Table 1.
miRNAs involved in the electrical and structural changes in atrial fibrillation.
| miRNAs | Target genes | Effect | Roles | References |
|---|---|---|---|---|
| miR-1 | KCNJ2 | Increased Ik1 | Down-regulation in AF | (106, 107) |
| GJA1/ connexin43 | Slower conduction | *Atrial electrical remodeling | (108) | |
| HCN2 | Amplified automaticity | *Ectopic activity | (109) | |
| HSP60, HSP70 | Favors apoptosis | *Atrial structural remodeling | (110) | |
| miR-21 | Spry1, | Up-regulated | Inhibits fibroblast proliferation | (111) |
| PDCD4 | Anti-apoptosis | (78, 112) | ||
| miR-26 | KCNJ2/Kir21 | Down-regulated | Increases Ik1 | (113, 114) |
| Atrial electrical remodeling | APD shortening | (79, 114) | ||
| miR-29 | Fibrillin Collagen 1A1, Collagen 3A1 |
Down-regulated | Increased fibrosis | (115) |
| Mcl-2 | *atrial structural remodeling | Pro-apoptosis | (100) | |
| miR-30 | CTGF | Down-regulated | Increased fibrosis Matrix remodeling | (110, 116) |
| miR-133 | CTGF | Down-regulated | Increased fibrosis | (116, 117) |
| *Ectopic activity | Matrix remodeling | |||
| TGF-b1 TGFbRII | Atrial structural remodeling | Anti-fibrosis | (118) | |
| HCN2 HCN4 | Enhanced automaticity | Down-regulation in AF | (109) | |
| Caspase 9 | Anti-apoptosis | (110) | ||
| miR-208 | THRAP1 | *Pro-fibrosis | Atrial structural remodeling | (119) |
| miR-328 | Up-regulated | CACNB1, CACNA1C | Shorter atrial action potential duration | (105) |
| Atrial electrical remodeling | APD shortening | (120) | ||
| miR-499 | KCNN3 | Up-regulated | Altered conduction | (121) |
| miR-590 | TGF-b1 TGFbRII |
Down-regulated in AF | Anti-fibrosis Atrial structural remodeling |
(118) |
AF, atrial fibrillation; KCNJ2, K+ inwardly-rectifying channel, subfamily J, member 2; Ik1, inward-rectifier K+ current; GJA1, Gap junction alpha1 protein; HCN, hyperpolarization-activated cAMP-gated non-selective cation channel; HSP, heat shock protein; SPRY1, sprouty homolog 1; PDCD4, programmed cell death 4; APD, atrial potential duration; Mcl-2, myeloid cell leukemia 2 (an anti-apoptotic Bcl-2 family member); CTGF, connective tissue growth factor; TGF b, transforming growth factor b; THRAP1, co-regulator of the thyroid hormone receptor; CACNB1, cardiac IcaL channel beta1 subunit; CACNA1C, cardiac IcaL channel alpha1c subunit; KCNN3, K+ intermediate/small conductance Ca2+ activated channel;
speculations, which need further experimental studies; A-ER, atrial electrical remodeling; A-SR, atrial structural remodeling.