Tooth pulpitis is a prevalent oral disorder. Understanding the underlying mechanisms of pulpitis and developing effective treatment strategies hold great significance. Ferroptosis has recently emerged as a new form of cell death, but the role of ferroptosis in pulpitis remains largely unknown. In our study, single-cell RNA sequencing (scRNA-seq) was used to identify cellular heterogeneity between 3 pulpitis tissue and 3 healthy pulp tissue, and explored ferroptosis occurrence in pulpitis tissue and inflamed dental pulp cells (DPCs). In scRNA-seq, 40 231 cells (Pulpitis: 17 814; Healthy pulp: 22 417) were captured, and visualized into 12 distinct cell clusters. Differentially expressed ferroptosis-related genes (DE-FRGs) were almost presented in each cluster in pulpitis vs healthy pulp. ROS and Fe²⁺ levels significantly rose, and immunohistochemistry showed low expression of GPX4 and high expression of PTGS2 in pulpitis. In LPS-stimulated DPCs, thymosin α1 increased the expression of GPX4 and FTL, and decreased expression of TNF-α, IL-1β, IL-6, and Fe²⁺ levels. In rat pulpitis models, both prothymosin α (PTMA, precursor of thymosin α1) gelatin sponge placed at the hole of pulp (LPS-P(gs)) and PTMA injection in pulp (LPS-P(i)) significantly reduced infiltration of inflammatory cells and expression of PTGS2, and increased the expression of GPX4. In RNA sequencing, the expression of DE-FRGs were reversed when thymosin α1 were added in LPS-stimulated DPCs. Collectively, single-cell atlas reveals cellular heterogeneity between pulpitis and healthy pulp, and ferroptosis occurrence in pulpitis. Thymosin α1 may reduce ferroptosis in DPCs to alleviate pulpitis and thus potentially has the ability to treat pulpitis.
Ferroptosis/drug effects* ; Dental Pulp/drug effects* ; Animals ; Pulpitis/pathology* ; Rats ; Thymalfasin/pharmacology* ; Humans ; Male ; Thymosin/pharmacology* ; Disease Models, Animal ; Rats, Sprague-Dawley

This study aimed to investigate the regulatory effect and mechanism of thymopentin on the growth of subcutaneous hepatocellular carcinoma in mice. A subcutaneous tumor model of Hepa1-6 liver cancer in immunocompetent mice was constructed, with three randomly divided groups based on tumor volume: control group, low-dose thymopentin (TP5) group (10 mg/kg), and high-dose TP5 group (20 mg/kg), with 6 mice in each group. Drugs were administered, and the intervention effect of thymopentin on tumor growth was evaluated. Hepa1-6 cells were then cultured in vitro and treated with blank medium and TP5 of different concentrations (10, 100, 1000 ng/mL) for 72 hours. Cell viability was detected by sulforhodamine B (SRB) colorimetry. A subcutaneous tumor model of liver cancer LM3 in immunocompromised mice was constructed, with three randomly divided groups based on tumor volume: control group, TP5 group (20 mg/kg), and positive drug Sorafinib group (30 mg/kg). The intervention effect of thymopentin on the growth of subcutaneous tumors in immunocompromised mice was evaluated. Flow cytometry was used to analyze the changes in the proportion of T cells and myeloid-derived suppressor cells (MDSCs) in the tumor microenvironment 11 days after TP5 administration in the Hepa1-6 model. MDSCs were cultured in vitro and treated with TP5. The effect of TP5 on MDSCs was evaluated by detecting the levels of ROS, IL-6, and NO, which are effector molecules of MDSCs. The mouse subcutaneous liver cancer model was established again using C57BL/6N mice. After 10 days, they were randomly divided into four groups based on tumor volume: control group, low-dose TP5 group (10 mg/kg), high-dose TP5 group (20 mg/kg), and arginine-deficient TP5 group (15 mg/kg). Drugs were administered continuously for 11 days, and the intervention effect of arginine-deficient TP5 on tumor growth was evaluated based on tumor weight. Annexin-V staining was used to detect the impact of TP5 on T cell survival. The results showed that both low and high doses of TP5 inhibited the growth of subcutaneous liver cancer in immunocompetent mice (P < 0.05), yet TP5 had no direct inhibitory effect on the proliferation of tumor cells cultured in vitro. Besides, a high dose of TP5 could not inhibit the growth of subcutaneous liver cancer in immunocompromised mice. Furthermore, TP5 promoted the infiltration of CD4 and CD8 T cells but decreased MDSCs in the subcutaneous tumor microenvironment of immunocompetent mice. TP5 did not affect the levels of ROS, IL-6, and NO in MDSCs. Lastly, arginine-deficient TP5 could not inhibit the growth of subcutaneous liver cancer in immunocompetent mice. Accordingly, TP5 but not arginine-deficient TP5 promoted the increase in the proportion of viable CD4 and CD8 T cells cultured in vitro. These results suggest that TP5 may inhibit the growth of liver cancer by increasing T cell number in the liver cancer microenvironment.
thymopentin ; hepatocellular carcinoma ; tumor microenvironment ; arginine ; T cells

OBJECTIVE: To investigate the role and mechanism of thymosin beta 4 (Tβ4) in oxidative stress injury of spinal cord-derived neural stem/progenitor cells (NSPCs) induced by hydrogen peroxide (H₂O₂). METHODS: NSPCs were isolated from Sprague-Dawley (SD) adult male rats, and divided into control group (untreated NSPCs cells), H₂O₂ group (NSPCs cells damaged by 500 μM H₂O₂), Tβ4 -3 groups (NSPCs were treated with 1, 2.5, 5 μg/ml Tβ4 on the basis of H₂O₂ treatment) and TAK-242 group [NSPCs were treated with 5 μg/ml Tβ4 and Toll-like receptor 4(TLR4) inhibitor TAK-242 on the basis of H₂O₂ treatment]. NSPCs were transfected with lentivirus vector of myeloid differentiation factor 88(MyD88) to construct MyD88-overexpressing cell lines, which were treated with H₂O₂ and Tβ4. The expression of Tβ4, TLR4, MyD88 were detected by qRT-PCR and Western blot. Cell viability was detected by MTT assay and lactate dehydrogenase(LDH) assay kit. Ca2+ concentration was detected by Fluo-3/AM probe method. The apoptosis of NSPCs was detected by flow cytometry and Caspase-3 and Caspase-9 kits;reactive oxygen species (ROS), superoxi dedismu-tase dismutase(SOD) activity and glutathione (GSH) content were detected by corresponding kits. Interleukin(IL)-6 and IL-1β were detected by enzyme-linked immunosorbent assay. RESULTS: The expression of Tβ4 was decreased in H₂O₂ injured NSPCs(P<0.05). Compared with H₂O₂ group, the cell viability and Ca2+ concentration was significantly increased, release of LDH and apoptosis were significantly decreased, production of ROS and pro-inflammatory cytokines were significantly decreased, and the expression levels of TLR4 and MyD88 protein were significantly decreased in Tβ4-3 groups and TAK-242 group (P<0.05). After overexpression of MyD88, cell viability, SOD activity and GSH content of NSPCs decreased, LDH release and apoptosis increased significantly (P<0.05), while after treatment with Tβ4, cell viability, SOD activity and GSH content increased, LDH release and apoptosis decreased (P<0.05). CONCLUSION Tβ4 attenuates H₂O₂-induced NSPCs oxidative stress, apoptosis and inflammation in NSPCs via inhibiting TLR4 and MyD88 pathways.
Animals ; Apoptosis ; Calcium/pharmacology* ; Cell Survival ; Hydrogen Peroxide/pharmacology* ; Male ; Myeloid Differentiation Factor 88/pharmacology* ; Oxidative Stress ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species/pharmacology* ; Spinal Cord Injuries/drug therapy* ; Stem Cells ; Superoxide Dismutase/pharmacology* ; Thymosin/metabolism* ; Toll-Like Receptor 4/metabolism*

With the aging of population and the development of social economy, the incidence of chronic wounds is increasing day by day, while the incidence of burns and trauma remains at a high level, making wound repair an increasingly concerned area in clinical practice. Thymosin β4 is a naturally occurring small molecule protein in vivo, which is widely distributed in a variety of body fluids and cells, especially in platelets. Thymosin β4 has biological activities of promoting angiogenesis, anti-inflammation, anti-apoptosis, and anti-fibrosis, and has many important functions in wound repair. Thymosin β4 has been observed to promote the healing of various wounds, such as burns, diabetic ulcers, pressure ulcers. This paper will review the molecular structure, mechanism of wound healing promotion, pharmacokinetics, and clinical application of thymosin β4, aiming to introduce its potential in wound treatment and the shortcomings of current researches.
Burns/drug therapy* ; Humans ; Pressure Ulcer ; Thymosin/therapeutic use* ; Wound Healing/physiology*

BACKGROUND: Thymosin β₄ is a multi-functional hormone-like polypeptide, being involved in cell migration, angiogenesis, and tumor metastasis. This study was undertaken to clarify the clinicopathologic implications of thymosin β₄ expression in human colorectal cancers (CRCs). METHODS: We investigated tissue sections from 143 patients with CRC by immunohistochemistry. In addition, we evaluated the expression patterns and the clinico-pathological significance of thymosin β₄ expression in association with hypoxia inducible factor-1α (HIF-1α) expression in the CRC series. RESULTS: High expression of thymosin β₄ was significantly correlated with lymphovascular invasion, invasion depth, regional lymph node metastasis, distant metastasis, and TNM stage. Patients with high expression of thymosin β₄ showed poor recurrence-free survival (p = .001) and poor overall survival (p = .005) on multivariate analysis. We also found that thymosin β4 and HIF-1α were overexpressed and that thymosin β₄ expression increased in parallel with HIF-1α expression in CRC. CONCLUSIONS: A high expression level of thymosin β₄ indicates poor clinical outcomes and may be a useful prognostic factor in CRC. Thymosin β₄ is functionally related with HIF-1α and may be a potentially valuable biomarker and possible therapeutic target for CRC.
Anoxia* ; Cell Movement ; Colorectal Neoplasms* ; Humans* ; Immunohistochemistry ; Lymph Nodes ; Multivariate Analysis ; Neoplasm Metastasis ; Thymosin*

Dysfunction or loss of blood vessel causes several ischemic diseases. Although endothelial progenitor cells (EPCs) are a promising source for cell-based therapy, ischemia-induced pathophysiological condition limits the recovery rate by causing drastic cell death. To overcome this issue, we attempted to develop a cell-targeted peptide delivery and priming system to enhance EPCbased neovascularization using an engineered M13 bacteriophage harboring nanofibrous tubes displaying ∼ 2700 multiple functional motifs. The M13 nanofiber was modified by displaying RGD, which is an integrin-docking peptide, on the minor coat protein, and bymutilayering SDKPmotifs,which are the key active sites for thymosin b4, on themajor coat protein. The engineered M13 nanofiber dramatically enhanced ischemic neovascularization by activating intracellular and extracellular processes such as proliferation, migration, and tube formation in the EPCs. Furthermore, transplantation of the primed EPCs with the M13 nanofiber harboring RGD and SDKP facilitated functional recovery and neovascularization in a murine hindlimb ischemia model. Overall, this study demonstrates the effectiveness of theM13 nanofiber-based novel peptide deliveryandprimingstrategy inpromotingEPC bioactivity and neovessel regeneration. To our knowledge, this is first report onM13 nanofibers harboring dual functional motifs, the use of which might be a novel strategy for stem and progenitor cell therapy against cardiovascular ischemic diseases.
Animals ; Bacteriophages ; Blood Vessels ; Catalytic Domain ; Cell Death ; Endothelial Progenitor Cells* ; Hindlimb ; Ischemia ; Nanofibers* ; Regeneration ; Stem Cells ; Thymosin

Thymic hyperplasia is frequently observed in Graves' disease. However, detectable massive enlargement of the thymus is rare, and the mechanism of its formation has remained elusive. This case showed dynamic changes in thymic hyperplasia on serial computed tomography images consistent with changes in serum thyrotropin receptor (TSH-R) antibodies and thyroid hormone levels. Furthermore, the patient's thymic tissues underwent immunohistochemical staining for TSH-R, which demonstrated the presence of thymic TSH-R. The correlation between serum TSH-R antibody levels and thymic hyperplasia sizes and the presence of TSH-R in her thymus suggest that TSH-R antibodies could have a pathogenic role in thymic hyperplasia.
Adult ; Female ; Graves Disease/*complications/surgery/therapy ; Humans ; Male ; Receptors, Thyrotropin/blood ; Thymus Gland/diagnostic imaging ; Thymus Hyperplasia/*diagnostic imaging/etiology/immunology ; Thyroid Hormones ; Thyroidectomy ; Thyrotropin/blood ; Tomography, X-Ray Computed ; Young Adult

Thymosin β4 (Tβ4) is a key factor in cardiac development, growth, disease, epicardial integrity, blood vessel formation and has cardio-protective properties. However, its role in murine embryonic stem cells (mESCs) proliferation and cardiovascular differentiation remains unclear. Thus we aimed to elucidate the influence of Tβ4 on mESCs. Target genes during mESCs proliferation and differentiation were detected by real-time PCR or Western blotting, and patch clamp was applied to characterize the mESCs-derived cardiomyocytes. It was found that Tβ4 decreased mESCs proliferation in a partial dose-dependent manner and the expression of cell cycle regulatory genes c-myc, c-fos and c-jun. However, mESCs self-renewal markers Oct4 and Nanog were elevated, indicating the maintenance of self-renewal ability in these mESCs. Phosphorylation of STAT3 and Akt was inhibited by Tβ4 while the expression of RAS and phosphorylation of ERK were enhanced. No significant difference was found in BMP2/BMP4 or their downstream protein smad. Wnt3 and Wnt11 were remarkably decreased by Tβ4 with upregulation of Tcf3 and constant β-catenin. Under mESCs differentiation, Tβ4 treatment did not change the expression of cardiovascular cell markers α-MHC, PECAM, and α-SMA. Neither the electrophysiological properties of mESCs-derived cardiomyocytes nor the hormonal regulation by Iso/Cch was affected by Tβ4. In conclusion, Tβ4 suppressed mESCs proliferation by affecting the activity of STAT3, Akt, ERK and Wnt pathways. However, Tβ4 did not influence the in vitro cardiovascular differentiation.
Animals ; Cell Cycle ; drug effects ; genetics ; Cell Differentiation ; drug effects ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Dose-Response Relationship, Drug ; Extracellular Signal-Regulated MAP Kinases ; genetics ; metabolism ; Gene Expression Regulation ; drug effects ; JNK Mitogen-Activated Protein Kinases ; genetics ; metabolism ; Mice ; Mouse Embryonic Stem Cells ; cytology ; drug effects ; metabolism ; Myocytes, Cardiac ; cytology ; drug effects ; metabolism ; Nanog Homeobox Protein ; genetics ; metabolism ; Octamer Transcription Factor-3 ; genetics ; metabolism ; Patch-Clamp Techniques ; Primary Cell Culture ; Proto-Oncogene Proteins c-akt ; genetics ; metabolism ; Proto-Oncogene Proteins c-fos ; genetics ; metabolism ; Proto-Oncogene Proteins c-myc ; genetics ; metabolism ; STAT3 Transcription Factor ; genetics ; metabolism ; Signal Transduction ; Thymosin ; pharmacology

The thymus is a vital primary lymphoid organ that provides unique microenvironments for the proliferation, differentiation, and maturation of T cells. With advancing age, however, the thymus gradually undergoes age-related involution and reduction in immune function, which are characterized by decreases in tissue size, cellularity, and naïve T cell output. This dynamic process leads to the reduced efficacy of the immune system with age and contributes to the increased susceptibility to infection, autoimmune disease, and cancer. In addition, bone marrow transplantation, radio-chemotherapy and virus infection also impair the thymus and give rise to the decline in immune function. Therefore, understanding the molecular mechanisms involved in age-related thymic involution and development of novel therapeutic strategies for thymic rejuvenation have gained considerable interests in recent years. This review emphasizes thymic microenvironments and thymocyte-stromal cell interactions and summarizes our current knowledge about thymic rejuvenation in terms of sex steroid, cytokines, growth factors, hormones, transcription factors, cell graft, and microRNAs. At the end of each discussion, we also highlight unanswered issues and describe possible future research directions.
Aging ; Cell Differentiation ; Cytokines ; Gonadal Steroid Hormones ; Hormones ; Humans ; Intercellular Signaling Peptides and Proteins ; Rejuvenation ; Stromal Cells ; T-Lymphocytes ; Thymus Gland

BACKGROUNDThymosin beta-4 (TB-4) is considered key roles in tissue development, maintenance and pathological processes. The study aimed to prove TB-4 positive biological function on nucleus pulposus (NP) cell apoptosis and slowing the process of cell aging while increasing the cell proliferation.

METHODSTB-4 recombinant adeno-associated virus (AAV) was constructed and induced to human NP cells. Cell of same group were cultured without gene modification as controlled group. Proliferation capacity and cell apoptosis were observed during 6 passages of the cells. Morphology and expression of the TB-4 gene were documented as parameter of cell activity during cell passage.

RESULTSNP cells with TB-4 transfection has normal TB-4 expression and exocytosis. NP cells with TB-4 transfection performed significantly higher cell activity than that at the control group in each generation. TB-4 recombinant AAV-transfected human NP cells also show slower cell aging, lower cell apoptosis and higher cell proliferation than control group.

CONCLUSIONSTB-4 can prevent NP cell apoptosis, slow NP cell aging and promote NP cell proliferation. AAV transfection technique was able to highly and stably express TB-4 in human NP cells, which may provide a new pathway for innovation in the treatment of intervertebral disc degenerative diseases.

Apoptosis ; genetics ; physiology ; Cell Line ; Cell Proliferation ; genetics ; physiology ; Cells, Cultured ; Cellular Senescence ; genetics ; physiology ; Dependovirus ; genetics ; Humans ; Immunohistochemistry ; Intervertebral Disc ; metabolism ; pathology ; Male ; Thymosin ; genetics ; metabolism