Pharmacotherapy in restorative neurology

Endogenous defense mechanism-based neuroprotection in large-vessel acute ischemic stroke: A hope for future

BACKGROUND

Stroke is a leading cause of morbidity and mortality worldwide and a leading cause of disability. None of the neuroprotective agents have been approved internationally except edaravone in Japanese guidelines in acute ischemic stroke. We here discuss that there are two types of endogenous defense mechanisms (EDMs) after acute stroke for neuromodulation and neuroregeneration, and if both can be activated simultaneously, then we can have better recovery in stroke.

AIMS AND OBJECTIVES

We aimed to study the effect of combination of neuroprotection therapies acting on the two wings of EDM in acute large-vessel middle cerebral artery (LMCA) ischemic stroke.

METHODS

Sixty patients of LMCA stroke were enrolled and randomized within 72 h into two groups of 30 patients each. The control group received standard medical care without any neuroprotective agents while the intervention group received standard medical care combined with oral citicoline with vinpocetine for 3 months with initial 1 week intravenous and edaravone and cerebrolysin injection, started within 72 h of onset of stroke. Patients were assessed on the basis of the National Institutes of Health Stroke Scale, Fugl-Meyer Assessment Score, Glasgow Coma Scale, and Mini-Mental Status Examination at admission, discharge, and after 90 days.

RESULTS

The intervention group showed significant and early improvements in motor as well as cognitive recovery.

CONCLUSION

Combination therapy for neuroprotection which is acting on two pathways of EDM can be useful in functional recovery after acute ischemic stroke.

Safety and Efficacy of SSRIs in Improving Poststroke Recovery: A Systematic Review and Meta-Analysis

Background Several studies investigated the role of selective serotonin reuptake inhibitors (SSRIs) in improving poststroke recovery; thus, we have decided to conduct this systematic review and meta-analysis to investigate the efficacy and safety of SSRIs in poststroke recovery. Methods and Results In this meta-analysis we searched the following databases: PubMed, Cochrane, Scopus, and Google Scholar. The studies were included if they were placebo-controlled trials in design and reported SSRIs' effects on poststroke depression, anxiety, disability, dependence, motor abilities, and cognitive functions. The quality of the included studies was assessed using the revised Cochrane risk-of-bias tool for randomized trials. The search yielded 44 articles that included 16 164 patients, and about half of the participants were treated with SSRIs. Our results showed that SSRIs had a significant effect on preventing depression (weighted mean difference [WMD], -7.05 [95% CI, -11.78 to -2.31]), treating depression according to the Hamilton Rating Scale for Depression score (WMD, -1.45 [95% CI, -2.77 to -0.14]), anxiety (relative risk, 0.23 [95% CI, 0.09-0.61]), dependence (WMD, 8.86 [95% CI, 1.23-16.48]), motor abilities according to National Institutes of Health Stroke Scale score (WMD, -0.79 [95% CI, -1.42 to -0.15]), and cognitive functions (WMD, 1.00 [95% CI, 0.12-1.89]). On the other hand, no significant effect of SSRIs on disability was observed. Additionally, we found that treating with SSRIs increased the risk of seizures (relative risk, 1.44 [95% CI, 1.13-1.83]), whereas there was no difference in the incidence of gastrointestinal symptoms or bleeding between SSRIs and a placebo. Conclusions Our study showed that SSRIs are effective in preventing and treating depression, and improving anxiety, motor function, cognitive function, and dependence in patients after stroke. These benefits were only reproducible with the citalopram subanalysis but not fluoxetine. Further well-conducted placebo-controlled trials are needed to investigate the safety and efficacy of citalopram among patients after stroke. Registration URL: www.crd.york.ac.uk/prospero/; Unique identifier: CRD42021285766.

Role of the Dopaminergic System in the Striatum and Its Association With Functional Recovery or Rehabilitation After Brain Injury

Disabilities are estimated to occur in approximately 2% of survivors of traumatic brain injury (TBI) worldwide, and disability may persist even decades after brain injury. Facilitation or modulation of functional recovery is an important goal of rehabilitation in all patients who survive severe TBI. However, this recovery tends to vary among patients because it is affected by the biological and physical characteristics of the patients; the types, doses, and application regimens of the drugs used; and clinical indications. In clinical practice, diverse dopaminergic drugs with various dosing and application procedures are used for TBI. Previous studies have shown that dopamine (DA) neurotransmission is disrupted following moderate to severe TBI and have reported beneficial effects of drugs that affect the dopaminergic system. However, the mechanisms of action of dopaminergic drugs have not been completely clarified, partly because dopaminergic receptor activation can lead to restoration of the pathway of the corticobasal ganglia after injury in brain structures with high densities of these receptors. This review aims to provide an overview of the functionality of the dopaminergic system in the striatum and its roles in functional recovery or rehabilitation after TBI.

Effect of Qizhitongluo capsule on lower limb rehabilitation after stroke: A randomized clinical trial

BACKGROUND

An individual's level of lower limb motor function is associated with his or her disability level after stroke, and motor improvement may lead to a better prognosis and quality of life. Data from animal models show that Qizhitongluo (QZTL) capsule facilitates recovery after focal brain injury. We aimed to validate the efficacy and safety of the QZTL capsule for promoting lower limb motor recovery in poststroke patients.

METHODS

In this randomized, multicenter, double-blind, placebo- and active-controlled trial from 13 sites in China, participants with ischemic stroke and Fugl-Meyer motor scale (FMMS) scores of <95 were eligible for inclusion. Patients were randomly assigned in a 2:1:1 ratio to the QZTL group, Naoxintong (NXT) group or placebo group for 12 weeks at 15-28 days after the onset of stroke. The primary outcome was the change in the Lower Limb FMMS (FMMS-LL) score from baseline over the 12-week intervention period.

RESULTS

622 participants were randomly assigned to the QZTL group (309), NXT group (159), or placebo group (154). The FMMS-LL score increased by 4.81 points (95 % CI, 4.27-5.35) in the QZTL group, by 3.77 points (95 % CI, 3.03-4.51) in the NXT group and by 3.00 points (95 % CI, 3.03-4.51) in the placebo group at week 12. The QZTL group showed significantly larger improvements compared with the placebo group at each interview from weeks 4-12 (difference, 0.89 [0.30,1.49] at week 4, P = 0.0032; difference, 1.83[1.01,2.66] at 90 days poststroke, P < 0.0001; difference, 1.81[0.88,2.74] at week 12, P = 0.0001).

CONCLUSION

The QZTL capsule is an effective treatment for lower limb motor impairment. The finding indicates that the QZTL capsule may be used as a potential new strategy for stroke rehabilitation.

Serotonin Selective Reuptake Inhibitors (SSRIs) and Stroke

PURPOSE OF REVIEW

The interest in SSRIs after stroke has increased in the past few years, with better knowledge of post-stroke depression and with the demonstrated capacity of some SSRIs to act on the functional recovery of non-depressed subjects.

RECENT FINDINGS

Arguments for the action of SSRIs in favour of post-stroke neurological function recovery have improved through new elements: basic science and preclinical data, positive clinical trials and repeated series of stroke patient meta-analysis, and confirmation of favourable safety conditions in post-stroke patients. Global coherence is appearing, showing that SSRIs improve stroke recovery in non-depressed patients when given for 3 months after the stroke, with highly favourable safety conditions and a favourable benefit/risk ratio. Large series are still needed.

The effect of donepezil on the cognitive ability early in the course of recovery from traumatic brain injury

OBJECTIVE

To investigate the effect of donepezil on cognitive ability in patients who have sustained a traumatic brain injury (TBI). We hypothesized that donepezil, an acetylcholinesterase inhibitor, would enhance cognitive recovery beyond that of usual care in an acute rehabilitation facility.

METHODS

This retrospective, longitudinal analysis included 55 patients who were non-randomly prescribed donepezil during acute care and compared them to 74 patients who received usual rehabilitation treatment. All 129 patients completed neuropsychological assessment at two time points. Donepezil was increased from 5 to 10 mg 7-10 days after initiation and maintained until follow-up cognitive assessment.

MAIN OUTCOMES

Primary cognitive abilities of interest included processing speed, attention and memory. Cognitive and functional abilities were assessed by a standard neuropsychological battery for TBI.

RESULTS

Propensity scores were used to adjust for differences between groups. Mixed effect model analysis showed no significant differences between treatment and control groups on all neuropsychological subtests over time.

CONCLUSIONS

Acute administration of donepezil did not significantly improve measures of cognitive or functional ability beyond that of treatment as usual in patients with moderate-to-severe TBI.

Update on pharmacotherapy for stroke and traumatic brain injury recovery during rehabilitation

PURPOSE OF REVIEW

This article evaluates whether specific drugs are able to facilitate motor recovery after stroke or improve the level of consciousness, cognitive, or behavioral symptoms after traumatic brain injury.

RECENT FINDINGS

After stroke, serotonin reuptake inhibitors can enhance restitution of motor functions in depressed as well as in nondepressed patients. Erythropoietin and progesterone administered within hours after moderate to severe traumatic brain injury failed to improve the outcome. A single dose of zolpidem can transiently improve the level of consciousness in patients with vegetative state or minimally conscious state.

SUMMARY

Because of the lack of large randomized controlled trials, evidence is still limited. Currently, most convincing evidence exists for fluoxetine for facilitation of motor recovery early after stroke and for amantadine for acceleration of functional recovery after severe traumatic brain injury. Methylphenidate and acetylcholinesterase inhibitors might enhance cognitive functions after traumatic brain injury. Sufficiently powered studies and the identification of predictors of beneficial drug effects are still needed.

[Ethical aspects of teaching of nervous diseases]

Ethical aspects of training of physicians are considered. The author highlights the importance of teaching the basic disciplines during the training of the neurologist. An analysis of most frequent mistakes that arise in practical activity as a consequence of overestimation of paraclinical methods of investigation, underestimation of a role of treatment that the patient receives due to other indications is presented. The formation of life attitude of the physician is the extremely important component of teaching process. One should not forget the lessons of history shown examples of physicians that gave their lives to save patients. Also, there are examples of physicians who had violated the fundamental humanitarian principles.

Buyang Huanwu decoction facilitates neurorehabilitation through an improvement of synaptic plasticity in cerebral ischemic rats

BACKGROUND

Loss of neural function is a critical but unsolved issue after cerebral ischemia insult. Neuronal plasticity and remodeling are crucial for recovery of neural functions after brain injury. Buyang Huanwu decoction, which is a classic formula in traditional Chinese medicine, can positively alter synaptic plasticity. This study assessed the effects of Buyang Huanwu decoction in combination with physical exercise on neuronal plasticity in cerebral ischemic rats.

METHODS

Cerebral ischemic rats were administered Buyang Huanwu decoction and participated in physical exercise after the induction of a permanent middle cerebral artery occlusion. The neurobehavioral functions and infarct volumes were evaluated. The presynaptic (SYN), postsynaptic (GAP-43) and cytoskeletal (MAP-2) proteins in the coronal brain samples were evaluated by immunohistochemistry and western blot analyses. The ultrastructure of the neuronal synaptic junctions in the same region were analyzed using transmission electron microscopy.

RESULTS

Combination treatment of Buyang Huanwu decoction and physical exercise ameliorated the neurobehavioral deficits (p < 0.05), significantly enhanced the expression levels of SYN, GAP-43 and MAP-2 (p < 0.05), and maintained the synaptic ultrastructure.

CONCLUSIONS

Buyang Huanwu decoction facilitated neurorehabilitation following a cerebral ischemia insult through an improvement in synaptic plasticity. Graphical abstract The Buyang Huanwu decoction (BYHWD) combined with physical exercise (PE) attenuates synaptic disruption and promotes synaptic plasticity following cerebral ischemia (stroke).

Fluoxetine induces vascular endothelial growth factor/Netrin over-expression via the mediation of hypoxia-inducible factor 1-alpha in SH-SY5Y cells

Fluoxetine has become one of the most promising drugs for improving clinical outcome in patients with cerebral infarction. Although the clinical efficacy of fluoxetine has been preliminarily demonstrated, its mechanism remains unclear. Hypoxia-inducible factor 1-alpha (HIF-1α) is upstream to Netrin and vascular endothelial growth factor (VEGF), and under hypoxia conditions it may induce expression of Netrin-1 and VEGF in vascular endothelial cells. We sought to explore whether it can regulate their expression in hypoxia and mediate the effect of fluoxetine in hypoxia. In this study, the effect of hypoxia on the expression of VEGF and Netrin was observed in vitro by real-time PCR and western blotting in SH-SY5Y cells; the binding sites of HIF-1α in VEGF and Netrin gene promoters were identified by luciferase reporter; the effect of fluoxetine on binding of HIF-1α with Netrin and VEGF promoters in hypoxia was observed by Chromatin Immunoprecipitation (ChIP) Assay. We prove that HIF-1α regulates transcription of both VEGF and Netrin, and that in hypoxia fluoxetine up-regulates VEGF and Netrin expression via mediation of HIF-1α that binds to hypoxia-response element sites of VEGF and Netrin promoters. Our study indicates that HIF-1α may play an important role in the treatment of cerebral infarction through mediating the recovery of neurological function induced by fluoxetine, which provides theoretical basis for the development of gene therapeutic drugs targeting HIF-1α. We show that hypoxia-inducible factor 1-alpha (HIF-1α) regulates transcription of both vascular endothelial growth factor (VEGF) and Netrin. Furthermore, we also show that in hypoxia fluoxetine up-regulates VEGF and Netrin expression via mediation of HIF-1α that binds to hypoxia-response element (HRE) sites of VEGF and Netrin promoters. Our study indicates that HIF-1α may play an important role in the treatment of cerebral infarction through mediating the recovery of neurological function induced by fluoxetine. These findings provide a theoretical basis for development of gene therapeutic drugs targeting HIF-1α.

Drugs for behavior disorders after traumatic brain injury: Systematic review and expert consensus leading to French recommendations for good practice

OBJECTIVE

There are no handbook or recommendations for the use of pharmacological agents to treat neurobehavioral disorders after traumatic brain injury (TBI). This work proposes a systematic review of the literature and a user guide on neuroleptics, antidepressants, beta-blockers, mood stabilizers and other medications for irritability, aggressiveness, agitation, impulsivity, depression, apathy…

METHOD

Steering, working and reading groups (62 people) were formed under the control of the French High Authority for Health (HAS) in collaboration with the SOFMER scientific society (French Society of Physical and Rehabilitation Medicine). Articles were searched by HAS officers in the Medline database from 1990 to 2012, crossing TBI and pharmacological agents. The HAS method to select, read and analyze papers is close to the PRISMA statements.

RESULTS

Out of 772 references, 89 were analyzed, covering a total of 1306 people with TBI. There is insufficient evidence to standardize drug treatments for these disorders. There are however some elements to establish consensus recommendations for good clinical practice. Propranolol can improve aggression (B grade). Carbamazepine and valproate seem effective on agitation and aggression and are recommended as first line treatment (Expert Consensus [EC]). There is no evidence of efficacy for neuroleptics. Their prescription is based on emergency situation for a crisis (loxapine) but not for long-term use (EC). Antidepressants are recommended to treat depression (EC) with a higher standard of proof for Selective Serotonin Reuptake Inhibitors (SSRI, grade B). Other products are described.

CONCLUSION

The choice of treatment depends on the level of evidence, target symptoms, custom objectives, clinical experience and caution strategies.

Care management of the agitation or aggressiveness crisis in patients with TBI. Systematic review of the literature and practice recommendations

The agitation crisis in the awakening phase after traumatic brain injury (TBI) is one of the most difficult behavioral disorders to alleviate. Current treatment options are heterogeneous and may involve excessive sedation. Practice guidelines are required by professionals in charge of TBI patients. Few reviews were published but those are old and based on expert opinions. The purpose of this work is to propose evidence-based guidelines to treat the agitation crisis.

METHODS

The elaboration of these guidelines followed the procedure validated by the French health authority for good practice recommendations, close to the Prisma statement. Guidelines were elaborated on the basis of a systematic and critical review of the literature.

RESULTS

Twenty-eight articles concerning 376 patients were analyzed. Recommendations are: when faced with an agitation crisis, the management strategy implies to search for an underlying factor that should be treated such as pain, acute sepsis, and drug adverse effect (expert opinion). Physical restraints should be discarded when possible (expert opinion). Neuroleptic agent with a marketing authorization can be used in order to obtain a quick sedation so as to protect the patient from himself, closed ones or the healthcare team but the duration should be as short as possible (expert opinion). The efficacy of beta-blockers and antiepileptics with mood regulation effects like carbamazepine and valproate yield the most compelling evidence and should be preferably used when a background regimen is envisioned (grade B for beta-blocker and C for antiepileptics). Neuroleptics, antidepressants, benzodiazepines, buspirone may be prescribed but are considered second-line treatments (expert opinion).

CONCLUSION

This study provides a strategy for treating the agitation crisis based on scientific data and expert opinion. The level of evidence remains low and published data are often old. New studies are essential to validate results from previous studies and test new drugs and non-pharmaceutical therapies.

Pharmacotherapy of traumatic brain injury: state of the science and the road forward: report of the Department of Defense Neurotrauma Pharmacology Workgroup

Despite substantial investments by government, philanthropic, and commercial sources over the past several decades, traumatic brain injury (TBI) remains an unmet medical need and a major source of disability and mortality in both developed and developing societies. The U.S. Department of Defense neurotrauma research portfolio contains more than 500 research projects funded at more than $700 million and is aimed at developing interventions that mitigate the effects of trauma to the nervous system and lead to improved quality of life outcomes. A key area of this portfolio focuses on the need for effective pharmacological approaches for treating patients with TBI and its associated symptoms. The Neurotrauma Pharmacology Workgroup was established by the U.S. Army Medical Research and Materiel Command (USAMRMC) with the overarching goal of providing a strategic research plan for developing pharmacological treatments that improve clinical outcomes after TBI. To inform this plan, the Workgroup (a) assessed the current state of the science and ongoing research and (b) identified research gaps to inform future development of research priorities for the neurotrauma research portfolio. The Workgroup identified the six most critical research priority areas in the field of pharmacological treatment for persons with TBI. The priority areas represent parallel efforts needed to advance clinical care; each requires independent effort and sufficient investment. These priority areas will help the USAMRMC and other funding agencies strategically guide their research portfolios to ensure the development of effective pharmacological approaches for treating patients with TBI.

Vagus nerve stimulation in ischemic stroke: old wine in a new bottle

Vagus nerve stimulation (VNS) is currently Food and Drug Administration-approved for treatment of both medically refractory partial-onset seizures and severe, recurrent refractory depression, which has failed to respond to medical interventions. Because of its ability to regulate mechanisms well-studied in neuroscience, such as norepinephrine and serotonin release, the vagus nerve may play an important role in regulating cerebral blood flow, edema, inflammation, glutamate excitotoxicity, and neurotrophic processes. There is strong evidence that these same processes are important in stroke pathophysiology. We reviewed the literature for the role of VNS in improving ischemic stroke outcomes by performing a systematic search for publications in Medline (1966–2014) with keywords “VNS AND stroke” in subject headings and key words with no language restrictions. Of the 73 publications retrieved, we identified 7 studies from 3 different research groups that met our final inclusion criteria of research studies addressing the role of VNS in ischemic stroke. Results from these studies suggest that VNS has promising efficacy in reducing stroke volume and attenuating neurological deficits in ischemic stroke models. Given the lack of success in Phase III trials for stroke neuroprotection, it is important to develop new therapies targeting different neuroprotective pathways. Further studies of the possible role of VNS, through normally physiologically active mechanisms, in ischemic stroke therapeutics should be conducted in both animal models and clinical studies. In addition, recent advent of a non-invasive, transcutaneous VNS could provide the potential for easier clinical translation.

Pharmacological therapies in post stroke recovery: recommendations for future clinical trials

Stroke is a leading cause of serious long-term disability in adults and is the second leading cause of death worldwide. Early reperfusion and neuroprotection techniques have been the focus of much effort with the aim of very acute treatment of the stroke. Targeting different mechanisms, pharmacological therapies have the potential to reduce disability in a large fraction of patients who survive the acute stroke. The brain's capacity to reorganize after stroke through plasticity mechanisms can be modulated by pharmacological agents. A number of therapeutic interventions are under study, including small molecules, growth factors, and monoclonal antibodies. Recently it has been shown that the SSRI fluoxetine improved motor deficit in patients with ischaemic stroke and hemiplegia which appeared to be independent of the presence of depression. In this context, it is of major importance to support innovative research in order to promote the emergence of new pharmacological treatments targeting neurological recovery after stroke, as opposed to acute de-occlusion and neuroprotection. This paper is the work of a group of 14 scientists with aim of (1) addressing key areas of the basic and clinical aspects of human brain plasticity after stroke and potential pharmacological targets for recovery, (2) asking questions about the most appropriate characteristics of clinical trials testing drugs in post stroke recovery and (3) proposing recommendations for future clinical trials.

Pharmacologic approaches to cerebral aging and neuroplasticity: insights from the stroke model

Brain plasticity is an intrinsic characteristic of the nervous system that allows continuous remodeling of brain functions in pathophysiological conditions. Although normal aging is associated with morphological modifications and decline of cerebral functions, brain plasticity is at least partially preserved in elderly individuals. A growing body of evidence supports the notion that cognitive enrichment and aerobic training induce a dynamic reorganization of higher cerebral functions, thereby helping to maintain operational skills in the elderly and reducing the incidence of dementia. The stroke model clearly shows that spontaneous brain plasticity exists after a lesion, even in old patients, and that it can be modulated through external factors like rehabilitation and drugs. Whether drugs can be used with the aim of modulating the effects of physical training or cognitive stimulation in healthy aged people has not been addressed until now. The risk:benefit ratio will be the key question with regard to the ethical aspect of this challenge. We review in this article the main aspects of human brain plasticity as shown in patients with stroke, the drug modulation of brain plasticity and its consequences on recovery, and finally we address the question of the influence of aging on brain plasticity.

Management of patients with stroke: is it time to expand treatment options?

Approximately 700,000 people in the United States have an ischemic stroke annually. Substantial research has tested therapies for the very early treatment of ischemic stroke but, to date, only intravenous thrombolysis and intra-arterial measures to restore perfusion have shown success. Despite a 15-year effort to increase the use of these therapies, only approximately 5% of patients with stroke are currently being treated. Although most patients with stroke have some neurological recovery, more than half of stroke survivors have residual impairments that lead to disability or long-term institutionalized care. Laboratory research has demonstrated several mechanisms that help the brain to recover after a stroke. New pharmacological and cell-based approaches that are known to promote brain plasticity are emerging from laboratory studies and may soon expand the window for stroke treatment to restore function. It is time to build on this knowledge and to translate the understanding of recovery after stroke into the clinical setting. Measures that might augment recovery should become a major focus of clinical research in stroke in the 21st century.

Use of antidepressant medications to improve outcomes after stroke

Interest in the use of antidepressants after stroke has been renewed by better knowledge of poststroke depression, but mainly by the capacity of some of them to promote functional recovery of nondepressed subjects. Recombinant tissue plasminogen activator thrombolysis within the first few hours after the stroke is currently the only validated treatment able to improve the spontaneous--and most of the time incomplete--recovery of neurological functions after stroke. However, we have learned from research over the last decade, in part based on the considerable improvement of neuroimaging techniques, that spontaneous recovery of neurological functions is associated with a large intracerebral reorganization of the damaged human brain. The question of whether lesioned-brain plasticity can be modulated by external factors such as pharmacological antidepressant agents is now being addressed with the aim of improving recovery and reducing the final disability of patients. Poststroke depression is known to be frequent and deleterious for patient outcome. We review the interest in the use of antidepressants after stroke in classic but often neglected poststroke depression and we strongly underline the action of some antidepressants in promoting functional recovery of nondepressed patients after stroke.

Genetic variation in the human brain dopamine system influences motor learning and its modulation by L-Dopa

Dopamine is important to learning and plasticity. Dopaminergic drugs are the focus of many therapies targeting the motor system, where high inter-individual differences in response are common. The current study examined the hypothesis that genetic variation in the dopamine system is associated with significant differences in motor learning, brain plasticity, and the effects of the dopamine precursor L-Dopa. Skilled motor learning and motor cortex plasticity were assessed using a randomized, double-blind, placebo-controlled, crossover design in 50 healthy adults during two study weeks, one with placebo and one with L-Dopa. The influence of five polymorphisms with established effects on dopamine neurotransmission was summed using a gene score, with higher scores corresponding to higher dopaminergic neurotransmission. Secondary hypotheses examined each polymorphism individually. While training on placebo, higher gene scores were associated with greater motor learning (p = .03). The effect of L-Dopa on learning varied with the gene score (gene score*drug interaction, p = .008): participants with lower gene scores, and thus lower endogenous dopaminergic neurotransmission, showed the largest learning improvement with L-Dopa relative to placebo (p<.0001), while L-Dopa had a detrimental effect in participants with higher gene scores (p = .01). Motor cortex plasticity, assessed via transcranial magnetic stimulation (TMS), also showed a gene score*drug interaction (p = .02). Individually, DRD2/ANKK1 genotype was significantly associated with motor learning (p = .02) and its modulation by L-Dopa (p<.0001), but not with any TMS measures. However, none of the individual polymorphisms explained the full constellation of findings associated with the gene score. These results suggest that genetic variation in the dopamine system influences learning and its modulation by L-Dopa. A polygene score explains differences in L-Dopa effects on learning and plasticity most robustly, thus identifying distinct biological phenotypes with respect to L-Dopa effects on learning and plasticity. These findings may have clinical applications in post-stroke rehabilitation or the treatment of Parkinson's disease.

Midbrain raphe stimulation improves behavioral and anatomical recovery from fluid-percussion brain injury

The midbrain median raphe (MR) and dorsal raphe (DR) nuclei were tested for their capacity to regulate recovery from traumatic brain injury (TBI). An implanted, wireless self-powered stimulator delivered intermittent 8-Hz pulse trains for 7 days to the rat's MR or DR, beginning 4-6 h after a moderate parasagittal (right) fluid-percussion injury. MR stimulation was also examined with a higher frequency (24 Hz) or a delayed start (7 days after injury). Controls had sham injuries, inactive stimulators, or both. The stimulation caused no apparent acute responses or adverse long-term changes. In water-maze trials conducted 5 weeks post-injury, early 8-Hz MR and DR stimulation restored the rate of acquisition of reference memory for a hidden platform of fixed location. Short-term spatial working memory, for a variably located hidden platform, was restored only by early 8-Hz MR stimulation. All stimulation protocols reversed injury-induced asymmetry of spontaneous forelimb reaching movements tested 6 weeks post-injury. Post-mortem histological measurement at 8 weeks post-injury revealed volume losses in parietal-occipital cortex and decussating white matter (corpus callosum plus external capsule), but not hippocampus. The cortical losses were significantly reversed by early 8-Hz MR and DR stimulation, the white matter losses by all forms of MR stimulation. The generally most effective protocol, 8-Hz MR stimulation, was tested 3 days post-injury for its acute effect on forebrain cyclic adenosine monophosphate (cAMP), a key trophic signaling molecule. This procedure reversed injury-induced declines of cAMP levels in both cortex and hippocampus. In conclusion, midbrain raphe nuclei can enduringly enhance recovery from early disseminated TBI, possibly in part through increased signaling by cAMP in efferent targets. A neurosurgical treatment for TBI using interim electrical stimulation in raphe repair centers is suggested.

Emerging therapies in neurorehabilitation

Just as advancing technology has furthered our understanding of how the nervous system recovers, technology also enables the development of novel approaches to treatment. Because nervous system disease and injury often lead to severely impaired function, patients and families are willing to try anything, so therapies are often adopted with little evidence that they actually work. Evidence shows that comprehensive rehabilitation programs produce better outcomes, but it is still not understood what components of these multifaceted programs are critical to their success. Functional neuroimaging and other modalities now allow monitoring of neurophysiologic changes that can be paired with assessments detailing clinical changes, furthering our understanding of the factors that influence the recovery process. This article discusses several novel and emerging therapies in neurorehabilitation as well as recent multistudy reviews of selected treatments.

Traumatic brain injury: special problem, special care

External physical insult, an accidental blow, acceleration followed by rapid deceleration, or explosive blasts can cause traumatic brain injury (TBI). During the last few years, experts have realized that even mild blows to the head can cause lasting damage. Better understanding of how TBI occurs has improved the probability of survival for those with the most serious injuries. Graded using the Glasgow Coma Scale, TBI may leave its sufferers awake, in periods of alertness interspersed with cognitive confusion, or deep in coma. Falls recently displaced motor vehicle accidents as the leading cause of TBI. Elders are at high risk for falls and TBI, and they may be unaware of possible lasting complications. Pharmacologic therapies for patients who have suffered TBI are, by necessity, individualized.

Dose-dependent nonlinear effect of L-DOPA on paired associative stimulation-induced neuroplasticity in humans

Dopamine is one of the major neuromodulators in the CNS, which is involved in learning and memory processes. A nonlinear, inverted U-shaped dose-response curve of its effects on cognition has been observed in animal studies. The basis for this nonlinear effect might be a similar effect of dopamine on neuroplasticity. Whereas it has been shown that dopamine affects paired associative stimulation (PAS)-induced plasticity, which might reflect learning-related processes to a larger degree than other noninvasive plasticity induction protocols in the human motor cortex in principle, its dose-dependency has not been explored previously. We studied the effect of different dosages of the dopamine precursor L-DOPA on motor cortex plasticity induced by facilitatory and inhibitory PAS of the motor cortex in 12 healthy humans. They received 25, 100, or 200 mg of L-DOPA or placebo medication combined with either excitability-enhancing or -diminishing PAS. Cortical excitability level was monitored before and for up to 2 d after plasticity induction by assessment of transcranial magnetic stimulation-induced motor-evoked potentials. Low-dose L-DOPA abolished the aftereffects of PAS and medium-dose L-DOPA prolonged facilitatory plasticity. High-dose L-DOPA reversed the excitability enhancement accomplished by facilitatory PAS to diminution. Thus, the results show a clear nonlinear effect of L-DOPA dosage on associative plasticity, different from that on nonfocal plasticity. This might help to explain dopaminergic effect on cognition and could be relevant for understanding the pathophysiology and treatment of neuropsychiatric diseases accompanied by alterations of the dopaminergic system.

Does long term use of piracetam improve speech disturbances due to ischemic cerebrovascular diseases?

Aphasia causes significant disability and handicap among stroke survivors. Language therapy is recommended for aphasic patients, but not always available. Piracetam, an old drug with novel properties, has been shown to have mild beneficial effects on post-stroke aphasia. In the current study, we investigated the effects of 6 months treatment with piracetam on aphasia following stroke. Thirty patients with first-ever ischemic strokes and related aphasia were enrolled in the study. The scores for the National Institutes of Health Stroke Scale (NIHSS), Barthel Index (BI), modified Rankin Scale (mRS), and Gülhane Aphasia Test were recorded. The patients were scheduled randomly to receive either 4.8 g piracetam daily or placebo treatment for 6 months. At the end of 24 weeks, clinical assessments and aphasia tests were repeated. The level of improvement in the clinical parameters and aphasia scores was compared between the two groups. All patients had large lesions and severe aphasia. No significant difference was observed between the piracetam and placebo groups regarding the improvements in the NIHSS, BI and mRS scores at the end of the treatment. The improvements observed in spontaneous speech, reading fluency, auditory comprehension, reading comprehension, repetition, and naming were not significantly different in the piracetam and placebo groups, the difference reached significance only for auditory comprehension in favor of piracetam at the end of the treatment. Piracetam is well-tolerated in patients with post-stroke aphasia. Piracetam taken orally in a daily dose of 4.8 g for 6 months has no clear beneficial effect on post-stroke language disorders.

Fluoxetine for motor recovery after acute ischaemic stroke (FLAME): a randomised placebo-controlled trial

BACKGROUND

Hemiplegia and hemiparesis are the most common deficits caused by stroke. A few small clinical trials suggest that fluoxetine enhances motor recovery but its clinical efficacy is unknown. We therefore aimed to investigate whether fluoxetine would enhance motor recovery if given soon after an ischaemic stroke to patients who have motor deficits.

METHODS

In this double-blind, placebo-controlled trial, patients from nine stroke centres in France who had ischaemic stroke and hemiplegia or hemiparesis, had Fugl-Meyer motor scale (FMMS) scores of 55 or less, and were aged between 18 years and 85 years were eligible for inclusion. Patients were randomly assigned, using a computer random-number generator, in a 1:1 ratio to fluoxetine (20 mg once per day, orally) or placebo for 3 months starting 5-10 days after the onset of stroke. All patients had physiotherapy. The primary outcome measure was the change on the FMMS between day 0 and day 90 after the start of the study drug. Participants, carers, and physicians assessing the outcome were masked to group assignment. Analysis was of all patients for whom data were available (full analysis set). This trial is registered with ClinicalTrials.gov, number NCT00657163.

FINDINGS

118 patients were randomly assigned to fluoxetine (n=59) or placebo (n=59), and 113 were included in the analysis (57 in the fluoxetine group and 56 in the placebo group). Two patients died before day 90 and three withdrew from the study. FMMS improvement at day 90 was significantly greater in the fluoxetine group (adjusted mean 34·0 points [95% CI 29·7-38·4]) than in the placebo group (24·3 points [19·9-28·7]; p=0·003). The main adverse events in the fluoxetine and placebo groups were hyponatraemia (two [4%] vs two [4%]), transient digestive disorders including nausea, diarrhoea, and abdominal pain (14 [25%] vs six [11%]), hepatic enzyme disorders (five [9%] vs ten [18%]), psychiatric disorders (three [5%] vs four [7%]), insomnia (19 [33%] vs 20 [36%]), and partial seizure (one [<1%] vs 0).

INTERPRETATION

In patients with ischaemic stroke and moderate to severe motor deficit, the early prescription of fluoxetine with physiotherapy enhanced motor recovery after 3 months. Modulation of spontaneous brain plasticity by drugs is a promising pathway for treatment of patients with ischaemic stroke and moderate to severe motor deficit.

FUNDING

Public French National Programme for Clinical Research.

Crossover trial of subacute computerized aphasia therapy for anomia with the addition of either levodopa or placebo

BACKGROUND

The effect of levodopa on recovery from aphasia is controversial.

OBJECTIVE

To determine whether levodopa enhances the effect of intensive computer-assisted therapy (CAT) of anomia in the postacute stage of aphasia.

METHODS

Double-blind multiple case study with intrasubject crossover design comparing the effect of levodopa (100 mg) versus placebo, each given for 2 weeks.

SUBJECTS

Twelve patients with onset of aphasia from 2 to 9 weeks after stroke or traumatic brain injury were compared on naming performance on items trained and not trained with CAT. Subjects were randomized to either levodopa or placebo first, separated by a 1-week washout, and then switched to the other drug intervention for the second 2-week CAT intervention. The subjects also received routine aphasia therapies during these periods.

RESULTS

All patients improved their naming performance for items trained by CAT in both periods (P = .001). No significant difference was found between the placebo and levodopa phases.

CONCLUSION

Administration of levodopa for 2 weeks during the postacute stage of aphasia did not augment the positive effects of subacute intensive language treatment with CAT for a spoken naming task.

Awakenings and awareness recovery in disorders of consciousness: is there a role for drugs?

Disorders of consciousness (DOC) include coma, vegetative state (VS) and minimally conscious state (MCS). Coma is a condition of unarousability with a complete absence of wakefulness and awareness, whereas VS is characterized by a lack of awareness despite a preserved wakefulness. Patients in coma are unconscious because they lack both wakefulness and awareness. Patients in a VS are unconscious because, although they are wakeful, they lack awareness. Patients in a MCS show minimal but definite behavioural evidence of self and environmental awareness. Coma results from diffuse bilateral hemispheric lesions or selective damage to the ascending reticular system (which is functionally connected to the cerebral cortex by intralaminar thalamic nuclei). VS is a syndrome that is considered to be the result of a disconnection of different cortical networks rather than a dysfunction of a single area or a global reduction in cortical metabolism. As revealed by functional imaging studies, clinical recovery is often associated with a functional restoration of cortico-thalamo-cortical connections. Depending on the amount of network restored, patients may regain full consciousness or remain in a MCS. Molecular and neural mediators may indirectly contribute to the above restoration processes owing to their role in the phenomenon of neural synaptic plasticity. Therefore, there is growing interest in the possible effects of drugs that act at the level of the CNS in promoting emergence from DOC. Sporadic cases of dramatic recovery from DOC after the administration of various pharmacological agents, such as baclofen, zolpidem and amantadine, have been recently supported by intriguing scientific observations. Analysis of the reported cases of recovery, with particular attention paid to the condition of the patients and to the association of their improvement with the start of drug administration, suggests that these treatments might have promoted the clinical improvement of some patients. These drugs are from various and diverging classes, but can be grouped into two main categories, CNS stimulants and CNS depressants. Some of these treatments seem to directly encourage a consciousness restoration, while others play a more determinant role in improving cognitive domains, especially in patients with residual cognitive impairment, than in the field of consciousness. Given the great interest recently generated in the scientific community by the increasing number of papers addressing this issue, further investigation of the above treatments, with particular attention paid to their mechanisms of action, the neurotransmitters involved and their effects on cortico-thalamo-cortical circuitry, is needed.

Dosage-dependent non-linear effect of L-dopa on human motor cortex plasticity

The neuromodulator dopamine affects learning and memory formation and their likely physiological correlates, long-term depression and potentiation, in animals and humans. It is known from animal experiments that dopamine exerts a dosage-dependent, inverted U-shaped effect on these functions. However, this has not been explored in humans so far. In order to reveal a non-linear dose-dependent effect of dopamine on cortical plasticity in humans, we explored the impact of 25, 100 and 200 mg of L-dopa on transcranial direct current (tDCS)-induced plasticity in twelve healthy human subjects. The primary motor cortex served as a model system, and plasticity was monitored by motor evoked potential amplitudes elicited by transcranial magnetic stimulation. As compared to placebo medication, low and high dosages of L-dopa abolished facilitatory as well as inhibitory plasticity, whereas the medium dosage prolonged inhibitory plasticity, and turned facilitatory plasticity into inhibition. Thus the results show clear non-linear, dosage-dependent effects of dopamine on both facilitatory and inhibitory plasticity, and support the assumption of the importance of a specific dosage of dopamine optimally suited to improve plasticity. This might be important for the therapeutic application of dopaminergic agents, especially for rehabilitative purposes, and explain some opposing results in former studies.

Long-term motor improvement after stroke is enhanced by short-term treatment with the alpha-2 antagonist, atipamezole

Drugs that increase central noradrenergic activity have been shown to enhance the rate of recovery of motor function in pre-clinical models of brain damage. Less is known about whether noradrenergic agents can improve the extent of motor recovery and whether such improvement can be sustained over time. This study was designed to determine if increasing central noradrenergic tone using atipamezole, an alpha-2 adrenoceptor antagonist, could induce a long-term improvement in motor performance in rats subjected to ischemic brain damage caused by permanent middle cerebral artery occlusion. The importance of pairing physical "rehabilitation" with enhanced noradrenergic activity was also investigated. Atipamezole (1 mg/kg, s.c.) or vehicle (sterile saline) was administered once daily on Days 2-8 post-operatively. Half of each drug group was housed under enriched environment conditions supplemented with daily focused activity sessions while the other half received standard housing with no focused activity. Skilled motor performance in forelimb reaching and ladder rung walking was assessed for 8 weeks post-operatively. Animals receiving atipamezole plus rehabilitation exhibited significantly greater motor improvement in both behavioral tests as compared to vehicle-treated animals receiving rehabilitation. Interestingly, animals receiving atipamezole without rehabilitation exhibited a significant motor improvement in the ladder rung walk test but not the forelimb reaching test. These results suggest that a short-term increase in noradrenergic activity can lead to sustained motor improvement following stroke, especially when paired with rehabilitation.

Cell Therapy From Bench to Bedside Translation in CNS Neurorestoratology Era

Recent advances in cell biology, neural injury and repair, and the progress towards development of neurorestorative interventions are the basis for increased optimism. Based on the complexity of the processes of demyelination and remyelination, degeneration and regeneration, damage and repair, functional loss and recovery, it would be expected that effective therapeutic approaches will require a combination of strategies encompassing neuroplasticity, immunomodulation, neuroprotection, neurorepair, neuroreplacement, and neuromodulation. Cell-based restorative treatment has become a new trend, and increasing data worldwide have strongly proven that it has a pivotal therapeutic value in CNS disease. Moreover, functional neurorestoration has been achieved to a certain extent in the CNS clinically. Up to now, the cells successfully used in preclinical experiments and/or clinical trial/treatment include fetal/embryonic brain and spinal cord tissue, stem cells (embryonic stem cells, neural stem/progenitor cells, hematopoietic stem cells, adipose-derived adult stem/precursor cells, skin-derived precursor, induced pluripotent stem cells), glial cells (Schwann cells, oligodendrocyte, olfactory ensheathing cells, astrocytes, microglia, tanycytes), neuronal cells (various phenotypic neurons and Purkinje cells), mesenchymal stromal cells originating from bone marrow, umbilical cord, and umbilical cord blood, epithelial cells derived from the layer of retina and amnion, menstrual blood-derived stem cells, Sertoli cells, and active macrophages, etc. Proof-of-concept indicates that we have now entered a new era in neurorestoratology.

Effects of methylphenidate on cerebral glucose metabolism in patients with impaired consciousness after acquired brain injury

OBJECTIVES

To evaluate the effects of methylphenidate on cerebral glucose metabolism in patients with impaired consciousness after acquired brain injury.

METHODS

Fourteen patients with impaired consciousness after acquired brain injury were enrolled in our study. We evaluated the level of consciousness with the Glasgow Coma Scale upon initial evaluation and at the 6-week follow-up after methylphenidate medication (0.3 mg/kg per day, which was administered twice daily). Positron emission tomography was performed before and after 6 weeks of medication, and the effects of methylphenidate on cerebral glucose metabolism were analyzed using statistical parametric mapping.

RESULTS

The statistical parametric mapping analysis indicated that significant increases of the cerebral glucose metabolism after methylphenidate therapy, compared with the initial positron emission tomographic image, were most evident in the left precuneus, the right posterior cingulated and the right retrosplenial cortices, and the right inferior parietal cortex (P < 0.001). In addition, cerebral glucose metabolism was significantly increased in the right precuneus, the right superior and middle temporal gyri, and bilateral middle occipital gyri (P < 0.005). In the correlation analysis, improvement of the Glasgow Coma Scale scores after methylphenidate medication was significantly associated with increased cerebral glucose metabolism in the bilateral precuneus, the bilateral middle occipital gyri, and right middle frontal gyrus.

CONCLUSIONS

Our findings suggest that the posteromedial parietal cortex, which is part of the neural network for consciousness, may be the relevant structure for the pharmacological response to methylphenidate treatment in patients with impaired consciousness after acquired brain injury.

Pharmacotherapy in stroke rehabilitation

BACKGROUND

Pharmacotherapy is commonly given to patients recovering from a stroke to prevent further complications (e.g. recurrent stroke, seizures) or enhance recovery. However, some drugs may have a negative impact on neuroplasticity.

OBJECTIVES

This review examines currently used drugs that are believed to promote recovery from motor and cognitive disturbances associated with stroke.

METHODS

Literature regarding the properties, efficacy, safety, and dosing of drugs used to promote recovery after stroke was reviewed.

RESULTS

The data on pharmacotherapy are insufficient to support a claim of significantly improved rehabilitation outcomes. Moreover, a growing body of evidence indicates that some agents can impair functional reorganization and slow the recovery process. However, a few chemicals are reported to be beneficial for stroke rehabilitation. The most promising are noradrenergic and dopaminergic agents, as well as several growth factors; these should be the future focus of extensive randomized clinical trials.

CONCLUSIONS

Currently there is no drug with proven efficacy in enhancing poststroke recovery.

Recovery of function in humans: cortical stimulation and pharmacological treatments after stroke

In this contribution, we first provide an overview of general principles of reorganisation in the human brain, and point out possible biomarkers of recovery. Subsequently, we expand on possibilities of adjuvant therapy in human rehabilitation using cortical stimulation and pharmacological treatments. Finally, we suggest future directions for research in this field.

Recent advances in rehabilitation of stroke survivors

This report discusses the newest approaches to rehabilitation of post-stroke patients. Recent studies have clinical implications for the treatment of stroke at all stages, and chronic aphasia.