The mechanism on phosphorylation of Hsp20Ser16 inhibit GA stress and ER stress during OGD/R

PLoS One. 2019 Mar 7;14(3):e0213410. doi: 10.1371/journal.pone.0213410. eCollection 2019.

Abstract

Recent research has demonstrated that small heat shock protein (sHsp) phosphorylation plays a variety of roles in neural cells. While the phosphorylation of serine 16 (Ser16) is blocked, Hsp20 no longer has neuroprotective effects. To further investigate the mechanism underlying this process, oxygen-glucose deprivation and reperfusion (OGD/R) was used with human SH-SY5Y cells and mouse N2a neuroblastoma cells. When SH-SY5Y and N2a cells were transfected with pEGFP-Hsp20(WT), pEGFP-Hsp20(S16A), and pEGFP-Hsp20(S16D) plasmids, the Golgi apparatus (GA) became more swollen and scattered, and many small fragments formed in the MOCK and S16A groups after OGD/R (P < 0.05). Meanwhile, the endoplasmic reticulum (ER) network was reduced, and the lamellar structure increased. However, these changes were not as obvious in the WT and S16D groups. Additionally, after OGD/R, Golgi Stress related protein contents were increased in the WT and S16D groups compared with the MOCK and S16A groups (P < 0.05). However, ER Stress related protein contents were decreased in the WT and S16D groups compared with the MOCK and S16A groups (P < 0.05). Our study demonstrates that Hsp20 phosphorylation on Ser16 protects against not only OGD/R-induced GA fragmentation in SH-SY5Y cells and N2a cells via Golgi stress but also OGD/R-induced ER structural changes in SH-SY5Y cells via ER stress. These findings suggest that Hsp20 is a potential drug target for ischemia stroke treatment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Endoplasmic Reticulum / metabolism
  • Endoplasmic Reticulum / physiology
  • Endoplasmic Reticulum Stress / physiology*
  • Glucose / metabolism*
  • Golgi Apparatus / metabolism*
  • Golgi Apparatus / physiology
  • HSP20 Heat-Shock Proteins / metabolism*
  • Humans
  • Mice
  • Mitochondria / metabolism
  • Mitochondria / physiology
  • Oxygen / metabolism*
  • Phosphorylation / physiology*
  • Reperfusion Injury / metabolism
  • Reperfusion Injury / physiopathology
  • Serine / metabolism*

Substances

  • HSP20 Heat-Shock Proteins
  • Serine
  • Glucose
  • Oxygen

Grants and funding

Zhipinghu, Grant no.81171239, National Natural Science Foundation of China, http://www.nsfc.gov.cn/; Liuwangzeng, Grant no.81202019, National Natural Science Foundation of China, http://www.nsfc.gov.cn/; Wenfanghe, Grant no. 81301121, http://www.nsfc.gov.cn/.