Biomedical subjects

Sanae Kishimoto

Publications and source records attributed to Sanae Kishimoto.

5 recordsLinked to original sources

PubMed2006

Carotenoid cleavage dioxygenase (CmCCD4a) contributes to white color formation in chrysanthemum petals.

The white petals of chrysanthemum (Chrysanthemum morifolium Ramat.) are believed to contain a factor that inhibits the accumulation of carotenoids. To find this factor, we performed polymerase chain reaction-Select subtraction screening and obtained a clone expressed differentially in white and yellow petals. The deduced amino acid sequence of the protein (designated CmCCD4a) encoded by the clone was highly homologous to the sequence of carotenoid cleavage dioxygenase. All the white-flowered chrysanthemum cultivars tested showed high levels of CmCCD4a transcript in their petals, whereas most of the yellow-flowered cultivars showed extremely low levels. Expression of CmCCD4a was strictly limited to flower petals and was not detected in other organs, such as the root, stem, or leaf. White petals turned yellow after the RNAi construct of CmCCD4a was introduced. These results indicate that in white petals of chrysanthemums, carotenoids are synthesized but are subsequently degraded into colorless compounds, which results in the white color.

Amino Acid Sequence↗

PubMed2005

Major role of soybean oil in preventing decrease in CYP4A1 mRNA content relative to PPARalpha mRNA down-regulation in infant rats.

Changes in the levels of CYP4A1, PPARalpha, and RXRalpha mRNA expression in the liver following overdose of fat-free or fat-containing total parenteral nutrition (TPN) were studied in 3-week-old male Sprague-Dawley rats. The rats were divided into three groups: group 1, oral diet; group 2, fat-free TPN; and group 3, TPN with 20% of calories from soybean oil emulsion. Levels of CYP4A1, PPARalpha, and RXRalpha mRNA in the fat-free TPN group were significantly lower than those in the other groups. Levels of CYP4A1 and PPARalpha mRNA were strongly correlated (r=0.849), and levels of CYP4A1 and RXRalpha mRNA were weakly correlated (r=0.618). This is the first report of a strong correlation between the levels of CYP4A1 and PPARalpha mRNA following overdose of fat-free or fat-containing TPN in infant rats. Our results also indicate that it is important to include fat in TPN regimens in order to prevent CYP4A1 mRNA down-regulation, which may be related to changes in PPARalpha mRNA levels in the liver.

Animals↗

PubMed2005

Analysis of carotenoid composition in petals of calendula (Calendula officinalis L.).

Nineteen carotenoids were identified in extracts of petals of orange- and yellow-flowered cultivars of calendula (Calendula officinalis L.). Ten carotenoids were unique to orange-flowered cultivars. The UV-vis absorption maxima of these ten carotenoids were at longer wavelengths than that of flavoxanthin, the main carotenoid of calendula petals, and it is clear that these carotenoids are responsible for the orange color of the petals. Six carotenoids had a cis structure at C-5 (C-5'), and it is conceivable that these (5Z)-carotenoids are enzymatically isomerized at C-5 in a pathway that diverges from the main carotenoid biosynthesis pathway. Among them, (5Z,9Z)-lycopene (1), (5Z,9Z,5'Z,9'Z)-lycopene (3), (5'Z)-gamma-carotene (4), and (5'Z,9'Z)-rubixanthin (5) has never before been identified. Additionally, (5Z,9Z,5'Z)-lycopene (2) has been reported only as a synthesized compound.

Calendula↗

PubMed2004

Carotenoid composition in petals of chrysanthemum (Dendranthema grandiflorum (Ramat.) Kitamura).

Sixteen xanthophylls were isolated from the petals of chrysanthemum (Dendranthema grandiflorum (Ramat.) Kitamura). Among them, (3S,5S,6R,3'R,6'R)-5,6-dihydro-5,6-dihydroxylutein (1) and five di-Z geometrical isomers of lutein-5,6-epoxide, i.e., 9Z,13'Z (2), 13Z,9'Z (3), 9'Z,13'Z (4), 9Z,13Z (5), and 9Z,9'Z (7), had never before been identified as natural products. All of the carotenoids isolated from chrysanthemum, except for (9Z)-violaxanthin, are beta,epsilon-carotene (alpha-carotene) derivatives. The analyses indicate that carotenoids from the petals of chrysanthemum have a very characteristic composition.

Carotenoids↗

PubMed2003

Four-week intravenous repeated dose toxicity study of L-cysteine in male rats.

A 4-week intravenous repeated dose toxicity study of L-cysteine (L-Cys) was conducted in male Sprague-Dawley rats to investigate in detail the toxic effects of this compound and to determine the dose level at which these toxic effects are observed following repeated intravenous administration. Male rats were randomly allocated to 4 groups to receive L-Cys by intravenous administration at dosages of 0, 100, 300, and 1,000 mg/kg body weight/day. Body weight gain was significantly suppressed throughout the study period in the 1,000-mg/kg group, although food consumption was reduced only on study day 3. A decrease in spontaneous activity, salivation, stereotypy, ptosis, and tremor were observed in the 1,000-mg/kg group. Mild anemia characterized by decreases in hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin and an increase in the reticulocyte count was also noted in the 1,000-mg/kg group. Histopathological examination showed sperm granulomas in the epididymis and necrosis of the Purkinje cells and granular layer in the cerebellum in the 1,000-mg/kg group. Slight tubular basophilia with blood or hyaline casts was observed in the kidney in the 300-mg/kg and 1,000-mg/kg groups, associated with proteinuria or occult blood in urinalysis. Additional studies are needed to clarify the causes for these toxicological findings by excess of L-Cys.

Animals↗