Protective activity of guanosine in an in vitro model of Parkinson's disease

Panminerva Med. 2012 Dec;54(1 Suppl 4):43-51.

Abstract

Parkinson's disease (PD) is a pathological condition characterized by a progressive neurodegeneration of dopaminergic neurons with the consequent reduction of dopamine content in the substantia nigra. The neurotoxin 6-hydroxydopamine (6-OHDA) is widely used to mimic the neuropathology of PD in both in vivo and in vitro experimental models. We found that, as expected, in dopaminergic human SH-SY5Y neuroblastoma cells the toxin reduced cell viability causing programmed cell death as assessed by an increase in DNA fragmentation. We also examined, in these cells, the activation/inactivation of several pro and anti apoptotic signaling pathways by 6-OHDA including p-38 kinase (p-38), c-Jun N-terminal kinase (JNK), protein kinase B (also known as Akt), glycogen synthase kinase-3β (GSK3β), and Bcl-2 protein. Guanine-based purines, exert neuroprotective effects and we previously reported that guanosine activates cell survival pathways including PI3K/Akt/PKB signaling in different kinds of cells including glia and neuroblastoma cells. In the present study we found that guanosine (300 µM) protected SH-SY5Y neuroblastoma cells when they were exposed to 6-OHDA, promoting their survival. Guanosine reduced the 6-OHDA mediated activation of p-38 and JNK. Moreover the nucleoside potentiated the early increase in the phosphorylation of the anti-apoptotic kinase Akt and the increase in the expression of the anti-apoptotic Bcl-2 protein induced by 6-OHDA. In summary our results show that guanosine results to be neuroprotective in a recognized in vitro model of PD thus suggesting that it could represent a new potential pharmacological tool to be studied in the therapeutic approach to PD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis
  • Cell Line, Tumor
  • Cell Proliferation
  • Cell Survival
  • Culture Media / pharmacology
  • DNA Fragmentation
  • Dose-Response Relationship, Drug
  • Guanosine / therapeutic use*
  • Humans
  • JNK Mitogen-Activated Protein Kinases / metabolism
  • Neuroprotective Agents / therapeutic use*
  • Oxidopamine / adverse effects
  • Parkinson Disease / drug therapy*
  • Phosphorylation
  • Signal Transduction
  • Substantia Nigra / drug effects*
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • Culture Media
  • Neuroprotective Agents
  • Guanosine
  • Oxidopamine
  • JNK Mitogen-Activated Protein Kinases
  • p38 Mitogen-Activated Protein Kinases