The m6A methylation and expression profiles of mouse neural stem cells after hypoxia/reoxygenation.

BACKGROUND: Ischemia-reperfusion injury to the central nervous system often causes severe complications. The activation of endogenous neural stem cells (NSCs) is considered a promising therapeutic strategy for nerve repair. However, the specific biological processes and molecular mechanisms of NSC activation remain unclear, and the role of N6-methyladenosine (m6A) methylation modification in this process has not been explored. METHODS: NSCs were subjected to hypoxia/reoxygenation (H/R) to simulate ischemia-reperfusion in vivo. m6A RNA methylation quantitative kit was used to measure the total RNA m6A methylation level. Quantitative real-time PCR was used to detect methyltransferase and demethylase mRNA expression levels. Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and RNA sequencing (RNA-seq) were conducted for NSCs in control and H/R groups, and the sequencing results were analyzed using bioinformatics. Finally, the migration ability of NSCs was identified by wound healing assays, and the proliferative capacity of NSCs was assessed using the cell counting kit-8, EdU assays and cell spheroidization assays. RESULTS: Overall of m6A modification level and Mettl14 mRNA expression increased in NSCs after H/R treatment. The m6A methylation and expression profiles of mRNAs in NSCs after H/R are described for the first time. Through the joint analysis of MeRIP-seq and RNA-seq results, we verified the proliferation of NSCs after H/R, which was regulated by m6A methylation modification. Seven hub genes were identified to play key roles in the regulatory process. Knockdown of Mettl14 significantly inhibited the proliferation of NSCs. In addition, separate analysis of the MeRIP-seq results suggested that m6A methylation regulates cell migration and differentiation in ways other than affecting mRNA expression. Subsequent experiments confirmed the migration ability of NSCs was suppressed by knockdown of Mettl14. CONCLUSION: The biological behaviors of NSCs after H/R are closely related to m6A methylation of mRNAs, and Mettl14 was confirmed to be involved in cell proliferation and migration.

miR-872-5p/FOXO3a/Wnt signaling feed-forward loop promotes proliferation of endogenous neural stem cells after spinal cord ischemia-reperfusion injury in rats.

The activation of endogenous neural stem cells (NSCs) is considered an important mechanism of neural repair after mechanical spinal cord injury; however, whether endogenous NSC proliferation can also occur after spinal cord ischemia-reperfusion injury (SCIRI) remains unclear. In this study, we aimed to verify the existence of endogenous NSC proliferation after SCIRI and explore the underlying molecular mechanism. NSC proliferation was observed after SCIRI in vivo and oxygen-glucose deprivation and reperfusion (OGD/R) in vitro, accompanied by a decrease in forkhead box protein O 3a (FOXO3a) expression. This downward trend was regulated by the increased expression of microRNA-872-5p (miR-872-5p). miR-872-5p affected NSC proliferation by targeting FOXO3a to increase the expression of ß-catenin and T-cell factor 4 (TCF4). In addition, TCF4 in turn acted as a transcription factor to increase the expression level of miR-872-5p, and knockdown of FOXO3a enhanced the binding of TCF4 to the miR-872-5p promoter. In conclusion, SCIRI in vivo and OGD/R in vitro stimulated the miR-872-5p/FOXO3a/ß-catenin-TCF4 pathway, thereby promoting NSC proliferation. At the same time, FOXO3a affected TCF4 transcription factor activity and miR-872-5p expression, forming a positive feedback loop that promotes NSC proliferation.

Effect of combined epidural-general anesthesia on long-term survival of patients with colorectal cancer: a meta-analysis of cohort studies.

PURPOSE: This study aimed to analyze the long-term survival of patients with colorectal cancer after receiving combined epidural-general anesthesia (EGA) or general anesthesia (GA) alone. METHODS: The PubMed, MEDLINE, Web of Science, Cochrane Library, and Embase databases were used to search for cohort studies that explored the differences between the effects of EGA and GA on overall survival (OS) and recurrence-free survival (RFS) of patients with colorectal cancer. The hazard ratios (HRs) and their 95% confidence intervals (95%CIs) were used as indicators to evaluate the strength of the effects and were pooled. RESULTS: Nine studies were included in the meta-analysis. EGA improved the OS of patients with colorectal cancer compared with GA (HR = 0.904, 95%CI 0.871-0.938, P < 0.05). In the subgroup analysis, EGA was more protective for OS of patients with colon cancer than GA (HR = 0.840, 95%CI 0.732-0.963, P < 0.05), but not for OS of patients with rectal cancer (HR = 0.764, 95%CI 0.398-1.469, P > 0.05). Additionally, EGA could not further prolong RFS in patients with colorectal cancer (HR = 1.015, 95%CI 0.942-1.093, P > 0.05), which was the same in the subgroup analysis of patients with colon cancer (HR = 0.908, 95%CI 0.760-1.085, P > 0.05). CONCLUSION: EGA could improve the OS of patients with colorectal cancer, especially those with colon cancer, but it could not improve the OS in the subgroup of patients with rectal cancer. This difference may be due to the immune protective function of the parasympathetic nerve innervating the intestinal tubes above the splenic flexure retained by EGA. Additionally, although EGA has a protective effect on RFS in patients with colorectal cancer, the difference was not significant.  The design of this analysis is registered and displayed in the PROSPERO database (CRD42021274864).