Organic solvent-soluble lipofuscin pigments and glutathione peroxidase in mouse brain and heart: effects of age and vitamin E.

The effect of age and dietary supplementation of vitamin E or N,N'-diphenyl-p-phenylenediamine (DPPD) on organic solvent-soluble lipofuscin pigments (OLP) and glutathione peroxidase (GSH-Px) activity in mouse heart and brain was investigated. Four groups of 32 female weanling mice were fed a basal diet containing either 0, 30 or 300 ppm RRR-alpha-tocopheryl acetate (d-alpha-tocopheryl acetate) or 30 ppm DPPD from 2 to 18 mo of age. Neither GSH-Px activity nor dietary supplementation of vitamin E or DPPD had an effect on OLP concentrations in the brain or heart. OLP levels were two- to fourfold higher at 12 mo of age in the heart and were lower at 18 mo of age in the brain than at 2 or 9 mo of age. GSH-Px activity increased with age in the heart tissue of vitamin E-deficient and DPPD-supplemented mice only. No change in GSH-Px activity was observed in the brain due to diet or increasing age. These results suggested that OLP concentrations were not affected by dietary supplementation of vitamin E or DPPD but were affected by age-related factors in the mouse brain and heart.

Organic solvent soluble lipofuscin pigments and glutathione peroxidase in weanling and old rats.

Tissues from weanling and 19-month-old Sprague Dawley rats were spectrophotofluorometrically analyzed for organic solvent soluble lipofuscin pigments (OLP) and assayed for glutathione peroxidase (GSH-Px) activity. Significantly lower levels of OLP and higher levels of GSH-Px activity were found in the kidney, heart and testis at 19 months of age than were found in weanling rats. No age-related differences in OLP were observed in the brain, lung or liver. The results appeared to indicate an inverse relationship between OLP and GSH-Px activity in some tissues, but the magnitude of the changes observed coupled with conflicting observations in the liver suggested that GSH-Px activity and OLP concentrations were not directly related.

Effect of dietary vitamin E upon fluorescent compounds of the rat uterus.

Several water soluble and organic solvent soluble fluorescent peaks were observed in extracts of uteri from vitamin E deficient or supplemented rats following Sephadex column chromatography and spectrophotofluorometric analysis. Levels of one of the organic and two of the water soluble fluorescent peaks were found to be significantly higher in the uteri of vitamin E deficient rats than in vitamin E supplemented rats. Some of these fluorescent fractions may contribute to the brown discoloration that is known to occur in the uterus of vitamin E deficient animals.

Ontogenetic development of L-gulonolactone oxidase activity in several vertebrates.

Activity of L-gulonolactone oxidase (EC 1.1.3.8) in livers of fetal Rattus norvegicus and Mus musculus was detectable on the 18th day of gestation, increased rapidly to maxima at 15 and 5 days postpartum for the two species, respectively, and thereafter declined to adult levels. L-Gulonolactone oxidase was not detectable in liver or kidney of fetal guinea pigs at any stage of development. Near-term fetal snowshoe hares had higher activities of liver L-gulonolactone oxidase than observed in a large sample of adults. L-Gulonolactone oxidase was detectable in chicken (Gallus gallus) embryos by the sixth day of incubation, increased rapidly in the kidney with no discontinuity at hatching, reached a maximum at about the 35th day from the beginning of incubation, and then declined to adult levels. Barn swallow (Hirundo rustica) embryos appeared to synthesize little if any L-ascorbic acid; nestlings had considerably higher levels of L-gulonolactone oxidase than adults. Tadpoles of three species of frogs had appreciable levels of L-gulonolactone oxidase activity.

Long-term NO2 exposure of mice in the presence and absence of vitamin E. II. Effect of glutathione peroxidase.

One hundred and twenty female mice fed diets containing various levels of vitamin E were continuously exposed to 0.5 ppm, 1.0 ppm nitrogen dioxide (NO2), and filtered air for 17 months. Blood, lung, and liver tissues were assayed for glutathione peroxidase (GSH-peroxidase) activity. Exposure to 0.5 ppm NO2 did not affect blood and lung GSH-peroxidase activity; 1.0 ppm NO2 exposure, however, caused suppression of the enzyme. A combination of vitamin E deficiency and 1.0 ppm NO2 exposure resulted in the lowest GSH-peroxidase activities in the blood and lung. High levels of vitamin E in the diet resulted in elevated GSH-peroxidase in the blood and lung. Liver GSH-peroxidase activity was unaffected by either dietary vitamin E or NO2 exposure. No inverse relationship was found between GSH-peroxidase levels and concentrations of organic solvent soluble lipofuscin pigments present in tissues.

Long-term NO2 exposure of mice in the presence and absence of vitamin E. I. Effect on body weights and lipofuscin pigments.

Mice on diets deficient in vitamin E, normal diets, diets with high supplements of vitamin E, and diets supplemented with N, N'-diphenyl-p-phenylenediamine (DPPD) were continuously exposed to 0.5 ppm or to 1.0 ppm nitrogen dioxide (NO2) or to filtered room air from weaning to 18 months of age. The effects of NO2 exposure on body weights, tissue weights, survival rates, and tissue organic solvent soluble lipofuscin (age) pigment concentrations were examined. Vitamin E deficiency resulted in lower body weights by 18 months of age; exposure to NO2 further increased this weight loss. With the exception of the kidney, tissue weights were not affected by NO2 exposure. Mice exposed to NO2 had lower survival rates than unexposed control animals. Tissue organic solvent soluble lipofuscin pigment (LFP) concentrations in the uterus, lung, spleen, kidney, liver, brain, and heart were not afffected by NO2 exposure. Only in the liver did vitamin E deficiency lead to an increase in LFP concentration; it did not occur in any of the other tissues examined.

Ascorbic acid and L-gulonolactone oxidase in lagomorphs.

1. The activity of L-gulonolactone oxidase (EC 1.1.3.8) in the liver of eastern cottontail rabbits (Sylvilagus floridanus) is about 10-fold greater in winter than in summer. 2. L-gulonolactone oxidase activity is low and tissue ascorbate high during all seasons in snowshoe hares (Lepus americanus). 3. Liver contents of ascorbate fall to low levels in L. americanus fed on rabbit chow in the laboratory. 4. The activity of L-gulonolactone oxidase in liver of Sylvilagus and Oryctolagus is depressed by feeding high levels of L-ascorbic acid. 5. The New Zealand White breed of domestic rabbit (Oryctolagus cuniculus) has considerably higher levels of L-gulonolactone oxidase and liver ascorbate than does the Dutch breed. 6. In a wild population of Oryctolagus sampled in Australia L-gulonolactone oxidase levels were intermediate between those of the two domestic breeds and more variable than either.

Effect of dietary vitamin E and aging on tissue lipofuscin pigment concentration in mice.

This study reports a re-investigation of the effect of dietary vitamin E upon tissue organic solvent soluble lipofuscin pigment concentrations. Female weanling mice were fed a vitamin E deficient, vitamin E or N,N'-diphenyl-phenylenediamine (DPPD) supplemented diet up to 18 months of age. Lipofuscin concentrations were measured by a quantitative method which is based on fluorescence spectroscopy. Of all tissues measured (uterus, lung, spleen, kidney, liver, heart and brain), only the liver responded and showed lower pigment concentrations due to vitamin E treatment. In addition, in the liver, up to 12 months of age, vitamin E supplementation resulted in gradually decreasing pigment concentrations, but by 18 months of age, pigment concentrations were increased by 5 to 10 times in all diet groups. The effect of DPPD was similar to vitamin E. Tissue lipofuscin pigment concentrations in 18-month-old mice were lowest in the uterus and highest in the heart. The data indicate the possibility of a turnover of the organic solvent soluble lipofuscin pigments in the liver.

Quantitative determination of organic solvent soluble lipofuscin pigments in tissues.

Lipofuscin pigment determination in tissue extracts was quantitated by the use of its property of fluorescence. Chloroform:methanol tissue extracts were purified on Sephadex LH-20 columns before quantitative fluorescence measurements of the lipofuscin pigments. Interfering compounds separated by chromatography were retinol and a lower mol wt fluorescent compound. Irradiation of tissue extracts with ultraviolet light was not sufficient to eliminate the interference caused by retional and the lower mol wt compound. Purified lipofuscin pigments from blood, lung, liver, spleen, brain, heart, and kidney tissues demonstrated distinct fluorescent emission maximum at 435 nm and excitation maxima between 345 and 350 nm.