Feed containing 0.7% 4^G-β-D-galactosylsucrose (lactosucrose, LS), a non-digestible oligosaccharide, was given to weanling rats aged 4 to 12 weeks to investigate the effects of LS ingestion on bone. During the test period of ingestion, the quantity of feed ingested and the amount of weight gain did not differ between the LS group and the control group. In addition, there were no abnormalities of fecal quality such as diarrhea due to administration of LS. During the period of LS ingestion, the femoral and tibial cancellous area was significantly greater in the LS group than in the control group. Tibial cancellous cartilage area after 4, 5, and 8 weeks of LS ingestion was significantly greater in the LS group than in the control group (p<0.05). During week 6 of LS ingestion, the breaking force of the femur and tibia was significantly better in the LS group than in the control group. Femoral and tibial calcium content and lumbosacral bone mineral density as measured by dual-energy X-ray densitometry (DEXA) were significantly higher in the LS group than in the control group. However, calcium metabolism-related parameters such as alkaline phosphatase (ALP), serum calcitonin, and parathyroid hormone (PTH) showed no significant changes. The above findings suggest that LS ingestion moderately stimulates osteogenesis and helps to maintain bone strength.

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Increased intake of dietary fat is in general associated with obesity, hyperlipidaemia, hypertension, and impaired glucose tolerance, which are all major risk factors for coronary heart disease. However, an olive oil-rich diet, rich in monounsaturated oleic acid, is known to be associated with decreased risk of coronary heart disease. In this study, we investigated the effect of another oleic acid-rich oil, tea oil (oil of Camelia oleifera seeds), in comparison with olive oil, on increase of body and adipose tissue weight, plasma lipoprotein profile, and factors affecting lipoprotein metabolism in rats, using polyunsaturated fatty acid-rich soybean oil and saturated fatty acid-rich palm oil as controls. Sprague-Dawley rats, 7 weeks old, were fed a high-fat diet containing 16% (w/w) soybean oil, olive oil, tea oil, or palm oil for 5 weeks. There were no differences in body weight, adipose tissue weight, and ratio of body weight increase to food consumption between the different groups. Serum cholesterol (TC) was lower with either olive, tea, or palm oil than with soybean oil, and the changes were due mostly to a decrease in high-density lipoprotein cholesterol (HDL-C). The serum triglyceride (TG) level tended to be higher with olive oil than with soybean oil, but there were no changes with tea oil. Very-low-density lipoprotein cholesterol (VLDL-C) and triacylglycerol increased with olive oil, but not with tea oil, while intermediate-density lipoproteins (IDL) and low-density lipoproteins (LDL) did not change in either case, suggesting increased VLDL production and increased LDL clearance with olive oil and no such changes with tea oil. However, VLDL secretion measured by the Triton WR-1339 method in a separate experiment revealed an increase of the VLDL-C secretion rate but not the VLDL-TG secretion rate with both olive oil and tea oil. The fatty acid composition of the serum and lipoprotein fractions closely reflected that of dietary oil, but the relationship was closes for VLDL and less close for HDL. These results suggest that an oleic acid-rich diet affects the lipoprotein profile by increasing both VLDL secretion and clearance of serum lipoproteins. Additionally, the content and composition of plant sterols in olive oil and tea oil are very different, suggesting a profound effect of dietary plant oil on serum lipid and lipoprotein profiles.

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The age distribution of urinary free deoxypyridinoline (free-Dpyr) was investigated in 242 healthy women, aged 18 to 78 years. Moreover, we evaluated the relationship between free-Dpyr and BMD (lumbar spine and calcaneus) or a history of fracture. BMD decreased with advancing age. C-BMD showed a significant negative correlation with age, not only in the 50-79-year age group but also the 20-49-year age group. Concerning free-Dpyr levels, no significant difference among the 20-49-year age group was found, but those in the 50-79-year age group were significantly higher than those in the 20-49-year age group. Women with both a low value of lumbar spine BMD and high free Dpyr levels were at greater risk of fracture than those with only low BMD or high bone resorption. These findings suggest that combined measurement of BMD with free Dpyr is useful for improving the assessment of bone health and the risk of fracture in women.

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Rats were provides with one of the following diets ad libitum; cornstarch (CS), 2.5% psyllium (PS), 2.5% high-amylose cornstarch (HAS) and 2.5% PS+2.5% HAS for 4 weeks. Supplementation of HAS and/or PS into the diets was done at the expense of the same amount of CS. Cecal butyrate concentrations were significantly higher in rats fed the 2.5% HAS diet than in those fed the CS, 2.5% PS and 2.5% PS+2.5% HAS diets. However, butyrate concentrations in rats fed the 2.5% HAS diet decreased along the colon from a proximal to a distal direction, and there were no significant differences in fecal butyrate concentration between the groups fed the 2.5% HAS and CS diets. In contrast, the 2.5% PS+2.5% HAS diet-fed group maintained a higher butyrate concentration throughout the large bowel. Fecal butyrate concentrations in this group were significantly higher than those in the group fed the 2.5% HAS diet. Fecal starch excretion was significantly higher in rats fed the 2.5% PS+2.5% HAS diet than in those fed the 2.5% HAS diet. There was a significant and positive correlation between fecal starch excretion and fecal butyrate concentration. These results suggest that ingestion of PS with HAS increases the butyrate concentration in the distal colon and feces, presumably by controlling the fermentation rate of HAS in the cecum and shifting the fermentation site of HAS toward the distal colon.

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The aim of the present study was to determine the effect of a magnesium (Mg)-deficient diet on phosphatidylcholine hydroperoxide (PCOOH) and phosphatidylethanolamine hydroperoxide (PEOOH) levels in relation to changes in tissue mineral distribution in rats. Weanling (3-week-old) male Wistar rats were divided into two groups: a normal diet (N) group (0.05%Mg) and a Mg-deficient diet (D) group (0.006% Mg). The D group showed an increased PCOOH level and iron content in the liver and heart compared with the N group. The D group showed a higher PCOOH level and copper content in the plasma and erythrocyte membrane than the N group. Either superoxide dismutase (SOD) or glutathione peroxidase (GPX) activity was decreased in the liver, heart, kidney and plasma of the D group. The level of urinary 8-hydroxydeoxyguanosine (8-OHdG), a marker of oxidative DNA damage, was 2-fold higher in the D group than in the N group. The increase in the urinary 8-OHdG level suggested oxidative DNA damage to tissues. It is concluded that a change of iron or copper induces phospholipid hydroperoxidation by increasing of PCOOH or PEOOH in the liver, heart, plasma and erythrocyte membrane of Mg-deficient rats.

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Dietary triacylglycerol (TG) is known to be a source of body fat. In this study, we investigated the effects of chondroitin sulfate from the nose cartilage of salmon (salmon CS) on the digestion and absorption of TG, and also the antiobesity effect of salmon CS in mice with obesity induced by a high-fat diet. Salmon CS was found to inhibit the hydrolysis of TG by pancreatic lipase and also the absorption of fatty acids (one of the hydrolysates of TG), in brush border membrane vesicles prepared from rat jejunum. Mice were given free access to high-fat diets containing the salmon CS at levels of 0%, 3%, 7% and 13% for 9 weeks. Body weights were measured at one-week intervals, and parametrial adipose tissue weight, liver weight and lipid concentration, and serum lipid concentration were all measured at the end of feeding. These measured values were significantly lower in the groups fed on salmon CS at concentrations of 7% and 13% than in the high-fat diet control group. These results suggest that salmon CS suppresses obesity, fatty liver and hyperlipidemia by inhibiting the hydrolysis of TG and the intestinal absorption of fatty acids.

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The importance of indigestible carbohydrates such as dietary fiber is well recognized. In recent years, the stimulatory effects of indigestible sugars such as fructooligosaccharides (FOS) on mineral absorption have been discovered and examined. This review provides an overview of current research work in this field. FOS are not digested by human enzymes. Dietary FOS are effective for increasing not only apparent but also true intestinal calcium (Ca) absorption in rats. Dietary FOS also stimulate magnesium (Mg) and iron (Fe) absorption. These effects show dose dependency and are long-lasting. FOS increase the absorption of Mg from natural foods such as cocoa and rice bran. The increase in Ca and Mg absorption is diminished by cecectomy. Ca and Mg disappear from the colorectal contents in the course of transit from the cecum to the anus. The absorption of cecally infused Ca and Mg is increased by dietary FOS. Moreover, dietary FOS increase large intestinal calbindin-D9k. These results suggest that the stimulatory action of FOS is exerted in the large intestine. FOS improve the bioavailability of these minerals in sever disease models rats. Dietary FOS prevent osteopenia in both ovariectomized rats and gastrectomized rats. In gastrectomized rats, FOS feeding also prevents anemia. Supplying a diet with a high Ca and high phosphorus content markedly decreases Mg absorption, and rats fed such a diet exhibit typical symptoms of Mg deficiency. However, these symptoms are suppressed by FOS feeding. The Ca absorption-promoting effect of FOS has been confirmed in humans by two different methods (balance study and double isotope method). Therefore, it is expected that many clinical applications of FOS will be established in the near future.

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Thiamin-binding proteins from plant seeds are interesting storage proteins because they have dual functions: retention of thiamin in dormant seeds and provision of a nitrogen source at germination. The thiamin-binding proteins differ in molecular mass, subunit structure, amino acid composition, optimum pH for thiamin-binding activity, and binding affinity for thiamin and thiamin analogs. However, they all specifically bind free thiamin but not thiamin phosphates, which is a characteristic property of thiamin-binding proteins from plant seeds, and have a common mechanism of thiamin binding. This information suggests that the nutritive quality of seeds might be improved by using genetic engineering techniques with the genes producing thiamin-binding proteins.

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An assessment of appropriate vitamin E (VE) content in fish oil capsules was conducted from the available papers in which lipid peroxide and VE levels in human blood as indicators of VE nutritional status were determined. As a result, the minimum estimate of VE (mg of α-tocopherol equivalent) is calculated from 0.3×DBI×oil supplement intake (g), and this estimate should be doubled in practice to protect VE nutriture. When the fatty acid composition of EPA and DHA or their intake is only available, the minimum estimate is calculated from a equation, 2×{[0.3×5×EPA(g)]+[0.3×6×DHA(g)]}, and 1.5 times over this estimate should be secured in practice to sustain nutritional status of VE normal.

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