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Vitamins are essential for the health of all living organisms. Vitamins E, A, D and K are known as fatsoluble vitamins, and deprivation of vitamin E causes various disorders, especially in the reproduction and cardiovascular systems and in muscle functions. Vitamin A, on the other hand, has roles in various biological functions – like eyesight – and the growth, reproduction and differentiation of epithelial cells. Vitamin A deficiency leads to the keratinization of the epithelium, and disorders related to the metaplasies of the genital and genitourinary systems. Conversely, vitamin D is defined as a pro-hormone and is responsible for Cahomeostasis, and thus indirectly affects the bone metabolism, bone structure, and cellular and neural functions of Ca. White Muscle Disease (WMD) can occur in newborn lambs, but is more commonly seen in lambs of up to 3 months of age. In this study, 30 lambs of 3 to 50-days-old from different flocks diagnosed with White Muscle Disease (WMD) were selected as research material, while the control group consisted of 8 healthy lambs. With the aim of clarifying the cause of WMD, serum fat-soluble vitamins, retinol, α-tocopherol and vitamin D3 levels were determined in 16 lambs. Gluteal and heart musclet issue samples also were taken from 30 lambs with WMD. The vitamin levels of the samples were analysed by HPLC. The levels of serum α-tocopherol, retinols, and vitamin D3 were foundto be low in the diseased animals, but only retinol (p < 0.001) and α-tocopherol (p < 0.001) level differences were statistically relevant. Macroscopically, Zenker’s necrosis was determined in the heart muscles of 17 lambs, and in the gluteal and chest muscles of 6 lambs. 7 lambs displayed necrosis in both their heart and in gluteal muscles. The samples were analyzed microscopically to reach similar findings: swollen homogeneous pink muscles, pycnotic nuclei, and hyperaemic and haemorrhagic blood vessels in gluteal, chest and heart muscles. Hyaline degeneration and Zenker’s necrosis, dystrophic regions in necrotic areas, cc was detected as a severe disease in lambs at an early stage of life with advanced degeneration in different muscle tissues. Deficiency of fat-soluble vitamins was also detected in the sick animals. Control group lambs had higher levels of α-tocopherol and retinol (p < 0.001) compared to the sick lambs.
An tioxidantvita mins, being effective free radical scavengers, can protect cellular DNA from ox i da tive dam age. Therefore, in the pres ent study we re port on the re la- tion ship be tween basal level of 8-oxo-2 -deoxyguanosine in hu man lym pho cyte DNA and the concentration of antioxidant vitamins (A, C and E). The average level of 8-oxo-2 -deoxyguanosine in lymphocytes of the studied group (15 males and 20 fe­males) was 9.57 per 106 dG mol e cules. The en dog e nous level of ascor bic acid (vi ta min C) in the plasma was, on av er age, 56.78 uM, while the mean con cen tra tions of retinol (vi ta min A) and α-tocopherol (vi ta min E) were 1.24 uM and 25.74 uM, re spec tively. No correlations were found between individual 8-oxo-2 -deoxyguanosine levels in lymphocyte DNA and en dog e nous con cen tra tion of the vi ta mins.
Concentrations of serum sialic acid, malondialdehyde (MDA), retinol, zinc, and copper were measured in 52 lactating Holstein cows. Out of them, 15 were controls, 21 mildly lame, 7 moderate lame, and 9 severely lame. The animals were housed in free-stall barns with a slurry surface and were not released for pasture feeding. Compared to control animals, the mean serum total sialic acid concentrations in animals with severe lameness, but not in those with mild and moderate lameness, were increased significantly (P<0.01). The levels of MDA were higher in severely lame animals than in controls as well as in mildly and moderately lame animals and the differences were statistically significant (P<0.001). Contrary to the elevated serum concentrations of sialic acid and MDA in severely lame cows, the mean serum retinol value of these animals showed a remarkable decline (P<0.05). As for serum zinc and copper concentrations, there were statistically no significant alterations between the groups. In conclusion, results of the present study indicate that the concentrations of serum total sialic acid, MDA and retinol are associated with a degree of the lameness.
Human papillomavirus (HPV) infection is a major risk factor for the development of cervical cancer. The HPV-induced immortalization of epithelial cell usually requires integration of the viral DNA into the host cell genome. The integration event causes disruption of the E2 gene and this is followed by overexpression of the E6 and E7 oncoproteins. The E2 protein is a transcription factor that regulates expression of the E6 and E7 oncoproteins by binding to four sites within the viral long control region. We used an in vitro cell culture model to explore the role of the E2 protein in the transcriptional control of the HPV16 long control region. Employing transient and stable transfection experiments we simulated the episomal and integrated states of the viral genome, respectively. We show that the E2 protein up-regulates E6/E7 transcription from episomal DNA but represses it in the case of integrated DNA. The activator function of the E2 protein seems to counteract the repressive chromatin structure formed over episomal DNA. Steroid hormones and retinol also modulate oncogene transcription differently depending on the physical structure of the viral DNA. Our data suggest regulatory mechanisms involving interactions between the E2 protein and nuclear hormone receptors.
Objectives: Obesity, insulin resistance and dyslipidemia are the most significant risk factors of non-alcoholic fatty liver disease (NAFLD) but the role of adipokines in the pathogenesis of this disease is not clear. Assessment of retinol binding protein (RBP-4) seems to be promising because data from animal and human studies suggest its role in the patomechanism of insulin resistance. Therefore, the aim of the study was to evaluate the serum levels of RBP-4 in children with NAFLD. Methods: Fasting serum level of RBP-4 was determined in 42 obese children with suspected liver disease and 20 lean controls. The degree of liver steatosis was graded in ultrasound according to Saverymuttu. The intrahepatic lipid content was assessed noninvasively in a semiquantitative fashion using 1HMR spectroscopy (1.5-T scanner with PRESS sequence). Results: Fatty liver was confirmed in 30 children by ultrasonography (16 of them had also increased alanine transaminase (ALT) activity). Serum concentrations of RBP-4 were significantly higher in obese children with NAFLD compared to controls. Significant correlations were found between RBP-4 level and ultrasonographic grade of liver steatosis, intrahepatic lipid content (1HMRS) and triglycerides level, while the serum level of RBP-4 was not significantly higher in children with advanced liver steatosis (grade 2-3, n = 11) compared to patients with mild steatosis (grade 1, n = 19). The ability of RBP-4 to differentiate children with advanced liver steatosis from those with mild steatosis was not significant. Conclusion: RBP-4 can be considered as a convenient serum marker of intrahepatic lipid content in obese children.
Male rats of Wistar strain (n = 48) were fed a vitamin A deficient diet for 3 days of adaptation period and then a 10 day experimental period to reduce slightly the body stores of this vitamin. Half of the animals were subjected to physical training and/or oral vitamin A supplementation. Four different doses of supplementation were used – 0, 7.5, 15 and 60 μg/d/rat, which is equivalent to 0, 25, 50 and 200 IU of vitamin A, respectively. Animals from the defined groups ran on a treadmill with a rate of 2.0 m/s for 15 minutes per day for 10 days. After overnight fasting, the rats were sacrificed, and insulin in blood serum and hepatic retinol concentrations were estimated. Daily feed intake and daily body gains were similar in groups of sedentary and physically trained rats. A moderate level of oral vitamin A supplementation (the highest supplemented dose was about 6 x the above recommended NRC level) did not cause any changes in these zootechnical parameters. Oral Vitamin A supplementation resulted in an increase in retinol concentration in the liver (F = 15.2, p < 0.001), but without significant difference between trained and untrained animals. Physical training of rats caused a statistically significant decrease of insulin concentration in blood serum (1.53 ± 0.18 vs. 1.73 ± 0.20). This difference was highly significant (F = 11.1, p < 0.001). Vitamin A supplementation was found not to influence the concentration of this hormone, which is responsible for energy metabolism regulation in the body. Based on estimated parameters, the necessity of vitamin A excessive use in physically trained subjects was not proven.
The effects of lead, copper, cadmium and mercury on the content of chlorophyll, proline, retinol, α-tocopherol and ascorbic acid were investigated in 17-day-old bean seedlings (Phaseolus vulgaris L.) grown in Hoagland solution spiked with various concentrations of Pb, Cu, Cd and Hg. Control and heavy metal-treated plants were grown for 10 days in Hoagland solution. Content of total chlorophyll (a and b), proline, retinol, α-tocopherol and ascorbic acid was measured in ten-day-old primary leaves by High Performance Liquid Chromatography (HPLC). Total chlorophyll content declined progressively with increasing concentrations of heavy metals. A significant increase of proline, retinol, α-tocopherol and ascorbic acid content was detected in primary leaves after ten-day exposure to heavy metals. The strongest effect on total chlorophyll, proline, retinol, α-tocopherol and ascorbic acid content was found in plants exposed to mercury, followed by the sequence Cd++ > Cu++ > Pb++.
Cell metabolism in organisms which use oxygen as a source of energy is closely associated with the generation and action of free oxygen radicals and their derivatives. Extra- and intracellular substances that are antioxidative in nature prevent overproduction of radicals and protect against propagation of peroxidative reactions. The list of compounds which can be treated as antioxidants becomes elongated. Many classifications of these compounds are used, of which the most common is the division according to their nature into enzymatic and non-enzymatic, according to their environment or the way they react with FOR. Enzymatic antioxidants include: superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase. Non-enzymatic antioxidants are: vitamin E, vitamin C, glutathione, carotenes and retinols, and some transition metals (Zn, Cu and Se). The balance between the actions of these two groups of compounds determines normal functioning of the organism. Impairment of the balance between pro- and antioxidative processes in the organism is called anitoxidative stress and may be induced by intensified reactions involving FOR and by depressed activity/concentration of antioxidants. It seems, however, that irrespective of the cause, oxidative stress is likely to result in many diseases.
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