Probing Interleukin-6 in Stroke Pathology and Neural Stem Cell Transplantation

Emerging strategies for nerve repair and regeneration in ischemic stroke: neural stem cell therapy

Ischemic stroke is a major cause of mortality and disability worldwide, with limited treatment options available in clinical practice. The emergence of stem cell therapy has provided new hope to the field of stroke treatment via the restoration of brain neuron function. Exogenous neural stem cells are beneficial not only in cell replacement but also through the bystander effect. Neural stem cells regulate multiple physiological responses, including nerve repair, endogenous regeneration, immune function, and blood-brain barrier permeability, through the secretion of bioactive substances, including extracellular vesicles/exosomes. However, due to the complex microenvironment of ischemic cerebrovascular events and the low survival rate of neural stem cells following transplantation, limitations in the treatment effect remain unresolved. In this paper, we provide a detailed summary of the potential mechanisms of neural stem cell therapy for the treatment of ischemic stroke, review current neural stem cell therapeutic strategies and clinical trial results, and summarize the latest advancements in neural stem cell engineering to improve the survival rate of neural stem cells. We hope that this review could help provide insight into the therapeutic potential of neural stem cells and guide future scientific endeavors on neural stem cells.

Inflammatory marker profiles and in-hospital neurological deterioration in patients with acute minor ischemic stroke

AIM

The aim of the study was to analyze the association between inflammatory marker profiles and in-hospital neurological deterioration (ND) in acute ischemic stroke (AIS) patients.

METHODS

Data from patients with minor AIS from the Third China National Stroke Registry were analyzed. Inflammatory cytokine levels within 24 h of admission were measured. The primary outcome was in-hospital ND (an increase in National Institutes of Health Stroke Scale score ≥4 from admission to discharge). Associations were evaluated using odds ratios (ORs) and 95% confidence intervals (CIs) derived from logistic regression models. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were used to evaluate incremental predictive values.

RESULTS

A total of 4031 patients (1246 women, 30.9%) with a median age of 62 years were included. In-hospital ND occurred in 121 patients (3%). Each standard-deviation increase in interleukin (IL)-6 (OR, 1.17 [95% CI, 1.06-1.31]) and high-sensitivity C-reactive protein (hsCRP) (OR, 1.43 [95% CI, 1.24-1.66]) levels was associated with increased in-hospital ND risk. Incremental predictive values for adding IL-6 (IDI, 0.012; NRI, 0.329) but not hsCRP levels to the conventional risk factors were found.

CONCLUSION

In minor AIS, hsCRP and IL-6 levels were associated with in-hospital ND, including IL-6 levels in prognostic models improved risk classification.

Stem cell-based ischemic stroke therapy: Novel modifications and clinical challenges

Ischemic stroke (IS) causes severe disability and high mortality worldwide. Stem cell (SC) therapy exhibits unique therapeutic potential for IS that differs from current treatments. SC's cell homing, differentiation and paracrine abilities give hope for neuroprotection. Recent studies on SC modification have enhanced therapeutic effects for IS, including gene transfection, nanoparticle modification, biomaterial modification and pretreatment. These methods improve survival rate, homing, neural differentiation, and paracrine abilities in ischemic areas. However, many problems must be resolved before SC therapy can be clinically applied. These issues include production quality and quantity, stability during transportation and storage, as well as usage regulations. Herein, we reviewed the brief pathogenesis of IS, the "multi-mechanism" advantages of SCs for treating IS, various SC modification methods, and SC therapy challenges. We aim to uncover the potential and overcome the challenges of using SCs for treating IS and convey innovative ideas for modifying SCs.

Attenuation of amyotrophic lateral sclerosis via stem cell and extracellular vesicle therapy: An updated review

Amyotrophic lateral sclerosis (ALS) is a rapidly fatal neurological disease characterized by upper and lower motor neuron degeneration. Though typically idiopathic, familial forms of ALS are commonly comprised of a superoxide dismutase 1 (SOD1) mutation. Basic science frequently utilizes SOD1 models in vitro and in vivo to replicate ALS conditions. Therapies are sparse; those that exist on the market extend life minimally, thus driving the demand for research to identify novel therapeutics. Transplantation of stem cells is a promising approach for many diseases and has shown efficacy in SOD1 models and clinical trials. The underlying mechanism for stem cell therapy presents an exciting venue for research investigations. Most notably, the paracrine actions of stem cell-derived extracellular vesicles (EVs) have been suggested as a potent mitigating factor. This literature review focuses on the most recent preclinical research investigating cell-free methods for treating ALS. Various avenues are being explored, differing on the EV contents (protein, microRNA, etc.) and on the cell target (astrocyte, endothelial cell, motor neuron-like cells, etc.), and both molecular and behavioral outcomes are being examined. Unfortunately, EVs may also play a role in propagating ALS pathology. Nonetheless, the overarching goal remains clear; to identify efficient cell-free techniques to attenuate the deadly consequences of ALS.

Preconditioning Concepts for the Therapeutic Use of Extracellular Vesicles Against Stroke

Various preclinical stroke models have demonstrated the neuroprotective effects of extracellular vesicles (EVs) obtained from several types of cells, including neurons, astrocytes, microglia, neuronal progenitor cells, bone marrow stem cells, and mesenchymal stem cells. EVs interfere with key mechanisms in stroke pathophysiology such as cell death, neuroinflammation, autophagy, and angiogenesis. The mode of action and efficacy depend on the specific EV content, including miRNAs, proteins, and lipids, which can be modified through (I) bioengineering methods, (II) choice of source cells, and (III) modification of the source cell environment. Indeed, modifying the environment by preconditioning the EV-secreting cells with oxygen-glucose deprivation or medium modification revealed superior neuroprotective effects in stroke models. Although the concept of preconditioned EVs is relatively novel, it holds promise for the future treatment of ischemic stroke. Here, we give a brief overview about the main mechanisms of EV-induced neuroprotection and discuss the current status of preconditioning concepts for EV-treatment of ischemic stroke.