[摘 要] 目的：探讨干扰素刺激基因家族成员黏病毒抵抗蛋白2（MX2）在调控肿瘤细胞对呼肠孤病毒（Reo）溶瘤敏感性中的作用及其机制。方法：选取4株具有不同耐药特征的人源肿瘤细胞，通过CCK-8法评估其对Reo的溶瘤敏感性；通过转录组测序筛选出差异表达基因MX2，qPCR法及WB法验证MX2在4株人源肿瘤细胞中的表达；使用siRNA敲低溶瘤低敏感的COC1/DDP细胞中的MX2基因。在细胞感染Reo病毒后，通过CCK-8法检测细胞存活率；qPCR法检测细胞中Reo病毒S1基因表达；免疫荧光法检测细胞内Reo病毒蛋白的积累；半数组织培养感染剂量（TCID50）法测定病毒滴度；流式细胞术分别检测细胞内Reo病毒dsRNA、活性氧（ROS）水平以及细胞凋亡率；透射电镜观察细胞内质网形态变化并采用WB法检测内质网应激相关蛋白（JNK、p-JNK、eIF2α、p-eIF2α、CHOP、PERK）的表达。结果：在4株肿瘤细胞中，SKOV3细胞对Reo溶瘤作用高度敏感，而COC1/DDP、HuH-7SRB及SNU-398细胞均为溶瘤低敏感性。转录组测序结果显示，MX2在溶瘤低敏感肿瘤细胞中的表达水平显著高于溶瘤高敏感细胞（P < 0.01）；在溶瘤低敏感性的COC1/DDP细胞中，敲低MX2显著促进Reo病毒复制、诱导细胞凋亡增加，并升高细胞内活性氧水平（均P < 0.001）。透射电镜观察显示，敲低MX2的COC1/DDP细胞感染Reo病毒后出现内质网肿胀、扩张及断裂等典型内质网应激超微结构改变。WB结果显示，内质网应激关键标志物eIF2α/p-eIF2α、PERK、CHOP及凋亡相关调节蛋白JNK/p-JNK的表达均显著上调（P < 0.05或P < 0.01）。结论：肿瘤细胞对Reo的溶瘤敏感性与其细胞内MX2表达水平密切相关。敲低MX2可显著增强Reo在细胞内的复制，进而促进ROS积累，触发内质网应激并促进凋亡。病毒复制增加与细胞凋亡激活的双重作用，最终协同增强Reo的溶瘤作用。

ObjectiveThis study aimed to investigate whether Bushen Tongluo prescription inhibits macrophage polarization by regulating the Wnt3a/β-catenin signaling pathway， thereby reducing epithelial-mesenchymal transition and excessive extracellular matrix deposition， in order to elucidate the anti-pulmonary fibrosis mechanisms of Bushen Tongluo prescription and provide a new theoretical basis for the clinical treatment of pulmonary fibrosis. MethodsFifty male Sprague-Dawley （SD） rats were randomly divided into a blank group， model group， pirfenidone group， and high- and low-dose Bushen Tongluo prescription groups. Except for the blank group， the pulmonary fibrosis model was established by intratracheal instillation of bleomycin. Intervention was initiated on day 28 after modeling. The high- and low-dose Bushen Tongluo prescription groups were administered Bushen Tongluo prescription at doses of 30.88， 15.44 g·kg^-1， respectively， by intragastric gavage. The pirfenidone group was administered pirfenidone capsules at 110 mg·kg^-1 by intragastric gavage. The blank and model groups were given an equal volume of normal saline by gavage， once daily for 90 days. After treatment， the level of transforming growth factor-β₁ （TGF-β₁） in bronchoalveolar lavage fluid （BALF） was detected by enzyme-linked immunosorbent assay （ELISA）. Morphological changes in lung tissue and the collagen volume fraction were compared. The protein distribution and expression of E-cadherin， cytokeratin 19， α-smooth muscle actin （α-SMA）， vimentin， collagen type Ⅰ （Col Ⅰ）， and collagen type Ⅲ （Col Ⅲ） in lung tissue were detected by immunohistochemistry. The protein distribution and expression of CD68， arginase-1 （Arg-1）， inducible nitric oxide synthase （iNOS）， Wnt3a， and β-catenin in lung tissue were detected by immunofluorescence. The protein expression of Wnt3a and β-catenin in lung tissue was detected by Western blot， and the mRNA expression of Wnt3a and β-catenin was detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. ResultsCompared with the blank group， a large number of inflammatory cells infiltrated the airway walls， alveolar spaces， and interstitial tissue in the model group， with obvious fibrous tissue hyperplasia. The level of TGF-β₁ in BALF was significantly increased. The protein expression of E-cadherin and cytokeratin 19 in lung tissue was decreased， whereas the protein expression of α-SMA， Vimentin， Wnt3a， β-catenin， Col Ⅰ， and Col Ⅲ was increased. The fluorescence-positive area ratios of CD68， Arg-1， iNOS， Wnt3a， and β-catenin in lung tissue were increased. The protein and mRNA expression levels of Wnt3a and β-catenin in lung tissue were significantly increased （P<0.01）. Compared with the model group， all treatment groups showed varying degrees of improvement in inflammatory cell infiltration and fibrous tissue hyperplasia in the airway walls， alveolar spaces， and interstitial tissue， decreased TGF-β₁ levels in BALF， increased protein expression of E-cadherin and cytokeratin 19 in lung tissue， decreased protein expression of α-SMA， Vimentin， Col Ⅰ， and Col Ⅲ， decreased fluorescence-positive area ratios of CD68， Arg-1， iNOS， Wnt3a， and β-catenin in lung tissue， and decreased protein and mRNA expression levels of Wnt3a and β-catenin in lung tissue （P<0.05， P<0.01）. ConclusionBushen Tongluo prescription can improve bleomycin-induced pulmonary fibrosis in rats by inhibiting epithelial-mesenchymal transition and reducing excessive extracellular matrix deposition. The mechanism may be related to inhibition of the Wnt3a/β-catenin signaling pathway and the macrophage polarization mediated by this pathway.

Background Meteorological factors are among the key extrinsic triggers for the onset and exacerbation of cardiovascular and cerebrovascular diseases (CVD). Against the backdrop of sustained global warming, elucidating the impact of ambient temperature and atmospheric pressure on CVD, especially on pre-hospital CVD emergent events, has become imperative for evidence-based prevention and emergency preparedness. Objective To quantify the temporal trends of daily mean temperature and atmospheric pressure and their associations with pre-hospital CVD emergent events in Yantai, and to explore effect modification by demographic subgroups and geographic areas, thereby providing an empirical basis for the rational allocation of emergency medical resources. Methods Pre-hospital CVD emergency data from January 1, 2016 to December 31, 2022 were selected from the Yantai 120 Emergency Medical Command System. Synchronous meteorological factors and environmental pollutant data were obtained from the websites of the National Oceanic and Atmospheric Administration and the National Centers for Environmental Information of the United States. Time-series analysis combined with distributed lag non-linear model was used to analyze the association between daily temperature, atmospheric pressure, and pre-hospital CVD emergencies. Average annual percentage changes (AAPC) were calculated using Joinpoint (version 5.2.0.0) to reflect temporal trends. Spearman correlation analysis was employed to screen variables with low collinearity for inclusion in the multi-pollutant adjusted models. Results From 2016 to 2022, a total of 268275 pre-hospital CVD emergency cases were recorded in Yantai City, showing an increasing annual trend (AAPC=7.16%, P=0.002). Emergency volume, daily temperature, atmospheric pressure, and PM₁₀ displayed marked seasonal patterns, with summer bottoms and winter peaks for emergencies, daily temperature higher in summer and lower in winter, and the inverse for atmospheric pressure. Correlation analysis showed that both daily temperature and atmospheric pressure were positively correlated with O₃, with correlation coefficients of 0.745 and 0.723, respectively; negatively correlated with PM_2.5, with correlation coefficients of −0.246 and −0.235, respectively; and negatively correlated with PM₁₀, with correlation coefficients of −0.241 and −0.229, respectively (P < 0.05). A U-shaped correlation was revealed between daily temperature and pre-hospital CVD emergency risk. Using 24 °C as the reference, risk was elevated at both low and high daily temperatures, with the strongest cold effect at –11 ℃ (RR=1.53, 95%CI: 1.35, 1.73) and strongest heat effect at 30 ℃ (RR=1.06, 95%CI: 1.01, 1.11); cold effects were prolonged (lag0–14d) compared to heat effects. Atmospheric pressure exhibited a positive association with emergencies; using a median of 1012.2 hPa as the reference, the maximum risk occurred at 1037 hPa (RR=1.25, 95%CI: 1.03, 1.52), with a 0–5 d lag. In the subgroup analysis, the impact of low temperature was more pronounced among females (RR_{−9 ℃}=1.66), people over 60 years (RR_{−9 ℃}=1.91), and rural residents (RR_{−9 ℃}=1.76). High atmospheric pressure significantly increased the risk of pre-hospital CVD emergency among females (RR_{1035 hPa}=1.54), people under 18 years (RR_{1035 hPa}=3.62), and rural residents (RR_{1035 hPa}=1.46). The sensitivity analysis results indicated that, after excluding the impact of pandemic and the degrees of freedom for time variations, the effects of daily average temperature and atmospheric pressure on pre-hospital CVD emergency volume were consistent with the primary analysis findings. Conclusion Both non-optimal temperature and atmospheric pressure significantly increase the pre-hospital CVD emergency volume; therefore, emergency medical services should develop targeted response protocols, optimize resource allocation, and intensify public health education to mitigate the pre-hospital burden attributable to temperature and pressure fluctuations.

BACKGROUND:Sarcopenia is an age-related condition characterized by the loss of skeletal muscle mass,strength,and/or physical function.Currently,effective treatments for sarcopenia remain limited.A new therapeutic approach to improve symptoms and prognosis of sarcopenia patients clinically was important.OBJECTIVE:To explore the effects of canine adipose-derived mesenchymal stem cells and their exosomes on a dexamethasone-induced sarcopenia in mice.METHODS:Mesenchymal stem cells were isolated and cultured from canine adipose tissue,and identified and functionally evaluated through flow cytometry and differentiation assays for osteogenesis,adipogenesis,and chondrogenesis.Subsequently,exosomes from adipose-derived mesenchymal stem cells were extracted and characterized using transmission electron microscopy,western blot assay,and nanocoulter tracking analysis.In vitro,the effects of canine adipose-derived mesenchymal stem cells and their exosomes on myotube growth and the expression of muscle atrophy-related genes were investigated using dexamethasone-induced C2C12 myotube atrophy and aging C2C12 models.In vivo,a dexamethasone-induced mouse sarcopenia model was established and received intraperitoneal or intravenous injection of canine adipose-derived mesenchymal stem cells.Therapeutic efficacy was assessed through mouse rotarod performance,histopathological analysis,and muscle atrophy-related genes testing.RESULTS AND CONCLUSION:(1)The isolated canine adipose-derived mesenchymal stem cells highly expressed CD73,CD90,and CD105,and lowly expressed MHC-Ⅱ,CD14,CD19,CD34,and CD45,and successfully differentiated into osteoblasts,adipocytes,and chondrocytes in vitro.(2)The adipose-derived mesenchymal stem cells-derived exosomes met the identification criteria in terms of particle size,electron microscopy morphology,and positive expression of specific markers.(3)Compared to the dexamethasone-induced C2C12 atrophy group,treatment with adipose-derived mesenchymal stem cells and their exosomes promoted the recovery and growth of myotubes,inhibited the expression of muscle atrophy-related genes MuRF1 and Atrogin-1.(4)Compared to the aging C2C12 group,adipose-derived mesenchymal stem cells and their exosomes significantly enhanced the recovery and growth of aged muscle tubes in aging cells.(5)Compared to the control group,the rotarod time in dexamethasone-induced sarcopenia model mice was significantly decreased(P＜0.01).After 7 days(P＜0.01,P＜0.01)and 10 days(P＜0.01,P＜0.05)of adipose-derived mesenchymal stem cells treatment via intraperitoneal and intravenous injection,rotarod time was significantly increased,respectively.After 14 days,all treatment groups showed longer rotarod times than the model group,although with no significant differences between them.(6)Compared to the control group,the cross-sectional area of anterior tibial muscle in the model group was significantly reduced(P＜0.01),and it was significantly increased after intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells(P＜0.05,P＜0.01).(7)Compared to the model group,intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells significantly inhibited the mRNA expression of MuRF1 and Atrogin-1 genes(P＜0.01,P＜0.01,P＜0.01,P＜0.01).The results indicated that adipose-derived mesenchymal stem cells and their exosomes promoted recovery and growth of atrophic myotube cells by inhibiting the expression of muscle atrophy-related genes,and both intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells provided good therapeutic effects on sarcopenia in mice.

BACKGROUND:Sarcopenia is an age-related condition characterized by the loss of skeletal muscle mass,strength,and/or physical function.Currently,effective treatments for sarcopenia remain limited.A new therapeutic approach to improve symptoms and prognosis of sarcopenia patients clinically was important.OBJECTIVE:To explore the effects of canine adipose-derived mesenchymal stem cells and their exosomes on a dexamethasone-induced sarcopenia in mice.METHODS:Mesenchymal stem cells were isolated and cultured from canine adipose tissue,and identified and functionally evaluated through flow cytometry and differentiation assays for osteogenesis,adipogenesis,and chondrogenesis.Subsequently,exosomes from adipose-derived mesenchymal stem cells were extracted and characterized using transmission electron microscopy,western blot assay,and nanocoulter tracking analysis.In vitro,the effects of canine adipose-derived mesenchymal stem cells and their exosomes on myotube growth and the expression of muscle atrophy-related genes were investigated using dexamethasone-induced C2C12 myotube atrophy and aging C2C12 models.In vivo,a dexamethasone-induced mouse sarcopenia model was established and received intraperitoneal or intravenous injection of canine adipose-derived mesenchymal stem cells.Therapeutic efficacy was assessed through mouse rotarod performance,histopathological analysis,and muscle atrophy-related genes testing.RESULTS AND CONCLUSION:(1)The isolated canine adipose-derived mesenchymal stem cells highly expressed CD73,CD90,and CD105,and lowly expressed MHC-Ⅱ,CD14,CD19,CD34,and CD45,and successfully differentiated into osteoblasts,adipocytes,and chondrocytes in vitro.(2)The adipose-derived mesenchymal stem cells-derived exosomes met the identification criteria in terms of particle size,electron microscopy morphology,and positive expression of specific markers.(3)Compared to the dexamethasone-induced C2C12 atrophy group,treatment with adipose-derived mesenchymal stem cells and their exosomes promoted the recovery and growth of myotubes,inhibited the expression of muscle atrophy-related genes MuRF1 and Atrogin-1.(4)Compared to the aging C2C12 group,adipose-derived mesenchymal stem cells and their exosomes significantly enhanced the recovery and growth of aged muscle tubes in aging cells.(5)Compared to the control group,the rotarod time in dexamethasone-induced sarcopenia model mice was significantly decreased(P＜0.01).After 7 days(P＜0.01,P＜0.01)and 10 days(P＜0.01,P＜0.05)of adipose-derived mesenchymal stem cells treatment via intraperitoneal and intravenous injection,rotarod time was significantly increased,respectively.After 14 days,all treatment groups showed longer rotarod times than the model group,although with no significant differences between them.(6)Compared to the control group,the cross-sectional area of anterior tibial muscle in the model group was significantly reduced(P＜0.01),and it was significantly increased after intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells(P＜0.05,P＜0.01).(7)Compared to the model group,intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells significantly inhibited the mRNA expression of MuRF1 and Atrogin-1 genes(P＜0.01,P＜0.01,P＜0.01,P＜0.01).The results indicated that adipose-derived mesenchymal stem cells and their exosomes promoted recovery and growth of atrophic myotube cells by inhibiting the expression of muscle atrophy-related genes,and both intraperitoneal and intravenous administration of adipose-derived mesenchymal stem cells provided good therapeutic effects on sarcopenia in mice.

ObjectiveTo clarify whether METTL14 mediates the core role of acupuncture at Neiguan (PC6) in promoting myelination and improving behavior in young autistic rats through gene intervention technology. MethodsThe ASD model was established by intraperitoneal injection of valproic acid (VPA) in pregnant rats. Male offspring were intracerebroventricularly injected with adenovirus-packaged METTL14 shRNA (sh-METTL14) or its control (sh-NC) on postnatal day 1, with a model group set as well. Subsequently, the juvenile rats were divided into model group, acupuncture group, acupuncture+sh-NC group, and acupuncture+sh-METTL14 group. The acupuncture group received acupuncture at Neiguan (PC6) from postnatal day 7, once daily for 21 consecutive days. Neurobehavioral changes were evaluated by behavioral tests; METTL14 knockdown efficiency and the expression of METTL14, METTL3, and PTEN were detected by quantitative real-time PCR (qRT-PCR) and Western blot (WB); PTEN m⁶A levels were measured by RNA immunoprecipitation-qPCR (RIP-qPCR); myelin ultrastructure, expression of myelin basic protein (MBP) and neurofascin 155 (NF155), and dendritic spine density were observed using transmission electron microscopy (TEM), enzyme-linked immunosorbent assay (ELISA), immunofluorescence, qRT-PCR, and primary neuron culture. ResultsBehaviorally, knockdown of METTL14 significantly counteracted the beneficial effects of acupuncture in improving self-grooming, open field exploration, three-chamber social interaction, and Morris water maze learning and memory (P<0.05, P<0.01). Compared with the acupuncture+sh-NC group, the acupuncture+sh-METTL14 group showed significantly decreased mRNA and protein expression of hippocampal METTL14 (P<0.01), and the upregulating effects of acupuncture on METTL3 and PTEN expression were reversed (P<0.01). Meanwhile, knockdown of METTL14 significantly inhibited the acupuncture-induced increase in PTEN m⁶A levels (P<0.01). Morphologically, knockdown of METTL14 attenuated the improvement of myelin structure by acupuncture, reversed the downregulation of MBP and upregulation of NF155 induced by acupuncture, and blocked the increase in dendritic spine density (P<0.05, P<0.01). ConclusionMETTL14 is a key molecule mediating the therapeutic effect of acupuncture at Neiguan. Acupuncture at Neiguan upregulates METTL14, thereby enhancing m⁶A methylation modification of PTEN mRNA to stabilize its expression, ultimately promoting myelin development and improving behavioral symptoms in ASD juvenile rats. This preliminarily reveals the modern biological connotation of “opening Xuanfu and dredging myelin”.

ObjectiveTo clarify whether METTL14 mediates the core role of acupuncture at Neiguan (PC6) in promoting myelination and improving behavior in young autistic rats through gene intervention technology. MethodsThe ASD model was established by intraperitoneal injection of valproic acid (VPA) in pregnant rats. Male offspring were intracerebroventricularly injected with adenovirus-packaged METTL14 shRNA (sh-METTL14) or its control (sh-NC) on postnatal day 1, with a model group set as well. Subsequently, the juvenile rats were divided into model group, acupuncture group, acupuncture+sh-NC group, and acupuncture+sh-METTL14 group. The acupuncture group received acupuncture at Neiguan (PC6) from postnatal day 7, once daily for 21 consecutive days. Neurobehavioral changes were evaluated by behavioral tests; METTL14 knockdown efficiency and the expression of METTL14, METTL3, and PTEN were detected by quantitative real-time PCR (qRT-PCR) and Western blot (WB); PTEN m⁶A levels were measured by RNA immunoprecipitation-qPCR (RIP-qPCR); myelin ultrastructure, expression of myelin basic protein (MBP) and neurofascin 155 (NF155), and dendritic spine density were observed using transmission electron microscopy (TEM), enzyme-linked immunosorbent assay (ELISA), immunofluorescence, qRT-PCR, and primary neuron culture. ResultsBehaviorally, knockdown of METTL14 significantly counteracted the beneficial effects of acupuncture in improving self-grooming, open field exploration, three-chamber social interaction, and Morris water maze learning and memory (P<0.05, P<0.01). Compared with the acupuncture+sh-NC group, the acupuncture+sh-METTL14 group showed significantly decreased mRNA and protein expression of hippocampal METTL14 (P<0.01), and the upregulating effects of acupuncture on METTL3 and PTEN expression were reversed (P<0.01). Meanwhile, knockdown of METTL14 significantly inhibited the acupuncture-induced increase in PTEN m⁶A levels (P<0.01). Morphologically, knockdown of METTL14 attenuated the improvement of myelin structure by acupuncture, reversed the downregulation of MBP and upregulation of NF155 induced by acupuncture, and blocked the increase in dendritic spine density (P<0.05, P<0.01). ConclusionMETTL14 is a key molecule mediating the therapeutic effect of acupuncture at Neiguan. Acupuncture at Neiguan upregulates METTL14, thereby enhancing m⁶A methylation modification of PTEN mRNA to stabilize its expression, ultimately promoting myelin development and improving behavioral symptoms in ASD juvenile rats. This preliminarily reveals the modern biological connotation of “opening Xuanfu and dredging myelin”.

ObjectiveThis paper aims to investigate the distribution patterns of traditional Chinese medicine syndromes in patients with chronic hepatitis B （CHB） comorbid with metabolically associated fatty liver disease （MAFLD） and analyze their correlation with clinical characteristics and the progression of liver fibrosis. MethodsA cross-sectional study method was employed， and 506 patients with CHB comorbid with MAFLD who attended the Hepatology Outpatient Department of Public Health Clinical Center of Chengdu from June 2024 to December 2024 were enrolled. General information， traditional Chinese medicine syndromes information， laboratory indicators， and imaging examination results were collected using case report forms （CRF）. Tongue images of patients were acquired using a tongue diagnosis instrument， and tongue feature parameters were extracted using computer image processing technology. Frequency analysis， factor analysis， and cluster analysis， and other methods were used to explore syndrome categories and distribution patterns. Non-parametric tests were used to compare the differences in clinical characteristics among different syndromes. Univariate and multivariate logistic regression analyses were performed to investigate the correlation between traditional Chinese medicine syndromes and the progression of liver fibrosis. ResultsThe main traditional Chinese medicine syndromes in patients with CHB comorbid with MAFLD were mainly dominated by damp-heat accumulation syndrome， liver stagnation and spleen deficiency syndrome， and phlegm-blood stasis syndrome， with damp-heat accumulation syndrome accounting for the highest proportion （41.89%）. Compared with those without damp-heat accumulation syndrome， patients with damp-heat accumulation syndrome had significantly lower tongue proper H value， tongue coating H value， and tongue coating a^* value （P<0.05）， significantly higher tongue coating b^* value （P<0.05）， significantly increased levels of white blood cell （WBC）， red blood cell （RBC）， hemoglobin （HGB）， and glucose （GLU）， increased CAP values （P<0.05）， a higher proportion of males （P<0.05）， and a younger age （P<0.05）. Univariate and multivariate logistic regression analyses show that age， hepatitis B surface antigen （HBsAg）， diabetes， and damp-heat accumulation syndrome are independent risk factors for liver fibrosis （P<0.05）， and that damp-heat accumulation syndrome is predominantly distributed in liver fibrosis stage F0-F1. ConclusionDamp-heat accumulation syndrome is a typical syndrome in patients with CHB comorbid with MAFLD， which is significantly associated with enhanced inflammatory response， metabolic disorders， and early liver fibrosis， and is a key link in disease progression. Clinical attention and early intervention are needed.

ObjectiveTo reveal the molecular mechanism by which the traditional Chinese medicine compound prescription Qiangjing tablets regulate the aging of the testicular tissue and Leydig cells in rats through the cyclin-dependent kinase 4 （CDK4）-early 2 factor （E2F） signaling pathway. MethodsFor the cell experiment， 2-month-old SPF-grade SD male rats were selected and randomly assigned into a blank control group （administrated with an equal volume of 0.9% sodium chloride injection） and a Qiangjing tablets group （20 rats in each group） according to body weight. The Leydig cell model of aging was established by treatment of TM3 cells with 100 μmol·L^-1 H₂O₂， and the modeling performance was evaluated based on the levels of p16 and p21 determined by Western blot. The antioxidant NAC （1 mmol·L^-1） was used as the positive control for eliminating reactive oxygen species （ROS）. Cells were intervened with Qiangjing tablets-containing serum at low （2.5%）， medium （5%）， and high （10%） concentrations. The testosterone level in the cell supernatant was determined by enzyme-linked immunosorbent assay （ELISA）， and the protein levels of CDK4， E2F1， and E2F2 were analyzed by Western blot. In the animal experiment， 19-month-old naturally aging rats were used as the model group， and 2-month-old rats as the young control group. The positive control group was subcutaneously injected with 5.21 mg·kg^-1·d^-1 testosterone propionate. Qiangjing tablets were administered by gavage at low， medium， and high doses of 0.72， 1.44， 2.88 g·kg^-1·d^-1， respectively. The general conditions of rats were observed， and the protein levels of CDK4， E2F1， and E2F2 in the testicular tissue were determined by Western blot. ResultsIn the cell experiment， compared with the blank control group， the model group showed upregulated expression of CDK4 and E2F1 （P<0.05） and slightly downregulated expression of E2F2. Compared with that in the model group， the expression of CDK4 was upregulated in the NAC group and the low-dose Qiangjing tablets group （P<0.05）， slightly upregulated in the medium-dose Qiangjing tablets group， and downregulated in the high-dose Qiangjing tablets group （P<0.05）. The NAC group showed downregulated expression of E2F1 （P<0.05） and E2F2， and the low-， medium-， and high-dose Qiangjing tablets groups showed downregulated expression of both E2F1 and E2F2 （P<0.05）. Compared with that in the NAC group， the expression of CDK4 was upregulated in the low-dose Qiangjing tablets group and downregulated in the medium-dose and high dose （P<0.05） groups. The expression of E2F1 was down-regulated in all the three dose groups， with statistically significance in the high dose group （P<0.05）， and that of E2F2 were downregulated in all the three dose groups （P<0.05）. In the animal experiment， compared with the young control group， the model group exhibited downregulated expression of CDK4 （P<0.05） and slightly upregulated expression of E2F1 and E2F2. Compared with that in the model group， the expression of CDK4 decreased in the testosterone propionate group and the low-dose Qiangjing tablets group （P<0.05） but increased in the medium-dose （P<0.05） and high-dose groups. In addition， the expression of E2F1 decreased （P<0.05）， and that of E2F2 was slightly elevated. Compared with that in the NAC group， CDK4 expression was elevated in the Qiangjing tablets groups， with statistical significance in the medium- and high-dose groups （P<0.05）. Similarly， the E2F1 expression was also upregulated in the Qiangjing tablets groups， with statistical significance in the medium-dose group （P<0.05）. The expression of E2F2 was downregulated in all the Qiangjing tablets groups. ConclusionQiangjing tablets delay the aging process of Leydig cells and testicular tissue by up-regulating the expression of CDK4 and lowering the levels of E2F1 and E2F2.

ObjectiveTo explore the mechanism by which Qiangjing tablets （QJT） alleviate the spermatogenic function damage caused by varicocele （VC） based on the Kelch-like ECH-associated protein 1 （Keap1）/nuclear factor erythroid 2-related factor 2 （Nrf2） signaling pathway-mediated oxidative stress. MethodsTen Sprague-Dawley （SD） rats were randomly assigned into a control group and a model group. Pathological examination confirmed the stability of the model. Thirty-six SD rats were randomized into control， model， low-dose （0.23 g·kg^-1） QJT， medium-dose （0.46 g·kg^-1） QJT， high-dose （0.92 g·kg^-1） QJT， and mazhilin （61.7 mg·kg^-1） groups， with 6 rats in each group. A rat model of experimental left varicocele （ELV） was established by partially ligating the left renal vein to simulate the human nutcracker syndrome. The rats were administrated with corresponding agents once a day for 28 consecutive days. The in vitro testicular culture model of rats was established through the Transwell chamber method and intervened with QJT-containing sera （2.3， 4.6， and 9.2 g·kg^-1）. Microscopic observation was carried out for the morphology of the left kidney. A micrometer was used to measure the diameter of the left spermatic vein （LSV）. The body weights of rats were recorded weekly， and the epididymis and testis weights were measured. The pathological changes of the testicular tissue was observed via hematoxylin-eosin （HE） staining. The levels of testosterone （T） in the cell culture supernatant and reactive oxygen species （ROS） in the rat testicular tissue were measured by enzyme-linked immunosorbent assay （ELISA）. Flow cytometry was employed to determine the ROS content. Immunohistochemical staining was conducted to analyze Keap1， Nrf2， 3β-hydroxysteroid dehydrogenase （3β-Hsd）， GATA-binding protein-4 （Gata-4）， and proto-oncogene receptor tyrosine kinase （C-kit）. The ultrastructure of the tissue was observed by transmission electron microscopy （TEM）. Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling （TUNEL） staining. The expression of Keap1， Nrf2， glutathione S-transferase α2 （Gsta2）， glutathione S-transferase μ1 （Gstm1）， heme oxygenase-1 （HO-1）， quinone oxidoreductase 1 （Nqo1）， and thioredoxin reductase 1 （Txnrd1） was quantified by Real-time quantitative polymerase chain reaction（Real-time PCR） and Western blot. ResultsCompared with the control group， the ROS content and the percentage of apoptotic cells in the model group were significantly increased （P<0.01）， the T concentration was significantly decreased （P<0.01）， the mRNA and protein expressions of Keap1 were significantly increased （P<0.01）， and the mRNA and protein expressions of Nrf2， Gsta2， Gstm1， HO-1， Nqo1 and Txnrd1 were significantly decreased （P<0.05）. Compared with the model group， the ROS content and the percentage of apoptotic cells in each dose group of the Qiangjing Tablets were significantly reduced （P<0.05）， and the mRNA and protein expressions of Keap1 were significantly decreased （P<0.05）， while the mRNA and protein expressions of Nrf2， Gsta2， Gstm1， HO-1， Nqo1 and Txnrd1 were significantly increased （P<0.05）. ConclusionQJT improves sperm motility in the rat model of VC by modulating the Keap1/Nrf2 signaling pathway and reducing oxidative stress injury.