KDM2B and its peptides promote the stem cells from apical papilla mediated nerve injury repair in rats by intervening EZH2 function.

How to improve the neurogenic potential of mesenchymal stem cells (MSCs) and develop biological agent based on the underlying epigenetic mechanism remains a challenge. Here, we investigated the effect of histone demethylase Lysine (K)-specific demethylase 2B (KDM2B) on neurogenic differentiation and nerve injury repair by using MSCs from dental apical papilla (SCAP). We found that KDM2B promoted the neurogenic indicators expression and neural spheres formation in SCAP, and modified the Histone H3K4 trimethylation (H3K4me3) methylation on neurogenesis-related genes. KDM2B improved the SCAP mediated recovery of motor ability at the early healing stage of spinal cord injury rats. Meanwhile, KDM2B acted as a negative regulator to its partner EZH2 during neurogenic differentiation, enhancer of zeste homologue 2 (EZH2) suppressed the neurogenic ability of SCAP. Further, the protein interaction between KDM2B and EZH2 was identified which decreased during neurogenic differentiation. On this basis, we revealed seven key protein binding sequences of KDM2B to EZH2, and synthesized KDM2B-peptides based on these sequences. By the usage of KDM2B-peptides, EZH2 function was effectively intervened and the neurogenic ability of SCAP was promoted. More, KDM2B-peptides significantly improved the SCAP mediated functional recovery at SCI early phase. Our study revealed that KDM2B acted as a promotor to neurogenic differentiation ability of dental MSCs through binding and negatively regulating EZH2, and provided the KDM2B-peptides as candidate agents for improving the neurogenic ability of MSCs and nerve injury repair.

Insulin-Like Growth Factor-Binding Protein 5 Promotes the Cell Proliferation and Osteogenic Potential of Dental Pulp Stem Cells Dependent on Its Nuclear Localisation Sequence.

OBJECTIVES: Dental pulp stem cells (DPSCs) have been extensively used for tissue regeneration owing to their notable capabilities. Insulin-like growth factor-binding protein 5 (IGFBP5) regulates osteogenic differentiation of mesenchymal stem cells (MSCs); however, the underlying regulatory mechanisms require further investigation. MATERIALS AND METHODS: Carboxyfluorescein succinimidyl ester, an alkaline phosphatase (ALP) activity assay and Alizarin Red staining were used to reveal the role of IGFBP5 in DPSCs. Protein expression levels were determined using western blotting. Immunofluorescence was used to observe cell sub-localisation. Subcutaneous transplantation in nude mice was used to observe the osteogenesis of DPSCs in vivo. RESULTS: IGFBP5 enhanced the proliferation and osteogenic differentiation of DPSCs. Deletion of the nuclear localisation sequence (NLS) of IGFBP5 prevented its nuclear import and abolished all its promoting effects on DPSCs; ivermectin stimulation attenuated the enhancement of ALP activity by IGBFP5. Bone-like tissue formation promoted by IGFBP5 in vivo vanishes when the NLS is deleted. Inhibition of IGFBP5 nuclear import attenuated the IGFBP5-induced phosphorylation of JNK (p-JNK) and phosphorylated ERK (p-ERK) in DPSCs. CONCLUSION: Our findings suggest that cell proliferation and osteogenic differentiation effects exerted by IGFBP5 on DPSCs are closely associated with their entry into the nucleus, thereby providing a novel potential target for tissue regeneration.

M2DC: A Meta-Learning Framework for Generalizable Diagnostic Classification of Major Depressive Disorder.

Psychiatric diseases are bringing heavy burdens for both individual health and social stability. The accurate and timely diagnosis of the diseases is essential for effective treatment and intervention. Thanks to the rapid development of brain imaging technology and machine learning algorithms, diagnostic classification of psychiatric diseases can be achieved based on brain images. However, due to divergences in scanning machines or parameters, the generalization capability of diagnostic classification models has always been an issue. We propose Meta-learning with Meta batch normalization and Distance Constraint (M2DC) for training diagnostic classification models. The framework can simulate the train-test domain shift situation and promote intra-class cohesion, as well as inter-class separation, which can lead to clearer classification margins and more generalizable models. To better encode dynamic brain graphs, we propose a concatenated spatiotemporal attention graph isomorphism network (CSTAGIN) as the backbone. The network is trained for the diagnostic classification of major depressive disorder (MDD) based on multi-site brain graphs. Extensive experiments on brain images from over 3261 subjects show that models trained by M2DC achieve the best performance on cross-site diagnostic classification tasks compared to various contemporary domain generalization methods and SOTA studies. The proposed M2DC is by far the first framework for multi-source closed-set domain generalizable training of diagnostic classification models for MDD and the trained models can be applied to reliable auxiliary diagnosis on novel data.

NQO1 promotes osteogenesis and suppresses angiogenesis in DPSCs via MAPK pathway modulation.

BACKGROUND: Influence on stem cells' angiogenesis and osteogenesis of NAD(P)H Quinone Dehydrogenase 1(NQO1) has been established, but its impact on dental pulp stem cells (DPSCs) is unexplored. An important strategy for the treatment of arteriosclerosis is to inhibit calcium deposition and to promote vascular repair and angiogenesis. This study investigated the function and mechanism of NQO1 on angiogenesis and osteogenesis of DPSCs, so as to provide a new ideal for the treatment of arteriosclerosis. METHODS: Co-culture of human DPSCs and human umbilical vein endothelial cells (HUVECs) was used to detect the angiogenesis ability. Alkaline phosphatase (ALP) activity, alizarin red staining (ARS), and transplantation of HA/tricalcium phosphate with DPSCs were used to detect osteogenesis. RESULTS: NQO1 suppressed in vitro tubule formation, migration, chemotaxis, and in vivo angiogenesis, as evidenced by reduced CD31 expression. It also enhanced ALP activity, ARS, DSPP expression and osteogenesis and boosted mitochondrial function in DPSCs. CoQ10, an electron transport chain activator, counteracted the effects of NQO1 knockdown on these processes. Additionally, NQO1 downregulated MAPK signaling, which was reversed by CoQ10 supplementation in DPSCs-NQO1sh. CONCLUSIONS: NQO1 inhibited angiogenesis and promoted the osteogenesis of DPSCs by suppressing MAPK signaling pathways and enhancing mitochondrial respiration.

Intragland Expression of the Shh Gene Alleviates Irradiation-Induced Salivary Gland Injury through Microvessel Protection and the Regulation of Oxidative Stress.

Radiation-induced salivary gland injury (RISGI) is a common complication of radiotherapy in patients with head and neck cancer. Intragland expression of the Sonic Hedgehog (Shh) gene may partially rescue irradiation (IR)-induced hyposalivation by preserving salivary stem/progenitor cells and parasympathetic innervation, maintaining resident macrophages, and maintaining microvascular density. Previous studies have revealed that Ad-Rat Shh transduction through the salivary glands of miniature pigs can ameliorate oxidative stress-induced microvascular dysfunction after radiotherapy. Changes in the parotid salivary flow rate were analyzed, and the parotid tissue was collected at 5 and 20 weeks after IR. Changes in the Hedgehog pathway and vascular function-related markers (vascular endothelial growth factor (VEGF) and CD31) and oxidative stress-related markers were detected via immunohistochemistry, immunofluorescence, and Western blotting. A stable Shh-overexpressing cell line was generated from human umbilical vein endothelial cells (HUVECs) and exposed to 10 Gy X-ray irradiation, after which endothelial cell proliferation, senescence, apoptosis, and vascular function were evaluated. We found that intragland expression of the Shh gene efficiently alleviated IR-induced parotid gland injury in a miniature pig model. Our results indicate that the antioxidative stress and microvascular-protective effects of the Hh pathway are regulated by nuclear factor-erythroid 2-related factor 2 (Nrf2).

Experimental Research on Shipborne SINS Rapid Mooring Alignment with Variance-Constraint Kalman Filter and GNSS Position Updates.

Analytical coarse alignment and Kalman filter fine alignment based on zero-velocity are typically used to obtain initial attitude for inertial navigation systems (SINS) on a static base. However, in the shipboard mooring state, the static observation condition is corrupted. This paper presents a rapid alignment method for SINS on swaying bases. The proposed method begins with a coarse alignment technique in the inertial frame to obtain an initial rough attitude. Subsequently, a Kalman filter with position updates is employed to estimate the remaining misalignment error. To enhance the filter estimation performance, an appropriate lower boundary is set to the target states' variances according to a carefully designed relative convergence index. The variance-constraint Kalman filter (VCKF) approach is proposed in this paper, and the shipborne experiments validate its effectiveness. The results demonstrate that the VCKF approach significantly reduces the time requirement for fine alignment to achieve the same accuracy on a swaying base, from 90 min in the classic Kalman filter to 30 min. Additionally, the parameter estimation performance in the Kalman filter is also improved, particularly in situations where unpredicted external interference is involved during fine alignment.

STL Inhibited Angiogenesis of DPSCs Through Depressing Mitochondrial Respiration by Enhancing RNF217.

Angiogenesis is the determining factor during dental pulp regeneration. Six-twelve leukemia (STL) is identified as a key regulatory factor on the biological function of dental pulp stem cells (DPSCs) under hypoxic conditions, but its effect on angiogenesis is unclear. Co-culture of DPSCs and human umbilical vein endothelial cells (HUVECs) is used to detect tubule formation ability in vitro and the angiogenesis ability in vivo. RNA-seq and bioinformatic analyses are performed to screen differentially expressed genes. Seahorse Cell Mito Stress Test is proceeded to exam mitochondrial respiration. STL decreased tubule formation and mitochondrial respiration of DPSCs in vitro and restrained the number of blood vessels and the expression of VEGF in new formed tissue in vivo. Furthermore, pretreating STL-depleted DPSCs with rotenone, a mitochondrial respiration inhibitor, counteracted the promoting effect of STL knockdown on tubule formation. Then, RNA-seq and bioinformatic analyses identified some angiogenesis relevant genes and pathways in STL-depleted DPSCs. And STL enhanced expression of mRNA-ring finger protein 217 (RNF217), which inhibited the tubule formation and mitochondrial respiration of DPSCs. STL inhibited the angiogenesis of DPSCs through depressing mitochondrial respiration by enhancing RNF217, indicating that STL is a potential target for angiogenesis of DPSCs.

LncRNA SNHG1 enhances cartilage regeneration by modulating chondrogenic differentiation and angiogenesis potentials of JBMMSCs via mitochondrial function regulation.

BACKGROUND: Cartilage is a kind of avascular tissue, and it is difficult to repair itself when it is damaged. In this study, we investigated the regulation of chondrogenic differentiation and vascular formation in human jaw bone marrow mesenchymal stem cells (h-JBMMSCs) by the long-chain noncoding RNA small nucleolar RNA host gene 1 (SNHG1) during cartilage tissue regeneration. METHODS: JBMMSCs were isolated from the jaws via the adherent method. The effects of lncRNA SNHG1 on the chondrogenic differentiation of JBMMSCs in vitro were detected by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), Pellet experiment, Alcian blue staining, Masson's trichrome staining, and modified Sirius red staining. RT-qPCR, matrix gel tube formation, and coculture experiments were used to determine the effect of lncRNA SNHG1 on the angiogenesis in JBMMSCs in vitro. A model of knee cartilage defects in New Zealand rabbits and a model of subcutaneous matrix rubber suppositories in nude mice were constructed for in vivo experiments. Changes in mitochondrial function were detected via RT-qPCR, dihydroethidium (DHE) staining, MitoSOX staining, tetramethyl rhodamine methyl ester (TMRM) staining, and adenosine triphosphate (ATP) detection. Western blotting was used to detect the phosphorylation level of signal transducer and activator of transcription 3 (STAT3). RESULTS: Alcian blue staining, Masson's trichrome staining, and modified Sirius Red staining showed that lncRNA SNHG1 promoted chondrogenic differentiation. The lncRNA SNHG1 promoted angiogenesis in vitro and the formation of microvessels in vivo. The lncRNA SNHG1 promoted the repair and regeneration of rabbit knee cartilage tissue. Western blot and alcian blue staining showed that the JAK inhibitor reduced the increase of STAT3 phosphorylation level and staining deepening caused by SNHG1. Mitochondrial correlation analysis revealed that the lncRNA SNHG1 led to a decrease in reactive oxygen species (ROS) levels, an increase in mitochondrial membrane potential and an increase in ATP levels. Alcian blue staining showed that the ROS inhibitor significantly alleviated the decrease in blue fluorescence caused by SNHG1 knockdown. CONCLUSIONS: The lncRNA SNHG1 promotes chondrogenic differentiation and angiogenesis of JBMMSCs. The lncRNA SNHG1 regulates the phosphorylation of STAT3, reduces the level of ROS, regulates mitochondrial energy metabolism, and ultimately promotes cartilage regeneration.

METTL7A-mediated m6A modification of corin reverses bisphosphonates-impaired osteogenic differentiation of orofacial BMSCs.

Bisphosphonate-related osteonecrosis of jaw (BRONJ) is characterized by impaired osteogenic differentiation of orofacial bone marrow stromal cells (BMSCs). Corin has recently been demonstrated to act as a key regulator in bone development and orthopedic disorders. However, the role of corin in BRONJ-related BMSCs dysfunction remains unclarified. A m6A epitranscriptomic microarray study from our group shows that the CORIN gene is significantly upregulated and m6A hypermethylated during orofacial BMSCs osteogenic differentiation. Corin knockdown inhibits BMSCs osteogenic differentiation, whereas corin overexpression or soluble corin (sCorin) exerts a promotion effect. Furthermore, corin expression is negatively regulated by bisphosphonates (BPs). Corin overexpression or sCorin reverses BPs-impaired BMSCs differentiation ability. Mechanistically, we find altered expression of phos-ERK in corin knockdown/overexpression BMSCs and BMSCs under sCorin stimulation. PD98059 (a selective ERK inhibitor) blocks the corin-mediated promotion effect. With regard to the high methylation level of corin during osteogenic differentiation, we apply a non-selective m6A methylase inhibitor, Cycloleucine, which also blocks the corin-mediated promotion effect. Furthermore, we demonstrate that METTL7A modulates corin m6A modification and reverses BPs-impaired BMSCs function, indicating that METTL7A regulates corin expression and thus contributes to orofacial BMSCs differentiation ability. To conclude, our study reveals that corin reverses BPs-induced BMSCs dysfunction, and METTL7A-mediated corin m6A modification underlies corin promotion of osteogenic differentiation via the ERK pathway. We hope this brings new insights into future clinical treatments for BRONJ.

MiR-26b-5p/TET3 regulates the osteogenic differentiation of human bone mesenchymal stem cells and bone reconstruction in female rats with calvarial defects.

BACKGROUND: MicroRNAs (miRNAs) play critical roles in the osteogenic differentiation of human bone mesenchymal stem cells (hBMSCs), but the mechanism by which miRNAs indirectly modulate osteogenesis remains unclear. Here, we explored the mechanism by which miRNAs indirectly modulate gene expression through histone demethylases to promote bone regeneration. METHODS AND RESULTS: Bioinformatics analysis was performed on hBMSCs after 7 days of osteogenic induction. The differentially expressed miRNAs were screened, and potential target mRNAs were identified. To determine the bioactivity and stemness of hBMSCs and their potential for bone repair, we performed wound healing, Cell Counting Kit-8 (CCK-8), real-time reverse transcription quantitative polymerase chain reaction (RT‒qPCR), alkaline phosphatase activity, alizarin red S (ARS) staining and radiological and histological analyses on SD rats with calvarial bone defects. Additionally, a dual-luciferase reporter assay was utilized to investigate the interaction between miR-26b-5p and ten-eleven translocation 3 (TET3) in human embryonic kidney 293T cells. The in vitro and in vivo results suggested that miR-26b-5p effectively promoted the migration, proliferation and osteogenic differentiation of hBMSCs, as well as the bone reconstruction of calvarial defects in SD rats. Mechanistically, miR-26b-5p bound to the 3' untranslated region of TET3 mRNA to mediate gene silencing. CONCLUSIONS: MiR-26b-5p downregulated the expression of TET3 to increase the osteogenic differentiation of hBMSCs and bone repair in rat calvarial defects. MiR-26b-5p/TET3 crosstalk might be useful in large-scale critical bone defects.

Luminescence-Monitored Progressive Chemical Pressure Implementation Realized through Successive Y3+ and Mg2+ Doping into Ca10.5(PO4)7:Eu2.

Chemical pressure generated through ion doping into crystal lattices has been proven to be conducive to exploration of new matter, development of novel functionalities, and realization of unprecedented performances. However, studies are focusing on one-time doping, and there is a lack of both advanced investigations for multiple doping and sophisticated strategies to precisely and quantitatively track the gradual functionality evolution along with progressive chemical pressure implementation. Herein, high-valent Y3+ and equal-valent Mg2+ is successively doped to replace multiple Ca sites in Ca10.5(PO4)7:Eu2+. The luminescence evolution of Eu2+ serves as an optical probe, allowing step-by-step and atomic-level tracking of the site occupation of Y3+ and Mg2+, interassociation of Ca sites, and ultimately functionality improvement. The resulting Ca8MgY(PO4)7:Eu2+ displays a record-high relative sensitivity for optical thermometry. Utilization of the environment-sensitive emission of Eu2+ as a luminescent probe has offered a unique approach to monitoring structure-functionality evolution in vivo with atomic precision, which shall also be extended to optimization of other functionalities such as ferroelectricity, conductivity, thermoelectricity, and catalytic activity through precise control over atomic diffusion in other types of substances.

miR615-3p inhibited FBLN1 and osteogenic differentiation of umbilical cord mesenchymal stem cells by associated with YTHDF2 in a m6A-miRNA interaction manner.

To investigate the role and mechanism of FBLN1 in the osteogenic differentiation and bone regeneration by using umbilical cord mesenchymal stem cells (WJCMSCs). We found that FBLN1 promoted osteogenic differentiation of WJCMSCs and WJCMSC-mediated bone regeneration. It was showed that there was an m6A methylation site in 3'UTR of FBLN1 mRNA, and the mutation of the m6A site enhanced the stability of FBLN1 mRNA, subsequently fostering the FBLN1 enhanced osteogenic differentiation of WJCMSCs. YTHDF2 was identified as capable of recognizing and binding to the m6A site, consequently inducing FBLN1 instability and repressed the osteogenic differentiation of WJCMSCs. Meanwhile, miR-615-3p negatively regulated FBLN1 by binding FBLN1 3'UTR and inhibited the osteogenic differentiation of WJCMSCs and WJCMSC-mediated bone regeneration. Then, we discovered miR-615-3p was found to regulate the functions of FBLN1 facilitated by YTHDF2 through an m6A-miRNA regulation mechanism. We demonstrated that FBLN1 is critical for regulating the osteogenic differentiation potentials of WJCMSCs and have identified that miR615-3p mediated the decay of FBLN1 mRNA which facilitated by m6A reading protein YTHDF2. This provided a novel m6A-miRNA epigenetic regulatory pattern for MSC regulation and bone regeneration.

FBLN5 was Regulated by PRDM9, and Promoted Senescence and Osteogenic Differentiation of Human Periodontal Ligament Stem Cells.

OBJECTIVES: Periodontal ligament stem cells (PDLSCs) are ideal seed cells for periodontal tissue regeneration. Our previous studies have indicated that the histone methyltransferase PRDM9 plays an important role in human periodontal ligament stem cells (hPDLSCs). Whether FBLN5, which is a downstream gene of PRDM9, also has a potential impact on hPDLSCs is still unclear. METHODS: Senescence was assessed using ß-galactosidase and Enzyme-linked immunosorbent assay (ELISA). Osteogenic differentiation potential of hPDLSCs was measured through Alkaline phosphatase (ALP) activity assay and Alizarin red detection, while gene expression levels were evaluated using western blot and RT-qPCR analysis. RESULTS: FBLN5 overexpression promoted the osteogenic differentiation and senescence of hPDLSCs. FBLN5 knockdown inhibited the osteogenic differentiation and senescence of hPDLSCs. Knockdown of PRDM9 decreased the expression of FBLN5 in hPDLSCs and inhibited senescence of hPDLSCs. Additionally, both FBLN5 and PRDM9 promoted the expression of phosphorylated p38 MAPK, Erk1/2 and JNK. The p38 MAPK pathway inhibitor SB203580 and the Erk1/2 pathway inhibitor PD98059 have the same effects on inhibiting the osteogenic differentiation and senescence of hPDLSCs. The JNK pathway inhibitor SP600125 reduced the senescence of hPDLSCs. CONCLUSION: FBLN5 promoted senescence and osteogenic differentiation of hPDLSCs via activation of the MAPK signaling pathway. FBLN5 was positively targeted by PRDM9, which also activated the MAPK signaling pathway.

New insights into the interaction between m6A modification and lncRNA in cancer drug resistance.

Drug resistance is perhaps the greatest obstacle in improving outcomes for cancer patients, leading to recurrence, progression and metastasis of various cancers. Exploring the underlying mechanism worth further study. N6-methyladenosine (m6A) is the most common RNA modification found in eukaryotes, playing a vital role in RNA translation, transportation, stability, degradation, splicing and processing. Long noncoding RNA (lncRNA) refers to a group of transcripts that are longer than 200 nucleotides (nt) and typically lack the ability to code for proteins. LncRNA has been identified to play a significant role in regulating multiple aspects of tumour development and progression, including proliferation, metastasis, metabolism, and resistance to treatment. In recent years, a growing body of evidence has emerged, highlighting the crucial role of the interplay between m6A modification and lncRNA in determining the sensitivity of cancer cells to chemotherapeutic agents. In this review, we focus on the recent advancements in the interaction between m6A modification and lncRNA in the modulation of cancer drug resistance. Additionally, we aim to explore the underlying mechanisms involved in this process. The objective of this review is to provide valuable insights and suggest potential future directions for the reversal of chemoresistance in cancer.

Case Report: Genetic profiling of small intestine metastasis from poorly differentiated non-small cell lung cancer: report of 2 cases and literature review of the past 5 years.

Background: Poorly differentiated non-small cell lung cancer (NSCLC) is characteristic of high rate of distant metastasis and late stages at diagnosis. Small intestine metastasis is a rare but severe complication of lung cancer with a high rate of mortality. However, there is currently a lack of genetic profile studies on the small intestine metastasis of lung cancer. Case presentations: We present 2 cases of male patients in their 60s with primary NSCLC of low differentiation, initially with no distant metastasis detected. Biopsy samples were obtained from the primary pulmonary lesions, and both patients received systematic radiotherapy (RT) and chemotherapy. However, both cases presented with abdominal pain and distension, and immunohistochemistry of small intestine biopsy samples obtained by endoscopy confirmed lung cancer metastasis. Next generation sequencing was used to explore the genetic profiles from the biopsy samples of both the primary pulmonary lesions and small intestine metastases. The correlated genes responsible for the small intestine metastasis from poorly differentiated NSCLC in these 2 patients included TP53, LRP1B, and FGFR2. The reports of small intestine metastasis from poorly differentiated NSCLC with the past 5 years were systematically reviewed and summarized subsequently. Conclusions: Poorly differentiated NSCLC with small intestine metastases, while rare, substantially impacts the prognosis and poses major challenges for diagnosis and treatment. Through comparisons of genetic profiles between patients and in the same patient before and after metastasis, we identified the mutations in genes such as TP53, LRP1B, and FGFR2, which were correlated with the occurrence and progression of poorly differentiated NSCLC, as well as its small intestinal metastasis. This discovery has the potential to guide clinicians in developing personalized treatment plans through the manipulation of targeted and radiation therapies.

MLL1 inhibits the neurogenic potential of SCAPs by interacting with WDR5 and repressing HES1.

Mesenchymal stem cell (MSC)-based therapy has emerged as a promising treatment for spinal cord injury (SCI), but improving the neurogenic potential of MSCs remains a challenge. Mixed lineage leukemia 1 (MLL1), an H3K4me3 methyltransferases, plays a critical role in regulating lineage-specific gene expression and influences neurogenesis. In this study, we investigated the role and mechanism of MLL1 in the neurogenesis of stem cells from apical papilla (SCAPs). We examined the expression of neural markers, and the nerve repair and regeneration ability of SCAPs using dynamic changes in neuron-like cells, immunofluorescence staining, and a SCI model. We employed a coimmunoprecipitation (Co-IP) assay, real-time RT-PCR, microarray analysis, and chromatin immunoprecipitation (ChIP) assay to investigate the molecular mechanism. The results showed that MLL1 knock-down increased the expression of neural markers, including neurogenic differentiation factor (NeuroD), neural cell adhesion molecule (NCAM), tyrosine hydroxylase (TH), ßIII-tubulin and Nestin, and promoted neuron-like cell formation in SCAPs. In vivo, a transplantation experiment showed that depletion of MLL 1 in SCAPs can restore motor function in a rat SCI model. MLL1 can combine with WD repeat domain 5 (WDR5) and WDR5 inhibit the expression of neural markers in SCAPs. MLL1 regulates Hairy and enhancer of split 1 (HES1) expression by directly binds to HES1 promoters via regulating H3K4me3 methylation by interacting with WDR5. Additionally, HES1 enhances the expression of neural markers in SCAPs. Our findings demonstrate that MLL1 inhibits the neurogenic potential of SCAPs by interacting with WDR5 and repressing HES1. These results provide a potential therapeutic target for promoting the recovery of motor function in SCI patients.

tRNA-derived small RNA changes in bone marrow stem cells under hypoxia and osteogenic conduction.

BACKGROUND: Tissue engineering using bone mesenchymal stem cells (BMSCs) transplantation is a promising therapeutic for bone regeneration. However, the effect of bone regeneration remains unsatisfactory due to the BMSCs' functional abnormality influenced by hypoxia. In this study, we attempt to explore the mechanism of osteogenic differentiation of BMSCs under hypoxic conditions from the perspective of non-coding RNA regulation. METHODS: The study employed BMSCs obtained from healthy donors and simulated hypoxia using CoCl2 stimulation. High-throughput sequencing technique was used to identify differential expression profiles of tRNA-derived small RNA (tsRNA) in three experimental groups: BMSCs-0d, BMSCs-7d and BMSCs-0d-CoCl2 . TargetScan and miRanda algorithms were used to determine tsRNA target genes, while Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis were employed for the prediction of biological functions. Real-time reverse transcriptase-polymerase chain reaction (Real-time RT-PCR) was carried out on four selected differentially expressed tsRNAs. RESULTS: After the osteogenic induction and CoCl2 stimulated separately, there were 19 tsRNAs differentially expressed in BMSCs, including 14 upregulated and five downregulated. According to the analysis of biological information, these tsRNAs may regulate 311 potential target genes and mainly enrich the pathways such as metabolic pathways, Wnt signalling pathway, osteoclast differentiation, cellular senescence and mTOR signalling pathway. The results of Real-time RT-PCR for 3'tiRNA-41-GlnTTG-6, 3'tiRNA-42-LysTTT-8, 5'tiRNA-35-CysACA-1 and tRF3a-AsnGTT-9 were consistent with small RNA sequencing data. CONCLUSION: We discovered the tsRNA that changes the process of osteogenesis and hypoxia, which provides new targets for promoting survival and regeneration functions after BMSCs transplantation.

KDM6B Negatively Regulates the Neurogenesis Potential of Apical Papilla Stem Cells via HES1.

Stem cells from the apical papilla (SCAPs) are used to regulate the microenvironment of nerve defects. KDM6B, which functions as an H3K27me3 demethylase, is known to play a crucial role in neurogenesis. However, the mechanism by which KDM6B influences the neurogenesis potential of SCAPs remains unclear. We evaluated the expression of neural markers in SCAPs by using real-time RT-PCR and immunofluorescence staining. To assess the effectiveness of SCAP transplantation in the SCI model, we used the BBB scale to evaluate motor function. Additionally, toluidine blue staining and Immunofluorescence staining of NCAM, NEFM, ß-III-tubulin, and Nestin were used to assess nerve tissue remodeling. Further analysis was conducted through Microarray analysis and ChIP assay to study the molecular mechanisms. Our results show that KDM6B inhibits the expression of NeuroD, TH, ß-III tubulin, and Nestin. In vivo studies indicate that the SCAP-KDM6Bsh group is highly effective in restoring spinal cord structure and motor function in rats suffering from SCI. Our findings suggest that KDM6B directly binds to the HES1 promoter via regulating H3K27me3 and HES1 expression. In conclusion, our study can help understand the regulatory role of KDM6B in neurogenesis and provide more effective treatments for nerve injury.

METTL3 Promotes Osteo/Odontogenic Differentiation of Stem Cells by Inhibiting miR-196b-5p Maturation.

Mesenchymal stem cells (MSCs) have been considered a potential method for the regeneration of tooth and maxillofacial bone defects based on the multidirectional differentiation characteristics of MSCs. miRNAs have been found to play a key role in the differentiation of MSCs. However, its effectiveness still needs to be improved, and its internal mechanism is still unclear. In the present study, our data discovered that the knockdown of miR-196b-5p promoted alkaline phosphatase (ALP) activity assay, mineralization in vitro, and expressions of osteo/odontogenic differentiation markers DSPP and OCN and enhanced in vivo osteo/odontogenic differentiation of stem cells of the apical papilla (SCAPs). Mechanistically, the results indicated that METTL3-dependent N6-methyladenosine (m6A) methylation inhibited miR-196b-5p maturation by the microprocessor protein DGCR8. Moreover, miR-196b-5p indirectly negatively regulates METTL3 in SCAPs. Then, METTL3 was found to strengthen the ALP activity assay, mineralization, and expressions of osteo/dentinogenic differentiation markers. Taken together, our findings highlight the critical roles of the METTL3-miR-196b-5p signaling axis in an m6A-dependent manner in osteo/odontogenic differentiation of SCAPs, identifying some potential targets for tooth and maxillofacial bone defects.

GradMDM: Adversarial Attack on Dynamic Networks.

Dynamic neural networks can greatly reduce computation redundancy without compromising accuracy by adapting their structures based on the input. In this paper, we explore the robustness of dynamic neural networks against energy-oriented attacks targeted at reducing their efficiency. Specifically, we attack dynamic models with our novel algorithm GradMDM. GradMDM is a technique that adjusts the direction and the magnitude of the gradients to effectively find a small perturbation for each input, that will activate more computational units of dynamic models during inference. We evaluate GradMDM on multiple datasets and dynamic models, where it outperforms previous energy-oriented attack techniques, significantly increasing computation complexity while reducing the perceptibility of the perturbations https://github.com/lingengfoo/GradMDM.