The relationship between serum ascorbic acid (AA) and diabetic macroangiopathy was studied. Fifty-six patients with noninsulin-dependent diabetes mellitus were examined, together with 20 healthy controls matched for age against the diabetes patients. Aortic pulse wave velocity (PWV) was taken as an index of the severity of atherosclerosis. The level of serum AA in diabetic patients was significantly lower than that of the controls. Among the diabetic groups, those with elevated PWV levels by age demonstrated a significant drop in AA. No significant differences were seen in the level of serum dehydroascrobic acid (DHAA) between patients and controls, nor were there any significant differences among patient groups. The concentration of serum AA was inversely related to the risk factors of atherosclerosis, such as body mass index, Apo B/Apo A-I ratio, thiobarbituric acid-reactive substances (TBARS), and microalbumin in urine. It was inferred from these findings that the depletion of serum AA was apparent in diabetics with advanced atherosclerosis.
Developmental changes in expression of α-tocopherol transfer protein (α-TTP) after birth were investigated using rats with respect to plasma changes of tocopherols. The expression of α-TTP in the neonatal rat liver, which was very low immediately after birth, increased steadily during the two weeks of life before weanling and reached the adult level at four weeks. During the suckling period, the plasma ratio of α-tocopherol to γ-tocopherol linearly increased, because plasma α-tocopherol which was low immediately after birth, increased rapidly during the period, while γ-tocopherol remained unchanged. The increase in the ratio seemed to correlate with the developmental expression of α-TTP in the liver during this period. The ratio also reached the adult level after four weeks. The expression of α-TTP was investigated using primary cultured rat hepatocytes. The expression of α-TTP was found to be extremely low after 20h of culture. The decrease in a-TTP expression was exacerbated by adding epidermal growth factor to the culture medium and was inhibited by adding dexamethasone. These observations suggest that expression of α-TTP may be affected by the state of hepatic differentiation.
Japanese salt intake is calculated through the Food Compo sition Table in the National Nutrition Survey, whereas English salt intake is through urinary sodium excretion in 24 h. This study is a comparison of salt intake between Japan and England. As different measuring methods were used in both National Nutrition Surveys, we recalculated using the same measuring method. Seven Japanese young women's sodium intakes were calculated through the Food Composition Table, and the amounts of their urinary-excreted sodium were measured. These quantities were compared, and a coefficient (87.7%) was obtained. The Japanese young women's salt intake was 9.74g/day from the Japanese National Nutrition Survey, and the coefficient was multiplied by 8.51g/day. While comparing these experimental results with English data in 1992, the English salt intake converted from sodium intake of 3, 040mg/day was 7.72g, 0.79g/day lower than the Japanese salt intake.
The main objective of this investigation was to establish the pattern in relation to time of the rat fecal endogenous nitrogen excretion by continuous feeding of balanced diets containing common peas, cowpeas or common beans as the protein sources (10% protein), labeled with 1.000 atoms % of 15N-excess. Nitrogen of endogenous origin was measured by the isotope dilution method in a 6-day experiment. Fecal excretion of endogenous nitrogen of rats fed the leguminous diets was roughly twice that of rats fed the non-protein diet (88mg, 42mg), and the excretion of total fecal nitrogen did not differ among leguminous diets. From the third to the sixth day of the experiment, the endogenous nitrogen excretion, either as a percentage or quantity (mg), attained a statistically non different value (p>0.05). A common pattern of excretion of fecal endogenous nitrogen as a function of time was expressed by a strongly negative (r<-0.95) power regression (y=A⋅x-B) for the common pea, the cowpea or the common bean diets. Conversely, the excretion of dietary nitrogen did not show a common pattern as a function of time for all experimental diets.
Graded amounts (0, 50, 500 and 5, 000mg/liter) of ascorbic acid (AsA) were given in drinking water to guinea pigs for 21 days to prepare AsA-deficient, low-AsA, moderate-AsA and excess-AsA animals, and the plasma phospholipid hydroperoxide level and lipid concentration were quantitatively determined to investigate the antioxidant effect of AsA in vivo. Phosphatidylcholine hydroperoxide (PCOOH) was a predominant phospholipid hydroperoxide present in the plasma, and the PCOOH concentration was significantly higher in AsA-deficient, lowAsA and excess-AsA animals (80.4nM, 54.8nM and 42.2nM, respectively) as compared with that in moderate-AsA animals (27.2nM). Hyperlipidemic plasma characterized as high cholesterol and high triacylglycerol concentrations was confirmed in AsA-deficient animals. Molar ratios of plasma AsA and a-tocopherol against 104 moles of phospholipids were significantly lower in AsA-deficient and low-AsA animals (0.6-2.1 and 5.5-8.5, respectively) than in moderate-AsA and excess-AsA animals (14.2-18.0 and 11.2-11.9, respectively). In plasma, a high correlation coefficient (r=0.979) was observed between PCOOH and AsA for which there was optimum AsA level to keep the low PCOOH and such correlation was stronger than that (r=0.558) observed with α-tocopherol. The results indicated that AsA has an important function to control the phospholipid hydroperoxide level in plasma and that moderate supplementation of AsA is required to reveal its optimal antioxidant effect in vivo. The present study also showed that AsA-deficiency especially invites an increase in plasma PCOOH together with a hyperlipidemic state which are risk factors in developing atherogenesis.
Soybean transphosphatidylated phosphatidylserine (SBtPS) was prepared from soybean phosphatidylcholine by transphosphatidylation using phospholipase D, and the fatty acids composition and pharmacological properties were compared with those of bovine brain cortex-derived phosphatidylserine (BC-PS) which was reported to improve cognitive disorders of senile dementia patients by oral administration (300mg/day). The molecular species of SB-tPS are rich in linoleic and palmitic acids whereas those of BC-PS are stearic and oleic acids. Despite the differences in fatty acid composition, SB-tPS displayed significant activities on the increase in brain glucose concentrations in mice (79mg/kg, i.v.) and the restoration of scopolamine-induced amnesia in rats (60mg/kg, i.p.) as did BC-PS. These results suggest the possibility that SB-tPS may prevent and/or improve senile dementia by oral administration.
The purpose of this study was to investigate the effect of ovariectomy on osteoinductive activity in the bone in rat. Homograft implantation of decalcified humeral diaphysis from ovariectomized or sham-operated rats was performed and harvested after several time periods. A significant decrease in bone induction was found in terms of soft X-ray photography, alkaline phosphatase activity, mineral content and expression of osteocalcin (BGP; bone gla-protein) in the implants from the ovariectomized group in comparison to those from the sham-operated animals. This result suggested that the level of osteoinductive activity, probably due to bone morphogenetic protein, decreased in ovariectomized animals.
We examined the effects of isomaltulose-based oligomers (IBOs) on the mineral content of the whole blood, kidney, liver and tibia in calcium deficient and calcium sufficient rats. Twenty-eight Wistar rats were divided equally into 4 grups and fed with the following diets ad libitum for 4 weeks: (1) calcium sufficient diet (Ca+, IBOs-), (2) calcium-sufficient-IBOs supply diet (Cad, IBOs+), (3) calciumdeficient diet (Ca-, IBOs), (4) calcium-deficient-IBOs supply diet (Ca-, IBOs+). There were no significant differences in final body weights among the groups. Food consumption in the calcium-deficient groups was higher than that in the calcium-sufficient groups. The tibia weight was significantly decreased, and the calcium, magnesium and phosphorous contents were significantly decreased, and iron content was significantly increased in the tibia of calcium-deficient rats. On the other hand, in IBOs feeding rats, tibia weight, and calcium, magnesium and phosphorous contents were significantly increased, and iron content was significantly decreased. These findings suggest that IBOs feeding improves mineral retention especially in a state of calcium deficiency.