Biomedical subjects

Ayako Nagai

Publications and source records attributed to Ayako Nagai.

6 recordsLinked to original sources

PubMed2006

Vitamin E and C supplementation prevents decrease of eicosapentaenoic acid in mononuclear cells in chronic hepatitis C patients during combination therapy of interferon alpha-2b and ribavirin.

OBJECTIVE: We investigated the effects of vitamin E and C supplementation on the fatty acid composition of mononuclear cells and on the clinical observations in patients who had chronic hepatitis C and received interferon-alpha-2b (IFN-alpha-2b) and ribavirin combination therapy. METHODS: Patients were randomly allocated to receive daily 500 mg of vitamin E and 750 mg of vitamin C (vitamin group, n = 14) or no supplement (non-vitamin group, n = 16) in addition to IFN-alpha-2b and ribavirin therapy. The fatty acid composition of mononuclear cell phospholipids was analyzed before and at 2, 4, and 8 wk after treatment. RESULTS: After vitamin supplementation, plasma and red blood cell alpha-tocopherol and plasma ascorbic acid levels increased in the vitamin group. Serum levels of alanine aminotransferase decreased significantly after 2 wk of treatment in both groups. At the start of treatment, a lower level of eicosapentaenoic acid (EPA) and a higher level of the molar ratio of arachidonic acid to EPA in mononuclear cells were observed in the present patients compared with healthy volunteers, and a significant correlation between the molar ratio and serum alanine aminotransferase level was found. The EPA level of mononuclear cells was maintained in the vitamin group during treatment, whereas a significant decrease was observed in the non-vitamin group at 4 and 8 wk after treatment. CONCLUSIONS: Antioxidant vitamin supplementation during IFN-alpha-2b and ribavirin therapy prevented a decrease in EPA of mononuclear cell phospholipids. If a further decrease in the ratio of arachidonic acid to EPA can be achieved by using oral EPA supplementation, the efficacy of IFN-alpha-2b and ribavirin therapy may be improved.

Alanine Transaminase↗

PubMed2006

Alpha-tocopherol [corrected] and ascorbic acid attenuates the ribavirin [corrected] induced decrease of eicosapentaenoic acid in erythrocyte membrane in chronic hepatitis C patients.

BACKGROUND: Oxidative damage of the erythrocyte membrane plays an important role in ribavirin-induced anemia. The purpose of the present paper was to assess whether supplementation of alpha-tocopherol and ascorbic acid (vitamins) causes changes in the erythrocyte membrane fatty acid composition during interferon and ribavirin combination therapy for chronic hepatitis C patients. METHODS: Fatty acid compositions in erythrocyte membrane phospholipids were determined by gas chromatography at 0, 2, 4, 8 weeks, and at the end of combination therapy (26 weeks) for interferon with ribavirin in 32 patients with chronic hepatitis C who were randomized to receive vitamins or not (controls). RESULTS: Good compliance with orally administered vitamins and ribavirin were confirmed by their concentrations in erythrocytes or plasma. The hemoglobin level was negatively correlated with the ribavirin concentration at 8 weeks (r = 0.59, P = 0.01) after initiation of therapy in controls, but not in the vitamin group. Among the 26 kinds of fatty acids analyzed, only eicosapentaenoic acid (EPA) significantly decreased at 8 weeks after initiation of therapy (P = 0.03) and at the end of therapy (P = 0.004) in controls. Vitamins did not inhibit ribavirin-induced anemia, but attenuated the decrease of EPA in erythrocytes. The EPA level was negatively correlated with the drop in hemoglobin levels at 8 weeks after initiation of therapy in controls (r = 0.58, P = 0.015), but not in the vitamin group. CONCLUSIONS: Supplementation of alpha-tocopherol and ascorbic acid attenuates the ribavirin-induced decrease of EPA in erythrocyte membrane phospholipids in chronic hepatitis C patients.

Ascorbic Acid↗

PubMed2006

[A case of Werner syndrome with chromosomal abnormality].

A 52-year-old woman with diabetes mellitus (DM) complained of weakness of the arms and legs. She was referred to our hospital in November 2002 because of anemia, thyroid tumor and meningioma including DM. She was short in stature, juvenile bilateral cataract, intractable skin ulcers, clavus on the sole of her foot, a bird-like face and high-pitched voice. Typical physical features led to the final diagnosis of Werner's syndrome. Although the myelogram revealed no abnormal findings except erythroid hypoplasia, cytogenetic analysis of bone marrow cells showed deletion of chromosome 20 in 10% of the analyzed cells, which suggested the possibility of that myelodysplastic syndrome (MDS) or acute myeloblastic leukemia (AML) could occur. She had a thyroidectomy because both lobes of the thyroid gland were enlarged and caused hoarseness, In addition, it is common knowledge that the goiter could become malignant. We need to follow her carefully because she might be vulnerable to malignant disease, including leukemia and malignant meningioma.

Chromosome Deletion↗

PubMed2005

Isolation and identification of histone H3 protein enriched in microvesicles secreted from cultured sebocytes.

Secretion of microvesicles, defined as sebosomes, containing lipid particles were discovered for the first time in cultured sebocytes. After reaching confluency, hamster-cloned sebocytes released bubble-like microvesicles with a diameter range of 0.5-5.0 microm. They had a complex structure containing multiple Oil Red O-stainable particles. The lipid components of the microvesicles were large amounts of squalene both of hamster-cloned and rat primary cultured sebocytes. The microvesicles contained a concentrated 17-kDa cationic protein, which was soluble in sulfate buffer including Nonidet P-40 at pH 1.5. As the protein bound tightly to heparin-Sepharose and eluted with 1.5 M NaCl, it was further purified from a SDS-PAGE gel. Peptide sequencing identified the protein to be histone H3. Polyclonal antibodies against the purified protein detected the antigen in the microvesicles both in the hamster-cloned and rat primary cultured sebocytes. The antibodies demonstrated a distribution of the protein within the nucleus, cytoplasm, and precursor microvesicles. When a gene construct encoding histone H3-enhanced green fluorescent protein was transfected to the sebocytes, fluorescence of the fusion proteins was detected within both the nucleus and the precursor microvesicles of the cytoplasm. The distribution of heparan sulfate was evident in the microvesicles, and it suggested the possibility that the histone H3 protein was recruited and then condensed to the secreted microvesicles by the molecules. In addition, the 14-3-3 protein, which was detected in the microvesicles, also may help incorporate the histone H3 protein in the microvesicles because it can bind to both histone and lipid particles.

Animals↗

PubMed2005

Expression of perilipin A on the surface of lipid droplets increases along with the differentiation of hamster sebocytes in vivo and in vitro.

To clarify the involvement of perilipin, a lipid-droplet-surface protein associated with adipocytes and steroidogenic cells, in the differentiation of sebocytes, we investigated the expression of perilipin in sebaceous glands in vivo and in vitro. Perilipin was expressed in sebaceous glands of the hamster auricle in vivo and was localized at the surface of intracellular lipid droplets in differentiated hamster sebocytes in vitro. Western blot analysis showed that perilipin with a molecular weight of approximately 57 kDa, which was identical to that in differentiated mouse 3T3-L1 adipocytes, was detected in cultured sebocytes, indicating that sebaceous glands expressed perilipin A. In addition, the production of perilipin A in cultured sebocytes was transcriptionally augmented by sebocytic-lipogenesis stimulators, insulin, and 5alpha-dihydrotestosterone, whereas it was decreased by a suppressor of sebocytic differentiation, epidermal growth factor. Furthermore, hamster sebocytes were found to express peroxisome proliferation-activating receptor alpha and gamma1, the activation of which by WY14643 and troglitazone, respectively, caused the transcriptional augmentation of perilipin A expression along with an increase in levels of triacylglycerols in lipid droplets in sebocytes. Therefore, these results provide novel evidence that the expression of perilipin A increases on the surface of intracellular lipid droplets augmented along with the differentiation of hamster sebocytes.

3T3-L1 Cells↗

PubMed2004

Vitamin E supplementation increases polyunsaturated fatty acids of RBC membrane in HCV-infected patients.

OBJECTIVE: We investigated the effects of vitamin E supplementation on the fatty acid composition of red blood cell membrane phospholipids and on the clinical observations in patients with hepatitis C virus. METHOD: Eight patients and control subjects were administered 500 mg/d of d-alpha-tocopherol for 12 wk. The alpha-tocopherol and fatty acid composition of phospholipids in red blood cells were analyzed before, at 4, 8, and 12 wk, and after 4 wk of washout of vitamin E administration. RESULTS: The alpha-tocopherol concentration in red blood cells increased 2.37-fold of the basal level during vitamin E supplementation. Serum alanine aminotransferase levels increased in five of eight patients with vitamin E supplementation. The arachidonic acid level, docosahexaenoic acid level, and ratio of polyunsaturated to saturated fatty acid in red blood cell membrane phospholipids, which were significantly lower in the patients than in the control subjects, were elevated at 8 and 12 wk after vitamin E supplementation. The improvement in fatty acid composition was observed particularly in the patients who responded to the vitamin E therapy. CONCLUSIONS: Vitamin E therapy for the prevention of disease progression in patients with hepatitis C virus may be effective.

Alanine Transaminase↗