Clock Protein Bmal1 and Nrf2 Cooperatively Control Aging or Oxidative Response and Redox Homeostasis by Regulating Rhythmic Expression of Prdx6
Many disorders of aging, including blinding-diseases, are associated with deficiency of brain and muscle arnt-like protein 1 (Bmal1) and, thereby, dysregulation of antioxidant-defense pathway. However, knowledge is limited regarding the role of Bmal1 regulation of antioxidant-pathway in the eye lens...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2020-08-01
|
| Series: | Cells |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-4409/9/8/1861 |
| _version_ | 1797559499843698688 |
|---|---|
| author | Bhavana Chhunchha Eri Kubo Dhirendra P. Singh |
| author_facet | Bhavana Chhunchha Eri Kubo Dhirendra P. Singh |
| author_sort | Bhavana Chhunchha |
| collection | DOAJ |
| description | Many disorders of aging, including blinding-diseases, are associated with deficiency of brain and muscle arnt-like protein 1 (Bmal1) and, thereby, dysregulation of antioxidant-defense pathway. However, knowledge is limited regarding the role of Bmal1 regulation of antioxidant-pathway in the eye lens/lens epithelial cells (LECs) at the molecular level. We found that, in aging human (h)LECs, a progressive decline of nuclear factor erythroid 2-related factor 2 (Nrf2)/ARE (antioxidant response element)-mediated antioxidant genes was connected to Bmal1-deficiency, leading to accumulation of reactive oxygen species (ROS) and cell-death. <i>Bmal1</i>-depletion disrupted Nrf2 and expression of its target antioxidant genes, like <i>Peroxiredoxin 6 (Prdx6)</i>. DNA binding and transcription assays showed that Bmal1 controlled expression by direct binding to E-Box in <i>Prdx6</i> promoter to regulate its transcription. Mutation at E-Box or ARE reduced promoter activity, while disruption of both sites diminished the activity, suggesting that both sites were required for peak <i>Prdx6</i>-transcription. As in aging hLECs, ROS accumulation was increased in <i>Bmal1</i>-deficient cells and the cells were vulnerable to death. Intriguingly, Bmal1/Nrf2/Prdx6 and PhaseII antioxidants showed rhythmic expression in mouse lenses <i>in vivo</i> and were reciprocally linked to ROS levels. We propose that Bmal1 is pivotal for regulating oxidative responses. Findings also reveal a circadian control of antioxidant-pathway, which is important in combating lens/LECs damage induced by aging or oxidative stress. |
| first_indexed | 2024-03-10T17:46:16Z |
| format | Article |
| id | doaj.art-d4279f172b7a4ebd85882925dde5e5a4 |
| institution | Directory Open Access Journal |
| issn | 2073-4409 |
| language | English |
| last_indexed | 2024-03-10T17:46:16Z |
| publishDate | 2020-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Cells |
| spelling | doaj.art-d4279f172b7a4ebd85882925dde5e5a42023-11-20T09:32:37ZengMDPI AGCells2073-44092020-08-0198186110.3390/cells9081861Clock Protein Bmal1 and Nrf2 Cooperatively Control Aging or Oxidative Response and Redox Homeostasis by Regulating Rhythmic Expression of Prdx6Bhavana Chhunchha0Eri Kubo1Dhirendra P. Singh2Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68198, USADepartment of Ophthalmology, Kanazawa Medical University, Ishikawa 9200293, JapanDepartment of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68198, USAMany disorders of aging, including blinding-diseases, are associated with deficiency of brain and muscle arnt-like protein 1 (Bmal1) and, thereby, dysregulation of antioxidant-defense pathway. However, knowledge is limited regarding the role of Bmal1 regulation of antioxidant-pathway in the eye lens/lens epithelial cells (LECs) at the molecular level. We found that, in aging human (h)LECs, a progressive decline of nuclear factor erythroid 2-related factor 2 (Nrf2)/ARE (antioxidant response element)-mediated antioxidant genes was connected to Bmal1-deficiency, leading to accumulation of reactive oxygen species (ROS) and cell-death. <i>Bmal1</i>-depletion disrupted Nrf2 and expression of its target antioxidant genes, like <i>Peroxiredoxin 6 (Prdx6)</i>. DNA binding and transcription assays showed that Bmal1 controlled expression by direct binding to E-Box in <i>Prdx6</i> promoter to regulate its transcription. Mutation at E-Box or ARE reduced promoter activity, while disruption of both sites diminished the activity, suggesting that both sites were required for peak <i>Prdx6</i>-transcription. As in aging hLECs, ROS accumulation was increased in <i>Bmal1</i>-deficient cells and the cells were vulnerable to death. Intriguingly, Bmal1/Nrf2/Prdx6 and PhaseII antioxidants showed rhythmic expression in mouse lenses <i>in vivo</i> and were reciprocally linked to ROS levels. We propose that Bmal1 is pivotal for regulating oxidative responses. Findings also reveal a circadian control of antioxidant-pathway, which is important in combating lens/LECs damage induced by aging or oxidative stress.https://www.mdpi.com/2073-4409/9/8/1861Bmal1Nrf2Prdx6agingoxidative stressantioxidants |
| spellingShingle | Bhavana Chhunchha Eri Kubo Dhirendra P. Singh Clock Protein Bmal1 and Nrf2 Cooperatively Control Aging or Oxidative Response and Redox Homeostasis by Regulating Rhythmic Expression of Prdx6 Cells Bmal1 Nrf2 Prdx6 aging oxidative stress antioxidants |
| title | Clock Protein Bmal1 and Nrf2 Cooperatively Control Aging or Oxidative Response and Redox Homeostasis by Regulating Rhythmic Expression of Prdx6 |
| title_full | Clock Protein Bmal1 and Nrf2 Cooperatively Control Aging or Oxidative Response and Redox Homeostasis by Regulating Rhythmic Expression of Prdx6 |
| title_fullStr | Clock Protein Bmal1 and Nrf2 Cooperatively Control Aging or Oxidative Response and Redox Homeostasis by Regulating Rhythmic Expression of Prdx6 |
| title_full_unstemmed | Clock Protein Bmal1 and Nrf2 Cooperatively Control Aging or Oxidative Response and Redox Homeostasis by Regulating Rhythmic Expression of Prdx6 |
| title_short | Clock Protein Bmal1 and Nrf2 Cooperatively Control Aging or Oxidative Response and Redox Homeostasis by Regulating Rhythmic Expression of Prdx6 |
| title_sort | clock protein bmal1 and nrf2 cooperatively control aging or oxidative response and redox homeostasis by regulating rhythmic expression of prdx6 |
| topic | Bmal1 Nrf2 Prdx6 aging oxidative stress antioxidants |
| url | https://www.mdpi.com/2073-4409/9/8/1861 |
| work_keys_str_mv | AT bhavanachhunchha clockproteinbmal1andnrf2cooperativelycontrolagingoroxidativeresponseandredoxhomeostasisbyregulatingrhythmicexpressionofprdx6 AT erikubo clockproteinbmal1andnrf2cooperativelycontrolagingoroxidativeresponseandredoxhomeostasisbyregulatingrhythmicexpressionofprdx6 AT dhirendrapsingh clockproteinbmal1andnrf2cooperativelycontrolagingoroxidativeresponseandredoxhomeostasisbyregulatingrhythmicexpressionofprdx6 |