AIM:To investigate the effect of silent information regulator 1(SIRT1)on the degree of aging and apoptosis in a mouse cardiomyocyte aging model through the regulation of Wnt/β-catenin pathway.METHODS:An in vi-tro aging model was established by inducing HL-1 cells with 40 μmol/L D-galactose(D-Gal).The HL-1 cells were trans-fected with a lentivirus overexpressing SIRT1,and the transfection efficiency was verified by Western blot.Western blot was used to detect the protein expression levels of SIRT1,P53,P21,cleaved caspase-3,B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),β-catenin,Wnt3a and c-Myc.Senescence-associated β-galactosidase(SA-β-Gal)staining was used to detect cellular senescence level.MTT colorimetric assay was used to detect the cell viability,and flow cytometry was used to detect the apoptosis.RESULTS:Treatment of HL-1 mouse cardiomyocytes with D-Gal led to in-creases in the expression levels of aging-related proteins P53 and P21,as well as an increase in SIRT1 protein level.Addi-tionally,the SA-β-Gal staining showed a significant increase in the positive area(P＜0.05).The expression levels of apop-tosis-related proteins cleaved caspase-3 and Bax were elevated,while the level of the anti-apoptotic protein Bcl-2 was re-duced(P＜0.05).There was a marked decrease in cell viability(P＜0.05),and flow cytometry analysis demonstrated a significant increase in cell apoptosis rate(P＜0.05),which was positively correlated with the duration of D-Gal treatment.Overexpression of SIRT1 notably reduced both aging and apoptosis levels after 48 h of D-Gal treatment(P＜0.05).After D-Gal treatment,the expression levels of β-catenin,c-Myc and Wnt3a proteins were up-regulated.However,these levels were reduced when SIRT1 was overexpressed.Moreover,the addition of LiCl,a Wnt/β-catenin pathway agonist,resulted in increased expression levels of β-catenin,c-Myc and Wnt3a proteins compared with the group with SIRT1 overexpres-sion and D-Gal treatment(P＜0.05).CONCLUSION:SIRT1 inhibits cardiomyocyte apoptosis and alleviates cardiomyo-cyte aging through the Wnt/β-catenin pathway.

Objective:To design and evaluate a cell membrane vaccine strategy based on dendritic cell membrane microbubbles(DCM@MBs),and to explore its potential application in tumor immunotherapy,especially the immune-specific killing of tumor cells through the activation of T cells.Methods:At first,tumor cell membrane proteins were extracted and dendritic cells(DCs)were acti-vated to confirm that tumor antigens could effectively stimulate the maturation of immature DCs.Mature DC membranes were then mixed with lipids to prepare DCM@MBs,which were characterized for morphology,size,and protein composition by confocal laser scanning microscopy and sodium dodecyl sulfate-polyacrylamide gel electrophoresis.Finally,in vitro co-culture experiments were con-ducted to assess the effect of DCM@MBs on the activation of T cells and their ability for specific killing of tumor cells.Results:In the in vitro DC activation experiment,after stimulation with tumor cell membrane proteins,the 25 μg/mL group had a significant increase in the expression level of MHC class Ⅱ molecule(25.167%±1.203%)on the surface of immature DCs compared with the control group(P<0.001),and DCM@MBs presented with microbubbles encapsulated by red cell membranes,with uniform dispersion and a size of 1-5 μm.In the in vitro co-culture experiment,the amount of breast cancer cells(9.893±0.341)%.Conclusion:The DCM@MBs strategy proposed in this study shows significant potential in tu-mor immunotherapy and can effectively activate T cells and specifically kill and eliminate tumor cells,which provides new ideas for tu-mor immunotherapy.

AIM:To investigate the effect of silent information regulator 1(SIRT1)on the degree of aging and apoptosis in a mouse cardiomyocyte aging model through the regulation of Wnt/β-catenin pathway.METHODS:An in vi-tro aging model was established by inducing HL-1 cells with 40 μmol/L D-galactose(D-Gal).The HL-1 cells were trans-fected with a lentivirus overexpressing SIRT1,and the transfection efficiency was verified by Western blot.Western blot was used to detect the protein expression levels of SIRT1,P53,P21,cleaved caspase-3,B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),β-catenin,Wnt3a and c-Myc.Senescence-associated β-galactosidase(SA-β-Gal)staining was used to detect cellular senescence level.MTT colorimetric assay was used to detect the cell viability,and flow cytometry was used to detect the apoptosis.RESULTS:Treatment of HL-1 mouse cardiomyocytes with D-Gal led to in-creases in the expression levels of aging-related proteins P53 and P21,as well as an increase in SIRT1 protein level.Addi-tionally,the SA-β-Gal staining showed a significant increase in the positive area(P＜0.05).The expression levels of apop-tosis-related proteins cleaved caspase-3 and Bax were elevated,while the level of the anti-apoptotic protein Bcl-2 was re-duced(P＜0.05).There was a marked decrease in cell viability(P＜0.05),and flow cytometry analysis demonstrated a significant increase in cell apoptosis rate(P＜0.05),which was positively correlated with the duration of D-Gal treatment.Overexpression of SIRT1 notably reduced both aging and apoptosis levels after 48 h of D-Gal treatment(P＜0.05).After D-Gal treatment,the expression levels of β-catenin,c-Myc and Wnt3a proteins were up-regulated.However,these levels were reduced when SIRT1 was overexpressed.Moreover,the addition of LiCl,a Wnt/β-catenin pathway agonist,resulted in increased expression levels of β-catenin,c-Myc and Wnt3a proteins compared with the group with SIRT1 overexpres-sion and D-Gal treatment(P＜0.05).CONCLUSION:SIRT1 inhibits cardiomyocyte apoptosis and alleviates cardiomyo-cyte aging through the Wnt/β-catenin pathway.

Objective: To study rDNA ITS (internal transcribed spacers) sequences variation from di erent population of Aquilaria sinensis in main habitat of China. Methods: The rDNA ITS regions of various A. sinensis were ampli ed by PCR method and sequenced, and they were analyzed by means of the software of CLUSTAL and MEGA. Results: The sequences of rDNA ITS region of A. sinensis were reported for the rst time, and the sequences of ITS region were 680bp (ITS1 246bp, 5.8S 163bp, ITS2 271bp). There were 6 variable sites among populations and the genetic distance were 0.0% to 1.1%,which indicated the intraspecific genetic variation was low of A. sinensis. Conclusion: The variation of rDNA ITS sequences can be used to authenticate A.sinensis from di erent geographical regions and their adulterants.