Apoptotic neuron-secreted HN12 inhibits cell apoptosis in Hirschsprung’s disease

Abstract

Perturbation in apoptosis can lead to Hirschsprung’s disease (HSCR), which is a genetic disorder of neural crest development. It is believed that long noncoding RNAs (lncRNAs) play a role in the progression of HSCR. This study shows that apoptotic neurons can suppress apoptosis of nonapoptotic cells by secreting exosomes that contain high levels of HN12 lncRNA. Elevated exogenous HN12 in nonapoptotic cells effectively inhibited cell apoptosis by maintaining the function of mitochondria, including the production of ATP and the release of cytochrome C. These results demonstrate that secreted lncRNAs may serve as signaling molecules mediating intercellular communication in HSCR. In addition, high HN12 levels in the circulation worked as a biomarker for predicting HSCR, providing a potential, novel, noninvasive diagnostic approach for early screening of HSCR.

Keywords:

• Hirschsprung’s disease
• neuronal development
• exosomal long noncoding RNA
• intercellular communication
• apoptosis
• mitochondria

Supplementary materials

Figure S1 H₂O₂ can induce cell apoptosis and HN12 has no matter with cell migration and proliferation.

Notes: (A) Cell proliferation and migration were not changed by treatment with siRNA against HN12. Cell viability presented as mean ± SEM (right panel), and the representative images show the invasive cells at the bottom of the membrane stained with crystal violet (left panel). (B) The expression levels of MFN1 and PPARGC1A were detected in HSCR tissues and control tissues. ***P<0.001. (C) Apoptosis analysis was conducted with SY5Y cells that were treated with H₂O₂ at 400 and 800 µM with or without 15% FBS. (D) Morphology of cells treated with H₂O₂. SH-SY5Y cells were treated for 24 hours, harvested, stained with Hoechst, and examined by confocal microscopy. All tests performed three times and results presented as mean ± SEM.

Abbreviations: siRNA, small interfering RNA; SEM, standard error of mean; HSCR, Hirschsprung’s disease; FBS, fetal bovine serum; DMEM, Dulbecco’s Modified Eagle’s Medium.

Table S1 Sequences of primers for quantitative real-time polymerase chain reaction and small interfering RNA-related sequence

Acknowledgments

The authors thank Dr Jie Zhang, Huan Chen, and Changgui Lu (Nanjing Children’s Hospital Affiliated to Nanjing Medical University) for sample collection. This study was supported by the Natural Science Foundation of China (NSFC 81370473, 81400574, 81570467), Natural Science Foundation of Jiangsu Province of China (BK20131388), and Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).

Disclosure

The authors report no conflicts of interest in this work.