The aim of this work was to study the relationship between body ascorbic acid (AA) status and serum lipid profile and ferritin concentrations in healthy pre- and postmenopausal women. The mean leukocyte and plasma ascorbate values in postmenopausal women were found to be significantly low but within acceptable ranges as compared to premenopausal women. According to these results, plasma and leukocyte AA concentrations decreased after the cessation of ovarian hormone production. In addition, significant increases in total cholesterol, tri-glyceride and LDL-cholesterol but a significant decrease in HDL-cho-lesterol were observed in postmenopausal women as compared to pre-menopausal women. A close positive relationship was found between plasma and leukocyte AA and body iron status in postmenopausal women. The findings were prominent especially in the subgroup of postmenopausal women with low body AA status. Thus, it is concluded that women having low body AA concentrations might have a predispo-sition for iron depletion.
The hypoglycemic effect of To-Kai-San (TS) was studied in normal mice, streptozotocin-induced diabetic mice, one of the animal models of insulin-dependent diabetes mellitus (IDDM) with hypoinsulin-emia, and KK-Ay mice, one of the animal models of non-insulin-dependent diabetes mellitus (NIDDM) with hyperinsulinemia. TS (1, 500mg/kg) reduced the blood glucose of the KK-Ay mice from 441±36 to 285±52 mgt 100ml 7 h after a single oral administration (p<0.001). However, no changes in blood glucose were observed in the normal and STZ-induced diabetic mice. TS also decreased the blood glucose 20 days after repeated administration to normal and KK-Ay mice. In addition, TS-treated KK-Ay mice showed decreased plasma insulin levels after both single and repeated administration. From these findings, it is believed that TS may require the presence of insulin to display its activity.
Monoesters with the ester groups at C-2 of pyrroloquinol-ine quinone (PQQ) and C-9 of imidazopyrroloquinoline (IPQ) were synthesized, and radical scavenging activities of coenzyme PQQ, IPQ compounds synthesized from PQQ and various amino acids, and mono-esters of PQQ and IPQ were studied in vitro and in vivo. PQQ and PQQ monoesters had strong radical scavenging activity using ESR in in vitro experiments. The ICso value for superoxide (02-) was from 1 to 6×10-8M and that for the hydroxy radical ('OH) was from 4 to 6×10-5M. IPQ compounds and IPQ monoesters also showed radical scavenging activity. These compounds prevented injury during in vivo experiments, such as hydrocortisone-induced cataracts, endotoxin shock and CCl4-induced liver injury (isolated hepatocytes and rats). Especially, the monoesters of PQQ and IPQ prevented liver injury in rats equally by oral or intra-peritoneal administration. These results suggest that PQQ functions as a radical scavenging factor in addition to being a cofactor of quinoprotein enzymes, and monoesters with the ester groups at C-2 of PQQ and C-9 of IPQ are developed as treatment or preventive medicine for disease caused by radical compounds on the basis of strong radical scavenging activities, absorbability into cells, toxicity, safety and chemical stability.
This study was conducted to evaluate the ability of the large intestine to absorb calcium (Ca) and magnesium (Mg) from their sparingly water-soluble salts, and also to determine whether fructooligo-saccharides (FOS) stimulate the absorption of these minerals in rat large intestine in vivo. Rats were fed Ca- and Mg-free diets with and without 5% FOS. An aqueous suspension of CaCO3 and MgO was infused into the stomach via a gastric tube or into the cecum via an implanted catheter. Coprophagy was prevented by using wire-mesh anal cups throughout the experiment so as to exclude the re-ingestion of feces as an oral mineral source. In rats fed an FOS-free diet, the absorption degrees of Ca and Mg infused into the cecum were the same as those infused into the stomach. The absorption degree of phosphorus (P) was slightly but significantly higher in rats with the infusion of Ca and Mg into the cecum than in rats with the infusion of Ca and Mg into the stomach. FOS-feeding increased the absorption of Mg to a similar extent in either case of infusion via cecal and oral routes, while FOS-feeding did not increase the absorption of Ca in rats with infusion of Ca and Mg into the cecum. We concluded that both CaCO3 and MgO are absorbed in the large intestine, and we ascertained that the increasing effect of FOS on the absorption of Mg took place mainly in the large intestine.
The purpose of this study was to characterize the lipopro-tein and apoprotein profiles of hyperlipidemic atherosclerosis-prone (HAP) Japanese quail. HAP and commercially available (CA) Japanese quail were fed either a semi-purified diet containing 1% cholesterol or a cholesterol-free diet for two weeks. The lipoproteins of CA and HAP quail fed cholesterol-free diet were composed of two fractions: densities ranging from 1.02 to 1.09 and from 1.09 to 1.21. The lipoprotein distri-bution patterns obtained from both strains showed an HDL-predominant pattern. A protein of 26 kDa was the major apoprotein in the entire density range of the lipoprotein class. Marked increases in the cholesterol ester levels were observed in the lower density fractions (1.006<d<1.055: chylomicron and VLDL fractions) of the cholesterol-fed quail, accounting for 46% of the total lipids in CA quail and 54% in HAP quail. In addition, the presence of a protein of 470 kDa was exclusively observed in the lower density fractions (1.006<d<1.055) of the cholesterol-fed HAP quail. The fatty-acid compositions of the chylomicron and VLDL fractions were affected by the dietary cholesterol in both strains: a decrease in concentration of 16:0 and increase in 18:0 (weight%). However, cholesterol feeding had no effect on the level of cholesterol, chemical composition or fatty-acid composition of the HDL fractions in either strain. Although the lipoprotein and apoprotein profiles of HAP quail showed resemblances to those of the CA quail, expression of the 470 kDa protein in the lipoproteins (d<1.055) appeared to be pronounced in HAP quail. The relevance of these lipoprotein and apoprotein profiles to the genesis of atherosclerosis was discussed in this study.
The sufficiency of the dietary protein allowances recom-mended by the Ministry of Health and Welfare of Japan for various physical exercises has not been examined. We investigated the protein requirement for moderate-intensity physical exercise using nitrogen bal-ance in the isoenergetic state. Seventeen healthy college students exer-cised for 10 days with an adaptation period of three days and non-exercise control period of 10 days. They were given a maintenance level of energy and 1.08g/kg per day of high quality mixed proteins recommended by the Ministry of Health and Welfare of Japan throughout the experimental period. They performed treadmill running during the exercise period at about 65% of VO2max for 25, 41 or 48min/day, which required 200, 300 or 400 kcal of extra energy, respectively. Although the exercise increased dermal nitrogen loss, urinary nitrogen excretion tended to decrease. Consequently, the exercise ranging from 200 to 400 kcal/day did not significantly alter the nitrogen balance. Thiobarbituric acid-reactive substances and glutathione disulfide were not increased after exercise, suggesting that the moderate exercise, recommended for health promo-tion by the Ministry of Health and Welfare of Japan, does not cause oxidative damage to healthy subjects. These findings demonstrate that a protein intake of 1.08g/kg per day is enough for moderate exercise.
For the maintenance of good health of very old people such as centenarians, nutrition is very important. However, the information on their nutritional status is very limited. In this study, we evaluated the nutritional status of centenarians by comparison with elderly in their 70s and ;young adults. Volunteer subjects were comprised of 71 centenarians (51 females, 20 males) who were not bed ridden, 84 elderly in their 70s (51 females, 33 males) who had no specific health problems and 27 healthy young adults in their 20s (17 females, 10 males). We compared 11 'items 'of the activities of daily living (ADL), height, weight, hemato-logical (hemoglobin, hematocrit and red blood cell count) and biochem-ical [total protein, albumin, total-, HDL-, LDL- and VLDL-cholesterols, triglycerides, glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and creatinine] variables among the three age groups. Since the atrophy of muscle is more severe than the atrophies of other tissues in the elderly, we studied the muscle protein breakdown using plasma 3-methylhistidine (3-MH) as a marker. The results of all indices except serum lipids, GOT and GPT, were lower in the centenari-ans than in the subjects in their 20s (p<0.05) and were lower than the lower reference limits. Most of the results of the elderly in their 70 s were within the reference intervals. However, as compared to the young subjects, they had: 1) normal ADL; 2) shorter height; 3) heavier weight in females and lighter weight in males; 4) lower total protein and albumin levels and albumin/globulin (A/G) ratios; and 5) higher total- and LDL-cholesterol levels in females and HDL-cholesterol levels in males (p<0.05). The plasma 3-MH concentration was higher in the centenarian group than in the young and elderly groups (p <0.05). However, serum creatinine concentrations also tended to be high in the group, suggesting that a high 3-MH concentration did not indicate accelerated muscle protein breakdown but rather poor kidney functions. The results of this study show that the centenarians had shrunken stature, low hematological values and poor protein nutrition but rather normal lipid nutrition, however the elderly subjects in their 70s could still maintain most nutri-tional parameters in relatively normal condition.
Objective: To assess the relationship between dietary lipids and incidence of cerebral infarction in a Japanese rural population. Design: A cohort study from July 1977 through December 1992. Setting: Akadani-Ijimino (A-I) district, Niigata Prefecture, Japan. Subjects and methods: All the residents, 1, 182 men and 1, 469 women, aged 40 years and over. Out of these members, 954 men and 1, 329 women who were initially free of stroke completed a semiquantitative food frequency ques-tionnaire in 1977, and were then subjected to a follow-up for 15.5 years. The occurrence of stroke was determined by the annual follow-up exam-ination and registry. Dietary lipid was adjusted for total energy or fat intake by the residual method. Sex- and age-stratified and blood pressure-and atrial fibrillation-adjusted relative risk for cerebral infarction was estimated by the Cox proportional hazard model. Results: There were 75 new cases of cerebral infarction during the observation period. The relative risk for cerebral infarction was less than one in the highest quartile level of total fat, saturated fatty acids (S), Keys score and west-ernized dietary pattern: 0.68-0.94. It ranged between 1.36 and 1.57 in the highest level of polyunsaturated (P), n-3 and n-6 fatty acids, and P/S ratio. Conclusion: This study suggests the possibility that the traditional Japanese diet, very low fat intake, was likely to increase the risk of stroke through the low level of serum cholesterol as an intermediary factor.
Endogenous factors responsible for the textural character-istics of buckwheat products were studied. An analysis with various buckwheat samples showed that there were variations in protein, starch, amylose and amylopectin contents among the various buckwheat flours examined. The protein contents of the buckwheat flours were significantly negatively-correlated to the starch, amylose and amylopectin contents of buckwheat. A texturometric analysis showed that the springiness of heated-dough made from buckwheat flour was positively correlated to its starch content and amylopectin content, and the springiness and chewi-ness was negatively correlated to the protein content. Experiments adding isolated buckwheat protein or starch to buckwheat dough confirmed the above-mentioned correlation between texture and components. This study suggests that both the protein and starch present in buckwheat flour may be important factors responsible for the textural characteristics of buckwheat products.
This study was performed to investigate whether the long-term feeding of a high vitamin E (VE) . diet has a beneficial effect on the decreased cellular immune functions caused by aging. Male Fisher rats, 12 weeks old, were fed a regular (50mg VE/kg diet) or high VE diet (585mg VE/kg diet) for 12 months. Then, the rats were sacrificed under anesthesia and their cellular immune functions were measured. The proliferation of splenic lymphocytes with PHA or Con A was significantly lower in old rats fed the regular diet as compared to that of young rats (two months old). In contrast, the proliferation of splenic lymphocytes in old rats fed the high VE diet was similar to that of young rats. The in vitro effect off macrophages (Mφ) on the proliferation of splenic lymphocytes from young rats was investigated under Con A stimulation. Although splenic Mφ isolated from old rats fed the regular diet did not have any effect on the proliferation of splenic lymphocytes, Mφ from old rats fed the high VE diet significantly enhanced the proliferation of splenic lym-phocytes. The responsiveness of splenic lymphocytes isolated from each group to the Mφ of young rats under Con A stimulation was not significantly different between the young rats and old rats fed the regular diet. In old rats fed the high VE diet, the responsiveness of splenic lymphocytes to young rat Mφ was significantly higher than that of the young rats or old rats fed the regular diet. Furthermore, the high VE diet induced a significant increase in interleukin 2 (IL2) production from splenocytes in both young rats and old rats following in vitro stimulation with Con A for 48 h. These results suggest that VE has the ability to improve the decreased cellular immune functions caused by aging, and appears to be associated with the enhancement of both Mφ functions and lymphocyte responsiveness.
Lactitol-oligosaccharide (LO) was prepared from lactitol by transglycosylation reaction with Aspergillus oryzae β-galactosidase. LO is resistant to metabolism in the small intestine but not in the large intestine. The effects of LO, lactose (Lac), lactitol (Lacol) and galacto-oligosaccharide (GL) on calcium and magnesium absorption were deter-mined by feeding 8-week-old Sprague-Dawley male rats diets containing 5% of the above carbohydrates for two weeks. The results obtained were as follows. 1) A significant increase of calcium absorption was observed in the LO diet. 2) A significant increase of magnesium absorption was observed in the LO, GL and Lacol diets. 3) The concentration of total volatile fatty acids (VFA) in the cecal contents increased significantly in the LO, GL and Lacol diets. The main constituent of VFA in the cecal contents was found to be acetic acid. 4) The correlations between calcium and magnesium absorption ratios and total VFA concentration in the cecum were found to be significantly related. These findings suggest that LO is metabolized to VFA, among which acetic acid concentration seems to have the most stimulatory effect on the absorption of calcium.
The distributions of phylloquinone (PK) and menaqui-none-4 (MK-4) in various tissues were assessed after the oral administra-tion of phylloquinone. Wistar rats were fed a vitamin-K-deficient diet for nine days, fasted for 24 h and then given phylloquinone orally at 4 mg/kg body weight. Rats were sacrificed 0, 6, 12 and 24 h after the administra-tion, and an analysis was made of the vitamin K analogues in the plasma, liver, brain, testis, kidney and spleen. The phylloquinone concentration in plasma and the tissues reached a peak 6 h after the oral administration of phylloquinone. By contrast, the concentration of MK-4 peaked in the liver, plasma, kidney and spleen at 12 h, and in brain and testis at 24 h. This data suggests that the ingested phylloquinone was probably con-verted into MK-4 within the tissues themselves, rather than via hepatic metabolism. The evidence for this is that, after phylloquinone administra-tion, (i) in each of the tissues, the MK-4 concentration increased much more slowly than that of phylloquinone, and (ii) the MK-4 concentration in the plasma and liver reached only much lower levels than those seen in other tissues.
Barley hordein was comparable to maize zein in antioxida-tion under a powder model system. Various deamidated “hordein” preparations were obtained and examined for their molecular-size distri-bution (by Sephacryl S-loo gel filtration), hydrophobicity (by fluores-cence measurement using fluorescent probes) and antioxidative activity (by the ferric thiocyanate method). Deamidation caused fragmentation of the hordein molecule and simultaneously lowered its fatty acid-binding capacity rather than its surface hydrophobicity. Then, the antioxidative activity diminished with increasing deamidation. When the fatty acid-binding capacity was plotted against the antioxidative activity, a high correlation (r2=0.92) was observed between these two events.
This work describes the long-term effects of two different diets, one rich in olive oil and the other in sunflower oil, on serum lipid and lipoprotein levels after the establishment of fatty liver in rats 8 and 15 months old. The serum lipid and lipoprotein levels as well as the steatotic process have been evaluated by biochemical and histological methods, respectively. The results showed that fatty liver was well developed with both long-term high-fat diets, and hepatocytes were filled with many lipid droplets. This process was more evident in the portal zones, where fat hepatocytes were more numerous. Serum total cholesterol (TC) and HDL-C levels were highest in the sunflower oil fed rats, whereas the TG and LDL-C levels were highest in the olive oil group. Finally, the atherogenic indexes (HDL/TC, HDL/LDL, HDL/(TC-HDL)) were higher in the sunflower oil diet group than in the olive oil group.
Feed efficiency in rats fed a low soybean protein isolate (SPI) diet (100g/kg diet) was dramatically improved with the supplemen-tation of L-methionine (3g/kg, diet). Pancreatic amylase activity was low in rats fed a low SPI diet, and was much higher in the supplemented group than in the non-supplemented group. Pancreatic trypsinogen and chymo-trypsinogen contents (as activities of trypsin and chymotrypsin) were not changed with the methionine supplementation. In the small intestine, sucrase and leucine aminopeptidase in the jejunum and ileum were not clearly changed. In conclusion, a small amount of methionine supple-mented to a low SPI diet especially induced pancreatic amylase among digestive enzymes. The factor involved in nutritional status, not the physiological action of methionine itself, may contribute the induction of amylase.