Background: Skeletal tuberculosis (TB) remains a persistent clinical and research challenge due to its chronic course, osteolytic destruction, and the limitations of existing animal models, which often require high-level biosafety containment or fail to replicate human skeletal pathology.

Methods: This study developed a biosafe, accessible, and versatile murine model of skeletal TB using Mycobacterium smegmatis, a fast-growing, nonpathogenic mycobacterial species with high genomic homology to Mycobacterium tuberculosis. Three infection routes—subperiosteal calvarial injection, intratibial injection, and intracardiac inoculation—were systematically evaluated for their ability to induce localized versus disseminated bone infection under standard biosafety level (BSL)-1 conditions.

Results: Subperiosteal calvarial and intratibial injection of M. smegmatis induced localized bone lesions characterized by osteolysis, sequestrum formation, granulomatous inflammation, and increased osteoclast activity. Intratibial infection additionally triggered compartment-specific immune responses, including neutrophil and macrophage expansion, transient B-cell depletion, and activation of interferon-γ⁺ (IFN-γ⁺) T cells, reflecting active immune remodeling at the infection site. Systemic dissemination via intracardiac injection reproducibly generated progressive vertebral and tibial bone destruction with organized granuloma formation and immune cell infiltration but without prominent sequestrum formation. Compared to intratibial infection, intracardiac delivery exhibited lower intragroup variability and more closely recapitulated the diffuse progression of extrapulmonary skeletal tuberculosis.

Conclusions: This M. smegmatis–based murine model provides a straightforward, reliable, and immunopathologically relevant platform for exploring host–pathogen dynamics, immune-driven bone destruction, and early-stage therapeutic testing in skeletal TB, all within standard BSL-1 laboratories. This model fills a critical gap by enabling BSL-1 research into skeletal TB mechanisms and drug development.

Background: The aim was to investigate the time- and dose-related changes in the behavioral and pathological characteristics in the MIA-induced KOA model rat.

Methods: MIA (40, 50, and 60 mg/mL) was injected into the left joint of male Sprague–Dawley rats. After 2 weeks, the changes in the KOA rat model were observed by behavioral evaluation, imaging-level evaluation, and histological-level evaluation. The changes were also compared after 40-mg/mL MIA injection for 2 and 6 weeks.

Results: MIA-induced bone surface defects, osteophyte hyperplasia around the articular rim, increased subchondral bone density, thinning of the sparse trabecular bone, structural disorder, and local clustering were observed. The degree of injury gradually increased with the increase in MIA concentration. After 6 weeks, subchondral bone density and sparse trabecular bone increased in the KOA model.

Conclusions: The severity of the model also increased significantly with the changes in dose and time. In dose-dependent experiments, this study revealed that 40 mg/mL was the optimal dose to induce significant pathological changes without causing undue discomfort or death in animals. This dose may induce pathological changes stably and is suitable for long-term observation.

Background: Biological osteosynthesis preserves blood supply and promotes rapid healing by aligning fracture fragments without direct surgical exposure. Pedicle screws are primarily designed for internal fixation in spinal procedures. A key objective of many orthopedic studies is to assess the biocompatibility of implants with bone and adjacent soft tissue. This study aims to evaluate the biocompatibility and effects of the Pedicle screw-Rod configuration as a novel external fixation method in canine tibial osteotomy.

Methods: With ethics approval, eight healthy, intact male dogs, aged 10–12 months and weighing between 20 and 22 kg, underwent a minimally invasive medial tibial approach for surgical fixation of tibial osteotomy using a Pedicle screw-Rod configuration. Postoperative evaluations included ultrasound assessments at the osteotomy site and histological evaluations at the bone-screw interface.

Results: B-mode ultrasound evaluation indicated healing progress at all osteotomy sites. The color Doppler examination revealed an initial increase in signals in the surrounding soft tissue during the first 4 weeks post-operation, followed by a decrease in signals within the adjacent soft tissue between the 5th and 8th weeks. During this latter period, the signals were primarily concentrated on the bone surface and the callus. The bone-screw interface at various screw sites exhibited similar histological changes, indicating effective integration of the newly formed woven bone into the screw threads.

Conclusions: Fixation of non-articular tibial osteotomy with Pedicle screw-Rod configuration resulted in secondary bone healing, characterized by abundant callus formation and neovascularization. This implant demonstrated favorable biocompatibility with bone and surrounding soft tissue, without significant complications.

Osteoclasts are essential for maintaining healthy bone. Pathological elevation of osteoclastogenesis or osteoclast activity can cause osteoporosis and increase the risk of bone fracture. However, a few options are available for directly measuring osteoclast activity in vivo to test interventions that may affect osteoclasts. Here, we describe an in vivo method to measure osteoclast-mediated bone loss targeted at normal mouse calvaria. The method employs a novel procedure for measuring osteoclast resorption pits using micro-computed tomography. The potential utility of this mouse calvaria model to assess therapies targeting osteoclasts was validated using zoledronic acid, which is a nitrogen-containing bisphosphonate drug used to treat osteoporosis.

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death and disability worldwide. Its complex etiology involves factors such as smoking, air pollution, genetic susceptibility, and social environment. With the accelerating global aging population and urbanization, the incidence and burden of COPD continue to rise. Current treatment strategies for COPD are relatively conservative, primarily focusing on bronchodilators, inhaled corticosteroids, and long-term oxygen therapy. Although these approaches can alleviate symptoms and slow disease progression to some extent, they fail to effectively target the underlying mechanisms of the disease, leaving an unmet clinical need for more-effective therapies. This highlights the urgency of developing innovative drugs that are both safe and efficacious to address the challenges in COPD treatment. As a traditional Chinese medicine with a long history, Colla corii asini has garnered significant attention for its diverse pharmacological effects and favorable safety profile. Research has shown that Colla corii asini possesses multiple biological activities, including hematopoiesis, nourishing the lungs, enhancing immunity, anti-infection, antiaging, antitumor, and antifatigue effects. Moreover, it has demonstrated potential in regulating oxidative stress, immune imbalance, and inflammatory responses. Recent evidence suggests that Colla corii asini may play a protective role in lung function through multitarget and multipathway mechanisms. Based on previous research findings, this paper explores the potential therapeutic value of Colla corii asini in COPD treatment by addressing the current clinical management challenges and identifying potential therapeutic targets. It also integrates the pharmacological effects of Colla corii asini into a broader treatment context, providing new perspectives for comprehensive COPD management and laying the theoretical foundation for its modernization and innovative application.

Pathological scarring, manifested in the form of hypertrophic scars (HTS) and keloid scars (KS), represents a major clinical challenge due to its aesthetic and functional implications for patients. Understanding the molecular mechanisms involved in these types of scars and developing effective treatments requires the use of controlled experimental models, especially animals, to overcome the limitations of clinical studies. The aim of this sistematic review is to critically analyze the animal models used in the last five years (2020–2025) for the study of pathological scars, highlighting their advantages, limitations and applicability in the development of new therapeutic strategies. Murine, rabbit and porcine models, as well as alternative models, offer varied perspectives on the formation and treatment of HTS and KS, with an emphasis on histological and molecular correlations with human pathology. By synthesizing recent data, the paper highlights the essential role of preclinical research in optimizing antifibrotic treatments and in advancing the translation of data into the clinical sphere. Overall, animal models remain essential for bridging mechanistic insights with clinical translation, supporting the development of more effective and personalized anti-scar therapies.

The rising incidence of dementia and associated neurodegenerative disorders poses a growing public health challenge. These conditions have traditionally been studied as isolated central nervous system disorders; however, emerging evidence suggests that broader systemic factors, including chronic inflammation, immune dysregulation, metabolic dysfunction, and genetic susceptibility, may also play a role. This review examines the interconnection between autoimmune diseases and metabolic syndromes in the pathogenesis and exacerbation of neurodegeneration. Conditions such as rheumatoid arthritis, systemic lupus erythematosus, and type 1 diabetes mellitus have been associated with a heightened risk of developing dementia through chronic immune activation, blood–brain barrier disruption, and neuroinflammatory signaling. Similarly, metabolic disorders such as diabesity promote insulin resistance and oxidative stress, accelerating cognitive decline. The review also discusses glaucoma as a neurodegenerative condition with autoimmune features, underscoring the need for expanded classification and treatment strategies. A key focus is the utilization of the Collaborative Cross (CC) mouse model, which enables the study of gene–environment interactions across genetically diverse backgrounds. Findings from CC mice reveal strain-dependent susceptibility to inflammation, cognitive impairment, and gut–brain axis dysfunction, providing a translational bridge to human variability. This review highlights the importance of integrating precision-based approaches to dementia research that consider systemic influences. Advancing our understanding of these multiorgan interactions holds potential for designing precision-based therapeutic approaches to postpone the onset or reduce the incidence of neurodegenerative conditions.

Background: This study investigated the role of polydatin in regulating macrophage–epithelial cell (EC) interactions during asthma. An asthma model was induced in BALB/c mice using ovalbumin (20 μg).

Methods: The therapeutic effects of polydatin (20 and 40 mg/kg) were evaluated in this asthmatic mouse model. To assess the underlying mechanisms, Bronchial Epithelium Adenovirus 12-SV40 2B (BEAS-2B) cells were cocultured with Tohoku Hospital for Pediatrics-1 (THP-1) macrophages, in which toll-like receptor 4 (TLR4) was either overexpressed or knocked down, and subsequently stimulated with lipopolysaccharide (LPS) and ATP. THP-1 cells underwent a 1-h pretreatment with polydatin (50 and 100 μmol/L), Class Lipid Inhibitor-095 (CLI-095, TLR4 inhibitor, 1 μg/mL), or A438079 (P2X7R antagonist, 10 μmol/L) prior to LPS/ATP challenge.

Results: Findings from Western blotting, enzyme-linked immunosorbent assay, flow cytometry, real-time polymerase chain reaction, and immunofluorescence assays demonstrated that modulating TLR4 expression significantly altered interleukin-1β (IL-1β) secretion from THP-1 macrophages and mitochondrial reactive oxygen species (mtROS) production in BEAS-2B ECs. In the mouse asthma model, polydatin significantly alleviated airway inflammation, oxidative stress, and apoptosis, likely by interfering with TLR4/P2X7R-mediated signaling and suppressing the activation of the NOD-like receptor protein inflammasome. Additionally, polydatin significantly reduced IL-1β and IL-18 levels and inhibited the infiltration of macrophages and eosinophils. Correspondingly, polydatin significantly attenuated TLR4/P2X7R signaling in THP-1 cells stimulated with ATP and LPS, thereby reducing IL-1β and IL-18 secretion, calcium influx, mtROS production, and apoptosis in BEAS-2B ECs.

Conclusions: Polydatin is a promising therapeutic candidate for asthma, possibly by targeting macrophage–epithelium cross-talk via the TLR4/P2X7R axis. Future formulations as capsules or sprays may effectively alleviate airway inflammation and remodeling.

Background: In recent decades, the global incidence of dengue fever has been steadily increasing, with continuous geographical expansion. Researchers have successfully modeled most clinical symptoms of human dengue fever using interferon type I (IFN-I) or combined IFN-I/II receptor knockout mice infected with dengue virus (DENV). However, this model requires further optimization to better support related studies.

Methods: This study aimed to establish a stable dengue infection model by evaluating the effects of different genetic backgrounds and injection routes on DENV infection in interferon receptor knockout mice. We first infected various strains of interferon receptor-deficient mice with DENV and compared their susceptibility based on clinical symptoms, viremia levels, organ indices, histopathological findings, and vascular leakage markers. Subsequently, we selected the most susceptible strain to further investigate the impact of different injection methods on infection outcomes.

Results: We found that BALB/c background mice with type 1 interferon receptor knockout(IFNAR) had the most obvious symptoms. Subsequently, we selected IFNAR−/−BALB/c mice to further explore the effects of different injection methods on dengue virus infection. The results showed that the intraperitoneal injection group had the most severe clinical symptoms, the longest duration of viremia, and the most obvious degree of organ damage.

Conclusion: Through systematic screening and optimization, we established a robust animal model of dengue virus infection via intraperitoneal injection in IFNAR−/− BALB/c mice. This model offers a valuable tool for future dengue research.

Background: Triptolide (TP) exhibits various pharmacological activities. Our previous studies have confirmed the efficacy of TP against lung adenocarcinoma (LUAD). However, the potent pharmacological activity of TP is underpinned by its complex mechanisms. Exploring its potential mechanisms is of great value for promoting the clinical application of TP and extending its clinical use.

Methods: Differentially expressed genes (DEGs) associated with LUAD were analyzed and acquired from the TCGA database, while DEGs related to TP were obtained through RNA sequencing. Hub genes were identified through LASSO and random forest models. The efficacy of TP against LUAD was validated using tumor-bearing mouse models and A549 cells. The validation of hub genes was conducted using RT-qPCR. The regulatory effect of hub genes on TP efficacy was validated through overexpression cell models. Furthermore, the potential mechanisms by which TP improves gemcitabine (GEM) resistance were explored using a GEM-resistant cell line in combination with the overexpression model.

Results: This study validated the therapeutic effect of TP against LUAD in vivo and in vitro. Bioinformatics revealed that the mechanism of TP's effect against LUAD might be associated with amino acid-related biological processes. Five hub genes were screened and identified by combining bioinformatics methods and experiments. The overexpression model validated that PSAT1 plays an effective role in the efficacy of TP and in alleviating GEM resistance.

Conclusion: This study preliminarily demonstrated that the anti-LUAD effect of TP was associated with the PSAT1-regulated serine biosynthesis pathway, and that TP effectively improves GEM resistance by inhibiting PSAT1 expression.

Background: Targeted delivery of biological macromolecules to the small intestine remains challenging due to their susceptibility to degradation in the hostile gastric environment.

Methods: This study introduces a minimally invasive, in situ injection technique for the murine small intestine that facilitates localized luminal delivery while circumventing gastric barriers. The procedure involves a small abdominal incision for direct injection into the duodenum near the pylorus. Postsurgical monitoring of physiological parameters, systemic inflammatory markers, liver function, and intestinal integrity was conducted over 72 h. Histopathological analysis was performed. The delivery of the functional protein TAT-EGFP (Tat protein fused to enhanced green fluorescent protein) to intestinal epithelial cells was evaluated and compared with oral gavage. As a proof of concept, single-cell RNA sequencing of the intestinal epithelium was performed after high-mobility group box 1 administration.

Results: Postsurgical monitoring indicated only transient, anesthesia-related hypothermia and minor behavioral alterations. No significant changes were observed over 72 h in body weight, core temperature, clinical severity scores, systemic inflammatory markers (C-reactive protein and leukocytes), liver function (alanine aminotransferase), or intestinal integrity. Histopathological analysis confirmed preserved tissue architecture and normal digestive, absorptive, and barrier functions. The model successfully delivered TAT-EGFP to intestinal epithelial cells, an outcome not achievable via oral gavage due to gastric degradation. Single-cell RNA sequencing of the intestinal epithelium after high-mobility group box 1 administration revealed inflammatory gene expression patterns in specific epithelial subpopulations.

Conclusions: Compared to traditional methods such as oral gavage or organoid culture, this technique offers precise, degradation-resistant delivery of macromolecules in a physiological context. The model's versatility makes it a powerful platform for intestinal research, with applications in drug delivery assessment, gene therapy evaluation, and host–microbiota interaction studies.

Background: This study aims to explore the establishment of an animal model of cardiac injury induced by trimethylamine-N-oxide (TMAO), a metabolite secreted by gut microorganisms, and to investigate its application in moderate-intensity continuous training (MICT) intervention.

Methods: C57BL6/J mice were randomly divided into four groups: normal mice (Nor, n = 15); mice administered TMAO (TMAO, n = 15); mice undergoing (Nor+MICT, n = 15); mice undergoing (MICT) and administered TMAO (TMAO+MICT, n = 15). Mice in the TMAO and TMAO+MICT groups received daily gavage of high-dose TMAO for 8 weeks, whereas those in the Nor+MICT and TMAO+MICT groups underwent MICT for 8 weeks (60 min per session, 5 days per week, at 50% maximal running capacity). Cardiac function was evaluated using ultrasound, myocardial histology was examined using hematoxylin and eosin (HE) staining, and nuclear magnetic resonance (NMR)-based metabolomics was employed for multivariate statistical and metabolic pathway analyses.

Results: Relative to the Nor group, TMAO-treated mice exhibited significant weight loss, elevated heart rate, and reduced ejection fraction and left ventricular fractional shortening, indicating cardiac impairment. Importantly, the TMAO+MICT group demonstrated significant improvements in these parameters compared to the TMAO group, alongside distinct alterations in myocardial metabolic profiles. TMAO altered five metabolic pathways relative to controls, whereas MICT induced significant changes in three pathways in TMAO-treated mice.

Conclusion: Eight weeks of high-dose TMAO administration induced significant cardiac dysfunction in mice, which was effectively mitigated by MICT intervention. Consequently, this animal model serves as a valuable tool for investigating the mechanisms underlying the impact of MICT on cardiovascular diseases.

Background: Mastitis seriously affects the mammary health of humans and animals. Studies have found that inflammation and oxidative stress play key roles in the occurrence and development of mastitis. Therefore, in-depth research on related molecular mechanisms is of great significance.

Methods: Postpartum mice were anesthetized with pentobarbital and administered lipopolysaccharide to develop the mouse mastitis model. Proteomic analysis was performed to compare protein expression in mitochondria-associated endoplasmic reticulum membranes (MAM) from two mouse mammary gland groups. Western blot was used to detect the expression of MAM-related proteins in mitochondria. AlphaFold3 was used to predict the molecular structures of phosphofurin acidic cluster sorting protein 2 (PACS2) and mitofusin 2 (MFN2) and their interaction levels. The MFN2–PACS2 interaction was investigated using co-immunoprecipitation and small interfering RNA.

Results: The results showed that the inflammation level in the mammary gland tissue of mice with mastitis significantly increased, the total antioxidant capacity decreased, and the expression of MAM-related proteins MFN2 and PACS2 was significantly downregulated. In cell experiments, overexpression of MFN2 can inhibit inflammation and oxidative stress responses, and promote the interaction between MFN2 and PACS2 to affect the formation of MAMs.

Conclusion: In summary, this study suggests that mastitis can alter the expression of MAM–related proteins in mouse breast tissue. The interaction between MFN2 and PACS2 regulates the formation of MAMs. Overexpression of MFN2 can promote the formation of MAMs and inhibit inflammation and oxidative stress response in mammary epithelial cells. Our results provided a new theoretical basis and potential therapeutic targets for the prevention and treatment of mastitis.

Background: Rats are often used to prepare skin defect models. However, the skin defect sizes of the models prepared by researchers are different, and the lack of consensus on the critical-size defect makes it difficult to compare their research results.

Methods: The time for wound closure was evaluated and recorded through gross observation. The regression equation between the healing time and the diameter of skin defect was established, which can be used to predict the healing time for a certain skin defect size in rats. Histochemical and immunohistochemical staining was used to observe the regeneration and reconstruction of skin appendages, and the functional skin repair was quantitatively scored.

Results: The critical-size defect of rats was determined based on the maximum capacity of structural skin repair, and the functional skin repair was quantitatively scored based on the regeneration and reconstruction of skin appendages. The allowable range of critical-size skin defect of SD rats lies between 45 and 50 mm in diameter. The concept of structural repair and the category of functional repair of injured skin are put forward. The regression equation between the structural skin healing time and defect diameters is established.

Conclusion: The allowable range of skin critical-size defect of SD rats lies between 45 and 50 mm in diameter. The regression equation between the structural skin healing time and defect diameters can be used to predict the healing time for a certain skin defect size in rats.

Background: Ex vivo lung perfusion (EVLP) has emerged as a critical technique for lung preservation and evaluation prior to transplantation. While conventional rat EVLP systems utilize closed-loop dual cannulation of pulmonary artery (PA) and vein, the effect of the simplified model using single PA cannulation with passive venous drainage is unknown.

Methods: We developed two EVLP models in rats: a semi-closed circuit with PA-only cannulation and left atrial incision for passive venous drainage (SC-EVLP), and a closed circuit employing both arterial and venous cannulation (C-EVLP). Donor lungs were perfused for a defined duration and subsequently orthotopically transplanted. We evaluated pulmonary function parameters, histopathological injury scores, inflammatory cytokine levels, and apoptotic marker expression at the end of perfusion and posttransplantation.

Results: Compared to the conventional EVLP, the SC-EVLP group exhibited significantly lower PA pressure and improved dynamic lung compliance throughout perfusion. Although the levels of tumor necrosis factor-α in the perfusate were higher in the SC-EVLP group, other cytokine levels in the perfusate and bronchoalveolar lavage fluid exhibited no significant differences. Pulmonary edema was reduced in the SC-EVLP group, as indicated by a lower lung wet-to-dry ratio. After transplantation, lungs from the SC-EVLP group exhibited lower histological injury scores, reduced apoptosis, and decreased serum cytokine levels, suggesting attenuated inflammation and tissue damage.

Conclusions: In a rat model, single PA cannulation with passive venous drainage reduced pulmonary edema during EVLP and reduced lung injury and systemic inflammation after transplantation.

Background: The aim of the study was to develop a non-human primate model of metabolic dysfunction in Macaca fascicularis using chronic high-fat diet (HFD) to mimic clinical disease progression.

Methods: Thirty-five male macaques aged 10–15 years underwent an 18-month HFD intervention. Physiological parameters (BMI, BP, hematology), liver fat fraction (evaluated by ultrasound/MRI), cardiac function (assessed by echocardiography), and histopathology (using liver biopsy) were measured before and after the intervention. Serum proteomics with KEGG/STRING analyses identified molecular mechanisms.

Results: Within 6 months, HFD induced dyslipidemia (elevated TG, TCHO, HDL-C, LDL-C). After 18 months, metabolic dysfunction-associated steatohepatitis (MASH) was confirmed by histopathology in 57.14% (16/28) of macaques, diabetes (elevated FPG/HbA1c) in 17.86% (5/28), and myocardial hypertrophy (elevated LVMass/LAD) in 46.43% (13/28). Proteomics identified Bile acid-CoA: amino acid N-acyltransferase (BAAT) as a MASH hallmark protein, the level of which was inversely correlated with the degree of fibrosis. For diabetes, citrate synthase (CS) and malate dehydrogenase 1 (MDH1) impaired glucose oxidation via the TCA cycle, while hexose-6-phosphate dehydrogenase (H6PD) disrupted gluconeogenesis. Myocardial hypertrophy was associated with the downregulation of SRC proto-oncogene, non-receptor tyrosine kinase (SRC), mitogen-activated protein kinase 14 (MAPK14), emerin (EMD), and integrin subunit beta 1 (ITGB1).

Conclusions: An 18-month HFD successfully established a translational M. fascicularis model replicating key metabolic disorders (MASH, diabetes, cardiac hypertrophy). BAAT, CS/MDH1/H6PD, and SRC/MAPK14/EMD/ITGB1 were identified as mechanistic biomarkers for these conditions.

Background: In preclinical research, tumor growth inhibition in subcutaneous models is frequently employed to evaluate therapeutic efficacy; however, such models often lack clinical translatability.

Methods: To better approximate clinical reality, taking the case of doxorubicin treatment, we utilized an orthotopic transplant and resection (OtR) strategy to systematically assess the effects of neoadjuvant chemotherapy, adjuvant chemotherapy, and their combination on tumor growth, recurrence, and malignant progression.

Results: Surprisingly, none of the treatments improved mouse survival, with adjuvant therapy even shortening it. Although neoadjuvant chemotherapy delayed preoperative tumor growth, and all regimens reduced recurrence rates, none effectively prevented metastasis. Furthermore, all treatment groups exhibited weight loss, indicative of chemotherapy-induced cachexia.

Conclusions: Collectively, these findings demonstrate that reduced tumor growth in preclinical mouse models does not necessarily translate into overall survival benefit. Our results emphasize the critical importance of prioritizing metastasis prevention over tumor growth inhibition as a key efficacy endpoint in antitumor drug evaluation.