Early Presymptomatic and Long-Term Changes of Rest Activity Cycles and Cognitive Behavior in a MPTP-Monkey Model of Parkinson's Disease
2011

Changes in Rest Activity Cycles and Cognitive Behavior in MPTP-Monkeys with Parkinson's Disease

Sample size: 4 publication 10 minutes Evidence: moderate

Author Information

Author(s): Vezoli Julien, Fifel Karim, Leviel Vincent, Dehay Colette, Kennedy Henry, Cooper Howard M., Gronfier Claude, Procyk Emmanuel

Primary Institution: Inserm, U846, Stem Cell and Brain Research Institute, Bron, France

Hypothesis

How do rest-activity rhythms and cognitive behavior change in monkeys treated with MPTP, a neurotoxin that induces Parkinson's disease symptoms?

Conclusion

MPTP treatment leads to early detectable changes in rest-activity cycles and cognitive deficits, which persist long after motor symptoms have recovered.

Supporting Evidence

  • MPTP treatment led to immediate alterations in rest-activity cycles and cognitive deficits.
  • Motor deficits appeared 3 to 5 weeks after starting MPTP treatment.
  • Clinical scores returned to control levels 5–7 weeks after stopping MPTP treatment in three monkeys.
  • Cognitive deficits persisted for many months after motor recovery.

Takeaway

The study shows that monkeys treated with a toxin for Parkinson's disease show changes in their daily activity and thinking skills before they show any movement problems.

Methodology

Monkeys were treated with low doses of MPTP, and their behavior was monitored continuously for up to 16 months, assessing cognitive performance and rest-activity cycles.

Potential Biases

Potential bias in the interpretation of behavioral changes due to the subjective nature of cognitive assessments.

Limitations

The study involved a small sample size of only four monkeys, which may limit the generalizability of the findings.

Participant Demographics

Four monkeys: three female Macaca fascicularis and one male Macaca mulatta, aged 11 to 15 years.

Statistical Information

P-Value

p<0.05

Statistical Significance

p<0.05

Digital Object Identifier (DOI)

10.1371/journal.pone.0023952

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