Table 2.
MiRNAs dysregulated in ASD and identified in animal models.
| miRNA | Function | Reference | Models |
|---|---|---|---|
| miRNA-125b | miRNA-125b regulates the expression of FMR1; it is upregulated with the FMR1 Knock-out. It contributes to the alteration of synaptic plasticity as in FXS. | [55] | KO mice |
| miRNA-132 | miRNA-132 and miRNA-125b are involved in synaptic plasticity. Furthermore, miRNA-132 targets the 3’UTR sequence of MECP2 and prevents its expression. As a result of the pain, it is downregulated, inducing an increase in the analgesic response and in the expression of MECP2. Furthermore, it is involved through the p-CREB/miR-132 pathway in the regulation of expression between PTEN and MECP2. | [55,60,61] | KO mice |
| miRNA-146a, miRNA-146b | miRNA-146a and miRNA-146b were observed in the RTT syndrome. A study on the MECP2-KO mice model observed that they are downregulated by inducing overexpression of the IRAK1 gene which leads to an inflammatory state of the brain tissue such as in ASD. | [57,58,59] | KO mice |
| miRNA-137 | When miRNA-137 is downregulated, it influences the expression of many genes implicated in neurodevelopment. This means they lead to learning and memory deficits, and they are therefore associated with ASD. Furthermore, miRNA-137 is associated with SHANK2, as both are expressed in synapses. miRNA-137 targets the 3’UTR sequence of SHANK2 so as to repress the expression of the SHANK2 protein. | [61,62,63] | KO mice |
| miRNA-134 | The KO of UBE3A allowed observing an upregulation of miRNA-134 by belonging to the miRNA379-410 cluster that regulates synaptic plasticity. Furthermore, the UBE3A1 RNA transcript acts as a rival endogenous dendritic RNA for miRNA379-410. | [65] | KO mice |
| miRNA-134-5p | miRNA-134-5p is overexpressed in the brains of patients with ASD; it controls the development of the spine. | [66,67] | VPA rats |
| miRNA-138-5p | miRNA138-5p is implicated in the development changes of dendritic spines and in the narrowing of the spine. | [66,67] | VPA rats |
| miRNA-34a | VPA regulates miRNA-34a levels which in turn regulate BCL2 expression. In the cerebral cortex of VPA rats immediately after birth, the upregulation of miRNA-34a and a reduction in BCL2 expression were observed. | [68] | VPA rats |
| miRNA-181c | miRNA-181c is upregulated in the amygdala of ASD patients; its function is associated with the development of the nervous system. | [69,70,71] | VPA rats |
| miRNA-30d | miRNA-30d is also upregulated in VPA rats, and its function is associated with the development of the nervous system. | [69,70,71] | VPA rats |