Xenograft of Human Umbilical Mesenchymal Stem Cells Promotes Recovery from Chronic Ischemic Stroke in Rats

Efficacy and Potential Mechanisms of Umbilical Cord-Derived Mesenchymal Stem Cells in the Treatment of Ischemic Stroke in Animal Models: A Meta-Analysis

BACKGROUND

Umbilical cord-derived mesenchymal stem cells (UCMSCs) have emerged as a promising treatment for ischemic stroke. This study aimed to evaluate the therapeutic efficacy and potential mechanisms of UCMSCs in treating ischemic stroke.

METHODS

A systematic search of PubMed, Web of Science, and Embase was conducted up to April 25, 2024. Literature was screened based on the PICOS principle, with predefined inclusion and exclusion criteria. Relevant data were extracted and analyzed using Review Manager 5.4.

RESULTS

Out of 1390 retrieved articles, 30 were included in the meta-analysis. UCMSCs significantly reduced infarct size and volume, improved neurological deficit scores, and facilitated neurobehavioral recovery. UCMSCs treatment also modulated inflammatory cytokine levels in brain tissue and serum, promoted microglial polarization, inhibited apoptosis, and increased vessel density in the peri-infarct tissue.

CONCLUSIONS

UCMSCs administration significantly promoted the neurological function recovery after ischemic stroke. Their mechanisms of action may be related to immune response regulation, inhibition of apoptosis, and promotion of angiogenesis. These findings provide theoretical guidance for improving the quality of basic research and clinical translation.

Effects of stem cell therapy on preclinical stroke

Stroke, particularly ischemic stroke, is a leading cause of global mortality and disability. It is caused by blood flow obstruction and reduced oxygen delivery to brain tissue. Conventional treatments, such as tissue plasminogen activator (tPA) and mechanical thrombectomy (MT), have limited efficacy in repairing neural damage and carry risks of adverse effects. As a result, stem cell therapies, including mesenchymal stem cells (MSCs), have emerged as promising approaches for enhancing neural recovery and offering neuroprotection in ischemic stroke management. MSCs offer multifaceted benefits, such as reducing inflammation, protecting neurons, and promoting angiogenesis and neurogenesis. Recent evidence highlights the importance of MSC secretomes-extracellular vesicles (EVs) and exosomes rich in neuroprotective factors, such as microRNAs, proteins, and cytokines. These bioactive molecules demonstrated considerable efficacy in preclinical models by reducing neuroinflammation, preserving neurovascular integrity, and promoting cellular repair in ischemic environments. Preclinical in vitro and in vivo studies demonstrate the potential of the MSC secretomes to restore brain function after ischemic stroke. This is achieved by enhancing neuronal survival through mechanisms such as angiogenesis or vascular recovery, neuroprotection including modulation of immune or inflammatory responses, apoptosis, and autophagy, and promoting post-stroke neurogenesis. This review explores the translational challenges and future potential of integrating conventional ischemic stroke therapies with stem cell-based or cell-free approaches. The present study synthesizes current insights into the role of MSC-derived secretomes from both in vitro and in vivo studies.

Wharton's jelly of the umbilical cord serves as a natural biomaterial to promote osteogenesis

Various factors can contribute to bone damage or loss, presenting challenges for bone regeneration. Our study explores the potential clinical applications of two processed forms of Wharton's jelly of the human umbilical cord for treating bone loss. Wharton's jelly from fresh umbilical cords underwent two distinct processes: (1) frozen Wharton's jelly (WJF), preserved with cryoprotective agents, and (2) decellularized Wharton's jelly matrix (WJD), prepared only via lyophilization without cryoprotectants. Both WJD and WJF are rich in collagen, hyaluronan, and polysaccharide proteins. Notably, WJD exhibited a porous structure lacking nuclei from human umbilical cord mesenchymal stem cells, unlike WJF. In direct contact experiments, WJD stimulated osteoblast migration, enhanced osteoblast maturation, and promoted calcium deposition for bone formation when administered to cultured rat osteoblasts. Furthermore, in transwell co-culture experiments, both WJD and WJF increased the rat osteoblast expression of RUNX2 and OPN genes, elevated alkaline phosphatase levels, and enhanced extracellular calcium precipitation, indicating their role in osteoblast maturation and new bone formation. Hyaluronic acid, one of the ingredients from WJD and WJF, was identified as a key component triggering osteogenesis. In vivo experiments involved creating circular bone defects in the calvarias of rats, where WJD and WJF were separately implanted and monitored over five months using micro-computerized tomography. Our results demonstrated that both WJD and WJF enhanced angiogenesis, collagen formation, osteoblast maturation, and bone growth within the bone defects. In summary, WJD and WJF, natural biomaterials with biocompatibility and nontoxicity, act not only as effective scaffolds but also promote osteoblast adhesion and differentiation, and accelerate osteogenesis.

Priming and Combined Strategies for the Application of Mesenchymal Stem Cells in Ischemic Stroke: A Promising Approach

Ischemic stroke (IS) is a leading cause of death and disability worldwide. Tissue plasminogen activator (tPA) administration and mechanical thrombectomy are the main treatments but have a narrow time window. Mesenchymal stem cells (MSCs), which are easily scalable in vitro and lack ethical concerns, possess the potential to differentiate into various types of cells and secrete a great number of growth factors for neuroprotection and regeneration. Moreover, MSCs have low immunogenicity and tumorigenic properties, showing safety and preliminary efficacy both in preclinical studies and clinical trials of IS. However, it is unlikely that MSC treatment alone will be sufficient to maximize recovery due to the low survival rate of transplanted cells and various mechanisms of ischemic brain damage in the different stages of IS. Preconditioning was used to facilitate the homing, survival, and secretion ability of the grafted MSCs in the ischemic region, while combination therapies are alternatives that can maximize the treatment effects, focusing on multiple therapeutic targets to promote stroke recovery. In this case, the combination therapy can yield a synergistic effect. In this review, we summarize the type of MSCs, preconditioning methods, and combined strategies as well as their therapeutic mechanism in the treatment of IS to accelerate the transformation from basic research to clinical application.

Mesenchymal stem cells and their extracellular vesicles as emerging therapeutic tools in the treatment of ischemic stroke

Ischemic stroke (IS) is a neurological condition characterized by severe long-term consequences and an unfavorable prognosis for numerous patients. Despite advancements in stroke treatment, existing therapeutic approaches possess certain limitations. However, accumulating evidence suggests that mesenchymal stem/stromal cells (MSCs) hold promise as a potential therapy for various neurological disorders, including IS, owing to their advantageous properties, such as immunomodulation and tissue regeneration. Additionally, MSCs primarily exert their therapeutic effects through the release of extracellular vesicles (EVs), highlighting the significance of their paracrine activities. These EVs are small double-layered phospholipid membrane vesicles, carrying a diverse cargo of proteins, lipids, and miRNAs that enable effective cell-to-cell communication. Notably, EVs have emerged as attractive substitutes for stem cell therapy due to their reduced immunogenicity, lower tumorigenic potential, and ease of administration and handling. Hence, this review summarizes the current preclinical and clinical studies performed to investigate the safety and therapeutic potential of MSCs and their EVs derived from different sources, including bone marrow, adipose tissue, umbilical cord blood, and Wharton's jelly in IS.

Brain-derived endothelial cells are neuroprotective in a chronic cerebral hypoperfusion mouse model

Whether organ-specific regeneration is induced by organ-specific endothelial cells (ECs) remains unelucidated. The formation of white matter lesions due to chronic cerebral hypoperfusion causes cognitive decline, depression, motor dysfunction, and even acute ischemic stroke. Vascular ECs are an important target for treating chronic cerebral hypoperfusion. Brain-derived ECs transplanted into a mouse chronic cerebral hypoperfusion model showed excellent angiogenic potential. They were also associated with reducing both white matter lesions and brain dysfunction possibly due to the high expression of neuroprotective humoral factors. The in vitro coculture of brain cells with ECs from several diverse organs suggested the function of brain-derived endothelium is affected within a brain environment due to netrin-1 and Unc 5B systems. We found brain CD157-positive ECs were more proliferative and beneficial in a mouse model of chronic cerebral hypoperfusion than CD157-negative ECs upon inoculation. We propose novel methods to improve the symptoms of chronic cerebral hypoperfusion using CD157-positive ECs.

Exosomes derived from human umbilical cord mesenchymal stem cells pretreated by monosialoteterahexosyl ganglioside alleviate intracerebral hemorrhage by down-regulating autophagy

PURPOSE

Intracerebral hemorrhage (ICH) results in substantial morbidity, mortality, and disability. Depleting neural cells in advanced stages of ICH poses a significant challenge to recovery. The objective of our research is to investigate the potential advantages and underlying mechanism of exosomes obtained from human umbilical cord mesenchymal stem cells (hUMSCs) pretreated with monosialoteterahexosyl ganglioside (GM1) in the prevention of secondary brain injury (SBI) resulting from ICH.

PATIENTS AND METHODS

In vitro, hUMSCs were cultured and induced to differentiate into neuron-like cells after they were pretreated with 150 μg/mL GM1. The exosomes extracted from the culture medium following a 6-h pretreatment with 150 μg/mL GM1 were used as the treatment group. Striatal infusion of collagenase and hemoglobin (Hemin) was used to establish in vivo and in vitro models of ICH.

RESULTS

After being exposed to 150 μg/mL GM1 for 6 h, specific cells displayed typical neuron-like cell morphology and expressed neuron-specific enolase (NSE). The rate of differentiation into neuron-like cells was up to (15.9 ± 5.8) %, and the synthesis of N-Acetylgalactosaminyltransferase (GalNAcT), which is upstream of GM1, was detected by Western blot. This study presented an increase in the synthesis of GalNAcT. Compared with the ICH group, apoptosis in the treatment group was remarkably reduced, as detected by TUNEL, and mitochondrial membrane potential was restored by JC-1. Additionally, Western blot revealed the restoration of up-regulated autophagy markers Beclin-1 and LC3 and the down-regulation of autophagy marker p62 after ICH.

CONCLUSION

These findings suggest that GM1 is an effective agent to induce the differentiation of hUMSCs into neuron-like cells. GM1 can potentially increase GalNAcT production through "positive feedback", which generates more GM1 and promotes the differentiation of hUMSCs. After pretreatment with GM1, exosomes derived from hUMSCs (hUMSCs-Exos) demonstrate a neuroprotective effect by inhibiting autophagy in the ICH model. This study reveals the potential mechanism by which GM1 induces differentiation of hUMSCs into neuron-like cells and confirms the therapeutic effect of hUMSCs-Exos pretreated by GM1 (GM1-Exos) on an ICH model, potentially offering a new direction for stem cell therapy in ICH.

Therapeutic potential of mesenchymal stem cells for cerebral small vessel disease

Cerebral small vessel disease (CSVD), as the most common, chronic and progressive vascular disease on the brain, is a serious neurological disease, whose pathogenesis remains unclear. The disease is a leading cause of stroke and vascular cognitive impairment and dementia, and contributes to about 20% of strokes, including 25% of ischemic strokes and 45% of dementias. Undoubtedly, the high incidence and poor prognosis of CSVD have brought a heavy economic and medical burden to society. The present treatment of CSVD focuses on the management of vascular risk factors. Although vascular risk factors may be important causes or accelerators of CSVD and should always be treated in accordance with best clinical practice, controlling risk factors alone could not curb the progression of CSVD brain injury. Therefore, developing safer and more effective treatment strategies for CSVD is urgently needed. Recently, mesenchymal stem cells (MSCs) therapy has become an emerging therapeutic modality for the treatment of central nervous system disease, given their paracrine properties and immunoregulatory. Herein, we discussed the therapeutic potential of MSCs for CSVD, aiming to enable clinicians and researchers to understand of recent progress and future directions in the field.

Neural Correlates and Molecular Mechanisms of Memory and Learning

Memory and learning are essential cognitive processes that enable us to obtain, retain, and recall information [...].

Emerging Translational Research in Neurological and Psychiatric Diseases: From In Vitro to In Vivo Models

Revealing the underlying pathomechanisms of neurological and psychiatric disorders, searching for new biomarkers, and developing novel therapeutics all require translational research [...].

Reversal of Pulmonary Fibrosis: Human Umbilical Mesenchymal Stem Cells from Wharton's Jelly versus Human-Adipose-Derived Mesenchymal Stem Cells

Pulmonary fibrosis (PF) is a progressive, non-reversible illness with various etiologies. Currently, effective treatments for fibrotic lungs are still lacking. Here, we compared the effectiveness of transplantation of human mesenchymal stem cells from umbilical cord Wharton's jelly (HUMSCs) versus those from adipose tissue (ADMSCs) in reversing pulmonary fibrosis in rats. Bleomycin 5 mg was intratracheally injected to establish a severe, stable, single left lung animal model with PF. On Day 21 post-BLM administration, one single transplantation of 2.5 × 10⁷ HUMSCs or ADMSCs was performed. Lung function examination of Injury and Injury+ADMSCs rats displayed significantly decreased blood oxygen saturation and increased respiratory rates, while Injury+HUMSCs rats showed statistical amelioration in blood oxygen saturation and significant alleviation in respiratory rates. Reduced cell number in the bronchoalveolar lavage and lower myofibroblast activation appeared in the rats transplanted with either ADMSCs or HUMSCS than that in the Injury group. However, ADMSC transplantation stimulated more adipogenesis. Furthermore, matrix-metallopeptidase-9 over-expression for collagen degradation, and the elevation of Toll-like receptor-4 expression for alveolar regeneration were observed only in the Injury+HUMSCs. In comparison with the transplantation of ADMSCs, transplantation of HUMSCs exhibited a much more effective therapeutic effect on PF, with significantly better results in alveolar volume and lung function.

Pre-clinical efficacy evaluation of human umbilical cord mesenchymal stem cells for ischemic stroke

Objective

This study explored the underlying therapeutic mechanism of human umbilical cord mesenchymal stem cells (hUCMSCs) for ischemic stroke (IS), and determined the optimal administration time windows and dose-effect relationship.

Methods

The levels of SDF-1α, IL-10, IL-6, TNF-α, BDNF, IL-1β, and VEGF-A factors in serum and brain tissue lysate were measured by ELISA. The pathological status of brain tissues was evaluated by Hematoxylin-Eosin (HE) staining, and apoptosis of nerve cells was detected by tunel. The protein expression of CXCR-4, NeuN, and Nestin in the brain tissues was assessed through immunofluorescence. The balance beam, forelimb muscle strength, and limb placement were tested on MCAO rats at different time points and doses. The infarct area of the rat brain tissues was measured at the end of the experiment.

Results

The hUCMSC treatment during the acute phase of MCAO significantly reduced the secretion of IL-6, TNF-α, IL-1β but increased IL-10 in serum, and the levels of SDF-α and BDNF in serum and brain tissues lysate were also increased. The pathological results showed that there were more neurons in the treatment group compared to the model group. Immunofluorescence assays showed that the expression of CXCR4、Nestin、NeuN was relatively higher than that in the model group. The d4 and d7 treatment significantly improves the motor function, promotes the recovery of forelimb muscle strength, increases the forelimb placement rate and reduces the scope of cerebral infarction, but the d14 treatment group has less therapeutic effect compared to the d4 and d7 treatment. The 2×10⁷/kg treatment showed the best therapeutic effect, followed by the 1×10⁷/kg treatment, and the worst is 0.5×10⁷/kg treatment from the test of balance beam, forelimb muscle strength, limb placement and the infarct area of the rat brain tissues.

Conclusion

The hUCMSCs can inhibit the infiltration of inflammatory cells in the brain tissue, and promote the repair of brain tissue structure and function. Early intervention by injecting high-dose of hUCMSCs can significantly improve the recovery of neurological/motor function and reduce the size of cerebral infarction in rats.

Stem Cells Attenuate the Inflammation Crosstalk Between Ischemic Stroke and Multiple Sclerosis: A Review

The immense neuroinflammation induced by multiple sclerosis (MS) promotes a favorable environment for ischemic stroke (IS) development, making IS a deadly complication of MS. The overlapping inflammation in MS and IS is a prelude to the vascular pathology, and an inherent cell death mechanism that exacerbates neurovascular unit (NVU) impairment in the disease progression. Despite this consequence, no therapies focus on reducing IS incidence in patients with MS. To this end, the preclinical and clinical evidence we review here argues for cell-based regenerative medicine that will augment the NVU dysfunction and inflammation to ameliorate IS risk.

Modelling the neurodevelopmental pathogenesis in neuropsychiatric disorders. Bioactive kynurenines and their analogues as neuroprotective agents-in celebration of 80th birthday of Professor Peter Riederer

Following introduction of the monoamine oxidase type B inhibitor selegiline for the treatment of Parkinson's disease (PD), discovery of the action mechanism of Alzheimer's disease-modifying agent memantine, the role of iron in PD, and the loss of electron transport chain complex I in PD, and development of the concept of clinical neuroprotection, Peter Riederer launched one of the most challenging research project neurodevelopmental aspects of neuropsychiatric disorders. The neurodevelopmental theory holds that a disruption of normal brain development in utero or during early life underlies the subsequent emergence of neuropsychiatric symptoms during later life. Indeed, the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition and the International Classification of Diseases, 11th Revision categorize autism spectrum disorder and attention deficit hyperactivity disorder in neurodevelopmental disorders (NDDs). More and more evidence, especially from preclinical studies, is revealing that neurodevelopmental pathology is not limited to the diagnostic class above, but also contributes to the development of other psychiatric disorders such as schizophrenia, bipolar disorder, and obsessive-compulsive disorder as well as neurodegenerative diseases such as PD and Huntington's disease. Preclinical animal research is taking a lead in understanding the pathomechanisms of NDDs, searching for novel targets, and developing new neuroprotective agents against NDDs. This narrative review discusses emerging evidence of the neurodevelopmental etiology of neuropsychiatric disorders, recent advances in modelling neurodevelopmental pathogenesis, potential strategies of clinical neuroprotection using novel kynurenine metabolites and analogues, and future research direction for NDDs.