Serum levels of coenzyme Q10 (CoQ10) as well as lipids weredetermined in patients during total parenteral nutrition (TPN). The mean CoQ10 levels (M±SD) were 0.77±0.30μg/ml for 108 normal subjects and 0.59±0.35μg/ml for 95 patients before TPN. The mean CoQ10 level of the patients decreased significantly to 0.35±0.23μg/ml one week after the start of TPN, and then remained almost unchanged during TPN for up to 6 weeks. When the patients receiving TPN (TPN patients) were grouped according to their clinical diagnoses, the mean CoQ10 level of patients with cancer was significantly lower than that of the other patients without cancer in 4 week therapy, but there was no difference in the levels between the patients with and without diseases of the gastrointestinal tract. Serum levels of total cholesterol (T-Chol) and esterified cholesterol in TPN patients also declined below their respective normal ranges, but not to the same extent in comparison to CoQ10. The levels of triglycerides (TG), phospholipids (PL), non-esterified fatty acids, low density lipoproteins, very low density lipoproteins, chylomicrons, and cholesterol in the high density lipoprotein fraction in serum of TPN patients were within their normal ranges. The levels of CoQ10 in TPN patients were correlative to those of T-Chol, TG, and PL, and decreased rapidly prior to the latter levels.
A high-performance liquid chromatographic (HPLC) meth-od for simultaneous determination of 7-dehydrocholesterol (7-DHC), vitamin D3 and 25-hydroxyvitamin D3 (25-OH-D3) in tissues of fishes was established, and using this method the tissue distribution of the sterols in lamprey (Entosphenus japonicus), great blue shark (Prionace glauca), skipjack (Katsuwonus pelamis) and albacore (Thunnus alalunga) was in-vestigated. The results are summarized in the following: 1) Although the alimentary canal, gall bladder and roe of lamprey and the alimentary canal of great blue shark contained comparatively high levels of 7-DHC (higher than 2, 000ng/wet tissue g), the other tissues of lamprey and great blue shark and all tissues of skipjack and albacore contained only low levels of 7-DHC (lower than 1, 000 ng/g). There was no significant correlation between the levels of 7-DHC and vitamin D3. 2) The contents of 7-DHC in the skin of skipjack and albacore were only 1/1, 000 of those in the skin of rats. 3) Although the contents of vitamin D3 in the liver of skipjack and albacore were extremely high (41, 240 and 21, 000ng/g, respectively), those in the skin were very low (454 and 257ng/g, re-spectively). 4) 25-OH-D3 was detected in the viscera of skipjack, but the levels were not very high (lower than 150ng/g). These levels were not significantly correlated with those of vitamin D3. The results suggest that large quantities of vitamin D3 in the liver of skipjack and albacore are supplied by other biosynthetic routes or by intake of vitamin D3 rather than by photochemical biosynthesis.
Increased synthesis of ornithine aminotransferase [EC 2. 6. 1. 13] (OAT) in the kidney of pyridoxine-deficient rats has been reported previously (Ikeda, M. and Okada, M. (1985): J. Nutr. Sci. Vitaminol., 31, 553-561). In this report the effects of 3, 3', 5'-triiodothy-ronine (T3) and estradiol on OAT activity in the kidney of rats given pyridoxine-deficient and control diets were studied. T3 induced renal OAT activity in rats given the control diet but not in those given the pyridoxine-deficient diet. On the other hand, estradiol induced renal OAT activity in both deficient and control rats, the levels induced in the two groups being the same. Maximal induction of OAT occurred at a lower dose of estradiol in pyridoxine-deficient rats than in the controls. When rats fed on pyridoxine-deficient diet were pretreated with pyridoxine for several days, OAT induction by estradiol was suppressed. Thus pyridoxal phosphate (PLP) may modulate OAT activity in rat kidney through the action of estradiol.
A novel procedure was developed for rapid separation of the three component enzymes of pig heart 2-oxoglutarate dehydrogenase complex by high performance liquid chromatography on a gel filtration column. The complex was dissociated and separated into two fractions of the first dihydrolipoamide succinyltransferase and a second yellow frac-tion within 1h by chromatography on a preparative TSK-GEL G4000SW column equilibrated with 0.05M potassium phosphate buffer (pH 7.0) containing 0.7M guanidine hydrochloride, 0.05% Triton X-100 and 2mM dithiothreitol at 10°C. The dihydrolipoamide succinyltransferase fraction was further purified by incubation with 0.5% sodium deoxycholate and subsequent ammonium sulfate fractionation. The other two component enzymes, 2-oxoglutarate dehydrogenase and lipoamide dehydrogenase were separated from the second yellow fraction by chromatography on a calcium phosphate gel-cellulose column. The TSK-GEL column permitted very rapid dissociation and separation of the three component enzymes accompanied by good preservation of their activities and high overall yields.
The effects of vitamin E deficiency on pituitary-gonadal function in rats and the preventive effects of N, N'-diphenyl p-phenylene diamine (DPPD) administration were examined by measuring levels of pituitary and plasma follicle-stimulating hormone (FSH) and luteinizing hormone (LH), serum and testicular levels of testosterone, and affinity and receptor sites of FSH and LH in the testis by radioimmunoassay, at 180 days after feeding of a vitamin E-deficient diet and DPPD-administered diet. Light and electron microscopic examinations were also performed on the pituitary gland and testis. In the vitamin E-deficient rats, serum and liver a-tocopherol concen-trations decreased significantly and erythrocyte hemolytic rate and serum and tissue malondialdehyde levels increased significantly. However, the increase of hemolytic rate and malondialdehyde concentration in the vitamin E-deficient rats was somewhat lessened by the administration of DPPD. In the vitamin E-deficient rats, the gonadotropic cells in the pituitary gland manifested accelerated secretory function indicated by enlargement of cells, development of Golgi apparatus and accumulation of secretory granules, while FSH and LH concentrations in the pituitary and serum were not affected by vitamin E deficiency. However, the testosterone concentrations in the plasma and testis were significantly lower in the vitamin E-deficient rats. The decrease of testosterone in plasma and tissue was prevented by the administration of DPPD, while the degeneration of seminiferous tubules was not completely restored by DPPD. It is con-cluded that DPPD can compensate to some degree for the lack of antioxidative activity due to vitamin E deficiency.
Lysozyme was reacted with xylose, methyl linoleate, gly-oxal, methylglyoxal and diacetyl in an aqueous system (50°C, pH 6.0), and browning, polymerization, changes of amino acids composition and relative digestibility of the browned lysozyme were investigated. Browning intensity as well as degree of polymerization of lysozyme in the reaction with α-dicarbonyls was higher than with xylose or methyl linoleate. After 10 days of reaction with α-dicarbonyls, the amino acid composition of lysozyme was markedly affected; i.e., 30-70% of lysine, 40-50% of tryptophan and 90% of arginine were lost respectively. By digestion with a pepsin-pancreatin system, it was observed that the relative digestibility of lysozyme reacted with dicarbonyl was lower than that of lysozyme reacted with methyl linoleate or xylose.
A casein phosphopeptide (CPP) was prepared from β-casein of cow's milk and the effect of this peptide on the absorption of calcium from a ligated segment of rat small intestine was investigated. CPP injected into a ligated loop of rat small intestine enhanced absorption of calcium from the loop and augmented the deposition of calcium in the femur. Furthermore, CPP inhibited the precipitation of calcium phos-phate in vitro, suggesting that this peptide enhances calcium absorption from the small intestinal lumen by increasing the concentration of soluble calcium. This new evidence confirms our previous hypothesis that CPP is an important factor in raising the availability of calcium in milk.
It was proved that the canavanine present during germi-nation of alfalfa both in the dark and in the light does not decrease and in fact increases a little, despite earlier papers having described the disap-pearance of canavanine during germination of alfalfa (1, 2). The presence of canavanine in alfalfa sprouts was confirmed by isolation and compar-ison with an authentic specimen. Deaminocanavanine was also isolated from both seeds and sprouts of alfalfa, but it is not clear whether this canavanine derivative is a natural product or an artifact formed from canavanine during isolation procedures.
To detect the effective substance accelerating the convertion of branched chain α-keto acids (BCKA) to corresponding amino acids, some sugars, sugar alcohols, ethanol, octanoate and ATP were tested with intravenous injection of three BCKA to rats. Plasma leucine levels 30 min after BCKA injection in rats, which were infused with 2M solution of fructose or sorbitol, reached the significantly high peak corresponding to 860% and 790% of the basal levels. Administration of ethanol (2 or 3.5M) or octanoate (4.5mM) also resulted in significantly high levels of leucine in plasma following BCKA injection as compared with control. Molar ratio of plasma branched chain amino acid (BCAA)/aromatic amino acid 30min after BCKA injection increased to 12.9 in control rats. The ratios 60 and 120min after BCKA administration were significantly higher in rats treated with ethanol (3.5M) or octanoate (4.5mM) than those in control. These results suggest that infusion of the metabolites inducing high NADH/NAD ratio in their metabolic pathways results in inhibition of BCKA decarboxylation and, as a result, enhancement of transami-nation of BCKA into BCAA.
The bioavailability of newly developed sugar substitutes was observed by measuring the transmural potential difference (APD) evoked by Na+ -dependent active trasport of glucose, which is supposed to be produced by the hydrolysis of sugar substitutes. ΔPD was measured using everted intestinal sac prepared from jejunum of adult rats and compared with the digestibility of sugar substitutes in the mucosal homogenate of everted sac. ΔPDs evoked by glucose, maltose or maltosylfructose had almost the same levels, however, the ΔPD evoked by sucrose was a little lower. ΔPDs evoked by maltitol or palatinose were low, and ΔPDs evoked by fructo-oligosaccharides were negligible. The hydrolyzing activities of these sugars and sugar substitutes by the mucosal homogenate were correlated with the ΔPDs. A significant positive correlation was observed between ΔPDmax of various sugars and sugar substitutes and the Vmax of their corresponding hydrolyzing activities. Also, a significant positive cor-relation was observed between Kt and Km values of these sugars. These results suggest that the absorption of sugar substitutes is dependent on digestibility by membrane digestive enzymes.
The present study was undertaken to provide further evid-ence for mechanisms proposed for the toxicity of ingested winged bean lectin in animals: to determine its effect on activities of some hydrolases localized in the brush border membrane of the small intestine. An adaptive increase in sucrase activity of rats given a high-sucrose diet (HSD) was restrained by the addition to HSD of a lectin fraction (WBLF) isolated from raw winged beans but not by that of heated WBLF or soybean trypsin inhibitor. Restraining effects of WBLF added to HSD on time-course changes in activities of sucrase, alkaline phosphatase and leucine aminopeptidase of rats after giving HSD were similar to those of concanavalin A, which had been observed in the previous study. These results substantiate that the mechanism of the toxicity of ingested winged bean lectin involves its binding to the luminal surface of the small intestine and in turn disturbing the functional formation of the brush border membrane.
The influence of the chronic intake of a newly developed sweetener named “Neosugar” (fructooligosaccharide) on body weight gain, organ weight, serum lipids, fecal excretion and intestinal function was investigated in rats. The following results were obtained. 1) Body weight gain was diminished more severely in rats fed on 20% Neosugar diet than in rats fed on 10% Neosugar diet. 2) The wet weights of cecum and colon were greatly increased by Neosugar feeding. 3) Fecal wet weight was significantly increased and gastrointestinal transit time was shortened by Neosugar feeding compared with those of the control group. 4) Serum triacylglycerol levels were significantly lower in rats fed Neosugar, whereas serum cholesterol levels were similar to those of the control group. 5) Fecal excretions of neutral sterol and volatile fatty acids were significantly increased by Neosugar feeding. These results were quite similar, with the exception of diarrhea to those obtained using a dietary fiber such as glucomannan. Therefore, Neosugar with a pleasant-tasting sweetness appears to be an unavailable oligosaccharide with a dietary-fiber-like action.
The effect of L-methionine supplementation on the utili-zation of a soy protein isolate (SPI) was evaluated by short-term nitrogen balance studies in young women. Thirteen female students were given SPI in an initial period and SPI supplemented with 1% methionine in a second period immediately after menstruation as the sole source of pro-tein. After one day on protein-free diet, each subject received conven-tional low-protein diet for three days, and then low protein, semisyn-thetic diet containing 0.5g/kg/day (seven subjects) or 0.3g/kg/day (six subjects) of SPI or SPI supplemented with methionine for seven days. The energy intake was approximately of a maintenance level of 36.5±3.8 kcal/kg/day. The mean N balances of the subjects at an intake level of 0.5g/kg/day in the SPI period and methionine supplemented period were -6.2±12.6 mg N/kg and -9.8±9.8mg N/kg, respectively, while their N balances at an intake level of 0.3g/kg/day were -17.8±7.2mg N/kg in the SPI period and -15.5±3.0mg N/kg in the methionine supplemented period. There was no significant difference between the values in the SPI and methionine supplemented periods at both levels of protein intake. Blood analyses were carried out before and after the SPI period and after the period of methionine supplementation. The urinary creatinine and urea excretions during these periods were not markedly affected.
The following five spices were pasteurized with superheat-ed steam, as given in parentheses: origanum (1 kg/cm2, 132°C, 3.5 sec), laurel (0.5kg/cm2, 118°C, 3.5 sec), turmeric (2 kg/cm2, 160°C, 5 sec), coriander (1kg/cm2, 140°C, 5 sec), and aniseed (1kg/cm2, 140°C 5 sec). The detected tocopherols and other constituents were as follows: orig-anum (α-, β-, γ-, δ-), laurel (α-, β-), turmeric (so little that no comparison could be made), coriander (almost no tocopherols), and aniseed (α-, β-, δ-). The tocopherols and unsaturated fatty acid constituents of origanum, laurel, aniseed and coriander underwent little change after pasteurization with superheated steam, indicating stability, which may be due to the synergistic effect of tocopherols and phenolic compounds present in these spices.