Role of Nuclear-Receptor-Related 1 in the Synergistic Neuroprotective Effect of Umbilical Cord Blood and Erythropoietin Combination Therapy in Hypoxic Ischemic Encephalopathy

Melatonin promotes cell cycle progression of neural stem cells subjected to manganese via Nurr1

Excessive exposure to manganese (Mn) through drinking water and food during pregnancy significantly heightens the likelihood of neurodevelopmental damage in offspring. Multiple studies have indicated that melatonin (Mel) may help to relieve neurodevelopmental disorders caused by Mn, but potential mechanisms underlying this effect require further exploration. Here, we utilized primary neural stem cells (NSCs) as a model to elucidate the molecular mechanism underlying the protective function of Mel on Mn-induced cell proliferation dysfunction and cycle arrest. Our results showed that Mn disrupted the cell cycle in NSCs by suppressing positive regulatory proteins (CDK2, Cyclin A, Cyclin D1, and E2F1) and enhancing negative ones (p27KIP1 and p57KIP2), leading to cell proliferation dysfunction. Mel inhibited the Mn-dependent changes to these proteins and the cell cycle through nuclear receptor-related protein 1 (Nurr1), thus alleviating the proliferation dysfunction. Knockdown of Nurr1 using lentivirus-expressed shRNA in NSCs resulted in a diminished protective effect of Mel. We concluded that Mel mitigated Mn-induced proliferation dysfunction and cycle arrest in NSCs through Nurr1.

Maintenance of the synergistic effects of cord blood cells and erythropoietin combination therapy after additional cord blood infusion in children with cerebral palsy: 1-year open-label extension study of randomized placebo-controlled trial

BACKGROUND

This 1-year open-label extension study aimed to identify the persistent synergistic effects of allogeneic umbilical cord blood (UCB) cells and erythropoietin (EPO) in children with cerebral palsy (CP) for up to 2 years.

METHODS

This open-label extension study followed children with CP who were enrolled in the previous randomized, double blind, placebo-controlled trial. The following groups from the first trial were maintained: (A) UCB + EPO, (B) UCB, (C) EPO, and (D) only placebo, and all the participants had continued active rehabilitation. This extended study started 3 months after termination of the first trial, which had a 1-year follow-up duration. All subjects received single additional UCB intravenous infusion at the extension baseline regardless of their initial allocation. Outcome measures were the gross motor performance measure (GMPM), gross motor function measure-66 (GMFM-66), and Bayley scales of infant development-II (BSID-II), which were followed at 3, 6, and 12 months after the extension baseline. Changes in the outcome scores from the baseline values of the previous trial and this study were analysed.

RESULTS

Sixty-nine children (4.29 ± 1.28 years, M:F = 34:35) were included in this study. Each group showed improvements in the outcome measures at 12 months after additional UCB infusion compared to the baseline scores, except for GMFM and GMPM in Group C which were elevated at 3 and 6 months post-therapy. Total subject analyses did not show significant differences in the outcome measures between the four different groups at 3, 6 and 12 months after additional UCB therapy. However, patients with severe dysfunction, whose GMFCS levels were IV and V, revealed a larger improvement of the GMPM score in Group A than in Group D (Ps < 0.05) from the baseline value of the previous trial. The changes in BSID-II mental scale scores were positively correlated with the number of administered total nucleated cells per unit body weight during this one-year extension study period (r = 0.536, P = 0.001).

CONCLUSIONS

These results suggest that when administering UCB to treat patients with CP, combination therapy with EPO is more effective, and the effect might last as long as 2 years, especially in patients with severe impairments.

TRIAL REGISTRATION

CHA Bundang Medical Center IRB, No. 2015-06-093, approved on July 29, 2015, ( https://www.e-irb.com:3443/devlpg/nlpgS200.jsp ), ClinicalTrials.gov, NCT03130816, retrospectively registered on April 27, 2017 ( https://clinicaltrials.gov/ct2/show/NCT03130816?term=NCT03130816&draw=2&rank=1 ).

Neuroprotective effects of oxymatrine on hypoxic-ischemic brain damage in neonatal rats by activating the Wnt/β-catenin pathway

Neuronal apoptosis is a major pathological process associated with neurological dysfunction in neonates after hypoxic-ischemic brain damage (HIBD). Our previous study demonstrated that oxymatrine (OMT) exerts potential neuroprotective effects on neonatal rats subjected to hypoxic-ischemic insult. However, the underlying molecular mechanism remains unclear. In this study, we investigated the effects of OMT-mediated neuroprotection on neonatal HIBD by attempting to determine its effect on the Wnt/β-catenin signaling pathway and explored the underlying mechanism. Both 7-day-old rat pups and primary hippocampus neurons were used to establish the HIBD and oxygen-glucose deprivation (OGD) injury models, respectively. Our results demonstrated that OMT treatment significantly increased cerebral blood flow and reduced S100B concentration, infarct volume, and neuronal apoptosis in neonatal rats. In vitro, OMT markedly increased cell viability and MMP level and decreased DNA damage. Moreover, OMT improved the mRNA and protein levels of Wnt1 and β-catenin, inhibited the expression of DKK1 and GSK-3β, enhanced the nuclear transfer of β-catenin, and promoted the binding activity of β-catenin with Tcf-4; however, it downregulated the expression of cleaved caspase-3 and cleaved caspase-9. Notably, the introduction of XAV-939 (a Wnt/β-catenin signaling inhibitor) reversed the positive effects of OMT both in vivo and in vitro. Collectively, our findings demonstrated that OMT exerted a neuroprotective effect on neonatal HIBD by inhibiting neuronal apoptosis, which was partly via the activation of the Wnt/β-catenin signaling pathway.