Influence of vitamin E on the levels of fatty acids and MDA in some tissues of diabetic rats

This study was performed to determine whether vitamin E supplementation in streptozotocin-induced diabetic rats treated with insulin could affect the levels of fatty acid composition and malondialdehyde (MDA) of brain, liver and muscle tissues. Thirty Wistar albino rats were used during the experiments. They were randomly divided into three groups, each consisting of six individuals. The first group was diabetic, the second was control, and the third was diabetic but fed vitamin E. The level of stearic acid in brain tissues decreased (p<0.05) in the second and the third groups as compared to the first group. The percentage of arachidonic and polyunsaturated fatty acids slightly decreased (p<0.05) in the diabetic group in comparison to the second and third groups. The proportion of docosahexaenoic acid significantly increased (p<0.01) in the second and third groups in contrast to the first group. The level of docosatrienoic was slightly higher (p<0.05) in the third group than in other groups. In the liver tissues, the proportion of stearic, oleic and total monounsaturated fatty acids was slightly higher (p<0.05) in the first group than in the other groups. The level of arachidonic, docosahexaenoic, unsaturated and total polyunsaturated fatty acid slightly increased (p<0.05) in the second and third groups as compared to the first group. The level of myristic and stearic acids in muscle tissue slightly increased (p<0.05) in the first group as compared to the second and third groups. The proportion of arachidonic, docosahexaenoic and unsaturated fatty acids slightly increased (p<0.05) in the second and third groups relative to the first group. The amount of MDA was slightly higher in the diabetic group than in the other groups in all tissues. The results indicate that vitamin E supplementation, in experimental diabetes could play a role in controlling the oxidative status and altered fatty acid metabolism in tissues, thereby maintaining favourable fatty acid distribution in the tissues affected by diabetic complications.     

In vivo and in vitro effects of some plant hormones on rat erythrocyte carbonic anhydrase and glucose-6-phosphate dehydrogenase activities

The present study was undertaken to determine in vivo and in vitro effects of some plant growth regulators on rat erythrocyte carbonic anhydrase (CA) and glucose-6-phosphate dehydrogenase (G6PD) activities. Both in vivo and in vitro, spermidine and kinetin did not affect enzymatic activities of CA and G6PD, whereas putrescine decreased these activities, and abscisic acid increased them. Since plants use such growth regulators, their effects should be considered on mammals consuming them since they may possess important biological effects.     

Effects of triple antioxidant combination (vitamin E, vitamin C and alpha-lipoic acid) with insulin on lipid and cholesterol levels and fatty acid composition of brain tissue in experimental diabetic and non-diabetic rats

The aim of this research was to examine the effects of a triple antioxidant combination (vitamins E (VE) and C (VC) plus alpha-lipoic acid (LA)) on the total lipid and cholesterol levels and the fatty acid composition of brain tissues in experimental diabetic and non-diabetic rats. VE and LA were injected intraperitoneally (50 mg/kg) four times per week and VC was provided as a supplement dissolved in the drinking water (50 mg/kg). In addition, rats in the diabetes 1 and D+VELAVC groups were given daily by subcutaneous insulin injections (8 IU/kg), but no insulin was given to rats in the diabetes 2 group. The results indicate that the brain lipid levels in the D+VELAVC, diabetes 1 and diabetes 2 groups were higher than in the control group (P<0.01). Total lipid was also higher in the non-diabetic rats treated with LA and VC. Total cholesterol was higher in the diabetes 1 and diabetes 2 groups (P<0.05) than in controls. Cholesterol levels were similar in the D+VELAVC and LA groups but lower in the VC, VE and VELAVC groups of non-diabetic rats (P<0.05 and P<0.01). In respect of fatty acid composition, palmitic acid levels were lower in the diabetes 2 and non-diabetic VE groups than the control group (P<0.05), but higher in the non-diabetic LA group (P<0.05). Oleic acid (18:1 n-9) levels were lower in the diabetic and non-diabetic groups than the control group (P<0.01), but higher in the non-diabetic LA group. Arachidonic acid (20:4 n-6) levels were similar in the diabetes 1, D+VELAVC and control groups (P>0.05) but higher in the non-diabetic VE, VC, LA and VEVCLA groups (P<0.05) and lower in the diabetes 2 group (P<0.05). Docosahexaenoic acid (22:6 n-3) was elevated in the diabetes 2 and VEVCLA groups (P<0.01, P<0.05). In conclusion, the current study confirmed that treatment with a triple combination of VE, VC and LA protects the arachidonic acid level in the brains of diabetic and non-diabetic rats.     

Wetlands in flux: looking for the drivers in a central European case

Planet Earth is undergoing significant changes which are driven by natural and anthropogenic factors. However, it is difficult to identify the drivers and their effect on the environment and ecosystems because there are many interdependencies. In this study we present a multi-parameter approach to assess the effect of changes in human-induced and natural drivers on a wetland ecosystem. The study area is one of the most prominent European wetlands: the Biebrza Basin, located in north-eastern Poland. We analysed long-term (ca. 1960–2000) changes in meteorology, hydrology, soil and vegetation, and also conservation history. This approach enabled us to identify interactions between environmental change and management. We found significant trends (1960–2012) indicating climate change: increases in temperature, evapotranspiration and earlier start of spring floods. We identified (1970–2000) a shift towards drier vegetation types after drainage. However, we also found that restoration measures that were implemented have mitigated climate change effects and have led to increases in soil moisture and wetter vegetation types. We conclude that, if carried out sufficiently frequently, the management measures implemented in the Biebrza Basin, which are a combination of different restoration measures (blocking drainage, not clearing aquatic vegetation, bush removal, mowing), can to some extent mitigate the effects of climate change.     

Sustainable intensive livestock production demands manure and exhaust air treatment technologies

Intensive livestock production is connected with a number of environmental effects, including discharges to soils and surface waters and emissions to the atmosphere. In areas with a high livestock density the low availability of nearby arable land, together with the preferred use of chemical fertilizer by arable farmers, results in high off-farm disposal costs for manure. Furthermore, ammonia abatement technologies, such as treatment of exhaust air, are important as ammonia emissions may account up to a quarter of the total nitrogen flux.     

Antimicrobial and biological effects of N-diphenylphosphoryl-P-triphenylmonophosphazene-II and di(o-tolyl) phosphoryl-P-tri(o-tolyl)monophosphazene-III on bacterial and yeast cells

The purpose of the study was to synthesize and evaluate the antimicrobial effects of two monophosphazenes, N-diphenylphosphoryl-P-triphenylmonophosphazene-II and N-di(o-tolyl)phosphoryl-P-tri(o-tolyl)monophosphazene-III on bacterial and yeast strains. The biological effects of these molecules were compared with a potential antioxidant vitamin E. According to results, the triphenyl monophosphazene-II has antimicrobial effect on all the bacterial and yeast cells, but tri(o-tolyl)monophosphazene-III has only antimicrobial effect on some bacterial cells. When the concentration of triphenyl monophosphazene-II was raised, it was observed that inhibition zone increased on the bacterial growth media. The biological effects of these molecules were compared to vitamin E in the Saccharomyces cerevisiae culture media. In 200 microg administered culture media, the cell density decreased in vitamin E, triphenyl monophosphazene-II and tri(o-tolyl)monophosphazene-III groups at the end of 24 and 48 h incubation times (p<0.001,p<0.05). While the cell densities in vitamin E and tri(o-tolyl)monophosphazene-II groups decreased partly at the end of 72 h incubation time (p<0.05), its level in triphenyl monophosphazene-II group increased (p<0.01) at the same incubation time. In 1,000 microg administered culture media, cell density was not found to differ between vitamin E and control groups at the end of 24h incubation time, but it was found that the cell densities in triphenyl monophosphazene and tri(o-tolyl)monophosphazene-III groups decreased at the same incubation time (p<0.001). The cell densities in tri(o-tolyl)monophosphazene-III group and triphenyl monophosphazene-II decreased at the end of 48 h incubation time (respectively, p<0.05,p<0.001). In 200 microg administered cell pellets, while the lipid level was not found to differ between control and vitamin E, the lipid level decreased in triphenyl monophosphazene-II and tri(o-tolyl)monophospazene-III groups (respectively, p<0.001,p<0.01). In 1,000 microg administered cell pellets, it was found that the lipid level decreased in vitamin E, triphenyl monophosphazene-II and tri(o-tolyl)monophosphazene-III groups (p<0.001,p<0.01).     

Effects of salicylic acid and cold treatments on protein levels and on the activities of antioxidant enzymes in the apoplast of winter wheat leaves

The effects of salicylic acid (SA) and cold on apoplastic protein levels and activities of apoplastic catalase (CAT), peroxidase (POX) and polyphenol oxidase (PPO) were investigated in winter wheat (Triticum aestivum cv. Dogu-88) leaves. The plants were grown with and without 10 microM SA treatment at both control (20/18 degrees C for 30 and 45-day) and cold (10/5 degrees C for 30-day and 5/3 degrees C for 45-day) acclimatisations. Molecular masses of the apoplastic polypeptides were shown ranging in size from 20 to 66 kDa on SDS-PAGE. Accumulation and pattern of the polypeptides were changed by both SA and cold. It is observed that CAT, POX and PPO activities at 45-day control leaves were higher than at 30-day. When the activities with SA and cold treatments are compared to their controls, CAT activities were decreased while POX and PPO activities were increased by both the treatments. When the activities with cold+SA treatment are compared to their cold treatments, CAT and POX activities were decreased while PPO activity was increased by SA. It is concluded that exogenous SA can be involved in cold tolerance by regulating apoplastic proteins and antioxidant enzyme activities.     

Effects of intraperitoneally administered ubiquinone on the level of total lipid and fatty acids in rat liver

The purpose of the present study was to evaluate the effect of ubiquinone (coenzyme Q-10) on total lipid and fatty acid composition of liver tissues in rats. Twenty male wistar rats were randomly divided into two groups. The first group was used as a control. The second group received ubiquinone (8 mg/every other day) intraperitoneally. This administration was done for a period of 38 days. Body weight increases in animals fed diets for 38 days were on average 35 g in control group (C), and only 11 g in the ubiquinone group. Total lipid content of liver tissues in the ubiquinone group (UB) decreased significantly (p < 0.0001) compared to the control group (C). The ratio of 22:6 and total omega3 fatty acid in the UB increased (p < 0.01) compared to C. While the level of oleic acid (18:1), palmitoleic acid (16:1) and total monounsaturated fatty acid (MUFA) in UB significantly decreased (p < 0.01, p < 0.001, p < 0.001, respectively), the level of stearic acid (18:0) in liver tissue increased (p < 0.05) in the same group when compared to C. Stearoyl-CoA desaturase (SCD) is the rate-limiting enzyme catalyzing the synthesis of monounsaturated fatty acid mainly oleate (18:1). We speculate that ubiquinone inhibits SCD activity. SCD is an important metabolic control point in body weight regulation. Our results indicate that ubiquinone supplementation may have an inhibitory effect on obesity and it seems that the level of 22:6 in liver increased due to ubiquinone.     

Antifreeze proteins in higher plants

Overwintering plants produce antifreeze proteins (AFPs) having the ability to adsorb onto the surface of ice crystals and modify their growth. Recently, several AFPs have been isolated and characterized and five full-length AFP cDNAs have been cloned and characterized in higher plants. The derived amino acid sequences have shown low homology for identical residues. Theoretical and experimental models for structure of Lolium perenne AFP have been proposed. In addition, it was found that the hormone ethylene is involved in regulating antifreeze activity in response to cold. In this review, it is seen that the physiological and biochemical roles of AFPs may be important to protect the plant tissues from mechanical stress caused by ice formation.     

DynaBiS: A hierarchical sampling algorithm to identify flexible binding sites for large ligands and peptides

Knowing the ligand or peptide binding site in proteins is highly important to guide drug discovery, but experimental elucidation of the binding site is difficult. Therefore, various computational approaches have been developed to identify potential binding sites in protein structures. However, protein and ligand flexibility are often neglected in these methods due to efficiency considerations despite the recognition that protein–ligand interactions can be strongly affected by mutual structural adaptations. This is particularly true if the binding site is unknown, as the screening will typically be performed based on an unbound protein structure. Herein we present DynaBiS, a hierarchical sampling algorithm to identify flexible binding sites for a target ligand with explicit consideration of protein and ligand flexibility, inspired by our previously presented flexible docking algorithm DynaDock. DynaBiS applies soft-core potentials between the ligand and the protein, thereby allowing a certain protein–ligand overlap resulting in efficient sampling of conformational adaptation effects. We evaluated DynaBiS and other commonly used binding site identification algorithms against a diverse evaluation set consisting of 26 proteins featuring peptide as well as small ligand binding sites. We show that DynaBiS outperforms the other evaluated methods for the identification of protein binding sites for large and highly flexible ligands such as peptides, both with a holo or apo structure used as input.