Bess Bauer, Weber State University
Objectives We evaluated the effects of different levels of stored iron (ferritin) within normal ranges on immune cell group production and inflammation markers in cross-country athletes. Research Methodology Forty-one NCAA division 1 cross-country athletes, ages 18 to 25 years old (Male: 19; Female; 22), had blood drawn at the beginning of the cross country season. Blood was collected from subjects and analyzed by complete blood count (CBC) at McKay Dee Hospital in Ogden, Utah. Enzymatic spectrophotometry was used to determine participants ferritin levels. Cytokines IL-1β IL-6, IL10, GM-CSF, IL-5, and IL-4 were measured at baseline by the magnetic multiplex panel for Luminex TM platform (at University of Connecticut). Based on ferritin levels, participants were divided into two groups, high ferritin, and low ferritin. Student’s t-test was used to compare cytokines and CBC mean difference between low and high ferritin groups. Pearson correlations were used to determine associations between cells groups and cytokines under low or high ferritin conditions. IBM SPSS statistics 22 software for Windows was used to analyze the collected data. Results Participants in the high ferritin group had higher levels of IL-1β (p=0.04) and IL-5 (p=0.05) and eosinophils (p=0.02) when compared to the low ferritin counterparts. In contrast, IL-4 (p=0.04) was significantly higher in the low ferritin group. Moderate-strong correlations were found between eosinophils and cytokines; IL-1β (r=0.64) and IL-5 (r=0.59) in the high ferritin group. Conversely, eosinophils from the low ferritin group correlated strongly with IL-4 (r=0.86) Conclusions In this study, it was observed that eosinophils correlated with different cytokines depending on the iron storage status. Our results are in accordance with previous studies showing that IL-1β down regulates ferroportin (FPN) by increasing hepcidin levels which in turn decrease iron absorption. As iron storage in the form of ferritin increases, the need to absorb iron decreases inversely to IL-1β. Additionally, we observed increases in IL-4 in the low ferritin group. IL-4 has been observed to signal an increase in iron uptake (absorption) and mobilization. This is accomplished through transferrin (Tfn) expression. Furthermore, eosinophils and IL-5 were higher in the high ferritin group. IL-5 is a hematopoietic cytokine produced by eosinophils, it is possible that the increases in this biomarker were linked to the increases in red blood cell production observed on the high ferritin athlete group. Our results indicate that Iron storage status measured by ferritin levels may modulate cytokine release and immune cell profile.