Inflammatory diets are associated with lower total iron binding capacity in sera of young adults

Assessment of iron status

PURPOSE OF REVIEW

Iron is an essential trace element in human health that can be harmful at abnormal levels such as iron overload or deficiency. Measured iron status in the body can depend on health outcomes experienced by the individual and this can complicate its accurate assessment. This review will highlight recent research on iron assessment in the literature.

RECENT FINDINGS

Research on iron assessment within the past 18 months included some common themes spanning new methods and biomarkers, as well as existing problems in assessing iron deficiency and overload. Heterogeneity in associations between inflammation and iron levels are reflected across different inflammatory biomarkers. New methods relevant to low- and high-resource settings may improve assessment in tissues with iron deficiency and overload. Consensus papers outlined best practices when using MRI to assess iron status. Outside of newer methods, traditional serum markers are the subject of a call for updated guidance when assessing iron status.

SUMMARY

Research continues on the topic of iron assessment, underlying its complex metabolism in the body and resulting challenges in assessment. Current literature underscores progress to make iron assessment more accessible, improve existing methods, and update current assessment methods so they correspond with recent research to improve human health.

Induction of Hepcidin Expression in the Renal Cortex of Sickle Cell Disease Mice

In patients with sickle cell disease (SCD), chronic hemolysis and frequent blood transfusions cause iron overload and accumulation in the kidneys. The iron deposition is found in the renal cortex and correlates with the severity of hemolysis. In this study, we observed a significant accumulation of iron in the renal cortex of a mouse model of SCD, and assessed the expression of the proteins involved in maintaining renal iron homeostasis. Despite the intracellular iron accumulation, the levels of the transferrin receptor in the kidneys were increased, but the levels of the iron exporter ferroportin were not altered in SCD mice. Ferroportin is regulated by hepcidin, which binds to it and promotes its degradation. We found reduced serum hepcidin levels but increased renal hepcidin production in SCD mice. Furthermore, we observed significant macrophage infiltration and increased expression of intercellular adhesion molecule 1 in the endothelial cells of the kidneys in SCD mice. These observations correlated with elevated levels of proinflammatory cytokines IL-1β and IL-6, which can potentially stimulate hepcidin expression. Taken together, our results demonstrate that in individuals with SCD, a renal inflammation state induces renal hepcidin production that blocks the upregulation of ferroportin levels, resulting in dysregulation of iron homeostasis in the kidney and iron deposition in the renal cortex.