Cellular Physiology and Biochemistry (May 2018)

N-Cadherin Attenuates High Glucose-Induced Nucleus Pulposus Cell Senescence Through Regulation of the ROS/NF-κB Pathway

  • Gang Hou,
  • Huiqing Zhao,
  • Haijun Teng,
  • Pei Li,
  • Wenbin Xu,
  • Junbin Zhang,
  • Lulu Lv,
  • Zhiliang Guo,
  • Li Wei,
  • Hui Yao,
  • Yichun Xu

DOI
https://doi.org/10.1159/000489804
Journal volume & issue
Vol. 47, no. 1
pp. 257 – 265

Abstract

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Background/Aims: Diabetes mellitus (DM) is a potential etiology of disc degeneration. N-cadherin (N-CDH) helps maintain the cell viability, cell phenotype and matrix biosynthesis of nucleus pulposus (NP) cells. Here, we mainly aimed to investigate whether N-CDH can attenuate high glucose-induced NP cell senescence and its potential mechanism. Methods: Rat NP cells were cultured in a base culture medium and base culture medium with a 0.2 M glucose concentration. Recombinant lentiviral vectors were used to enhance N-CDH expression in NP cells. Senescence-associated β-galactosidase (SA-β-Gal) activity was measured by SA-β-Gal staining. NP cell proliferation was evaluated by CCK-8 assay. Telomerase activity and intracellular reactive oxygen species (ROS) content were tested by specific chemical kits according to the manufacturer’s instructions. G0/G1 cell cycle arrest was evaluated by flow cytometry. Real-time PCR and Western blotting were used to analyze mRNA and protein expressions of senescence markers (p16 and p53) and matrix macromolecules (aggrecan and collagen II). Additionally, p-NF-κB expression was also analyzed by Western blotting to evaluate NF-κB pathway activity. Results: High glucose significantly decreased N-CDH expression, increased ROS generation and NF-κB pathway activity, and promoted NP cell senescence, which was reflected in the increase in SA-β-Gal activity and senescence marker (p16 and p53) expression, compared to the control group. High glucose decreased telomerase activity and cell proliferation potency. However, N-CDH overexpression partially attenuated NP cell senescence, decreased ROS content and inhibited the activation of the NF-κB pathway under the high glucose condition. Conclusion: High glucose decreases N-CDH expression and promotes NP cell senescence. N-CDH overexpression can attenuate high glucose-induced NP cell senescence through the regulation of the ROS/ NF-κB pathway. This study suggests that N-CDH is a potential therapeutic target to slow DM-mediated disc NP degeneration.

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