Effect of the monoaminergic stabiliser (-)-OSU6162 on mental fatigue following stroke or traumatic brain injury

Biomaterials and tissue engineering in traumatic brain injury: novel perspectives on promoting neural regeneration

Traumatic brain injury is a serious medical condition that can be attributed to falls, motor vehicle accidents, sports injuries and acts of violence, causing a series of neural injuries and neuropsychiatric symptoms. However, limited accessibility to the injury sites, complicated histological and anatomical structure, intricate cellular and extracellular milieu, lack of regenerative capacity in the native cells, vast variety of damage routes, and the insufficient time available for treatment have restricted the widespread application of several therapeutic methods in cases of central nervous system injury. Tissue engineering and regenerative medicine have emerged as innovative approaches in the field of nerve regeneration. By combining biomaterials, stem cells, and growth factors, these approaches have provided a platform for developing effective treatments for neural injuries, which can offer the potential to restore neural function, improve patient outcomes, and reduce the need for drugs and invasive surgical procedures. Biomaterials have shown advantages in promoting neural development, inhibiting glial scar formation, and providing a suitable biomimetic neural microenvironment, which makes their application promising in the field of neural regeneration. For instance, bioactive scaffolds loaded with stem cells can provide a biocompatible and biodegradable milieu. Furthermore, stem cells-derived exosomes combine the advantages of stem cells, avoid the risk of immune rejection, cooperate with biomaterials to enhance their biological functions, and exert stable functions, thereby inducing angiogenesis and neural regeneration in patients with traumatic brain injury and promoting the recovery of brain function. Unfortunately, biomaterials have shown positive effects in the laboratory, but when similar materials are used in clinical studies of human central nervous system regeneration, their efficacy is unsatisfactory. Here, we review the characteristics and properties of various bioactive materials, followed by the introduction of applications based on biochemistry and cell molecules, and discuss the emerging role of biomaterials in promoting neural regeneration. Further, we summarize the adaptive biomaterials infused with exosomes produced from stem cells and stem cells themselves for the treatment of traumatic brain injury. Finally, we present the main limitations of biomaterials for the treatment of traumatic brain injury and offer insights into their future potential.

Patients experience of cognitive fatigue post-stroke: an exploratory study

PURPOSE

Cognitive fatigue is commonly reported and described as disabling by patients recovering from neurological conditions including stroke. However, cognitive fatigue is usually underdiagnosed among stroke survivors which leads to a lack of specific treatments for this condition. Therefore, the aim of this study was to explore post-stroke cognitive fatigue as it is experienced by stroke survivors.

METHODS

This qualitative research followed the principles of descriptive phenomenology within a constructivist paradigm. Individual semi-structured interviews were conducted with stroke survivors experiencing post-stroke cognitive fatigue recruited through the Heart and Stroke Foundation, the Canadian Partnership for Stroke Recovery, and social media posts. Data were analyzed through inductive content analysis.

RESULTS

Eleven stroke survivors participated. The analysis revealed five themes illustrating the experience and descriptions of post-stroke cognitive fatigue: (1) characteristics, (2) aggravating factors, (3) management, (4) effect of cognitive fatigue on daily life, and (5) social awareness and support.

CONCLUSION

This study highlights the complexity of post-stroke cognitive fatigue. Cognitive fatigue becomes more evident after discharge; therefore, clinicians should consistently screen for it and provide proper education to the patients and their carers.IMPLICATIONS FOR REHABILITATIONCognitive fatigue is a complex phenomenon that can negatively affect the daily life of stroke survivors.Sensory-overloaded environments, emotional distress, poor sleep, and engaging in complex cognitive tasks can trigger post-stroke cognitive fatigue.More education on the concept of cognitive fatigue should be provided to healthcare providers to be able to identify and manage this symptom properly.

Processing Speed and Attentional Shift/Mental Flexibility in Patients with Stroke: A Comprehensive Review on the Trail Making Test in Stroke Studies

The Trail Making Test (TMT) is one of the most commonly administered tests in clinical and research neuropsychological settings. The two parts of the test (part A (TMT-A) and part B (TMT-B)) enable the evaluation of visuoperceptual tracking and processing speed (TMT-A), as well as divided attention, set-shifting and cognitive flexibility (TMT-B). The main cognitive processes that are assessed using TMT, i.e., processing speed, divided attention, and cognitive flexibility, are often affected in patients with stroke. Considering the wide use of TMT in research and clinical settings since its introduction in neuropsychological practice, the purpose of our review was to provide a comprehensive overview of the use of TMT in stroke patients. We present the most representative studies assessing processing speed and attentional shift/mental flexibility in stroke settings using TMT and applying scoring methods relying on conventional TMT scores (e.g., time-to-complete part A and part B), as well as derived measures (e.g., TMT-(B-A) difference score, TMT-(B/A) ratio score, errors in part A and part B). We summarize the cognitive processes commonly associated with TMT performance in stroke patients (e.g., executive functions), lesion characteristics and neuroanatomical underpinning of TMT performance post-stroke, the association between TMT performance and patients' instrumental activities of daily living, motor difficulties, speech difficulties, and mood statue, as well as their driving ability. We also highlight how TMT can serve as an objective marker of post-stroke cognitive recovery following the implementation of interventions. Our comprehensive review underscores that the TMT stands as an invaluable asset in the stroke assessment toolkit, contributing nuanced insights into diverse cognitive, functional, and emotional dimensions. As research progresses, continued exploration of the TMT potential across these domains is encouraged, fostering a deeper comprehension of post-stroke dynamics and enhancing patient-centered care across hospitals, rehabilitation centers, research institutions, and community health settings. Its integration into both research and clinical practice reaffirms TMT status as an indispensable instrument in stroke-related evaluations, enabling holistic insights that extend beyond traditional neurological assessments.

Systematic review: Pharmacological interventions for the treatment of post-stroke fatigue

BACKGROUND

Post-stroke fatigue (PSF) affects around 50% of stroke survivors. Previous systematic reviews of randomized controlled trials found insufficient evidence to guide practice, but most excluded Chinese studies. Furthermore, their searches are now out-of-date.

AIMS

To systematically review and perform a meta-analysis of randomized placebo-controlled trials of pharmacological interventions for treating PSF.

METHODS

We screened Airitri, CNKI, VIP, CINAHL, ClinicalTrials.gov, CENTRAL, Cochrane Stroke Group Trial Register, EMBASE, EU Clinical Trial Register, ISRCTN, MEDLINE, PsycINFO, Wanfang, and WHO ICTRP up to 11 November 2022. Our primary outcome was fatigue severity. We conducted subgroup analysis by drug type and sensitivity analysis after excluding the trials at high risk of bias. Secondary outcomes included mood and quality of life.

RESULTS

We screened 33,297 citations and identified 10 published completed trials, 6 unpublished completed trials, and 6 ongoing trials. Pharmacological treatments were associated with lower fatigue severity at the end of treatment (10 published completed trials, 600 participants, pooled standardized mean difference (SMD) = -0.80, 95% confidence interval (CI): -1.29 to -0.31; I2 = 86%, p < 0.00001), but not at follow-up (265 participants, pooled SMD = -0.14, 95% CI: -0.38 to 0.10; I2 = 0, p = 0.51). However, these trials were small and had considerable risk of bias. Beneficial effects were seen in trials with low risk of bias on randomization, missing outcome data, and reporting bias. There were insufficient data on secondary outcomes for meta-analysis, but six trials reported improved quality of life.

CONCLUSION

There is insufficient evidence to support a particular pharmacological treatment for PSF, thus current clinical guidelines do not require amendment.

(-)-OSU6162 in the treatment of fatigue and other sequelae after aneurysmal subarachnoid hemorrhage: a double-blind, randomized, placebo-controlled study

OBJECTIVE

Fatigue after aneurysmal subarachnoid hemorrhage (aSAH) is common and usually long-lasting, and it has a considerable negative impact on health-related quality of life (HRQOL), social functioning, and the ability to return to work (RTW). No effective treatment exists. The dopaminergic regulator (-)-OSU6162 has shown promising results regarding the mitigation of fatigue in various neurological diseases, and therefore the authors aimed to investigate the efficacy of (-)-OSU6162 in alleviating fatigue and other sequelae after aSAH.

METHODS

A double-blind, randomized, placebo-controlled, single-center trial was performed in which 96 participants with post-aSAH fatigue were administered 30-60 mg/day of (-)-OSU6162 or placebo over a period of 12 weeks. Efficacy was assessed using the Fatigue Severity Scale (FSS), the Mental Fatigue Scale (MFS), the Beck Anxiety Inventory (BAI), the Beck Depression Inventory II (BDI-II), the SF-36 questionnaire, and a neuropsychological test battery. Assessments were performed at baseline, after 1, 4, 8, and 12 weeks of treatment, and at follow-up, 8 weeks after treatment.

RESULTS

The 96 participants with post-aSAH fatigue were randomized to treatment with (-)-OSU6162 (n = 49) or placebo (n = 47). The FSS, MFS, and BDI scores improved significantly in both groups after 12 weeks of treatment, whereas the BAI scores improved in the placebo group only. HRQOL improved significantly in the SF-36 domain "Vitality" in both groups. Neuropsychological test performances were within the normal range at baseline and not affected by treatment. The FSS score was distinctly improved in patients with complete RTW upon treatment with (-)-OSU6162. Concomitant use of antidepressants improved the efficacy of (-)-OSU6162 on the FSS score at week 1 beyond the placebo response, and correspondingly the use of beta- or calcium-channel blockers improved the (-)-OSU6162 efficacy beyond the placebo response in MFS scores at week 4 of treatment. There was a significant correlation between improvement in FSS, BAI, and BDI scores and the plasma concentration of (-)-OSU6162 at the dose of 60 mg/day. No serious adverse events were attributable to the treatment, but dizziness was reported more often in the (-)-OSU6162 group.

CONCLUSIONS

Fatigue and other sequelae after aSAH were similarly alleviated by treatment with (-)-OSU6162 and placebo. (-)-OSU6162 improved fatigue, as measured with the FSS score, significantly in patients with complete RTW. There seemed to be synergetic effects of (-)-OSU6162 and medications interfering with dopaminergic pathways that should be explored further. The strong placebo response may be exploited in developing nonpharmacological treatment programs for post-aSAH fatigue.