| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Fischer, C.P, et al.
(författare)
-
Vitamin E isoform-specific inhibition of the exercise-induced heat shock protein 72 expression in humans
- 2006
-
Ingår i: Journal of applied physiology. - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 100:5, s. 1679-1687
-
Tidskriftsartikel (refereegranskat)abstract
- Increased levels of reactive oxygen and nitrogen species, as seen in response to exercise, challenge the cellular integrity. Important protective adaptive changes include induction of heat shock proteins (HSPs). We hypothesized that supplementation with antioxidant vitamins C (ascorbic acid) and E (tocopherol) would attenuate the exercise-induced increase of HSP72 in the skeletal muscle and in the circulation. Using randomization, we allocated 21 young men into three groups receiving one of the following oral supplementations: RRR-α-tocopherol 400 IU/ day + ascorbic acid (AA) 500 mg/day (CEα), RRR-α-tocopherol 290 IU/day + RRR-γ-tocopherol 130 IU/day + AA 500 mg/day (CEαγ), or placebo (Control). After 28 days of supplementation, the subjects performed 3 h of knee extensor exercise at 50% of the maximal power output. HSP72 mRNA and protein content was determined in muscle biopsies obtained from vastus lateralis at rest (0 h), postexercise (3 h), and after a 3-h recovery (6 h). In addition, blood was sampled for measurements of HSP72, α-tocopherol, γ-tocopherol, AA, and 8-isoprostaglandin-F2α (8-PGF2α). Postsupplementation, the groups differed with respect to plasma vitamin levels. The marker of lipid peroxidation, 8-iso-PGF2α, increased from 0 h to 3 h in all groups, however, markedly less (P < 0.05) in CEα. In Control, skeletal muscle HSP72 mRNA content increased 2.5-fold (P < 0.05) and serum HSP72 protein increased 4-fold (P < 0.05) in response to exercise, whereas a significant increase of skeletal muscle HSP72 protein content was not observed (P = 0.07). In CEα, skeletal muscle HSP72 mRNA, HSP72 protein, and serum HSP72 were not different from Control in response to exercise. In contrast, the effect of exercise on skeletal muscle HSP72 mRNA and protein, as well as circulating HSP72, was completely blunted in CEαγ. The results indicate that γ-tocopherol comprises a potent inhibitor of the exercise-induced increase of HSP72 in skeletal muscle as well as in the circulation.
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Kallner Bastviken, Sofia, et al.
(författare)
-
Effects of vegetation and hydraulic load on seasonal nitrate removal in treatment wetlands
- 2009
-
Ingår i: Ecological Engineering. - Amsterdam : Elsevier. - 0925-8574 .- 1872-6992. ; 35:5, s. 946-952
-
Tidskriftsartikel (refereegranskat)abstract
- Optimising nitrate removal and identifying critical factors for nitrate removal in wetlands is an important environmental task in the effort to achieve better surface water quality. In this study, eighteen free water surface wetlands with similar shape and size (22 m2 each) received groundwater with a high nitrate-N concentration (about 11 mg l−1). The effects of two hydraulic loads, 0.13 m d−1 and 0.39 m d−1, and three vegetation types – emergent, submersed and freely developing vegetation – on the nitrate-N removal were investigated through mass inflow and outflow measurements.No significant difference in nitrate removal between the different hydraulic loads could be detected. Significantly higher area-specific nitrate removal and first-order area-based rate coefficients were found in the basins with emergent vegetation, with no difference between the basins with submersed and freely developing vegetation. The nitrate-N removal increased as the wetlands matured and the vegetation grew denser, emphasizing the role of dense emergent vegetation for nitrate removal at high nitrate concentrations.
|
|
