Effects of Central Nervous System Drugs on Recovery After Stroke: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

A systematic-search-and-review of registered pharmacological therapies investigated to improve neuro-recovery after a stroke

Background

Stroke burden is largely due to long-term impairments requiring prolonged care with loss of productivity. We aimed to identify and assess studies of different registered pharmacological therapies as treatments to improve post-stroke impairments and/or disabilities.

Methods

We performed a systematic-search-and-review of treatments that have been investigated as recovery-enhancing or recovery-promoting therapies in adult patients with stroke. The treatment must have received registration or market authorization in any country regardless of primary indication. Outcomes included in the review were neurological impairments and functional/disability assessments. "The best available studies" based on study design, study size, and/or date of publication were selected and graded for level of evidence (LOE) by consensus.

Results

Our systematic search yielded 7,801 citations, and we reviewed 665 full-text papers. Fifty-eight publications were selected as "the best studies" across 25 pharmacological classes: 31 on ischemic stroke, 21 on ischemic or hemorrhagic stroke, 4 on intracerebral hemorrhage, and 2 on subarachnoid hemorrhage (SAH). Twenty-six were systematic reviews/meta-analyses, 29 were randomized clinical trials (RCTs), and three were cohort studies. Only nimodipine for SAH had LOE A of benefit (systematic review and network meta-analysis). Many studies, some of which showed treatment effects, were assessed as LOE C-LD, mainly due to small sample sizes or poor quality. Seven interventions had LOE B-R (systematic review/meta-analysis or RCT) of treatment effects.

Conclusion

Only one commercially available treatment has LOE A for routine use in stroke. Further studies of putative neuroprotective drugs as adjunctive treatment to revascularization procedures and more confirmatory trials on recovery-promoting therapies will enhance the certainty of their benefit. The decision on their use must be guided by the clinical profile, neurological impairments, and target outcomes based on the available evidence.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=376973, PROSPERO, CRD42022376973.

Effect of Selective Serotonin Reuptake Inhibitors on Motor Recovery After Stroke: A Systematic Meta-analysis

OBJECTIVE

We conducted a meta-analysis to determine the effectiveness of selective serotonin reuptake inhibitors in improving motor outcomes after stroke. For accuracy, we only included studies in which selective serotonin reuptake inhibitors were administered to patients in the recovery phase after stroke (<6 mos after stroke).

DESIGN

Meta-analyses were conducted according to the tools used to measure motor function. We searched the SCOPUS, PubMed, Embase, and Cochrane Library databases for studies, which compared motor recovery in patients who receive selective serotonin reuptake inhibitor medication in the recovery phase after stroke with a control group that did not receive any selective serotonin reuptake inhibitor.

RESULTS

A total of 3715 publications were assessed, and nine studies met the study criteria. The group, which received selective serotonin reuptake inhibitors, showed improved Fugl-Meyer Motor Scale and Barthel index scores compared with the control group. However, there was no significant difference in the modified Rankin Scale scores between the selective serotonin reuptake inhibitor and control groups. The incidence of adverse effects after the administration of selective serotonin reuptake inhibitors did not differ from that in the control group.

CONCLUSIONS

Our study showed that the use of selective serotonin reuptake inhibitor in the recovery phase of stroke improved motor function without significant increase in adverse effects.

Recovery in Stroke Patients Treated With Fluoxetine Versus Placebo: A Pooled Analysis of 7,165 Patients

BACKGROUND

Stroke is a major cause of disability and death. Stroke recovery outcomes range from functional impairment to disability. This study was designed to compare the recovery results of stroke patients treated with fluoxetine to those treated with placebo.

REVIEW SUMMARY

Seventeen randomized clinical trials were identified by searching PubMed, Cochrane, Scopus, and Web of Science until June 2021. Fluoxetine enhances the National Institutes of Health Stroke Scale (NIHSS) score [mean difference (MD)=-0.67, 95% confidence interval (CI) (-1.19 to -0.15)] and the Fugl-Meyer Motor Scale (FMMS) score [MD=17.36, 95% CI (12.12-22.61)] at the 3-month follow up. However, the NIHSS score showed no significant difference between the 2 groups at 2 weeks [MD=-0.32, 95% CI (-0.72 to 0.07)] or at 6 months [MD=-0.17, 95% CI (-0.47 to 0.14)]. Fluoxetine-treated and placebo-treated patients had the same overall impact on FMMS scores at 1 month ( P =0.41). Barthel index showed no significant difference between the 2 arms at 3 months ( P =0.21) or 6 months ( P =0.68). Fluoxetine-treated patients were at a higher risk of broken bone [risk ratios (RR)=2.30, 95% CI (1.59-3.32)] and hyponatremia [RR=2.12, 95% CI (1.19-3.76)], and at lower risk of new depression [RR=0.72, 95% CI (0.61-0.84)] in comparison with placebo.

CONCLUSION

The efficacy of fluoxetine on the NIHSS and FMMS is likely to take time to emerge and is expected to be transient. The Barthel index score did not differ between the fluoxetine and placebo groups. The use of fluoxetine increased the incidence of hyponatremia and bone fractures while decreasing the risk of new-onset depression.

Delayed citalopram administration reduces brain inflammation and enhances skilled motor function after ischaemic stroke in 'MacGreen' mice

Recent evidence suggests that treatment with antidepressants may promote functional recovery. However, the timeframe in which these pharmacological agents can influence stroke recovery is not well understood. This research investigated whether delayed administration of citalopram, used clinically in the management of post-stroke depression, could improve long-term functional recovery following experimental stroke. MacGreen mice carrying an enhanced green fluorescent protein reporter gene in monocyte and macrophage populations were subjected to 45 min occlusion of the middle cerebral artery. Animals were administered citalopram (10 mg/kg/day, n = 20) or saline (n = 20) starting 3 days after stroke for 28 days. Neurological deficits and skilled motor performance in the staircase task were recorded for 9 weeks post stroke. Grey and white matter structural lesions were quantified at Week 9, and enhanced green fluorescent protein immunohistochemistry was used to evaluate the effect of citalopram on inflammation. Twenty-five animals were included in the final analysis. Citalopram-treated animals (n = 13) showed a significant increase in impaired forepaw use in the staircase task compared with saline-treated animals (n = 12) 2, 3 and 7 weeks post stroke but no difference in neurological score at any time point examined. Citalopram treatment was associated with decreased monocyte/macrophage cell density and increased white matter tract integrity within the ipsilateral cortex. In conclusion, delayed administration of citalopram decreased brain inflammation and produced functional gains in our mouse model of stroke. Beneficial effects on skilled motor functions were long-lasting.

Adjunctive cytoprotective therapies in acute ischemic stroke: a systematic review

With the introduction of endovascular thrombectomy (EVT), a new era for treatment of acute ischemic stroke (AIS) has arrived. However, despite the much larger recanalization rate as compared to thrombolysis alone, final outcome remains far from ideal. This raises the question if some of the previously tested neuroprotective drugs warrant re-evaluation, since these compounds were all tested in studies where large-vessel recanalization was rarely achieved in the acute phase. This review provides an overview of compounds tested in clinical AIS trials and gives insight into which of these drugs warrant a re-evaluation as an add-on therapy for AIS in the era of EVT. A literature search was performed using the search terms "ischemic stroke brain" in title/abstract, and additional filters. After exclusion of papers using pre-defined selection criteria, a total of 89 trials were eligible for review which reported on 56 unique compounds. Trial compounds were divided into 6 categories based on their perceived mode of action: systemic haemodynamics, excitotoxicity, neuro-inflammation, blood-brain barrier and vasogenic edema, oxidative and nitrosative stress, neurogenesis/-regeneration and -recovery. Main trial outcomes and safety issues are summarized and promising compounds for re-evaluation are highlighted. Looking at group effect, drugs intervening with oxidative and nitrosative stress and neurogenesis/-regeneration and -recovery appear to have a favourable safety profile and show the most promising results regarding efficacy. Finally, possible theories behind individual and group effects are discussed and recommendation for promising treatment strategies are described.

Intracerebral transplantation of autologous adipose-derived stem cells for chronic ischemic stroke: A phase I study

Current therapy does not provide significant benefits for patients with chronic stroke. Pre-clinical studies suggested that autologous adipose-derived stem cells have benefits for the treatment of chronic stroke. This Phase I open-label study was conducted to demonstrate the safety and efficacy of autologous adipose-derived stem cells (GXNPC1) in chronic stroke. Three patients with chronic stroke were treated with stereotactic implantation of autologous adipose-derived stem cells (1 × 10⁸ cells). The primary endpoints of safety evaluation included adverse events, over a 6 months post-implantation period. The secondary endpoints included improvements in neurological functions. Evolutional change of brain parenchyma was also followed with magnetic resonance imaging (MRI). All three participants improved significantly at 6 months follow-up. The extent of improvement from pre-treatment was: National Institutes of Health Stroke Scale improved 5-15 points, Barthel Index: 25-50 points, Berg balance scale 0-21 points and Fugl-Meyer modified sensation 3-28 points. All three patients had signal change along the implantation tract on MRI one month after surgery. There is no related safety issue through 6 months observation. Clinical measures of neurological symptoms of these patients with chronic stroke improved at 6 months without adverse effects after implantation of autologous adipose-derived stem cells (GXNPC1), which might be correlated with post-implantation changes on brain MRI. Clinical Trial Registration-URL: https://clinicaltrials.gov/ct2/show/NCT02813512?term=ADSC&cond=Stroke&cntry=TW&draw=2&rank=1 Unique identifier: NCT02813512.

Efficacy and tolerability of selective serotonin reuptake inhibitors on promoting motor recovery after stroke:meta-analysis of randomized controlled trials

INTRODUCTION

Although experimental data suggest that Selective serotonin reuptake inhibitors (SSRIs) may improve motor recovery after stroke, the results from clinical studies are conflicting.

AREAS COVERED

Six international electronic databases (Cochrane, PubMed, Embase, Web of Science, CINAHL, and PsycINFO) and four Chinese electronic databases (CBM, CNKI, WanFang Data, and VIP) were systematically searched up to April 2021. Co-primary outcomes were motor function and tolerability. Secondary outcomes included disability, neurological function, continuous depression scores, and adverse events.

RESULTS

25 randomized controlled trials including 4777 participants were identified. Pooled analyses found SSRIs significantly improved motor function [standardized mean differences (SMD), 0.72; 95% CI, 0.46 to 0.99], disability (SMD, 0.79; 95% CI, 0.51 to 1.06), neurological function (SMD, -0.58; 95% CI, -0.77 to -0.39) and continuous depression scores (SMD, -0.36; 95% CI, -0.70 to -0.02). SSRIs were associated with increased seizure (risk ratio, 9.00; 95% CI, 1.69 to 47.91) and gastrointestinal side effects (risk ratio, 2.26; 95% CI, 1.56 to 3.28), but similar risk of all-cause discontinuations when compared with the control group (risk ratio, 1.11; 95% CI, 0.79 to 1.56).

EXPERT OPINION

SSRIs are effective and well-tolerated to promote motor recovery after stroke, but may increase the risk of seizures and gastrointestinal adverse effects.

Endocrine disruptors also function as nervous disruptors and can be renamed endocrine and nervous disruptors (ENDs)

Endocrine disruption (ED) and endocrine disruptors (EDs) emerged as scientific concepts in 1995, after numerous chemical pollutants were found to be responsible for reproductive dysfunction. The World Health Organization established in the United Nations Environment Programme a list of materials, plasticizers, pesticides, and various pollutants synthesized from petrochemistry that impact not only reproduction, but also hormonal functions, directly or indirectly. Cells communicate via either chemical or electrical signals transmitted within the endocrine or nervous systems. To investigate whether hormone disruptors may also interfere directly or indirectly with the development or functioning of the nervous system through either a neuroendocrine or a more general mechanism, we examined the scientific literature to ascertain the effects of EDs on the nervous system, specifically in the categories of neurotoxicity, cognition, and behaviour. To date, we demonstrated that all of the 177 EDs identified internationally by WHO are known to have an impact on the nervous system. Furthermore, the precise mechanisms underlying this neurodisruption have also been established. It was previously believed that EDs primarily function via the thyroid. However, this study presents substantial evidence that approximately 80 % of EDs operate via other mechanisms. It thus outlines a novel concept: EDs are also neurodisruptors (NDs) and can be collectively termed endocrine and nervous disruptors (ENDs). Most of ENDs are derived from petroleum residues, and their various mechanisms of action are similar to those of "spam" in electronic communications technologies. Therefore, ENDs can be considered as an instance of spam in a biological context.

Pharmacological management of post-stroke depression: an update of the evidence and clinical guidance

Introduction: Post-stroke depression (PSD) is common, serious and of considerable high risk of being chronic. Pharmacological treatment is highly recommended (class I recommendation) based on level B evidence. Still, treatment is often insufficient and the diagnosis can be challenging.Areas covered: The present paper is an update on pharmacological treatment of PSD and a review of recent clinical guidelines. To put this into perspective, the authors highlight the risk factors that might help clinicians identify patients with PSD, and discuss pharmacological prevention, functional outcome, and safety of antidepressant treatment in stroke patients.Expert opinion: Although there are still gaps in our knowledge of PSD, the seriousness should not be neglected, and pharmacological treatment should be recommended when relevant. A selective serotonin reuptake inhibitor (SSRI) is first choice, but is not always tolerated or effective. Close follow-up and dose adjustments as well as add-on possibilities are therefore important aspects of treatment as well. Antidepressant treatment prevents PSD but the effect on enhancement of stroke recovery is less clear.

Revisiting Stem Cell-Based Clinical Trials for Ischemic Stroke

Stroke is the leading cause of serious long-term disability, significantly reducing mobility in almost half of the affected patients aged 65 years and older. There are currently no proven neurorestorative treatments for chronic stroke. To address the complex problem of restoring function in ischemic brain tissue, stem cell transplantation-based therapies have emerged as potential restorative therapies. Aligning with the major cell types found within the ischemic brain, stem-cell-based clinical trials for ischemic stroke have fallen under three broad cell lineages: hematopoietic, mesenchymal, and neural. In this review article, we will discuss the scientific rationale for transplanting cells from each of these lineages and provide an overview of published and ongoing trials using this framework.

The Independent and Interactive Associations of Bilingualism and Sex on Cognitive Performance in Hispanics/Latinos of the Hispanic Community Health Study/Study of Latinos

Sixty percent of Hispanics/Latinos are bilingual which research suggests may confer certain cognitive advantages. Female sex confers cognitive advantages in verbal learning and memory compared to male sex, regardless of race or ethnicity. Understanding the independent and interactive associations of bilingualism and sex with cognition may aid in predicting cognitive aging in Hispanics/Latinos. We examined baseline (2008-2011) data from the Hispanic Community Health Study/Study of Latinos, a multicenter, prospective community-based study. Our analyses included 6,110 males and females ≥45 years old who self-reported birth and parents' origin outside of the continental US, Spanish as their first language, and were evaluated in Spanish. Bilingualism was assessed along a Likert scale (1 = only Spanish to 4 = English>Spanish) for language proficiency (reading/spoken) and patterns of use (thinking/socializing). Cognitive testing included verbal learning, memory, fluency, and Digit Symbol Substitution (DSS). Linear regression models adjusted for relevant confounders, the complex survey design, and sampling weights. Participants' self-reported language proficiency was Spanish better than English, while patterns of use suggested more Spanish than English. Higher language proficiency was associated with higher performance on all cognitive indices while higher patterns of use associated with higher fluency and DSS scores (p-values < 0.01). Female sex was associated with higher performance on all cognitive indices (p-values < 0.05). There were no significant interactions with bilingualism (regardless of metric) by sex on cognition. For Hispanics/Latinos residing in the continental US and reporting birth and parents' origin elsewhere, bilingualism and female sex have independent cognitive benefits that are important to consider when evaluating cognitive performance.

Anticholinergic and Sedative Drug Burden and Functional Recovery after Cerebrovascular Accident: A Retrospective Descriptive Study

Objectives:

Medications with anticholinergic or sedative effects induce impaired cognitive and physical performances. The aim of this study was to evaluate the associations of anticholinergic and sedative drug burden with recovery of physical function and activities of daily living in patients admitted to a Japanese rehabilitation hospital after cerebrovascular accidents.

Methods:

We retrospectively reviewed the medical records of patients aged 18 years or older who had undergone the inpatient rehabilitation program for cerebrovascular disease in Nerima Ken-ikukai Hospital. Patients who did not complete the rehabilitation program because of acute unexpected changes of physical or psychological condition or the need for surgical procedures were excluded. The primary outcome was recovery of activities of daily living as measured by the motor and cognitive subscores of the Functional Independence Measure. The secondary outcome was recovery of physical function as assessed by the 10-m walk test and the Berg balance scale. Multiple Cox proportional hazard regression analyses were conducted to calculate hazard ratios with 95% confidence intervals for the outcome measures.

Results:

Of 122 patients included in the study, 81 (66%) were exposed to anticholinergics and sedatives. Patients’ age, body mass index, and average daily drug burden during hospitalization were independently associated with achieving the cutoff Functional Independence Measure–motor subscore. Patients’ age and average daily drug burden during hospitalization were independently associated with achieving the Berg balance scale cut-off score.

Conclusions:

Our study of Japanese patients who were transferred from acute stroke care hospitals to a rehabilitation facility identified the drug burden of anticholinergics and sedatives as an independent factor associated with the time to recovery of activities of daily living and postural balance.

Use of Selective Serotonin Reuptake Inhibitors and Outcomes in Stroke Rehabilitation: A Prospective Observational Pilot Cohort Study

Purpose

The aim of this study was to examine the association between selective serotonin reuptake inhibitor (SSRI) therapy and rehabilitation outcomes, specifically disability and quality of life (QOL), in a real-world setting of multi-ethnic Asian patients with first-ever stroke.

Methods

In this prospective observational pilot cohort study, we included patients with first-ever stroke admitted to two inpatient rehabilitation centres in Singapore between January and July 2018. Outcomes were measured using Functional Independence Measure (FIM)-motor scale, modified Barthel Index (MBI) and the Stroke and Aphasia Quality of Life Scale-39 generic (SAQOL-39g) questionnaire. Linear regression was used to assess the association between SSRI therapy and outcomes. Regression coefficients and 95% confidence intervals (CIs) were reported.

Results

Among 57 patients included for analyses, 38.6% received SSRIs. Although SSRI therapy was significantly associated with gains in MBI (coefficient 11.35; 95% CI 0.21–22.50) and SAQOL-39g overall score (coefficient 0.45; 95% CI 0.05–0.85) based on simple linear regression, no significant association between SSRI therapy and any of the investigated outcomes was found after adjustment for confounders. However, an increase in the mean number of physiotherapy and occupational therapy (PT/OT) sessions per day significantly improved FIM-motor (coefficient 16.86; 95% CI 2.64–31.07) and MBI (coefficient 22.79; 95% CI 2.35–43.23) scores.

Conclusion

SSRI therapy did not improve disability and QOL in multi-ethnic Asian patients with first-ever stroke undergoing rehabilitation.

Electronic supplementary material

The online version of this article (10.1007/s40268-019-00287-y) contains supplementary material, which is available to authorized users.

Associations of Lipid Levels and Cognition: Findings from the Hispanic Community Health Study/Study of Latinos

OBJECTIVE

Hispanics/Latinos in the United States are less aware of their cholesterol levels and have a higher burden of associated adverse cardiovascular and cerebrovascular outcomes than non-Latino whites. Investigations of the associations between cholesterol levels and cognition in this population have often occurred within the context of metabolic syndrome and are limited to select lipids despite the fact that triglycerides (TGs) may be more relevant to the health of Hispanics/Latinos.

METHODS

Baseline data from the Hispanic Community Health Study/Study of Latinos, collected from 2008 to 2011, was used to investigate the associations of lipid levels (i.e., TG, total cholesterol, TC; low-density and high-density lipoprotein cholesterol, LDL-C and HDL-C) with cognition (i.e., learning, memory, verbal fluency, and digit symbol substitution, DSS), adjusting for relevant confounders.

RESULTS

In 7413 participants ages 45 to 74 years from Central American, Cuban, Dominican, Mexican, Puerto Rican, and South American backgrounds, separate, fully adjusted linear regression models revealed that TG levels were inversely associated with DSS performance; however, this relationship was no longer significant once additional cardiovascular disease risk factors were added to the model (p = .06). TC and LDL-C levels (separately) were positively associated with learning and verbal fluency regardless of adjustments (p-values < .05). Separate analyses investigating the effect modification by background and sex revealed a particularly robust association between TC levels and DSS performance for Puerto Ricans and Central Americans (albeit in opposite directions) and an inverse relationship between TG levels and DSS performance for women (p-values < .02).

CONCLUSIONS

It is important to consider individual lipid levels and demographic characteristics when investigating associations between cholesterol levels and cognition in Hispanics/Latinos.

Fluoxetine for motor recovery after acute intracerebral hemorrhage, the FMRICH trial

OBJECTIVES

Acute intracerebral hemorrhage (ICH) is a very common cause of disability. Previous evidence suggests that fluoxetine and other selective serotonin reuptake inhibitors improve, the recovery of motor function in patients with cerebral infarct. The purpose of this study was to investigate whether fluoxetine also improves motor recovery in patients with ICH.

PATIENTS AND METHODS

This is a double blind, placebo controlled, multicenter randomized trial, patients recruited from three centers were assigned to receive 20 mg/day of fluoxetine or matching placebo for three months from within ten days after onset of symptoms. Primary outcome was change in Fugl-Meyer Motor Scale from baseline to day 90.

RESULTS

Thirty patients (50 % women) were recruited to the fluoxetine (n = 14) or placebo (n = 16) groups. Median age was 55 years, the cause of the ICH was hypertension in 93.3 %, median volume of the hematomas was 22mm³. Basal ganglia hematoma was present in 67 % and, lobar location in 20 % of the patients. Improvement in FMMS at day 90 was significatively higher in the treatment group (median score 23) than in the placebo group, (median score 48), p = 0.001. No serious adverse events occurred.

CONCLUSION

In addition to standard treatment, early prescription of fluoxetine was safe and helped to increase motor recovery 90 days after ICH. This finding adds to the evidence regarding its beneficial effect upon stroke related disability. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01737541.

Post-stroke Depression Increases Disability More Than 15% in Ischemic Stroke Survivors: A Case-Control Study

We performed a retrospective, case-control study in consecutive ischemic stroke patients admitted to our stroke rehabilitation unit. Patients were matched for severity of neurological impairment (evaluated with the Canadian Neurological Scale, CNS), age (difference within 1 year), and onset admission interval (difference within 3 days). Participants were divided into two subgroups according to the presence or absence of PSD. Aim was to assess the specific influence of post-stroke depression (PSD) and antidepressant treatment on both basal functional status and rehabilitation outcomes. All PSD patients were treated primarily with serotoninergic antidepressants (AD). The final sample included 280 patients with depression (out of 320 found in a whole case series of 993 ischemic patients, i.e., 32.25%) and 280 without depression. Forty patients with depression were excluded because they had a history of severe psychiatric illness or aphasia, with a severe comprehension deficit. On one hand, PSD patients obtained lower Barthel Index (BI) and Rivermead Mobility Index (RMI) scores at both admission and discharge, with minor effectiveness of rehabilitative treatment and longer length of stay; on the other hand, this group had a lower percentage of dropouts. Lastly, PSD patients showed a different functional outcome, based on their response to antidepressant therapy, that was significantly better in responders than in non-responders (13.13%). Our results confirm the unfavorable influence of PSD on functional outcome, despite pharmacological treatment.

Dipeptidyl Peptidase-4 Inhibitors for the Potential Treatment of Brain Disorders; A Mini-Review With Special Focus on Linagliptin and Stroke

Cerebral stroke is a leading cause of death and persistent disability of elderly in the world. Although stroke prevention by targeting several risk factors such as diabetes and hypertension has decreased the stroke incidence, the total number of strokes is increasing due to the population aging and new preventive therapies are needed. Moreover, post-stroke acute pharmacological strategies aimed to reduce stroke-induced brain injury have failed in clinical trials despite being effective in animal models. Finally, approximately 30% of surviving stroke patients do not recover from stroke and remain permanently dependent on supportive care in activities of daily living. Therefore, strategies to improve stroke recovery in the post-acute phase are highly needed. Linagliptin is a dipeptidyl peptidase-4 inhibitor which is clinically approved to reduce hyperglycemia in type 2 diabetes. The regulation of glycemia by dipeptidyl peptidase-4 inhibition is mainly achieved by preventing endogenous glucagon-like peptide-1 (GLP-1) degradation. Interestingly, linagliptin has also shown glycaemia-independent beneficial effects in animal models of stroke, Parkinson's disease and Alzheimer's disease. In some case the preclinical data have been supported with some clinical data. Although potentially very interesting for the development of new strategies against stroke and neurodegenerative disorders, the mode of action of linagliptin in the brain is still largely unknown and seems to occur in a GLP-1R-independent manner. The purpose of this mini-review is to summarize and discuss the recent experimental and clinical work regarding the effects of linagliptin in the central nervous system, with special emphasis on acute neuroprotection, stroke prevention and post-stroke recovery. We also highlight the main questions in this research field that need to be addressed in clinical perspective.

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.

Potential Role of Selective Serotonin Reuptake Inhibitors in Improving Functional Outcome after Stroke

The great advances in acute stroke treatment during the last decades have changed life after stroke considerably. However, the use of intravenous thrombolysis and endovascular thrombectomy is limited by a relatively narrow time window or contraindications for treatment. Further, patients receiving acute reperfusion therapies may still have cognitive and emotional complications due to underlying brain infarcts even though physical problems may almost disappear. Consequently, stroke is still a frequent cause of adult disability and death worldwide, and an effort to identify additional treatments to enhance recovery, preferably also feasible in the time after the acute phase, is warranted. Albeit several drugs and treatment modalities have been studied for their potential to enhance recovery after stroke, no treatment has unambiguously proven to potentiate the rehabilitation process. A promising candidate for pharmacological treatment is selective serotonin reuptake inhibitors (SSRIs), a group of commonly used antidepressants that may also possess neuro-regenerative properties. The current paper reviews the evidence for SSRIs as potential enhancers of stroke recovery and discusses the potential mechanisms behind the effects reported and the implications for the management of patients post-stoke, including potential adverse events and drug-drug interactions.

Pharmacokinetic Study of Piracetam in Focal Cerebral Ischemic Rats

BACKGROUND AND OBJECTIVE

Cerebral ischemia affects hepatic enzymes and brain permeability extensively. Piracetam was investigated up to phase III of clinical trials and there is lack of data on brain penetration in cerebral ischemic condition. Thus, knowledge of the pharmacokinetics and brain penetration of piracetam during ischemic condition would aid to improve pharmacotherapeutics in ischemic stroke.

METHODS

Focal cerebral ischemia was induced by middle cerebral artery occlusion for 2 h in male Wistar rats followed by reperfusion. After 24 h of middle cerebral artery occlusion or 22 h of reperfusion, piracetam was administered for pharmacokinetic, brain penetration, and pharmacological experiments. In pharmacokinetic study, blood samples were collected at different time points after 200-mg/kg (oral) and 75-mg/kg (intravenous) administration of piracetam through right external jugular vein cannulation. In brain penetration study, the cerebrospinal fluid, systemic blood, portal blood, and brain samples were collected at pre-designated time points after 200-mg/kg oral administration of piracetam. In a separate experiment, the pharmacological effect of the single oral dose of piracetam in middle cerebral artery occlusion was assessed at a dose of 200 mg/kg.

RESULTS

All the pharmacokinetic parameters of piracetam including area under curve (AUC_0-24), maximum plasma concentration (C _max), time to reach the maximum plasma concentration (t _max), elimination half-life (t _1/2), volume of distribution (V _z), total body clearance, mean residence time, and bioavailability were found to be similar in ischemic stroke condition except for brain penetration. Piracetam exposure (AUC_0-2) in brain and CSF were found to be 2.4- and 3.1-fold higher, respectively, in ischemic stroke compared to control rats. Piracetam significantly reduced infarct volume by 35.77% caused by middle cerebral artery occlusion.

CONCLUSIONS

There was no change in the pharmacokinetic parameters of piracetam in the ischemic stroke model except for brain penetration. This indicates that variables influencing brain penetration may not be limiting factors for use of piracetam in ischemic stroke.