Topical Therapy with Mesenchymal Stem Cells Following an Acute Experimental Head Injury Has Benefits in Motor-Behavioral Tests for Rodents

Systematic review and meta-analysis of preclinical studies testing mesenchymal stromal cells for traumatic brain injury

Mesenchymal stromal cells (MSCs) are widely used in preclinical models of traumatic brain injury (TBI). Results are promising in terms of neurological improvement but are hampered by wide variability in treatment responses. We made a systematic review and meta-analysis: (1) to assess the quality of evidence for MSC treatment in TBI rodent models; (2) to determine the effect size of MSCs on sensorimotor function, cognitive function, and anatomical damage; (3) to identify MSC-related and protocol-related variables associated with greater efficacy; (4) to understand whether MSC manipulations boost therapeutic efficacy. The meta-analysis included 80 studies. After TBI, MSCs improved sensorimotor and cognitive deficits and reduced anatomical damage. Stratified meta-analysis on sensorimotor outcome showed similar efficacy for different MSC sources and for syngeneic or xenogenic transplants. Efficacy was greater when MSCs were delivered in the first-week post-injury, and when implanted directly into the lesion cavity. The greatest effect size was for cells embedded in matrices or for MSC-derivatives. MSC therapy is effective in preclinical TBI models, improving sensorimotor, cognitive, and anatomical outcomes, with large effect sizes. These findings support clinical studies in TBI.

Cell-Based Therapies for Traumatic Brain Injury: Therapeutic Treatments and Clinical Trials

Traumatic brain injury (TBI) represents physical damage to the brain tissue that induces transitory or permanent neurological disabilities. TBI contributes to 50% of all trauma deaths, with many enduring long-term consequences and significant medical and rehabilitation costs. There is currently no therapy to reverse the effects associated with TBI. An increasing amount of research has been undertaken regarding the use of different stem cells (SCs) to treat the consequences of brain damage. Neural stem cells (NSCs) (adult and embryonic) and mesenchymal stromal cells (MSCs) have shown efficacy in pre-clinical models of TBI and in their introduction to clinical research. The purpose of this review is to provide an overview of TBI and the state of clinical trials aimed at evaluating the use of stem cell-based therapies in TBI. The primary aim of these studies is to investigate the safety and efficacy of the use of SCs to treat this disease. Although an increasing number of studies are being carried out, few results are currently available. In addition, we present our research regarding the use of cell therapy in TBI. There is still a significant lack of understanding regarding the cell therapy mechanisms for the treatment of TBI. Thus, future studies are needed to evaluate the feasibility of the transplantation of SCs in TBI.

Neuroprotective effect of Da Chuanxiong Formula against cognitive and motor deficits in a rat controlled cortical impact model of traumatic brain injury

ETHNOPHARMACOLOGICAL RELEVANCE

Da Chuanxiong Formula (DCXF) is one of the famous herb pairs that contains dried rhizomes of Ligusticum chuanxiong Hort. and Gastrodia elata Bl. in the mass ratio of 4:1. This classic representative traditional Chinese medicine has been widely used to treat brain diseases like headache and migraine caused by blood stasis and wind pathogen. However, the therapeutic effect of DCXF on traumatic brain injury (TBI) has not been reported yet.

AIM OF STUDY

The present study was performed to investigate the neuroprotective effects of DCXF and its underlying mechanisms in the controlled cortical impact (CCI)-induced TBI rat model.

MATERIALS AND METHODS

Male Sprague-Dawley rats were divided into four groups: Sham, TBI control, 1X DCXF (520.6 mg/kg) and 5X DCXF (2603.0 mg/kg). Two treatment groups (1X and 5X DCXF) were intragastrically administered daily for 7 days before CCI-induced TBI and then DCXF treatments were continued post-TBI until the animal behavioral tests, including Morris water maze test, acceleration rotarod motor test and CatWalk quantitative gait analysis test, were done. The brain water content and blood brain barrier (BBB) integrity were measured by wet-dry weight method and Evans blue method, respectively. The number of neuron cells, neural stem cells (NSCs), GFAP positive cells (astrocyte) as well as Iba-1 positive cells (microglia) were determined by histology and immunohistochemistry.

RESULTS

Treatment with DCXF significantly improved the learning ability and memory retention in Morris water maze test, and remarkably enhanced motor performances in acceleration rotarod motor test and catwalk quantitative gait analysis test after TBI. Moreover, DCXF treatment was able to reduce BBB permeability, brain edema, microglia and astrocyte activation, improve the proliferation of NSCs and decrease neurons loss in the brain with TBI.

CONCLUSIONS

The present study demonstrated that DCXF treatment could decrease BBB leakage and brain edema, reduce neuron loss, microglia and astrocyte activation, and increase NSCs proliferation, which may contribute to the cognitive and motor protection of DCXF in the TBI rats. It is the first time to provide potentially underlying mechanisms of the neuroprotective effect of DCXF on TBI-induced brain damage and functional outcomes.

Implantation of Neuronal Stem Cells Enhances Object Recognition without Increasing Neurogenesis after Lateral Fluid Percussion Injury in Mice

Cognitive deficits after traumatic brain injury (TBI) are debilitating and contribute to the morbidity and loss of productivity of over 10 million people worldwide. Cell transplantation has been linked to enhanced cognitive function after experimental traumatic brain injury, yet the mechanism of recovery is poorly understood. Since the hippocampus is a critical structure for learning and memory, supports adult neurogenesis, and is particularly vulnerable after TBI, we hypothesized that stem cell transplantation after TBI enhances cognitive recovery by modulation of endogenous hippocampal neurogenesis. We performed lateral fluid percussion injury (LFPI) in adult mice and transplanted embryonic stem cell-derived neural progenitor cells (NPC). Our data confirm an injury-induced cognitive deficit in novel object recognition, a hippocampal-dependent learning task, which is reversed one week after NPC transplantation. While LFPI alone promotes hippocampal neurogenesis, as revealed by doublecortin immunolabeling of immature neurons, subsequent NPC transplantation prevents increased neurogenesis and is not associated with morphological maturation of endogenous injury-induced immature neurons. Thus, NPC transplantation enhances cognitive recovery early after LFPI without a concomitant increase in neuron numbers or maturation.

Docosahexaenoic acid (DHA) enhances the therapeutic potential of neonatal neural stem cell transplantation post-Traumatic brain injury

Traumatic Brain Injury (TBI) is a major cause of death and disability worldwide with 1.5 million people inflicted yearly. Several neurotherapeutic interventions have been proposed including drug administration as well as cellular therapy involving neural stem cells (NSCs). Among the proposed drugs is docosahexaenoic acid (DHA), a polyunsaturated fatty acid, exhibiting neuroprotective properties. In this study, we utilized an innovative intervention of neonatal NSCs transplantation in combination with DHA injections in order to ameliorate brain damage and promote functional recovery in an experimental model of TBI. Thus, NSCs derived from the subventricular zone of neonatal pups were cultured into neurospheres and transplanted in the cortex of an experimentally controlled cortical impact mouse model of TBI. The effect of NSC transplantation was assessed alone and/or in combination with DHA administration. Motor deficits were evaluated using pole climbing and rotarod tests. Using immunohistochemistry, the effect of transplanted NSCs and DHA treatment was used to assess astrocytic (Glial fibrillary acidic protein, GFAP) and microglial (ionized calcium binding adaptor molecule-1, IBA-1) activity. In addition, we quantified neuroblasts (doublecortin; DCX) and dopaminergic neurons (tyrosine hydroxylase; TH) expression levels. Combined NSC transplantation and DHA injections significantly attenuated TBI-induced motor function deficits (pole climbing test), promoted neurogenesis, coupled with an increase in glial reactivity at the cortical site of injury. In addition, the number of tyrosine hydroxylase positive neurons was found to increase markedly in the ventral tegmental area and substantia nigra in the combination therapy group. Immunoblotting analysis indicated that DHA+NSCs treated animals showed decreased levels of 38kDa GFAP-BDP (breakdown product) and 145kDa αII-spectrin SBDP indicative of attenuated calpain/caspase activation. These data demonstrate that prior treatment with DHA may be a desirable strategy to improve the therapeutic efficacy of NSC transplantation in TBI.