Spinal cord injury as a trigger to develop periodic leg movements during sleep: An evolutionary perspective

Department of Neurology, School of Medicine, Universidade de São Paulo, São Paulo, SP, Brazil.
Arquivos de neuro-psiquiatria (Impact Factor: 0.84). 11/2012; 70(11):880-4. DOI: 10.1590/S0004-282X2012001100011
Source: PubMed


The primary trigger to periodic limb movement (PLM) during sleep is still unknown. Its association with the restless legs syndrome (RLS) is established in humans and was reported in spinal cord injury (SCI) patients classified by the American Spinal Injury Association (ASIA) as A. Its pathogenesis has not been completely unraveled, though recent advances might enhance our knowledge about those malfunctions. PLM association with central pattern generator (CPG) is one of the possible pathologic mechanisms involved. This article reviewed the advances in PLM and RLS genetics, the evolution of CPG functioning, and the neurotransmitters involved in CPG, PLM and RLS. We have proposed that SCI might be a trigger to develop PLM.


Available from: Susana Cristina Lerosa Telles, Aug 06, 2014
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    • "Despite the great effort to understand the inhibitory nature of neuronal environment to regenerating fibers, recent results have pointed out neuronal plasticity in the lesioned spinal cord as the major event leading functional recovery in that pathological condition [6] [7] [8] [9] [10]. In fact, studies have identified and characterized molecular signals related to axonal growth and functional target innervation in the lesioned spinal cord. "
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    ABSTRACT: Pigment epithelium derived factor (PEDF) exerts trophic actions to motoneurons and modulates nonneuronal restorative events, but its effects on neuroplasticity responses after spinal cord (SC) injury are unknown. Rats received a low thoracic SC photothrombotic ischemia and local injection of PEDF and were evaluated behaviorally six weeks later. PEDF actions were detailed in SC ventral horn (motor) in the levels of the lumbar central pattern generator (CPG), far from the injury site. Molecules related to neuroplasticity (MAP-2), those that are able to modulate such event, for instance, neurotrophic factors (NT-3, GDNF, BDNF, and FGF-2), chondroitin sulfate proteoglycans (CSPG), and those associated with angiogenesis and antiapoptosis (laminin and Bcl-2) and Eph (receptor)/ephrin system were evaluated at cellular or molecular levels. PEDF injection improved motor behavioral performance and increased MAP-2 levels and dendritic processes in the region of lumbar CPG. Treatment also elevated GDNF and decreased NT-3, laminin, and CSPG. Injury elevated EphA4 and ephrin-B1 levels, and PEDF treatment increased ephrin A2 and ephrins B1, B2, and B3. Eph receptors and ephrins were found in specific populations of neurons and astrocytes. PEDF treatment to SC injury triggered neuroplasticity in lumbar CPG and regulation of neurotrophic factors, extracellular matrix molecules, and ephrins.
    Neural Plasticity 07/2014; 2014(21):451639. DOI:10.1155/2014/451639 · 3.60 Impact Factor
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    ABSTRACT: In this study we examine the temporal connection between periodic leg movements (PLMs) and cortical arousals, as well as the treatment effect of pramipexole, in a clinical case with spinal cord lesion. A patient with complete cervical spinal cord injury and PLMs during sleep underwent two baseline sleep recordings, one recording with dopaminergic treatment, and one recording with adaptive servoventilation. The PLMs were temporally dissociated from cortical arousals as well as from respiratory or heart rate events. PLMs were suppressed by pramipexole and persisted after treatment of apnea. The disconnection of PLMs from arousals supports a spinal generator or peripheral trigger mechanism for PLMs. The suppression of movements by a dopamine agonist suggests that its site of action is caudal to the cervical lesion and outside of the brain. Our observation provides significant new knowledge about the pathogenesis of PLMs and warrants studies in larger populations. Salminen AV; Manconi M; Rimpilä V; Luoto TM; Koskinen E; Ferri R; Öhman J; Polo O. Disconnection between periodic leg movements and cortical arousals in spinal cord injury. J Clin Sleep Med 2013;9(11):1207-1209.
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