nephritis induced by α-glucosidase inhibitor miglitol in an elderly patient with type 2 diabetic nephropathy.

A 79-year-old male patient with type 2 diabetic nephropathy and hypertension was admitted to our hospital because of acute kidney injury with significantly elevated serum creatinine (8.12 mg/dL) and urinary ß2-microglobulin (ß2MG, 31,748 µg/L) levels. α-Glucosidase inhibitor (α-GI) miglitol, started two weeks prior to presentation, was discontinued because drug-induced acute interstitial nephritis (AIN) was suspected. Renal biopsy revealed AIN and diabetic nephropathy. The drug-induced lymphocyte stimulation test for miglitol was also positive. After the discontinuation of miglitol, the urinary ß2MG levels decreased to the normal range. This case raises the possibility that α-GI miglitol can worsen the renal function in patients with underlying renal dysfunction.

Acute Interstitial Nephritis with Glomerular Capillary IgA Deposition Following SARS-CoV-2 mRNA Vaccination.

We herein report a case of acute kidney injury (AKI) presenting as acute interstitial nephritis (AIN) after the first dose of the BNT162b2 mRNA vaccine against coronavirus disease 2019 (COVID-19). A 69-year-old man with a history of diabetes and hypertension presented with AKI 4 days after receiving the vaccine. Despite the administration of methylprednisolone pulse treatment, his renal function worsened, which prompted us to initiate temporal hemodialysis. His renal function subsequently improved, and a renal biopsy confirmed AIN and glomerular capillary IgA deposition without apparent crescents. The clinical history and histological findings suggest a relationship between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination and AIN as a rare side effect.

Fluid homeostatic action of dapagliflozin in patients with chronic kidney disease: the DAPA-BODY Trial.

Sodium glucose cotransporter 2 (SGLT2) inhibitors have both glucose-lowering and diuretic effects. We recently reported that the SGLT2 inhibitor dapagliflozin exerts short-term fluid homeostatic action in patients with chronic kidney disease (CKD). However, the long-term effects of SGLT2 inhibitors on body fluid status in patients with CKD remain unclear. This was a prospective, non-randomized, open-label study that included a dapagliflozin treatment group (n = 73) and a control group (n = 24) who were followed for 6 months. Body fluid volume was measured using a bioimpedance analysis device. The extracellular water-to-total body water ratio (ECW/TBW), a predictor of renal outcomes, was used as a parameter for body fluid status (fluid retention, 0.400 ≤ ECW/TBW). Six-month treatment with dapagliflozin significantly decreased ECW/TBW compared with the control group (-0.65% ± 2.03% vs. 0.97% ± 2.49%, p = 0.0018). Furthermore, dapagliflozin decreased the ECW/TBW in patients with baseline fluid retention, but not in patients without baseline fluid retention (-1.47% ± 1.93% vs. -0.01% ± 1.88%, p = 0.0017). Vasopressin surrogate marker copeptin levels were similar between the control and dapagliflozin groups at 6 months (32.3 ± 33.4 vs. 30.6 ± 30.1 pmol/L, p = 0.8227). However, dapagliflozin significantly increased the change in copeptin levels at 1 week (39.0% ± 41.6%, p = 0.0010), suggesting a compensatory increase in vasopressin secretion to prevent hypovolemia. Renin and aldosterone levels were similar between the control and dapagliflozin groups at 6 months, while epinephrine and norepinephrine (markers of sympathetic nervous system activity) were significantly lower in the dapagliflozin group than in the control group. In conclusion, the SGLT2 inhibitor dapagliflozin ameliorated fluid retention and maintained euvolemic fluid status in patients with CKD, suggesting that SGLT2 inhibitors exert sustained fluid homeostatic actions in patients with various fluid backgrounds. Clinical trial registration: https://www.umin.ac.jp/ctr/, identifier [UMIN000048568].

Development of features of glomerulopathy in tumor-bearing rats: a potential model for paraneoplastic glomerulopathy.

BACKGROUND: It has been well-recognized that cancer patients occasionally develop renal disorders independently of direct tumor invasion. However, the clinical entity of paraneoplastic glomerulopathy remains poorly understood, in part due to the lack of an animal model for basic research. In the present study, we investigated whether cancer-bearing rats develop features of glomerulopathy. METHODS: RCN-9 rat colon cancer cells (1 × 10(7)) were injected into F344 rats (n = 13) and T cell-deficient F344 rats (nude rats; n = 7) via the portal system. Urinalysis and histological examinations were performed in comparison with control rats (n = 6) that received a vehicle injection. RESULTS: Metastatic growth of RCN-9 cells exclusively in the liver was observed in the cancer-injected F344 rats, whereas direct invasion into the kidney was not evident even microscopically. Two of the cancer-injected F344 rats died within 2 days, but 9 of the 11 that avoided early death showed elevation of urinary protein (up to 158.0 mg/day) compared to controls (mean values: 60.8 ± 12.9 versus 17.8 ± 2.1 mg/day, P = 0.0291). Although morphological changes were not evident in light microscopy, abundant IgG in the glomerular tufts of the proteinuric rats was shown immunohistochemically. Ultrastructure analysis revealed electron-dense deposits in the glomerular basement membrane zone and effacement of the podocytic foot process. Interestingly, none of the nude rats showed proteinuria despite of cancer growth, suggesting that a specific immune response was involved. CONCLUSIONS: The tumor-bearing rats developed features of glomerulopathy, as expected from the clinical perspective, and this animal model may provide new insights into the development of paraneoplastic glomerulopathies.

Matrix metalloproteinase-2 inhibition by temocapril and its important role in peritoneal transport.

1. Matrix metalloproteinase (MMP)-2 plays an important role in tissue remodelling during peritoneal injury caused by peritoneal dialysis (PD), but MMP-2 inhibitors have not yet been used clinically. Recently, it was reported that captopril, an angiotensin-converting enzyme inhibitor (ACEI), can inhibit MMP-2. 2. To investigate the potential usefulness of ACEI during PD, the molecular interaction between the MMP-2 active site and the active form of temocapril (temocaprilat) was investigated using molecular modelling. Furthermore, the effects of temocapril on MMP-2 activity in peritoneal effluents and the peritoneal solute transport rate of PD patients were determined. 3. Temocaprilat bound to the MMP-2 active centre and recognized two hydrophobic substrate-binding sites in the MMP-2 molecular model. Matrix metalloproteinase-2 activity in peritoneal effluents was directly inhibited by temocaprilat (IC(50) 0.47 µmol/L). In one patient given temocapril, the peritoneal solute transport rate decreased gradually during PD. 4. Temocapril may prove to be an important candidate for development as a novel therapeutic agent for MMP-2 inhibition to prevent peritoneal injury caused by PD.

Accelerated recovery from nephrotic syndrome with acute renal failure by double filtration plasmapheresis in a patient with lupus podocytopathy.

We describe a case of an adult female who presented with nephrotic syndrome. She was diagnosed with systemic lupus erythematosus with serum antinuclear antibodies, leucopenia with lymphopenia, butterfly erythema, and nephrotic syndrome. Renal biopsy revealed normal glomeruli with diffuse effacement of the foot processes, consistent with lupus podocytopathy. Although human albumin replacement was performed initially, acute renal failure developed rapidly. Therefore, she was treated with double filtration plasmapheresis (DFPP) in addition to oral steroid. After steroid therapy combined with DFPP, the renal function and proteinuria improved rapidly. Although the impact of DFPP on the treatment of lupus nephritis remains to be delineated, our observations suggest that DFPP in lupus podocytopathy played a pivotal role in facilitating the early recovery from renal injuries. Because of the rapid improvement of renal function without any change in body weight by DFPP, acute renal failure in the setting of lupus podocytopathy might contribute to an alternative pathophysiological factor for the diminished glomerular filtration rate, similar to that observed in the setting of idiopathic minimal change glomerulopathy.

Comparison between serum free triiodothyronine levels and body fluid distribution in hemodialysis patients.

AIM: Low free triiodothyronine (fT3) has been associated with the presence of malnutrition-inflammation syndrome in patients with end-stage renal disease (ESRD) and decreased overall survival in ESRD. Since thyroid hormone has a particular effect on body fluid status, we hypothesized that hemodialysis patients with low-T3 syndrome might have interstitial edema. In this study, we examined the relationship between levels of thyroid hormone and body composition parameters in Japanese hemodialysis patients. METHODS: The subjects were 52 patients on maintenance hemodialysis. Serum levels of thyroid hormone and atrial natriuretic peptide (hANP) were measured. Body composition parameters were measured using a bioimpedance body composition analyzer. RESULTS: Serum fT3 had positive correlations with body mass index (BMI), body fat mass (BFM), total body water (TBW) and intracellular water (ICW), and negative correlations with the ratio of extracellular water to total body water (ECW/TBW) and hANP. There were no correlations between serum fT4 and any body composition parameter. The 49 patients with data at baseline and after 1 year were divided into groups with increased (n = 33) and decreased (n = 16) fT3 after 1 year. ΔBMI and ΔBFM were significantly lower and ΔTBW, ΔICW, ΔECW and ΔECW/TBW (changes over 1 year from baseline) were significantly higher in patients with decreased fT3 compared to those with increased fT3. There was no significant difference in ΔhANP or Δcardiothoracic ratio between the two groups. CONCLUSION: These results show that a decrease in fT3 might be associated with emaciation and interstitial edema in Japanese hemodialysis patients.

The relationship between the soluble Klotho protein and the residual renal function among peritoneal dialysis patients.

BACKGROUND: Klotho has been investigated as an anti-aging protein that is predominantly expressed in the distal convoluted tubules in the kidneys and in the choroid plexus of the brain. The purpose of the present study was to determine the relationship between the soluble form of Klotho and renal function in chronic peritoneal dialysis (PD) patients, a relationship which remains poorly understood. METHODS: The soluble Klotho levels in the serum, urine, and peritoneal dialysate obtained from thirty-six PD patients were determined by a sandwich enzyme-linked immunosorbent assay system. RESULTS: The amount of urinary excreted soluble Klotho over 24 h ranged from 1.54 to 1774.4 ng/day (median 303.2 ng/day; interquartile range [IR] 84.1-498.5), while the serum soluble Klotho concentration ranged from 194.4 to 990.4 pg/ml (mean 553.7 ± 210.4 pg/ml). The amount of urinary Klotho excretion was significantly correlated with residual renal function. However, there was no apparent correlation between the serum soluble Klotho levels and the residual renal function. Klotho was also detected in the 24-h dialysate collections. There was a significant correlation between the peritoneal Klotho excretion and the amount of albumin contained in the dialysate collections (r = 0.798, p < 0.01). CONCLUSIONS: The total amount of urinary excreted Klotho, but not the serum level of soluble Klotho, may be a potential biomarker for assessing the residual renal function among PD patients. Whether our findings are also valid for chronic kidney disease patients overall should therefore be evaluated in greater detail.