Identification of putative pathogenic SNPs implied in schizophrenia-associated miRNAs

An In Vitro Study for the Role of Schizophrenia-Related Potential miRNAs in the Regulation of COMT Gene

This study aimed to analyze the possible association of miR-30a-5p, miR-30e-5p, and miR-34a-5p identified as potential candidate miRNAs in schizophrenia, with the COMT gene. Candidate miRNAs were obtained from the TargetScan database. The SH-SY5Y human neuroblastoma cell line was used as a cellular model for schizophrenia. miR-30a-5p, miR-30e-5p, and miR-34a-5p mimics were transfected into the SH-SY5Y cell line. Total RNA was isolated from transfected cells and RNA-IP samples and reverse transcripted for miRNA and mRNA analysis. RT-qPCR and western blot were performed to observe changes in expression levels of COMT. RNA-ımmunoprecipitation was performed to determine RNA-protein interactions after mimic transfection. In the study, it was observed that COMT gene expression levels decreased significantly after miR-30a-5p and miR-34a-5p expressions, whereas increased significantly as a result of miR-30e-5p transfection. RNA-IP data have shown that the amount of COMT pulled down by Ago2 was increased after miR-30a-5p and miR-34a-5p transfections. RNA-IP results revealed that miR-30a-5p and miR-34a-5p are direct targets for the COMT gene.

The Biomarker and Therapeutic Potential of Circular Rnas in Schizophrenia

Circular RNAs (circRNAs) are endogenous, single-stranded, most frequently non-coding RNA (ncRNA) molecules that play a significant role in gene expression regulation. Circular RNAs can affect microRNA functionality, interact with RNA-binding proteins (RBPs), translate proteins by themselves, and directly or indirectly modulate gene expression during different cellular processes. The affected expression of circRNAs, as well as their targets, can trigger a cascade of events in the genetic regulatory network causing pathological conditions. Recent studies have shown that altered circular RNA expression patterns could be used as biomarkers in psychiatric diseases, including schizophrenia (SZ); moreover, circular RNAs together with other cell molecules could provide new insight into mechanisms of this disorder. In this review, we focus on the role of circular RNAs in the pathogenesis of SZ and analyze their biomarker and therapeutic potential in this disorder.

Nociceptive related microRNAs and their role in rheumatoid arthritis

Rheumatoid Arthritis (RA) is an autoimmune disease with unknown etiology and a global incidence around 1%, a positive family history increases the risk of RA roughly three to five times. Pain is one of the first symptoms to appear in this disease. MicroRNAs (miRNAs) belong to the class of small non-coding RNAs; they regulate multiple cellular processes including embryonic development, cellular proliferation, differentiation and apoptosis among others. A great deal of evidence points to the employment of miRNAs as therapeutic targets and biomarkers for several pathologies. The main objective of this Review is to assess how miRNAs participate in the pathogenesis of RA. Two advanced searches were conducted in databases, one using "micro-RNA" and "rheumatoid arthritis" as key words, and another one with "micro-RNA", "pain" and "nociception". In this Review, we describe how six miRNAs: miR-16-5p, miR-23b-3b, miR-124-3p, miR-146a-5p, miR-155-5p and miR-223-3p, involved in the modulation and transmission of the nociceptive input are unregulated in RA patients. Key molecular pathways involved in nociception, inflammation and autoimmune responses, are regulated by these miRNAs; the NF-κB, TNF-α, interleukins and TLR4. By means of gene repression, the miRNAs here described modulate the nociceptive process as well as the autoimmune response that characterize this disease.

The microRNA cluster miR-183/96/182 contributes to long-term memory in a protein phosphatase 1-dependent manner

Memory formation is a complex cognitive function regulated by coordinated synaptic and nuclear processes in neurons. In mammals, it is controlled by multiple molecular activators and suppressors, including the key signalling regulator, protein phosphatase 1 (PP1). Here, we show that memory control by PP1 involves the miR-183/96/182 cluster and its selective regulation during memory formation. Inhibiting nuclear PP1 in the mouse brain, or training on an object recognition task similarly increases miR-183/96/182 expression in the hippocampus. Mimicking this increase by miR-183/96/182 overexpression enhances object memory, while knocking-down endogenous miR-183/96/182 impairs it. This effect involves the modulation of several plasticity-related genes, with HDAC9 identified as an important functional target. Further, PP1 controls miR-183/96/182 in a transcription-independent manner through the processing of their precursors. These findings provide novel evidence for a role of miRNAs in memory formation and suggest the implication of PP1 in miRNAs processing in the adult brain.

Curcumin improves bone microarchitecture in glucocorticoid-induced secondary osteoporosis mice through the activation of microRNA-365 via regulating MMP-9

The present study aimed to investigate bone microarchitecture of the proximal tibia in glucocorticoid-induced osteoporosis (GIOP) mice, and the underlying molecular mechanisms of curcumin in DXM-induced osteoporosis were performed. DXM-treated facilitated to induce hypercalciuria in mice, and curcumin-treated showed a decrease in urine calcium. Curcumin reversed DXM-induced bone resorption, including an increase in serum OCN and a decrease in bone resorption markers CTX and TRAP-5b. H&E staining showed the increased disconnections and separation in trabecular bone network as well as the reduction of trabecular thickness throughout the proximal metaphysis of tibia in GIOP group. Importantly, curcumin reversed DXM-induced trabecular deleterious effects and stimulated bone remodeling. The further evidence showed that curcumin supplement significantly decreased the TRAP-positive stained area and inhibited the activity of OPG/RANKL/RANK signaling in the GIOP mice. Moreover, bioinformatics analysis suggested that miR-365 was a regulator of MMP9. The levels of miR-365 were markedly suppressed; however, curcumin treatment could reverse the downregulation of miR-365 in the tibia of GIOP mice. Simultaneously, the results demonstrated that the mRNA and protein expression of MMP-9 were significantly increased in GIOP mice compared with that of the control group. Curcumin treatment could suppress the expression of MMP-9 in the tibia of GIOP mice. The present study demonstrated the protective effects of curcumin against bone deteriorations in the experimentally DIOP mice, and the underlying mechanism was mediated, at least partially, through the activation of microRNA-365 via suppressing MMP9.

Two Mutations in the Caprine MTHFR 3'UTR Regulated by MicroRNAs Are Associated with Milk Production Traits

BACKGROUND

5,10-Methylenetetrahydrofolate reductase (MTHFR) plays a central role in folate metabolism by irreversibly converting 5,10-methylenetetrahydrofolate to 5-methylenetetrahydrofolate, a predominant circulating form of folate. Folate is reportedly important for milk protein synthesis, and MTHFR may be a key regulatory point of folate metabolism for milk protein synthesis in mammary epithelial cells. Prior to this study, polymorphisms of the MTHFR gene were not associated with milk production traits from a breeding perspective. Single nucleotide polymorphisms (SNPs) at microRNA (miRNA) binding sites (miR-SNPs) can affect gene expression. This study aimed to identify the effects of miR-SNPs (g.2244A>G and g.2264A>G) in the caprine MTHFR 3' UTR on the milk production traits of dairy goats.

RESULTS

Guanzhong dairy (GD, n = 325) goats were used to detect SNPs in the caprine MTHFR 3' UTR by DNA sequencing. Two novel SNPs (g.2244A>G and g.2264A>G) were identified in the said region. The homozygous haplotype A-G of the SNPs g.2244A>G and g.2264A>G was significantly associated with milk yield and milk protein levels in GD goats (P < 0.05). Functional assays indicated that the MTHFR 2244 A → G substitution could increase the binding activity of hsa-miR-1266 with the MTHFR 3' UTR. The MTHFR 2264 A → G substitution could decrease the binding activity of hsa-miR-616 with the MTHFR 3' UTR. In addition, we observed a significant increase in the MTHFR mRNA levels of homozygous haplotype A-G carriers relative to those of homozygous haplotype G-A carriers. These results indicated that both SNPs altered the MTHFR mRNA levels. These altered levels of MTHFR mRNA may account for the association of SNPs with milk production traits.

CONCLUSIONS

This study is the first to report that the g.2244A>G and g.2264A>G polymorphisms were associated with milk production traits in GD goats. Further investigations should explore the underlying miRNA-mediated mechanisms that are modified by the g.2244A>G and g.2264A>G SNPs. The current study evaluated these SNPs as potential genetic markers in goats, with potential applications in breeding programs.