Influence of protein deficient diet, vitamin B[sub]2[/sub] supplementation and physical training on serum composition of polyunsaturated fatty acids (PUFAs) in rats.

[b]Introduction[/b]. Prolonged shortages of protein in the diet significantly alter the composition and content of polyunsaturated fatty acids (PUFA) in tissues and body fluids. One of nutritional factors which may reduce negative effects of protein malnutrition might be vitamin B[sub]2[/sub] due to its influence on lipids metabolism. [b]Objective. [/b]The aim of the study was to investigate the influence of low protein (LP) diet enriched with vitamin B[sub]2[/sub] on the content and composition of PUFA in the blood serum of rats treated with dosed physical exercise. [b]Materials and method. [/b]The experiment was carried out for 3 months on 72 growing male Wistar rats divided into 5 groups. Animals were fed ad libitum on a diet with an energy value of 350 kcal/100 g, in which 4.5% of the energy was provided by protein. In the control diet, 20% of the energy was provided by protein. Two groups were fed the diet enriched with vitamin B2. The two groups of tested animals were trained for 5 days a week. [b]Results.[/b] LP diet caused a decrease in α-linolenic acid (ALA) after 30 days, and a decrease in docosahexaenoic acid (DHA) after 60 days of experiment, compared with rats fed the control diet. After 60 and 90 days of the experiment, a significant decrease was noted in arachidonic acid (AA) in serum of trained rats, compared with sedentary rats fed the LP diet. Physical activity increased LA (mainly on day 30), EPA (on day 90) and reduced AA content (on day 90) in serum of rats fed the LP diet. B2 supplementation in the trained LP group did not change the EPA and AA dependence; however, there was a decrease in LA content in comparison to the non-supplemented trained group. [b]Conclusions. [/b] Results of this study suggest that all investigated factors (protein deficiency, physical exercise and supplementation of vitamin B2) have significant impact on PUFA composition of serum in rats.

The influence of vitamin B12 supplementation on the level of white blood cells and lymphocytes phenotype in rats fed a low-protein diet.

Protein malnutrition has a negative effect on body composition and some blood parameters, especially in the young growing organism. One of nutritional factors which could protect against negative consequences of protein deficiency may be B group vitamins. The aim of the study was to investigate the effect of vitamin B12 supplementation on the immune system in rats fed a standard and a low-protein diet. Rats were fed a control (20% of energy from protein) or a protein-deficient diet (4.5% of energy from protein). Half of animals in each group were additionally supplemented with vitamin B12 (300% of the daily intake). The white blood cells analysis and lymphocytes immunophenotyping (number and percentage) were performed. Low-protein diets caused disturbances in WBC and lymphocyte subpopulations in both short- (30-day) as well as long-term periods (90-day). Vitamin B12 supplementation significantly reduced the negative impact of protein malnutrition after 30 days, however had no effect on long-term malnutrition. Furthermore, vitamin B12 addition in rats fed a control diet did not affect the studied parameters. This observation opens the promise of use of vitamin B12 supplementation to improve immune system parameters in protein malnourished organisms.

Polyunsaturated fatty acid (PUFA) changes in serum and liver of undernourished rats given dietary vitamin B6 supplementation.

The influence of vitamin B6 on linoleic (LA), alpha-linolenic (ALA), arachidonic (AA), eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid content in serum and liver of rats fed with protein-energy deficient diets for 90 d, was studied. To estimate the effect of dietary supplementation with vitamin B6 on the composition and level of fatty acids in the serum and liver of rats, two experiments were performed. In these experiments control rats were fed ad libitum semisynthetic isocaloric diets of 1,466.5 kJ/100 g (350 kcal/100 g) throughout 90 d while the examined rats were offered 50% and 30% of the previously determined daily intake of the diet consumed in the control group. The experimental diet was supplemented with vitamin B6 to the level 4-times higher than in the control diet. A reduction to the half consumption of a standard diet supplemented with vitamin B6 caused a significant decrease of LA and ALA in blood serum at 30 and 60 d. At 90 d of the experiment the value of LA was lower and the content of AA was higher in comparison to the control group. After 30 d of consumption of vitamin B6 enriched diet in rats subjected to feed restriction to only 30% of the control intake, an increase of ALA and a decrease of AA, EPA and DHA were noticed in serum. At 60 d an increase of DHA was observed. Ninety days of feeding this diet caused a significant increase of AA level. Feeding animals for 90 d with a vitamin B6 enriched diet, with limited consumption to 50%, caused a significant increase of ALA content in liver. Further limitation of this diet consumption to 30%, caused a significant decrease of LA and ALA and an increase of EPA content.

Influence of vitamin B6 supplementation on polyunsaturated fatty acids concentration in serum and liver of rats fed a diet restricted in protein.

The influence of vitamin B6 on fatty acids content in serum and liver of rats receiving low protein diets was studied. Addition of B6 decreased linoleic acid (LA) and increased alpha-linolenic acid (ALA) and docosahexaenoic acid (DHA) in serum of rats fed a protein-deficient diet (9% energy from proteins) for 3 months. Further restriction of dietary protein (4.5% of energy from protein) caused an increase of the DHA concentration and sum of polyunsaturated fatty acids (PUFAs). In the liver of undernourished rats significant changes of PUFA composition were noticed, although without any significant influence of vitamin B6.

Effect of restricted feed intake and addition of vitamins B2 and B6 and folic Acid on the liver concentration of zinc and copper in rats.

The aim of the present study was to investigate the influence of nutritional deficiency and dietary addition of vitamins (B2, B6, and folate) on hepatic concentration of zinc and copper in rats. The experiment was performed on 260 growing male Wistar rats divided into 13 groups. Animals of 11 groups were fed isocaloric diets (14.7 MJ/kg) in which the 20% of energy was derived from protein. Another two groups of rats were offered diets with 9% or 4.5% of energy originating from protein. Animals of both mentioned groups and of the control group (20% of energy from protein) were offered diets ad libitum. The other 10 groups were offered 50% and 30% of the amount consumed in the control group. Eight groups, from those 10 restricted ones, were differentiated by dietary addition of vitamins B2 and B6 and folate (300% addition). Restricted feed intake did not affect the liver zinc concentration but significantly increased the copper concentration. The addition of vitamin B6 decreased the liver Zn concentration. The highest liver Cu concentration was noted in rats offered restricted diets to only 30% of intake in the control group and high in vitamin B2 and in rats supplemented with all of studied vitamins together. It suggests that vitamin B2 had the strongest impact on liver Cu concentration in rats fed restricted diets.

Content of polyunsaturated fatty acids (PUFAs) in serum and liver of rats fed restricted diets supplemented with vitamins B2, B6 and folic acid.

The aim of study was to investigate an influence of nutritional deficiency and dietary addition of vit. B(2), B(6) and folic acid on PUFAs content in rats' serum and liver. Limitation of consumption full value diet to 50% of its previously determined daily consumption, enriched with m/a vitamins, significant decreased of linoleic (LA) and alpha-linolenic (ALA) acids as well as distinctly increased arachidonic (AA) and docosahexaenoic (DHA) acids content in serum in 30th day. In 60th day lower content of AA and DHA fatty acids was found. Nutrition with such diet, lasting 90 days caused decrease of LA content and increase of AA. Diet limitation to its 30% of daily consumption decreased of eicosapentaenoic acid (EPA) and DHA in the 30th day, while AA and DHA content was increased in the 60th day. Distinct decrease of AA content and increase of EPA content were found in the 90th day of experiment. Use of diets, with limited consumption to 50% caused increase of LA and ALA acids content while AA and DHA acids content were significantly decreased in the liver, in 90th day. Limited consumption supplemented diet to 30% caused in liver significant decrease of LA and increase of EPA acids content.