Biomedical subjects

Teruhiko Matsushima

Publications and source records attributed to Teruhiko Matsushima.

5 recordsLinked to original sources

PubMed2005

Determination of apolipoprotein B-48 in serum by a sandwich ELISA.

BACKGROUND: Apolipoprotein B-48 (apoB-48) is produced by the small intestine, as a part of chylomicrons (CMs), and appears to be a suitable marker for clinical studies of postprandial lipoproteins and related cardiovascular risk factors. We have developed an assay for routine analysis to quantify apoB-48 in serum or plasma. METHODS: A microtiter plate was coated with monoclonal antibody (4C8) raised against apoB-48 C-terminal specific decapeptide. Serum samples were diluted 100-fold with 0.05 mol/l Tris-HCl buffer (with or without 0.1% Triton X-100). Appropriate calibration curves were obtained in the ELISA by using apoB-48 recombinant antigen. RESULTS: No cross-reactivity (<0.001%) was found with apoB-100, as verified by ELISA and Western blot analyses. Intra- and inter-assay CVs were 4.8% and 5.4%, respectively. Recovery of added recombinant apoB-48 in serum was within 94-105%. The assay linearity was intact >5-fold dilution of serum by dilution buffer. ApoB-48 levels in healthy controls (n=18) at fasting were within the range of 2.69-6.56 microg/ml (mean+/-S.D.: 4.60+/-1.54 microg/ml). In healthy subjects, serum apoB-48 concentrations markedly increased in the postprandial state, in parallel with serum triglycerides. CONCLUSION: This method for measuring apoB-48 using the monoclonal antibody 4C8 is simple, reliable and suitable for routine analyses.

Adult↗

PubMed2004

Clinical efficacy and safety of rosuvastatin in Japanese patients with heterozygous familial hypercholesterolemia.

Rosuvastatin is a new statin that has been shown to produce substantial dose-dependent reductions in low-density lipoprotein cholesterol (LDL-C) in Western and Japanese hypercholesterolemic patients. Rosuvastatin efficacy and safety were assessed in an open-label, dose-titration trial of 37 Japanese patients with heterozygous familial hypercholesterolemia. After an 8-week dietary lead-in period, patients received rosuvastatin on the following schedule: 10 mg/day during weeks 0-6; 20 mg/day during weeks 6-12, and 40 mg/day for weeks 12-18. Mean percentage reductions from baseline in LDL-C (49.2-56.7%), total cholesterol (39.4-45.4%), and non-high-density lipoprotein cholesterol (non-HDL-C) (46.7-54.3%) were highly significant at each dose (p < 0.0001). Similar significant reductions in triglycerides (18.2-25.0%; p < 0.006) and increases in HDL-C (9.6-13.6%; p < 0.005) were observed. Rosuvastatin was well tolerated. Two patients withdrew from the study because of adverse events unrelated to the study treatment. No patients had clinically significant elevations in liver transaminases. Two patients exhibited a single increase in creatine kinase (one unrelated to study treatment, the other possibly related) with no muscle symptoms. Rosuvastatin produced significant beneficial changes in all lipid parameters in Japanese patients with heterozygous familial hypercholesterolemia and was well tolerated.

Asian People↗

PubMed2003

Pravastatin at 10 mg/day does not decrease plasma levels of either amyloid-beta (Abeta) 40 or Abeta 42 in humans.

It has been assumed that statins work as a preventative drug for Alzheimer's disease (AD). Although some epidemiological observations raise doubts to the effectiveness of statins for AD, many in vitro and clinical studies insist on the effectiveness of statins decreasing amyloid-beta (Abeta) levels in medium or blood. To explore the effect of pravastatin on Abeta production, we followed the longitudinal plasma levels of both Abeta 40 and Abeta 42 during the allocation of pravastatin in 46 patients with hyperlipidemia. We found no correlation between plasma cholesterol levels or the decreasing values of total cholesterol and those of Abeta 40 or Abeta 42. Patients having Apolipoprotein E4 (ApoE4) had higher low-density lipoprotein levels and lower Abeta 40 levels in plasma, suggesting ApoE4 seems to influence plasma Abeta levels via cholesterol metabolism.

Adult↗

PubMed2003

Isoform-dependent cholesterol efflux from macrophages by apolipoprotein E is modulated by cell surface proteoglycans.

OBJECTIVE: Apolipoprotein E (apoE) mediates cellular cholesterol efflux and plays a crucial role in the inhibition of atherogenesis. We investigated whether there is an isoform-specific difference in its function for cholesterol efflux from cholesterol-loaded RAW264.7 cells, a murine macrophage cell line that lacks endogenous apoE expression. METHODS AND RESULTS: When human apoE was expressed in RAW264.7 cells, apoE2 reduced cellular total cholesterol (TC) and esterified cholesterol (EC) levels significantly, whereas apoE3 and apoE4 had no effect. However, treatment of cells with 4-methylumbelliferyl-7-beta-D-xyloside (beta-DX) resulted in all 3 isoforms' reducing cellular TC and EC contents significantly. We also investigated the effect of exogenously derived apoE on cholesterol efflux by utilizing the medium harvested from HeLa cells expressing apoE. ApoE2 and E3 reduced both cellular TC and EC contents significantly, whereas apoE4 did not. However, treatment of the cells with beta-DX resulted in all 3 exogenously derived apoE isoforms' reducing TC and EC contents significantly. The binding ability of apoE to heparan sulfate proteoglycans examined by heparinase I treatment revealed less binding ability of apoE2 compared with that of apoE3 or apoE4. CONCLUSIONS: The present study clarified the differential cellular cholesterol-modulating effect of apoE isoforms in macrophages, which would be due to the difference in their binding to proteoglycans.

Adenoviridae↗

PubMed2002

Intracellular fatty acid downregulates ob gene expression in 3T3-L1 adipocytes.

The effect of intracellular free fatty acid (FFA) accumulation on ob gene expression in adipocytes was examined. In fully differentiated 3T3-L1 adipocytes, triacsin C, a specific acyl CoA synthetase inhibitor with a K(i) of 8.97 microM, inhibited ob gene expression by 20% at 5 x 10(-5)M. At this concentration, triacsin C induced accumulation of intracellular FFA. Treatment with both chylomicron and triacsin C reduced ob gene expression more than treatment with triacsin C alone. Treatment with 2-bromopalmitate, a poorly metabolizable palmitate analog, reduced ob gene expression by 50% at 10(-4)M, but palmitate at the same concentration had no effect. This is the first demonstration that the ob gene is downregulated by intracellular FFA accumulation, thereby raising the possibility that ob product is regulated in response to lipolysis.

3T3 Cells↗