Microsized inflammaging protects stem cells - PubMed (original) (raw)

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Microsized inflammaging protects stem cells

Ryan M O'Connell et al. Blood. 2020.

Abstract

In this issue of Blood, Grants et al have identified connections between reduced expression of microRNA-146a (miR-146a), increased inflammation, impaired hematopoietic stem cell (HSC) quiescence, and a poor prognosis for acute myeloid leukemia (AML). miR-146a was originally identified as an anti-inflammatory microRNA that targets signaling proteins, which mediate inflammatory responses., Deletion of miR-146a in mice phenocopies many aspects of age-dependent inflammation,, termed “inflammaging.”

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Conflict of interest statement

Conflict-of-interest disclosure: The authors declare no competing financial interests.

Conflict-of-interest disclosure: The authors declare no competing financial interests.

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Proposed model: as a consequence of inflammaging, miR-146a levels are reduced, and inflammatory cytokine production is increased in hematopoietic cells, including macrophages. Consequently, these cytokines promote HSC proliferation and differentiation into stem cells with a myeloid and, potentially, leukemic bias. This state contributes to malignant transformation by some cell clones. Upon transformation to AML, miR-146a expression negatively correlates with prognosis.

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References

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