Long noncoding RNA LBX2-AS1 promotes colorectal cancer progression via binding with PTBP1 and stabilizing KAT2A expression.

The long noncoding RNAs (lncRNAs) have been investigated in colorectal cancer (CRC). The aim of this study is to identify the biological functions of LBX2-AS1 in CRC. Quantitative real-time polymerase chain reaction was used to examine the expression of LBX2-AS1 in CRC cells. Cell counting kit-8 and colony formation assays were performed to examine cell proliferation. Wound healing and transwell invasion assays were performed to examine the cell migration and invasion. The interaction between PTBP1 and LBX2-AS1 or KAT2A was confirmed by RNA immunoprecipitation. The KAT2A messenger RNA (mRNA) stability was probed using the transcriptional inhibitor Actinomycin D. LBX2-AS1 was significantly increased in CRC tissues and cells. Knockdown of LBX2-AS1 inhibited CRC cell proliferation, migration, and invasion. The notch signaling pathway was activated by LBX2-AS1. LBX2-AS1 enhanced the mRNA stability of the histone acetyltransferase KAT2A by interacting with RNA-binding protein PTBP1. LBX2-AS1 acted as an oncogene in CRC.

Sorafenib not only impairs endothelium-dependent relaxation but also promotes vasoconstriction through the upregulation of vasoconstrictive endothelin type B receptors.

As a VEGF-targeting agent, sorafenib has been used to treat a number of solid tumors but can easily lead to adverse vascular effects. To elucidate the underlying mechanism, rat mesenteric arteries were subjected to organ cultured in the presence of different concentrations of sorafenib (0, 3, 6 and 9 mg/L) with or without inhibitors (U0126, 10-5 M; SB203580, 10-5 M; SP200126, 10-5 M) of MAPK kinases, and then acetylcholine- or sodium nitroprusside-induced vasodilation and sarafotoxin 6c-induced vasoconstriction were monitored by a sensitive myograph. The NO synthetases, the nitrite levels, the endothelial marker CD31,the ETB and ETA receptors and the phosphorylation of MAPK kinases were studied. Next, rats were orally administrated by sorafenib for 4 weeks (7.5 and 15 mg/kg/day), and their blood pressure, plasma ET-1, the ETB and ETA receptors and the phosphorylation of MAPK kinases in the mesenteric arteries were investigated. The results showed that sorafenib impairs endothelium-dependent vasodilation due to decreased NO levels and the low expression of eNOS and iNOS. Weak staining for CD31 indicated that sorafenib induced endothelial damage. Moreover, sorafenib caused the upregulation of vasoconstrictive ETB receptors, the enhancement of ETB receptor-mediated vasoconstriction and the activation of JNK/MAPK. Blocking the JNK, ERK1/2 and p38/MAPK signaling pathways by using the inhibitors significantly abolished ETB receptor-mediated vasoconstriction. Furthermore, it was observed that the oral administration of sorafenib caused an increase in blood pressure and plasma ET-1, upregulation of the ETB receptor and the activation of JNK in the mesenteric arteries. In conclusion, sorafenib not only impairs endothelium-dependent vasodilatation but also enhances ETB receptor-mediated vasoconstriction, which may be the causal factors for hypertension and other adverse vascular effects in patients treated with sorafenib.

Long-term toxicological studies on the Chinese medicine 2036 Specialty-Qiangxin recipe in rats.

CONTEXT: The traditional medicine 2036 Specialty-Qiangxin recipe (2036S-QXR) has been widely used in China to improve cardiac function, prevent stroke, and strengthen the immune system. However, its long-term toxicity remains unknown. OBJECTIVE: The present study evaluates the long-term toxicity of 2036S-QXR in rats. MATERIALS AND METHODS: 2036S-QXR (0.6, 1.2, and 2.4 g/kg body weight per day) was orally administered for 26 weeks to Wistar rats, while the rats in the control group received distilled water. The effects on urinary, hematological, biochemical, and histopathological parameters were investigated during the study period. RESULTS: No significant changes in all tested parameters were observed in the 0.6 and 1.2 g/kg groups, compared with the control group (p < 0.05). Higher levels of alanine aminotransferase (46.00 ± 12.85 vs. 25.40 ± 3.36) and aspartate aminotransferase (152.40 ± 32.52 vs. 111.40 ± 18.78) were observed after 13 weeks in the female rats in the 2.4 g/kg group compared with the control group (p < 0.05), but these returned to the control levels after the recovery period (p > 0.05). Several cases displayed the presence of urine protein (3/7 males and 3/7 females) and mild lesions in the kidney (10/20) and thymus (5/20) in the 2.4 g/kg group, without significant changes compared with the control group (p > 0.05). DISCUSSION AND CONCLUSIONS: The present study shows that 2036S-QXR does not cause long-term toxicity, supporting its therapeutic use. To further determine the optimal doses, future studies should test more doses and include more animals in each group.

Chiral metallohelices enantioselectively target hybrid human telomeric G-quadruplex DNA.

The design and synthesis of metal complexes that can specifically target DNA secondary structure has attracted considerable attention. Chiral metallosupramolecular complexes (e.g. helicates) in particular display unique DNA-binding behavior, however until recently few examples which are both water-compatible and enantiomerically pure have been reported. Herein we report that one metallohelix enantiomer Δ1a, available from a diastereoselective synthesis with no need for resolution, can enantioselectively stabilize human telomeric hybrid G-quadruplex and strongly inhibit telomerase activity with IC50 of 600 nM. In contrast, no such a preference is observed for the mirror image complex Λ1a. More intriguingly, neither of the two enantiomers binds specifically to human telomeric antiparallel G-quadruplex. To the best of our knowledge, this is the first example of one pair of enantiomers with contrasting selectivity for human telomeric hybrid G-quadruplex. Further studies show that Δ1a can discriminate human telomeric G-quadruplex from other telomeric G-quadruplexes.

Blockade of IL-17A/IL-17R Pathway Protected Mice from Sepsis-Associated Encephalopathy by Inhibition of Microglia Activation.

Sepsis-associated encephalopathy (SAE) is a poorly understood condition that leads to long-term cognitive impairment and increased mortality in survivors. Recent research revealed that IL-17A/IL-17R might serve as a checkpoint in microglia-mediated neuroinflammation. The present study was designed to determine the specific role of IL-17A-mediated microglia activation in the development of SAE. A mouse model of SAE was induced by cecal ligation and puncture (CLP), and behavior performance was evaluated by the inhibitory avoidance test and the open field test. Cytokine expression and microglia activation in brain tissue were determined at 6 h, 12 h, 24 h, 48 h, and day 7 post surgery. Further, septic mice were intracerebral ventricle- (i.c.v.-) injected with recombinant IL-17A, anti-IL-17A ab, anti-IL-17R ab, or isotype controls to evaluate the potential effects of IL-17A/IL-17R blockade in the prevention of SAE. Septic peritonitis induced significant impairment of learning memory and exploratory activity, which was associated with a higher expression of IL-17A, IL-1ß, and TNF-α in the brain homogenate. Fluorescence intensity of Iba-1 and IL-17R in the hippocampus was significantly increased following CLP. Treatment with recombinant IL-17A enhanced the neuroinflammation and microglia activation in CLP mice. On the contrary, neutralizing anti-IL-17A or anti-IL-17R antibodies mitigated the CNS inflammation and microglia activation, thus alleviating the cognitive dysfunction. Furthermore, as compared to the sham control, microglia cultured from CLP mice produced significantly higher levels of cytokines and expressed with higher fluorescence intensity of Iba-1 in response to IL-17A or LPS. Pretreatment with anti-IL-17R ab suppressed the Iba-1 expression and cytokine production in microglia stimulated by IL-17A. In conclusion, blockade of the IL-17A/IL-17R pathway inhibited microglia activation and neuroinflammation, thereby partially reversing sepsis-induced cognitive impairment. The present study suggested that the IL-17A/IL-17R signaling pathway had an important, nonredundant role in the development of SAE.

Small molecules for reprogramming and transdifferentiation.

Pluripotency reprogramming and transdifferentiation induced by transcription factors can generate induced pluripotent stem cells, adult stem cells or specialized cells. However, the induction efficiency and the reintroduction of exogenous genes limit their translation into clinical applications. Small molecules that target signaling pathways, epigenetic modifications, or metabolic processes can regulate cell development, cell fate, and function. In the recent decade, small molecules have been widely used in reprogramming and transdifferentiation fields, which can promote the induction efficiency, replace exogenous genes, or even induce cell fate conversion alone. Small molecules are expected as novel approaches to generate new cells from somatic cells in vitro and in vivo. Here, we will discuss the recent progress, new insights, and future challenges about the use of small molecules in cell fate conversion.

Mirror-Image Dependence: Targeting Enantiomeric G-Quadruplex DNA Using Triplex Metallohelices.

Natural d-DNA and l-DNA are mirror-image counterparts. However, because of the inherent flexibility and conformation diversity of DNA, it is still not clear how enantiomeric compounds recognize d-DNA and l-DNA. Herein, taking G-quadruplex (G4) DNA as an example that has diverse conformations and distinct biofunctions, the binding of ten pairs of iron triplex metallohelices to d- and l-G4 DNA were evaluated. The Δ-enantiomer binds to d-DNA and the Λ-enantiomer binds to l-DNA, exhibiting almost the same stabilization effect and binding affinity. The binding affinity of the Δ-metallohelix with d-G4 is nearly 70-fold higher than that of Λ-metallohelix binding d-G4. Δ-Metallohelix binding to d-G4 follows a two-step binding process driven by a favorable enthalpy contribution to compensate for the associated unfavorable entropy.

New insights in amyloid beta interactions with human telomerase.

It is well-known that aging is the most risk factor for Alzheimer's disease (AD). Recent studies have demonstrated that human telomerase is associated with pathological mechanisms of AD. In view of the central role of telomere and telomerase in the aging process, herein we found that the aggregated form Aß (Aß1-40 and Aß1-42), not Aß monomer, could inhibit telomerase activity both in vitro and in living cells. The ß-sheet structures were essential for Aß-induced telomerase inhibition. Further studies indicated Aß oligomers inhibited telomerase activity through binding to DNA·RNA hybrid formed by telomeric DNA and the RNA template of telomerase, then blocking telomerase elongation of telomeric DNA. We also identified that intracellular Aß localized at telomere, and induced cell senescence and telomere shortening. These results indicate that Aß oligomers can be potential natural inhibitors of telomerase and that inhibition of telomerase activity may be one of the factors for Aß-induced cytotoxicity. Our work may offer a new clue to a better understanding of aging and AD.

Lighting up left-handed Z-DNA: photoluminescent carbon dots induce DNA B to Z transition and perform DNA logic operations.

Left-handed Z-DNA has been identified as a transient structure occurred during transcription. DNA B-Z transition has attracted much attention because of not only Z-DNA biological importance but also their relation to disease and DNA nanotechnology. Recently, photoluminescent carbon dots, especially highly luminescent nitrogen-doped carbon dots, have attracted much attention on their applications to bioimaging and gene/drug delivery because of carbon dots with low toxicity, highly stable photoluminescence and controllable surface function. However, it is still unknown whether carbon dots can influence DNA conformation or structural transition, such as B-Z transition. Herein, based on our previous series work on DNA interactions with carbon nanotubes, we report the first example that photoluminescent carbon dots can induce right-handed B-DNA to left-handed Z-DNA under physiological salt conditions with sequence and conformation selectivity. Further studies indicate that carbon dots would bind to DNA major groove with GC preference. Inspired by carbon dots lighting up Z-DNA and DNA nanotechnology, several types of DNA logic gates have been designed and constructed based on fluorescence resonance energy transfer between photoluminescent carbon dots and DNA intercalators.

Deciphering a nanocarbon-based artificial peroxidase: chemical identification of the catalytically active and substrate-binding sites on graphene quantum dots.

The design and construction of efficient artificial enzymes is highly desirable. Recent studies have demonstrated that a series of carbon nanomaterials possess intrinsic peroxidase activity. Among them, graphene quantum dots (GQDs) have a high enzymatic activity. However, the catalytic mechanism remains unclear. Therefore, in this report, we chose to decipher their peroxidase activity. By selectively deactivating the ketonic carbonyl, carboxylic, or hydroxy groups and investigating the catalytic activities of these GQD derivatives, we obtained evidence that the -C=O groups were the catalytically active sites, whereas the O=C-O- groups acted as substrate-binding sites, and -C-OH groups can inhibit the activity. These results were corroborated by theoretical studies. This work should not only enhance our understanding of nanocarbon-based artificial enzymes, but also facilitate the design and construction of other types of target-specific artificial enzymes.

Substance basis and pharmacological mechanism of heat-clearing herbs in the treatment of ischaemic encephalopathy: a systematic review and network pharmacology.

BACKGROUND AND OBJECTIVE: Ischaemic encephalopathy is a common cerebrovascular disease caused by insufficient blood supply to the cerebral vessels. The ischaemic encephalopathy is closely associated with the development of many chronic diseases such as obesity, hypertension and diabetes. Neurotrophic therapy has become the main therapeutic strategy for ischaemic encephalopathy. However, neurotrophic drugs only slightly recover the neurological function of patients, and their long-term efficacy is uncertain. Previous reports revealed that the active ingredients of natural medicines play important roles in the treatment of cerebral ischemia. In this study, we reviewed clearing herbs with anti-ischaemic encephalopathy functions using the data from quantitative statistical and network pharmacological exploration methods. We also discussed the different bioactive components and pharmacological effects of these herbs. METHODS: First, we collected Chinese herbal prescriptions against ischaemic encephalopathy in four databases. Then, we statistically analysed the frequency of application of heat-clearing herbs to obtain the commonly used heat-clearing herbs against ischaemic encephalopathy, and classified them according to their efficacy according to the statistical results, to summarize the mechanism of anti-ischaemic effects of different bioactive components; Second, the network database was used to obtain the above components of heat-clearing Chinese medicines and their corresponding targets of action, disease targets of ischaemic stroke; Venny 2.1.0 was used to obtain component-disease target intersections; Cytoscape was used to construct the 'Drug-Active Ingredient-Target Network Graph '; DAVID was used for GO and KEGG enrichment analysis. RESULTS: Literature and database screening involved 149 prescriptions, with a total of 269 flavours of Chinese medicines and 20 flavours of single-flavour heat-clearing Chinese medicines; The top nine in terms of frequency of use were Radix Paeoniae Rubra、Rehmanniae Radix Praeparata、Figwort Root、Cortex Moutan、Scutellariae Radix、Coptidis Rhizoma、Gardeniae Fructus、Cassiae Semen、Lonicerae Japonicae Flos. The common components obtained from network pharmacology were beta-sitosterol, quercetin, and stigmasterol, which mainly act on key targets such as RELA, AKT1, JUN, PRKACA, PTGS2, RAF1 and CHUK; and their active ingredients are mainly involved in signalling pathways such as Calcium, PI3K-Ak, MAPK, cAMP, IL-17, HIF-1, TNF, T-cell receptor, NF-kappa B and JAK-STAT. CONCLUSIONS: Heat-clearing herbs are useful and promising for the protection against and prevention of ischemic encephalopathy. The results of the network pharmacological studies are similar to the mechanisms of anti-ischemic encephalopathy of the active ingredients of the purgative herbs we have listed; Thin either directly protects cerebrovascular tissues by improving vascular permeability and reducing the area of infarcted tissues, or produces protective effects through molecular signaling pathways. It can be seen that the components of heat-clearing Chinese medicines can exert cerebroprotective effects through multiple pathways, which provides us with a reference for further development and study of heat-clearing Chinese medicines in the treatment of ischemic cerebrovascular diseases.

Ionic liquid as an efficient modulator on artificial enzyme system: toward the realization of high-temperature catalytic reactions.

Herein, with the aid of ionic liquid, we demonstrate for the first time that highly stable Au/SiO2 hetero-nanocomposites can serve as a robust and recyclable peroxidase mimic for realizing high-temperature catalytic reactions. Our findings pave the way to use nanomaterials for the design and development of efficient biomimetic catalysts and, more significantly, to apply ionic liquid as a positive modulator in catalytic reactions.

The SDF-1/CXCR4 Signaling Pathway Directs the Migration of Systemically Transplanted Bone Marrow Mesenchymal Stem Cells Towards the Lesion Site in a Rat Model of Spinal Cord Injury.

BACKGROUND: It has been observed that bone marrow-derived mesenchymal stem cells (MSCs) migrate towards the injured spinal cord and promote functional recovery when systemically transplanted into the traumatized spinal cord. However, the mechanisms underlying their migration to the spinal cord remain poorly understood. METHODS: In this study, we systemically transplanted GFP- and luciferase-expressing MSCs into rat models of spinal cord injury and examined the role of the stromal cell-derived factor 1 (SDF-1)/CXCR4 axis in regulating the migration of transplanted MSCs to the spinal cord. After intravenous injection, MSCs migrated to the injured spinal cord where the expression of SDF-1 was increased. Spinal cord recruitment of MSCs was blocked by pre-incubation with an inhibitor of CXCR4. Their presence correlated with morphological and functional recovery. In vitro, SDF-1 or cerebrospinal fluid (CSF) collected from SCI rats promoted a dose-dependent migration of MSCs in culture, which was blocked by an inhibitor of CXCR4 or SDF-1 antibody. RESULTS AND CONCLUSION: The study suggests that SDF-1/CXCR4 interactions recruit exogenous MSCs to injured spinal cord tissues and may enhance neural regeneration. Modulation of the homing capacity may be instrumental in harnessing the therapeutic potential of MSCs.

An optimized method to visualize the goblet cell-associated antigen passages and identify goblet cells in the intestine, conjunctiva, and airway.

The goblet cell-associated antigen passages (GAPs), formed in the intestine and conjunctiva, contribute to immune responses by delivering antigens to immune cells. It has been proved that dysfunctions of GAPs may contribute to intestinal inflammation and dry eye disease. GAPs were first discovered in the intestine with the help of intravital two-photon microscopy. The imaging of GAPs was subsequently captured in a frozen section and whole-mount immunofluorescent staining. Both protocols have their features. This study provides a new protocol for visualizing GAPs with better mucus preservation by combining 4% PFA and methanol-Carnoy's solution (PFA-MC). In addition, embedding samples in paraffin provides an opportunity for antigen retrieval for immunohistochemistry analysis. Using this protocol, we have successfully visualized GAPs in the intestine, intestinal organoids, conjunctiva, and trachea. It is worth mentioning that the visualization of GAPs in intestinal organoids and airways has rarely been discussed before, which may assist researchers in their studies. Moreover, we also discovered the active uptake of dextran of club cells in terminal bronchioles, which may provide a new direction for studying the function of club cells. Overall, we developed a new method to visualize GAP formation and identify GCs simultaneously in the intestine, organoid, conjunctiva, and airway.

Chemical conversion of human epidermal stem cells into intestinal goblet cells for modeling mucus-microbe interaction and therapy.

Intestinal goblet cells secrete mucus layers protecting the intestinal epithelia against injuries. It is challenging to study the interaction of goblet cells, mucus layers, and gut microbiota because of difficulty in producing goblet cells and mucus models. We generate intestinal goblet cells from human epidermal stem cells with two small molecular inhibitors Repsox and CHIR99021 in the presence of basic fibroblast growth factor and bone morphogenetic protein 4 at high efficiency (~95%) of conversion for a short time (6 to 8 days). Induced goblet cells are functional to secrete mucus, deliver fluorescent antigen, and form mucus layers modeling the mucus-microbe interaction in vitro. Transplantation of induced goblet cells and oral administration of chemical induction media promote the repair of the intestinal epithelia in a colitis mouse model. Thus, induced goblet cells can be used for investigating mucus-microbe interaction, and chemical cocktails may act as drugs for repairing the intestinal epithelia.

Mesenchymal stem cell therapy for acute respiratory distress syndrome: from basic to clinics.

The 2019 novel coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has occurred in China and around the world. SARS-CoV-2-infected patients with severe pneumonia rapidly develop acute respiratory distress syndrome (ARDS) and die of multiple organ failure. Despite advances in supportive care approaches, ARDS is still associated with high mortality and morbidity. Mesenchymal stem cell (MSC)-based therapy may be an potential alternative strategy for treating ARDS by targeting the various pathophysiological events of ARDS. By releasing a variety of paracrine factors and extracellular vesicles, MSC can exert anti-inflammatory, anti-apoptotic, anti-microbial, and pro-angiogenic effects, promote bacterial and alveolar fluid clearance, disrupt the pulmonary endothelial and epithelial cell damage, eventually avoiding the lung and distal organ injuries to rescue patients with ARDS. An increasing number of experimental animal studies and early clinical studies verify the safety and efficacy of MSC therapy in ARDS. Since low cell engraftment and survival in lung limit MSC therapeutic potentials, several strategies have been developed to enhance their engraftment in the lung and their intrinsic, therapeutic properties. Here, we provide a comprehensive review of the mechanisms and optimization of MSC therapy in ARDS and highlighted the potentials and possible barriers of MSC therapy for COVID-19 patients with ARDS.

Patient-Specific Cells for Modeling and Decoding Amyotrophic Lateral Sclerosis: Advances and Challenges.

Motor neuron loss or degeneration is the typical characteristic of amyotrophic lateral sclerosis (ALS), which often leads to weakness, paralysis, or even death. The underlying mechanisms of motor neuron degeneration and ALS progression remain elusive, and there is no effective treatment for ALS. The advances of stem cells and reprogramming techniques has made it possible to generate patient-specific motor neurons as cell models for studying disease mechanisms and drug discovery. This review comprehensively discusses recent approaches to generate motor neurons from stem cells and somatic cells and highlights the application of induced motor neurons to modeling ALS diseases, dissecting the pathogenesis, and screening new drugs. New perspectives are also discussed on generating patient-specific motor neuron subtypes that are affected by ALS or creating 3D spinal cord organoid models for better recapitulating and understanding ALS.

Generation of keratinocyte stem-like cells from human fibroblasts via a direct reprogramming approach.

Skin repair and reconstruction are important after severe wound and trauma. Keratinocyte stem cells (KSCs) in the basal layer of the epidermis can regrow the stratified epidermis but are almost depleted after skin injury. Thus, generating enough KSCs is indispensable for skin regeneration. Pluripotent stem cells such as ESC and iPSC can differentiate into KSCs, but their applications are challenged by ethical issues and risks of tumor formation. Lineage reprogramming from one cell type into another one makes it feasible to generate the desired cell type. Here, we develop a method to convert human fibroblasts into induced keratinocyte stem-like cells (iKSC) by coupling transient expression of reprogramming factors with a chemically defined culture medium, without the formation of iPSC. iKSC resemble normal KSC in the morphological and phenotypic features and can differentiate in vitro and regenerate stratified epidermis after transplantation in vivo. Therefore, iKSC may provide abundant cellular sources for skin repair and regeneration.

Direct conversion of human fibroblasts into dopaminergic neuron-like cells using small molecules and protein factors.

BACKGROUND: Generation of neurons is essential in cell replacement therapy for neurodegenerative disorders like Parkinson's disease. Several studies have reported the generation of dopaminergic (DA) neurons from mouse and human fibroblasts by ectopic expression of transcription factors, in which genetic manipulation is associated with potential risks. METHODS: The small molecules and protein factors were selected based on their function to directly induce human fetal lung IMR-90 fibroblasts into DA neuron-like cells. Microscopical, immunocytochemical, and RT-qPCR analyses were used to characterize the morphology, phenotype, and gene expression features of the induced cells. The whole-cell patch-clamp recordings were exploited to measure the electrophysiological properties. RESULTS: Human IMR-90 fibroblasts were rapidly converted into DA neuron-like cells after the chemical induction using small molecules and protein factors, with a yield of approximately 95% positive TUJ1-positive cells. The induced DA neuron-like cells were immunopositive for pan-neuronal markers MAP2, NEUN, and Synapsin 1 and DA markers TH, DDC, DAT, and NURR1. The chemical induction process did not involve a neural progenitor/stem cell intermediate stage. The induced neurons could fire single action potentials, which reflected partially the electrophysiological properties of neurons. CONCLUSION: We developed a chemical cocktail of small molecules and protein factors to convert human fibroblasts into DA neuron-like cells without passing through a neural progenitor/stem cell intermediate stage. The induced DA neuron-like cells from human fibroblasts might provide a cellular source for cell-based therapy of Parkinson's disease in the future.

Efficient and rapid conversion of human astrocytes and ALS mouse model spinal cord astrocytes into motor neuron-like cells by defined small molecules.

BACKGROUND: Motor neuron degeneration or loss in the spinal cord is the characteristic phenotype of motor neuron diseases or spinal cord injuries. Being proliferative and located near neurons, astrocytes are considered ideal cell sources for regenerating neurons. METHODS: We selected and tested different combinations of the small molecules for inducing the conversion of human and mouse astrocytes into neurons. Microscopic imaging and immunocytochemistry analyses were used to characterize the morphology and phenotype of the induced neurons while RT-qPCR was utilized to analyze changes in gene expression. In addition, whole-cell patch-clamp recordings were measured to examine the electrophysiological properties of induced neurons. RESULTS: The results showed that human astrocytes could be rapidly and efficiently converted into motor neuron-like cells by treatment with defined small molecules, with a yield of over 85% motor neuron-like cells attained. The induced motor neuron-like cells expressed the pan-neuronal markers TUJ1, MAP2, NeuN, and Synapsin 1 and motor neuron markers HB9, ISL1, CHAT, and VAChT. During the conversion process, the cells did not pass through a proliferative neural progenitor cell intermediate. The induced motor neurons were functional, showing the electrophysiological properties of neurons. The same chemical cocktail could induce spinal cord astrocytes from an amyotrophic lateral sclerosis mouse model carrying a SOD1 mutation to become motor neuron-like cells that exhibited a decrease in cell survival and an increase in oxidative stress compared to that observed in wild-type MNs derived from healthy mice. Moreover, the chemical induction reduced oxidative stress in the mutant astrocytes. CONCLUSION: The results of the present study demonstrated the feasibility of chemically converting human and mouse astrocytes into motor neuron-like cells that are useful for neurodegenerative disease modeling and regenerative medicine.