RESUMO
Objective:To explore the relative genes that may influence kidney aging and verify the expression of clock gene Arntl in aging kidney. Methods:The differentially expressed genes between C57BL/6 male aging mice (24 months old) group and young mice (3 months old) group were identified by whole transcriptome sequencing, and the enriched biological pathways and key proteins were analyzed by bioinformatics methods. RT-qPCR and Western blotting were used to verify the mRNA and protein expression of Arntl.Results:(1) A total of 119 differentially expressed genes were screened between aging mice group and young mice group by whole transcriptome sequencing. Differentially expressed genes were mainly enriched in biological processes such as rhythmic process, circadian rhythm and circadian regulation of gene expression (all P<0.001). Protein-protein interaction analysis results showed that Nfil3, Hspa8, Arntl, Hlf, Rorc, Per3 and Npas2 and so on, were the key proteins in these differentially expressed genes. The results of RT-qPCR confirmed that the expression differences of clock genes Arntl, Nfil3, Npas2 and Per3 between aging mice group and young mice group were consistent with sequencing results (all P<0.05). (2) Compared with C57BL/6 young mice group and SAMR1 rapidly aging mice, the protein expression of Arntl in aging mice group and SAMP8 rapidly aging mice had downward trends. Conclusions:Clock genes and their circadian biological pathways may play an important role in the process of renal aging. The expression of Arntl in aging kidney has a downward trend.
RESUMO
Objective:To analyze the differentally expressed long non-coding RNA (lncRNA) among mice of different ages and explore the mechanism of kidney aging.Methods:Male C57BL/6 mice aged 3-month-old ( n=5), 12-month-old ( n=5) and 24-month-old ( n=5) (each weighting about 25 g) were randomly selected. PAS staining, Masson staining and senescence associated β-galactosidase (SA-β-gal) staining were used to detect the pathology and cell senescence of mice kidney. High throughput sequencing was performed to detect the differentially expressed lncRNA and their fragments per kilobase million. Real-time quantitative PCR was used to verify the differentially expressed lncRNA. Competitive endogenous RNA (ceRNA) network, which consisted of lncRNA, miRNA and mRNA was built. GO and KEGG enrichment analysis method were used to predict the biological function of differentially expressed lncRNA. Results:PAS staining and Masson staining showed the development of kidney fibrosis, and SA-β-gal staining positive region was increased significantly as age increased. There were 938 known lncRNA and 542 novel lncRNA differentially expressed among different ages' mouse kidney. Compared with 3-month-old mice, 33 lncRNA were up-regulated and 43 lncRNA were down-regulated in 12-month-old mice. Compared with 3-month-old mice, 130 lncRNA were up-regulated and 91 lncRNA were down-regulated in 24-month-old mice. Compared with 12-month-old mice, 36 lncRNA were up-regulated and 22 lncRNA were down-regulated in 24-month-old mice. The results of qRT-PCR about verified 10 lncRNAs with larger differential expression multiples and higer expression levels were consistent with the sequencing data. GO enrichment analysis showed that the target genes of lncRNA differentially expressed in the three groups were mostly located in the nucleus and cytoplasm, and might play a role by binding to proteins or participate in various protein phosphorylation, cell cycle, transcription, transcription regulation and other processes. KEGG enrichment analysis showed that the target genes of lncRNA differentially expressed in the three group were significantly enriched in Rap1 signaling pathway, FOXO signaling pathway and MAPK signaling pathway, which were closely related to kidney aging.Conclusion:There are significant differences in expression of lncRNA among the kidney of different ages mice, which are involved in the occurrence of renal senescence.