OBJECTIVE: To Investigate the effects of lithocholic acid (LCA) on the balance between osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). METHODS: Twelve 10-week-old SPF C57BL/6J female mice were randomly divided into an experimental group (undergoing bilateral ovariectomy) and a control group (only removing the same volume of adipose tissue around the ovaries), with 6 mice in each group. The body mass was measured every week after operation. After 4 weeks post-surgery, the weight of mouse uterus was measured, femur specimens of the mice were taken for micro-CT scanning and three-dimensional reconstruction to analyze changes in bone mass. Tibia specimens were taken for HE staining to calculate the number and area of bone marrow adipocytes in the marrow cavity area. ELISA was used to detect the expression of bone turnover markers in the serum. Liver samples were subjected to real-time fluorescence quantitative PCR (RT-qPCR) to detect the expression of key genes related to bile acid metabolism, including cyp7a1, cyp7b1, cyp8b1, and cyp27a1. BMSCs were isolated by centrifugation from 2 C57BL/6J female mice (10-week-old). The third-generation cells were exposed to 0, 1, 10, and 100 μmol/L LCA, following which cell viability was evaluated using the cell counting kit 8 assay. Subsequently, alkaline phosphatase (ALP) staining and oil red O staining were conducted after 7 days of osteogenic and adipogenic induction. RT-qPCR was employed to analyze the expressions of osteogenic-related genes, namely ALP, Runt-related transcription factor 2 (Runx2), and osteocalcin (OCN), as well as adipogenic-related genes including Adiponectin (Adipoq), fatty acid binding protein 4 (FABP4), and peroxisome proliferator-activated receptor γ (PPARγ). RESULTS: Compared with the control group, the body mass of the mice in the experimental group increased, the uterus atrophied, the bone mass decreased, the bone marrow fat expanded, and the bone metabolism showed a high bone turnover state. RT-qPCR showed that the expressions of cyp7a1, cyp8b1, and cyp27a1, which were related to the key enzymes of bile acid metabolism in the liver, decreased significantly ( P<0.05), while the expression of cyp7b1 had no significant difference ( P>0.05). Intervention with LCA at concentrations of 1, 10, and 100 μmol/L did not demonstrate any apparent toxic effects on BMSCs. Furthermore, LCA inhibited the expressions of osteogenic-related genes (ALP, Runx2, and OCN) in a dose-dependent manner, resulting in a reduction in ALP staining positive area. Concurrently, LCA promoted the expressions of adipogenic-related genes (Adipoq, FABP4, and PPARγ), and an increase in oil red O staining positive area. CONCLUSION After menopause, the metabolism of bile acids is altered, and secondary bile acid LCA interferes with the balance of osteogenic and adipogenic differentiation of BMSCs, thereby affecting bone remodelling.
Female ; Mice ; Animals ; Core Binding Factor Alpha 1 Subunit/pharmacology* ; PPAR gamma/metabolism* ; Steroid 12-alpha-Hydroxylase/metabolism* ; Mice, Inbred C57BL ; Cell Differentiation ; Osteogenesis ; Mesenchymal Stem Cells ; Bile Acids and Salts/pharmacology* ; Bone Marrow Cells ; Cells, Cultured ; Azo Compounds

Objective To observe the expression of adhesion molecule CD226 on the small intestinal group 3 innate lymphoid cells (ILC3) in mice. Methods The bioinformatics was used to analyze the expression of CD226 on murine ILCs. Small intestinal mucosal lamina propria lymphocytes (LPL) were isolated from wild-type C57BL/6J mice, and the expression of CD226 on ILC1 and ILC3 was detected by flow cytometry. A mouse model of dextran sulfate sodium (DSS)-induced colitis was constructed to observe the changes in the expression of CD226 on ILC3. Results Both ILC1 and ILC3 in the mice small intestine expressed CD226 molecules; the proportion of ILC3 was reduced, while the expression level of CD226 on ILC3 was increased in the colitis model. Conclusion CD226 is expressed on the small intestines of mice, and although the proportion of ILC3 decreases in the DSS-induced colitis, the expression of CD226 on ILC3 increases.
Animals ; Mice ; Colitis/chemically induced* ; Immunity, Innate ; Intestine, Small ; Lymphocytes ; Mice, Inbred C57BL

Objective To explore the phenotypic conversion of regulatory T cells (Tregs) in the lungs of mice with bronchopulmonary dysplasia (BPD)-affected mice. Methods A total of 20 newborn C57BL/6 mice were divided into air group and hyperoxia group, with 10 mice in each group. The BPD model was established by exposing the newborn mice to hyperoxia. Lung tissues from five mice in each group were collected on postnatal days 7 and 14, respectively. Histopathological changes of the lung tissues was detected by HE staining. The expression level of surfactant protein C (SP-C) in the lung tissues was examined by Western blot analysis. Flow cytometry was performed to assess the proportion of FOXP3⁺ Tregs and RORγt⁺FOXP3⁺ Tregs in CD4⁺ lymphocytes. The concentrations of interleukin-17A (IL-17A) and IL-6 in lung homogenate were measured by using ELISA. Spearman correlation analysis was used to analyze the correlation between FOXP3⁺Treg and the expression of SP-C and the correlation between RORγt⁺FOXP3⁺ Tregs and the content of IL-17A and IL-6. Results The hyperoxia group exhibited significantly decreased levels of SP-C and radical alveolar counts in comparison to the control group. The proportion of FOXP3⁺Tregs was reduced and that of RORγt⁺FOXP3⁺Tregs was increased. IL-17A and IL-6 concentrations were significantly increased. SP-C was positively correlated with the expression level of RORγt⁺FOXP3⁺ Tregs. RORγt⁺FOXP3⁺ Tregs and IL-17A and IL-6 concentrations were also positively correlated. Conclusion The number of FOXP3⁺ Tregs in lung tissue of BPD mice is decreased and converted to RORγt⁺ FOXP3⁺ Tregs, which may be involved in hyperoxy-induced lung injury.
Animals ; Mice ; Mice, Inbred C57BL ; Bronchopulmonary Dysplasia ; T-Lymphocytes, Regulatory ; Interleukin-17 ; Nuclear Receptor Subfamily 1, Group F, Member 3 ; Hyperoxia ; Interleukin-6 ; Forkhead Transcription Factors ; Lung

Objective To construct a recombinant poxvirus vector vaccine, rVTTδTK-RBD, and to evaluate its safety and immunogenicity. Methods The receptor-binding domain (RBD) gene was synthesized with reference to the gene sequence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and was inserted into the polyclonal site of the self-constructed recombinant plasmid pSTKE, to construct the recombinant poxvirus shuttle vector pSTKE-RBD. This was then transfected into BHK-21 cells pre-infected with the vaccinia virus Tiantan strain (VTT). The recombinant poxvirus rVTTδTK-RBD was successfully obtained after several rounds of fluorescence phage screening. The effect of rVTTδTK-RBD on the body mass of BALB/c mice was detected after immunizing mice by intra-nasal vaccination. The levels of specific and neutralizing antibodies produced by rVTTδTK-RBD on BALB/c mice were analyzed after immunizing mice intramuscularly. The effect of rVTTδTK-RBD on T cell subsets in BALB/c mice was detected by flow cytometry. Results Through homologous recombination, enhanced green fluorescent protein (EGFP) screening marker, and multiple rounds of fluorescent phosphorescence phage screening, a recombinant poxvirus rVTTδTK-RBD, expressing RBD with deletions in the thymidine kinase (TK) gene, was successfully obtained, which was validated by PCR. The in vivo experiments on BALB/c mice showed that rVTTδTK-RBD was highly immunogenic against SARS-CoV-2 and significantly reduced toxicity to the body compared to the parental strain VTT. Conclusion The recombinant poxvirus vaccine rVTTδTK-RBD against SARS-CoV-2 is successfully constructed and obtained, with its safety and immunogenicity confirmed through various experiments.
Animals ; Mice ; SARS-CoV-2/genetics* ; COVID-19 ; Vaccines, Synthetic/genetics* ; Genes, Reporter ; Bacteriophages ; Mice, Inbred BALB C

OBJECTIVE: To determine the role of Tripterygium wilfordii multiglycoside (TGW) in the treatment of psoriatic dermatitis from a cellular immunological perspective. METHODS: Mouse models of psoriatic dermatitis were established by imiquimod (IMQ). Twelve male BALB/c mice were assigned to IMQ or IMQ₊TGW groups according to a random number table. Histopathological changes in vivo were assessed by hematoxylin and eosin staining. Ratios of immune cells and cytokines in mice, as well as PAM212 cell proliferation in vitro were assessed by flow cytometry. Pro-inflammatory cytokine expression was determined using reverse transcription quantitative polymerase chain reaction. RESULTS: TGW significantly ameliorated the severity of IMQ-induced psoriasis-like mouse skin lesions and restrained the activation of CD45⁺ cells, neutrophils and T lymphocytes (all P<0.01). Moreover, TGW significantly attenuated keratinocytes (KCs) proliferation and downregulated the mRNA levels of inflammatory cytokines including interleukin (IL)-17A, IL-23, tumor necrosis factor α, and chemokine (C-X-C motif) ligand 1 (P<0.01 or P<0.05). Furthermore, it reduced the number of γ δ T17 cells in skin lesion of mice and draining lymph nodes (P<0.01). CONCLUSIONS TGW improved psoriasis-like inflammation by inhibiting KCs proliferation, as well as the associated immune cells and cytokine expression. It inhibited IL-17 secretion from γ δ T cells, which improved the immune-inflammatory microenvironment of psoriasis.
Male ; Animals ; Mice ; Tripterygium ; Psoriasis/drug therapy* ; Keratinocytes ; Skin Diseases/metabolism* ; Cytokines/metabolism* ; Imiquimod/metabolism* ; Dermatitis/pathology* ; Disease Models, Animal ; Mice, Inbred BALB C ; Skin/metabolism*

Multiple sclerosis (MS) is a neuroinflammatory demyelinating disease, mediated by pathogenic T helper 17 (Th17) cells. However, the therapeutic effect is accompanied by the fluctuation of the proportion and function of Th17 cells, which prompted us to find the key regulator of Th17 differentiation in MS. Here, we demonstrated that the triggering receptor expressed on myeloid cells 2 (TREM-2), a modulator of pattern recognition receptors on innate immune cells, was highly expressed on pathogenic CD4-positive T lymphocyte (CD4⁺ T) cells in both patients with MS and experimental autoimmune encephalomyelitis (EAE) mouse models. Conditional knockout of Trem-2 in CD4⁺ T cells significantly alleviated the disease activity and reduced Th17 cell infiltration, activation, differentiation, and inflammatory cytokine production and secretion in EAE mice. Furthermore, with Trem-2 knockout in vivo experiments and in vitro inhibitor assays, the TREM-2/zeta-chain associated protein kinase 70 (ZAP70)/signal transducer and activator of transcription 3 (STAT3) signal axis was essential for Th17 activation and differentiation in EAE progression. In conclusion, TREM-2 is a key regulator of pathogenic Th17 in EAE mice, and this sheds new light on the potential of this therapeutic target for MS.
Animals ; Humans ; Mice ; CD4-Positive T-Lymphocytes/pathology* ; Cell Differentiation ; Encephalomyelitis, Autoimmune, Experimental/metabolism* ; Mice, Inbred C57BL ; Multiple Sclerosis ; Th1 Cells/pathology*

Pathological vascular remodeling is a hallmark of various vascular diseases. Previous research has established the significance of andrographolide in maintaining gastric vascular homeostasis and its pivotal role in modulating endothelial barrier dysfunction, which leads to pathological vascular remodeling. Potassium dehydroandrographolide succinate (PDA), a derivative of andrographolide, has been clinically utilized in the treatment of inflammatory diseases precipitated by viral infections. This study investigates the potential of PDA in regulating pathological vascular remodeling. The effect of PDA on vascular remodeling was assessed through the complete ligation of the carotid artery in C57BL/6 mice. Experimental approaches, including rat aortic primary smooth muscle cell culture, flow cytometry, bromodeoxyuridine (BrdU) incorporation assay, Boyden chamber cell migration assay, spheroid sprouting assay, and Matrigel-based tube formation assay, were employed to evaluate the influence of PDA on the proliferation and motility of smooth muscle cells (SMCs). Molecular docking simulations and co-immunoprecipitation assays were conducted to examine protein interactions. The results revealed that PDA exacerbates vascular injury-induced pathological remodeling, as evidenced by enhanced neointima formation. PDA treatment significantly increased the proliferation and migration of SMCs. Further mechanistic studies disclosed that PDA upregulated myeloid differentiation factor 88 (MyD88) expression in SMCs and interacted with T-cadherin (CDH13). This interaction augmented proliferation, migration, and extracellular matrix deposition, culminating in pathological vascular remodeling. Our findings underscore the critical role of PDA in the regulation of pathological vascular remodeling, mediated through the MyD88/CDH13 signaling pathway.
Mice ; Rats ; Animals ; Myeloid Differentiation Factor 88/metabolism* ; Vascular Remodeling ; Cell Proliferation ; Vascular System Injuries/pathology* ; Carotid Artery Injuries/pathology* ; Molecular Docking Simulation ; Muscle, Smooth, Vascular ; Cell Movement ; Mice, Inbred C57BL ; Signal Transduction ; Succinates/pharmacology* ; Potassium/pharmacology* ; Cells, Cultured ; Diterpenes ; Cadherins

BACKGROUND: Sjögren's syndrome (SS) is an autoimmune disorder characterized by sicca syndrome and/or systemic manifestations. The treatment is still challenging. This study aimed to explore the therapeutic role and mechanism of exosomes obtained from the supernatant of stem cells derived from human exfoliated deciduous teeth (SHED-exos) in sialadenitis caused by SS. METHODS: SHED-exos were administered to the submandibular glands (SMGs) of 14-week-old non-obese diabetic (NOD) mice, an animal model of the clinical phase of SS, by local injection or intraductal infusion. The saliva flow rate was measured after pilocarpine intraperitoneal injection in 21-week-old NOD mice. Protein expression was examined by western blot analysis. Exosomal microRNA (miRNAs) were identified by microarray analysis. Paracellular permeability was evaluated by transepithelial electrical resistance measurement. RESULTS: SHED-exos were injected into the SMG of NOD mice and increased saliva secretion. The injected SHED-exos were taken up by glandular epithelial cells, and further increased paracellular permeability mediated by zonula occluden-1 (ZO-1). A total of 180 exosomal miRNAs were identified from SHED-exos, and Kyoto Encyclopedia of Genes and Genomes analysis suggested that the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) pathway might play an important role. SHED-exos treatment down-regulated phospho-Akt (p-Akt)/Akt, phospho-glycogen synthase kinase 3β (p-GSK-3β)/GSK-3β, and Slug expressions and up-regulated ZO-1 expression in SMGs and SMG-C6 cells. Both the increased ZO-1 expression and paracellular permeability induced by SHED-exos were abolished by insulin-like growth factor 1, a PI3K agonist. Slug bound to the ZO-1 promoter and suppressed its expression. For safer and more effective clinical application, SHED-exos were intraductally infused into the SMGs of NOD mice, and saliva secretion was increased and accompanied by decreased levels of p-Akt/Akt, p-GSK-3β/GSK-3β, and Slug and increased ZO-1 expression. CONCLUSION Local application of SHED-exos in SMGs can ameliorate Sjögren syndrome-induced hyposalivation by increasing the paracellular permeability of glandular epithelial cells through Akt/GSK-3β/Slug pathway-mediated ZO-1 expression.
Mice ; Animals ; Humans ; Sjogren's Syndrome/therapy* ; Proto-Oncogene Proteins c-akt/metabolism* ; Tight Junctions/metabolism* ; Glycogen Synthase Kinase 3 beta ; Mice, Inbred NOD ; Phosphatidylinositol 3-Kinases/metabolism* ; Exosomes/metabolism* ; Xerostomia ; Phosphatidylinositol 3-Kinase ; MicroRNAs/genetics*

Animals ; Mice ; Chlamydia muridarum ; Mice, Inbred BALB C ; Antigens, Bacterial ; Chlamydia Infections

The objective of present study was to develop a simple and reliable voiding spot assay (VSA) system to evaluate the lower urinary tract function of mice, and to establish it as a standardized protocol. Ultraviolet (UV) light was used to screen out the filter paper without autofluorescence and with optimal urine diffusion properties. Next, the appropriate wavelength of UV was determined based on the quality of the photographic image of urine spots on the filter paper. To confirm that the urine stain area on the filter paper was correlated with the amount of urine, a volume-area standard curve was constructed. The utility of this VSA system was validated using female wild-type C57BL/6J mice aged 12-13 weeks, and the data generated under identical procedural settings were compared among laboratories. Furthermore, this VSA system was employed to analyze the changes in voiding patterns in mice with urinary tract infections or transportation stress. No. 4 filter paper with a thickness of 0.7 mm was identified as the most suitable material for VSA, exhibiting no autofluorescence and facilitating optimal urine diffusion. The filter paper retained its integrity during the assay, and there was a linear correlation between urine volume and stained area under 365 nm UV light. Utilizing this VSA system, we determined that female wild-type C57BL/6J mice produced approximately 695.8 μL total urine and 5.5 primary voiding spots (PVS) with an average size of 126.4 μL/spot within 4-h period. Over 84% of PVS volumes ranged from 20 to 200 μL. Notably, PVS volumes of mice were similar across different laboratories. Mice with urinary tract infections or transportation stress exhibited significant changes in VSA parameters, including increased voiding frequency, PVS number, and decreased PVS volume. Therefore, this VSA system can be used to evaluate the urinary function of normal mice, as well as those with urinary tract infection or transportation stress.
Mice ; Female ; Animals ; Urodynamics ; Mice, Inbred C57BL ; Urination ; Urinary Bladder ; Urinary Tract Infections