Discovery of therapeutic targets for spinal cord injury based on molecular mechanisms of axon regeneration after conditioning lesion

Multi-omics reveal the role of nociception-related genes TNXB, CTNND1 and CBL in depression

BACKGROUND

Recent studies have suggested a link between nociception and depression. However, the specific genes involved remain unclear.

METHODS

This study investigates this genetic link using multi-omics data. We collected nociception-related genes from the GeneCards database and integrated quantitative trait loci (mQTLs, eQTLs and pQTLs) data for gene expression, DNA methylation and protein expression. GWAS data from the IEU database served as the discovery cohort for depression, with FinnGen and GWAS Catalog data used for validation. Summary data-based Mendelian Randomization (SMR) analysis was employed to examine the interactions between nociception-related genes and depression, and colocalization analysis identified shared causal variants. The associations between depression and target gene expression in specific tissues and specific cell types were assessed using the GTEx v8 dataset and single-cell eQTL data.

RESULTS

SMR analysis revealed 215 mQTLs, 12 eQTLs, and 1 pQTL associated with depression in the discovery cohort. By integrating multi-omics evidence, we found that the hypermethylation of the TNXB gene (cg02272968, cg02432444, cg27624229) and the hypomethylation of the CTNND1 gene (cg16127573) and the P2RY6 gene (cg12889420) were found to upregulate their expression, potentially increasing the risk of depression. GTEx eQTL analysis confirmed CBL expression in the substantia nigra positively correlates with depression risk. However, none of the key genes were confirmed in the single-cell eQTL analysis.

CONCLUSIONS

Our study emphasizes the importance of nociception-related genes, particularly TNXB, CTNND1 and CBL in the pathogenesis of depression. Future research should build on these findings for potential prevention and treatment strategies.

HIF-1α Induced by Hypoxia Promotes Peripheral Nerve Injury Recovery Through Regulating Ferroptosis in DRG Neuron

Peripheral nerve injury (PNI) usually has a poor effect on functional recovery and severely declines the patient's quality of life. Our prior findings indicated that hypoxia remarkably promoted nerve regeneration of rats with sciatic nerve transection. However, the underlying molecular mechanisms of hypoxia in functional recovery of PNI still remain elusive. In this research, we tried to explain the functional roles and mechanisms of hypoxia and the hypoxia-inducible factor-1α (HIF-1α) in PNI. Our results indicated that hypoxia promoted proliferation and migration of dorsal root ganglia (DRG) and increased the expression of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). Mechanistically, hypoxia suppressed ferroptosis through activating HIF-1α in DRG neurons. Gain and loss of function studies were performed to evaluate the regulatory roles of HIF-1α in ferroptosis and neuron recovery. The results revealed that up-regulation of HIF-1α enhanced the expression of solute carrier family membrane 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) and increased the contents of cysteine and glutathione, while inhibiting the accumulation of reactive oxygen species (ROS). Our findings provided novel light on the mechanism of ferroptosis involved in PNI and manifest hypoxia as a potential therapeutic strategy for PNI recovery.