Therapeutic effect of human umbilical cord mesenchymal stem cells on neonatal rat hypoxic-ischemic encephalopathy

Mesenchymal stem cell therapy in perinatal arterial ischemic stroke: systematic review of preclinical studies

BACKGROUND

Perinatal arterial ischemic stroke (PAIS) is a neurologic disorder leading to long-term complications. Mesenchymal stem cells (MSCs) have emerged as a novel therapeutic agent. This systematic review aims to determine the effects of stem cell-based interventions for the treatment of PAIS in preclinical studies.

METHODS

We included all controlled studies on MSCs in neonatal animals with PAIS. Functional outcome was the primary outcome. The literature search was performed in February 2021.

RESULTS

In the 20 included studies, MSCs were most frequently delivered via intracerebral injection (n = 9), 3 days after the induction of PAIS (n = 8), at a dose ranging from 5 × 104 to 5 × 106 cells. The meta-analysis showed an improvement on the cylinder rearing test (MD: -10.62; 95% CI: -14.38 to -6.86) and on the water maze test (MD: 1.31 MD; 95% CI: 0.80 to 1.81) in animals treated with MSCs compared to the control group animals.

CONCLUSION

MSCs appear to improve sensorimotor and cognitive performance in PAIS-injured animals; however, the certainty of the evidence is low. Registration of the protocol of preclinical studies, appropriate sample size calculation, rigorous randomization, and reporting of the data on animal sex and survival are warranted. PROSPERO registration number: CRD42021239642.

IMPACT

This is the first systematic review and meta-analysis of preclinical studies investigating the effects of MSCs in an experimental model of PAIS. MSCs appear to improve sensorimotor and cognitive performance in PAIS-injured neonatal animals. The certainty of the evidence is low due to high or unclear risk of bias in most domains.

A Pilot Phase I Trial of Allogeneic Umbilical Cord Tissue-Derived Mesenchymal Stromal Cells in Neonates With Hypoxic-Ischemic Encephalopathy

Hypoxic ischemic encephalopathy (HIE) in neonates causes increased mortality and long-term morbidity in surviving babies. Hypothermia (HT) has improved outcomes, however, mortality remains high with ~half of surviving babies developing neurological impairment in their first years. We previously explored the use of autologous cord blood (CB) to determine if CB cells could lessen long-term damage to the brain. However, the feasibility of CB collection from sick neonates limited the utility of this approach. Allogeneic cord tissue mesenchymal stromal cells (hCT-MSC), cryopreserved and readily available, have been shown to ameliorate brain injury in animal models of HIE. We, therefore, conducted a pilot, phase I, clinical trial to test the safety and describe the preliminary efficacy of hCT-MSC in neonates with HIE. The study treated infants with moderate to severe HIE, treated with HT, with 1 or 2 doses of 2 million cells/kg/dose of hCT-MSC given intravenously. The babies were randomized to receive 1 or 2 doses with the first dose during HT and the second dose 2 months later. Babies were followed for survival and development with scoring of Bayley's at 12 postnatal months. Six neonates with moderate (4) or severe (2) HIE were enrolled. All received 1 dose of hCT-MSC during HT and 2 received a 2nd dose, 2 months later. hCT-MSC infusions were well tolerated although 5/6 babies developed low titer anti-HLA antibodies by 1 year of age. All babies survived, with average to low-average developmental assessment standard scores for ages between 12 and 17 postnatal months. Further study is warranted.

Barriers in translating stem cell therapies for neonatal diseases

Over the last 20 years, stem cells of varying origin and their associated secretome have been investigated as a therapeutic option for a myriad of neonatal models of disease, with very promising results. Despite the devastating nature of some of these disorders, translation of the preclinical evidence to the bedside has been slow. In this review, we explore the existing clinical evidence for stem cell therapies in neonates, highlight the barriers faced by researchers and suggest potential solutions to move the field forward.

Nonhematopoietic Umbilical Cord Blood Stem Cell Administration Improves Long-term Neurodevelopment After Periventricular-Intraventricular Hemorrhage in Neonatal Rats

Periventricular-intraventricular hemorrhage (PIVH) is common in extremely low gestational age neonates (ELGAN) and leads to motor and behavioral impairments. Currently there is no effective treatment for PIVH. Whether human nonhematopoietic umbilical cord blood-derived stem cell (nh-UCBSC) administration reduces the severity of brain injury and improves long-term motor and behavioral function was tested in an ELGAN-equivalent neonatal rat model of PIVH. In a collagenase-induced unilateral PIVH on postnatal day (P) 2 model, rat pups received a single dose of nh-UCBSCs at a dose of 1 × 106 cells i.p. on P6 (PIVH + UCBSC group) or were left untreated (Untreated PIVH group). Motor deficit was determined using forelimb placement, edge-push, and elevated body swing tests at 2 months (N = 5-8). Behavior was evaluated using open field exploration and rearing tests at 4 months (N =10-12). Cavity volume and hemispheric volume loss on the PIVH side were determined at 7 months (N = 6-7). Outcomes were compared between the Untreated PIVH and PIVH + UCBSC groups and a Control group. Unilateral motor deficits were present in 60%-100% of rats in the Untreated PIVH group and 12.5% rats in the PIVH + UCBSC group (P = 0.02). Untreated PIVH group exhibited a higher number of quadrant crossings in open field exploration, indicating low emotionality and poor habituation, and had a cavitary lesion and hemispheric volume loss on the PIVH side. Performance in open field exploration correlated with cavity volume (r2 = 0.25; P < 0.05). Compared with the Untreated PIVH group, performance in open field exploration was better (P = 0.0025) and hemispheric volume loss was lower (19.9 ± 4.4% vs 6.1 ± 2.6%, P = 0.018) in the PIVH + UCBSC group. These results suggest that a single dose of nh-UCBSCs administered in the subacute period after PIVH reduces the severity of injury and improves neurodevelopment in neonatal rats.

Rationale for the Use of Cord Blood in Hypoxic-Ischaemic Encephalopathy

Hypoxic-ischaemic encephalopathy (HIE) is a severe complication of asphyxia at birth. Therapeutic hypothermia, the standard method for HIE prevention, is effective in only 50% of the cases. As the understanding of the immunological basis of these changes increases, experiments have begun with the use of cord blood (CB) because of its neuroprotective properties. Mechanisms for the neuroprotective effects of CB stem cells include antiapoptotic and anti-inflammatory actions, stimulation of angiogenesis, production of trophic factors, and mitochondrial donation. In several animal models of HIE, CB decreased oxidative stress, cell death markers, CD4+ T cell infiltration, and microglial activation; restored normal brain metabolic activity; promoted neurogenesis; improved myelination; and increased the proportion of mature oligodendrocytes, neuron numbers in the motor cortex and somatosensory cortex, and brain weight. These observations translate into motor strength, limb function, gait, and cognitive function and behaviour. In humans, the efficacy and safety of CB administration were reported in a few early clinical studies which confirmed the feasibility and safety of this intervention for up to 10 years. The results of these studies showed an improvement in the developmental outcomes over hypothermia. Two phase-2 clinical studies are ongoing under the United States regulations, namely one controlled study and one blinded study.

Umbilical cord blood therapy modulates neonatal hypoxic ischemic brain injury in both females and males

Preclinical and clinical studies have shown that sex is a significant risk factor for perinatal morbidity and mortality, with males being more susceptible to neonatal hypoxic ischemic (HI) brain injury. No study has investigated sexual dimorphism in the efficacy of umbilical cord blood (UCB) cell therapy. HI injury was induced in postnatal day 10 (PND10) rat pups using the Rice-Vannucci method of carotid artery ligation. Pups received 3 doses of UCB cells (PND11, 13, 20) and underwent behavioural testing. On PND50, brains were collected for immunohistochemical analysis. Behavioural and neuropathological outcomes were assessed for sex differences. HI brain injury resulted in a significant decrease in brain weight and increase in tissue loss in females and males. Females and males also exhibited significant cell death, region-specific neuron loss and long-term behavioural deficits. Females had significantly smaller brains overall compared to males and males had significantly reduced neuron numbers in the cortex compared to females. UCB administration improved multiple aspects of neuropathology and functional outcomes in males and females. Females and males both exhibited injury following HI. This is the first preclinical evidence that UCB is an appropriate treatment for neonatal brain injury in both female and male neonates.

Progress in Mesenchymal Stem Cell Therapy for Ischemic Stroke

Ischemic stroke (IS) is a serious cerebrovascular disease with high morbidity and disability worldwide. Despite the great efforts that have been made, the prognosis of patients with IS remains unsatisfactory. Notably, recent studies indicated that mesenchymal stem cell (MSCs) therapy is becoming a novel research hotspot with large potential in treating multiple human diseases including IS. The current article is aimed at reviewing the progress of MSC treatment on IS. The mechanism of MSCs in the treatment of IS involved with immune regulation, neuroprotection, angiogenesis, and neural circuit reconstruction. In addition, nutritional cytokines, mitochondria, and extracellular vesicles (EVs) may be the main mediators of the therapeutic effect of MSCs. Transplantation of MSCs-derived EVs (MSCs-EVs) affords a better neuroprotective against IS when compared with transplantation of MSCs alone. MSC therapy can prolong the treatment time window of ischemic stroke, and early administration within 7 days after stroke may be the best treatment opportunity. The deliver routine consists of intraventricular, intravascular, intranasal, and intraperitoneal. Furthermore, several methods such as hypoxic preconditioning and gene technology could increase the homing and survival ability of MSCs after transplantation. In addition, MSCs combined with some drugs or physical therapy measures also show better neurological improvement. These data supported the notion that MSC therapy might be a promising therapeutic strategy for IS. And the application of new technology will promote MSC therapy of IS.

Stem Cell Therapy for Neonatal Hypoxic-Ischemic Encephalopathy: A Systematic Review of Preclinical Studies

Neonatal hypoxic-ischemic encephalopathy (HIE) is an important cause of mortality and morbidity in the perinatal period. This condition results from a period of ischemia and hypoxia to the brain of neonates, leading to several disorders that profoundly affect the daily life of patients and their families. Currently, therapeutic hypothermia (TH) is the standard of care in developing countries; however, TH is not always effective, especially in severe cases of HIE. Addressing this concern, several preclinical studies assessed the potential of stem cell therapy (SCT) for HIE. With this systematic review, we gathered information included in 58 preclinical studies from the last decade, focusing on the ones using stem cells isolated from the umbilical cord blood, umbilical cord tissue, placenta, and bone marrow. Outstandingly, about 80% of these studies reported a significant improvement of cognitive and/or sensorimotor function, as well as decreased brain damage. These results show the potential of SCT for HIE and the possibility of this therapy, in combination with TH, becoming the next therapeutic approach for HIE. Nonetheless, few preclinical studies assessed the combination of TH and SCT for HIE, and the existent studies show some contradictory results, revealing the need to further explore this line of research.

Transfer of lncRNA UCA1 by hUCMSCs-derived exosomes protects against hypoxia/reoxygenation injury through impairing miR-143-targeted degradation of Bcl-2

Ischemia results in neuronal damage via alterations in gene transcription and protein expression. Long noncoding RNAs (LncRNAs) are pivotal in the regulation of target protein expression in hypoxia/reoxygenation (H/R). In this study, we observed the function of exosomes-carried lncRNA UCA1 in H/R-induced injury of cardiac microvascular endothelial cells (CMECs). In H/R cell model, CMECs were co-cultured with human umbilical cord mesenchymal stem cell-derived exosomes (hUCMSC-ex). The loss-of-function experiments were conducted to assess the effect of lncRNA UCA1 on H/R injury by assessing the biological behaviors of CMECs. The relationship among lncRNA UCA1, miR-143 and Bcl-2 were verified. An ischemia-reperfusion (I/R) rat model was established. Then hUCMSC-ex was injected into I/R rats to identify its effects on apoptosis and autophagy. Functional rescue experiments were performed to verify the sponge system. In vitro and in vivo experiments showed that hUCMSC-ex protected I/R rats and H/R CMECs against injury. Silencing UCA1 in hUCMSC-ex or miR-143 overexpression aggravated H/R injury in CMECs. LncRNA UCA1 competitively bound to miR-143 to upregulate Bcl-2. And hUCMSCs-ex/si-UCA1+inhi-miR-143 treatment protected CMECs against H/R injury and inhibited hyperautophagy. Together, hUCMSC-ex-derived lncRNA UCA1 alleviates H/R injury through the miR-143/Bcl-2/Beclin-1 axis. Hence, this study highlights a stem cell-based approach against I/R injury.

Therapeutic potential of stem cells for preterm infant brain damage: Can we move from the heterogeneity of preclinical and clinical studies to established therapeutics?

Acquired perinatal brain injuries are a set of conditions that remains a key challenge for neonatologists and that have significant social, emotional and financial implications for our communities. In our perspective article, we will introduce perinatal brain injury focusing specifically on the events leading to brain damage in preterm born infants and outcomes for these infants. Then we will summarize and discuss the preclinical and clinical studies testing the efficacy of stem cells as neuroprotectants in the last ten years in perinatal brain injury. There are no therapies to treat brain damage in preterm born infants and a primary finding from this review is that there is a scarcity of stem cell trials focused on overcoming brain injuries in these infants. Overall, across all forms of perinatal brain injury there is a remarkable heterogeneity in previous and on-going preclinical and clinical studies in terms of the stem cell type, animal models/patient selection, route and time of administration. Despite the quality of many of the studies this variation makes it difficult to reach a valid consensus for future developments. However, it is clear that stem cells (and stem cell derived exosomes) can reduce perinatal brain injury and our field needs to work collectively to refine an effective protocol for each type of injury. The use of standardized stem cell products and testing these products across multiple models of injury will provide a stronger framework for clinical trials development.

Narrative review of stem cell therapy for ischemic brain injury

Ischemic brain injury is a common cause of long-term neurological deficits in children as well as adults, and no efficient treatments could reverse the sequelae in clinic till now. Stem cells have the capacity of self-renewal and multilineage differentiation. The therapeutic efficacy of stem cell transplantation for ischemic brain injury have been tested for many years. The grafts could survive and mature in the ischemic brain environment. Stem cell transplantation could improve functional recovery of ischemic brain injury models in pre-clinical trials. The potential mechanisms included cell replacement, release of neurotrophic and anti-inflammatory factors, immunoregulation as well as activation of endogenous neurogenesis. Besides, many clinical trials were conducted and some of trials already had preliminary results. From the current published data, cell transplantation for clinical application is safe and feasible. No severe adverse events and tumorigenesis were reported. While the therapeutic efficacy of stem cell therapy in clinic still needs more evidences. In this review, we overviewed the studies about stem cell therapy for ischemic brain injury. Different types of stem cells used for transplantation as well as the therapeutic mechanisms were discussed in detail. The related pre-clinical and clinical trials were summarized into two separate tables. In addition, we also discussed the unsolved problems and concerns about stem cell therapy for ischemic brain injury that need to be overcome before clinic transformation.

Bone marrow mesenchymal stem cells overexpressing hepatocyte growth factor ameliorate hypoxic-ischemic brain damage in neonatal rats

Objectives

Hypoxic–ischemic brain damage (HIBD) is a major cause of brain injury in neonates. Bone marrow mesenchymal stem cells (BMSCs) show therapeutic potential for HIBD, and genetic modification may enhance their neuroprotective effects. The goal of this study was to investigate the neuroprotective effects of hepatocyte growth factor (HGF)-overexpressing BMSCs (BMSCs-HGF) against HIBD and their underlying mechanisms.

Methods:

BMSCs were transfected with HGF using adenoviral vectors. HIBD models were established and then BMSCs were transplanted into the brains of HIBD rats via intraventricular injection. 2,3,5-Triphenyltetrazolium chloride (TTC) staining was used to measure cerebral infarction volumes. In vitro, primary cultured cortical neurons were co-cultured with BMSCs in a Transwell plate system. Oxygen–glucose deprivation (OGD) was applied to imitate hypoxic–ischemic insult, and PD98059 was added to the culture medium to block the phosphorylation of extracellular signal-regulated kinase (ERK). Cell apoptosis was determined using TUNEL staining. The expression of HGF was measured by immunofluorescence, real-time quantitative PCR (RT-qPCR), and western blots. The expression of phosphorylated ERK (p-ERK) and B-cell lymphoma-2 (Bcl-2) was measured by western blots.

Results

HGF-gene transfection promoted BMSC proliferation. Moreover, BMSCs-HGF decreased HIBD-induced cerebral infarction volumes and enhanced the protective effects of the BMSCs against HIBD. BMSCs-HGF also increased expression of HGF, p-ERK, and Bcl-2 in brain tissues. In vitro, BMSC-HGF protected neurons against OGD-induced apoptosis. Inhibition of ERK phosphorylation abolished the neuroprotective effect of BMSCs-HGF against OGD.

Conclusions

BMSCs-HGF is a potential treatment for HIBD and that the ERK/Bcl-2 pathway is involved in the underlying neuroprotective mechanism.

Mesenchymal stem cells as a multimodal treatment for nervous system diseases

Neurological disorders are a massive challenge for modern medicine. Apart from the fact that this group of diseases is the second leading cause of death worldwide, the majority of patients have no access to any possible effective and standardized treatment after being diagnosed, leaving them and their families helpless. This is the reason why such great emphasis is being placed on the development of new, more effective methods to treat neurological patients. Regenerative medicine opens new therapeutic approaches in neurology, including the use of cell-based therapies. In this review, we focus on summarizing one of the cell sources that can be applied as a multimodal treatment tool to overcome the complex issue of neurodegeneration-mesenchymal stem cells (MSCs). Apart from the highly proven safety of this approach, beneficial effects connected to this type of treatment have been observed. This review presents modes of action of MSCs, explained on the basis of data from vast in vitro and preclinical studies, and we summarize the effects of using these cells in clinical trial settings. Finally, we stress what improvements have already been made to clarify the exact mechanism of MSCs action, and we discuss potential ways to improve the introduction of MSC-based therapies in clinics. In summary, we propose that more insightful and methodical optimization, by combining careful preparation and administration, can enable use of multimodal MSCs as an effective, tailored cell therapy suited to specific neurological disorders.

Optimizing Stem Cell Therapy after Ischemic Brain Injury

Stem cells have been used for regenerative and therapeutic purposes in a variety of diseases. In ischemic brain injury, preclinical studies have been promising, but have failed to translate results to clinical trials. We aimed to explore the application of stem cells after ischemic brain injury by focusing on topics such as delivery routes, regeneration efficacy, adverse effects, and in vivo potential optimization. PUBMED and Web of Science were searched for the latest studies examining stem cell therapy applications in ischemic brain injury, particularly after stroke or cardiac arrest, with a focus on studies addressing delivery optimization, stem cell type comparison, or translational aspects. Other studies providing further understanding or potential contributions to ischemic brain injury treatment were also included. Multiple stem cell types have been investigated in ischemic brain injury treatment, with a strong literature base in the treatment of stroke. Studies have suggested that stem cell administration after ischemic brain injury exerts paracrine effects via growth factor release, blood-brain barrier integrity protection, and allows for exosome release for ischemic injury mitigation. To date, limited studies have investigated these therapeutic mechanisms in the setting of cardiac arrest or therapeutic hypothermia. Several delivery modalities are available, each with limitations regarding invasiveness and safety outcomes. Intranasal delivery presents a potentially improved mechanism, and hypoxic conditioning offers a potential stem cell therapy optimization strategy for ischemic brain injury. The use of stem cells to treat ischemic brain injury in clinical trials is in its early phase; however, increasing preclinical evidence suggests that stem cells can contribute to the down-regulation of inflammatory phenotypes and regeneration following injury. The safety and the tolerability profile of stem cells have been confirmed, and their potent therapeutic effects make them powerful therapeutic agents for ischemic brain injury patients.

Intranasal administration of Cytoglobin modifies human umbilical cord‑derived mesenchymal stem cells and improves hypoxic‑ischemia brain damage in neonatal rats by modulating p38 MAPK signaling‑mediated apoptosis

Neonatal hypoxic‑ischemic brain damage (HIBD) is a common clinical syndrome in newborns. Hypothermia is the only approved therapy for the clinical treatment; however, the therapeutic window of hypothermia is confined to 6 h after birth and even then, >40% of the infants either die or survive with various impairments, including cerebral palsy, seizure disorder and intellectual disability following hypothermic treatment. The aim of the present study was to determine whether nasal transplantation of Cytoglobin (CYGB) genetically modified human umbilical cord‑derived mesenchymal stem cells (CYGB‑HuMSCs) exhibited protective effects in neonatal rats with HIBD compared with those treated without genetically modified CYGB. A total of 120 neonatal Sprague‑Dawley rats (postnatal day 7) were assigned to either a Sham, HIBD, HuMSCs or CYGB‑HuMSCs group (n = 30 rats/group). For HIBD modeling, rats underwent left carotid artery ligation and were exposed to 8% oxygen for 2.5 h. A total of 30 min after HI, HuMSCs (or CYGB‑HuMSCs) labeled with enhanced‑green fluorescent protein (eGFP) were intranasally administered. After modeling for 3, 14 and 29 days, five randomly selected rats were sacrificed in each group, and the expression levels of CYGB, ERK, JNK and p38 in brain tissues were determined. Nissl staining of the cortex and hippocampal Cornu Ammonis 1 area of rats in each group were compared after 3 days of modeling. TUNEL assay and immunofluorescence were performed 3 days after modeling. Long term memory in rats was assessed using a Morris‑water maze 29 days after modeling. The HIBD group demonstrated significant deficiencies compared with the Sham group based on Nissl staining, TUNEL assay and the Morris‑water maze test. HuMSC treated rats exhibited improvement on in all the tests, and CYGB‑HuMSCs treatment resulted in further improvements. PCR and western blotting results indicated that the CYGB mRNA and protein levels were increased from day 3 to day 29 after transplantation of CYGB‑HuMSCs. Furthermore, it was identified that CYGB‑HuMSC transplantation suppressed p38 signaling at all experimental time points. Immunofluorescence indicated the scattered presence of HuMSCs or CYGB‑HuMSCs in damaged brain tissue. No eGFP and glial fibrillary acidic protein or eGFP and neuron‑specific enolase double‑stained positive cells were found in the brain tissues. Therefore, CYGB‑HuMSCs may serve as a gene transporter, as well as exert a neuroprotective and antiapoptotic effect in HIBD, potentially via the p38 mitogen‑activated protein kinase signaling pathway.

Multiple doses of umbilical cord blood cells improve long-term brain injury in the neonatal rat

BACKGROUND

Hypoxic ischemic (HI) insults during pregnancy and birth can result in neurodevelopmental disorders, such as cerebral palsy. We have previously shown that a single dose of umbilical cord blood (UCB) cells is effective at reducing short-term neuroinflammation and improves short and long-term behavioural outcomes in rat pups. A single dose of UCB was not able to modulate long-term neuroinflammation or brain tissue loss. In this study we examined whether multiple doses of UCB can modulate neuroinflammation, decrease cerebral tissue damage and improve behavioural outcomes when followed up long-term.

METHODS

HI injury was induced in postnatal day 10 (PND10) rat pups using the Rice-Vannucci method of carotid artery ligation. Pups received either 1 dose (PND11), or 3 doses (PND11, 13, 20) of UCB cells. Rats were followed with behavioural testing, to assess both motor and cognitive outcomes. On PND50, brains were collected for analysis.

RESULTS

HI brain injury in rat pups caused significant behavioural deficits. These deficits were significantly improved by multiple doses of UCB. HI injury resulted in a significant decrease in brain weight and left hemisphere tissue, which was improved by multiple doses of UCB. HI resulted in increased cerebral apoptosis, loss of neurons and upregulation of activated microglia. Multiple doses of UCB modulated these neuropathologies. A single dose of UCB at PND11 did not improve behavioural or neuropathological outcomes.

CONCLUSIONS

Treatment with repeated doses of UCB is more effective than a single dose for reducing tissue damage, improving brain pathology and restoring behavioural deficits following perinatal brain injury.

Regenerative potential of Wharton's jelly-derived mesenchymal stem cells: A new horizon of stem cell therapy

Umbilical cord Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) have recently gained considerable attention in the field of regenerative medicine. Their high proliferation rate, differentiation ability into various cell lineages, easy collection procedure, immuno-privileged status, nontumorigenic properties along with minor ethical issues make them an ideal approach for tissue repair. Besides, the number of WJ-MSCs in the umbilical cord samples is high as compared to other sources. Because of these properties, WJ-MSCs have rapidly advanced into clinical trials for the treatment of a wide range of disorders. Therefore, this paper summarized the current preclinical and clinical studies performed to investigate the regenerative potential of WJ-MSCs in neural, myocardial, skin, liver, kidney, cartilage, bone, muscle, and other tissue injuries.

Human umbilical cord blood-mesenchymal stem cell-derived secretome in combination with atorvastatin enhances endothelial progenitor cells proliferation and migration

Background: Human umbilical cord blood-mesenchymal stem cell (hUCB-MSC)-derived secretome is known to be able to promote neovascularization and angiogenesis, so it is also thought to have a capability to modulate endothelial progenitor cell (EPC) functions. Atorvastatin is the cornerstone of coronary artery disease (CAD) treatment which can enhance EPCs proliferation and migration. This study aims to analyze the effect of the hUCB-MSC-derived secretome and its combination with atorvastatin toward EPCs proliferation and migration. Methods: EPCs were isolated from a CAD patient's peripheral blood. Cultured EPCs were divided into a control group and treatment group of 2.5 µM atorvastatin, hUCB-MSC-derived secretome (2%, 10%, and 20% concentration) and its combination. EPCs proliferation was evaluated using an MTT cell proliferation assay, and EPC migration was evaluated using a Transwell migration assay kit. Results: This research showed that hUCB-MSC-derived secretomes significantly increase EPC proliferation and migration in a dose-dependent manner. The high concentration of hUCB-MSC-derived secretome were shown to be superior to atorvastatin in inducing EPC proliferation and migration (p<0.001). A combination of the hUCB-MSC-derived secretome and atorvastatin shown to improve EPCs proliferation and migration compared to hUCB-MSC-derived secretome treatment or atorvastatin alone (p<0.001). Conclusions: This study concluded that the hUCB-MSC-derived secretome work synergistically with atorvastatin treatment in improving EPCs proliferation and migration.

Human umbilical cord blood-mesenchymal stem cell-derived secretome in combination with atorvastatin enhances endothelial progenitor cells proliferation and migration

Background: Human umbilical cord blood-mesenchymal stem cell (hUCB-MSC)-derived secretome is known to be able to promote neovascularization and angiogenesis, so it is also thought to have a capability to modulate endothelial progenitor cell (EPC) functions. Atorvastatin is the cornerstone of coronary artery disease (CAD) treatment which can enhance EPCs proliferation and migration. This study aims to analyze the effect of the hUCB-MSC-derived secretome and its combination with atorvastatin toward EPCs proliferation and migration. Methods: EPCs were isolated from a CAD patient's peripheral blood. Cultured EPCs were divided into a control group and treatment group of 2.5 µM atorvastatin, hUCB-MSC-derived secretome (2%, 10%, and 20% concentration) and its combination. EPCs proliferation was evaluated using an MTT cell proliferation assay, and EPC migration was evaluated using a Transwell migration assay kit. Results: This research showed that hUCB-MSC-derived secretomes significantly increase EPC proliferation and migration in a dose-dependent manner. The high concentration of hUCB-MSC-derived secretome were shown to be superior to atorvastatin in inducing EPC proliferation and migration (p<0.001). A combination of the hUCB-MSC-derived secretome and atorvastatin shown to improve EPCs proliferation and migration compared to hUCB-MSC-derived secretome treatment or atorvastatin alone (p<0.001). Conclusions: This study concluded that the hUCB-MSC-derived secretome work synergistically with atorvastatin treatment in improving EPCs proliferation and migration.

Therapeutic evidence of umbilical cord-derived mesenchymal stem cell transplantation for cerebral palsy: a randomized, controlled trial

BACKGROUND

Cerebral palsy (CP) is a syndrome of childhood movement and posture disorders. Clinical evidence is still limited and sometimes inconclusive about the benefits of human umbilical cord mesenchymal stem cells (hUC-MSCs) for CP. We conducted a randomized trial to evaluate the safety and efficacy of hUC-MSC transplantation concomitant with rehabilitation in patients with CP.

METHODS

Eligible patients were allocated into the hUC-MSC group and control group. In addition to rehabilitation, the patients in the hUC-MSC group received four transfusions of hUC-MSCs intravenously, while the control group received a placebo. Adverse events (AEs) were collected for safety evaluation in the 12-month follow-up phase. Primary endpoints were assessed as activities of daily living (ADL), comprehensive function assessment (CFA), and gross motor function measure (GMFM) scales. In addition, cerebral metabolic activity was detected by 18F-FDG-PET/CT to explore the possible mechanism of the therapeutic effects. Primary endpoint data were analyzed by ANOVA using SPSS version 20.0.

RESULTS

Forty patients were enrolled, and 1 patient withdrew informed consent. Therefore, 39 patients received treatments and completed the scheduled assessments. No significant difference was shown between the 2 groups in AE incidence. Additionally, significant improvements in ADL, CFA, and GMFM were observed in the hUC-MSC group compared with the control group. In addition, the standard uptake value of 18F-FDG was markedly increased in 3 out of 5 patients from the hUC-MSC group at 12 months after transplantation.

CONCLUSIONS

Our clinical data showed that hUC-MSC transplantation was safe and effective at improving the gross motor and comprehensive function of children with CP when combined with rehabilitation. Recovery of cerebral metabolic activity might play an essential role in the improvements in brain function in patients with CP. The therapeutic window, transfusion route, and dosage in our study were considerable for reference in clinical application.

TRIAL REGISTRATION

Chictr.org.cn, ChiCTR1800016554. Registered 08 June 2018-retrospectively registered. The public title was "Randomized trial of umbilical cord-derived mesenchymal stem cells for cerebral palsy."

Stem cell therapy for preventing neonatal diseases in the 21st century: Current understanding and challenges

Diseases of the preterm newborn such as bronchopulmonary dysplasia, necrotizing enterocolitis, cerebral palsy, and hypoxic-ischemic encephalopathy continue to be major causes of infant mortality and long-term morbidity. Effective therapies for the prevention or treatment for these conditions are still lacking as recent clinical trials have shown modest or no benefit. Stem cell therapy is rapidly emerging as a novel therapeutic tool for several neonatal diseases with encouraging pre-clinical results that hold promise for clinical translation. However, there are a number of unanswered questions and facets to the development of stem cell therapy as a clinical intervention. There is much work to be done to fully elucidate the mechanisms by which stem cell therapy is effective (e.g., anti-inflammatory versus pro-angiogenic), identifying important paracrine mediators, and determining the timing and type of therapy (e.g., cellular versus secretomes), as well as patient characteristics that are ideal. Importantly, the interaction between stem cell therapy and current, standard-of-care interventions is nearly completely unknown. In this review, we will focus predominantly on the use of mesenchymal stromal cells for neonatal diseases, highlighting the promises and challenges in clinical translation towards preventing neonatal diseases in the 21st century.

Intravenous infusion of mesenchymal stem cells promotes functional recovery in a rat model of chronic cerebral infarction

OBJECTIVE

Intravenous infusion of mesenchymal stem cells (MSCs) derived from adult bone marrow improves behavioral function in rat models of cerebral infarction. Although clinical studies are ongoing, most studies have focused on the acute or subacute phase of stroke. In the present study, MSCs derived from bone marrow of rats were intravenously infused 8 weeks after the induction of a middle cerebral artery occlusion (MCAO) to investigate whether delayed systemic injection of MSCs improves functional outcome in the chronic phase of stroke in rats.

METHODS

Eight weeks after induction of the MCAO, the rats were randomized and intravenously infused with either MSCs or vehicle. Ischemic volume and behavioral performance were examined. Blood-brain barrier (BBB) integrity was assessed by quantifying the leakage of Evans blue into the brain parenchyma after intravenous infusion. Immunohistochemical analysis was also performed to evaluate the stability of the BBB.

RESULTS

Motor recovery was better in the MSC-treated group than in the vehicle-treated group, with rapid improvement (evident at 1 week post-infusion). In MSC-treated rats, reduced BBB leakage and increased microvasculature/repair and neovascularization were observed.

CONCLUSIONS

These results indicate that the systemic infusion of MSCs results in functional improvement, which is associated with structural changes in the chronic phase of cerebral infarction, including in the stabilization of the BBB.

Upcycling umbilical cords: bridging regenerative medicine with neonatology

Preterm birth is a major health concern that affects 10% of all worldwide deliveries. Many preterm infants are discharged from the hospital with morbidities that lead to an increased risk for neurodevelopmental impairment, recurrent hospitalizations, and life-long conditions. Unfortunately, the treatment of these conditions is palliative rather than curative, which calls for novel and innovative strategies. Progress in regenerative medicine has offered therapeutic options for many of these conditions. Specifically, human umbilical cord mesenchymal stem cells (MSCs) and cord blood (UCB) cells have shown promise in treating adult-onset diseases. Unlike bone-marrow and embryonic derived stem cells, umbilical cord-derived cells are easily and humanely obtained, have low immunogenicity, and offer the potential of autologous therapy. While there are several studies to uphold the efficacy of umbilical cord MSCs in adult therapies, there remains an unmet need for the investigation of its use in treating neonates. The purpose of this review is to provide a summary of current information on the potential therapeutic benefits and clinical applicability of umbilical cord MSCs and UCB cells. Promising preclinical studies have now led to a research movement that is focusing on cell-based therapies for preterm infants.

Wharton' jelly mesenchymal stromal cell therapy for ischemic brain injury

Increasing evidence have supported that Wharton's jelly mesenchymal stem cell (WJ-MSCs) have immunomodulatory and protective effects against several diseases including kidney, liver pathologies, and heart injury. Few in vitro studies have reported that WJ-MSCs reduced inflammation in hippocampal slices after oxygen–glucose deprivation. We recently reported the neuroprotective effects of human WJ-MSCs (hWJ-MSCs) in rats exposed to a transient right middle cerebral artery occlusion. hWJ-MSCs transplantation significantly reduced brain infarction and microglia activation in the penumbra leading with a significant reduction of neurological deficits. Interestingly, the grafted hWJ-MSCs in the ischemic core were mostly incorporated into IBA1 (+) cells, suggesting that hWJ-MSCs were immunorejected by the host. The immune rejection of hWJ-MSCs was reduced in after cyclosporine A treatment. Moreover, the glia cell line-derived neurotrophic factor expression was significantly increased in the host brain after hWJ-MSCs transplantation. In conclusion, these results suggest that the protective effect of hWJ-MSCs may be due to the secretion of trophic factors rather than to the survival of grafted cells. This paper is a review article. Referred literature in this paper has been listed in the references section. The data sets supporting the conclusions of this article are available online by searching various databases, including PubMed. Some original points in this article come from the laboratory practice in our research center and the authors’ experiences.

Neuroprotective Action of Human Wharton's Jelly-Derived Mesenchymal Stromal Cell Transplants in a Rodent Model of Stroke

Wharton’s jelly-derived mesenchymal stromal cells (WJ-MSCs) have distinct immunomodulatory and protective effects against kidney, liver, or heart injury. Limited studies have shown that WJ-MSCs attenuates oxygen–glucose deprivation-mediated inflammation in hippocampal slices. The neuroprotective effect of intracerebral WJ-MSC transplantation against stroke has not been well characterized. The purpose of this study was to examine the neuroprotective effect of human WJ-MSC (hWJ-MSC) transplants in an animal model of stroke. Adult male Sprague–Dawley rats were anesthetized and placed in a stereotaxic frame. hWJ-MSCs, pre-labeled with chloromethyl benzamide 1,1’-dioctadecyl-3,3,3’3’- tetramethylindocarbocyanine perchlorate (CM-Dil), were transplanted to the right cerebral cortex at 10 min before a transient (60 min) right middle cerebral artery occlusion (MCAo). Transplantation of hWJ-MSCs significantly reduced neurological deficits at 3 and 5 days after MCAo. hWJ-MSC transplants also significantly reduced brain infarction and microglia activation in the penumbra. Grafted cells carrying CM-Dil fluorescence were identified at the grafted site in the ischemic core; these cells were mostly incorporated into ionized calcium-binding adaptor molecule (+) cells, suggesting these xenograft cells were immuno-rejected by the host. In another set of animals, hWJ-MSCs were transplanted in cyclosporine (CsA)-treated rats. hWJ-MSC transplants significantly reduced brain infarction, improved neurological function, and reduced neuroinflammation. Less phagocytosis of CM-dil-labeled grafted cells was found in the host brain after CsA treatment. Transplantation of hWJ-MSC significantly increased glia cell line-derived neurotrophic factor expression in the host brain. Taken together, our data support that intracerebral transplantation of hWJ-MSCs reduced neurodegeneration and inflammation in the stroke brain. The protective effect did not depend on the survival of grafted cells but may be indirectly mediated through the production of protective trophic factors from the transplants.

Prefrontal cortex dysfunction in hypoxic-ischaemic encephalopathy contributes to executive function impairments in rats: Potential contribution for attention-deficit/hyperactivity disorder

OBJECTIVES

The attention-deficit/hyperactivity disorder (ADHD) compromises the quality of life of individuals including adaptation to the social environment. ADHD aetiology includes perinatal conditions such as hypoxic-ischaemic events; preclinical studies have demonstrated attentional deficits and impulsive-hyperactive outcomes after neonatal hypoxic and/or ischaemic intervention, but data are missing to understand this relationship. Thus, the aim of this study was to evaluate executive function (EF) and impulsivity, and tissue integrity and dopaminergic function in the prefrontal cortex (PFC) of rats submitted to hypoxia-ischaemia (HI).

METHODS

At postnatal day (PND) 7, male Wistar rats were divided into control (n = 10) and HI groups (n = 11) and the HI procedure was conducted. At PND60, the animals were tested in the attentional set-shifting (ASS) task to EF and in the tolerance to delay of reward for assessment of impulsivity. After, morphological analysis and the dopaminergic system were evaluated in the PFC.

RESULTS

Animals subjected to HI had impairments in EF evidenced by a behavioural inflexibility that was correlated to PFC atrophy. Moreover, HI animals presented reduced D2 receptors in the ipsilateral side of ischaemia in the PFC.

CONCLUSIONS

Animals submitted to HI presented impaired EF associated with tissue atrophy and dopaminergic disturbance in the PFC.

Wharton's Jelly-Derived Mesenchymal Stem Cell Transplantation in a Patient with Hypoxic-Ischemic Encephalopathy: A Pilot Study

Wharton’s jelly-derived mesenchymal stem cells (WJ-MSCs) have been introduced as a possible therapy in hypoxic-ischemic encephalopathy (HIE). We report a 16-year-old boy who was treated with WJ-MSCs in the course of HIE due to post-cardiopulmonary resuscitation. He received a long period of mechanical ventilation and tracheostomy with spastic quadriparesis. He underwent the intrathecal (1×10⁶/kg in 3 mL), intramuscular (1×10⁶/kg in 20 mL) and intravenous (1×10⁶/kg in 30 mL) administrations of WJ-MSCs for each application route (twice a month for 2 months). After stem cell infusions, progressive improvements were shown in his neurological examination, neuroradiological, and neurophysiological findings. To our best knowledge, this is a pioneer project to clinically study the neural repair effect of WJ-MSCs in a patient with HIE.

Dose-Dependent Effect of Intravenous Administration of Human Umbilical Cord-Derived Mesenchymal Stem Cells in Neonatal Stroke Mice

Neonatal brain injury induced by stroke causes significant disability, including cerebral palsy, and there is no effective therapy for stroke. Recently, mesenchymal stem cells (MSCs) have emerged as a promising tool for stem cell-based therapies. In this study, we examined the safety and efficacy of intravenously administered human umbilical cord-derived MSCs (UC-MSCs) in neonatal stroke mice. Pups underwent permanent middle cerebral artery occlusion at postnatal day 12 (P12), and low-dose (1 × 10⁴) or high-dose (1 × 10⁵) UC-MSCs were administered intravenously 48 h after the insult (P14). To evaluate the effect of the UC-MSC treatment, neurological behavior and cerebral blood flow were measured, and neuroanatomical analysis was performed at P28. To investigate the mechanisms of intravenously injected UC-MSCs, systemic blood flowmetry, in vivo imaging and human brain-derived neurotrophic factor (BDNF) measurements were performed. Functional disability was significantly improved in the high-dose UC-MSC group when compared with the vehicle group, but cerebral blood flow and cerebral hemispheric volume were not restored by UC-MSC therapy. The level of exogenous human BDNF was elevated only in the cerebrospinal fluid of one pup 24 h after UC-MSC injection, and in vivo imaging revealed that most UC-MSCs were trapped in the lungs and disappeared in a week without migration toward the brain or other organs. We found that systemic blood flow was stable over the 10 min after cell administration and that there were no differences in mortality among the groups. Immunohistopathological assessment showed that the percent area of Iba1-positive staining in the peri-infarct cortex was significantly reduced with the high-dose UC-MSC treatment compared with the vehicle treatment. These results suggest that intravenous administration of UC-MSCs is safe for a mouse model of neonatal stroke and improves dysfunction after middle cerebral artery occlusion by modulating the microglial reaction in the peri-infarct cortex.

Mesenchymal Stem Cells Protect Against Hypoxia-Ischemia Brain Damage by Enhancing Autophagy Through Brain Derived Neurotrophic Factor/Mammalin Target of Rapamycin Signaling Pathway

Hypoxic-ischemic encephalopathy (HIE) is a serious disease for neonates. However, present therapeutic strategies are not effective enough for treating HIE. Previous study showed that mesenchymal stem cells (MSCs) can exert neuroprotective effects for brain damage, but its mechanism remains elusive. Using in vitro coculture of rat cortical primary neurons and MSCs in HI conditions, we demonstrated that MSCs help increase brain derived neurotrophic factor (BDNF) and autophagy markers (LC3II and Beclin1) in the cultures and decrease cells death (lactate dehydrogenase levels). We demonstrated a similar mechanism using an in vivo rat model of HI in combination with MSCs transplantation. Using a behavioral study, we further showed that MSCs transplantation into the rat brain after HI injury can attenuate behavioral deficits. Finally, we found that the increase in BDNF and autophagy related factors after HI injury combined with MSCs transplantation can be reversed by anti-BDNF treatment and strengthen the point that the protective effects of BDNF work through inhibition of the mammalin target of rapamycin (mTOR) pathway. Collectively, we proposed that coculture/transplantation of MSCs after HI injury leads to increased BDNF expression and a subsequent reduction in mTOR pathway activation that results in increased autophagy and neuroprotection. This finding gives a hint to explore new strategies for treating neonates with HIE. Stem Cells 2018;36:1109-1121.

From cord to caudate: characterizing umbilical cord blood stem cells and their paracrine interactions with the injured brain

Stem cells are proving to be a promising therapy for a wide range of pediatric disorders, from neonatal hypoxic-ischemic encephalopathy to pediatric leukemia. Owing to their low immunogenicity and ease of availability, umbilical cord blood (UCB) progenitor cells are increasingly replacing fetal- and adult-derived cells in therapeutic settings. Multiple environmental and demographic factors affect the number and type of stem cells extracted from UCB, and these differences have been associated with disparities in outcomes after transplantation. To avoid variations in efficacy, as well as the potential adverse effects of stem cell transplantation, evaluation of the stem cell secretome is critical to identify key paracrine signals released by the stem cells that could be used to provide similar neuroprotective effects to stem cell transplantation. This article describes the cell types found in UCB and reviews the available literature surrounding the effects of collection timing and volume, maternal risk factors, delivery characteristics, and neonatal demographics on the cellular composition of UCB. In addition, the current findings regarding the stem cell secretome are discussed to identify factors that could be used to supplement or replace stem cell transplantation in pediatric neuroprotection.

Goreisan Inhibits Upregulation of Aquaporin 4 and Formation of Cerebral Edema in the Rat Model of Juvenile Hypoxic-Ischemic Encephalopathy

Secondary cerebral edema regulation is of prognostic significance in hypoxic-ischemic encephalopathy (HIE), and aquaporin 4 (AQP4) plays an important role in the pathogenesis of cerebral edema. The traditional Japanese herbal medicine Goreisan relieves brain edema in adults; however, its effect and pharmacological mechanism in children are unknown. We investigated the effects of Goreisan on HIE-associated brain edema and AQP4 expression in a juvenile rat model, established by combined occlusion of middle cerebral and common carotid arteries. Magnetic resonance imaging showed that the lesion areas were significantly smaller in the Goreisan- (2 g/kg) treated group than in the nontreated (saline) group at 24 and 48 h postoperatively. AQP4 mRNA levels in the lesion and nonlesion sides were significantly suppressed in the Goreisan group compared with the nontreated group 36 h postoperatively. Western blotting revealed that levels of AQP4 protein were significantly decreased in the Goreisan group compared with the nontreated group in the lesion side 72 h postoperatively, but not at 12 or 36 h. After 14 days, the Goreisan group had a significantly better survival rate. These findings suggest that Goreisan suppresses brain edema in HIE and improves survival in juvenile rats, possibly via regulation of AQP4 expression and function.

Neonatal Hypoxia Ischaemia: Mechanisms, Models, and Therapeutic Challenges

Neonatal hypoxia-ischaemia (HI) is the most common cause of death and disability in human neonates, and is often associated with persistent motor, sensory, and cognitive impairment. Improved intensive care technology has increased survival without preventing neurological disorder, increasing morbidity throughout the adult population. Early preventative or neuroprotective interventions have the potential to rescue brain development in neonates, yet only one therapeutic intervention is currently licensed for use in developed countries. Recent investigations of the transient cortical layer known as subplate, especially regarding subplate's secretory role, opens up a novel set of potential molecular modulators of neonatal HI injury. This review examines the biological mechanisms of human neonatal HI, discusses evidence for the relevance of subplate-secreted molecules to this condition, and evaluates available animal models. Neuroserpin, a neuronally released neuroprotective factor, is discussed as a case study for developing new potential pharmacological interventions for use post-ischaemic injury.

Neural differentiation of human Wharton's jelly-derived mesenchymal stem cells improves the recovery of neurological function after transplantation in ischemic stroke rats

Human Wharton's jelly-derived mesenchymal stem cells (hWJ-MSCs) have excellent proliferative ability, differentiation ability, low immunogenicity, and can be easily obtained. However, there are few studies on their application in the treatment of ischemic stroke, therefore their therapeutic effect requires further verification. In this study, hWJ-MSCs were transplanted into an ischemic stroke rat model via the tail vein 48 hours after transient middle cerebral artery occlusion. After 4 weeks, neurological functions of the rats implanted with hWJ-MSCs were significantly recovered. Furthermore, many hWJ-MSCs homed to the ischemic frontal cortex whereby they differentiated into neuron-like cells at this region. These results confirm that hWJ-MSCs transplanted into the ischemic stroke rat can differentiate into neuron-like cells to improve rat neurological function and behavior.

Combination of butylphthalide with umbilical mesenchymal stem cells for the treatment of delayed encephalopathy after carbon monoxide poisoning

Delayed encephalopathy after carbon monoxide (CO) poisoning (DEACMP) is still a clinical challenge. This study aimed to investigate the efficacy of combined therapy of mesenchymal stem cell (MSC) transplantation and butylphthalide in DEACMP patients.Forty-two DEACMP patients were treated with 1 of the 3 therapies: combined therapy of MSC transplantation and butylphthalide; MSC transplantation alone; or hyperbaric oxygen therapy. The MSCs were alternatively injected into the subarachnoid space and the carotid artery using a self-made high-pressure injector. The Mini-Mental State Examination and the Barthel index of activities of daily living were administered before the treatment, and at 1 month, 3 months, and 6 months after the treatment. Computed tomography and magnetic resonance imaging results before and after the treatment were compared.At 1 month, 3 months, and 6 months after the treatment, the Mini-Mental State Examination scores and the Barthl scores were significantly higher in patients with the combined therapy of MSC transplantation and butylphthalide than those in patients with MSC transplantation alone or hyperbaric oxygen therapy (all P < 0.0001). No significant adverse events occurred.The combination of MSC transplantation and butylphthalide is safe and effective in treating DEACMP.

Neuroprotective Strategies after Neonatal Hypoxic Ischemic Encephalopathy

Neonatal hypoxic ischemic encephalopathy (HIE) is a devastating disease that primarily causes neuronal and white matter injury and is among the leading cause of death among infants. Currently there are no well-established treatments; thus, it is important to understand the pathophysiology of the disease and elucidate complications that are creating a gap between basic science and clinical translation. In the development of neuroprotective strategies and translation of experimental results in HIE, there are many limitations and challenges to master based on an appropriate study design, drug delivery properties, dosage, and use in neonates. We will identify understudied targets after HIE, as well as neuroprotective molecules that bring hope to future treatments such as melatonin, topiramate, xenon, interferon-beta, stem cell transplantation. This review will also discuss some of the most recent trials being conducted in the clinical setting and evaluate what directions are needed in the future.

Mesenchymal Stem Cells from Wharton's Jelly and Amniotic Fluid

The discovery of mesenchymal stem cells (MSCs) in perinatal sources, such as the amniotic fluid (AF) and the umbilical connective tissue, the so-called Wharton's jelly (WJ), has transformed them into promising stem cell grafts for the application in regenerative medicine. The advantages of AF-MSCs and WJ-MSCs over adult MSCs, such as bone marrow-derived mesenchymal stem cells (BM-MSCs), include their minimally invasive isolation procedure, their more primitive cell character without being tumourigenic, their low immunogenicity and their potential autologous application in congenital disorders and when cryopreserved in adulthood. This chapter gives an overview of the biology of AF-MSCs and WJ-MSCs, and their regenerative potential based on the results of recent preclinical and clinical studies. In the end, open questions concerning the use of WJ-MSCs and AF-MSCs in regenerative medicine will be emphasized.

Stromal Cell-Derived Factor-1α Plays a Crucial Role Based on Neuroprotective Role in Neonatal Brain Injury in Rats

Owing to progress in perinatal medicine, the survival of preterm newborns has markedly increased. However, the incidence of cerebral palsy has risen in association with increased preterm birth. Cerebral palsy is largely caused by cerebral hypoxic ischemia (HI), for which there are no effective medical treatments. We evaluated the effects of stromal cell-derived factor-1α (SDF-1α) on neonatal brain damage in rats. Left common carotid (LCC) arteries of seven-day-old Wistar rat pups were ligated, and animals were exposed to hypoxic gas to cause cerebral HI. Behavioral tests revealed that the memory and spatial perception abilities were disturbed in HI animals, and that SDF-1α treatment improved these cognitive functions. Motor coordination was also impaired after HI but was unimproved by SDF-1α treatment. SDF-1α reduced intracranial inflammation and induced cerebral remyelination, as indicated by the immunohistochemistry results. These data suggest that SDF-1α specifically influences spatial perception abilities in neonatal HI encephalopathy.

Could cord blood cell therapy reduce preterm brain injury?

Major advances in neonatal care have led to significant improvements in survival rates for preterm infants, but this occurs at a cost, with a strong causal link between preterm birth and neurological deficits, including cerebral palsy (CP). Indeed, in high-income countries, up to 50% of children with CP were born preterm. The pathways that link preterm birth and brain injury are complex and multifactorial, but it is clear that preterm birth is strongly associated with damage to the white matter of the developing brain. Nearly 90% of preterm infants who later develop spastic CP have evidence of periventricular white matter injury. There are currently no treatments targeted at protecting the immature preterm brain. Umbilical cord blood (UCB) contains a diverse mix of stem and progenitor cells, and is a particularly promising source of cells for clinical applications, due to ethical and practical advantages over other potential therapeutic cell types. Recent studies have documented the potential benefits of UCB cells in reducing brain injury, particularly in rodent models of term neonatal hypoxia–ischemia. These studies indicate that UCB cells act via anti-inflammatory and immuno-modulatory effects, and release neurotrophic growth factors to support the damaged and surrounding brain tissue. The etiology of brain injury in preterm-born infants is less well understood than in term infants, but likely results from episodes of hypoperfusion, hypoxia–ischemia, and/or inflammation over a developmental period of white matter vulnerability. This review will explore current knowledge about the neuroprotective actions of UCB cells and their potential to ameliorate preterm brain injury through neonatal cell administration. We will also discuss the characteristics of UCB-derived from preterm and term infants for use in clinical applications.