The effect of extracts from Hovenia dulcis Thunb. on alcohol (ethanol) concentration after administration of alcohol to rats and men were examined. When a fraction (Fr. G, 0.5g/kg b. w.) extracted from H. dulcis was administered orally to rats 5min before oral administration of alcohol (2g/kg b. w.), the percentage decreases in maximum blood alcohol and acetaldehyde levels were 40% and 37%, respectively, the decreases being larger than those induced by other fractions from H. dulcis. On the other hand, when ethanol extract (0.125g/kg b. w.) was administered orally to men 20min before oral administration of alcohol (0.3g/kg b. w.), decreases in alcohol and acetaldehyde concentrations in saliva were observed, and the expiratory alcohol concentration at 1h after drinking beer was significantly decreased in five men out of eight
Female Wistar rats which had been fed a diet containing soy bean oil (soya) for 4 weeks before mating were divided into two dietary groups after delivery: half of the rats were fed a diet supplemented with docosahexaenoic acid ethyl ester (DHA), and the other half were kept on the soy bean oil diet. Weaned rats were fed the same diet that had been given to their mothers. The fatty acid composition of milk obtained from the stomachs of pups, and also that of the liver and cerebral cortex was analyzed. During lactation, the DHA level in milk was higher in the DHA group than in the soya group. The DHA levels in both the liver and cerebral cortex were also higher in the DHA group than in the soya group. However, the DHA levels in the cerebral cortex of the two groups were approximately the same in both weaned and adult rats. DHA intake was more effective in elevating the concentration of DHA in the liver and cerebral cortex of suckling pups than in weanling pups.
A study was conducted to examine the effects of dietary undigestible oligosaccharides on the development of galactosamine hepatitis in rats. Four-week-old Wistar rats (weight: 55-70g) were fed diets containing 10% oligosaccharides or monosaccharide besides the standard diet for two weeks after one week of prefeeding with the standard diet. On the last day of feeding, the rats were intraperitoneally injected with D-galactosamine solution (800mg/kg body weight), and 20h later the activities of some plasma enzymes were determined to evaluate the effects of oligosaccharides on the development of galactosamine hepatitis. In the first experiment, lactulose, fructooligosaccharide, gentiooligosaccharide, maltooligosaccharide, glucomannooligosaccharide and galactooligosaccharide (T) ((Gal) n-β- (1→6) -Gal-β- (1→4) -Glc) were used. As a result, all of the activities of plasma glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase and lactate dehydrogenase in the lackulose group tended to be lower than in the cont ol group, and those in the galactooligosaccharide (T) group were significantly lower than in the other groups. Thus it is considered that the development of galactosamine hepatitis is depressed by dietary galactooligosaccharide (T). However, maltooligosaccharide and glucomannooligosaccharide were shown to have no effect. The results of the second experiment indicated that the development of galactosamine hepatitis is depressed not only by lactulose, raffinose and galactooligosaccharide (B) ((Gal) n-β- (1→4) -Gal-β- (1→4) -Glc) but also by digestible saccharides such as lactose and galactose in the diet.
As part of a basic study on the prevention of ischemic cerebral injury, sesamin (5g/kg Funabashi SP diet) was administered to stroke-prone spontaneously hypertensive rats (SHRSP) for 8 weeks from 8 weeks of age, and pathological and biochemical changes in the cerebral cortex were examined and compared with those in normotensive Wistar-Kyoto rats (WKY). In the control SHRSP, cerebral softening was found in 4 of 8 rats (50%), whereas no pathological changes were evident in sesamin-treated rats. In control SHRSP, the uric acid content of the cerebral cortex was extremely high in comparison with that in control WKY, but it was significantly lower (p<0.05) in sesamin-treated SHRSP. On the other hand, superoxide dismutase (SOD) activity was lower (p<0.05) and Na/K-ATPase was higher (p<0.05) in sesamin-treated SHRSP than in WKY. These results indicate that lipid peroxidation caused by free radicals is an important factor in ischemic cerebral injury, and that sesamin plays an important role in the scavenging of free radicals, thus preventing cerebral softening in SHRSP.
Casein phosphopeptides (CPP) enhance the absorption of calcium (Ca) by inhibiting the precipitation of calcium phosphate in vitro, although the effect on in vivo balance is controversial. This study was undertaken to determine the utilization of Ca and phosphorus (P) from CPP itself in growing male and female rats. CPP prepared from a tryptic hydrolysate of whole casein was added to a test diet, 80% of dietary Ca and 100% of dietary P being supplied as CPP. The dietary Ca and P levels were 5g/kg and 4g/kg, respectively. During the 23-day feeding period, a mineral balance study was carried out from days 19 to 22. The apparent Ca, P and magnesium (Mg) absorption rate, and Ca and P retention in the male rats fed the CPP diet were significantly higher than the equivalent values in the male rats fed with control diet (p<0.05). There was no significant difference in apparent Mg retention among the male groups. The apparent P absorption rate, P retention, and Mg absorption rate in the female rats fed the CPP diet w re significantly higher than the equivalent values in the female rats fed the control diet (p<0.05). There was no significant difference in the apparent Ca absorption rate, Ca retention, and Mg retention among the female groups. No significant difference was observed between the CPP diet group and the control diet group with regard to the mineral contents of the serum and kidney. It is suggested that Ca and P from CPP could be well utilized in growing rats.
From 5 to 20 weeks of age, stroke-prone spontaneously hypertensive rats (SHRSP) were fed a diet, containing dry Euglena cells (Euglena gracilis Z: at 30.4% in diet) as a protein source (Euglena diet) and its effects on the activity of angiotensin I-converting enzyme (ACE) in serum and vascular tissues and on the aortic elastin content were studied. The effects of captopril, an ACE inhibitor, were also studied for comparison. 1) The Euglena diet had no significant effect on blood pressure. In the SHRSP administered captopril from 5 weeks of age, blood pressure elevation was inhibited. 2) The serum ACE activity in SHRSP fed the Euglena diet showed no difference from that in the control group fed a commercial stock chow. In the SHRSP administered captopril, the serum ACE activity was enhanced. 3) The thoracic aorta ACE activity was lowered more (p<0.05) in both the Euglena-fed and captopril-treated groups than in the control group. The mesenteric artery ACE activ ties in both experimental groups were somewhat lower than that in the control group. 4) The ratio of aorta weight to body weight was significantly lower (p<0.05) in the Euglena-fed and captopril-treated groups than in the control group. Higher levels of aortic elastin were observed in the Euglena-fed and captopril-treated groups (p<0.05). These results suggest that suppression of hypertrophy and reduction in elasticity of the vascular wall in SHRSP fed a Euglena diet are due to an inhibitory effect on vascular tissue ACE activity.
From 5 weeks of age, stroke-prone spontaneously hypertensive rats (SHRSP) were fed a diet based on dry cells of Euglena (Euglena gracilis Z; at 25% in diet) with enriched docosahexaenoic acid (DHA-Euglena) until natural death or sacrifice at 20 weeks of age, and the effects of the diet on blood pressure, incidence of stroke lesions and life-span were examined. Spontaneous elevation of blood pressure was depressed by the DHA-Euglena diet after the start of feeding, and after 10 weeks of age the blood pressure remained constant at 210 to 230mmHg. The life-span of the DHA-Euglena-fed group was marked longer than that of the control group, and the incidence of cerebral stroke lesions was lower than that in the control rats. On the other hand, a defatted Euglena diet (at 20% in diet) exerted little effect on blood pressure, but obvious prolongation of life-span was observed. Suppression of aortic hypertrophy was recognized in SHRSP fed the DHA-Euglena diet, and a high level of aortic elastin was maintained. The activities of angiotensin I-converting enzyme (ACE) in the thoracic aorta and mesenteric artery were lower in the DHA-Euglena group than in the control group (p<0.05). The lipid peroxide (TBARS) level and activities of related enzymes in the blood of the DHA-Euglena group showed no difference from those in the control group. Prevention of blood pressure elevation, reduction of the incidence of cerebral stroke lesions and prolongation of life-span in SHRSP were more evident after feeding with DHA-Euglena than with ordinary Euglena. These results indicate that Euglena rich in DHA has an augmented suppressive effect against hypertensive disease in SHRSP.
A study was undertaken to determine the relationship between nephrocalcinosis and kidney function in rats fed a high-phosphorus diet. Young male Wistar rats with an average initial body weight of 90g were used. The supplemental level of phosphorus in a basal diet was adjusted to 0.5% or 1.5%. The rats were then fed a diet containing either level of phosphorus for 21 days. Nephrocalcinosis was determined by analysis of kidney calcium content and histological examination of kidney tissue. As indicators of kidney function, urinary volume, serum and urine creatinine, albumin and urea nitrogen and creatinine and urea clearance were examined. The renal calcium content and urinary phosphorus excretion of rats fed the 1.5% phosphorus diet were higher than those of rats fed the 0.5% phosphorus diet. Urinary creatinine, and albumin excretion, serum urea nitrogen and creatinine clearance of rats fed the 1.5% phosphorus diet were higher than those of rats fed the 0.5% phosphorus diet, but urea clearance was decreased. In kidney tissue of the rats fed the 1.5% phosphorus diet, dilatation of part of the distal tubule and almost all of the collecting tubule was observed by light microscopy, and calcium deposition was revealed by von Kossa stainning.
We prepared a mixture (SK-204, 10% in diet) consisting of dried shiitake mushroom (Lentinus edodes) treated by wet-heating and fructo-oligosaccharides (7: 3), and evaluated its action on lipid levels in rats fed a cholesterol diet for 14 days. Administration of SK-204 suppressed the increases of cholesterol and phospholipid levels in the serum, and those of total lipid, cholesterol, triglyceride and phospholipid levels in the liver. These results suggest that SK-204 can suppress the increase of lipid contents in the blood and the accumulation of lipids in the liver resulting from ingestion of cholesterol.
The gastrointestinal structure of male Sprague-Dawley rats was studied after 5 months of consecutive dietary manipulation with either fully-hydrogenated dietary canola oil (FH oil) or cellulose. A diet containing 15% cellulose was given to a control group, and for the FH oil diet cellulose was replaced with 10% FH oil. Light microscopy was used to examine the structural changes in the alimentary tract after these dietary manipulations. Food efficiency ratio, relative weight of the liver, and serum chemistry values did not differ between the two groups. No histological differences between the FH oil and control groups were observed. These results indicate that the histological changes induced by FH oil in the rat gastrointestinal tract are equivalent to those induced by cellulose.
Ume extract is a dark brown and very sour paste which is produced by boiling down fresh ume (young fruits of Prunus mume) juice. The composition of homemade ume extract was analysed with regard to free amino acids, organic acids, sugars and sugar alcohols. Fifty grams of ume extract was made from 1 kg of fresh ume. In all samples the major components were found to be malic acid and citric acid, which amounted to 40-53%. However, the molar ratio of malic acid to citric acid differed according to the time of harvest and the variety of ume. Content of free amino acids was 0.6-1% by weight, the major part of which was asparagine. The major sugars found in fresh juice were fructose, glucose and sucrose. The browning and rapid decrease in both free amino acids and sugars at the final stage of the concentration process suggested the progress of the Maillard reaction. The presence of pheophytin a was also suggested.
The antioxidative activities of wasabi (Eutrema wasabi MAXIM.) root, stem, and leaf extracts were evaluated by several methods. The wasabi stem extract was found to be a strong antioxidant when tested by the TBA method using deoxyribose as the substrate, whereas the HPTLC assay using linolenic acid as the substrate indicated that the activity of the leaf extract was greater than those of the stem and root extracts. All three extracts showed strong-OH radical scavenging activity when tested by the ESR method. Superoxide scavenging activity was extremely high in the leaf extract, whereas the stem and root extracts did not show any appreciable effect. These results suggest the occurrence of different antioxygenic principles in the leaf and stem of wasabi. As most of the wasabi leaf and stem has not been utilized so far, these findings will contribute to the total utilization of wasabi plants.