Neuronal reprogramming is an innovative technique for converting non-neuronal somatic cells into neurons that can be used to replace lost or damaged neurons, providing a potential effective therapeutic strategy for central nervous system (CNS) injuries or diseases. Transcription factors have been used to induce neuronal reprogramming, while their reprogramming efficiency is relatively low, and the introduction of exogenous genes may result in host gene instability or induce gene mutation. Therefore, their future clinical application may be hindered by these safety concerns. Compared with transcription factors, small-molecule compounds have unique advantages in the field of neuronal reprogramming, which can overcome many limitations of traditional transcription factor-induced neuronal reprogramming. Here, we review the recent progress in the research of small-molecule compound-mediated neuronal reprogramming and its application in CNS regeneration and repair.
Humans ; Cellular Reprogramming/drug effects* ; Neurons/cytology* ; Animals ; Transcription Factors ; Small Molecule Libraries/pharmacology* ; Nerve Regeneration

OBJECTIVE: To summarize the latest research progress of graphene and its derivatives (GDs) in bone repair. METHODS: The relevant research literature at home and abroad in recent years was extensively accessed. The properties of GDs in bone repair materials, including mechanical properties, electrical conductivity, and antibacterial properties, were systematically summarized, and the unique advantages of GDs in material preparation, functionalization, and application, as well as the contributions and challenges to bone tissue engineering, were discussed. RESULTS: The application of GDs in bone repair materials has broad prospects, and the functionalization and modification technology effectively improve the osteogenic activity and material properties of GDs. GDs can induce osteogenic differentiation of stem cells through specific signaling pathways and promote osteogenic activity through immunomodulatory mechanisms. In addition, the parameters of GDs have significant effects on the cytotoxicity and degradation behavior. CONCLUSION GDs has great potential in the field of bone repair because of its excellent physical and chemical properties and biological properties. However, the cytotoxicity, biodegradability, and functionalization strategies of GDs still need to be further studied in order to achieve a wider application in the field of bone tissue engineering.
Graphite/pharmacology* ; Tissue Engineering/methods* ; Humans ; Osteogenesis/drug effects* ; Biocompatible Materials/pharmacology* ; Bone Regeneration ; Tissue Scaffolds/chemistry* ; Cell Differentiation ; Bone and Bones ; Bone Substitutes/chemistry* ; Animals

OBJECTIVE: To review the research progress of strontium (Sr) modified β-tricalcium phosphate composite biomaterials (SrTCP) promoting osteogenesis through immune regulation, and provides reference and theoretical support for the further development and research of SrTCP bone repair materials in bone tissue engineering in the future. METHODS: The literature about SrTCP promoting osteogenesis through immune regulation at home and abroad in recent years was extensively reviewed, and the preparation methods, immune mechanism and application of promoting osteogenesis were summarized and analyzed. RESULTS: The preparation methods of SrTCP include solid-state reaction sintering method, solution combustion quenching method, direct doping method, ion substitution method, etc. SrTCP has immune regulatory effects, which can play an immune regulatory role in inducing macrophage polarization, inducing angiogenesis and anti oxidative stress to promote osteogenesis. CONCLUSION At present, studies have shown that SrTCP can promote bone defect repair through immune regulation. Subsequent studies can start from the control of the optimal repair concentration and release rate of Sr, and further clarify the specific mechanism of SrTCP in promoting angiogenesis and anti oxidative stress, which is helpful to develop new materials for bone defect repair.
Calcium Phosphates/pharmacology* ; Strontium/pharmacology* ; Biocompatible Materials/pharmacology* ; Humans ; Osteogenesis/drug effects* ; Tissue Engineering/methods* ; Bone Substitutes/pharmacology* ; Bone Regeneration/drug effects* ; Animals ; Tissue Scaffolds/chemistry* ; Neovascularization, Physiologic/drug effects* ; Macrophages/immunology*

OBJECTIVE: To investigate the effects of removing microglia from spinal cord on nerve repair and functional recovery after spinal cord injury (SCI) in mice. METHODS: Thirty-nine 6-week-old female C57BL/6 mice were randomly divided into control group ( n=12), SCI group ( n=12), and PLX3397+SCI group ( n=15). The PLX3397+SCI group received continuous feeding of PLX3397, a colony-stimulating factor 1 receptor inhibitor, while the other two groups were fed a standard diet. After 14 days, both the SCI group and the PLX3397+SCI group were tested for ionized calcium binding adapter molecule 1 (Iba1) to confirm that the PLX3397+SCI group had completely depleted the spinal cord microglia. The SCI model was then prepared by clamping the spinal cord in both the SCI group and the PLX3397+SCI group, while the control group underwent laminectomy. Preoperatively and at 1, 3, 7, 14, 21, and 28 days postoperatively, the Basso Mouse Scale (BMS) was used to assess the hind limb function of mice in each group. At 28 days, a footprint test was conducted to observe the gait of the mice. After SCI, spinal cord tissue from the injury site was taken, and Iba1 immunofluorescence staining was performed at 7 days to observe the aggregation and proliferation of microglia in the spinal cord. HE staining was used to observe the formation of glial scars at the injury site at 28 days; glial fibrillary acidic protein (GFAP) immunofluorescence staining was applied to astrocytes to assess the extent of the injured area; neuronal nuclei antigen (NeuN) immunofluorescence staining was used to evaluate neuronal survival. And 5-hydroxytryptamine (5-HT) immunofluorescence staining was performed to assess axonal survival at 60 days. RESULTS: All mice survived until the end of the experiment. Immunofluorescence staining revealed that the microglia in the spinal cord of the PLX3397+SCI group decreased by more than 95% compared to the control group after 14 days of continuous feeding with PLX3397 ( P<0.05). Compared to the control group, the BMS scores in the PLX3397+SCI group and the SCI group significantly decreased at different time points after SCI ( P<0.05). Moreover, the PLX3397+SCI group showed a further decrease in BMS scores compared to the SCI group, and exhibited a dragging gait. The differences between the two groups were significant at 14, 21, and 28 days ( P<0.05). HE staining at 28 days revealed that the SCI group had formed a well-defined and dense gliotic scar, while the PLX3397+SCI group also developed a gliotic scar, but with a more blurred and loose boundary. Immunofluorescence staining revealed that the number of microglia near the injury center at 7 days increased in the SCI group than in the control group, but the difference between groups was not significant ( P>0.05). In contrast, the PLX3397+SCI group showed a significant reduction in microglia compared to both the control and SCI groups ( P<0.05). At 28 days after SCI, the area of spinal cord injury in the PLX3397+SCI group was significantly larger than that in SCI group ( P<0.05); the surviving neurons significantly reduced compared with the control group and SCI group ( P<0.05). The axonal necrosis and retraction at 60 days after SCI were more obvious. CONCLUSION The removal of microglia in the spinal cord aggravate the tissue damage after SCI and affecte the recovery of motor function in mice, suggesting that microglia played a neuroprotective role in SCI.
Animals ; Spinal Cord Injuries/surgery* ; Microglia/pathology* ; Female ; Mice ; Mice, Inbred C57BL ; Nerve Regeneration/drug effects* ; Spinal Cord/pathology* ; Pyrroles/administration & dosage* ; Aminopyridines/administration & dosage* ; Recovery of Function ; Disease Models, Animal ; Calcium-Binding Proteins/metabolism* ; Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/antagonists & inhibitors* ; Microfilament Proteins/metabolism* ; Glial Fibrillary Acidic Protein/metabolism*

Prostate cancer is the second most common malignancy and the sixth leading cause of cancer-related death in men worldwide. Radical prostatectomy (RP) is the standard treatment for localized prostate cancer, but the procedure often results in postoperative erectile dysfunction (ED). The poor efficacy of phosphodiesterase 5 inhibitors after surgery highlights the need to develop new therapies to enhance cavernous nerve regeneration and improve the erectile function of these patients. In the present study, we aimed to examine the potential of heparin-binding epidermal growth factor-like growth factor (HB-EGF) in preserving erectile function in cavernous nerve injury (CNI) mice. We found that HB-EGF expression was reduced significantly on the 1 st day after CNI in penile tissue. Ex vivo and in vitro studies showed that HB-EGF promotes major pelvic ganglion neurite sprouting and neuro-2a (N2a) cell migration. In vivo studies showed that exogenous HB-EGF treatment significantly restored the erectile function of CNI mice to 86.9% of sham levels. Immunofluorescence staining showed that mural and neuronal cells were preserved by inducing cell proliferation and reducing apoptosis and reactive oxygen species production. Western blot analysis showed that HB-EGF upregulated protein kinase B and extracellular signal-regulated kinase activation and neurotrophic factor expression. Overall, HB-EGF is a major promising therapeutic agent for treating ED in postoperative RP.
Animals ; Male ; Heparin-binding EGF-like Growth Factor/therapeutic use* ; Erectile Dysfunction/etiology* ; Mice ; Penis/drug effects* ; Nerve Regeneration/drug effects* ; Penile Erection/drug effects* ; Peripheral Nerve Injuries/drug therapy* ; Cell Proliferation/drug effects* ; Apoptosis/drug effects* ; Cell Movement/drug effects* ; Prostatectomy/adverse effects* ; Mice, Inbred C57BL ; Reactive Oxygen Species/metabolism*

OBJECTIVES: To investigate the effect of a variety of kidney-tonifying Chinese medicines on thymus regeneration after acute degeneration in mice. METHODS: Forty-eight 8-week-old male BALB/c mice were randomly divided into normal control group, model control group, negative control group, positive control group, the fructus of Cnidium monnieri (L.) Cuss. group, the fructus of Psoralea corylifolia (L.) group, the fructus of Rubus chingii Hu group, and the tuber onion seed group, with 6 mice in each group. Except for the normal control group, mice in the other groups received intraperitoneal injections of rapamycin (1 mg·kg^－1·d^－1) for 5 consecutive days followed by 14 h of starvation to induce acute thymus degeneration. After successful modeling, in treatment groups ethanol extract of the fructus of Cnidium monnieri (L.) Cuss. (0.78 g·kg^－1·d^－1), fructus of Psoralea corylifolia (L.) (0.39 g·kg^－1·d^－1), fructus of Rubus chingii Hu (0.78 g·kg^－1·d^－1) or the tuber onion seed(0.39 g·kg^－1·d^－1) was intraperitoneally injected once a day for 5 days; while the negative control group was given equal volume of normal saline, and the positive control group was given metformin (300 mg·kg^－1·d^－1). The grip strength was measured with a grip tester 2 h after the last administration. The pathological changes of thymus were observed by hematoxylin and eosin (HE) staining. The structure and distribution of thymic epithelial cells were observed by multiple immunofluorescence method. The proportion of T cell subsets in thymus and peripheral blood was analyzed by flow cytometry. The level of T cell receptor excision circles (TREC) in the genomic DNA of mouse spleen mononuclear cells was detected by quantitative polymerase chain reaction (PCR) for evaluation of thymic output function. The expression of thymus aging- and function-related factors in the thymus tissue were detected by quantitative reverse transcription PCR. The expression of cyclin-dependent kinase inhibitor 1A (p21) and tumor protein 53 (p53) were verified by immunohistochemistry. RESULTS: Rapamycin induced thymic atrophy and significantly reduced limb grip strength in mice (P<0.01). Compared with the negative control group, the limb grip strength of mice in the fructus of Psoralea corylifolia (L.) group, the fructus of Rubus chingii Hu group and the tuber onion seed group was significantly enhanced (all P<0.05), and the level of TREC in spleen of the mice in each administration group was reduced (all P<0.05). Among Chinese herb medicine-treatment groups, the recovery of thymus function and tissue structure in the tuber onion seed group was most obvious. Further study showed that compared with the negative control group, the proportion of CD4 single positive cells (CD3⁺TCR-β⁺CD4⁺CD8^－) in the thymus of the tuber onion seed group was significantly increased (P<0.01), and the proportion of CD3⁺CD28⁺ T cell and CD3⁺CD8⁺CD28⁺ T cell in peripheral blood was significantly increased (all P<0.01). The mRNA levels of IL-1α, IL-6, p21 and p53 in thymocytes were decreased (all P<0.05). The results of immunohistochemistry further confirmed the decrease in p21 and p53 expression. In normal mice, tuber onion seed was observed to enhance limb grip strength (P<0.01), while suppressing thymus output and change the distribution of T cell subsets, and there was no significant effect on thymus weight and the expression of Foxn1, SIRT1, p21, CXCL2 and PTMα. CONCLUSIONS The tuber onion seed and other kidney-tonifying traditional Chinese medicines can accelerate the regeneration process of mouse thymus after acute degeneration induced by rapamycin in mice, and the tuber onion seed exhibits the most pronounced therapeutic effect.
Animals ; Mice ; Male ; Mice, Inbred BALB C ; Thymus Gland/physiology* ; Drugs, Chinese Herbal/pharmacology* ; Sirolimus/adverse effects* ; Regeneration/drug effects*

Peripheral nerve injury (PNI) encompasses damage to nerves located outside the central nervous system, adversely affecting both motor and sensory functions. Although peripheral nerves possess an intrinsic capacity for self-repair, severe injuries frequently result in significant tissue loss and erroneous axonal junctions, thereby impeding complete recovery and potentially causing neuropathic pain. Various therapeutic strategies, including surgical interventions, biomaterials, and pharmacological agents, have been developed to enhance nerve repair processes. While preclinical studies in animal models have demonstrated the efficacy of certain pharmacological agents in promoting nerve regeneration and mitigating inflammation, only a limited number of these agents have been translated into clinical practice to expedite nerve regeneration. Chinese herb medicine (CHM) possesses a longstanding history in the treatment of various ailments and demonstrates potential efficacy in addressing PNI through its distinctive, cost-effective, and multifaceted methodologies. This review critically examines the advancements in the application of CHM for PNI treatment and nerve regeneration. In particular, we have summarized the most commonly employed and rigorously investigated CHM prescriptions, individual herbs, and natural products, elucidating their respective functions and underlying mechanisms in the context of PNI treatment. Furthermore, we have deliberated on the prospective development of CHM in both clinical practice and fundamental research.
Drugs, Chinese Herbal/pharmacology* ; Humans ; Peripheral Nerve Injuries/drug therapy* ; Animals ; Nerve Regeneration/drug effects* ; Medicine, Chinese Traditional

OBJECTIVES: To investigate the core targets and immunomodulatory mechanisms of Huoluo Xiaoling Pellet (HLXLP) for promoting tissue repair. METHODS: Network pharmacology and protein-protein interaction network were used to screen active components in HLXLP, the disease-related targets and the core targets, followed by GO and KEGG enrichment analyses and molecular docking to predict the pharmacological mechanisms. The toxicity of HLXLP was evaluated in zebrafish, and in a tissue regeneration model established in 3 dpf zebrafish larvae by amputating 95% of the tail fin, the effects of a formulated zebrafish embryo culture medium and 10, 20, and 40 μg/mL of aqueous extract of HLXLP on tissue regeneration was evaluated; RT-qPCR was performed to detect mRNA expressions of tissue regeneration marker genes and the core target genes. Transgenic zebrafish with fluorescently labeled macrophages and neutrophils were used to observe immune cell migration during tissue regeneration, and macrophage polarization at different stages was assessed with RT-qPCR. RESULTS: We identified a total of 149 intersected targets between HLXLP active components and tissue repair and 5 core targets (AKT1, IL-6, TNF-α, EGFR and STAT3). GO and KEGG analyses suggested that the effects of HLXLP were mediated primarily through the JAK-STAT pathway, adhesion junctions and positive regulation of cell migration. HLXLP was minimally toxic below 40 μg/mL and lethal at 320 μg/mL in zebrafish, and caused renal and pericardial edema and vascular defects above 80 μg/mL. In zebrafish with tail fin amputation, HLXLP significantly promoted tissue regeneration, reduced IL-6 and TNF-α and enhanced AKT1, EGFR and STAT3 mRNA expressions, modulated neutrophil and macrophage recruitment to the injury sites, and regulated M1/M2 macrophage polarization during tissue regeneration. CONCLUSIONS HLXLP promotes zebrafish tail fin regeneration through multiple active components, targets and pathways for immunomodulation of immune cell migration and macrophage polarization to suppress inflammation and accelerate healing.
Animals ; Zebrafish/physiology* ; Animal Fins/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Regeneration/drug effects* ; Network Pharmacology ; Signal Transduction ; Macrophages

Regenerating periodontal bone defect surrounding periodontal tissue is crucial for orthodontic or dental implant treatment. The declined osteogenic ability of periodontal ligament stem cells (PDLSCs) induced by inflammation stimulus contributes to reduced capacity to regenerate periodontal bone, which brings about a huge challenge for treating periodontitis. Here, inspired by the adhesive property of mussels, we have created adhesive and mineralized hydrogel microspheres loaded with traditional compound cordycepin (MMS-CY). MMS-CY could adhere to the surface of alveolar bone, then promote the migration capacity of PDLSCs and thus recruit them to inflammatory periodontal tissues. Furthermore, MMS-CY rescued the impaired osteogenesis and ligament-forming capacity of PDLSCs, which were suppressed by the inflammation stimulus. Moreover, MMS-CY also displayed the excellent inhibitory effect on the osteoclastic activity. Mechanistically, MMS-CY inhibited the premature senescence induced by the inflammation stimulus through the nuclear factor erythroid 2-related factor (NRF2) pathway and reducing the DNA injury. Utilizing in vivo rat periodontitis model, MMS-CY was demonstrated to enhance the periodontal bone regeneration by improving osteogenesis and inhibiting the osteoclastic activity. Altogether, our study indicated that the multi-pronged approach is promising to promote the periodontal bone regeneration in periodontitis condition by reducing the inflammation-induced stem cell senescence and maintaining bone homeostasis.
Animals ; Bone Regeneration/drug effects* ; Rats ; Periodontal Ligament/cytology* ; Microspheres ; NF-E2-Related Factor 2 ; Hydrogels ; Periodontitis/therapy* ; Osteogenesis/drug effects* ; Disease Models, Animal ; Stem Cells ; Male ; Rats, Sprague-Dawley ; Humans

Dental pulp-dentin complex defects remain a major unresolved problem in oral medicines. Clinical therapeutic methods including root canal therapy and vital pulp therapy are both considered as conservative strategies, which are incapable of repairing the pulp-dentin complex defects. Although biomaterial-based strategies show remarkable progress in antibacterial, anti-inflammatory, and pulp regeneration, the important modulatory effects of nerves within pulp cavity have been greatly overlooked, making it challenging to achieve functional pulp-dentin complex regeneration. In this study, we propose an injectable bioceramics-containing composite hydrogel in combination of Li-Ca-Si (LCS) bioceramics and gelatin methacrylate matrix with photo-crosslinking properties. Due to the sustained release of bioactive Li, Ca and Si ions from LCS, the composite hydrogels possess multiple functions of promoting the neurogenic differentiation of Schwann cells, odontogenic differentiation of dental pulp stem cells, and neurogenesis-odontogenesis couples in vitro. In addition, the in vivo results showed that LCS-containing composite hydrogel can significantly promote the pulp-dentin complex repair. More importantly, LCS bioceramics-containing composite hydrogel can induce the growth of nerve fibers, leading to the re-innervation of pulp tissues. Taken together, the study suggests that LCS bioceramics can induce the innervation of pulp-dentin complex repair, offering a referable strategy of designing multifunctional filling materials for functional periodontal tissue regeneration.
Dental Pulp/drug effects* ; Hydrogels/pharmacology* ; Animals ; Ceramics/pharmacology* ; Dentin/drug effects* ; Biocompatible Materials/pharmacology* ; Rats ; Gelatin ; Regeneration/drug effects* ; Cell Differentiation/drug effects* ; Injections ; Humans ; Odontogenesis/drug effects*