BACKGROUND Esophageal squamous cell carcinoma(ESCC)is a malignant tumor with high morbidity and mortality,and easy to develop resistance to chemotherapeutic agents.Telomeres are DNA-protein complexes located at the te...BACKGROUND Esophageal squamous cell carcinoma(ESCC)is a malignant tumor with high morbidity and mortality,and easy to develop resistance to chemotherapeutic agents.Telomeres are DNA-protein complexes located at the termini of chro-mosomes in eukaryotic cells,which are unreplaceable in maintaining the stability and integrity of genome.Telomerase,an RNA-dependent DNA polymerase,play vital role in telomere length maintain,targeting telomerase is a promising therapeutic strategy for cancer.KYSE150 and KYSE410 cells were cultured and exposed to various concentrations of BIBR1532.Cell viability was assessed at 48 hours and 72 hours to determine the IC50 values.The effects of BIBR1532 on ESCC cell proliferation,migration,and cellular senescence were evaluated using the cell counting kit-8 assay,plate colony formation assay,scratch assay,transwell assay,andβ-galactosidase staining,respectively.Western blotting was performed to detect the expression of RESULTS The IC50 values for KYSE150 and KYSE410 cells after 48 hours of BIBR1532 exposure were 48.53μM and 39.59μM,respectively.These values decreased to 37.22μM and 22.71μM,respectively,following a longer exposure of 72 hours.BIBR1532 exhibited dose-dependent effects on KYSE150 and KYSE410 cells,including decreased hTERT expression,inhibition of proliferation and metastasis,and induction of cellular senescence.Mechanistically,BIBR1532 upregulated the expression of the DDR protein,γ-H2AX,and activated the ataxia telangiectasia and Rad3-related protein(ATR)/check point kinase 1(CHK-1)and ataxia-telangiectasia mutated gene(ATM)/CHK2 pathways.BIBR1532 downregulated the expression of telomere-binding proteins,including telomeric-repeat binding factor 1(TRF1),TRF2,protection of telomeres 1,and TIN2-interacting protein 1.In a nude mouse xenograft model,BIBR1532 significantly suppressed tumor growth,reduced hTERT expression,and increasedγ-H2AX protein levels.Hematoxylin and eosin staining of various organs,including the heart,liver,spleen,lungs,and kidneys,revealed no apparent adverse effects.CONCLUSION BIBR1532 exerts anti-cancer effects on ESCC by inducing DDR through the ATR/CHK1 and ATM/CHK2 pathways and downregulating the expression of telomere-binding proteins.展开更多
Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by...Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by suppressing the expression of aldose reductase in peripheral nerves of diabetes mellitus rats. The high-fat and high-carbohydrate model rats were established by intraperitoneal injection of streptozotocin. Peripheral neuropathy occurred in these rats after sustaining high blood glucose for 8 weeks. At 12 weeks after streptozotocin injection, rats were intragastrically administered epalrestat 100 mg/kg daily for 6 weeks. Transmission electron microscope revealed that the injuries to myelinated nerve fibers, non-myelinated nerve fibers and Schwann cells of rat sciatic nerves had reduced compared to rats without epalrestat administuation. Western blot assay and immunohistochemical results demonstrated that after intervention with epalrestat, the activities of antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase gradually increased, but aldose reductase protein expression gradually diminished. Results confirmed that epalrestat could protect against diabetic peripheral neuropathy by relieving oxidative stress and suppressing the polyol pathway.展开更多
Apoptosis and autophagy play crucial roles during Bombyx mori metamorphosis and in response to various adverse conditions, including starvation. Recently, calpain, one of the major intracellular proteases, has been re...Apoptosis and autophagy play crucial roles during Bombyx mori metamorphosis and in response to various adverse conditions, including starvation. Recently, calpain, one of the major intracellular proteases, has been reported to be involved in apoptosis and autophagy in mammals. BmATG5 and BmATG6 have been identified to mediate apoptosis following autophagy induced by 20-hydroxyecdysone and starvation in B. mori. However, B. mori calpains and their functions remain unclear. In this study, phylogenetic analysis of calpains from B. mori, Drosophila melanogaster and Homo sapiens were performed and the results showed distinct close relationships of BmCalpain-A/B with DmCalpain- A/B, BmCalpain-C with DmCalpain-C, and BmCalpain-7 with HsCalpain-7. Then, the expression profiles of BmCalpains were analyzed by quantitative real-time polymerase chain reaction, and results showed that expression ofBmCalpain-A/B, BmCalpain-C and BmCalpain-7 was significantly increased during B. mori metamorphosis and induced in the fat body and midgut of starved larvae, which is consistent with the expression profiles ofBmAtgS, BmAtg6 and BmCaspase-1. Moreover, the apoptosis-associated cleavage of BmATG6 in Bm-12 cells was significantly enhanced when BmCalpain-A/B and BmCalpain-7 were induced by starvation, and was partially inhibited by the inhibitor of either calpain or caspase, but completely inhibited when both types of inhibitors were applied together. Our results indicated that BmCalpains, including BmCalpain-A/B, -C and -7, may be involved in autophagy and apoptosis during B. mori metamorphosis and after starvation, and may also contribute to the apoptosis-associated cleavage of BmATG6.展开更多
基金Supported by the Scientific Research Development Plan Project or the Scientific Research Foundation for Advanced Talents,Affiliated Hospital of North Sichuan Medical College,No.2023MPZK017,No.2023ZD001,No.2023-2ZD002,and No.2023GC009Science and Technology Support Program of Nanchong,No.22SXQT0001+1 种基金Youth Medical Innovation Research Project,or Medical Research Project of Sichuan Province,No.Q23047 and No.S23020Development of a Scientific Research Plan for the Doctoral Scientific Research Foundation of the North Sichuan Medical College,No.CBY22-ZDA03.
文摘BACKGROUND Esophageal squamous cell carcinoma(ESCC)is a malignant tumor with high morbidity and mortality,and easy to develop resistance to chemotherapeutic agents.Telomeres are DNA-protein complexes located at the termini of chro-mosomes in eukaryotic cells,which are unreplaceable in maintaining the stability and integrity of genome.Telomerase,an RNA-dependent DNA polymerase,play vital role in telomere length maintain,targeting telomerase is a promising therapeutic strategy for cancer.KYSE150 and KYSE410 cells were cultured and exposed to various concentrations of BIBR1532.Cell viability was assessed at 48 hours and 72 hours to determine the IC50 values.The effects of BIBR1532 on ESCC cell proliferation,migration,and cellular senescence were evaluated using the cell counting kit-8 assay,plate colony formation assay,scratch assay,transwell assay,andβ-galactosidase staining,respectively.Western blotting was performed to detect the expression of RESULTS The IC50 values for KYSE150 and KYSE410 cells after 48 hours of BIBR1532 exposure were 48.53μM and 39.59μM,respectively.These values decreased to 37.22μM and 22.71μM,respectively,following a longer exposure of 72 hours.BIBR1532 exhibited dose-dependent effects on KYSE150 and KYSE410 cells,including decreased hTERT expression,inhibition of proliferation and metastasis,and induction of cellular senescence.Mechanistically,BIBR1532 upregulated the expression of the DDR protein,γ-H2AX,and activated the ataxia telangiectasia and Rad3-related protein(ATR)/check point kinase 1(CHK-1)and ataxia-telangiectasia mutated gene(ATM)/CHK2 pathways.BIBR1532 downregulated the expression of telomere-binding proteins,including telomeric-repeat binding factor 1(TRF1),TRF2,protection of telomeres 1,and TIN2-interacting protein 1.In a nude mouse xenograft model,BIBR1532 significantly suppressed tumor growth,reduced hTERT expression,and increasedγ-H2AX protein levels.Hematoxylin and eosin staining of various organs,including the heart,liver,spleen,lungs,and kidneys,revealed no apparent adverse effects.CONCLUSION BIBR1532 exerts anti-cancer effects on ESCC by inducing DDR through the ATR/CHK1 and ATM/CHK2 pathways and downregulating the expression of telomere-binding proteins.
基金supported by a grant from the National Natural Science Foundation of China,No.81060141
文摘Epalrestat is a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy. This study assumed that epalrestat had a protective effect on diabetic peripheral nerve injury by suppressing the expression of aldose reductase in peripheral nerves of diabetes mellitus rats. The high-fat and high-carbohydrate model rats were established by intraperitoneal injection of streptozotocin. Peripheral neuropathy occurred in these rats after sustaining high blood glucose for 8 weeks. At 12 weeks after streptozotocin injection, rats were intragastrically administered epalrestat 100 mg/kg daily for 6 weeks. Transmission electron microscope revealed that the injuries to myelinated nerve fibers, non-myelinated nerve fibers and Schwann cells of rat sciatic nerves had reduced compared to rats without epalrestat administuation. Western blot assay and immunohistochemical results demonstrated that after intervention with epalrestat, the activities of antioxidant enzymes such as superoxide dismutase, catalase and glutathione peroxidase gradually increased, but aldose reductase protein expression gradually diminished. Results confirmed that epalrestat could protect against diabetic peripheral neuropathy by relieving oxidative stress and suppressing the polyol pathway.
基金This study was supported by grants from National Basic Research Program of China （973 program） （No. 2012CB 114600）, National Natural Science Foundation of China （No. 31101765）, and Natural Science Foundation of Guangdong Province of China （No. 2015A030313396）.
文摘Apoptosis and autophagy play crucial roles during Bombyx mori metamorphosis and in response to various adverse conditions, including starvation. Recently, calpain, one of the major intracellular proteases, has been reported to be involved in apoptosis and autophagy in mammals. BmATG5 and BmATG6 have been identified to mediate apoptosis following autophagy induced by 20-hydroxyecdysone and starvation in B. mori. However, B. mori calpains and their functions remain unclear. In this study, phylogenetic analysis of calpains from B. mori, Drosophila melanogaster and Homo sapiens were performed and the results showed distinct close relationships of BmCalpain-A/B with DmCalpain- A/B, BmCalpain-C with DmCalpain-C, and BmCalpain-7 with HsCalpain-7. Then, the expression profiles of BmCalpains were analyzed by quantitative real-time polymerase chain reaction, and results showed that expression ofBmCalpain-A/B, BmCalpain-C and BmCalpain-7 was significantly increased during B. mori metamorphosis and induced in the fat body and midgut of starved larvae, which is consistent with the expression profiles ofBmAtgS, BmAtg6 and BmCaspase-1. Moreover, the apoptosis-associated cleavage of BmATG6 in Bm-12 cells was significantly enhanced when BmCalpain-A/B and BmCalpain-7 were induced by starvation, and was partially inhibited by the inhibitor of either calpain or caspase, but completely inhibited when both types of inhibitors were applied together. Our results indicated that BmCalpains, including BmCalpain-A/B, -C and -7, may be involved in autophagy and apoptosis during B. mori metamorphosis and after starvation, and may also contribute to the apoptosis-associated cleavage of BmATG6.
