Biomedical subjects

Takanori Tsuda

Publications and source records attributed to Takanori Tsuda.

10 recordsLinked to original sources

PubMed2006

Microarray profiling of gene expression in human adipocytes in response to anthocyanins.

Adipocyte dysfunction is strongly associated with the development of obesity and insulin resistance. It is accepted that the regulation of adipocytokine secretion or the adipocyte specific gene expression is one of the most important targets for the prevention of obesity and amelioration of insulin sensitivity. Recently, we demonstrated that anthocyanins, which are pigments widespread in the plant kingdom, have the potency of anti-obesity in mice and the enhancement adipocytokine secretion and its gene expression in adipocytes. In this study, we have shown the gene expression profile in human adipocytes treated with anthocyanins (cyanidin 3-glucoside; C3G or cyanidin; Cy). The human adipocytes were treated with 100 microM C3G, Cy or vehicle for 24 h. The total RNA from the adipocytes was isolated and carried out GeneChip microarray analysis. Based on the gene expression profile, we demonstrated the significant changes of adipocytokine expression (up-regulation of adiponectin and down-regulation of plasminogen activator inhibitor-1 and interleukin-6). Some of lipid metabolism related genes (uncoupling protein2, acylCoA oxidase1 and perilipin) also significantly induced in both common the C3G or Cy treatment groups. These studies have provided an overview of the gene expression profiles in human adipocytes treated with anthocyanins and demonstrated that anthocyanins can regulate adipocytokine gene expression to ameliorate adipocyte function related with obesity and diabetes that merit further investigation.

Adipocytes↗

PubMed2006

Ingested delphinidin-3-rutinoside is primarily excreted to urine as the intact form and to bile as the methylated form in rats.

Many reports have described the bioavailability of anthocyanins; however, most of these reports investigated only the amount of anthocyanins excreted in urine. In the present study, we calculated the pharmacokinetic bioavailability of anthocyanins in rats by measuring the plasma concentration of delphinidin-3-rutinoside that had been administered orally or intravenously. Delphinidin-3-rutinoside was primarily absorbed in the blood and excreted into urine as unmetabolized forms with a T(max) of 26.3 min and a C(max) of 0.285 +/- 0.071 micromol/L. We detected small amounts of the metabolite 4'-O-methyl-delphinidin-3-rutinoside in the plasma, but we detected neither anthocyanidin (aglycone) nor glucuro- or sulfoconjugates. For the 8 h period after intake, delphinidin-3-rutinoside and 4'-O-methyl-delphinidin-3-rutinoside were excreted to urine at 795 +/- 375 and 12.3 +/- 2.91 nmol, respectively. Relative to intravenous injection, oral administration of delphinidin-3-rutinoside resulted in complete bioavailability (0.49 +/- 0.06%). Analysis of delphinidin-3-rutinoside plasma concentrations in bile cannulated rats revealed that, for the 8-h period after intake, the intact delphinidin-3-rutinoside excretion ratio in bile was 11% of the excretion ratio of 4'-O-methyl-delphinidin-3-rutinoside, 1.91 +/- 0.35 nmol versus 17.4 +/- 8.67 nmol, respectively. Setting the bile duct cannulation in a Bollman-type cage, however, significantly increased the bioavailability of orally administered delphinidin-3-rutinoside (18.14 +/- 6.24%). This effect appears to stem immobilization stress by reducing gastrointestinal motility. The cumulative excretion of delphinidin-3-rutinoside and 4'-O-methyl-delphinidin-3-rutinoside in urine and bile was 2.67 +/- 1.24% (w/w) of the dose ingested. Studies report that several metabolites are formed after oral ingestion of anthocyanins. Examples include glucuronyl from cyanidin-3-glucoside and both glucuronyl and sulfate conjugates from pelargonidin-3-glucoside. Our results indicate that delphinidin-3-rutinoside might be metabolized differently from cyanidin-3-glucoside and pelargonidin-3-glucoside.

Animals↗

PubMed2006

Ascorbic acid deficiency stimulates hepatic expression of inflammatory chemokine, cytokine-induced neutrophil chemoattractant-1, in scurvy-prone ODS rats.

ODS rat has a hereditary defect in ascorbic acid biosynthesis and is a useful animal model for elucidating the physiological role of ascorbic acid. We previously demonstrated by using ODS rats that ascorbic acid deficiency changes the hepatic gene expression of acute phase proteins, as seen in acute inflammation. In this study, we investigated the effects of ascorbic acid deficiency on the production of inflammatory chemokine, cytokine-induced neutrophil chemoattractant-1 (CINC-1), in ODS rats. Male ODS rats (6 wk of age) were fed a basal diet containing ascorbic acid (300 mg/kg diet) or a diet without ascorbic acid for 14 d. Obvious symptoms of scurvy were not observed in the ascorbic acid-deficient rats. Ascorbic acid deficiency significantly elevated the serum concentration of CINC-1 on d 14. The liver and spleen CINC-1 concentrations in the ascorbic acid-deficient rats were significantly elevated to 600% and 180% of the respective values in the control rats. However, the lung concentration of CINC-1 was not affected by ascorbic acid deficiency. Ascorbic acid deficiency significantly elevated the hepatic mRNA level of CINC-1 (to 480% of the value in the control rats), but not the lung mRNA level. These results demonstrate that ascorbic acid deficiency elevates the serum, liver and spleen concentrations of CINC-1 as seen in acute inflammation, and suggest that ascorbic acid deficiency stimulate the hepatic CINC-1 gene expression.

Animals↗

PubMed2005

Gene expression profile of isolated rat adipocytes treated with anthocyanins.

Adipocyte dysfunction is strongly associated with the development of obesity and insulin resistance. It is accepted that the regulation of adipocytokine secretion or the adipocyte specific gene expression is one of the most important targets for the prevention of obesity and amelioration of insulin sensitivity. Recently, we demonstrated that anthocyanins, which are pigments widespread in the plant kingdom, have the potency of anti-obesity in mice and the enhancement adipocytokine secretion and adipocyte gene expression in adipocytes. In this study, we have shown for the first time the gene expression profile in isolated rat adipocytes treated with anthocyanins (cyanidin 3-glucoside; C3G or cyanidin; Cy). The rat adipocytes were treated with 100 muM C3G, Cy or vehicle for 24 h. The total RNA from the adipocytes was isolated and carried out GeneChip microarray analysis. A total of 633 or 427 genes was up-regulated (>1.5-fold) by the treatment of adipocytes with C3G or Cy, respectively. The up-regulated genes include lipid metabolism and signal transduction-related genes, however, the altered genes were partly different between the C3G- and Cy-treated groups. Based on the gene expression profile, we demonstrated the up-regulation of hormone sensitive lipase and enhancement of the lipolytic activity by the treatment of adipocytes with C3G or Cy. These data have provided an overview of the gene expression profiles in adipocytes treated with anthocyanins and identified new responsive genes with potentially important functions in adipocytes related with obesity and diabetes that merit further investigation.

Adipocytes↗

PubMed2004

Absorption and metabolism of delphinidin 3-O-beta-D-glucopyranoside in rats.

The absorption and metabolism of delphinidin 3-O-beta-d-glucopyranoside (Dp3G), which is the most potent antioxidant among the blueberry anthocyanins, were studied in rats. Dp3G rapidly appeared in the blood plasma within 15 min of oral administration (100 mg/kg body wt). The plasma level of absorbed Dp3G showed two peaks at 15 and 60 min after ingestion and then decreased time-dependently. However, the plasma level was maintained at approximately 30 nmol/l even after 4 h. Besides the Dp3G peak, a single major metabolite peak was detected by HPLC in the blood plasma obtained at 15 min. MS and NMR spectroscopy clarified that the chemical structure of the metabolite was 4'-O-methyl delphinidin 3-O-beta-d-glucopyranoside (methylation of the 4'-OH on the delphinidin B-ring). The present finding of this unique metabolite in anthocyanin metabolism strongly suggests that methylation of the 4'-OH on the flavonoid B-ring is a common metabolic pathway for flavonoids that carry the pyrogallol structure on the B-ring, as the same type of metabolite has been reported for other flavonoids such as epigallocatechin, but not for flavonoids carrying the catechol structure.

Administration, Oral↗

PubMed2004

Anthocyanin enhances adipocytokine secretion and adipocyte-specific gene expression in isolated rat adipocytes.

Adipocyte dysfunction is strongly associated with the development of obesity and insulin resistance. It is accepted that the regulation of adipocytokine secretion or the adipocyte-specific gene expression is one of the most important targets for the prevention of obesity and amelioration of insulin sensitivity. In this study, we demonstrated that anthocyanins (cyanidin or cyanidin 3-glucoside) have the potency of a unique pharmacological function in isolated rat adipocytes. Treated adipocytes with anthocyanins enhanced adipocytokine (adiponectin and leptin) secretion and up-regulated the adipocyte specific gene expression without activation of PPARgamma in isolated rat adipocytes. The gene expression of adiponectin was also up-regulated in white adipose tissue in mice fed an anthocyanin supplemented diet. As one of the possible mechanisms, AMP-activated protein kinase activation would be associated with these changes, nevertheless, the AMP:ATP ratio was significantly decreased by administration of the anthocyanins. These data suggest that anthocyanins have a potency of unique therapeutic advantage and also have important implications for preventing obesity and diabetes.

AMP-Activated Protein Kinases↗

PubMed2003

Dietary cyanidin 3-O-beta-D-glucoside-rich purple corn color prevents obesity and ameliorates hyperglycemia in mice.

Anthocyanins, which are used as a food coloring, are widely distributed in human diets, suggesting that we ingest large amounts of anthocyanins from plant-based foods. Mice were fed control, cyanidin 3-glucoside-rich purple corn color (PCC), high fat (HF) or HF + PCC diet for 12 wk. Dietary PCC significantly suppressed the HF diet-induced increase in body weight gain, and white and brown adipose tissue weights. Feeding the HF diet markedly induced hypertrophy of the adipocytes in the epididymal white adipose tissue compared with the control group. In contrast, the induction did not occur in the HF + PCC group. The HF diet induced hyperglycemia, hyperinsulinemia and hyperleptinemia. These perturbations were completely normalized in rats fed HF + PCC. An increase in the tumor necrosis factor (TNF)-alpha mRNA level occurred in the HF group and was normalized by dietary PCC. These results suggest that dietary PCC may ameliorate HF diet-induced insulin resistance in mice. PCC suppressed the mRNA levels of enzymes involved in fatty acid and triacylglycerol synthesis and lowered the sterol regulatory element binding protein-1 mRNA level in white adipose tissue. These down-regulations may contribute to triacylglycerol accumulation in white adipose tissue. Our findings provide a biochemical and nutritional basis for the use of PCC or anthocyanins as a functional food factor that may have benefits for the prevention of obesity and diabetes.

Adipose Tissue↗

PubMed2002

Increase in oxidative stress in kidneys of diabetic Akita mice.

New biomarkers for oxidative damage, were used to identify whether hyperglycemia caused oxidative stress in diabetic Akita mice. At 13 weeks of age, the tissues of these mice were obtained, and the levels of N(epsilon)-(hexanonyl)lysine (HEL) and dityrosine (DT) were measured, these being related to lipid peroxide-derived protein covalent modification and protein cross-linking. The levels of HEL and DT in the kidneys of Akita mice were significantly increased compared with the control mice without any accumulation of thiobarbituric acid reactive substances and 4-hydroxy-2-nonenal-modified protein. Immunopositive staining was clearly observed in the kidneys of the Akita mice when using the anti-HEL antibody or anti-DT antibody. These results suggest that hyperglycemia in Akita mice induced oxidative stress and increased these markers in the kidneys.

Animals↗

PubMed2002

Cyanidin 3-O-beta-D-glucoside attenuates the hepatic ischemia-reperfusion injury through a decrease in the neutrophil chemoattractant production in rats.

We have shown that the orally administered cyanidin 3-O-beta-D-glucoside (C3G) attenuates the hepatic ischemia-reperfusion (I/R) injury, which was used as a model for oxidative stress through a decrease in neutrophil chemoattractant production in rats. The rats were subjected to hepatic I/R at 30 min after the administration of C3G (0.9 mmol/kg body weight) or vehicle. I/R treatment resulted in the elevation of oxidative stress marker [liver thiobarbituric acid-reactive substance, Nepsilon-(hexanonyl) lysine and dityrosine] levels in the liver and of the serum activities of marker enzymes for liver injury. The administration of C3G significantly suppressed these elevations, which had been caused by hepatic I/R. Liver myeloperoxidase activity, a useful marker for neutrophil infiltration into tissues, and the plasma and liver concentration of cytokine-induced neutrophil chemoattractant-1 (CINC-1), which has a potent chemotactic activity, were markedly elevated in the control group after hepatic I/R. However, these elevations were significantly suppressed in the C3G group. C3G and its metabolites in the plasma and liver were detected in the C3G group after hepatic I/R. These results suggest that the absorbed C3G and/or its metabolites can act as antioxidants in the blood and liver and scavenge the reactive oxygen species, and brought on a decrease in neutrophil infiltration into the liver through the suppression of CINC-1 production and the tissue damage caused by neutrophils after I/R is attenuated.

Animals↗

PubMed2002

Cyanidin 3-O-beta-D-glucoside suppresses nitric oxide production during a zymosan treatment in rats.

Anthocyanins are used for food color, and they are widely distributed in the human diets, suggesting that we ingest considerable amounts of anthocyanins from plant-based daily diets. We have demonstrated that a typical anthocyanin, cyanidin 3-O-beta-D-glucoside (C3G), suppressed the zymosan-induced inflammatory response in rats when it was orally administered. The elevation of the peritoneal exudate NOx, tumor necrosis factor (TNF) alpha interleukin-1beta (IL-1beta), IL-6, and the cytokine-induced neutrophil chemoattractant-1 (CINC-1) concentrations were significantly suppressed by the administration of C3G. The zymosan treatment resulted in an increase in the serum alpha2-macroglobulin and decreases in the serum albumin and transferrin levels, which are recognized as acute phase proteins. However, these levels were normalized by the administration of C3G. The inducible nitric oxide synthase (iNOS) protein level in the peritoneal exudate cells was markedly elevated in the control group treated with zymosan. However, the administration of C3G significantly reduced the level of iNOS in the peritoneal exudate cells. Taken altogether, our findings provide a biochemical basis for the use of C3G as a functional food factor and can also have important implications for the prevention of the NO-mediated inflammatory diseases.

Acute-Phase Proteins↗