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The interactions between carbon nanotubes (CNTs) and proteins were considered much attention. Advanced CNT applied biomolecules require mutual understanding of their interactions with biological molecules. Enhanced biomedical applications of CNTs have necessitated the need for the understanding their interaction with biomolecules. Non-covalent interactions of blood peptides, such as hepcidin, with carbon nanotubes, have important effects in a wide range of biological applications that are detected by analyzing the thermodynamic parameters of the interaction between CNTs and peptides. In addition, the effects of different parameters in order to evaluate how the interaction of CNTs with peptide affects and structural changes and stability of peptides were studied. In this study, based on molecular dynamics (MD) simulation, the structural changes of hepcidin 20 in interaction with multi walled carbon nanotubes (MWCNTs-COOH ) were investigated. The simulation results revealed that carbon nanotubes cause to loose the hepcidin structure and make structural changes in this peptide. On the other hand, the loose of the hepcidin structure may lead to a change in its activity. The results indicated that significant changes were made in the structure of hepcidin 20 in the presence of carbon nanotubes. The difference of parameter amounts calculated in heptidine 20 is related to their N-terminal, and loop regions.  

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Objective: Because of the importance iron metabolism and role of hepcidin in running, the present study investigates the effects of one event of submaximal exercise on plasma hepcidin concentrations in male runners. Methods: For this purpose, we selected eight runners who were athletic team members of Mazandaran University with an average age of 21.7±1.34 years, height of 175.6±5.88 cm, weight of 71.7±11.13 kg and BMI of 23.2±2.95 kg/m². Subjects ran on the treadmill at 65% heart rate reserves for 60 min and blood samples were taken before, immediately after, and at 3 and 24 h following exercise. Plasma samples were analyzed to determine the concentrations of hepcidin, IL-6, iron and ferritin. The repeated measures ANOVA with post hoc LSD were used to compare the differences between the samples. Results: The results showed significant decrease in plasma hepcidin at 24 h postexercise compared to immediately postexercise (P<0.05), which might be attributed to a significant decrease in plasma concentrations of IL-6 at 3 h postexercise (P<0.05; r=0.794). Although there were no significant differences observed in postexercise plasma iron, a dramatic increase in plasma ferritin was observed immediately, 3 and 24 h postexercise compared to pre-exercise (P<0.05). Conclusions: With regards to the lack of correlation between plasma concentrations of hepcidin and iron (P>0.05), it can be concluded that one event of submaximal exercise does not cause significant differences on plasma hepcidin concentration immediately postexercise and it does not change in regulation of iron metabolism. This observation may be related to exercise duration and intensity.