This study aims to compare the electron spin resonance (ESR) spectra emitted by human blood loaded with either ascorbyl-6-palmitate (AP), a lipid-soluble derivative of ascorbic acid (AA), or with AA. ...Whole blood of a healthy male individual was equilibrated with equimolar concentrations of AP and AA of 200, 400, and 800 micromol/l. The intensity of the ESR signal, expressed as the peak-to-peak amplitude, reflects the amount of unpaired spins that are created due to the reducing action of AA and is proportional, in relative terms, to the amount of the ascorbyl radical formed. We found that the blood with AP emitted an ESR signal whose singlet shape, width, and location precisely correlate with the known characteristics of the ascorbyl radical in vitro. The signal magnitude increased linearly with increasing concentrations of AP and was similar to that of AA. We conclude that AP is biologically active, as it generates the ascorbyl radical, an action that also underlies the scavenging process by ascorbic acid. To this end, ascorbyl-6-palmitate might have potential advantages, due to its ability to penetrate biomembranes and to act at the lipid-related molecular target sites.
Fluorine 19F is one of few 'lucky' elements found in living organisms, whose nucleus is characterised by non-zero spin, which makes it possible to detect fluorine and to analyse (and image) its ...chemical compounds with the help of Nuclear Magnetic Resonance (NMR). Fluorine 19F spectroscopy is not as popular as that of hydrogen 1H or phosphorus 31P, however, this method has recently been developed and applied (in medicine, too) more and more frequently, despite technical problems. This paper is a brief introduction to the techniques of investigating fluorine 19F with NMR spectroscopy, providing insight into the peculiarities and the difficulties associated with this method. It is also a short review of the achievements in NMR fluorine investigations in the fields of biology and medicine.
The effect exerted on the ascorbate system due to the exposure of mice to the constant magnetic field associated with MRI methods has been examined. The mice were exposed to magnetic field 1.00 T ...strength for 0.2 h, 3 h, or 24 h. The ascorbyl free radical in tissues was measured in vitro, which in vivo corresponds to the level of ascorbic acid. Only in a group of mice where the ascorbyl free radical was measured 24 h following their exposure to magnetic field 1.00 T strength for 24 hours, was the level of free radical in tissues significantly decreased.
Eighteen children with steroid-sensitive nephrotic syndrome (SSNS) were studied. The control group comprised 20 healthy children. The following indirect parameters of reactive oxygen species activity ...were determined in nephrotic patients during four stages of the disease (full relapse before prednisone administration, disappearance of proteinuria, prednisone cessation, unmaintained remission): plasma malondialdehyde (MDA) levels, copper/zinc superoxide dismutase (CuZn SOD) activity and glutathione peroxidase (GPX) activity in erythrocytes, reduced glutathione (GSH) and vitamin C levels in whole blood, and vitamin E level in serum. Increased MDA levels, reduced vitamin C levels, and enhanced CuZn SOD activity were found in relapse. GSH concentration was high during all four stages. Vitamin E level was also increased, parallel to the pattern of serum lipids. GPX activity remained low during the proteinuria stage and in remission. We conclude that the majority of abnormal findings can be attributed to the hyperlipidemia of NS. Low GPX activity may be a factor limiting the antioxidant capacity in NS. The present study is inconclusive regarding the role of free radicals in the proteinuria of NS.
Atherosclerosis was induced in male mongrel rabbits with a high-fat diet and the influence of essential phospholipids (EPL) on plaque formation, parameters of lipid metabolism and immunological ...functions was studied. When EPL were added to the high-fat diet there was a significant reduction in the area of atherosclerotic involvement of the aorta. The serum concentration of lipids decreased, often to normal values, and cholesterol esterified with polyunsaturated fatty acids appeared. Normalization of the malonyldialdehyde level in plasma was accompanied by a decrease in the concentration of ascorbate free radicals in blood and liver. The high-fat diet caused a depression of both non-specific and specific immune functions studied. With EPL in the diet the tests showed near normal or normal values. It is inferred from these results that a normal state of the immune system is important for preventing the progress of atherosclerotic changes. This is discussed with reference to the role of some immune cells in the metabolism of lipids and to participation of essential phospholipids in plasma membrane functions.
Fertilised Ascaris suum eggs were subjected to an alternating electromagnetic field of frequency 50 Hz and density 2 mT for 60 days. The developing embryos in both control and experimental cultures ...were examined daily under a microscope. The experiment resulted in an accelerated rate of embryogenesis in the eggs incubated in the electromagnetic field, higher rates of malformed embryos as well as much higher mortality rate of L2 larvae.
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