BACKGROUND:Rev-erbα is involved in the regulation of inflammation,but pharmacological activation of Rev-erbα increases the risk for cardiovascular diseases.To reduce the relevant risk,an exploration on SR9009,a Rev-erbα agonist,combined with other drugs to relieve inflammation in skeletal myoblasts was conducted,laying the theoretical foundation for the treatment of inflammation-associated skeletal muscle atrophy. OBJECTIVE:To investigate the relationship of SR9009,indolepropionic acid and nuclear factor-κB signaling pathways in lipopolysaccharide-induced C2C12 myoblasts. METHODS:(1)C2C12 myoblasts were induced to differentiate in the presence of lipopolysaccharide(1 μg/mL).RNA-seq and KEGG pathway analysis were used to study signaling pathways.(2)C2C12 myoblast viability was assessed using the cell counting kit-8 assay to determine optimal concentrations of indolepropionic acid.Subsequently,cells were categorized into control group,lipopolysaccharide(1 μg/mL)group,SR9009(10 μmol/L)+lipopolysaccharide group,indolepropionic acid(80μmol/L)+lipopolysaccharide group,and SR9009+indolepropionic acid+lipopolysaccharide group.ELISA was employed to measure protein expression levels of interleukin-6 in the cultured supernatant.Real-time quantitative PCR were employed to measure mRNA expression levels of interleukin-6,tumor necrosis factor α,TLR4 and CD14.Western blot assay were employed to measure protein expression levels of NF-κB p65 and p-NF-κB p65.(3)After Rev-erbα was knocked down by siRNA,knockdown efficiency was assessed by RT-qPCR.And mRNA levels of interleukin-6 and tumor necrosis factor α were also measured. RESULTS AND CONCLUSION:Compared with the blank control group,lipopolysaccharide time-dependently inhibited myofibroblast fusion to form myotubes,the mRNA expression levels of interleukin-6 and tumor necrosis factor α were elevated,and the level of interleukin-6 in the cell supernatant was significantly increased.The results of KEGG pathway showed that the nuclear factor-κB signaling pathway was activated by lipopolysaccharide.Indolepropionic acid exhibited significant suppression of C2C12 myoblasts viability when its concentration exceeded 80 μmol/L.Indolepropionic acid and SR9009 inhibited the activation of NF-κB signaling pathway,thereby played an anti-inflammatory role,and suppressed the mRNA expression levels of interleukin-6,tumor necrosis factor α,TLR4 and CD14.Compared with the lipopolysaccharide group,the ratio of p-NF-κB p65/NF-κB p65 protein expression were downregulated.SR9009 combined with indolepropionic acid notably reduced lipopolysaccharide-induced inflammation,further downregulated the mRNA expression levels of interleukin-6,tumor necrosis factor α,TLR4 and CD14.The ratio of p-NF-κB p65/NF-κB p65 protein expression was significantly lower than that in the SR9009+lipopolysaccharide group or indolepropionic acid+lipopolysaccharide group.Rev-erbα increases time-dependently with lipopolysaccharide induction.The knockdown efficiency of Rev-erbα by siRNA reached over 58%,and lipopolysaccharide was added after Rev-erbα was successfully knocked down.Compared with the lipopolysaccharide group,the mRNA expression levels of interleukin-6 and tumor necrosis factor α were significantly up-regulated.These results conclude that Rev-erbα may act as a promising pharmacological target to reduce inflammation.SR9009 targeted activation of Rev-erbα combined with indolepropionic acid significantly inhibits the nuclear factor-κB signaling pathway and attenuates the inflammatory response of C2C12 myofibroblasts.Moreover,the combined anti-inflammatory effect is superior to that of the intervention alone.

Breast cancer is the most prevalent malignant tumor that poses a threat to women's health in China,with incidence and mortality rates persistently increasing.Given this critical situation,there is an urgent need to optimize therapeutic options through basic translational research to address current treatment challenges.This article provided a comprehensive overview of the significant advancements in fundamental translational breast cancer research in China over the past five years,aiming to provide a scientific basis and new directions for precision treatment of breast cancer.This research encompasses a range of subjects,including molecular typing,biomarker identification,exploration of drug resistance mechanisms,optimization of precision treatment strategies,and identification of new targets in breast cancer.In the domain of molecular typing,researchers have revealed substantial disparities in treatment responses among distinct subtypes of breast cancer through in-depth analysis.This has led to the proposal of specific therapeutic strategies for each subtype,thereby establishing a robust theoretical foundation for individualized treatment approaches.The identification of biomarkers plays a pivotal role in selecting appropriate treatment options for patients.Recent research advancements have demonstrated the potential of liquid biopsy and proteomics technologies in uncovering promising biomarkers,offering novel prospects for the early diagnosis and prognostic assessment of breast cancer.In the investigation of resistance mechanisms,researchers have elucidated the molecular underpinnings of resistance to endocrine therapy and human epidermal growth factor receptor 2(HER2)-targeted therapy and proposed potential strategies to overcome resistance.This has paved the way for novel approaches to enhance therapeutic efficacy.In the context of immunotherapy and targeted therapies,the discernment of novel targets and biomarkers has facilitated novel perspectives on breast cancer treatment.Based on advanced comprehension of tumor heterogeneity,researchers constantly optimize precision treatment strategies through multiomics analysis,thus offering patients with breast cancer enhanced personalized treatment options.Concurrently,the implementation of novel technologies has been instrumental in facilitating the advancement of precision treatment for breast cancer.For instance,the application of artificial intelligence technology has demonstrated considerable potential in the early screening,diagnosis,efficacy assessment and prognosis prediction of breast cancer.Conversely,the advent of innovative drug delivery systems facilitated by nanotechnology has led to enhanced targeting and efficacy of pharmaceutical agents.Furthermore,research into hydrogel patch technology and tumor vaccines has yielded novel strategies for the treatment of breast cancer.Overall,China has accomplished remarkable achievements in the field of basic translational research on breast cancer.These findings not only enhance our understanding of the molecular mechanisms of breast cancer,but also provide new directions and hope for the development of future therapeutic strategies.With the advancement of multidisciplinary integration and the application of new emerging technologies,precision therapy is expected to provide more benefits to breast cancer patients.

Objective To investigate the effect and mechanism of miR-155-5p targeting suppressor of cytokine signaling 1(SOCS1)in regulating the Janus kinase 2(JAK2)/signal transducer and activator of transcrip-tion 3(STAT3)signaling pathway in renal injury associated with lupus nephritis(LN).Methods Thirty female MRL-faslpr lupus model mice were randomly divided into five groups(n=6 per group):the model group,the antagomir NC group,the miR-155-5p antagomir group,the miR-155-5p antagomir+shRNA control group,and the miR-155-5p antagomir+SOCS1 shRNA group.The mice were treated with adeno-associated virus vectors carrying miR-155-5p antagomir,antagomir NC,SOCS1 shRNA,or shRNA control.Additionally,six age-matched C57BL/6 mice served as a control group and received an equivalent volume of saline.Serum blood urea nitrogen(BUN)and creatinine(Scr)levels,renal histopathological changes,and the expression levels of miR-155-5p,SOCS1,phosphorylated JAK2(p-JAK2),and phosphorylated STAT3(p-STAT3)in renal tissues were evaluated.Results Compared with the normal group,the model group exhibited significantly elevated levels of BUN,Scr,miR-155-5p,p-JAK2,and p-STAT3 proteins in the kidneys(P<0.01),while the expression level of SOCS1 was markedly reduced(P<0.01).Compared with both the model group and the antagomir NC group,the miR-155-5p antagomir group showed decreased levels of BUN,Scr,miR-155-5p,p-JAK2,and p-STAT3 proteins(P<0.01),along with a significant increase in SOCS1 expression(P<0.01).Similarly,compared with the miR-155-5p antagomir group and the miR-155-5p antagomir+shRNA control group,the miR-155-5p antagomir+SOCS1 shRNA group demon-strated significantly higher levels of BUN,Scr,miR-155-5p,p-JAK2,and p-STAT3 proteins(P<0.01),while SOCS1 expression was notably decreased(P<0.01).Renal pathology analysis revealed that,compared to the normal group,the model group exhibited glomerular atrophy,extensive infiltration of inflammatory cells in the renal tubulointerstitial region,and partial renal tubular necrosis.In contrast,the miR-155-5p antagomir group showed marked improvements in glomerular atrophy,tubular necrosis,and inflammatory cell infiltration compared with the model group and antagomir NC group.Furthermore,compared with the miR-155-5p antagomir group and the miR-155-5p antagomir+shRNA control group,the miR-155-5p antagomir+SOCS1 shRNA group exhibited more severe glomerular atrophy,tubular necrosis,and inflammatory cell infiltration.Conclusion MiR-155-5p exacerbates renal damage in MRL-faslpr lupus model mice by targeting SOCS1,potentially through the activation of the JAK2/STAT3 signaling pathway.

Breast cancer is the most prevalent malignant tumor that poses a threat to women's health in China,with incidence and mortality rates persistently increasing.Given this critical situation,there is an urgent need to optimize therapeutic options through basic translational research to address current treatment challenges.This article provided a comprehensive overview of the significant advancements in fundamental translational breast cancer research in China over the past five years,aiming to provide a scientific basis and new directions for precision treatment of breast cancer.This research encompasses a range of subjects,including molecular typing,biomarker identification,exploration of drug resistance mechanisms,optimization of precision treatment strategies,and identification of new targets in breast cancer.In the domain of molecular typing,researchers have revealed substantial disparities in treatment responses among distinct subtypes of breast cancer through in-depth analysis.This has led to the proposal of specific therapeutic strategies for each subtype,thereby establishing a robust theoretical foundation for individualized treatment approaches.The identification of biomarkers plays a pivotal role in selecting appropriate treatment options for patients.Recent research advancements have demonstrated the potential of liquid biopsy and proteomics technologies in uncovering promising biomarkers,offering novel prospects for the early diagnosis and prognostic assessment of breast cancer.In the investigation of resistance mechanisms,researchers have elucidated the molecular underpinnings of resistance to endocrine therapy and human epidermal growth factor receptor 2(HER2)-targeted therapy and proposed potential strategies to overcome resistance.This has paved the way for novel approaches to enhance therapeutic efficacy.In the context of immunotherapy and targeted therapies,the discernment of novel targets and biomarkers has facilitated novel perspectives on breast cancer treatment.Based on advanced comprehension of tumor heterogeneity,researchers constantly optimize precision treatment strategies through multiomics analysis,thus offering patients with breast cancer enhanced personalized treatment options.Concurrently,the implementation of novel technologies has been instrumental in facilitating the advancement of precision treatment for breast cancer.For instance,the application of artificial intelligence technology has demonstrated considerable potential in the early screening,diagnosis,efficacy assessment and prognosis prediction of breast cancer.Conversely,the advent of innovative drug delivery systems facilitated by nanotechnology has led to enhanced targeting and efficacy of pharmaceutical agents.Furthermore,research into hydrogel patch technology and tumor vaccines has yielded novel strategies for the treatment of breast cancer.Overall,China has accomplished remarkable achievements in the field of basic translational research on breast cancer.These findings not only enhance our understanding of the molecular mechanisms of breast cancer,but also provide new directions and hope for the development of future therapeutic strategies.With the advancement of multidisciplinary integration and the application of new emerging technologies,precision therapy is expected to provide more benefits to breast cancer patients.

Objective To investigate the effect and mechanism of miR-155-5p targeting suppressor of cytokine signaling 1(SOCS1)in regulating the Janus kinase 2(JAK2)/signal transducer and activator of transcrip-tion 3(STAT3)signaling pathway in renal injury associated with lupus nephritis(LN).Methods Thirty female MRL-faslpr lupus model mice were randomly divided into five groups(n=6 per group):the model group,the antagomir NC group,the miR-155-5p antagomir group,the miR-155-5p antagomir+shRNA control group,and the miR-155-5p antagomir+SOCS1 shRNA group.The mice were treated with adeno-associated virus vectors carrying miR-155-5p antagomir,antagomir NC,SOCS1 shRNA,or shRNA control.Additionally,six age-matched C57BL/6 mice served as a control group and received an equivalent volume of saline.Serum blood urea nitrogen(BUN)and creatinine(Scr)levels,renal histopathological changes,and the expression levels of miR-155-5p,SOCS1,phosphorylated JAK2(p-JAK2),and phosphorylated STAT3(p-STAT3)in renal tissues were evaluated.Results Compared with the normal group,the model group exhibited significantly elevated levels of BUN,Scr,miR-155-5p,p-JAK2,and p-STAT3 proteins in the kidneys(P<0.01),while the expression level of SOCS1 was markedly reduced(P<0.01).Compared with both the model group and the antagomir NC group,the miR-155-5p antagomir group showed decreased levels of BUN,Scr,miR-155-5p,p-JAK2,and p-STAT3 proteins(P<0.01),along with a significant increase in SOCS1 expression(P<0.01).Similarly,compared with the miR-155-5p antagomir group and the miR-155-5p antagomir+shRNA control group,the miR-155-5p antagomir+SOCS1 shRNA group demon-strated significantly higher levels of BUN,Scr,miR-155-5p,p-JAK2,and p-STAT3 proteins(P<0.01),while SOCS1 expression was notably decreased(P<0.01).Renal pathology analysis revealed that,compared to the normal group,the model group exhibited glomerular atrophy,extensive infiltration of inflammatory cells in the renal tubulointerstitial region,and partial renal tubular necrosis.In contrast,the miR-155-5p antagomir group showed marked improvements in glomerular atrophy,tubular necrosis,and inflammatory cell infiltration compared with the model group and antagomir NC group.Furthermore,compared with the miR-155-5p antagomir group and the miR-155-5p antagomir+shRNA control group,the miR-155-5p antagomir+SOCS1 shRNA group exhibited more severe glomerular atrophy,tubular necrosis,and inflammatory cell infiltration.Conclusion MiR-155-5p exacerbates renal damage in MRL-faslpr lupus model mice by targeting SOCS1,potentially through the activation of the JAK2/STAT3 signaling pathway.

Breast cancer is the most common malignant tumor among women worldwide,with incidence rates rising annually.The treatment of breast cancer has undergone significant transformations,evolving from an initial reliance on a single surgical approach to the incorporation of systemic therapy,and more recently,to subtype-specific therapy.Clinically,breast cancer is classified into luminal,HER2-positive,and triple-negative breast cancer(TNBC)based on the expression of hormone receptor(HR)and human epidermal growth factor receptor 2(HER2),with corresponding treatments including endocrine therapy,anti-HER2 targeted therapy,and chemotherapy.However,the current subtype-based treatment strategies lack personalization,with approximately 30%of patients still facing resistance and relapse.While the overall survival rate of patients with HER2-positive breast cancer has been steadily increasing,significant survival improvements have not been observed in patients with triple-negative and luminal breast cancer.To overcome the clinical bottleneck of"incomplete classification and imprecise treatment",the concept of"subtype-precise"therapy has emerged.This innovative approach involves further subclassification of existing subtypes to identify specific targets for precision treatment,characterized by broad population coverage and high specificity.Over the past decade,the multidisciplinary team at Fudan University Shanghai Cancer Center has established a comprehensive molecular portrait of Chinese Breast Cancer Genome Atlas(CBCGA).They deeply analyzed the molecular characteristics of TNBC,leading to the development of a"Fudan subtype"closely related to clinical outcomes:luminal androgen receptor subtype(LAR),which can be targeted with anti-HER2 and CDK4/6 inhibitors;the immunomodulatory subtype(IM),suitable for immunotherapy;basal-like immune-suppressed subtype(BLIS),which can be treated with platinum-based drugs or poly(ADP-ribose)polymerase(PARP)inhibitors;and mesenchymal-like subtype(MES),which can be treated with anti-cancer stem cell and anti-angiogenic therapies.The team then extended the concept of"subtype-precise"to luminal breast cancer,the subtype with the largest number,the highest proportion and the risk of recurrence for decades.They divided it into four molecular subtypes and proposing corresponding precision treatment strategies:canonical luminal subtype(SNF1),sensitive to endocrine therapy;immunogenic subtype(SNF2),amenable to immunotherapy;proliferative subtype(SNF3),treatable by CDK4/6 inhibitors;and receptor tyrosine kinase-driven subtype(SNF4),targetable with tyrosine kinase inhibitors.The team is currently conducting phase Ⅲ randomized controlled trials to further validate the"subtype-precise"therapy and promote the"subtype-precise"Fudan experience to enhance overall breast cancer treatment efficacy.Looking forward,the integration of emerging diagnostic tools,such as artificial intelligence,coupled with the continuous update of subtype-specific targets and targeted therapies,is expected to further refine and expand"subtype-precise"therapy.This approach holds great promises for enhancing patient prognosis and leading a new revolution in breast cancer treatment.

Objective To monitor the antifungal resistance of clinical isolates of Candida spp.in the East China region.Methods MALDI-TOF MS or molecular methods were used to re-identify the strains collected from January 2018 to December 2022.Antifungal susceptibility testing was performed using the broth microdilution method.The susceptibility test results were interpreted according to the breakpoints of 2022 Clinical and Laboratory Standards Institute(CLSI)documents M27 M44s-Ed3 and M57s-Ed4.Results A total of 3 026 strains of Candida were collected,65.33％of which were isolated from sterile body sites,mainly from blood(38.86％)and pleural effusion/ascites(10.21％).The predominant species of Candida were Candida albicans(44.51％),followed by Candida parapsilosis complex(19.46％),Candida tropicalis(13.98％),Candida glabrata(10.34％),and other Candida species(0.79％).Candida albicans showed overall high susceptibility rates to the 10 antifungal drugs tested(the lowest rate being 93.62％).Only 2.97％of the strains showed dose-dependent susceptibility(SDD)to fluconazole.Candida parapsilosis complex had a SDD rate of 2.61％and a resistance rate of 9.42％to fluconazole,and susceptibility rates above 90％to other drugs.Candida glabrata had a SDD rate of 92.01％and a resistance rate of 7.99％to fluconazole,resistance rates of 32.27％and 48.24％to posaconazole and voriconazole non-wild-type strains(NWT),respectively,and susceptibility rates above 90％to other drugs.Candida tropicalis had resistance rates of 29.55％and 26.24％to fluconazole and voriconazole,respectively,resistance rates of 76.60％and 21.99％to posaconazole and echinocandins non-wild-type strains(NWT),and a resistance rate of 2.36％to echinocandins.Conclusions The prevalence and species distribution of Candida spp.in the East China region are consistent with previous domestic and international reports.Candida glabrata exhibits certain degree of resistance to fluconazole,while Candida tropicalis demonstrates higher resistance to triazole drugs.Additionally,echinocandins resistance has emerged in Candida albicans,Candida glabrata,Candida tropicalis,and Candida parapsilosis.

Objective This study established a model of invasive Aspergillus niger lung disease in immunosuppressed rats to provide theoretical support for the pharmacodynamic evaluation of anti-invasive pulmonary aspergillosis drugs and mechanism studies.Methods Sixty SD rats were randomly divided into a normal control group;cyclophosphamide control group,and cyclophosphamide+fungal infection low,medium,and high dose groups,with 12 animals in each group.General clinical observations were performed daily,and the serum levels of immunoglobulin(Ig)G and IgM and galactomannan(GM)were detected by ELISA on the 3rd and 7th days of modeling.Simultaneously,the ratio of CD4+and CD8+cells,content of white blood cells(WBCs)and neutrophils(Neu)in peripheral blood,the Aspergillus niger load in alveolar lavage,and morphological changes to rat lung tissue were observed.Results Rats in the cyclophosphamide control and cyclophosphamide+fungal infection groups showed reduced voluntary activity and erect hair after modeling,and rats in the cyclophosphamide+fungal infection group also had shortness of breath and audible wet rhonchi in the lungs.Compared with the normal control group,rats in the cyclophosphamide control group showed significant reductions in the levels of CD4+,WBC,Neu,IgG,and IgM in the blood,and their proportion of CD8+cells was significantly higher(P＜0.05,P＜0.01).Compared with the cyclophosphamide control group,rats in the cyclophosphamide+fungal infection medium-and high-dose groups had significantly reduced blood levels of IgG,IgM,and CD4+cells(P＜0.05,P＜0.01);while the cyclophosphamide+fungal infection low-,medium-,and high-dose groups had significantly reduced blood levels of WBC and Neu(P＜0.05,P＜0.01).Additionally,rats in the cyclophosphamide+fungal infection medium-and high-dose groups had significantly increased blood CD8+cells(P＜0.05,P＜0.01),Blood GM levels and the alveolar lavage Aspergillus niger load were significantly increased in rats in the cyclophosphamide+fungal infection low-,medium-,and high-dose groups compared with the cyclophosphamide control group(P＜0.05,P＜0.01).The lung tissues of the cyclophosphamide+fungal infection low-,medium-,and high-dose groups showed mycelial distribution and destruction of alveolar epithelium,increase of bronchial epithelial cup cells in the alveoli,and infiltration of inflammatory cells,and the degree of lesions was positively correlated with the modeling dose.Conclusions In this study,we used Aspergillus niger combined with cyclophosphamide immunosuppressant to construct a model of invasive Aspergillus niger lung disease.The duration of the disease was positively correlated with the concentration of bacterial fluid and modeling time,confirming that cellular immunity plays an important role in the pathogenesis of the disease.At the same time,Ig can also affect the development of invasive pulmonary aspergillosis,and it is speculated that the pathogenesis may be related to the level of Ig produced by humoral immunity.

Objective Taking Sortilin as the entry point,this study aims to explore the mechanism of vascular calcification in chronic renal failure(CRF)and explore the influence of Sanqi on Sortilin,TLRs and vascular calcification,and to provide an effective method for clinical reduction of cardiovascular events in CRF.Methods Thirty-six male SD rats were randomly divided into normal group,model group,low-,medium-and high-dose Sanqi group and calcitriol group,with 6 rats in each.The replicative CRF vascular calcification rat model was fed with adenine combined with high phosphorus diet.Aortic calcium salt deposition,serum creatinine(Scr),urea nitrogen(BUN),blood calcium(Ca),blood phosphorus(P),total cholesterol(TC),triglyceride(TG),TLRs and Sortilin protein in aorta and inflammatory factors were detected.Results In the model group,renal fibrosis was obvious and many adenine crystals were found in renal interstitium.Large deposits of calcium salts were found.Renal fibrosis and calcium salt deposition were alleviated in different degrees in all treatment groups.Compared with those in the normal group,the level of BUN,Cr,P,TG,TC,IFN-γ,IL-6,IL-10 and IL-17A in the serum of the model group was ascended(P<0.01),while the level of Ca was descended(P<0.01).Compared with those in the model group,the level of BUN,Cr,P,TG,TC,IFN-γ,IL-6,IL-10 and IL-17A in the serum of rats in the Sanqi medium and high dose group and calcitriol group was significantly decreased(P<0.01),and the contents of Ca were significantly increased(P<0.05 or P<0.01).Compared with those in the normal group,the protein expression of BMP2,RUNX2,Sortilin,TLR7 and TLR9 in aortic tissue of rats in the model group was elevated(P<0.01),while the protein expression of SM22α was declined(P<0.01).Compared with those in the model group,the protein expression of BMP2,RUNX2,Sortilin,TLR7,and TLR9 in the low-,medium-,and high-dose Sanqi group and calcitriol group was decreased significantly(P<0.01);the protein expression of SM22α was increased significantly(P<0.05 or P<0.01),and the high-dose Sanqi group and calcitriol group had more significant effects.Conclusion Sanqi can improve renal fibrosis and vascular calcification in CRF model rats,and its mechanism may be related to the regulation of biological functions of Sortilin and TLRs.

BACKGROUND:Some studies have found that local application of alendronate can promote osteogenesis,but less is reported on the process of distraction osteogenesis. OBJECTIVE:To observe the promoting effect of alendronate on rapid mandibular distraction in a rabbit model and explore its possible mechanism. METHODS:Thirty-six male New Zealand white rabbits were randomly divided into groups A,B and C(n=12 per group)after operation and rapid distraction(3-day delay period followed by 3-day distraction at 1.5 mm/12 hours).At the 1st,3rd and 7th days of the consolidation period,animal were injected with 200 μg/kg alendronate in group A and 100 μg/kg alendronate in group B,while those in group C were treated as controls.CT scanning and dual energy X-ray bone mineral density measurement were performed at 4 and 8 weeks of the consolidation period.After the radionuclide scanning was completed at the 4th week,several animals were sacrificed and the samples were collected for western blot assay and tartrate resistant acid phosphatase staining.A three-point bending test was performed after the animals were sacrificed at the 8th week. RESULTS AND CONCLUSION:CT results showed that bone formation in the distraction space of group B was significantly better than that in groups A and C.At the 4th week,the bone mineral density in group B was(0.092±0.010)g/cm2,which was 1.26 times higher than that in group A(P＜0.001)and 1.28 times higher than that in group C(P＜0.001).At the 8th week,the bone mineral density in group B was(0.175±0.029)g/cm2,which was 1.38 times higher than that in group A(P＜0.001)and 1.45 times higher than that in group C(P＜0.001).Tartrate resistant acid phosphatase staining showed that the number of osteoclast-like cells in group C were 2.83 times more than that in group A(P＜0.001)and 2.21 times more than that in group B(P＜0.001).The radionuclide intensity was higher in group C than in groups A and B.Western blot assay results showed that the expression of Runx2 was significantly stronger in group B than in groups A and C.The maximum biomechanical load in group B was(158.48±23.21)N,which was 1.26 times higher than that in group A(P=0.007)and 1.31 times higher than that in group C(P=0.003).To conclude,the low concentration of alendronate may promote rapid distraction osteogenesis of the rabbit mandible by inhibiting osteoclast signals.