MiRNA in innate immune responses: novel players in wound inflammation

Chronic wounds represent a major and rising socioeconomic threat affecting over 6.5 million people in the United States costing in excess of US $25 billion annually. Wound healing is a physiological response to injury that is conserved across tissue systems. In humans, wounding is followed by instant response aimed at hemostasis, which in turn provides the foundation for inflammatory processes that closely follow. Inflammation is helpful and a prerequisite for healing as long as it is mounted and resolved in a timely manner. Chronic inflammation derails the healing cascade resulting in impaired wound closure. Disruption of Dicer, the RNase III enzyme that generates functional miRNAs, has a major impact on the overall immune system. Emerging studies indicate that miRNAs, especially miR-21, miR-146a/b, and miR-155, play a key role in regulating several hubs that orchestrate the inflammatory process. Direct evidence from studies addressing wound inflammation being limited, the current work represents a digest of the relevant literature that is aimed at unveiling the potential significance of miRNAs in the regulation of wound inflammation. Such treatment would help establish new paradigms highlighting a central role of miRs in the understanding and management of dysregulated inflammation as noted in conjunction with chronic wounds.