Biomedicines (Jul 2021)

Vagus Nerve Stimulation with Mild Stimulation Intensity Exerts Anti-Inflammatory and Neuroprotective Effects in Parkinson’s Disease Model Rats

  • Ittetsu Kin,
  • Tatsuya Sasaki,
  • Takao Yasuhara,
  • Masahiro Kameda,
  • Takashi Agari,
  • Mihoko Okazaki,
  • Kakeru Hosomoto,
  • Yosuke Okazaki,
  • Satoru Yabuno,
  • Satoshi Kawauchi,
  • Ken Kuwahara,
  • Jun Morimoto,
  • Kyohei Kin,
  • Michiari Umakoshi,
  • Yousuke Tomita,
  • Naoki Tajiri,
  • Cesario V. Borlongan,
  • Isao Date

DOI
https://doi.org/10.3390/biomedicines9070789
Journal volume & issue
Vol. 9, no. 7
p. 789

Abstract

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Background: The major surgical treatment for Parkinson’s disease (PD) is deep brain stimulation (DBS), but a less invasive treatment is desired. Vagus nerve stimulation (VNS) is a relatively safe treatment without cerebral invasiveness. In this study, we developed a wireless controllable electrical stimulator to examine the efficacy of VNS on PD model rats. Methods: Adult female Sprague-Dawley rats underwent placement of a cuff-type electrode and stimulator on the vagus nerve. Following which, 6-hydroxydopamine (6-OHDA) was administered into the left striatum to prepare a PD model. VNS was started immediately after 6-OHDA administration and continued for 14 days. We evaluated the therapeutic effects of VNS with behavioral and immunohistochemical outcome assays under different stimulation intensity (0.1, 0.25, 0.5 and 1 mA). Results: VNS with 0.25–0.5 mA intensity remarkably improved behavioral impairment, preserved dopamine neurons, reduced inflammatory glial cells, and increased noradrenergic neurons. On the other hand, VNS with 0.1 mA and 1 mA intensity did not display significant therapeutic efficacy. Conclusions: VNS with 0.25–0.5 mA intensity has anti-inflammatory and neuroprotective effects on PD model rats induced by 6-OHDA administration. In addition, we were able to confirm the practicality and effectiveness of the new experimental device.

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