Altered Morphologies and Functions of the Olfactory Bulb and Hippocampus Induced by miR-30c

Abstract

Adult neurogenesis is considered to contribute to a certain degree of plasticity for the brain. However, the effects of adult-born neurons on the brain are still largely unknown. Here, we specifically altered the expression of miR-30c in the subventricular zone (SVZ) and dentate gyrus (DG) by stereotaxic injection with their respective up- and down-regulated lentiviruses. Results showed an increased level of miR-30c enhanced adult neurogenesis by prompting cell-cycles of stem cells, whereas down-regulated miR-30c led to the opposite results. When these effects of miR-30c lasted for 3 months, we detected significant morphological changes in the olfactory bulb (OB) and lineage alteration in the hippocampus. Tests of olfactory sensitivity and associative and spatial memory showed that a certain amount of adult-born neurons are essential for the normal functions of the OB and hippocampus, but there also exist redundant newborn neurons that do not further improve the functioning of these areas. Our study revealed the interactions between miRNA, adult neurogenesis, brain morphology and function, and this provides a novel insight into understanding the role of newborn neurons in the adult brain.

Brain-Derived Extracellular Vesicle microRNA Signatures Associated with In Utero and Postnatal Oxycodone Exposure

“…Among the downregulated BDEs miRNAs in the IUO offspring, which included miRs-30c-1 (-0.17 fold), 384-5p (-1.56 fold), and 195-5p (-1.54 fold), miR-30c-1 downregulation is associated with a decrease in adult neurogenesis [61,62] as well as temporal lobe epilepsy in the latent phase in the rat pilocarpine model [63]. Downregulation of miR-384-5p has been shown to affect long-term synaptic and spine plasticity [64].…”

Apoptosis, rather than neurogenesis, induces significant hippocampal‐dependent learning and memory impairment in chronic low Cd2+ exposure

“…Immunofluorescence was assessed according to the standard procedure 27 . In brief, the half hippocampus was cut into 4 continuous set of sagittal sections, sections were treated with 10 mM sodium citrate for antigen‐retrieval, then incubated with the blocking and permeabilization solution (PBS containing 0.2% Triton X‐100 and 5% donkey serum) for 40 min at room temperature and incubated overnight at 4°C.…”

Emerging Role of MicroRNA-30c in Neurological Disorders

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