Background: The channel-forming protein Pannexin1（Panx1） has been implicated in both human studies and animal models of chronic pain, but the underlying mechanisms remain incompletely understood.Methods: Wild-type（WT, n=24）, global Panx1 KO（n=24）, neuron-specific Panx1 KO（n=20）, and glia-specific Panx1KO（n=20） mice were used in this study at Albert Einstein College of Medicine. The von Frey test was used to quantify pain sensitivity in these mice following complete Freund's adjuvant（CFA） injection（7, 14, and 21 d）. The qRT-PCR was employed to measure mRNA levels of Panx1, Panx2, Panx3, Cx43, Calhm1, and β-catenin. Laser scanning confocal microscopy imaging, Sholl analysis, and electrophysiology were utilized to evaluate the impact of Panx1 on neuronal excitability and morphology in Neuro2a and dorsal root ganglion neurons（DRGNs） in which Panx1 expression or function was manipulated. Ethidium bromide（EtBr） dye uptake assay and calcium imaging were employed to investigate the role of Panx1 in adenosine triphosphate（ATP） sensitivity. β-galactosidase（β-gal） staining was applied to determine the relative cellular expression levels of Panx1 in trigeminal ganglia（TG） and DRG of transgenic mice.Results: Global or neuron-specific Panx1 deletion markedly decreased pain thresholds after CFA stimuli（7, 14, and 21 d; P<0.01 vs. WT group）, indicating that Panx1 was positively correlated with pain sensitivity. In Neuro2a, global Panx1 deletion dramatically reduced neurite extension and inward currents compared to the WT group（P<0.05）,revealing that Panx1 enhanced neurogenesis and excitability. Similarly, global Panx1 deletion significantly suppressed Wnt/β-catenin dependent DRG neurogenesis following 5 d of nerve growth factor（NGF） treatment（P<0.01 vs. WT group）. Moreover, Panx1 channels enhanced DRG neuron response to ATP after CFA injection（P<0.01 vs. Panx1KO group）. Furthermore, ATP release increased Ca 2+ responses in DRGNs and satellite glial cells surrounding them following 7 d of CFA treatment（P<0.01 vs. Panx1 KO group）, suggesting that Panx1 in glia also impacts exaggerated neuronal excitability. Interestingly, neuron-specific Panx1 deletion was found to markedly reduce differentiation in cultured DRGNs, as evidenced by stunted neurite outgrowth（P<0.05 vs. Panx1 KO group; P<0.01 vs. WT group or GFAP-Cre group）, blunted activation of Wnt/β-catenin signaling（P<0.01 vs. WT, Panx1 KO and GFAP-Cre groups）,and diminished cell excitability（P<0.01 vs. GFAP-Cre group） and response to ATP stimulation（P<0.01 vs. WT group）.Analysis of β-gal staining showed that cellular expression levels of Panx1 in neurons are significantly higher（2.5-fold increase） in the DRG than in the TG.Conclusions: The present study revealed that neuronal Panx1 is a prominent driver of peripheral sensitivity in the setting of inflammatory pain through cell-autonomous effects on neuronal excitability. This hyperexcitability dependence on neuronal Panx1 contrasts with inflammatory orofacial pain, where similar studies revealed a prominent role for glial Panx1. The apparent differences in Panx1 expression in neuronal and non-neuronal TG and DRG cells are likely responsible for the distinct impact of these cell types in the two pain models.

The pro-inflammatory activation of microglia is a hallmark of Alzheimer’s disease (AD), and this process involves a switch from oxidative phosphorylation (OXPHOS) toward glycolysis. Here, we show how a positive feedback loop in microglia drives AD pathogenesis, and we demonstrate that inhibiting this cycle in microglia can ameliorate Aβ burden and cognitive deficits in an AD mouse model (5XFAD). After first detecting elevated histone lactylation in brain samples from both 5XFAD mice and individuals with AD, we observed that H4K12la levels are elevated in Aβ plaque-adjacent microglia. This lactate-dependent histone modification is enriched at the promoters of glycolytic genes and activates transcription, thereby increasing glycolytic activity. Ultimately, the glycolysis/H4K12la/PKM2 positive feedback loop exacerbates microglial dysfunction in AD. Pharmacologic inhibition of PKM2 attenuated microglial activation, and microglia-specific ablation of Pkm2 improved spatial learning and memory in AD mice. Thus, our study illustrates that disruption of the positive feedback loop may be a potential therapeutic approach for the treatment of AD.

Stem cell therapy is promising for neural repair in devastating traumatic brain injury (TBI). However, the low survival and differentiation rates of transplanted stem cells are main obstacles to efficient stem cell therapy in TBI. Stromal cell-derived factor-1 (SDF-1) and its receptor CXCR4 are key factors that regulate the survival, recruitment, and differentiation of stem cells. Herein, we synthesized a sodium alginate (SA)/collagen type I (Col)/SDF-1 hydrogel and investigated whether the SA/Col/SDF-1 hydrogel loaded with bone marrow-derived mesenchymal stem cells (BMSCs) had therapeutic effects on a TBI model. Our results showed that the SA/Col/SDF-1 scaffold could stably release SDF-1 and provide biocompatible and biodegradable microenvironment for the survival, migration, and neuronal differentiation of BMSCs in vitro . In a rat model of TBI, the SA/Col/SDF-1 hydrogel loaded with BMSCs significantly ameliorated motor and cognition dysfunction and relieved anxiety and depressive-like behaviors. In addition, the BMSCs/SA/Col/SDF-1 scaffold reduced brain lesions and neuronal cell death and mitigated neuroinflammation. Further studies demonstrated that the BMSCs/SA/Col/SDF-1 hydrogel promoted the migration of BMSCs in the lesions and partly enhanced neurogenesis by activating the SDF-1/CXCR4-mediated FAK/PI3K/AKT pathway. Taken together, our results indicate that the SA/Col/SDF-1 scaffold loaded with BMSCs exerts neuroreparative effects in a TBI rat model, and thus, it may serve as an alternative neural regeneration scaffold for brain injury repair.

Astrocytes are an abundant subgroup of cells in the central nervous system (CNS) that play a critical role in controlling neuronal circuits involved in emotion, learning, and memory. In clinical cases, multiple chronic brain diseases may cause psychosocial and cognitive impairment, such as depression and Alzheimer's disease (AD). For years, complex pathological conditions driven by depression and AD have been widely perceived to contribute to a high risk of disability, resulting in gradual loss of self-care ability, lower life qualities, and vast burden on human society. Interestingly, correlational research on depression and AD has shown that depression might be a prodrome of progressive degenerative neurological disease. As a kind of multifunctional glial cell in the CNS, astrocytes maintain physiological function via supporting neuronal cells, modulating pathologic niche, and regulating energy metabolism. Mounting evidence has shown that astrocytic dysfunction is involved in the progression of depression and AD. We herein review the current findings on the roles and mechanisms of astrocytes in the development of depression and AD, with an implication of potential therapeutic avenue for these diseases by targeting astrocytes.

Background Traumatic brain injury (TBI) is a common neurotrauma leading to brain dysfunction and death. Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) hold promise in the treatment of TBI. However, their efficacy is modest due to low survival and differentiation under the harsh microenvironment of the injured brain. MG53, a member of TRIM family protein, plays a vital role in cell and tissue damage repair. The present study aims to test whether MG53 preserves hUC-MSCs against oxidative stress and enhances stem cell survival and efficacy in TBI treatment. Methods In this study, we performed a series of in vitro and in vivo experiments in hUC-MSCs and mice to define the function of MG53 enhancing survival, neurogenesis, and therapeutic efficacy of stem cells in murine traumatic brain injury. Results We found that recombinant human MG53 (rhMG53) protein protected hUC-MSCs against H 2 O 2 -induced oxidative damage and stimulated hUC-MSC proliferation and migration. In a mouse model of contusion-induced TBI, intravenous administration of MG53 protein preserved the survival of transplanted hUC-MSCs, mitigated brain edema, reduced neurological deficits, and relieved anxiety and depressive-like behaviors. Co-treatment of MG53 and hUC-MSCs enhanced neurogenesis by reducing apoptosis and improving PI3K/Akt-GSK3β signaling. Conclusion MG53 enhances the efficacy of hUC-MSCs in the recovery of TBI, indicating that such adjunctive therapy may provide a novel strategy to lessen damage and optimize recovery for brain injury.

Stem cell transplantation is a promising therapy for traumatic brain injury (TBI), but low efficiency of survival and differentiation of transplanted stem cells limits its clinical application. Histone deacetylase 1 (HDAC1) plays important roles in self-renewal of stem cells as well as the recovery of brain disorders. However, little is known about the effects of HDAC1 on the survival and efficacy of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) in vivo. In this study, our results showed that HDAC1 silence promoted hUC-MSCs engraftment in the hippocampus and increased the neuroprotective effects of hUC-MSCs in TBI mouse model, which was accompanied by improved neurological function, enhanced neurogenesis, decreased neural apoptosis, and reduced oxidative stress in the hippocampus. Further mechanistic studies revealed that the expressions of phosphorylated PTEN (p-PTEN), phosphorylated Akt (p-Akt), and phosphorylated GSK-3β (p-GSK-3β) were upregulated. Intriguingly, the neuroprotective effects of hUC-MSCs with HDAC1 silence on behavioral performance of TBI mice was markedly attenuated by LY294002, an inhibitor of the PI3K/AKT pathway. Taken together, our findings suggest that hUC-MSCs transplantation with HDAC1 silence may provide a potential strategy for treating TBI in the future.

Chimeric RNAs are transcripts composed of RNA fragments from different genes and are traditionally well-known cancer-causing genetic events. Recent studies show chimeric RNAs being present in multiple non-neoplastic tissues and cells, suggesting that at least some may have roles in normal physiology. However, chimeric RNAs and their implications in brain development and neural differentiation have not been formally studied. Here, we firstly characterized the landscape of chimeric RNAs in human infant brain tissues and identified 599 chimeric RNAs. Through a series of filtering, 22 were selected and tested in a neural differentiation process starting from stem cells. Ten were validated experimentally. One of these ten chimeric RNAs, DUS4L-BCAP29, dramatically increased when human umbilical mesenchymal stem cells were induced for neural differentiation. Consistently, we found that overexpressed DUS4L-BCAP29 effectively promoted neural differentiation. Our results support the important role(s) chimeric RNAs play in neural differentiation, and are consistent with the new notion that chimeric RNAs also exist in normal physiology, and likely serve biological purposes.

目的:探讨重组人MG53蛋白(rhMG53)作为干细胞低温保护剂的特殊组分对小鼠骨髓间充质干细胞(BMSCs)冷冻保存后生物学特性的影响.方法:常规培养BMSCs,分为对照组(DMEM/F12培养基、FBS、DMSO的体积比为5:4:1并添加30 mg/L BSA)和rhMG53组(DMEM/F12培养基、FBS、DMSO的体积比为5:4:1并添加30 mg/L rhMG53)冻存.冻存1 a后,复苏细胞,qRT-PCR检测两组细胞冻存复苏后干性相关基因Nanog、OCT4和SOX2 mRNA的表达;CCK-8法检测细胞增殖;台盼蓝染色检测细胞存活能力;茜素红S染色和油红O染色分别检测两组干细胞的成骨和成脂分化;免疫荧光检测两组细胞成神经分化相关因子DCX和NSE的表达.结果:与对照组相比,rhMG53组BMSCs的Nanog、OCT4和SOX2 mRNA表达无明显变化(P>0.05),但细胞增殖能力增强,存活率升高,成骨、成脂和成神经分化效率增加(P均<0.05).结论:rhMG53作为保护剂的特殊组分对冷冻保存的BMSCs有较好的保护效果.

Long non-coding RNAs (lncRNAs) are defined as non-coding transcripts (>200 nucleotides) that serve important roles in the proliferation and differentiation of stem cells. Hair follicle stem cells (HFTs) have multidirectional differentiation potential and are able to differentiate into skin, hair follicles and sebaceous glands, serving a role in skin wound healing. The aim of the present study was to analyze the regulatory role of lncRNA AK015322 (IncRNA5322) in HFTs and the potential mechanism of IncRNA5322‑mediated differentiation of HFTs. The results demonstrated that lncRNA5322 transfection promoted proliferation and differentiation in HFTs. It was identified that lncRNA5322 transfection upregulated the expression and phosphorylation of phosphoinositide 3‑kinase (PI3K) and protein kinase B (AKT) in HFTs. It was also observed that lncRNA5322 transfection upregulated microRNA (miR)‑21 and miR‑21 agonist (agomir‑21) eliminated lncRNA5322‑induced expression and phosphorylation of PI3K and AKT. The present study also demonstrated that agomir‑21 blocked IncRNA5322‑induced expression and phosphorylation of PI3K and AKT in HFTs. The results indicated that agomir‑21 transfection also suppressed the IncRNA5322‑induced proliferation and differentiation of HFTs. In conclusion, the results of the present study suggest that lncRNA5322 is able to promote the proliferation and differentiation of HFTs by targeting the miR‑21‑mediated PI3K‑AKT signaling pathway in HFTs.

BACKGROUND: Umbilical cord mesenchymal stem cells (UC-MSCs) are a group of cells that have self-renewal, highly proliferative and multidrug differentiation potential. The properties of UC-MSCs and their tumor tropism make them an ideal tool for glioma cell therapy. These cells can act by paracrine or as a delivery system for genes and drugs. It has been demonstrated that UC-MSCs can inhibit the growth of glioma and improve the survival after transplantation into the brain. OBJECTIVE: To summarize the molecular mechanisms and safety of UC-MSCs in the treatment of glioma and to provide a useful reference for further research. METHODS: We searched the PubMed and CNKI databases from 2000 to 2017 with the English terms of "glioma; umbilical cord mesenchymal stem cells" and the Chinese terms of "glioma; umbilical cord mesenchymal stem cells; safety; molecular mechanism". Based on the inclusion and exclusion criteria, 55 articles were finally reserved for review. RESULTS AND CONCLUSION: UC-MSCs have obvious effect on treating glioma. These cells can treat glioma through homing mechanism and paracrine mechanism as gene carrier and co-culture. Moreover, UC-MSCs have certain safety in the treatment of glioma.

Mesenchymal stem cell transplantation is a promising therapeutic approach for Alzheimer’s disease (AD). However, poor engraftment and limited survival rates are major obstacles for its clinical application. Resveratrol, an activator of silent information regulator 2, homolog 1 (SIRT1), regulates cell destiny and is beneficial for neurodegenerative disorders. The present study is designed to explore whether resveratrol regulates the fate of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) and whether hUC-MSCs combined with resveratrol would be efficacious in the treatment of neurodegeneration in a mouse model of AD through SIRT1 signaling. Herein, we report that resveratrol facilitates hUC-MSCs engraftment in the hippocampus of AD mice and resveratrol enhances the therapeutic effects of hUC-MSCs in this model as demonstrated by improved learning and memory in the Morris water maze, enhanced neurogenesis and alleviated neural apoptosis in the hippocampus of the AD mice. Moreover, hUC-MSCs and resveratrol jointly regulate expression of hippocampal SIRT1, PCNA, p53, ac-p53, p21, and p16. These data strongly suggests that hUC-MSCs transplantation combined with resveratrol may be an effective therapy for AD.

In the past few decades, there have been potential applications for stem cell replacement therapy in the treatment of nervous system damage resulting from diseases or traumatic brain injury (TBI). However, the insufficient number of transplanted stem cells and low survival rate caused by a series of negative conditions limit the therapeutic effect. In this contribution, we developed an injectable hydrogel composed of sodium alginate (SA) and hyaluronic acid (HA) as a tissue scaffold to create a more optimal microenvironment for stem cells after implantation. The gelation time of the HA/SA hydrogel exceeded 6 min, which satisfied the requirements for injection performance, and the high ratios of water content and slower degradation speed affirmed that the HA/SA hydrogel is a preferable stem cell scaffold. As a tissue engineering scaffold, the HA/SA hydrogel exhibited appropriately porous structures for stem cell loading and good rheological behavior, which contributed to stem cell differentiation. The in vitro culture experiment proved that the HA/SA scaffold performed well on hUC-MSCs with higher viability ratio and proliferation. Further in vivo tests indicated that the HA/SA scaffold not only protected the injected human umbilical cord mesenchymal stem cells (hUC-MSCs) so that they could maintain a higher survival ratio, but it also contributed to the regeneration of endogenous nerve cells. In summary, this injectable HA/SA hydrogel has the potential to be used for stem cell tissue engineering and support the physiological function recovery of TBI patients.

Aim:To investigate the neuroprotective effect of human umbilical cord mesenchymal stem cells (hUC-MSCs) transplantation with 30 nmol/L trichostatin A(TSA) pretreatment in a mice model of traumatic brain injury(TBI).Methods: TBI models were produced by using the head hit,and the 27 mice were randomly allocated into vehicle group,MSCs transplantation group and TSA combined with MSCs transplantation group.After 3 days,PI staining was used to analyze the neuron cell necrosis around the injured site.NDS system and Sucrose preference test were used to evaluate sensory function of mouse nerve and the depression of mice on the 1st,2nd,3rd,7th,14th,21st,and 28th day.The relative expression levels of HDAC1,DCX and MAP2 were detected by qRT-PCR.Results: On the 3rd day after operation,compared with Veh group,the number of necrosis cells in MSCs transplantation group and TSA+MSCs transplantation group were significantly reduced,especially the latter group(P<0.001).There was no significant difference in NDS score among the 3 groups in the 1st day.On 3rd day after operation,the NDS score of TSA+MSCs transplantation group was significantly lower than those of MSCs transplantation group and Veh group(P<0.001).On the 28th day after operation,compared with the other 2 groups,the degree of sucrose preference in the 28 day after surgery was increased,HDAC1 expression was reduced,and the expressions of DCX and MAP2 in TSA+MSCs transplantation were enhanced(P<0.001).Conclusion: TSA pretreatment could effectively improve the nerve repairment of hUC-MSCs transplantation in TBI mice.

Accumulating evidence suggests that oxidative stress induced by beta-amyloid (Aβ) is implicated in the pathlogical progression of Alzheimer’s disease (AD). 3H-1,2-dithiole-3-thione (D3T), the simplest compound of the sulfur-containing dithiolethiones, has been proved to be a strongly active antioxidant factor by regulation of the nuclear factor E2-related factor 2 (Nrf2). Previous study reported that D3T confers protection to AD cell model in vitro, however, the neuroprotective effect of D3T in the AD mammalian model is unknown. In the present study, we aimed to evaluate the therapeutic potential of D3T in the Tg2576 AD mouse model and investigate the mechanisms underlying its beneficial effects. We showed that intraperitoneal administration of D3T significantly alleviated cognitive deficits in AD mice and dramatically decreased insoluble Aβ level and oxidative stress. Further mechanistic studies revealed that D3T significantly promoted hippocampal neurogenesis, and up-regulated levels of silent information regulator 1 (Sirt1), Nrf2 and heme oxygenase-1 (HO-1). Moreover, the positive effect of D3T on behavioral performance of AD mice was markedly attenuated by inhibition of the Sirt1/Nrf2 pathway by the antagonist EX527. In summary, our studies on a mouse AD model indicate that D3T could serve as a potential therapeutic agent for this devastating disease.

Aim: To investigate the protective effects of recombinant human MG 53 ( rhMG53 ) protein on the mouse model of traumatic brain injury (TBI).Methods:A weight drop model was used to establish the mouse model of TBI ,and model mice were randomly allocated into TBI group and rhMG 53 treated group ( TBI +MG53 group ) , 21 mice in each group.On the 1st, 3ed, 7th, 14th, 21th, 28th day, the body weight was detected ,at the same time mNSS score was used to observe the neurological deficits;on the 3ed day, Western blot was used to detect the expression of MG 53 in brain tis-sue, dry wet weight method , to detect the content of brain water and ELISA , for detection of serum SOD and MDA content;After 27 or 28 days, the depression and cognitive function of mice were detected by forced swimming test and new thing rec -ognition experiment , CV staining was used to observe the brain damage of the two groups and qRT-PCR, to analyze the ex-pression of neurotrophic factor (BDNF and NGF) expression in brain tissue of each group .Results:rhMG53 could migrate and distribute in the area of brain injury; compared with the TBI group , injection of rhMG53 could increase the body weight, reduce the neurological deficit , alleviate depression and improve cognitive function of TBI mice ( P<0.05); rh-MG53 could increase the expression of SOD in serum and decrease the content of MDA (P<0.05),and reduce brain water content and the damage volume, increase mRNA expression of BDNF and NGF in the injury site (P<0.05).Conclusion:Exogenous rhMG 53 protein has a significant protective effect on TBI mice.

创伤性颅脑损伤(traumatic brain injury,TBI)是发生在中枢神经系统的一种常见疾病.近年来人脐带间充质干细胞(human umbilical cord mesenchymal stem cells,hUC-MSCs)移植为其治疗提供了新思路.间充质干细胞(mesenchymal stem cells,MSCs)能优先归巢到受损组织,分泌多种因子从而发挥营养、保护、清理、激活和桥接作用.但是,目前干细胞移植治疗TBI的研究大部分还处于实验动物模型阶段,其在临床上的安全性和有效性仍缺乏有效证据,还需要在大宗和长期的临床试验中进行评价和验证.笔者对hUC-MSCs移植治疗TBI的研究进展情况作一综述,为其开展更为广泛的研究提供有益参考.

BRAF-activated non-coding RNA (BANCR) is a long non-coding RNA (lncRNA) that contributes to the initiation and development of many solid tumors, including melanoma. However, the BANCR functions and downstream mechanisms are largely unknown. In this study, we aim to investigate how BANCR participates in the proliferation and migration of malignant melanoma and elucidate the underlying mechanism in this process. We found that the expression of the BANCR was low in melanocytic nevus and human melanocytes but high in melanoma tissues and cell lines. Knockdown of BANCR inhibited melanoma cell proliferation and invasion, and induced cell apoptosis. The decreased expression of relative marker proteins further demonstrated the inhibitory effect of BANCR siRNA in cell growth and migration. Then, we detected downregulation of microRNA-204 (miR‑204), a suppressor of melanoma growth, in melanoma tissues and cell lines. We identified that miR‑204 was a direct target of BANCR and neurogenic locus notch homolog protein 2 (Notch2) was a direct target of miR‑204. BANCR may promote melanoma cell growth through inhibition of miR‑204, leading to the activation of Notch2 pathway. By tumorigenicity assay in BALB/c nude mice, we further demonstrated that BANCR knockdown inhibited tumor growth in vivo. Our results suggest the BANCR/miR‑204/Notch2 axis mediates melanoma cell proliferation and tumor progression.

Aim: To evaluate whether transplantation of hUC-MSCs with silenced HDAC1 could facilitate recovery of nerve function in the mice model of traumatic brain injury .Methods: Moderate traumatic brain injury mice models were made by the stereotaxic apparatus and modified weight-drop model.Eighty C57BL/6 mice were randomly allocated into four groups:Sham group, Vehicle group, hUC-MSCs group and Combination group (n=20).After brain injury, mice neurological function was evaluated by the modified neurological severity score on the 1st, 3rd, 7th, 14th, 21st and 28th day.The indexes of motor function and cognitive function were evaluated via the Morris water maze test , the tail suspension test and the novel object recognition , respectively .The size of cortical lesion and the morphological changes of neurons in hippocampal CA 3 area were detected by crystal violet staining .Brain water content was measured with wet-dry weight formula .Blood brain barrier permeability was measured by Evans blue staining .Results:Compared with Vehicle group , the modified neurological severi-ty scores significantly decreased in hUC-MSCs group and Combination group , the escape latency distinctly reduced accompa-nied with a sharp increase in both the times of crossing the plat and the time in target quadrant , time of wire hanging and dis-crimination index were increased, especially in Combination group(P<0.05).The evaluating indexes in Combination group such as brain damage volume , brain water content ,localized opening blood brain barrier and the loss of neurons in the hipp-ocampal CA3 area were appreciably reduced (P<0.05).Conclusion:Transplantation of hUC-MSCs with HDAC1 deficiency could provide a better neuroprotection in traumatic brain injury mice .