PolydextroseR (PD) is a water-soluble polysaccharide resistant to hydrolysis by digestive enzymes in the human gastrointestinal system. The effects of consumption of PD at 5-10g/day on the frequency and feeling of defecation were investigated in 22 healthy adolescent female volunteers in order to study the physiological response to PD in comparison with dietary fiber. The study was conducted by the Latin square method with a cross-over design. Drinks containing PD at concentrations of 0, 5, 7 and 10g/dl were prepared so that the subjects were able to take PD easily. The subjects took a bottled drink contained PD at a prescribed concentration daily for 5 successive days every week followed by a 2-day wash-out period. Daily intake of dietary fiber except that originating from the PD drink at each period of the study ranged from 8.0 to 8.8g, indicating no significant differences among the 4 periods of the study. The total intake of daily dietary fiber increased in proportion to the increment of PD intake. As the intake of PD increased, stools became softer with significant differences (p<0.05) observed between the periods when 7 and 10g of PD were taken and the period without PD. Stool hardness showed a significantly negative correlation (r=-0.387) with PD intake. However, the frequency and feeling of defecation were unaffected by PD intake. These results suggest that PD has an effect similar to that of dietary fiber.

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The usefulness of a soluble dietary fiber (0.6g carrageenan extracted from red algae) and protein (0.9g casein) mixture (FPM) for metabolic control was examined in 9 patients with non-insulindependent diabetes mellitus. FPM dissolved in 200ml of hot water was administered to each patient twice daily for 2 weeks. The body weight, plasma HbAlc and Apo B levels after treatment for 2 weeks were significantly lower than those before the treatment. Mixed meal loading without FPM after the 2-week treatment produced a less marked increase in plasma glucose and a higher increase in serum insulin in comparison with those before the treatment. The intake of FPM caused a feeling of stomach fullness in spite of calory restriction as a dietary regimen for the treatment of diabetes mellitus. These results suggest the usefulness of this fiber-protein mixture for metabolic control and prolongation of the feeling of stomach fullness in patients with non-insulin-dependent diabetes.

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During the course of a study on the deleterious effects of sucrose, we previously demonstrated that prolonged excess sucrose administration increased the liquid intake and urine volume of rats, and produced a diabetes-like pathema. It was also shown that urinary Ca and P excretion, and the levels of blood glucose, pyruvic and lactic acids were increased, indicative of metabolic acidosis. In order to clarify the above observations, the present study was undertaken to investigate the digestion and absorption of sucrose and also sucrase activity in the small intestinal mucosa of rats following prolonged administration of excess sucrose. Wistar-strain male rats were divided into 2 groups (5 rats/group): Group 1 (G1) and Group 2 (G2) were given purified water and 10% sucrose ad libitum for 5 months, respectively. The rats were then fasted for 24h and anesthetized with pentobarbital. Perfusion cannulae were inserted from the upper duodenum and lower ileum. Sodium phosphate buffer (37°C) containing sucrose was perfused at a rate of 1ml/min via the upper cannula for 60min. Fractions (4ml) were then collected via the lower cannula and subjected to glucose and sucrose assays. Sucrase activity in the small intestinal mucosa was also determined. The rates of digestion and absorption of sucrose in G2 were significantly increased, together with a remarkable increase of sucrase activity. Significant relationships between sucrose digestion-absorption and sucrase activity were obtained in both G1 and G2. These results indicate that prolonged excess sucrose intake in rats results in increased sucrose digestion and a higher absorption rate due to enhanced sucrase activity.

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The effects of fasting and thyroid function on changes in liver lipid content and serum free fatty acid (FFA) concentration in adrenalectomized (ADX) rats fed a high-fat diet were examined and compared with those in ADX rats fed a high-carbohydrate diet.
Liver lipid content in rats fed the high-fat diet was unchanged by fasting regardless of adrenal status, whereas lipid accumulation in the liver caused by fasting occurred in rats fed the high-carbohydrate diet. The lipid content of the liver was slightly decreased by adrenalectomy and restored by cortisone administration. Response of liver lipids to thyroid function was observed in cortisone treated ADX (ADX-C) rats and the lipid content of the liver during fasting was highest in hypothyroid rats. Serum FFA levels in rats fed the high-fat diet were increased by fasting, but no relation was observed between serum FFA levels during fasting and adrenal function. Rats given a sham operation showed responses of serum FFA to thyroid function and the highest FFA level was found in hyperthyroid rats, whereas ADX and ADX-C rats did not show such responses. These findings suggest that the effects of fasting and thyroid function might differ in the regulation of liver lipid accumulation, and that glucocorticoid action might be related to the mechanism associated with thyroid function.

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Fresh erythrocytes obtained from senescence-accelerated mice, both prone (SAM-P/1) and resistant (SAM-R/1) strains, were separated into 4 different cell density, i. e. cell age, fractions by densitygradient centrifugation. The specific activities of pyruvate kinase and hexokinase, which are known to be marker enzymes of cell age for erythrocytes, decreased with increased erythrocyte cell density in both strains of mouse, and in some cell fractions were higher in SAM-P/1 than in SAM-R/1. The specific activity of glutathione reductase decreased with increased cell density in both strains. The specific activity of glutathione peroxidase also decreased with increased cell density in both strains, but was lower in most fractions from SAM-P/1 than in the corresponding fractions from SAM-R/1.
The level of oxidized protein assessed by reactivity with 2, 4-dinitrophenylhydrazine increased with the increase in cell density in both strains of mouse and was higher in all the fractions from SAM-P/1 than in those from SAM-R/1. These results are interpreted to indicate that the aging process is accelerated in the erythrocytes of SAM-P/1, and that this acceleration is partly associated with some defect in the cellular oxidant defense mechanism, including glutathione peroxidase.

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In the present study we investigated the effects of palatinose and its condensates (PC) on mineral concentrations in various tissues of rats. Thirty Wistar rats were divided equally into 5 groups and given the following diets and double-distilled water ad libitum for 8 weeks: 30% sucrose (control), 30% palatinose, 10% PC, 20% PC, 30% PC. Body weight of the 30% PC group was significantly lower than that of the control. There were no significant differences in mineral concentrations (Ca, Mg and P) in tissues between the control and other groups, except for the plasma P concentration in the 30% PC group, which was significantly higher than that of the control. These results suggest that no remarkable change in tissue mineral concentrations is induced in rats by palatinose or PC.

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A study was conducted to investigate the effects of hydrocortisone and vitamin D₃ on the fatty acid composition of the duodenal brush border membranes in developing chick embryos, and to observe whether such effects on membrane lipids are related to the developmental induction of membranebound enzyme activity. Hydrocortisone was administered to embryos on days 14 and 17 of incubation, and vitamin D₃ was administered on day 14 of incubation. The duodenal brush border membranes were isolated from the pooled duodenal mucosa of 10 or 15 embryos on day 20 of incubation. The administration of hydrocortisone resulted in an increase of duodenal mucosa weight and DNA content of the duodenal mucosa in 20-day-old embryos. The embryonic membrane protein in the duodenal brush border was also increased through this treatment. However, there was no increase of membrane protein as expressed per unit of mucosal DNA. Administration of vitamin D₃ had no effects on these parameters. The fatty acid composition of the duodenal brush border membranes was changed by both hydrocortisone and vitamin D₃ administration. The polyunsaturated fatty acid levels of ω6 acids such as 18: 2 (ω6) and 20: 4 (ω6) were significantly increased by both treatments. Hydrocortisone administration enhanced the specific activities of sucrase and alkaline phosphatase in the duodenal brush border membrane af 20-day-old chick embryos. However, vitamin D₃ treatment increased alkaline phosphatase activity anly. Induction of alkaline phosphatase related to a change in fatty acid composition was thus caused by treatment with either hydrocortisone or vitamin D₃. Sucrase induction was not related to alteration of membrane lipids. These results suggest that hydrocortisone as well as vitamin D₃ might be involved in the developmental induction of membrane-bound enzyme (alkaline phosphatase) activity, affecting membrane fluidity through alteration of the membrane fatty acid composition.

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Thermal decomposition of added tocopherol (Toc) by fatty acids and their methyl esters differing in their numbers of carbon atoms and degree of unsaturation, and the preventive effect of gallic and thiodipropionic acids were investigated. Test samples were heated in a Pyrex glass tube (2.7×20cm) at 180°C, and residual Toc, anisidine and carbonyl values were determined. Thermal decomposition of Toc by methyl esters of saturated fatty acids occurred in the order of stearate>laurate>caprylate. The oxidation products (Toc dimer and trimer etc.) of Toc in methyl stearate increased with the heating time. In the case of unsaturated fatty acids and their methyl esters, Toc in oleic acid (or ester) was more extensively decomposed by oleic acid (or its ester) than by linoleic and linolenic acids (or their esters), but the anisidine and carbonyl values with oleic acid (or its ester) were markedly low. The degree of Toc loss after heating was also much greater with methyl stearate than with methyl esters of unsaturated fatty acid. In comparison with oleic acid, monoolein and triolein, Toc was greatly decreased by oleic acid. On the other hand, the amount of residual Toc was higher with monoolein. Gallic and thiodipropionic acids suppressed the thermal decomposition of Toc by methyl stearate and oleate.

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