ObjectiveTo investigate the therapeutic effects and mechanism of decoctions from four kinds of processed products of Aconiti Radix Lateralis Praeparata（ARLP） in deficiency-cold syndrome. MethodsA total of 36 SD rats were randomly divided into the control group， model group， Shengfupian（SFP） group， Paofuzi（PFZ） group， Heishunpian（HSP） group and Paofupian（PFP） group with 6 rats in each group. Except for the control group， rats in other groups were administered hydrocortisone sodium succinate via intramuscular injection to induce a cold deficiency syndrome model. After 14 consecutive days， each ARLP decoction pieces was administered via continuous gastric lavage at a dose of 12 g·kg^-1·d^-1 for 7 d， while the control and model groups received an equivalent volume of physiological saline. After the end of administration， body weight， spleen weight and thymus weight were measured for calculating the spleen and thymus indexes. Hematoxylin-eosin（HE） staining was used to observe the pathological morphology of adrenal tissue. The fully automatic biochemistry analyzer was used to measure the total cholesterol（TC）， triglyceride（TG）， lactic dehydrogenase（LDH） and lactate（LAC） levels in serum. Enzyme-linked immunosorbent assay（ELISA） was employed to measure the contents of 17-hydroxycorticosteroid（17-OHCS）， cortisol（CORT）， triiodothyronine（T₃）， thyroxine（T₄）， thyrotropin（TSH）， immunoglobulin（Ig） M， IgG， cyclic adenosine monophosphate（cAMP） and cyclic guanosine monophosphate（cGMP）. Western blot was used to measure the protein expression levels of protein kinase A（PKA）， cAMP response element-binding protein（CREB）， silent information regulator 1（Sirt1） and peroxisome proliferator-activated receptor γ coactivator-1α（PGC-1α）. And high performance liquid chromatography（HPLC） was used to determine the content of major alkaloids， followed by Pearson correlation analysis with pharmacodynamic indicators. ResultsAfter modeling， compare with the control group， the model rats exhibited symptoms such as lethargy and loose stools， mild abnormalities were observed in adrenal tissue structure， and both spleen and thymus indices were significantly reduced（P<0.01）. Thyroid， adrenal and immune system functions were suppressed， with decreased serum cAMP level and significantly elevated cGMP level（P<0.01）. Compared with the model group， the adrenal injury by hydrocortisone sodium succinate were repaired and the spleen index were increased significantly in all four ARLP groups（P<0.05， P<0.01）. The thymus index in SFP and PFZ groups were increased significantly（P<0.05）. The contents of T₃， TSH， 17-OHCS and CORT were increased significantly in SFP and PFZ groups（P<0.05）. In addition， the content of IgG in SFP， PFZ and PFP groups were increased significantly（P<0.01）， while the content of IgM in PFZ and HSP groups were also increased significantly（P<0.05）. Regarding the cyclic nucleotide system， PFZ significantly elevated cAMP level while reducing cGMP level（P<0.05）， exhibiting the most pronounced effect among the four decoction pieces. For energy metabolism indicators， PFZ significantly improved abnormal markers including TC， TG， LDH， and LAC（P<0.05）. HSP showed marked improvement effects on TG， LDH， and LAC（P<0.05）. Both PFZ and SFP significantly elevated the expression levels of PKA， CREB， Sirt1， and PGC-1α proteins（P<0.01）. Additionally， the diester alkaloids in ARLP showed a strong positive correlation with TG， IgG， and CORT， a strong negative correlation with LAC， a moderate positive correlation with T₄， and moderate negative correlations with cAMP and spleen index. Monomeric alkaloids showed strong positive correlations with TG and IgG， strong negative correlations with LAC， moderate positive correlations with CORT and T₄， and moderate negative correlations with cAMP and spleen index. However， the content of water-soluble alkaloids showed strong positive correlations with TC， LDH， 17-OHCS， T₃， TSH， and thymus index， moderate positive correlations with cAMP， CORT， T₄， and spleen index， and moderate negative correlation with cGMP. ConclusionAmong different processed ARLP decoction pieces， PFZ processed according to ZHANG Zhongjing's method exhibits the most potent warming and cold-dispelling effects. Its pharmacological actions are mediated through regulating the thyroid， adrenal， immune， cyclic nucleotide systems， and material-energy metabolism pathways. Among these， water-soluble alkaloids show strong or moderate correlations with more indicators of deficiency-cold syndrome and exhibit the highest content in PFZ. Therefore， PFZ processed according to ZHANG Zhongjing's method may exert its warming and cold-dispelling effects through water-soluble alkaloids.

ObjectiveTo explore the efficacy and mechanisms of Sini San in the treatment of depression and liver injury based on gut microbiota. MethodsThirty-two male Sprague-Dawley （SD） rats were randomly divided into a normal group， model group （M）， Sini San group （MS， 2.5 g·kg^-1）， and fluoxetine group （MF， 2 mg·kg^-1）. Except for the normal group， rats in the other three groups were subjected to chronic unpredictable mild stress （CUMS）. After 8 weeks， the open-field test and sucrose preference test were conducted. Enzyme-linked immunosorbent assay （ELISA） was used to detect serum corticosterone （CORT）， adrenocorticotropic hormone （ACTH）， corticotropin-releasing factor （CRF）， lipopolysaccharide （LPS）， Zonulin， interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， interleukin-1β （IL-1β）， γ-aminobutyric acid （GABA） levels in the hippocampus and prefrontal cortex， and brain-derived neurotrophic factor （BDNF） levels in the hippocampus. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect hippocampal BDNF mRNA expression. Serum alanine aminotransferase （ALT） and aspartate aminotransferase （AST） levels were measured using the ultraviolet lactate dehydrogenase method. The ultrastructure of the intestinal epithelium was observed by electron microscopy， and gut microbiota in rat feces were analyzed using 16S rDNA high-throughput sequencing. ResultsCompared with the normal group， the sucrose preference of rats in the model group was significantly reduced （P0.01）， whereas it was significantly increased in the Sini San group compared with the model group （P0.05）. Compared with the normal group， hippocampal GABA protein levels and BDNF mRNA expression in the model group were significantly decreased （P0.05）， and compared with the model group， both were significantly increased in the Sini San group （P0.05， P0.01）. Compared with the normal group， serum LPS and Zonulin levels in the model group were significantly increased （P0.05， P0.01）， and compared with the model group， Zonulin levels in the Sini San group were significantly decreased （P0.05）. No obvious changes were observed in the ultrastructure of the jejunal mucosa among groups. Compared with the normal group， widened and blurred tight junctions， sparse and shortened microvilli， and mitochondrial swelling with cristae disruption in epithelial cells were observed in the ileal and colonic mucosa of the model group， which were markedly improved in the Sini San and fluoxetine groups. The results of 16S rDNA high-throughput sequencing showed that Sini San improved CUMS-induced dysbiosis of Bacteroidetes and Proteobacteria. Correlation analysis indicated that Bacteroidetes and Proteobacteria were significantly correlated with depression-related indicators， liver function， and intestinal mucosal permeability. ConclusionSini San exerts antidepressant and hepatoprotective effects by improving Bacteroidetes and Proteobacteria and inhibiting the increase in intestinal mucosal permeability in CUMS rats.

ObjectiveTo explore the efficacy and mechanisms of Sini San in the treatment of depression and liver injury based on gut microbiota. MethodsThirty-two male Sprague-Dawley （SD） rats were randomly divided into a normal group， model group （M）， Sini San group （MS， 2.5 g·kg^-1）， and fluoxetine group （MF， 2 mg·kg^-1）. Except for the normal group， rats in the other three groups were subjected to chronic unpredictable mild stress （CUMS）. After 8 weeks， the open-field test and sucrose preference test were conducted. Enzyme-linked immunosorbent assay （ELISA） was used to detect serum corticosterone （CORT）， adrenocorticotropic hormone （ACTH）， corticotropin-releasing factor （CRF）， lipopolysaccharide （LPS）， Zonulin， interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）， interleukin-1β （IL-1β）， γ-aminobutyric acid （GABA） levels in the hippocampus and prefrontal cortex， and brain-derived neurotrophic factor （BDNF） levels in the hippocampus. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect hippocampal BDNF mRNA expression. Serum alanine aminotransferase （ALT） and aspartate aminotransferase （AST） levels were measured using the ultraviolet lactate dehydrogenase method. The ultrastructure of the intestinal epithelium was observed by electron microscopy， and gut microbiota in rat feces were analyzed using 16S rDNA high-throughput sequencing. ResultsCompared with the normal group， the sucrose preference of rats in the model group was significantly reduced （P<0.01）， whereas it was significantly increased in the Sini San group compared with the model group （P<0.05）. Compared with the normal group， hippocampal GABA protein levels and BDNF mRNA expression in the model group were significantly decreased （P<0.05）， and compared with the model group， both were significantly increased in the Sini San group （P<0.05， P<0.01）. Compared with the normal group， serum LPS and Zonulin levels in the model group were significantly increased （P<0.05， P<0.01）， and compared with the model group， Zonulin levels in the Sini San group were significantly decreased （P<0.05）. No obvious changes were observed in the ultrastructure of the jejunal mucosa among groups. Compared with the normal group， widened and blurred tight junctions， sparse and shortened microvilli， and mitochondrial swelling with cristae disruption in epithelial cells were observed in the ileal and colonic mucosa of the model group， which were markedly improved in the Sini San and fluoxetine groups. The results of 16S rDNA high-throughput sequencing showed that Sini San improved CUMS-induced dysbiosis of Bacteroidetes and Proteobacteria. Correlation analysis indicated that Bacteroidetes and Proteobacteria were significantly correlated with depression-related indicators， liver function， and intestinal mucosal permeability. ConclusionSini San exerts antidepressant and hepatoprotective effects by improving Bacteroidetes and Proteobacteria and inhibiting the increase in intestinal mucosal permeability in CUMS rats.

OBJECTIVE: To explore the genotype-phenotype correlation in a Chinese family with structural brain abnormalities due to variant of the TUBB gene. METHODS: A family undergoing prenatal diagnosis at Beijing Obstetrics and Gynecology Hospital in October 2024 was selected as the study subject. Clinical data were collected. Amniotic fluid sample was subjected to chromosomal copy number variation sequencing (CNV-seq). Trio whole-exome sequencing (Trio-WES) was carried out on the amniotic fluid and parental blood samples, and candidate variant was verified by Sanger sequencing. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: 2023-KY-076-01). RESULTS: Both prenatal ultrasound and fetal MRI showed deviation of brain midline, unilateral lateral ventriculomegaly, and bilateral gyral asymmetry. Trio-WES revealed that the fetus has harbored a maternally derived heterozygous missense variant of the TUBB gene [NM_178014.4: c.155A>G (p.N52S)]. Sanger sequencing confirmed that the woman and a previously terminated fetus both harbored the same variant. Both the proband and two fetuses exhibited similar neuroimaging abnormalities including midline deviation and asymmetrical gyri. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as likely pathogenic (PM2_Supporting+PS2_Moderate+PS3). CONCLUSION The heterozygous c.155A>G (p.N52S) variant was the TUBB gene probably underlay the pathogenesis of the structural brain abnormalities in this family. Above findings have expanded the phenotypic spectrum associated with the variant and facilitated the prenatal diagnosis for this family.
Humans ; Female ; Pregnancy ; Prenatal Diagnosis ; Tubulin/genetics* ; Adult ; Brain/diagnostic imaging* ; Male ; Pedigree ; DNA Copy Number Variations/genetics* ; Exome Sequencing ; Genetic Association Studies ; Magnetic Resonance Imaging

To improve the targeted therapeutic effect of magnolol (Mag) on neuroblastoma, Mag-loaded mitochondria-targeting immunoliposomes modified by datuximab (aGD2) and triphenylphosphine (TPP) (Mag/aGD2-T-ILN) were prepared, and their physicochemical properties, targeting characteristics and anti-tumor activity were evaluated. Physico-chemical properties showed that the surface of Mag/aGD2-T-ILN was smooth and spherical, with good dispersibility. The particle sizes, PDI and Zeta potentials of Mag/aGD2-T-ILN were measured to be (136.5 ± 5.1) nm, 0.184 ± 0.010 and (27.5 ± 3.6) mV, respectively. Mag/aGD2-T-ILN could release the drug continuously and slowly, and maintain good stability at 4 ℃. Cytotoxicity test exhibited that the IC50 of 2-ME/aGD2-T-ILN was (4.07 ± 0.48) µmol/L, and compared with free Mag, the toxicity of Mag/aGD2-T-ILN to SH-SY5Y cells increased by 6.4 times. Cellular binding and uptake assays suggested that Rho-aGD2-T-ILN could specifically target GD2-positive tumor cells and then further reach their mitochondria. Therapeutic efficacy indicated that Mag/aGD2-T-ILN could better suppress the growth of SH-SY5Y tumor cells in the body with lower toxicity and less side-effects. The results demonstrated that the Mag/aGD2-T-ILN nanoparticles system could achieve intracellular endocytosis through specific binding of antibodies and antigens between the carrier and the surface of tumor cells and electrostatic interaction, then effectively delivered and released the drugs into mitochondria by crossing the mitochondrial phospholipid membrane through TPP, and thus achieving mitochondria-targeting therapy of Mag/aGD2-T-ILN. Through the construction of this active targeting delivery system, the clinical application value of datuximab and Mag is improved, providing a novel approach for the clinical treatment of neuroblastoma.

Objective: To explore the nonlinear dynamic effects of social capital, adverse childhood experiences (ACEs) and depressive symptoms on suicidal behavior among vocational high school students, so as to provide theoretical basis and practical references for formulating suicide prevention strategies. Methods: A convenience sampling method was employed to include 668 students from a vocational high school from Wuhan in March 2023. Social capital was used as the asymmetry variable, while ACEs and depressive symptoms were used as bifurcation variables, a cusp catastrophe model was constructed to analyze the nonlinear changes in suicidal behavior among vocational high school students, and its fit was compared with linear and Logistic regression models. Results: Among students in the health vocational high school in Wuhan, only suicidal ideation accounted for 8.5%, only suicide attempt for 18.6%, neither accounted for 31.9%, and both for 41.0%. Gender, left behind experience, family economic status, parental parenting styles, depressive symptoms, social capital, and ACEs were all related factors influencing suicidal behavior among vocational high school students ( χ 2/H=19.03, 13.33, 21.11, 46.70, 144.38, 24.61, 118.77, all P <0.05). Violin plots showed a bimodal distribution of suicidal behavior, indicating nonlinear variation characteristics. The cusp catastrophe model results showed that social capital was negatively correlated with suicidal behavior, but the relationship was bifurcated by ACEs ( α social capital = -0.006 , β ACEs =0.075) and depressive symptoms ( α social capital =-0.013, β depressive =0.028) (all P <0.05). When both ACEs and depressive symptoms coexisted, the impact of ACEs was stronger ( β ACEs =0.077, β depressive =0.014) (both P <0.05). The cusp catastrophe model fitted ( R 2=0.886, 0.881, 0.882) better than the linear ( R 2=0.258, 0.219, 0.258) and Logistic regression models ( R 2= 0.242, 0.211 , 0.176). Gender stratified analysis results showed that bifurcation effect of ACEs was stronger in males than in females( β boys =0.224, β girls =0.086); in females, both ACEs and depressive symptoms had a bifurcation effect, with the former showing a stronger effect ( β ACEs =0.062, β depressive =0.015) (all P <0.05). Conclusions Suicidal behavior among vocational high school students exhibits nonlinear characteristics. Improving social capital to reducing ACEs and depressive symptoms may contribute to decreasing adolescent suicidal behaviors.

Background Pyrethroid pesticides (PYRs) can cross the placental barrier to cause intrauterine fetal exposure, which may lead to developmental immunotoxicity (DIT). However, the specific effect of maternal PYR exposure during pregnancy on the cellular immune function of 1-year-old children remains unclear. Objective To explore the effect of PYRs exposure throughout the entire pregnancy on peripheral blood lymphocytes in 1-year-old children and potential sensitive window period of PYRs exposure. Methods A birth cohort was established by enrolling pregnant women in their first trimester and following them and their infants until one year of age. Ultra-high performance liquid chromatography-tandem mass spectrometry was used to detect the levels of PYRs metabolites, including 3-phenoxybenzoic acid (3PBA), 4-fluoro-3-phenoxybenzoic acid (4F3PBA), and cis-3-(2,2-dichlorovinyl)-2,2- dimethylcyclopropane carboxylic acid (cis-DBCA), in the urine of pregnant women during the first trimester (gestational weeks 6-12), the second trimester (gestational weeks 21-24), and the third trimester (gestational weeks 33-36). Peripheral blood leukocyte and lymphocyte counts were measured in children at 12 months of age using the Coulter principle combined with flow cytometry. Exposure levels of PYRs metabolites in each trimester were divided into low, moderate, and high exposure groups based on the 25th (P₂₅) and 75th (P₇₅) percentiles. Meanwhile, participants were classified as having repeated high or low exposure if their metabolite levels were > P₇₅ or <P₂₅ in at least two trimesters, respectively, while all others were categorized as having repeated moderate exposure. Generalized linear models were used to analyze the associations between trimester-specific and repeated PYRs metabolite exposure levels and the peripheral blood white blood cell (WBC) and lymphocyte counts in children aged 1 year. Results A total of 336 mother-child pairs were included in this study. For the pregnant women, the total detection rates of maternal urinary 3PBA, 4F3PBA, and cis-DBCA across the three trimesters of pregnancy were 80.5%, 100.0%, and 81.3%, respectively; and median creatinine-corrected concentrations were 0.24, 0.36, and 0.42 μg·g⁻¹, respectively. In children aged 1 year, the mean WBC and lymphocyte counts in peripheral blood were (8.9±2.0)×10⁹·L⁻¹ and (5.7±1.6)×10⁹·L⁻¹, respectively. The results of the generalized linear model analysis indicated that compared to the low exposure group, the high cis-DBCA exposure group during the third trimester of pregnancy had significantly lower peripheral blood WBC count (β=−0.87, 95%CI: −1.51, −0.23) and lymphocyte count (β=−0.64, 95%CI: −1.15, −0.13); and the repeated high-exposure group of cis-DBCA had significantly lower peripheral blood WBC count (β=−1.34, 95%CI: −2.34, −0.34) and lymphocyte count (β=−0.80, 95%CI: −1.60, −0.01) than the repeated low exposure group. Similarly, the repeated moderate-exposure group of cis-DBCA had a significantly lower peripheral blood WBC count (β=−0.83, 95%CI: −1.59, −0.07) than the repeated low exposure group. Conclusion High maternal exposure to PYRs with cis-DBCA as the major metabolite exposure is associated with decreased peripheral leukocyte and lymphocyte counts in children aged 1 year, and repeated high-level exposure throughout gestation appears to exacerbate DIT in offspring. The third trimester of pregnancy maybe a sensitive window for children's DIT induced by exposure to PYRs during pregnancy.

Colorectal cancer (CRC) is the third most commonly diagnosed malignancy and the second leading cause of cancer-related mortality worldwide. Despite therapeutic advancements over recent decades, the prognosis for patients with metastatic CRC (mCRC) remains poor. Approximately 2%-4% of mCRC cases exhibit human epidermal growth factor receptor 2 (HER2) amplification or overexpression, defining a distinct molecular subtype. This HER2-positive status is strongly associated with primary resistance to anti-epidermal growth factor receptor (EGFR) therapies, which are the standard of care for patients with RAS wild-type tumors. Beyond its well-established role in breast and gastric cancers, HER2 has emerged as a pivotal biomarker and actionable therapeutic target in mCRC. However, selecting appropriate treatment strategies remains challenging due to patient heterogeneity and diverse molecular subtypes. This review systematically summarizes the molecular biology, diagnostic strategies, and advances in targeted therapies for HER2-positive mCRC. On the diagnostic front, we discuss the applications of immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), next-generation sequencing (NGS), and circulating tumor DNA (ctDNA) detection technologies. We highlight discrepancies in diagnostic criteria across key clinical trials—such as HERACLES, DESTINY, and MOUNTAINEER—underscoring the urgent need for standardized, CRC-specific definitions to ensure consistent patient selection and comparability of efficacy data across studies. Although NGS enables comprehensive genomic profiling, its cost-effectiveness relative to traditional methods must be carefully considered. Therapeutically, we summarize clinical trial data for HER2-directed agents, including tyrosine kinase inhibitors (TKIs) such as tucatinib and lapatinib, monoclonal antibodies like trastuzumab, bispecific antibodies, and antibody-drug conjugates (ADCs) such as trastuzumab deruxtecan. We review dual-targeting strategies and note recent FDA approvals that represent significant milestones in second-line treatment. Additionally, we explore the potential of combining immune checkpoint inhibitors with HER2-targeted therapies to enhance antitumor immunity through mechanisms including antibody-dependent cellular cytotoxicity (ADCC) and modulation of the tumor microenvironment. ADCs enable precise delivery of cytotoxic payloads, reducing off-target toxicity while effectively inhibiting oncogenic pathways. A substantial portion of this review is dedicated to dissecting the molecular mechanisms underlying primary and acquired resistance to HER2-targeted therapies—persistent challenges that limit clinical benefit. These mechanisms include reactivation of downstream signaling pathways such as PI3K/AKT/mTOR and MAPK, concurrent mutations in genes like KRAS or BRAF, and alterations in HER2 expression that compromise treatment efficacy. For instance, specific HER2 mutations (e.g., L755S) can reduce drug binding affinity, while ctDNA monitoring facilitates early detection of emerging resistance clones during disease progression, thereby enabling timely therapeutic adjustments. Tumor heterogeneity and dynamic interactions with the microenvironment further complicate resistance patterns observed in clinical practice. HER2-targeted therapy represents a new frontier in precision oncology for mCRC, offering renewed hope for improving patient outcomes. Realizing this potential will require continued optimization of diagnostic algorithms and treatment workflows. Future efforts must focus on overcoming resistance, validating liquid biopsy approaches for dynamic monitoring, and establishing unified clinical guidelines. HER2 has become an essential biomarker for stratifying mCRC patients beyond traditional RAS and BRAF status, underscoring the shift from empiric treatment to biomarker-driven precision medicine. International, multidisciplinary collaboration will be critical to validate emerging biomarkers and refine treatment algorithms globally.

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.

BACKGROUND:Bone tissue loss caused by tumors and trauma can have an adverse effect on postoperative rehabilitation.Therefore,scaffold materials are usually implanted during treatment.However,the existing implant materials are relatively simple and lack antibacterial properties.Early implantation may lead to iatrogenic autoinfection and have an adverse effect on osteogenesis.OBJECTIVE:To construct a KR-12-a5 polypeptide-nanohydroxyapatite-small intestinal submucosa composite scaffold and evaluate its feasibility as a material for promoting bone defect repair.METHODS:The small intestinal submucosa scaffold and the small intestinal submucosa scaffold containing 25,50,and 100 mg/mL nanohydroxyapatite(referred to as nHA-SIS scaffold)were prepared by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride/N-hydroxysuccinimide cross-linking method.The appropriate scaffold was screened for subsequent experiments by mechanical property testing.The antibacterial properties of KR-12-a5 polypeptide solution against Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum were detected.The nHA-SIS scaffolds were immersed in 250,500,and 1 000 μg/mL KR-12-a5 peptide solutions for 24 hours,and then freeze-dried to obtain peptide-loaded nanohydroxyapatite-porcine small intestinal submucosa composite scaffolds(denoted as P-nHA-SIS scaffolds).The sustained-release properties of the three groups of scaffolds were characterized.The nHA-SIS scaffolds and the three groups of P-nHA-SIS scaffolds were co-cultured with Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum for 24 hours or 48 hours.The scaffolds with strong antibacterial ability were screened by live and dead bacteria staining and scanning electron microscopy for subsequent experiments.The degradation properties and water absorption rates of the uncross-linked small intestinal submucosa scaffolds,cross-linked small intestinal submucosa scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were characterized.The extracts of cross-linked small intestinal submucosal scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were co-cultured with MC3T3-E1 cells.CCK-8 assay and live-dead cell staining were performed.The effects of the extracts of the three scaffolds on the migration of MC3T3-E1 cells were detected by Transwell chamber assay.RESULTS AND CONCLUSION:(1)The elastic modulus and compressive strength of 25,50,and 100 mg/mL nHA-SIS scaffolds were higher than those of small intestinal submucosal scaffolds(P＜0.05),among which the elastic modulus and compressive strength of 25 mg/mL nHA-SIS scaffolds were the highest,and this group of scaffolds were selected for subsequent experiments to load peptides.(2)KR-12-a5 peptide had strong antibacterial activity against common bacteria in bone defects(Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum).The three groups of P-nHA-SIS scaffolds all had sustained release properties.With the increase of peptide mass concentration,the antibacterial property of P-nHA-SIS scaffold was enhanced.Among them,the P-nHA-SIS scaffold loaded with 500 μg/mL peptide had achieved a satisfactory antibacterial effect,and this group of scaffolds would be selected in the future.(3)The degradation rate of the three groups of cross-linked scaffolds was lower than that of the uncross-linked scaffolds,and the water absorption rate was greater than that of the uncross-linked scaffolds.P-nHA-SIS scaffolds could promote the proliferation and migration of MC3T3-E1 cells without affecting the activity of MC3T3-E1 cells.(4)The results show that P-nHA-SIS scaffolds have strong antibacterial properties and the ability to promote the proliferation and migration of MC3T3-E1 cells,and are expected to be used in bone defect repair.