糸球体硬化症モデルにおけるメサンギウム浄化機構に関する研究: ダウノマイシン投与ラットのメサンギウム異物処理機構の障害とアンギオテンシン変換酵素阻害剤によるその改善効果について

取得学位 : 博士（医学）, 学位授与番号 : 医博甲第943号, 学位授与年月日：平成2年3月25日,学位授与年：199

A proximal direct repeat motif characterized as a negative regulatory element in the human renin gene

The regulation of renin gene expression is thought to be fundamental to regulation of the total renin-angiotensin system. The human renin gene contains a direct repeat (DR) motifAGGGGTCAC-AGGGCCA in the proximal region (-259/-245 bp), which contains similar sequence for nuclear receptor superfamily binding core motif, AGGTCA, and is the most similar to COUP-TFII consensus. The DR motif was evaluated as a functional cis-element with renal cortex and chorio-decidual cells by footprint assay, electromobility shift assay (EMSA) and reporter assay. The DR motif site was protected by footprint analysis with a clear hypersensitive and a minor hypersensitive region in good accordance with the DR of the consensus. One of the binding proteins was strongly suspected to be COUP-TFII-consensus-specific by EMSA. The DNA/protein complexes obtained with nuclear extract of renin producing cells could be completely blocked by homologous competitor and strongly blocked by the second-half mutant oligonucleotide of the DR motif but not by the first-half mutant oligonucleotide. Finally, the transcriptional activity of second-half mutant construct is slightly elevated and that first-half mutant construct is significantly stronger by twofold compared with wild type construct in reporter assay. These findings suggest that the DR motif site of the human renin gene functions as a negative regulatory element involved in a twofold repression of transcription and that member(s) of nucleic receptor superfamily bind the site and play important roles in the human renin gene expression with a possibility that one of the binding protein is COUP-TFII

Hints to the diagnosis of uromodulin kidney disease.

Background: Uromodulin kidney disease (UKD) is an inherited kidney disease caused by a uromodulin (UMOD) gene mutation. The UMOD gene encodes the Tamm-Horsfall protein (THP), which is the most abundant protein in healthy human urine. Because of its rarity, the incidence of UKD has not been fully elucidated. The purpose of the present study is to clarify the frequency of UKD among patients who underwent renal biopsy. Methods: Immunostaining for THP was performed for patients <50 years of age with renal insufficiency and hyperuricemia without overt urinalysis abnormality from renal biopsy databases. Serum and urinary THP concentrations were evaluated in available individuals. Results: Fifteen patients were selected for immunostaining from a total of 3787 patients. In three independent patients, abnormal THP accumulation in renal tubular cells was observed. A novel missense A247P UMOD mutation was detected in two of the three patients, including one having a typical family history of familial juvenile hyperuricemic nephropathy. Serum and urinary THP concentrations of all available patients withUMODA247P mutationwere significantly lower than those of controls. Conclusions: In the present study, UKDwas detected in <1 in 1000 subjects who underwent renal biopsies. However, in subjects meeting all of the above criteria, abnormal THP accumulation was detected in 20% (3/15), suggesting that renal biopsy with immunostaining for THP is a good tool for diagnosing UKD. Also, lowserum THP concentration detected in the present subjects might be a good diagnostic marker or important in understanding the pathogenesis of UKD. © The Author 2015.Publisher\u27s version/PDF on institutional repository or centrally organised repositorie

A crossover comparison of urinary albumin excretion as a new surrogate marker for cardiovascular disease among 4 types of calcium channel blockers

Background: At the intervention for cardiovascular disease (CVD), albuminuria is a new pivotal target. Calcium channel blocker (CCB) is one of the most expected agents. Currently CCBs have been classified by delivery system, half-life and channel types. We tested anti-albuminuric effect among 4 types of CCBs. Methods: Subjects were 50 hypertensives (SBP/DBP 164.7 ± 17.1/92.3 ± 12.2 mm Hg, s-Cr 0.81 ± 0.37 mg/dl, urinary albumin excretion (UAE) 69.4 (33.5-142.6) mg/gCr). Four CCBs were administered in a crossover setting: nifedipine CR, a long biological half-life L type by controlled release; cilnidipine, an N/L type; efonidipine, a T/L type; and amlodipine, a long biological half-life L type. Results: Comparable BP reductions were obtained. UAE at endpoints ware as follows (mg/gCr,*P < 0.01): nifedipine CR 30.8 (17.3-81.1),* cilnidipine 33.9 (18.0-67.7),* efonidipine 51.0 (21.2-129.8), amlodipine 40.6 (18.7-94.7). By all agents, significant augmentations were observed in PRA, angiotensin I and angiotensin II (AngII). AngII at cilnidipine was significantly lower than that at amlodipine. PAC at cilnidipine and efonidipine was significantly lower than that at amlodipine. Nifedipine CR significantly reduced ANP concentration. Conclusions: It is revealed that only nifedipine CR and cilnidipine could reduce albuminuria statistically. Thus, it is suggested that the 2 CCBs might be favorable for organ protection in hypertensives. © 2011 Elsevier Ireland Ltd

Situs inversus and cystic kidney disease: Two adult patients with this heterogeneous syndrome

Background: Situs inversus is a rare complication of cystic kidney diseases. Only three genes, INVS (NPHP2), NPHP3 and PKD2 have been proved to be responsible for some cases, while the responsible genes in many others are still unknown. Case Reports: Here we report two male patients with situs inversus combined with cystic kidney disease without any family history of polycystic kidney disease. Their renal function was normal in childhood but culminated in end stage renal disease in middle age. No pathogenic mutations were found in mutation analysis of INVS, IFT88, PKD2, UMOD or NPHP3 in them. Conclusions: Past reported cases of situs inversus and cystic kidney diseases were divided into three groups, i.e., gestational lethal renal dysplasia group, infantile or juvenile nephronophthisis group and polycystic kidney disease group. The present patients are different from each of these groups. Moreover, the renal lesions of the present two cases are quite different from each other, with one showing mildly atrophic kidneys with small numbers of cysts and the other an enlarged polycystic kidney disease, suggesting very heterogeneous entities

Tissue Gene Expression of Renin-Angiotensin System in Human Type 2 Diabetic Nephropathy

OBJECTIVE—Recent studies have proved that blockade of the renin-angiotensin system (RAS) retards the progression of diabetic nephropathy, whereas hyporeninemia is known as a typical state in diabetic subjects. The purpose of this study is to determine whether expression levels of RAS differ between nondiabetic and diabetic renal tissues with accurate quantitative method. RESEARCH DESIGN AND METHODS—Subjects were 66 nondiabetic and 8 diabetic patients with biopsy-proven renal diseases. The eight diabetic subjects suffered from type 2 diabetes with overt proteinuria. Renal histology revealed typical diffuse or nodular lesions with linear IgG deposit on immunofluorescent staining and thickened basement membrane on electronic microscopy. Total RNA from a small part of the renal cortical biopsy specimens was reverse-transcribed, and the resultant cDNA was amplified for new major components of RAS (i.e., renin, renin receptor, angiotensinogen, ACE, ACE2, angiotensin II type 1 receptor, and angiotensin II type 2 receptor) and measured. RESULTS—Among these components, a significant upregulation was observed in the ACE gene in diabetic renal tissue. CONCLUSIONS—The results suggest that renal tissue RAS might be activated in the respect that ACE gene expression is upregulated in spite of a tendency to low renin expression in type 2 diabetic nephropathy

On the top of ARB N/L type Ca channel blocker leads to less elevation of aldosterone

Synopsis The activation of the renin-angiotensin system (RAS) is one of the unfavourable characteristics of calcium channel blocker (CCB). N type calcium channel is thought to be involved in renin gene transcription and adrenal aldosterone release. Accordingly, N/L type CCB has a possibility of less elevation of plasma aldosterone concentrations (PAC) among CCBs. In a monotherapy study, we had already demonstrated that N/L type CCB leads to less activation of the RAS compared with L type CCB. The objective of this study is to substantiate the hypothesis that at the condition of additive administration on the top of an angiotensin receptor blocker (ARB), still N/L type CCB leads to less elevation of PAC compared with L type one. Subjects were 60 hypertensives administered with valsartan. As an open label study, amlodipine (L type) or cilnidipine (N/L type) were administered on the top of valsartan (ARB) in a cross-over manner. Results were as follows (valsartan + amlodipine compared with valsartan + cilnidipine): systolic blood pressure (SBP)/diastolic blood pressure (DBP) (mmHg): 132 + − 10/76 + − 10 compared with 131 + − 10/77 + − 9, P = 0.95/0.48, plasma renin activity (PRA) (ng/ml·h): 2.41 + − 2.67 compared with 2.00 + − 1.50 P = 0.20, PAC (pg/ml): 77.3 + − 31.0 compared with 67.4 + − 24.8, P &lt; 0.05, urinary albumin excretion (UAE) (mg/gCr): 105.9 + − 216.1 compared with 73.9 + − 122.2, P &lt; 0.05. Thus, PAC at cilnidipine was significantly lower than those at amlodipine in spite of the comparable BP reductions. Besides, UAE was significantly lower at cilnidipine. In conclusion, on the top of the ARB, it is suggested that cilnidipine administration might lead to less elevation of PAC and reduction in UAE compared with amlodipine