Intratracheal administration of umbilical cord-derived mesenchymal stem cells attenuates hyperoxia-induced multi-organ injury via heme oxygenase-1 and JAK/STAT pathways

BACKGROUND Bronchopulmonary dysplasia(BPD)is not merely a chronic lung disease,but a systemic condition with multiple organs implications predominantly associated with hyperoxia exposure.Despite advances in current management strategies,limited progress has been made in reducing the BPD-related systemic damage.Meanwhile,although the protective effects of human umbilical cord-derived mesenchymal stem cells(hUC-MSCs)or their exosomes on hyperoxia-induced lung injury have been explored by many researchers,the underlying mechanism has not been addressed in detail,and few studies have focused on the therapeutic effect on systemic multiple organ injury.AIM To investigate whether hUC-MSC intratracheal administration could attenuate hyperoxia-induced lung,heart,and kidney injuries and the underlying regulatory mechanisms.METHODS Neonatal rats were exposed to hyperoxia(80%O_(2)),treated with hUC-MSCs intratracheal(iT)or intraperitoneal(iP)on postnatal day 7,and harvested on postnatal day 21.The tissue sections of the lung,heart,and kidney were analyzed morphometrically.Protein contents of the bronchoalveolar lavage fluid(BALF),myeloper oxidase(MPO)expression,and malondialdehyde(MDA)levels were examined.Pulmonary inflammatory cytokines were measured via enzyme-linked immunosorbent assay.A comparative transcriptomic analysis of differentially expressed genes(DEGs)in lung tissue was conducted via RNA-sequencing.Subsequently,we performed reverse transcription-quantitative polymerase chain reaction and western blot analysis to explore the expression of target mRNA and proteins related to inflammatory and oxidative responses.RESULTS iT hUC-MSCs administration improved pulmonary alveolarization and angiogenesis(P<0.01,P<0.01,P<0.001,and P<0.05 for mean linear intercept,septal counts,vascular medial thickness index,and microvessel density respectively).Meanwhile,treatment with hUC-MSCs iT ameliorated right ventricular hypertrophy(for Fulton’s index,P<0.01),and relieved reduced nephrogenic zone width(P<0.01)and glomerular diameter(P<0.001)in kidneys.Among the beneficial effects,a reduction of BALF protein,MPO,and MDA was observed in hUC-MSCs groups(P<0.01,P<0.001,and P<0.05 respectively).Increased pro-inflammatory cytokines tumor necrosis factor-alpha,interleukin(IL)-1β,and IL-6 expression observed in the hyperoxia group were significantly attenuated by hUC-MSCs administration(P<0.01,P<0.001,and P<0.05 respectively).In addition,we observed an increase in anti-inflammatory cytokine IL-10 expression in rats that received hUC-MSCs iT compared with rats reared in hyperoxia(P<0.05).Transcriptomic analysis showed that the DEGs in lung tissues induced by hyperoxia were enriched in pathways related to inflammatory responses,epithelial cell proliferation,and vasculature development.hUC-MSCs administration blunted these hyperoxia-induced dysregulated genes and resulted in a shift in the gene expression pattern toward the normoxia group.hUC-MSCs increased heme oxygenase-1(HO-1),JAK2,and STAT3 expression,and their phosphorylation in the lung,heart,and kidney(P<0.05).Remarkably,no significant difference was observed between the iT and iP administration.CONCLUSION iT hUC-MSCs administration ameliorates hyperoxia-induced lung,heart,and kidney injuries by activating HO-1 expression and JAK/STAT signaling.The therapeutic benefits of local iT and iP administration are equivalent.

Prior transfusion of umbilical cord mesenchymal stem cells can effectively alleviate symptoms of motion sickness in mice through interleukin 10 secretion

BACKGROUND Motion sickness(MS)is a disease that occurs during unbalanced movement,characterized by gastrointestinal symptoms and autonomic nervous system activation.Current clinical treatments for MS are limited.Recent evidence indicates that the levels of pro-inflammatory cytokines increase during MS and are associated with an inner ear immune imbalance.In the present study,mesenchymal stem cells(MSCs)have been shown to exert strong immunosuppressive effects.AIM To explore whether umbilical cord-derived mesenchymal stem cells(UC-MSCs)can prevent the occurrence of MS,and the underlying mechanism regulated by MSCs in a mouse model of MS.METHODS A total of 144(equal numbers of males and females)5wkold BALB/c mice were randomly divided into five groups:Normal group(n=16),MS group(n=32),MSCs group(n=32),MS+MSCs group(n=32),and MS+AS101/MSCs group(n=32).The MSCs group(n=32),MS+MSCs group(n=32),and MS+AS101/MSCs group(n=32)were preventively transplanted with UC-MSCs or AS101-treated UC-MSCs(1×106 cells/mouse).Mice in the MS(n=32),MS+MSCs,and MS+AS101/MSCs groups were subjected to rotation on a centrifuge for 10 min at 8×g/min for MS model establishment on days 3,5,8,and 10 after UC-MSCs injection.The Morris water maze(MWM)test was used to observe the symptom of dizziness.Enzyme-linked immunosorbent assay(ELISA)and reverse transcription-quantitative polymerase chain reaction(RT-qPCR)were used to detect the levels of inflammatory cytokines in mice peripheral blood and the petrous part of the temporal bone samples.Western blot analysis was performed to analyze the JAK2/STAT3 signaling pathway in the cochlear tissues.Histological examination was performed by hematoxylin and eosin(HE)staining for conventional morphological evaluation in the petrous part of temporal bone samples.RESULTS The MWM test demonstrated that UC-MSCs improved the symptoms of MS.The MS+MSCs group was faster than the MS group on days 3 and 5(P=0.036 and P=0.002,respectively).ELISA and RT-qPCR showed that the serum and mRNA levels of interleukin-10(IL-10)in the cochlear tissues were increased after transplantation with UC-MSCs(MS+MSCs group vs MS group at 3 and 5 d,P=0.002 and cP<0.001,respectively).RT-qPCR results confirmed a significant increase in IL-10 levels at four time points(MS+MSCs group vs MS group,P=0.009,P=0.009,P=0.048,and P=0.049,respectively).This suggested that UCMSCs reduced the sensitivity of the vestibular microenvironment by secreting IL-10.Moreover,Western blot analysis showed that the MSCs activated the JAK2/STAT3 signaling pathway in the cochlear tissues.The levels of IL-10,IL-10RA,JAK2,STAT3,and phosphorylated JAK2 and STAT3 in the MS+MSCs group were increased compared to those of the MS group(P<0.05).The morphological changes in the four groups showed no significant differences.The role of IL-10 secretion on the ability of UC-MSCs to successfully improve the symptoms of MS was confirmed by the diminished therapeutic effects associated with treatment with the IL-10 inhibitor ammonium trichloro(dioxoethylene-o,o′)tellurate(AS101).CONCLUSION Prophylactic transplantation of UC-MSCs can alleviate the clinical symptoms of MS in mice,particularly at 3-5 d after preventive transplantation.The mechanism for UC-MSCs to reduce the sensitivity of vestibular cortex imbalance may be the secretion of IL-10.The next step is to demonstrate the possibility of curing MS in the vestibular environment by intermittent transplantation of MSCs.Above all,MSCs are expected to become a new method for the clinical prevention and treatment of MS.

Therapeutic effect of placenta-derived mesenchymal stem cells on hypoxic-ischemic brain damage in rats

Background:Oxidative stress is involved in the development of hypoxic-ischemic brain damage(HIBD).In this study,we investigated the therapeutic efcts of placenta-derived mesenchymal stem cells(PD-MSCs)and explored the N F-E2-related factor-2/heme oxygenase-1(Nrf2/HO-1)signaling pathway in treating HIBD.Methods:P7 rats were subjected to hypoxic-ischemic brain injury and randomly divided into four groups(control,HIBD,HIBD+PD-MSCs,and HIBD+fbroblasts).Forty-eight hours after the induction of HIBD,5×10^(5)of PD-MSCs were injected into cerebral tissue in the HIBD+PD-MSCs group,while the same dose of fibroblas ts were injected in the HIBD+fibroblasts group.Morris Water Maze,gross and pathological changes were tested at P28.The level of malondialdehyde(MDA)was detected in rats'hippocampus.RT-PCR and western blot analysis were used to evaluate the changes of Nrf2/HO-1.Results:The HIBD group showed significantly longer escape latency and a lower frequency of original platform crossing in the Morris Water M laze compared with the control group.Rats receiving PD MSCs showed significant improvement of HIBD.The pathological changes were evident after HIBD,but ameliorated in the PD-MSCs group.Compared with the control group,HO-1 and Nrf2 were up-regulated at gene and protein levels in the HI brain,beginning at 6 hours and peaking at 48 hours(P<0.05).The expression of HO-1 and Nrf2 in the PD-MSCs treatment group was more pronounced than in the HBD group(P<0.01).PD MSCs also decreased MDA production in the brain tissue.Conclusion:These results demonstrate that PD-MSCs have neuroprotective effect during the treatment of HIBD and that the mechanism may be partly due to alleviating oxidative stress.