Objective To investigate the distribution characteristics of pathogens causing infections within 90 days after liver transplantation and the influencing factors of infection. Methods Clinical data of 176 recipients who underwent liver transplantation at the Liver Transplant Center of Beijing Friendship Hospital Affiliated to Capital Medical University from September 2021 to August 2024 were retrospectively analyzed. Patients were divided into the infection group (n=124) and the non-infection group (n=52) based on whether they developed infection within 90 days after transplantation. The distribution characteristics of pathogens in infected patients were analyzed. Univariate and multivariate logistic regression analyses were used to explore the influencing factors of infection. Results Among the 176 liver transplant recipients, 124 cases developed 243 episodes of 518 bacterial, fungal, viral or mycoplasma infections within 90 days after transplantation, with an overall infection rate of 70.5% (124/176). The composition of pathogens was mainly Gram-negative bacteria (38.6%, 200/518), followed by Gram-positive bacteria (32.2%, 167/518) and viruses (15.4%, 80/518), and fungi accounted for 13.1% (68/518). Among Gram-negative bacteria, the main pathogen was Klebsiella pneumoniae (6.8%, 35/518), and among Gram-positive bacteria, the main pathogen was Enterococcus faecalis (8.5%, 44/518). Viruses included Epstein-Barr virus (3.7%, 19/518) and cytomegalovirus (3.7%, 19/518), and fungi were mainly Candida albicans (6.8%, 35/518). The most common infection site among the 243 episodes was pulmonary infection (42.0%, 102/243), followed by abdominal infection (22.6%, 55/243) and bloodstream infection (18.1%, 44/243). The infections mainly occurred within 2 weeks after transplantation (60.9%, 148/243). Multivariate logistic regression analysis indicated that preoperative infection within 2 weeks, a high preoperative model for end-stage liver disease (MELD) score, and preoperative sarcopenia were independent risk factors for infection within 90 days after liver transplantation (all odds ratio>1, P<0.05). After multivariate correction, the levels of CD4⁺T cells and CD8⁺T cells within 90 days after surgery were independently associated with the occurrence of infection. Low levels of CD4⁺T cells and CD8⁺T cells might be related to an increased risk of infection. Conclusions The infection rate after liver transplantation is high, and the pathogens are mainly Gram-negative bacteria. The lungs are the most common infection site. Preoperative MELD score, preoperative sarcopenia and preoperative infection within 2 weeks are independent risk factors for infection within 90 days after liver transplantation. Regular monitoring of immune indicators CD4⁺T cells and CD8⁺T cells levels after transplantation is helpful to reduce the occurrence of post-transplantation infection.

Osteoarthritis (OA), a highly prevalent degenerative joint disease worldwide, is defined by articular cartilage degradation, abnormal bone remodeling, and persistent chronic inflammation. It severely compromises patients’ quality of life, and currently, there is no radical cure. Abnormal mechanical stress is widely regarded as a core driver of OA pathogenesis, and the exploration of mechanical signal perception and transduction mechanisms has become crucial for deciphering OA’s pathophysiological processes. Piezo1, a key mechanosensitive cation channel belonging to the Piezo protein family, has recently gained significant attention due to its pivotal role in mediating cellular responses to mechanical stimuli in joint tissues. This review systematically examines Piezo1’s expression patterns, regulatory mechanisms, and pathological functions in OA, with a particular focus on its dual roles in modulating chondrocyte homeostasis and bone metabolism disorders, while also delving into the underlying molecular signaling pathways and potential therapeutic implications. Piezo1, consisting of approximately 2 500 amino acids and forming a unique trimeric propeller-like structure, is widely expressed in chondrocytes, osteocytes, mesenchymal stem cells, and synovial cells. It exhibits permeability to cations such as Ca²⁺, K⁺, and Na⁺, and directly responds to membrane tension changes induced by mechanical stimuli like fluid shear stress and mechanical overload. In OA patients and animal models, Piezo1 expression is significantly upregulated, especially in cartilage regions subjected to abnormal mechanical stress (e.g., human temporomandibular joint cartilage). This overexpression is closely associated with aggravated cartilage degeneration, increased chondrocyte apoptosis, accelerated cellular senescence, and intensified inflammatory responses. Mechanical overload and pro-inflammatory cytokines (e.g., IL-1β) are key inducers of Piezo1 upregulation: IL-1β activates the PI3K/AKT/mTOR signaling pathway to enhance Piezo1 expression, forming a pathogenic positive feedback loop that inhibits chondrocyte autophagy, promotes apoptosis, and further accelerates joint degeneration. Mechanistically, Piezo1 mediates OA progression through multiple interconnected pathways. When activated by mechanical stress, Piezo1 triggers excessive Ca²⁺ influx, leading to endoplasmic reticulum stress (ERS) and mitochondrial dysfunction, which directly induce chondrocyte apoptosis. This process involves the activation of downstream signaling cascades such as cGAS-STING and YAP-MMP13/ADAMTS5. YAP, a transcriptional regulator, upregulates the expression of matrix metalloproteinase 13 (MMP13) and aggrecanase (ADAMTS5), thereby accelerating cartilage matrix degradation. Additionally, Piezo1-driven Ca²⁺ overload promotes the accumulation of reactive oxygen species (ROS) and upregulates senescence markers (p16 and p21), accelerating chondrocyte senescence via the p38MAPK and NF-κB pathways. Senescent chondrocytes secrete senescence-associated secretory phenotype (SASP) factors (e.g., IL-6, IL-1β), further amplifying joint inflammation. In terms of bone metabolism, Piezo1 maintains joint homeostasis by promoting the differentiation of fibrocartilage stem cells into chondrocytes and balancing bone formation and resorption through regulating the FoxC1/YAP axis and RANKL/OPG ratio. Therapeutically, targeting Piezo1 shows promising potential. Preclinical studies have demonstrated that Piezo1 inhibitors (e.g., GsMTx4) can reduce joint damage and alleviate pain in OA mice. Simultaneously, siRNA-mediated co-silencing of Piezo1 and TRPV4 (another mechanosensitive channel) decreases intracellular Ca²⁺ concentration, inhibits chondrocyte apoptosis, and promotes cartilage repair. Conditional knockout of Piezo1 using Gdf5-Cre transgenic mice alleviates cartilage degeneration in post-traumatic OA models by downregulating MMP13 and ADAMTS5 expression. Despite existing challenges, such as off-target effects of inhibitors, inefficient local drug delivery, and interindividual genetic variability, strategies like developing selective Piezo1 antagonists, optimizing targeted nanocarriers, and combining Piezo1-targeted therapy with physical therapy provide viable avenues for clinical translation. The authors propose that Piezo1 serves as a critical therapeutic target for OA, and future research should focus on deciphering its context-dependent regulatory networks, developing tissue-specific intervention strategies, and validating their efficacy and safety in clinical trials to address the unmet medical needs of OA patients.

Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe²⁺), whereas clMagR favors ferric iron (Fe³⁺) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe²⁺-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe²⁺/Fe³⁺ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.

Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe²⁺), whereas clMagR favors ferric iron (Fe³⁺) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe²⁺-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe²⁺/Fe³⁺ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.

Objective To investigate the predictive value of preoperative combined detection of neutrophil-to-lymphocyte ratio (NLR) and prothrombin time-international normalized ratio to albumin ratio (PTAR) for early abdominal infection after liver transplantation. Methods Clinical data of 287 recipients who underwent liver transplantation at the Liver Transplant Center of Beijing Friendship Hospital, Affiliated to Capital Medical University, from January 2020 to April 2024 were retrospectively analyzed. The patients were divided into infection group (n=60) and non-infection group (n=227) based on whether abdominal infection occurred within 30 days after surgery. The distribution characteristics of pathogens and infection time in infected patients were analyzed. Spearman correlation analysis was used to assess the correlation between NLR, PTAR, Child-Pugh score and preoperative model for end-stage liver disease (MELD) score. Univariate and multivariate logistic regression analyses were performed to identify risk factors for abdominal infection. Receiver operating characteristic (ROC) curves were plotted for NLR, PTAR, and the combined prediction model to evaluate their predictive efficacy for abdominal infection after liver transplantation. Based on the cutoff value of the combined model, recipients were divided into low-risk and high-risk groups, and Kaplan-Meier analysis was used to compare the cumulative incidence of abdominal infection within 30 days after surgery between the two groups. Results Among the 287 recipients who underwent liver transplantation, 60 developed bacterial or fungal abdominal infections postoperatively. A total of 86 strains were isolated from infected patients, with Gram-negative bacteria accounting for 58%, Gram-positive bacteria for 36%, and fungi for 5%. Preoperative NLR and PTAR were positively correlated with Child-Pugh and MELD scores (all 1 > r > 0, P < 0.05). Logistic regression analysis showed that preoperative NLR, preoperative PTAR, postoperative ICU stay duration and postoperative biliary leakage were risk factors for abdominal infection within 30 days after surgery. The area under the curve (AUC) for NLR, PTAR, Child-Pugh score and MELD score were 0.771, 0.735, 0.650 and 0.741, respectively. The AUC for the combined NLR and PTAR prediction model was 0.824 (95% confidence interval: 0.763-0.885, P < 0.001), with a cutoff value of 0.168. Kaplan-Meier analysis showed that the cumulative incidence of abdominal infection within 30 days after surgery was lower in the low-risk group than in the high-risk group, with statistically significant difference (P < 0.001). Conclusions Preoperative NLR and PTAR are independent risk factors for abdominal infection within 30 days after liver transplantation. The combined prediction model of NLR and PTAR may effectively identify high-risk recipients for early abdominal infection after liver transplantation, providing basis for early intervention.

Objective:To explore the effects and mechanisms of Shen-su-yin (SSY) on acute lung injury (ALI) in rats based on untargeted Metabolomics, network pharmacology, and experimental verification.Methods:Untargeted Metabolomics was performed to detect the ingredients of SSY by using ultra-high performance liquid chromatography-Q-exactive orbitrap mass spectrum, and the active ingredients were screened from the detected ingredients. Common targets of the active ingredient targets and ALI targets were utilized to screen hub targets to perform gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis. Then, key hub targets were selected from the hub targets, and the active ingredients-hub targets network was built to screen core ingredients. Subsequently, molecular docking was performed between the key hub targets and the core ingredients. 48 rats were randomly and equally divided into 4 groups by using a random number table: normal control group, lipopolysaccharide-induced ALI group, ALI+SSY group, and ALI+dexamethasone group. 24 hours after lipopolysaccharide induction, the levels of respiratory rate, blood lactate, lung wet/dry weight ratio, ALI score, inflammatory factors of bronchoalveolar lavage fluid, and oxidative stress mediators of lung tissue in each group were evaluated, and the expression of phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT)-glycogen synthase kinase (GSK) 3β-nuclear factor erythroid 2-related factor 2 (Nrf2)/nuclear factor (NF)-κB signaling pathway was also detected by using Western blot. Finally, one-way analysis of variance, Welch test, or Kruskal-Wallis H test was used to compare data differences among groups. Results:A total of 415 ingredients were detected from the SSY. 66 of the detected ingredients were identified as active ingredients, and 10 of them were selected as core ingredients. The number of common targets, hub targets, and key hub targets was 337, 50, and 10, respectively. Total of 285 biological processes, 32 cellular components, and 51 molecular functions were enriched though GO analysis, and 148 cell signaling pathways such as pathways in cancer and PI3K-AKT signaling pathway were enriched though KEGG analysis. Molecular docking studies revealed that all binding energies between the 10 key hub targets and the 10 core ingredients were less than -5 kcal/mol. Compared with the ALI group, the levels of the respiratory rate, blood lactate, and lung wet/dry weight ratio in ALI+SSY group were significantly decreased (all P<0.01), and the level of ALI score showed a downward trend, but the difference was not statistically significant ( P>0.05). In addition, the levels of interleukin-6, interleukin-1β, and tumor necrosis factor-α in bronchoalveolar lavage fluid and the levels of malondialdehyde, protein carbonyl, and 8-hydroxy-2-deoxyguanosine in lung tissue of rats in ALI+SSY group were significantly decreased in comparison with those in ALI group (all P<0.01). Moreover, compared with the ALI group, the phosphorylation levels of PI3K p85α, AKT1, and GSK3β and the expression level of Nrf2 in lung tissue of ALI+SSY group were significantly up-regulated (PI3K p85α phosphorylation and AKT1 phosphorylation, P<0.01; GSK3β phosphorylation and Nrf2, P<0.05), while the phosphorylation level of NF-κB p65 was significantly down-regulated ( P<0.01). Conclusions:Active ingredients detected from SSY via untargeted Metabolomics can inhibit oxidative stress and inflammation in ALI rats by regulating the PI3K-AKT-GSK3β-Nrf2/NF-κB signaling pathway, thereby alleviating lung lesions.

For middle-aged and elderly patients with conditions such as spinal fractures and degenerative spinal diseases, spinal internal fixation is a core surgical procedure for reconstructing spinal stability, heavily relying on the biomechanical stability provided by pedicle screw systems. Whereas, these patients are often complicated by osteoporosis that can significantly compromise the stability of the bone-pedicle screw interface, leading to a marked increase in pedicle screw loosening and surgical failure rates. The bone cement-augmented pedicle screw technique, which involves injecting bone cement into the vertebral body or screw trajectory to optimize the mechanical properties of the bone-pedicle screw composite, has been proven to significantly enhance fixation strength and effectively prevent screw-related failures, thereby reducing the incidence of internal fixation failure in high-risk populations undergoing spinal fusion. However, the widespread clinical application of this technique has faced challenges such as inaccurate clinical decision-making (indication and contraindication selection), non-standardized operative practices, and insufficient awareness of complication prevention, resulting in considerable variability in clinical outcomes and even severe complications. To address this, Prof. Luo Fei from First Affiliated Hospital of Army Medical University initiated the project and the Chinese Association Orthopaedic Surgeons organized relevant experts to develop the Evidence-based clinical practice guideline for bone cement-augmented pedicle screw technique ( version 2025), based on current evidence. The guidelines put forward 8 recommendations regarding the clinical value, scope of application, and operational standards of the technique, aiming to provide evidence-based medical support and technical standardization for clinical decision-making.

Objective:To develop a treatment-related quality of life scale for Chinese patients with multiple myeloma (MM) and to test its reliability and validity.Methods:The initial scale was constructed through a literature search, Delphi expert correspondence, and cognitive testing. This study conducted a preliminary survey of 379 patients with MM and a formal survey of 865 patients from the hematology departments of 155 hospitals nationwide from February 2024 to March 2024. The final scale was obtained after conducting item analysis and reliability and validity tests on the initial scale.Results:The constructed scale contains 36 items covering six domains: physiological, psychological, social, treatment side effects, general health, and others. In the preliminary survey, the Cronbach’s alpha coefficient of each item ranged from 0.597 to 0.939, and the test-retest reliability was 0.747 ( P<0.001). Exploratory factor analysis extracted eight common factors with a cumulative variance contribution of 60.058%. In the formal survey, the Cronbach’s alpha coefficient of each item ranged from 0.484 to 0.930, and the test-retest reliability was 0.835 ( P<0.001). Confirmatory factor analysis revealed a comparative fit index of 0.750, a root-mean-square error of approximation of 0.090, and a root-mean-square residual of 0.067. Conclusion:The treatment-related quality of life scale for Chinese patients with MM designed in this study exhibited good reliability and validity, reflecting the impact of treatment on the quality of life of patients. This scale can provide a reference to clinicians for assessing the disease status of patients.

OBJECTIVE: To evaluate the dynamic changes of glucocorticoid (GC) dose and the feasibility of GC discontinuation in rheumatoid arthritis (RA) patients under the background of Chinese medicine (CM). METHODS: This multicenter retrospective cohort study included 1,196 RA patients enrolled in the China Rheumatoid Arthritis Registry of Patients with Chinese Medicine (CERTAIN) from September 1, 2019 to December 4, 2023, who initiated GC therapy. Participants were divided into the Western medicine (WM) and integrative medicine (IM, combination of CM and WM) groups based on medication regimen. Follow-up was performed at least every 3 months to assess dynamic changes in GC dose. Changes in GC dose were analyzed by generalized estimator equation, the probability of GC discontinuation was assessed using Kaplan-Meier curve, and predictors of GC discontinuation were analyzed by Cox regression. Patients with <12 months of follow-up were excluded for the sensitivity analysis. RESULTS: Among 1,196 patients (85.4% female; median age 56.4 years), 880 (73.6%) received IM. Over a median 12-month follow-up, 34.3% (410 cases) discontinued GC, with significantly higher rates in the IM group (40.8% vs. 16.1% in WM; P<0.05). GC dose declined progressively, with IM patients demonstrating faster reductions (median 3.75 mg vs. 5.00 mg in WM at 12 months; P<0.05). Multivariate Cox analysis identified age <60 years [P<0.001, hazard ratios (HR)=2.142, 95% confidence interval (CI): 1.523-3.012], IM therapy (P=0.001, HR=2.175, 95% CI: 1.369-3.456), baseline GC dose ⩽7.5 mg (P=0.003, HR=1.637, 95% CI: 1.177-2.275), and absence of non-steroidal anti-inflammatory drugs use (P=0.001, HR=2.546, 95% CI: 1.432-4.527) as significant predictors of GC discontinuation. Sensitivity analysis (545 cases) confirmed these findings. CONCLUSIONS RA patients receiving CM face difficulties in following guideline-recommended GC discontinuation protocols. IM can promote GC discontinuation and is a promising strategy to reduce GC dependency in RA management. (Trial registration: ClinicalTrials.gov, No. NCT05219214).
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Arthritis, Rheumatoid/drug therapy* ; Glucocorticoids/therapeutic use* ; Medicine, Chinese Traditional ; Retrospective Studies

This study aimed to investigate the underlying mechanisms of Duhuo Jisheng Decoction(DJD) in the prevention and treatment of knee osteoarthritis(KOA). Forty SPF New Zealand rabbits were randomly divided using SPSS 26.0 software into five groups: blank group, model group, low-dose DJD group, high-dose DJD group, and high-dose DJD+phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR) signaling pathway activator group(high-dose DJD+740Y-P group), with eight rabbits in each group. Except for the blank group, the KOA model was established in the other groups using papain injection into the knee joint cavity combined with forced flexion of the knee joint. The day after modeling, the blank group and model group were given normal saline at 10 mL·kg~(-1) by gavage, the low-dose DJD group received DJD at 8.8 g·kg~(-1) by gavage, the high-dose DJD group received DJD at 35.2 g·kg~(-1) by gavage, and the high-dose DJD+740Y-P group received DJD at 35.2 g·kg~(-1) by gavage along with 740Y-P at 0.15 μmoL·kg~(-1) injected via the auricular vein. All groups received treatment continuously for four weeks. After modeling and intervention, behavioral observations were performed for all groups, and after the intervention, imaging assessments of the knee joints were conducted. Cartilage from the knee joints was collected, and gross morphological changes were observed. Pathological changes in cartilage tissue were examined using hematoxylin-eosin(HE) staining. The results of these observations were quantitatively evaluated using the Lequesne MG score, Kellgren-Lawrence(K-L) grading, Pelletier score, and Mankin score. ELISA was used to measure the levels of interleukin-1β(IL-1β), interleukin-18(IL-18), and matrix metalloproteinase 13(MMP13) in cartilage tissue. Real-time RT-PCR was used to detect the mRNA expression levels of PI3K, Akt, mTOR, Nod-like receptor protein 3(NLRP3), cysteine protease 1(caspase-1), and gasdermin D(GSDMD) in cartilage tissue. Western blot was employed to measure the protein expression levels of PI3K, Akt, mTOR, NLRP3, caspase-1, and GSDMD. The results showed that compared with the blank group, the model group exhibited significant knee joint degeneration, increased Lequesne MG score, K-L grading, Pelletier score, and Mankin score, elevated levels of IL-1β, IL-18, and MMP13 in cartilage tissue, activation of PI3K, Akt, and mTOR phosphorylation along with increased mRNA expression levels, and elevated protein and mRNA expression levels of NLRP3, caspase-1, and GSDMD. Compared with the model group, these indicators were reversed in both the low-dose and high-dose DJD groups, with the high-dose group showing greater decline degree than the low-dose DJD group. However, compared with the high-dose DJD group, the improvements in knee joint degeneration were less pronounced in the high-dose DJD+740Y-P group, with increased Lequesne MG score, K-L grading, Pelletier score, Mankin score, elevated levels of IL-1β, IL-18, and MMP13, activation of PI3K, Akt, and mTOR phosphorylation along with increased mRNA expression, and increased protein and mRNA expression levels of NLRP3, caspase-1, and GSDMD. In conclusion, DJD is effective and safe in the treatment of KOA, and its mechanism may be related to the inhibition of PI3K/Akt/mTOR signaling pathway-mediated pyroptosis in cartilage tissue, thereby improving knee joint bone structure, reducing the inflammatory response, and preventing cartilage matrix degradation.
Animals ; Drugs, Chinese Herbal/administration & dosage* ; Rabbits ; TOR Serine-Threonine Kinases/genetics* ; Osteoarthritis, Knee/genetics* ; Proto-Oncogene Proteins c-akt/genetics* ; Signal Transduction/drug effects* ; Male ; Disease Models, Animal ; Pyroptosis/drug effects* ; Phosphatidylinositol 3-Kinases/genetics* ; Humans ; Female