1.The Histone Methyltransferase EZH2 is Downregulated in the Terminal Differentiation of Cardiomyocytes
Wan-Yi ZHANG ; Wan-Lei ZHANG ; Yuan-Yuan LIU ; Ling-Er DING ; Qi-Kai TANG ; Zhen-Hang LI ; Hao-Ying YANG ; Tao LI
Chinese Journal of Biochemistry and Molecular Biology 2025;41(3):415-425
Enhancer of zeste homolog 2(EZH2)is a histone methyltransferase It mediates trimethylation of lysine 27 on histone H3,thereby facilitating the epigenetic silencing of downstream genes.In conjunc-tion with SUZ12,EED,and other components,it constitutes the polycomb repressive complex 2(PRC2)complex.While EZH2 is intricately involved in cellular proliferation and cardiac development,the chan-ges in its expression during cardiac terminal differentiation remain elusive.In this study,we employed differential gene expression analysis of embryonic and adult myocardial cells using the GEO database,and found that EZH2 is highly expressed in embryonic myocardium,but is present at very low levels in adult myocardium(P<0.0001).Conversely,the expression changes of PRC2 members SUZ12 and EED are not as pronounced.Online analysis through the Tabula Muris database indicates that under physiological conditions,various cell subpopulations in the adult mouse heart exhibit negligible expression of EZH2.Immunohistochemical staining of mouse cardiac tissues shows that EZH2 is highly expressed in embryonic and neonatal myocardium but declines progressively from the first day after birth(P<0.0001),becoming almost undetectable by the third day.Western blotting further confirms the rapid disappearance of EZH2 expression post-birth(P<0.05),with EZH1 compensating for the downregulation of EZH2 to maintain H3K27me3 modification levels.Additionally,using the P19 teratocarcinoma stem cell model for cardio-myocyte differentiation,it is observed that EZH2 is significantly upregulated during the transition from cardiac progenitor cells to spontaneously beating cardiomyocytes,correlating with the expression of the cardiomyocyte transcription factor Gata4(P<0.01).Targeted degradation of EZH2 using the small mole-cule drug MS1943 significantly inhibits the proliferation of induced cardiomyocytes,as evidenced by 5-e-thynyl-2'-deoxyuridine(EdU)incorporation assays(P<0.01),and RT-qPCR reveals a marked in-crease in the expression of the proliferation inhibitor CDKN1A(P<0.01).In summary,the high expres-sion of EZH2 in embryonic myocardial cells is associated with enhanced cell proliferation.The rapid loss of EZH2 expression postnatally correlates with the loss of proliferative capacity in cardiomyocytes,mark-ing it as a key indicator of cardiac terminal differentiation.
2.The Histone Methyltransferase EZH2 is Downregulated in the Terminal Differentiation of Cardiomyocytes
Wan-Yi ZHANG ; Wan-Lei ZHANG ; Yuan-Yuan LIU ; Ling-Er DING ; Qi-Kai TANG ; Zhen-Hang LI ; Hao-Ying YANG ; Tao LI
Chinese Journal of Biochemistry and Molecular Biology 2025;41(3):415-425
Enhancer of zeste homolog 2(EZH2)is a histone methyltransferase It mediates trimethylation of lysine 27 on histone H3,thereby facilitating the epigenetic silencing of downstream genes.In conjunc-tion with SUZ12,EED,and other components,it constitutes the polycomb repressive complex 2(PRC2)complex.While EZH2 is intricately involved in cellular proliferation and cardiac development,the chan-ges in its expression during cardiac terminal differentiation remain elusive.In this study,we employed differential gene expression analysis of embryonic and adult myocardial cells using the GEO database,and found that EZH2 is highly expressed in embryonic myocardium,but is present at very low levels in adult myocardium(P<0.0001).Conversely,the expression changes of PRC2 members SUZ12 and EED are not as pronounced.Online analysis through the Tabula Muris database indicates that under physiological conditions,various cell subpopulations in the adult mouse heart exhibit negligible expression of EZH2.Immunohistochemical staining of mouse cardiac tissues shows that EZH2 is highly expressed in embryonic and neonatal myocardium but declines progressively from the first day after birth(P<0.0001),becoming almost undetectable by the third day.Western blotting further confirms the rapid disappearance of EZH2 expression post-birth(P<0.05),with EZH1 compensating for the downregulation of EZH2 to maintain H3K27me3 modification levels.Additionally,using the P19 teratocarcinoma stem cell model for cardio-myocyte differentiation,it is observed that EZH2 is significantly upregulated during the transition from cardiac progenitor cells to spontaneously beating cardiomyocytes,correlating with the expression of the cardiomyocyte transcription factor Gata4(P<0.01).Targeted degradation of EZH2 using the small mole-cule drug MS1943 significantly inhibits the proliferation of induced cardiomyocytes,as evidenced by 5-e-thynyl-2'-deoxyuridine(EdU)incorporation assays(P<0.01),and RT-qPCR reveals a marked in-crease in the expression of the proliferation inhibitor CDKN1A(P<0.01).In summary,the high expres-sion of EZH2 in embryonic myocardial cells is associated with enhanced cell proliferation.The rapid loss of EZH2 expression postnatally correlates with the loss of proliferative capacity in cardiomyocytes,mark-ing it as a key indicator of cardiac terminal differentiation.
3.Experimental study on alternative method of local lymph node assay using bromodeoxyuridine with flow cytometry(LLNA:BrdU-FCM)for skin sensitization evaluation of cosmetics
Xiao-jun LYU ; Ju ZHANG ; Sen WU ; Xiao-ling XU ; Meng-ting SHI ; Jin-jing XU ; Wang-ping PAN ; Jia-te SHEN ; Kai-yong HE
Chinese Pharmacological Bulletin 2025;41(4):793-799
Aim To establish and evaluate an alternative meth-od for detecting skin sensitization of cosmetics based on local lymph node assay using bromodeoxyuridine(BrdU)with flow cytometry(FCM).Methods(1)25%hexyl cinnamic alde-hyde(HCA)was chosen as a positive control with an acetone:olive oil(4∶1,V/V,AOO)mixture as a vehicle control for the experiment.The dorsal sides of both ears of mice were treated with test solutions on day 1,day 2,and day 3.Brdu solution was injected inter-peritoneally on day 5.On day 6,the bilateral ears and mandibular lymph nodes were excised,and the number of Brdu positive cells was measured by flow cytometry.The stim-ulation index(SI)was calculated to identify whether it was ≥3,in order to establish the method of LLNA:Brdu-FCM.(2)BrdU-FCM test was conducted using a blind method with the fif-teen reference substances listed in OECD TG429 whose skin sensitization potentials were known.The test substances were dissolved in AOO,N,N-dimethylformamide(DMF)or dimeth-yl sulfoxide(DMSO)at three different concentrations.Tests were performed the same as above.SI and EC2.7 were calculat-ed to evaluate whether the test substance was categorized as a skin sensitizer.The reliability and accuracy of the method were validated by comparing the classification of test substances with that in OECD TG429.Results The SI for 25%HCA was 3.9,showing positive in the skin sensitization test.It demonstrated that the LLNA:Brdu-FCM test method was properly implemen-ted.Nine test substances(2,4-dinitrochlorobenzene,4-pheny-lenediamine,cobalt chloride,2-mercaptobenzothiazole,hexyl-cinnamaldehyde,eugenol,phenyl benzoate,cinnamic alcohol,imidazolidinyl urea)were positive,and six test substances(methyl methacrylate,chlorobenzene,isopropanol,lactic acid,methyl salicylate,salicylic acid)were negative.The method was evaluated with sensitivity of 90%,specificity of 100%,positive prediction rate of 100%,negative prediction rate of 83%,false positive rate of 0%,false negative rate of 17%and accuracy of 93%.The LLNA:BrdU-FCM assay could correctly categorize the test substances that were skin sensitizers or non-sensitizers.Conclusion The LLNA:BrdU-FCM assay appears to be a relia-ble predictor of skin sensitization protential of chemicals,and it is expected to an alternative method for identifying skin sensitization as a supplementary in safety evaluation of cosmetic ingredient.
4.Determination of 12 inorganic elements in phloroglucinol injection by ICP-MS
Ying SUN ; Kai HE ; Huan CHEN ; Ling MA ; Caiyu ZHANG
Drug Standards of China 2025;26(5):533-537
Objective:A method was first established for determination simultaneously of 12 elements including B,Al,Si,As,Cd,Hg,Pb,Co,Ni,V,Cu and Sb in phloroglucinol injection,and investigate the elemental impuri-ty content of commercially available phloroglucinol injection.Methods:Samples were digested with microwave-as-sisted acid and determined by inductively coupled plasma chromatography(ICP-MS).Results:This method has a good linear relationship.The average recovery rate was range from 88.9%-100.4%.The repeatability RSD were range from 0.6%-5.8%,and the precision RSD were between 0.4%-8.1%.The methodological validation meets the requirements.B,Al,Si,As,Cd,Co,Ni,V,Cu were detected to varying degrees in 9 batches of sam-ples,and there were significant differences in content among different enterprises.The sources of elemental impuri-ties were deeply explored in combination with the production process,medicinal property and pharmaceutical packa-ging material.Conclusion:The new established method has strong specificity,high accuracy,reliable results,and can be used as a quality evaluation method for elemental impurities in phloroglucinol injection.
5.Experimental study on alternative method of local lymph node assay using bromodeoxyuridine with flow cytometry(LLNA:BrdU-FCM)for skin sensitization evaluation of cosmetics
Xiao-jun LYU ; Ju ZHANG ; Sen WU ; Xiao-ling XU ; Meng-ting SHI ; Jin-jing XU ; Wang-ping PAN ; Jia-te SHEN ; Kai-yong HE
Chinese Pharmacological Bulletin 2025;41(4):793-799
Aim To establish and evaluate an alternative meth-od for detecting skin sensitization of cosmetics based on local lymph node assay using bromodeoxyuridine(BrdU)with flow cytometry(FCM).Methods(1)25%hexyl cinnamic alde-hyde(HCA)was chosen as a positive control with an acetone:olive oil(4∶1,V/V,AOO)mixture as a vehicle control for the experiment.The dorsal sides of both ears of mice were treated with test solutions on day 1,day 2,and day 3.Brdu solution was injected inter-peritoneally on day 5.On day 6,the bilateral ears and mandibular lymph nodes were excised,and the number of Brdu positive cells was measured by flow cytometry.The stim-ulation index(SI)was calculated to identify whether it was ≥3,in order to establish the method of LLNA:Brdu-FCM.(2)BrdU-FCM test was conducted using a blind method with the fif-teen reference substances listed in OECD TG429 whose skin sensitization potentials were known.The test substances were dissolved in AOO,N,N-dimethylformamide(DMF)or dimeth-yl sulfoxide(DMSO)at three different concentrations.Tests were performed the same as above.SI and EC2.7 were calculat-ed to evaluate whether the test substance was categorized as a skin sensitizer.The reliability and accuracy of the method were validated by comparing the classification of test substances with that in OECD TG429.Results The SI for 25%HCA was 3.9,showing positive in the skin sensitization test.It demonstrated that the LLNA:Brdu-FCM test method was properly implemen-ted.Nine test substances(2,4-dinitrochlorobenzene,4-pheny-lenediamine,cobalt chloride,2-mercaptobenzothiazole,hexyl-cinnamaldehyde,eugenol,phenyl benzoate,cinnamic alcohol,imidazolidinyl urea)were positive,and six test substances(methyl methacrylate,chlorobenzene,isopropanol,lactic acid,methyl salicylate,salicylic acid)were negative.The method was evaluated with sensitivity of 90%,specificity of 100%,positive prediction rate of 100%,negative prediction rate of 83%,false positive rate of 0%,false negative rate of 17%and accuracy of 93%.The LLNA:BrdU-FCM assay could correctly categorize the test substances that were skin sensitizers or non-sensitizers.Conclusion The LLNA:BrdU-FCM assay appears to be a relia-ble predictor of skin sensitization protential of chemicals,and it is expected to an alternative method for identifying skin sensitization as a supplementary in safety evaluation of cosmetic ingredient.
6.Determination of 12 inorganic elements in phloroglucinol injection by ICP-MS
Ying SUN ; Kai HE ; Huan CHEN ; Ling MA ; Caiyu ZHANG
Drug Standards of China 2025;26(5):533-537
Objective:A method was first established for determination simultaneously of 12 elements including B,Al,Si,As,Cd,Hg,Pb,Co,Ni,V,Cu and Sb in phloroglucinol injection,and investigate the elemental impuri-ty content of commercially available phloroglucinol injection.Methods:Samples were digested with microwave-as-sisted acid and determined by inductively coupled plasma chromatography(ICP-MS).Results:This method has a good linear relationship.The average recovery rate was range from 88.9%-100.4%.The repeatability RSD were range from 0.6%-5.8%,and the precision RSD were between 0.4%-8.1%.The methodological validation meets the requirements.B,Al,Si,As,Cd,Co,Ni,V,Cu were detected to varying degrees in 9 batches of sam-ples,and there were significant differences in content among different enterprises.The sources of elemental impuri-ties were deeply explored in combination with the production process,medicinal property and pharmaceutical packa-ging material.Conclusion:The new established method has strong specificity,high accuracy,reliable results,and can be used as a quality evaluation method for elemental impurities in phloroglucinol injection.
7.Clinical analysis of clavicle anatomical plate in the treatment of AllmanⅡC type of clavicle fracture.
Jian-Zhong GE ; Jin-Rui GU ; Peng XU ; Zhi-Ling ZHANG ; Kai WANG
China Journal of Orthopaedics and Traumatology 2025;38(7):711-715
OBJECTIVE:
To evaluate the clinical efficacy and safety of clavicular anatomical plate in the treatment of clavicular Allmanic fracture.
METHODS:
Between January 2016 and December 2022, 27 patients with Allman ⅡC distal clavicle fractures were treated with clavicular anatomical plate. There were 19 males and 8 females, aged from 16 to 69 years old, with an average of (39.74±12.71) years old. There were 15 patients on the left side and 12 patients on the right side. There were 15 patients with single clavicle fracture and 12 patients complicated with other parts of the body or organ injury. The broken ends of the fractures were fixed with clavicular anatomical plate, including common compression clavicular anatomical plate in 19 patients and locking clavicular anatomical plate in 8 patients. The operation time and hospitalization days were recorded. Visual analogue scales (VAS) were utilized to assess subjective pain levels both preoperatively and 3 days postoperatively. Postoperatively, patients were monitored at intervals of 1 to 3 months until X-ray films confirmed fracture healing. In accordance with the University of California, Los Angeles (UCLA) shoulder rating system, evaluations were conducted on postoperative pain alleviation, functional recovery, range of motion in forward flexion, strength in forward flexion, and patient satisfaction.
RESULTS:
All patients were followed up for a period ranging from 12 to 18 months with an average of (14.70±1.61) months, and all clavicular fractures achieved successful union. The wounds of 24 patients healed in one stage, and 3 patients developed bleeding and exudation, they were cured after dressing change. There were no complications such as infection, plate and screw fracture, vascular and nerve injury. The operation time was(67.56±11.01) min. Significant differences were observed in pain relief, functional improvement, range of motion for forward flexion, strength of forward flexion, patient satisfaction, and overall scores at preoperative, 3 months postoperatively, 6 months postoperatively, and at the final follow-up(P<0.001).
CONCLUSION
The utilization of clavicular anatomical plates for the management of Allman typeⅡC fractures can provide early and stable fixation without compromising the acromioclavicular joint, thereby enabling patients to commence early mobilization and ensuring optimal fracture healing.
Humans
;
Male
;
Female
;
Clavicle/surgery*
;
Adult
;
Bone Plates
;
Middle Aged
;
Fractures, Bone/physiopathology*
;
Adolescent
;
Aged
;
Fracture Fixation, Internal/instrumentation*
;
Young Adult
8.Lumbar Spondylolysis in Chinese Adults: Prevalence and Musculoskeletal Conditions.
Dong YAN ; Yan Dong LIU ; Ling WANG ; Kai LI ; Wen Shuang ZHANG ; Yi YUAN ; Jian GENG ; Kang Kang MA ; Feng Yun ZHOU ; Zi Tong CHENG ; Xiao Guang CHENG
Biomedical and Environmental Sciences 2025;38(5):598-606
OBJECTIVE:
To determine the prevalence of lumbar spondylolysis (LS) and the proportion of spondylolytic spondylolisthesis (SS) in China, and to evaluate the musculoskeletal status of patients with LS and SS.
METHODS:
Spine Computed Tomography (CT) images were collected from community populations aged 40 and above in a nationwide multi-center project. LS was diagnosed, and SS was graded by an experienced radiologist. Bone mineral density (BMD) and paraspinal muscle parameters were quantified based on CT images.
RESULTS:
One hundred and seventeen patients of a total of 3,317 individuals were diagnosed with LS, corresponding to a prevalence rate of 3.53%. 63 of the 1,214 males (5.18%) and 54 of the 2,103 females (2.57%) were diagnosed with LS. SS occurred in 64/121 vertebrae (52.89%). BMD was not associated with LS ( P = 0.341). The L5 extensor paraspinal muscle density was higher in the LS group than in the non-LS group. In the LS group, patients with SS had a smaller L5 paraspinal extensor muscle cross-sectional area than those without SS ( P = 0.003).
CONCLUSION
The prevalence of LS in Chinese adults was 3.53%, with prevalence rates of 5.18% in males and 2.57% in females. Patients with LS have higher muscle density, whereas those with SS have smaller muscle cross-sectional areas at the L5 level.
Humans
;
Male
;
Female
;
Middle Aged
;
China/epidemiology*
;
Prevalence
;
Adult
;
Lumbar Vertebrae/diagnostic imaging*
;
Spondylolysis/diagnostic imaging*
;
Aged
;
Bone Density
;
Tomography, X-Ray Computed
;
Aged, 80 and over
;
Spondylolisthesis/epidemiology*
;
East Asian People
10.Clinical Effects of Pomalidomide-Based Regimen in the Treatment of Relapsed and Refractory Multiple Myeloma.
Man YANG ; Yan HUANG ; Ling-Xiu ZHANG ; Guo-Qing LYU ; Lu-Yao ZHU ; Xian-Kai LIU ; Yan GUO
Journal of Experimental Hematology 2025;33(2):431-436
OBJECTIVE:
To study the clinical effects of pomalidomide-based regimen in the treatment of relapsed and refractory multiple myeloma (RRMM).
METHODS:
60 patients with RRMM in hematology department of the First Affiliated Hospital of Xinxiang Medical University from November 2020 to January 2023 were selected. Among them, 15 cases were treated with PDD regimen (pomalidomide + daratumumab + dexamethasone), and 45 cases were treated with PCD regimen (pomalidomide + cyclophosphamide + dexamethasone). The clinical effects were evaluated.
RESULTS:
The median number of treatment cycles for the entire cohort was 5 (2-11), with an overall response rate (ORR) of 75.0%. The ORR of patients treated with PDD regimen was 73.3%, while the ORR of patients treated with PCD regimen was 75.6%. The ORR of 46 patients with non high-risk cytogenetic abnormalities (non-HRCA) was 86.9%, significantly higher than the 35.7% of 14 patients with HRCA (χ2 =15.031, P < 0.05). The median PFS for all patients was 8.0(95%CI : 6.8-9.1) months and the median OS was 14.0 (95%CI : 11.3-16.7) months. Among patients treated with PDD regimen, the PFS and OS of patients with non-HRCA were significantly higher than those of patients with HRCA [PFS: 7.0(95%CI : 4.6-9.3) months vs 4.0(95%CI : 3.1-4.8) months, χ2 =5.120, P < 0.05; OS: not reached vs 6.0(95%CI : 1.1-10.9) months, χ2 =9.870, P < 0.05]. Among patients treated with PCD regimen, the PFS and OS of patients with non-HRCA were significantly higher than those of patients with HRCA [PFS: 9.0(95%CI : 6.2-11.8) months vs 6.0(95%CI : 5.4-6.6) months, χ2=14.396, P < 0.05; OS: not reached vs 11.0(95%CI : 6.4-15.6) months, χ2 =7.471, P < 0.05].
CONCLUSION
The pomalidomide-based regimen has a good clinical effect and safety in the treatment of RRMM.
Humans
;
Multiple Myeloma/drug therapy*
;
Thalidomide/administration & dosage*
;
Dexamethasone/therapeutic use*
;
Antineoplastic Combined Chemotherapy Protocols/therapeutic use*
;
Female
;
Male
;
Middle Aged
;
Recurrence
;
Aged
;
Cyclophosphamide/therapeutic use*
;
Treatment Outcome
;
Antibodies, Monoclonal

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