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D Matsuo

Publications and source records attributed to D Matsuo.

6 recordsLinked to original sources
PubMed2006

Persistent hyperparathyroidism in renal allograft recipients: vitamin D receptor, calcium-sensing receptor, and apoptosis.

The phenotypic changes in parathyroid cells after successful renal transplantation remain to be elucidated. We compared 10 diffuse and 11 nodular hyperplastic parathyroid glands from five renal allograft recipients with persistent hyperparathyroidism, with five diffuse and 13 nodular hyperplasia from seven uremic patients on hemodialysis, and 13 normal glands. Comparisons included expressions of both vitamin D receptor (VDR) and calcium-sensing receptor (CaSR), proliferative activity (Ki67), and apoptosis (TUNEL). Immunoreactivity was assessed semiquantitatively and expressed as labeling index. The area/cell was also measured to assess cellular hypertrophy. The labeling indexes of VDR (587+/-71; mean+/-s.e.m.) and CaSR (45.0+/-2.8) in recipients' diffuse hyperplasia were significantly higher than those in uremic diffuse hyperplasia (224+/-44, 29.3+/-2.3, respectively) (P<0.01, each). However, these expressions remained low in recipients' nodular hyperplasia (42+/-8, 11.8+/-1.4, respectively). Ki67 labeling index in recipients' nodular hyperplasia (7+/-1) was significantly smaller than in uremic patients (24+/-6, P<0.01). TUNEL labeling index in recipients' diffuse hyperplasia (30+/-5) was the highest among the groups. The cell volume tended to be smaller in both patterns of hyperplasia in allograft recipients compared with uremic patients. Our results suggest that the phenotypic change in parathyroid cells after renal transplantation depends on the pattern of hyperplasia, where it is normalized only in diffuse hyperplastic glands in which the number of cells also regresses with significant induction of apoptosis.

Apoptosis↗
PubMed2006

Parathyroid growth and regression in experimental uremia.

Early 1,25-dihydroxyvitamin D(3) (VD(3)) therapy during the course of renal failure prevents the downregulation of VD(3) receptor (VDR), calcium-sensing receptor (CaSR) or p21, and the parathyroid (PT) growth. We hypothesized that VD(3) could restore the decreased expressions of VDR and CaSR, and cause regression in enlarged PT glands. 5/6 nephrectomized rats fed high-phosphorus diet were killed at 1, 3, 5, or 7 days and at 2, 3, 4, 8, or 12 weeks. VD(3)-treated rats were given VD(3) intraperitoneally for 1, 2, 3, or 4 weeks, starting 8 weeks after 5/6 nephrectomy. PT glands were weighed and subjected to immunohistochemical analyses for VDR, CaSR, p21, Ki67, and Tdt-mediated dUTP nick end-labeling (TUNEL) assay. The area per cell was measured as the parameter of cell size. The expression of VDR and p21 began to decrease at day 1, and Ki67 increased at day 3, but decreased thereafter. There was a significant increase in PT gland weight to week 12 with the increase of cell size. VD(3) treatment significantly increased both VDR and CaSR expressions 2 weeks after the start of injection, and reduced the PT gland weight at week 3 with significant increase of TUNEL-positive cells and decrease of cell size. Our results suggest that PT growth in uremic rats involves both PT cell proliferation and hypertrophy, in association with the reduction of VDR, CaSR, and p21 expressions. In addition, VD(3) treatment could reverse PT hyperplasia and hypertrophy via restoration of these proteins.

Animals↗
PubMed1996

Reevaluation of superoxide scavenging activity of dihydrolipoic acid and its analogues by chemiluminescent method using 2-methyl-6-[p-methoxyphenyl]-3,7-dihydroimidazo-[1,2-a]pyrazine-3-one (MCLA) as a superoxide probe.

The superoxide scavenging activity of dihydrolipoic acid and its analogues has been reevaluated by a chemiluminescence method using MCLA as a superoxide indicator. The results demonstrated that all the compounds having the thiol chromophore in the molecule showed scavenging activity toward superoxide. The short-chain analogue, tetranor-dihydrolipoic acid, showed almost the same scavenging activity as that of dihydrolipoic acid; however, bisnor-dihydrolipoic acid showed weaker scavenging activity than that of dihydrolipoic acid. The reaction rates of dihydrolipoic acid, bisnor-dihydrolipoic acid, and tetranor-dihydrolipoic acid were calculated from the competitive inhibition of MCLA-superoxide reaction. Thus, it was concluded that dihydrolipoic acid and the analogues are good scavengers of superoxide radical anion.

Cysteine↗
PubMed1978

Mollicellins: mutagenic and antibacterial mycotoxins.

Eight mollicellins (depsidones) were assayed for mutagenicity and antibacterial activity in Salmonella/microsome tests involving histidine reversion and forward mutation to 8-azaguanine resistance. Two of them, mollicellins C and E, which contain a 3-methylbutenoic acid moiety, were mutagenic and bactericidal for Salmonella typhimurium in the absence of microsomes. Mollicellins D and F, each containing a chlorine atom, were bactericidal but not mutagenic. The mutagenic activity was completely abolished and the antibiotic activity was greatly reduced by coincubation with rat liver microsomes.

Animals↗