A study in mice demonstrated that the miR-30d-5p is a cardio-protective circulating marker released by cardiomyocytes in response to resynchronization therapy and is associated with lower mortality in heart failure patients [Kim et al. DOI:10.1038/s41598-018-33020-x]. In human plasma, the miR-30d-5p was found to be upregulated in patients with mild traumatic brain injury (TBI) compared to healthy controls, as identified in a separate study [Qin et al. DOI:10.1371/journal.pone.0204051].