Abstract: Objective To explore the correlation between aging and idiopathic pulmonary fibrosis (IPF) and reveal the underlying molecular mechanisms. Methods IPF models were established using young (2-month-old) and aged (18-month-old) C57BL / 6J mice by intratracheal instillation of bleomycin (BLM) hydrochloride (2. 5 mg / kg) after fully exposing the trachea. The control groups received an equal volume of saline administered in the same manner. Mice were divided randomly into four groups: a young control (Ctrl-Y)group, young model (IPF-Y) group, aged control ( Ctrl-A) group, and aged model ( IPF-A) group. Histopathological changes were evaluated by hematoxylin-eosin and Masson staining. Collagen type Ⅰ alpha 1 chain (COL1A1), α-smooth muscle actin (SMA),and fibronectin ( FN ) expression were detected by immunohistochemistry. Cell senescence was detected by senescence-associated beta-galactosidase ( SA-β-Gal ) staining. Differentially expressed genes were detected by transcriptome sequencing, followed by gene ontology functional annotation(GO) and kyoto encyclopedia of genes and genomes ( KEGG) pathway enrichment analysis. Core gene expression was validated by quantitative reverse transcription-polymerase chain reaction. Results The fibrosis score was significantly higher in the IPF-A group compared with the IPF-Y group (P<0. 05). Expression levels of α-SMA, and FN were significantly upregulated in the IPF-A group versus the IPF-Y group by 36%, and 25%, respectively (P<0. 05). The SA-β-Gal-positive area indicating senescence was significantly larger in the IPF-A group than in the IPF-Y group. Fifty-five senescence-IPF interactive genes were identified, among which Cdkn1a, MMP3, and Pdcd1 were synergistically upregulated in the IPF-A group (P<0. 05). KEGG analysis revealed the activation of signaling pathways such as extracellular matrix (ECM)-receptor interaction, phagosome, cytokine-cytokine receptor interaction, efferocytosis, and PI3K-Akt (FDR<0. 05). Conclusions aging promotes IPF progression, which induces lung tissue senescence. The underlying mechanism may involve ECM remodeling driven by immunosenescence, inflammatory accumulation, and metabolic disorders.

Abstract: Objective To investigate the effect and potential mechanism of rat mesenchymal stem cells (MSC) on D-galactose-induced brain-tissue aging. Methods A rat brain-aging model was established by injecting D-galactose, and rats in the treatment group received MSC injections via the tail vein. Superoxide dismutase (SOD) activity and malondialdehyde ( MDA) levels were assessed in rat brain tissue at the end of the experiment, and pathological changes in brain tissue were observed by hematoxylin-eosin ( HE) staining. Expression levels of the inflammatory factors interleukin (IL)-1 and IL-6, the pathway proteins brain-derived neurotrophic factor (BDNF)- tropomyosin receptor kinase B (TrkB), the negative growth regulators p53 and p16, as well as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) were observed by polymerase chain reaction (PCR) and Western Blot. Results Brain levels of SOD activity were significantly increased and MDA levels were significantly decreased in rats in the modle group compared with the treatment group (P<0. 05). The pathological state of the cerebral cortex and hippocampus were improved and the number of neurons and nucleus pulposus ratio in the brain were increased in the treatment group, as shown by HE staining. Expression levels of IL-1, IL-6, p53, and p16 were significantly decreased, while BDNF, TrkB, VEGF, and bFGF were significantly increased in the treatment group compared with the model group, as shown by PCR and Western Blot (P<0. 05). Conclusions These result suggest that MSCs potentially mitigate D-galactose-induced cerebral senescence by concurrently modulating the BDNFTrkB axis to attenuate oxidative / inflammatory damage, while enhancing the secretion of vasculotrophic (VEGF) and neurotrophic (bFGF) factors for neuronal maintenance.

Abstract: Objective To explore the effect of Rhizoma Polygonati (RP) on arterial aging in naturally agingWistar rats. Methods SPF Wistar rats aged 72 weeks were divided randomly divided into 4 groups: an old group and RP low, medium, and high-dose groups (n = 14 rats per group). Another 14 male SPF Wistar rats aged 8 ~ 12 weeks were selected as the young group. Rats in the RP high, medium, and low-dose groups were administered with 4, 2, and 1 g / kg RP, respectively, by gavage, and rats in the old and young groups were given the same amount of distilled water once a day for 12 weeks. Seven rats from each group were sacrificed under anesthesia at weeks 4 and 12 and aortas were isolated. The relative smooth muscle cell (SMC) and collagen fiber (CF) contents were analyzed, total antioxidant capacity ( T-AOC ), glutathione peroxidase ( GSH-Px ), superoxide dismutase ( SOD), and malondialdehyde (MDA) levels were measured, and the expression levels of cell cycle-associated proteins in arterial tissue were detected by Western Blot. Results Rats in the old group showed obvious signs of vascular aging but there was no significant changes in arterial vascular tissue indexes in the old group with increased age. Aortas were obviously injured, relative contents of SMC and CF were significantly increased (P<0. 01), T-AOC, SOD, and GSH-Px contents were significantly decreased and MDA was increased (P<0. 01) in the old group compared with the young group at 4 and 8 weeks, and expression levels of cell cycle-associated proteins were significantly upregulated (P<0. 01). RP intervention significantly decreased the relative SMC and CF contents and MDA levels (P<0. 05 or P<0. 01) and significantly increased T-AOC,SOD,and GSH-Px (P<0. 05 or P<0. 01). Expression levels of cell cycle-associated proteins were also significantly decreased (P<0. 05 or P<0. 01). High-dose RP had the greatest effect. Conclusions Arterial aging is relatively stable in the short term in naturally aging rats. RP could delay arterial aging in naturally aging rats by regulating the level of oxidative stress and the expression of cell cycleassociated proteins.

Abstract: Objective To compare the effects of different doses of adenine (ADE) by oral gavage in a mouse model of renal fibrosis (RF), and to provide a more suitable mouse model for further RF research. Methods Thirty C57BL / 6J Nifdc mice were divided randomly into a control group, low-dose ADE group (ADE-L group, 50 mg / kg),and high-dose ADE group ( ADE-H group, 100 mg / kg), and the general condition, mortality, and body mass changes of the mice were observed. Serum creatinine (CREA), blood urea nitrogen (BUN), and uric acid (UA) were measured on day 30 to evaluate renal function. Histopathological changes in kidney tissues were observed by hematoxylin-eosin (HE) and Masson staining, and expression levels of fibronectin (FN), collagen Ⅰ (COL Ⅰ),and alpha smooth muscle actin (α-SMA) in kidney tissues were detected by Western Blot. Results The cumulative mortality rates in the ADE-L and ADE-H groups were 91. 7% and 58. 3%, respectively. The body mass of mice in the ADE-L group was similar to that in the control group (P>0. 05), but the body mass of mice in the ADE-H group was significantly lower than that of mice in the control and ADE-L groups from day 3 to day 30 (P<0. 001). Day 30 CREA and BUN levels in the ADE-L group were similar to those in the blank group, but CREA and BUN levels were significantly increased in the ADE-H group (P<0. 001). There were no significant differences in UA levels among all groups. Inflammatory infiltration and tubular dilatation were observed in the ADE-L group on day 30, accompanied by tubular epithelial necrosis, while crystal accumulation in the tubular lumen and interstitium was observed in the ADE-H group, and the degree of interstitial fibrosis was significantly higher than in the control group (P<0. 01).Expression levels of interstitial fibrosis-related proteins in the ADE-H group on day 30 were significantly higher than in the control and ADE-L groups (P<0. 05, P<0. 01 or P<0. 001). Conclusions Both 50 and 100 mg / kg of ADE can be used to establish a mouse model of RF, with different doses leading to varying degrees of renal injury. Mice in the ADE-L group developed mild interstitial fibrosis on day 30, while mice in the ADE-H group developed moderate to severe interstitial fibrosis.

Abstract: Objective To establish and evaluate a mouse model of chronic obstructive pulmonary disease (COPD) induced by cigarette smoke (CS). Methods Forty BALB/ c mice were divided randomly into a control group and a CS group. Mice in the CS group were subjected to passive smoking for 20 weeks and a COPD model was established. Morphological changes in the organs and lung, heart, liver, and kidney fibrosis were observed by hematoxylin-eosin ( HE) and Masson staining. Lung, cardiac, and brain cognitive function were evaluated by pulmonary function testing, small-animal ultrasound, and Morris water maze trials. Tumor necrosis factor-α ( TNF-α), interleukin (IL)-6 and IL-1β levels in lung and brain tissues were detected by ELISA. Liver and renal functions were measured by biochemical method. Results The alveolar septum was narrowed or broken in mice in the CS group, and the adjacent alveolar cavity was enlarged and fused, consistent with the pathological changes of COPD. Neuronal degeneration and necrosis were observed in the hippocampus, but there were no significant morphological changes in other organs. Masson staining showed no obvious fibrosis in the lung, heart, liver, or kidney in CS-group mice. The result of pulmonary function tests showed that the forced expiratory volume in 0. 1 second / forced vital capacity(FEV 0. 1 / FVC) and dynamic compliance were significantly decreased in the CS group compared with the control group, while airway resistance was obviously increased. Cognitive impairment in mice in the CS group was confirmed in the Morris water maze trial. TNF-α, IL-6, and IL-1β levels in lung and brain tissues were higher in the CS group compared with the control group. There were no significant differences in cardiac, liver, and renal functions between the groups. Conclusions A mouse model of COPD can be established by CS exposure for 20 weeks. Lung histomorphology, lung function, brain cognitive function, and levels of inflammatory factors can be used as indicators to evaluate the success of the model.

Abstract: Objective To investigate the effects of m6A methylation modification and changes in oxidative stress levels on the progression of colorectal cancer (CRC) in Apc ^{min/ +}mice with normal and high-fat diets. Methods C57BL / 6J mice and Apc ^{min/ +} mice were fed with a normal or high-fat diet (60% fat) for 2 (S group), 6 (M group),or 12 weeks (L group), respectively. Food intake, body mass, and the size, number, and volume of small intestinal polyps and colon tumors were then measured. Protein expression levels of the cancer markers Ki-67 and proliferating cell nuclear antigen in colon tissues were detected by immunohistochemical staining and the serum levels or activities of the antioxidant enzymes catalase, reduced glutathione, and lipid peroxide malondialdehyde were detected using appropriate kits. mRNA expression levels of m6A methylation-related enzymes in colon tissues were detected by RTqPCR and total levels of m6A methylation modification in colon tissues were detected. Results (1) Apc ^{min/ +} mice showed rapid tumor growth from the early to middle stages of cancer. Tumor proliferation from the middle to late stages of cancer was slowed in mice fed a normal diet, while a high-fat diet promoted the further development of cancer. (2) Decreased m6A methylation levels and enhanced antioxidant capacity may have delayed advanced tumor development in Apc ^{min/ +}mice fed a normal diet. (3)In contrast, a high-fat diet may have promoted the sustainable development of CRC by increasing the total level of m6A methylation, while the enhanced antioxidant capacity may have been insufficient to resist the promoting effect of m6A methylation on CRC. Conclusions A high-fat diet may promote the advancement of CRC compared with a normal diet by affecting m6A methylation modification. Both normal and highfat diets enhanced the antioxidant capacity,suggesting that antioxidant effects may initiate self-protection mechanisms during cancer progression.

Abstract: Objective To establish atopic dermatitis ( AD)-like models in BALB/ c mice using three chemical inducers, calcipotriol ( MC903), 2, 4-dinitrochlorobenzene ( DNCB), and oxazolone ( OXA), and to explore the occurrence of ferroptosis in the different models. Methods Healthy 7-week-old female BALB/ c mice were divided randomly into eight groups (n = 8 mice per group) based on the induction site (ear/ dorsal skin) and inducer: ear/ dorsal control groups, MC903 ear/ dorsal model groups, DNCB ear/ dorsal model groups, and OXA ear/ dorsal model groups. Models were established by topical application of the respective agents at specified concentrations. Mice in the MC903 ear/ dorsal groups underwent continuous induction for 14 d. Mice in the DNCB and OXA ear/ dorsal groups were sensitized for 3 consecutive days, 4 days after the sensitization was completedand then challenged 12 times on day 8 and every other day for up to day 30. Skin lesions were observed and skin thickness was measured. Plasma levels of reactive oxygen species ( ROS), interleukin ( IL)-4, interferon ( IFN)-γ, and malondialdehyde ( MDA) were detected, the skin was examined by histopathological staining and ultrastructural observation, and expression levels of ferroptosis-related proteins ( glutathione peroxidase 4 (GPX4), ferritin heavy chain 1 (FTH1), long-chain-fatty-acid-CoA ligase 4 (ACSL4), transferrin receptor 1 ( TfR1)) were detected by Western Blot. Results Compared with each control mice, all model mice exhibited obvious redness, swelling, scratching, desquamation, and rough thickening of the skin, and skin thickness was significantly increased ( P<0. 01). ROS, IFN-γ, IL-4, and MDA levels were elevated to varying extents ( P<0. 05) and histopathological features, including epidermal hyperplasia, keratinocyte degeneration, dermal vascular congestion, and immune cell infiltration, were detected in model mice. Transmission electron microscopy also revealed mitochondrial membrane rupture, increased density, and cristae reduction. Expression levels of ferroptosis markers were dysregulated, including significantly decreased GPX4 / FTH1 ( P<0. 05) and increased ACSL4 / TfR1 expression ( P<0. 05). Conclusions All three chemicals successfully induced AD-like phenotypes in BALB/ c mice through site-specific applications. Ferroptosis is involved in the pathological process of AD, but heterogeneity exists among inducers and modeling sites.

Abstract: Objective To investigate anxiety- and depression-like behaviors in Cynomolgus monkeys with type 2 diabetes mellitus ( T2DM ), and to explore their correlations with biochemical parameters. Methods Cynomolgus monkeys were divided into a T2DM group (fasting plasma glucose (FPG) ≥ 5. 6 mmol / L) and control group (FPG < 4. 2 mmol / L) ( n = 3 per group). Age, sex, body mass, body mass index( BMI), FPG, blood lipids, atherosclerosis index ( AI), and tumor necrosis factor-α ( TNF-α) levels were measured in both groups. Anxiety-like behaviors were assessed using the human intrude test ( HIT) and depression-like behaviors were evaluated using the apathy feeding test ( AFT). Relationships between behavioral parameters and biochemical /inflammatory markers were evaluated using Pearson’ s correlation analysis. Results ( 1) FPG, AI, and TNF-αlevels were significantly elevated while high-density lipoprotein cholesterol levels were reduced in the T2DM group compared with the control group (P<0. 05). (2) Regarding the HIT result, the durations of anxious (stare phase) and back-of-cage (stare phase) behaviors were higher in the T2DM group than in the control group (P<0. 05), while the durations of locomotor behaviors (baseline phase, profile phase, back phase) were significantly shorter (P<0. 05). ( 3) The AFT revealed that food retrieval latency was significantly delayed in the T2DM group ( P<0. 05). Pearson’s analysis identified a positive correlation between back-of-cage (stare phase) duration and AI (r=0. 828, p= 0. 042), while locomotion during the back phase showed a negative correlation with AI (r= -0. 842, p= 0. 035). Conclusions Cynomolgus monkeys with T2DM display distinct anxiety- and depression-like behavioral phenotypes, with a significant association between the AI and anxiety-related behaviors. These findings provide novel insights into the pathophysiological mechanisms linking T2DM with neuropsychiatric comorbidities.

Abstract: Objective To investigate the effect of esketamine on astrocyte activation in the spinal dorsal horn of mice with chronic pain and evaluate its impact on Wnt / β-catenin signaling. Methods Forty C57BL / 6J mice were randomly divided into five groups: sham surgery (sham) group, pain model (model) group, low-dose esketamine (LEs) group, medium-dose esketamine (M-Es) group, and high-dose esketamine (H-Es) group. Except in the sham group, chronic pain was induced via sciatic nerve branch selective injury. Each group received the designated treatment. Mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were measured. Spinal cord expression of glial fibrillary acidic protein (GFAP) was evaluated by immunohistochemistry. Immunofluorescence was used to assess astrocyte activation in the dorsal horn. Enzyme-linked immunosorbent assays measured levels of interleukin-1β(IL-1β), interleukin-6(IL-6), and tumor necrosis factor-α (TNF-α) in the spinal cord. Quantitative reverse transcription polymerase chain reaction( qRT-PCR) was performed to analyze mRNA expression patterns of Wnt3a, β-catenin, and Cyclin D1. Protein expression levels of Wnt3a, β-catenin, and Cyclin D1 in the spinal cord were evaluated by Western Blot. Results Compared with the sham group, mice in the model group showed significantly reduced MWT and TWL ( both P<0. 001). Levels of interleukin-1β, interleukin-6, and TNF-α, as well as expression of GFAP protein, were substantially increased (all P<0. 001); co-expression was evident between GFAP and Iba-1. mRNA and protein expression levels of Wnt3a, β-catenin, and Cyclin D1 were also significantly elevated (all P<0. 001). Compared with the model group, mice in all esketamine dose groups exhibited significantly increased MWT and TWL,and there was a dose-dependent effect (all P<0. 001). Levels of IL-1β, IL-6, TNF-α, and GFAP protein expression were significantly reduced (P<0. 05), co-expression of GFAP and Iba-1 was absent, and the mRNA and protein expression levels of Wnt3a, β-catenin, and Cyclin D1 were significantly decreased (P<0. 001). Conclusions Esketamine inhibits astrocyte activation and the inflammatory response, reducing chronic pain. The mechanism may involve regulation of Wnt / β-catenin signaling.

Abstract:Chronic obstructive pulmonary disease (COPD) is a common but preventable and treatable lung disease characterized by persistent airflow limitation. Comorbidities related to COPD have recently received widespread attention because of their serious effects on the quality of life and prognosis of patients, and their role in promoting the malignant development of COPD. Experimental animal models provide a key for studying the pathogenesis of COPD and its related comorbidities and for exploring effective treatment Methods. This review summarizes the modeling Methods and research progress into experimental animal models of COPD-related comorbidities, to provide references and guidance for future clinical research and screening of animal models of related comorbidities.

Abstract:Mice have been widely used in the study of primary liver cancer owing to the close similarity of its genome to that of humans, its strong reproductive ability, the low cost of model construction, and the ease of genetic manipulation, including molecular mechanisms of pathogenesis and potential drug targets. Traditional animal models are increasingly falling short of meeting the needs of precision medicine research because of their inability to reproduce tumor microenvironment interactions and control the specificity of molecular subtypes. This study systematically compared the technical advantages of tail vein high-pressure injection, combined with transposon system (HTVI-TS), with traditional models in liver cancer research, and focused on the application value of the HTVI-TS model in the mechanism study of tumorigenesis and development, immunotherapy response prediction, and individualized evaluation of targeted drugs. This report presents a new research platform for precise diagnosis and treatment of primary liver cancer by simulating the heterogeneous evolution process of the cancer. The findings provide a theoretical basis for optimizing the selection of preclinical research models for liver cancer; the expansion potential of this technology in liver cancer research is outlined.

Abstract:Aging is an inevitable biological process in organisms, accompanied by the decline of multiple physiological functions and increased risk of diseases. With the intensification of global aging, the research associated with mechanisms and the development of anti-aging drugs have become critical topics in the biomedical field. Aging animal models are pivotal tools for investigating aging mechanisms and developing anti-aging interventions. Model organisms commonly used in aging research include nematodes ( Caenorhabditis elegans), fruit flies ( Drosophila melanogaster), mice (Mus musculus), rats (Rattus norvegicus), naked-mole-rats ( e. g. , Heterocephalus glaber),and rhesus macaques (Macaca mulatta). Considering experimental costs and time constraints, mice represent the most extensively employed mammalian model. Under standard housing conditions, mice develop aging phenotypes at approximately 18 months of age, Results ing in lengthy and costly experimental timelines. To accelerate research, scientists have established diverse progeroid mouse models through genetic, pharmacological, and environmental interventions. Given the tissue-specific heterogeneity of aging, distinct progeria models are required to investigate aging mechanisms across different organ systems. Notably, each model exhibits unique advantages and limitations in mimicking human aging phenotypes, screening therapeutic targets, and evaluating anti-aging compounds. This review comprehensively examines morphological, physiological, and pathological variations among established progeria models, delineates their context-dependent applications and inherent constraints, and provides a systematic framework for model selection in fundamental aging research and translational geroscience, with perspectives on future method ological developments.

Abstract:Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease characterized by progressive scarring of the lung parenchyma, often result ing in death from respiratory failure in its terminal stages, with a median survival of only 3 to 5 years. Experimental models are essential tools for investigating the pathogenesis of IPF,screening potential drugs, and evaluating therapeutic efficacy. In addition to animal and cell models, the recent development of precision medicine and multi-omics technologies has increased attention on the need to establish models that integrate traditional Chinese medicine ( TCM) syndromes with disease patterns, as well as emerging organoid models. IPF experimental models have evolved from simulating a single pathological aspect to multidimensional models that integrate genetic heterogeneity, microenvironment interactions, and the TCM pathophysiological mechanisms of “ phlegm, stasis, deficiency, and collateral damage ”. This systematic review considers the strategies used to construct IPF experimental models, the detection indicators, TCM syndrome research, and evaluation systems, with the aim of providing a reference for IPF-related research.

Abstract:Chronic thromboembolic pulmonary hypertension ( CTEPH) is a severe form of pulmonary hypertension ( PH), and is classified as the fourth major category of pulmonary arterial hypertension. CTEPH is primarily caused by chronic thrombosis, leading to the obstruction of blood flow in the pulmonary arteries and result ing in a sustained increase in pulmonary artery pressure. The unclear pathogenesis of CTEPH, however, means that its early diagnosis is challenging, treatment options are limited, and prognosis assessment is often inaccurate. In-depth research into these mechanisms will thus improve our understanding of the pathophysiological processes of CTEPH,and also provide a theoretical basis for developing new therapeutic strategies. This review focuses on the current method of establishing CTEPH rat models and their advantages and disadvantages, offering researchers a reference for selecting and constructing CTEPH rat models.

Abstract:Inflammatory bowel disease ( IBD) is a non-specific chronic inflammatory bowel condition. Crohn’s disease(CD) and ulcerative colitis(UC) are the 2 main types of IBD. IBD is prone to recurrent attacks,which is associated with many factors, such as immune dysfunction, intestinal microenvironment homeostasis imbalance, and environmental and genetic factors; however, its specific pathogenesis is still unclear. Zebrafish has recently emerged as an emerging animal model and have been used extensively for mechanistic research into IBD,model construction, activity evaluation, and screening of anti-IBD agents, due to their unique biological advantages.Based on the latest research progress using zebrafish in the field of IBD, this review systematically introduces the intestinal development characteristics, tissue structure, intestinal immunity, IBD model, and the application of drug screening in zebrafish, to demonstrate the value of zebrafish in the study of IBD.

Abstract:Mitochondrial autophagy is an important mechanism for maintaining cellular homeostasis, closely related to the occurrence and development of cerebral ischemic injury, and is an important way of neuronal death. In recent years, a large number of experimental studies have confirmed that traditional Chinese medicine has a significant effect on treating cerebral ischemic injury. Its advantages of multi-target, multi pathway, low toxicity and high efficiency have become an important component of the treatment of cerebral ischemic injury. Traditional Chinese medicine formulas and monomeric active ingredients such as Xiaoxuming decoction, Zishen Huoxue formula,flavonoids, alkaloids, etc. can regulate mitochondrial autophagy related signaling pathways and targets, inhibit neuronal autophagic death, alleviate pathological damage to brain tissue, and exert neuroprotective effects. This article analyzes the molecular mechanism of traditional Chinese medicine regulating mitochondrial autophagy in the treatment of cerebral ischemic injury from four aspects: an overview of mitochondrial autophagy, related signaling pathways, its relationship with cerebral ischemic injury, and the regulatory effects of traditional Chinese medicine.The aim is to provide ideas and references for future basic research and clinical treatment.