We studied the influence of semiconductor laser irradiation on the cultured human epidermal keratinocytes and measured cell viability and the concentration of interleukin-1α (IL-1α) in the medium of irradiated cell cultures. We found that the number of viable cells in the cultures was significantly increased by giving semiconductor laser irradiation for 15s (115.0±0.5%), 20s (112.0±1.0%) compared with the number in the nonirradiated cultures (p<0.01). The production of IL-1α by cultured cells was increased by the laser irradiation for 20s (35.8±5.5pg/ml) compared with the control (27.0±5.6pg/ml) after a 12-h incubation period (p<0.01). These results imply that low-power laser irradiation has significant biological effects on human keratinocytes.
Dalton's lymphoma (DL), a spontaneous T cell lymphoma of mice, has been shown to inhibit macrophage activation in vitro. The present investigations were undertaken to study the mechanism of the DL-mediated macrophage inhibition. Reactive nitrogen intermediates (RNI) production of lipopolysaccharide (LPS)-treated macrophages could be reversed by the co-presence of a DL cell membrane preparation in the incubation mixture. One of the active macrophage inhibiting molecules of the DL cells was found to be the gangliosides. Incubation of macrophages with DL gangliosides (DLG) in vitro could inhibit the RNI production. DLG was found to act only at the initial stages of the LPS activation. Addition of DLG beyond 3h after the start of LPS treatment had no effect, showing that the DLG acted by altering some of the early events of the macrophage activation mechanism. In vivo administration of DLG also caused inhibition of RNI production of the macrophages. The DLG treatment was found to augment the proliferation of splenocytes by inhibiting the RNI production of the splenic macrophages. Indomethacin-treated DL cells were not significantly different from the untreated ones regarding their effect on the RNI production of macrophages, thus ruling out the involvement of metabolites of the arachidonate pathway in the modulation of macrophage activation by the DL cells.
The effect of copper overload on the red blood cell (RBC) membrane from experimentally copper-poisoned sheep was evaluated by studying the lipid peroxidation, composition of fatty acids, and protein organization of RBC membranes. Ten ewes were dosed orally with CuSO4 in order to induce copper toxicity. The level of lipid peroxidation products was examined in RBC ghosts by measuring their thiobarbituric acid reactivity. The measurement of fatty acids was accomplished by gas-liquid chromatography; and the study of membrane proteins, by SDS-PAGE. The results showed increased lipid peroxidation levels and reduced content of 18:1, 18:2, and 18:3 fatty acids in RBC from copper-poisoned sheep. Despite the RBC copper-overload, treated sheep showed a qualitatively normal protein pattern, but the amount of band 3 of membrane proteins increased. We established a relationship between copper overload and alterations in the RBC membrane structure.
We examined the protective effects of α-tocopherol against glucose intolerance and mitochondrial damage in rat liver after partial in vivo ischemia and reperfusion, while glucose was intravascularly supplemented. Rats were given α-tocopherol or vehicle for three consecutive days before the experiment. Left and median lobes of the liver received 90-min ischemia and 60-min reperfusion. Besides plasma levels of glucose, insulin, and lipid peroxide, we also measured oxidative phosphorylation, cytochrome c oxidase (CCO) activity, and lipid peroxide levels in mitochondria in both ischemic and non-ischemic lobes of the liver in control and α-tocopherol groups before and at the end of ischemia and after reperfusion. Both plasma glucose and insulin levels after reperfusion were lower in the α-tocopherol-treated group than in the control group. Ischemia markedly suppressed both mitochondrial respiration supported by succinate and CCO activity in the ischemic lobes in both groups. Reperfusion recovered mitochondrial function and CCO activity better in the α-tocopherol-treated group than in the control group, whereas the lipid peroxide levels in both plasma and mitochondria were significantly lower in the α-tocopherol-treated group. In non-ischemic lobes, ischemia-reperfusion slightly accelerated both the oxidative phosphorylation rate (OPR) and CCO activity, whereas lipid peroxide levels were unaffected. The results suggest that glucose intolerance during the early phase of reperfusion was not due to lowered plasma insulin level, but might be related to liver damage, as assessed in terms of mitochondrial functions, in the ischemic lobes. α-Tocopherol could protect against mitochondrial damage and glucose intolerance. Oxidative phosphorylation in non-ischemic lobes likely compensated for the decreased mitochondrial activity in the ischemic lobes during ischemia and reperfusion.
This paper describes the induction of DT-diaphorase by xenobiotic treatment of riboflavin-deficient rats. Upon injection of β-naphthoflavone once a day for 3 successive days into male Wistar rats fed a riboflavin-supplemented diet for 4 weeks, the activity of DT-diaphorase in the cytosolic, mitochondrial, and microsomal fractions of rat liver increased several fold compared with that of the vehicle control. In the case of rats fed a riboflavin-deficient diet for 4 weeks, DT-diaphorase activity in the cytosolic fraction was markedly decreased and that in microsomes was somewhat diminished, whereas the activity in mitochondrial fraction did not change, compared with that of the above control. However, when the deficient rats were injected with β-naphthoflavone intraperitoneally, DT-diaphorase activity in the cytosolic, mitochondrial, and microsomal fractions increased in spite of a significant decrease in flavin levels in the body. These results indicate that DT-diaphorase is actually induced even under conditions of riboflavin deficiency and that the apoprotein of the enzyme takes up FAD to become holoenzyme, suggesting a redistribution of FAD among various flavoproteins in the liver of riboflavin-deficient rats upon administration of a xenobiotic. Among the activities of other flavoenzymes examined, the occurrence of the apoenzyme of glutathione reductase, thioredoxin reductase or NADPH-cytochrome P450 reductase was found upon the injection of β-naphthoflavone in the riboflavin-deficient rats, which might be an indication of the above-mentioned redistribution.
To study the status of circulating lipid components in human uterine cervical carcinoma, we collected blood from patients with different stages of uterine cervical carcinoma before and after treatment and also from a control population. Serum lipid was isolated; and the total lipid and their components such as total cholesterol, high-density lipoprotein (HDL)2 cholesterol, HDL3 cholesterol, phospholipids, triglycerides, free fatty acids, and lipid-bound sialic acid were determined. Some of the lipid components like phospholipids, triglycerides, free fatty acids, and lipid-bound sialic acid were found to be increased in advanced stages (stages III and IV) of carcinoma, when compared with the values for control subjects. Some of the altered lipid parameters were adjusted to near normal levels after radiotherapy and radiotherapy combined with chemotherapy. The increase in some of the lipid components might have been due to the elevated activities of lipolytic enzymes.
The serum prolyl endopeptidase activities of patients with senile dementia of the Alzheimer type (SDAT) and of those with vascular dementia (VD) were measured by a sensitive fluorometric assay. As a result, the prolyl endopeptidase activity of both SDAT patients (p<0.025) and VD patients (p<0.001) was found to be significantly lower than that of normal subjects, and this activity of VD patients turned out to be significantly lower (p<0.001) than that of SDAT patients. The correlation between serum prolyl endopeptidase activity and that of other serum enzymes was examined, and a significant correlation was found with creatine kinase activity (r=0.560, p<0.001). Judging from these observations, it seems possible that the brain disorders of the dementia patients may have affected the metabolism of skeletal muscles, which possibly resulted in the lowering of their prolyl endopeptidase activity. At present, there are very few markers available for physiological diagnosis to distinguish between SDAT and VD patients, and therefore, the measurement of serum prolyl endopeptidase activities of dementia patients seems to be beneficial.