This study was aimed at investigating the differentially expressions of long noncoding RNAs (lncRNAs) and mRNAs in the brains of a middle cerebral artery occlusion/reperfusion (MCAO/R) group and a MCAO/R + 20(R)-Rg3 group. Biological enrichment analysis was performed, and a lncRNA-mRNA coexpression network was constructed, to reveal the targets and pathways of 20(R)-Rg3 involved in the regulation of cerebral ischemia-reperfusion injury (CIRI). The RNA-seq high-throughput sequencing method was employed to detect differentially-expressed genes between the groups, which were verified by RT-PCR. Functional enrichment analyses of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway were performed to explore the biological functions and relevant pathways. The coexpression network of the screened lncRNAs and mRNAs was built by using Cytoscape software. The results identified 77 upregulated lncRNAs, 162 downregulated lncRNAs, 66 upregulated mRNAs and 472 downregulated mRNAs in the MCAO/R + 20(R)-Rg3 group, compared with those in the MCAO/R group. GO enrichment analysis showed that the GO terms were mainly enriched in stimulation response, cellular response, and stress response. KEGG pathways were mainly related to the tumor necrosis factor (TNF), NF-κB, cytokine, and other receptor signaling pathways. In addition, the coexpression analysis between lncRNA and mRNA identified 314 nodes and 515 connections between 6 lncRNAs and 308 mRNAs, of which 511 were positive and 4 were negative. Among them, ENSRNOG-00000059555 was strongly correlated with AABR07001160.1. This study revealed multiple lncRNAs were involved in the neuroprotection of 20(R)-Rg3 against CIRI and thereby provided new insights into the use of 20(R)-Rg3 as a novel neuro protectant in ischemic stroke management.

MicroRNAs (miRNAs) are a class of small, endogenous, noncoding RNAs. Recent research has proven that miRNAs play an essential role in the occurrence and development of ischemic stroke. Our previous studies confirmed that 20(R)-ginsenosideRg3 [20(R)-Rg3] exerts beneficial effects on cerebral ischemia–reperfusion injury (CIRI), but its molecular mechanism has not been elucidated. In this study, we used high-throughput sequencing to investigate the differentially expressed miRNA and mRNA expression profiles of 20(R)-Rg3 preconditioning to ameliorate CIRI injury in rats and to reveal its potential neuroprotective molecular mechanism. The results show that 20(R)-Rg3 alleviated neurobehavioral dysfunction in MCAO/R-treated rats. Among these mRNAs, 953 mRNAs were significantly upregulated and 2602 mRNAs were downregulated in the model group versus the sham group, whereas 437 mRNAs were significantly upregulated and 35 mRNAs were downregulated in the 20(R)-Rg3 group in contrast with those in the model group. Meanwhile, the expression profile of the miRNAs showed that a total of 283 differentially expressed miRNAs were identified, of which 142 miRNAs were significantly upregulated and 141 miRNAs were downregulated in the model group compared with the sham group, whereas 34 miRNAs were differentially expressed in the 20(R)-Rg3 treatment group compared with the model group, with 28 miRNAs being significantly upregulated and six miRNAs being significantly downregulated. Furthermore, 415 (391 upregulated and 24 downregulated) differentially expressed mRNAs and 22 (17 upregulated and 5 downregulated) differentially expressed miRNAs were identified to be related to 20(R)-Rg3′s neuroprotective effect on stroke recovery. The Kyoto Encyclopedia of Genes and Genomes (KEGG) results showed that 20(R)-Rg3 could modulate multiple signaling pathways related to these differential miRNAs, such as the cGMP-PKG, cAMP and MAPK signaling pathways. This study provides new insights into the protective mechanism of 20(R)-Rg3 against CIRI, and the mechanism may be partly associated with the regulation of brain miRNA expression and its target signaling pathways.