Selenium Concentrations for Maximisation of Thioredoxin Reductase 2 Activity and Upregulation of Its Gene Transcripts in Senescent Human Fibroblasts
Thioredoxin reductase 2 (TR2) activity, its gene transcripts, and hydrogen peroxide (H2O2) generation were examined in biochemically identified early-senescent P20 and senescent P30 fibroblasts subcultured in media (MEM2–MEM8) containing Se concentrations at 1.25, 2.5, 3.5, 5.0, 6.0, 7.0, and 8.0 µM...
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| Format: | Article |
| Language: | English |
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MDPI AG
2017-10-01
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| Series: | Antioxidants |
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| Online Access: | https://www.mdpi.com/2076-3921/6/4/83 |
| _version_ | 1827837281287798784 |
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| author | Hazem K. Ghneim |
| author_facet | Hazem K. Ghneim |
| author_sort | Hazem K. Ghneim |
| collection | DOAJ |
| description | Thioredoxin reductase 2 (TR2) activity, its gene transcripts, and hydrogen peroxide (H2O2) generation were examined in biochemically identified early-senescent P20 and senescent P30 fibroblasts subcultured in media (MEM2–MEM8) containing Se concentrations at 1.25, 2.5, 3.5, 5.0, 6.0, 7.0, and 8.0 µM, respectively. Although TR2 activity was moderately increased in P20 and P30 cells subcultured in routine growth medium (MEM1), there were progressive significant activity increases in the same cells subcultured in MEM2–MEM8. Such increases were proportional to Se concentration and peaked in P30 cells incubated with MEM7 and MEM8. H2O2 generation underwent progressive increases in MEM1-incubated P20 and P30 cells, peaking in the latter, but was gradually lowered in those incubated with MEM2–MEM8, reaching its lowest values when cells were incubated with MEM7 and MEM8. In parallel, TR2 gene transcripts underwent significant upregulation in P20 cells and higher magnitude upregulation in P30 cells subcultured in MEM2, MEM4, and MEM8 compared to those recorded for P5 pre-senescent cells subcultured in the same media. The computed Km Se values with respect to TR2 activity equaled 3.34 and 4.98 µM for P20 and P30 cells, respectively, with corresponding Vmax activities of 55.9 and 96.2 nmol/min/mg protein. It is concluded that senescent P30 cells utilize more Se and achieve maximal TR2 activity to combat oxidative injury. |
| first_indexed | 2024-03-12T06:40:21Z |
| format | Article |
| id | doaj.art-a381287aef1741fbae8aa1ede5379082 |
| institution | Directory Open Access Journal |
| issn | 2076-3921 |
| language | English |
| last_indexed | 2024-03-12T06:40:21Z |
| publishDate | 2017-10-01 |
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| record_format | Article |
| series | Antioxidants |
| spelling | doaj.art-a381287aef1741fbae8aa1ede53790822023-09-03T01:04:55ZengMDPI AGAntioxidants2076-39212017-10-01648310.3390/antiox6040083antiox6040083Selenium Concentrations for Maximisation of Thioredoxin Reductase 2 Activity and Upregulation of Its Gene Transcripts in Senescent Human FibroblastsHazem K. Ghneim0Chair of Medical and Molecular Genetics Research, Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud University, Riyadh 11433, Saudi ArabiaThioredoxin reductase 2 (TR2) activity, its gene transcripts, and hydrogen peroxide (H2O2) generation were examined in biochemically identified early-senescent P20 and senescent P30 fibroblasts subcultured in media (MEM2–MEM8) containing Se concentrations at 1.25, 2.5, 3.5, 5.0, 6.0, 7.0, and 8.0 µM, respectively. Although TR2 activity was moderately increased in P20 and P30 cells subcultured in routine growth medium (MEM1), there were progressive significant activity increases in the same cells subcultured in MEM2–MEM8. Such increases were proportional to Se concentration and peaked in P30 cells incubated with MEM7 and MEM8. H2O2 generation underwent progressive increases in MEM1-incubated P20 and P30 cells, peaking in the latter, but was gradually lowered in those incubated with MEM2–MEM8, reaching its lowest values when cells were incubated with MEM7 and MEM8. In parallel, TR2 gene transcripts underwent significant upregulation in P20 cells and higher magnitude upregulation in P30 cells subcultured in MEM2, MEM4, and MEM8 compared to those recorded for P5 pre-senescent cells subcultured in the same media. The computed Km Se values with respect to TR2 activity equaled 3.34 and 4.98 µM for P20 and P30 cells, respectively, with corresponding Vmax activities of 55.9 and 96.2 nmol/min/mg protein. It is concluded that senescent P30 cells utilize more Se and achieve maximal TR2 activity to combat oxidative injury.https://www.mdpi.com/2076-3921/6/4/83seleniumthioredoxin reductase 2senescent fibroblastsoxidative stress |
| spellingShingle | Hazem K. Ghneim Selenium Concentrations for Maximisation of Thioredoxin Reductase 2 Activity and Upregulation of Its Gene Transcripts in Senescent Human Fibroblasts Antioxidants selenium thioredoxin reductase 2 senescent fibroblasts oxidative stress |
| title | Selenium Concentrations for Maximisation of Thioredoxin Reductase 2 Activity and Upregulation of Its Gene Transcripts in Senescent Human Fibroblasts |
| title_full | Selenium Concentrations for Maximisation of Thioredoxin Reductase 2 Activity and Upregulation of Its Gene Transcripts in Senescent Human Fibroblasts |
| title_fullStr | Selenium Concentrations for Maximisation of Thioredoxin Reductase 2 Activity and Upregulation of Its Gene Transcripts in Senescent Human Fibroblasts |
| title_full_unstemmed | Selenium Concentrations for Maximisation of Thioredoxin Reductase 2 Activity and Upregulation of Its Gene Transcripts in Senescent Human Fibroblasts |
| title_short | Selenium Concentrations for Maximisation of Thioredoxin Reductase 2 Activity and Upregulation of Its Gene Transcripts in Senescent Human Fibroblasts |
| title_sort | selenium concentrations for maximisation of thioredoxin reductase 2 activity and upregulation of its gene transcripts in senescent human fibroblasts |
| topic | selenium thioredoxin reductase 2 senescent fibroblasts oxidative stress |
| url | https://www.mdpi.com/2076-3921/6/4/83 |
| work_keys_str_mv | AT hazemkghneim seleniumconcentrationsformaximisationofthioredoxinreductase2activityandupregulationofitsgenetranscriptsinsenescenthumanfibroblasts |