The auxin/indole-3-acetic acid (Aux/IAA) gene family is an important regulator for plant growth hormone signaling, involved in plant growth, development, as well as response to environmental stresses. In the present study, we identified SmIAA7 which is potentially associated with Salvia miltiorrhiza leaf development through comparatively analyzed the transcriptome data from different pinnate leaves. SmIAA7 was successfully isolated from S. miltiorrhiza using the specific primers. Then subsequent bioinformatic analysis, prokaryotic expression and purification, subcellular localization, and induction expression analysis under auxin and abiotic stress were performed. The full-length of SmIAA7 contained an ORF of 684 bp encoding a protein of 227 amino acid with a molecular weight of 25.3 kD. Conserved domain analysis showed that SmIAA7 contains the conserved Aux_IAA domain (pfam02309). Sequence analysis and phylogenetic tree analysis results indicated SmIAA7 was phylogenetically close to IAA7 and IAA14 from other plants, suggesting SmIAA7 involved in plant growth and development as well as response to environmental stresses. The prokaryotic expression vector pET28a-SmIAA7 was constructed and SmIAA7 recombinant protein was successfully expressed in E. coli Rosetta (DE3) strain. Subcellular localization experiment demonstrated that SmIAA7 localized in the nucleus of plant cells. Real-time fluorescence quantitative PCR results showed that the expression level of SmIAA7 was upregulated in response to auxin. Drought, low temperature, and salt stress significantly increased the transcript level of SmIAA7 gene. This study lays a foundation for further elucidating the role of SmIAA7 in leaf development, signal transduction, and stress defense in S. miltiorrhiza.

ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.

ObjectiveTo investigate the effects of different fermentation methods and times on the fungal flora and chemical composition of Aurantii Fructus， in order to obtain the optimal fermentation conditions and flora structure， and to ensure the stability and controllability of the fermented varieties. MethodsScanning electron microscopy was used to observe and analyze the colony characteristics on the surface of Aurantii Fructus under different fermentation conditions. Internal transcribed spacer 2（ITS2） high-throughput sequencing， combined with fungal community diversity analysis and fungal community structure analysis， were used to obtain the fungal flora microbial categories of Aurantii Fructus under the conditions of traditional pressure-shelf fermentation and non-pressure-shelf natural fermentation for 7， 14， 21 d（numbered Y1-Y3 for the former， and numbered F1-F3 for the latter）， respectively. At the same time， the chemical components in the fermentation process were detected by ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry（UPLC-Q-TOF-MS/MS）， combined with principal component analysis（PCA）， partial least squares-discriminant analysis（PLS-DA） and compound retention time， parent ions， characteristic fragment ions and other information， the differential compounds between the different fermentation samples were screened and identified. ResultsThe analysis of fungal community diversity showed that the dominant flora did not change at different fermentation time points in the traditional pressure-shelf fermentation method， while in the non-pressure-shelf natural fermentation method， there was a significant difference with the fermentation process， and at the genus level， the dominant genus of samples Y1， Y2， Y3 and F2 was Aspergillus， while the dominant genera of samples F1 and F3 were both Rhizopus. This indicated that the microbial growth environment provided by the traditional fermentation method was more stable， and the microbial community structure was more stable， which was more conducive to the stable and controllable fermentation process and fermented products. A total of 155 compounds were identified by compositional analysis， including 70 flavonoids， 38 coumarins， 10 alkaloids， 34 organic acids and 3 other compounds. After fermentation， two new components of ribalinine and pranferin were produced. Different fermentation conditions also brought about differences in chemical composition， multivariate statistical analysis obtained 26 differential compounds under two different fermentation methods， mainly including flavonoids， organic acids and coumarins. Comprehensively， the microbial community structure of samples fermented by the traditional pressure-shelf method of Aurantii Fructus for 14 d was stable， the species richness was high and the overall content of differential compounds was high， which was the optimal processing condition. ConclusionCompared with non-pressure-shelf natural fermentation， the traditional method has obvious advantages in terms of the stability of the microbial community structure and the content of chemical compounds， and the optimal condition is 14 days of fermentation. This study is helpful to promote the quality stability and fermentation bioavailability of fermented products of Aurantii Fructus， as well as to provide an experimental basis for the further improvement of the quality control methods of this variety.

ObjectiveTo investigate the effects of different fermentation methods and times on the fungal flora and chemical composition of Aurantii Fructus， in order to obtain the optimal fermentation conditions and flora structure， and to ensure the stability and controllability of the fermented varieties. MethodsScanning electron microscopy was used to observe and analyze the colony characteristics on the surface of Aurantii Fructus under different fermentation conditions. Internal transcribed spacer 2（ITS2） high-throughput sequencing， combined with fungal community diversity analysis and fungal community structure analysis， were used to obtain the fungal flora microbial categories of Aurantii Fructus under the conditions of traditional pressure-shelf fermentation and non-pressure-shelf natural fermentation for 7， 14， 21 d（numbered Y1-Y3 for the former， and numbered F1-F3 for the latter）， respectively. At the same time， the chemical components in the fermentation process were detected by ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry（UPLC-Q-TOF-MS/MS）， combined with principal component analysis（PCA）， partial least squares-discriminant analysis（PLS-DA） and compound retention time， parent ions， characteristic fragment ions and other information， the differential compounds between the different fermentation samples were screened and identified. ResultsThe analysis of fungal community diversity showed that the dominant flora did not change at different fermentation time points in the traditional pressure-shelf fermentation method， while in the non-pressure-shelf natural fermentation method， there was a significant difference with the fermentation process， and at the genus level， the dominant genus of samples Y1， Y2， Y3 and F2 was Aspergillus， while the dominant genera of samples F1 and F3 were both Rhizopus. This indicated that the microbial growth environment provided by the traditional fermentation method was more stable， and the microbial community structure was more stable， which was more conducive to the stable and controllable fermentation process and fermented products. A total of 155 compounds were identified by compositional analysis， including 70 flavonoids， 38 coumarins， 10 alkaloids， 34 organic acids and 3 other compounds. After fermentation， two new components of ribalinine and pranferin were produced. Different fermentation conditions also brought about differences in chemical composition， multivariate statistical analysis obtained 26 differential compounds under two different fermentation methods， mainly including flavonoids， organic acids and coumarins. Comprehensively， the microbial community structure of samples fermented by the traditional pressure-shelf method of Aurantii Fructus for 14 d was stable， the species richness was high and the overall content of differential compounds was high， which was the optimal processing condition. ConclusionCompared with non-pressure-shelf natural fermentation， the traditional method has obvious advantages in terms of the stability of the microbial community structure and the content of chemical compounds， and the optimal condition is 14 days of fermentation. This study is helpful to promote the quality stability and fermentation bioavailability of fermented products of Aurantii Fructus， as well as to provide an experimental basis for the further improvement of the quality control methods of this variety.

Objective:To discuss the effect of acupuncture on the differentiation and apoptosis of quadriceps muscle satellite cells in model rats with knee osteoarthritis(KOA),and to clarify its related mechanism.Methods:A total of 40 SPF-grade rats were selected and randomly divided into control group,model group,celecoxib group,and acupuncture group,with 10 rats in each group.The rats in control group only underwent joint cavity incision followed by suturing,while the rats in model group,celecoxib group,and acupuncture group were used to replicate the KOA models.The maximum circumference of the femoral segment of the affected limb,rat body mass,and quadriceps wet weight of the rats in various groups were measured;the quadriceps wet weight maintenance rate and quadriceps wet weight/body mass ratio of the rats in various groups were calculated.HE staining was used to observe the pathomorphology of articular cartilage and quadriceps muscle tissue of the rats in various groups;terminal deoxynucleotidyl transferase(TdT)-mediated dUTP nick end labeling(TUNEL)method was used to detect the apoptosis indexes in articular cartilage and quadriceps muscle tissue of the rats in various groups;immunofluorescence method was used to detect the protein expression levels of interleukin-6(IL-6),Janus kinase(JAK),and signal transducer and activator of transcription 3(STAT3)in quadriceps muscle tissue of the rats in various groups;Western blotting method was used to detect the expression levels of IL-6/JAK/STAT3 signaling pathway proteins,and muscle satellite cells,and apoptosis-related proteins in quadriceps muscle tissue of the rats in various groups.Results:Compared with control group,the affected hind limb circumference,quadriceps wet weight,wet weight maintenance rate,and wet weight/body mass ratio of the rats in model group were significantly decreased(P<0.05);compared with model group,the affected hind limb circumference,quadriceps wet weight,wet weight maintenance rate,and wet weight/body mass ratio of the rats in celecoxib group and acupuncture group were significantly increased(P<0.05);compared with celecoxib group,the affected hind limb circumference,quadriceps wet weight,wet weight maintenance rate,and wet weight/body mass ratio of the rats in acupuncture group were significantly increased(P<0.05).The HE staining results showed that the knee articular cartilage of the rats in control group remained intact,chondrocytes were aggregated and horizontally arranged with smooth edges,and quadriceps muscle cells were long cylindrical,orderly arranged,and regular in shape;in model group,the knee articular cartilage was thinner with rough edges,reduced number of cartilage layers,and disordered arrangement,and the quadriceps muscle fibers were disorganized,with some muscle fiber dissolution and muscle cell membrane damage,accompanied by muscle fiber fragments and a large amount of inflammatory exudate;in celecoxib group,the morphology of knee articular cartilage was generally normal,occasionally with irregular cartilage arrangement and reduced thickness,sporadically visible necrotic chondrocytes,quadriceps muscle fibers and sarcolemma were relatively intact,new muscle fibers appeared,some muscle fiber edges were blurred,accompanied by a small amount of cell debris and mild inflammatory infiltration;in acupuncture group,the knee articular cartilage structure remained intact with smooth edges,occasionally rough edges,and chondrocytes were aggregated and orderly arranged.The TUNEL assay results showed that compared with control group,the apoptosis indexes in articular cartilage and quadriceps muscle tissue of the rats in model group were significantly increased(P<0.05);compared with model group,the apoptosis indexes in articular cartilage and quadriceps muscle tissue of the rats in celecoxib group and acupuncture group were significantly decreased(P<0.05);compared with celecoxib group,the apoptosis index in articular cartilage and quadriceps muscle tissue of the rats in acupuncture group were significantly decreased(P<0.05).The immunofluorescence assay results showed that compared with control group,the expression levels of IL-6,JAK,and STAT3 proteins in quadriceps muscle tissue of the rats in model group were significantly decreased(P<0.05);compared with model group,the expression levels of IL-6,JAK,and STAT3 proteins in quadriceps muscle tissue of the rats in celecoxib group and acupuncture group were significantly increased(P<0.05);compared with celecoxib group,the expression levels of IL-6,JAK,and STAT3 proteins in quadriceps muscle tissue of the rats in acupuncture group were significantly increased(P<0.05).The Western blotting results showed that compared with control group,the expression levels of IL-6,JAK,STAT3,paired box transcription factor 7(Pax7),Desmin,Myosin,and Myogenin proteins in quadriceps muscle tissue of the rats in model group were significantly decreased(P<0.05);compared with model group,the expression levels of IL-6,JAK,STAT3,Pax7,Desmin,Myosin,and Myogenin proteins in quadriceps muscle tissue of the rats in celecoxib group and acupuncture group were significantly increased(P<0.05);compared with celecoxib group,the expression levels of IL-6,JAK,STAT3,Pax7,Desmin,Myosin,and Myogenin proteins in quadriceps muscle tissue of the rats in acupuncture group were significantly increased(P<0.05).Compared with control group,the expression levels of B-cell lymphoma 2(Bcl-2),B-cell lymphoma-xl(Bcl-xl),and myeloid cell leukemia 1(MCL1)proteins in quadriceps muscle tissue in model group were significantly decreased(P<0.05),and the expression levels of Bcl-2-associated X protein(Bax)and cysteinyl aspartate specific proteinase-3(Caspase-3)proteins were significantly increased(P<0.05);compared with model group,the expression levels of Bcl-2,Bcl-xl,and MCL1 proteins in quadriceps muscle tissue of the rats in celecoxib group and acupuncture group were significantly increased(P<0.05),and the expression levels of Bax and Caspase-3 proteins were significantly decreased(P<0.05);compared with celecoxib group,the expression levels of Bcl-2,Bcl-xl,and MCL1 proteins in quadriceps muscle tissue of the rats in acupuncture group were significantly increased(P<0.05),and the expression levels of Bax and Caspase-3 proteins were significantly decreased(P<0.05).Conclusion:Acupuncture can promote the differentiation of quadriceps muscle satellite cells and inhibit muscle cell apoptosis in the model rats with KOA,and the mechanism may be related to the up-regulation of expressions of IL-6,JAK,and STAT3 proteins in the quadriceps muscle tissue.

Objective:To explore the deubiquitination modification of the deubiquitinase BRCC3 in rats with neuropathic pain (NPP) treated with meridian tuina of Zhuang medicine and its analgesic molecular mechanism.Methods:Rats were divided into normal group, sham-operation group, model group, sham-tuina group, and meridian tuina of Zhuang medicine group using a random number table method, with 9 rats in each group. Except for the normal and sham operation groups, spinal nerve ligation models were prepared in all other groups. On the first day after surgery, intervention was carried out on the meridian tuina of Zhuang medicine and sham-tuina groups for 14 days, while the other three groups were not intervened; the paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) of each group of rats were measured at 0 days before operation, 1, 7, and 14 days after operation. Western blot was used to detect the expressions of BRCC3 and NLRP3 proteins in spinal cord tissue, and ELISA was used to detect the level of IL-1β in serum.Results:On postoperative 7 and 14 d, compared with the model group, the meridian tuina of Zhuang medicine group showed an increase in PWMT and PWTL, a decrease in NLPR3 and BRCC3 expression in spinal cord tissue, and a decrease in serum IL-1β levels ( P<0.05). Compared with the sham-tuina group, the meridian tuina of Zhuang medicine group showed an increase in PWMT and PWTL, a decrease in NLRP3 protein expression in spinal cord tissue, and a decrease in IL-1β levels in serum ( P<0.05). Conclusion:Meridian tuina of Zhuang medicine can alleviate pain sensitivity in SNL model rats, and its mechanism is related to the inhibition of the expression of deubiquitinase BRCC3 by meridian massage of Zhuang medicine, which increases the ubiquitination level of NLRP3 and hinders its activation, thereby blocking the immune inflammatory response mediated by inflammatory factors.

Objective: To investigate the effects and mechanisms of Astragalus Polysacharin(APS) on the proliferation and metastasis of breast cancer cells by regulating miR-107 and miR-346-mediated macrophage polarization in breast cancer-derived exosomes. Methods: Forty 8-week-old female BALB/c mice were selected and breast cancer xenograft models and 4T1 transplanted tumor models were established. The mice were divided into the control group and the APS group. The APS group mice received daily intragastric administration of APS for 25 days, while the control group mice were given the same amount of normal saline. After all treatments were completed, the mice were euthanized, and tumor tissues were isolated. Western blot and flow cytometry were used to detect the expressions of proliferating cell nuclear antigen(PCNA), Ki-67, CD206, CD163, inducible nitric-oxide synthase(iNOS), and CD86. The apoptosis of single-cell suspensions in tumor tissues was analyzed. Human breast cancer cell line MDA-MB-231 was cultured and stimulated with APS, and exosomes from the cell culture medium were collected. The proliferation, migration, and invasion of cells were detected by CCK-8 assay, scratch assay, permeability chamber cell invasion assay, and qRT-PCR. Differentially expressed genes were screened by bioinformatics. Results : By measuring the expressions of molecules related to breast cancer cell proliferation and metastasis, it was shown that APS treatment reduced the expressions of proliferation-related proteins(PCNA and Ki-67) and metastasis-related proteins(Vimentin) in MDA-MB-231 xenograft tumor tissues; and the polarization of tumor-associated macrophages was observed. APS treatment of 4T1 transplanted tumor tissues could reduce the number of M2 macrophages and increase the number of M1 macrophages, resulting in a decrease in the ratio of M2/M1 macrophages and an increase in cell apoptosis in 4T1 transplanted tumor tissues. The expressions of related proteins iNOS and CD86 increased, and CD206 and CD163 decreased. After APS treatment, the exosomes produced by MDA-MB-231 reduced the polarization of M2 macrophages and affected the expressions of miR-107 and miR-346. Conclusion APS inhibits the polarization of M2 macrophages by regulating the expression of miR-107 or miR-346 in breast cancer cell-derived exosomes, ultimately inhibiting the proliferation and metastasis of breast cancer cells.

[Objective]To analyze the current research status and hot topics of traditional Chinese medicine(TCM)in the treatment of multiple sclerosis(MS),and provide references for clinical decision-making,future research and the construction of integrated Chinese and western medicine treatment guidelines.[Methods]Relevant literature published from January 2004 to November 2024 was retrieved from the CNKI,VIP,Wanfang,PubMed and Web of Science(WOS)databases.Using CiteSpace 6.3.R1 software,a visual analysis was performed on publication time,authors,institutions and keywords through co-occurrence,clustering and burst analysis to derive the current research status and hot topics.[Results]A total of 168 articles were included.The number of publications in the field of TCM treatment for MS remained relatively stable in recent years,but the proportion of high-quality clinical studies increased.A stable core group of authors was not yet formed,and research institutions were concentrated in major university-affiliated hospitals and traditional Chinese medicine institutions.High-frequency and high-centrality keywords included syndrome differentiation and treatment,renowned physician experience,integrative Chinese and western medicine,etiology and pathogenesis,and TCM syndromes.[Conclusion]TCM treatment for MS is still in the development stage,with a focus on research related to etiology,pathogenesis and syndrome differentiation.Future efforts should emphasize team and institutional collaborations,development of multi-center networks,improvement of research quality,and exploration of interdisciplinary and multi-modal treatment approaches.High-quality evidence-based research should be promoted to inform clinical decision-making,improve treatment protocols,and contribute to the development of integrated Chinese and western medicine treatment guidelines.

Vertebral refracture following percutaneous vertebral augmentation (PVA) is commonly seen in elderly patients with osteoporotic thoracolumbar compression fractures (OTLCF). It can lead to recurrent pain, loss of vertebral height, progression of kyphosis, and even neurological dysfunction, significantly impairing patients′ quality of life. Current diagnosis and treatment face multiple challenges, including high misdiagnosis rate, difficulty in choosing between surgical and non-surgical treatment options, lack of standardized surgical protocols, interference from intralesional bone cement during procedures, inadequate stability of internal fixation in osteoporotic bone, and suboptimal compliance of anti-osteoporotic therapy. Establishing a standardized diagnostic and therapeutic framework is urgently needed. To standardize the management process and improve outcomes for vertebral refractures after PVA in elderly OTLCF patients, Spinal Trauma Group of the Orthopedic Branch of Chinese Medical Doctor Association organized experts in the field to develop Guideline for the diagnosis and treatment of vertebral refracture after percutaneous vertebral augmentation in elderly patients with osteoporotic thoracolumbar compression fractures ( version 2025), based on current literature and clinical experience, and adhering to principles of scientific rigor and clinical applicability. A total of 11 recommendations were proposed, encompassing diagnosis, treatment, and rehabilitation of vertebral refracture after PVA in elderly patients with OTLCF, aiming to provide a foundation for a standardized management.

Objective:To investigate the effects of chronic persistent hypoxia on hepatic function, histological morphology, and ultrastructure in aged mice, and to evaluate the protective role of pyrroloquinoline quinone(PQQ).Methods:Thirty-two 2-month-old (young group)and thirty-two 18-month-old(aged group)male C57BL6/J mice were each randomly divided into four groups (n=8 per group): normoxia+ normal saline (NS)group, normoxia+ PQQ group, hypoxia+ NS group, and hypoxia+ PQQ group.The normoxia+ NS and normoxia+ PQQ groups were housed under normoxic conditions[fraction of inspired oxygen(FiO 2)=21%], while the hypoxia+ NS and hypoxia+ PQQ groups were continuously exposed to a hypoxic environment[FiO 2=(10±0.5)%]simulated by a custom-made hypoxic chamber, maintaining a constant oxygen concentration for 24 hours per day.The normoxia+ NS and hypoxia+ NS groups received daily intragastric administration of NS, whereas the normoxia+ PQQ and hypoxia+ PQQ groups received daily intragastric administration of PQQ disodium salt(8 mg·kg -1·d -1).After 8 weeks of continuous intervention, blood samples were collected to measure red blood cell count, hemoglobin levels, and liver function-related biochemical indicators.Lung tissues were processed for HE staining, and liver tissues were processed for both HE staining and electron microscopy.The histological and ultrastructural features of each group were observed under light and electron microscopy, respectively, and the differences between the groups were compared and analyzed. Results:Compared with the normoxia+ NS groups, both young and aged hypoxia+ NS groups exhibited significant pulmonary arteriole narrowing( P<0.001), with markedly elevated red blood cell count and hemoglobin levels (all P<0.001), which were not alleviated by PQQ.Compared with the young normoxia+ NS group, the young hypoxia+ NS group showed significantly higher alanine aminotransferase (ALT)and lactate dehydrogenase (LDH)levels( Z=2.72, 2.53, P=0.007, 0.011), whereas the young hypoxia+ PQQ group exhibited LDH levels similar to those of the young normoxia+ NS group.The aged hypoxia+ NS group exhibited significant ALT elevation( t=2.66, P=0.013)compared with the aged normoxia+ NS group.Light microscopy revealed hepatocyte ballooning degeneration, mild fatty accumulation, and focal necrosis around central veins in the young hypoxia+ NS group, while the young hypoxia+ PQQ group exhibited no significant pathological damage but displayed numerous deeply stained binucleated hepatocytes.The aged normoxia+ NS group demonstrated hepatocyte ballooning degeneration and inflammatory cell infiltration around central veins, whereas the aged normoxia+ PQQ group exhibited no obvious pathological damage with scattered deeply stained binucleated hepatocytes.The aged hypoxia+ NS group exhibited significant necrosis following physiological oxygen concentration gradient distribution, while the aged hypoxia+ PQQ group displayed no obvious pathological damage with scattered deeply stained binucleated hepatocytes.Electron microscopy revealed that the aged normoxia+ NS group had reduced mitochondrial electron density ( P<0.001)and less developed rough endoplasmic reticulum compared with the young normoxia+ NS group.The young hypoxia+ NS group exhibited a smaller mitochondrial area( P<0.001), decreased mitochondrial matrix electron density( P<0.001), blurred or absent mitochondrial cristae, inactive rough endoplasmic reticulum, and increased accumulation of glycogen and lipid droplets compared with the young normoxia+ NS group, while the young hypoxia+ PQQ group maintained mitochondrial matrix electron density comparable to the young normoxia+ NS group.The aged hypoxia+ NS group exhibited larger mitochondrial area( P=0.001), decreased mitochondrial matrix electron density( P<0.001), blurred or absent mitochondrial cristae, mitochondrial edema, increased lysosomes, and elevated cytoplasmic electron density compared with the aged normoxia+ NS group.The aged hypoxia+ PQQ group exhibited reduced mitochondrial area( P<0.001)and restored mitochondrial matrix electron density to levels comparable with the aged normoxia+ NS group.The aged normoxia+ PQQ group demonstrated increased mitochondrial matrix electron density compared with the aged normoxia+ NS group( P<0.001). Conclusions:Chronic persistent hypoxia induces hepatic functional, histological and ultrastructural damage in mice, with more pronounced effects in aged animals.PQQ provides a certain degree of protection against these injuries.