Corriedale ewes were exposed to ration and a pasture containing a high level of copper to study the relationship between peroxidation of lipid membrane and copper-induced hemolysis. We measured phospholipids, cholesterol, and protein from red blood cell (RBC) ghosts, and lipid peroxidation. A decrease in total phospholipids in the erythrocyte membranes and an increase in lipid peroxide levels of erythrocytes was observed in blood samples from animals that ingested large amount of copper. The cholesterol concentration was not altered in RBC. Additionally, depressed phospholipid/protein and phospholipid/cholesterol ratios were found. These data suggest that elevated copper levels have a deleterious effect on membrane integrity through the peroxidation of lipids. It is reasonable to postulate that these alterations were a possible cause of hemolysis.
Tumor-reducing effect in vivo and antioxidant effect in vitro of 12 sydnone-substituted chalcones having various groups on the benzene ring were studied. All of them were found to be cytotoxic to tumor cells in vitro, while only methyl substitution increased the in vivo tumor-reducing activity. Some of the substituted chalcones were found to inhibit lipid peroxidation and scavenge superoxides and hydroxyl radicals in vitro. The biological activities of the chalcones were compared with those of curcumin I, an analog of chalcone with known antioxidant activity; and although the sydnone-substituted chalcones had higher cytotoxicity than curcumin I, their tumor-reducing and antioxidant activity were lower. Tumor-reducing activity was found to be independent of their antioxidant activity.
The effect of L-carnitine on serum lipids was studied in rats with experimentally-induced atherosclerosis. L-Carnitine at a dose of 300mg/kg body weight was given intraperitoneally for 7 days after the induction of atherosclerosis. Carnitine caused a significant reduction in the levels of serum cholesterol, triglycerides, phospholipids, and free fatty acids and elicited a significant increase in HDL cholesterol. The significant reduction observed in the LDL/HDL ratio is prominent from the therapeutic point of view in the treatment against hypercholesterolemia in experimental atherosclerosis.
After 2-4 months of age, accelerated senescence-prone mice showed a higher level of serum triglycerides and lower levels of total cholesterol and phospholipids than accelerated senescence-resistant mice. At 2-4 months of age, the former strain showed higher levels of very low density lipoprotein and low density lipoprotein and a lower level of high density lipoprotein-cholesterol than the latter strain. The serum lipid peroxide level per mg of serum lipids was higher in the former than in the latter. These results indicate that a disorder in the metabolism of lipids and lipoproteins occurs concomitantly with the increase in serum lipid peroxide level in this animal model of accelerated aging.
The levels of β-carotene, retinol, vitamins E and C, lipid peroxides, ceruloplasmin, and selenium were investigated in 238 patients with different stages of cervical cancer and in 125 controls individually matched for age. Vitamin and selenium levels were found to be decreased in the stages III and IV patients, whereas lipid peroxides and cerulopla min were increased from stage III onwards. The altered levels were normalized after the end of the radiotherapy in the stage III patients. These observations suggest that the decreased levels of vitamins and increased lipid peroxides in cervical cancer patients in advanced stages (stages III and IV) may be the consequence of the neoplastic process. Furthermore, this study suggests that the normalization of these constituents in stage III patients might be an indicator of the prognostic effect of radiotherapy in carcinoma of the uterine cervix.
To investigate the influence of intestinal flora upon the effects of biotin deficiency, we provided germ-free and conventional mice with a purified biotin-deficient diet without egg white for 20 days. Some of the biotin-deficient germ-free mice exhibited alopecia, while conventional mice on the same diet did not. Biotin levels decreased significantly in tissues of conventional and germ-free mice fed a biotin-deficient diet except in the heart of the conventional mice. Pyruvate carboxylase activity in the liver and kidney of germ-free mice fed the deficient diet also decreased significantly, while the activity in the liver of conventional mice on the same diet showed only a slight decrease. However, no significant differences in body or tissue weights were observed between germ-free and conventional mice during the short experimental period. Thus, conventional mice fed a biotin-deficient diet showed latent biotin deficiency, while germ-free animals fed the same diet exhibited severe biotin deficiency. Enteral microbial synthesis of biotin may have made some contribution to the observed amelioration of the effects of dietary biotin deficiency.
The chemiluminescence (CL) emitted from polyaromatic hydrocarbons (PAH) and aflatoxins (AF) in an S9 mix system can be detected by use of a chemiluminescence analyzer. These CL intensities were significantly correlated with the degree of mutagenicity as measured by the Ames test (using S. typhimurium TA 100), and of clastogenicity measured by the micronucleus test using ICR mice. The emission spectra of the CL detected from aflatoxin B1 (AFB1) indicated a distinctive blue light around 440nm. In the case of AFs, there was a strong correlation between CL intensity and genotoxicity. CL intensity detected from nonsubstitutional polyaromatic hydrocarbons was significantly correlated with the degree of superdelocalizability. These CL emissions observed from PAHs and AFs not only correspond to the genotoxicity of these compounds but also reflect the electronic configuration of them.