Increased double strand breaks in diabetic β-cells with a p21 response that limits apoptosis
DNA damage and DNA damage response (DDR) pathways in β-cells have received little attention especially in the context of type-2 diabetes. We postulate that p21 plays a key role in DDR by preventing apoptosis, associated through its overexpression triggered by DNA stand breaks (DSBs). Our results sho...
Saved in:
Main Authors: | , , , , , |
---|---|
Other Authors: | |
Format: | Article |
Language: | English |
Published: |
2021
|
Subjects: | |
Online Access: | https://hdl.handle.net/10356/146226 |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Institution: | Nanyang Technological University |
Language: | English |
id |
sg-ntu-dr.10356-146226 |
---|---|
record_format |
dspace |
spelling |
sg-ntu-dr.10356-1462262023-03-05T16:44:46Z Increased double strand breaks in diabetic β-cells with a p21 response that limits apoptosis Tay, Vanessa Shi Yun Devaraj, Surabhi Koh, Tracy Ke, Guo Crasta, Karen Carmelina Yusuf Ali Lee Kong Chian School of Medicine (LKCMedicine) School of Biological Sciences Science::Medicine Cell Death Senescence DNA damage and DNA damage response (DDR) pathways in β-cells have received little attention especially in the context of type-2 diabetes. We postulate that p21 plays a key role in DDR by preventing apoptosis, associated through its overexpression triggered by DNA stand breaks (DSBs). Our results show that β-cells from chronic diabetic mice had a greater extent of DSBs as compared to their non-diabetic counterparts. Comet assays and nuclear presence of γH2AX and 53bp1 revealed increased DNA DSBs in 16 weeks old (wo) db/db β-cells as compared to age matched non-diabetic β-cells. Our study of gene expression changes in MIN6 cell line with doxorubicin (Dox) induced DNA damage, showed that the DDR was similar to primary β-cells from diabetic mice. There was significant overexpression of DDR genes, gadd45a and p21 after a 24-hr treatment. Western blot analysis revealed increased cleaved caspase3 over time, suggesting higher frequency of apoptosis due to Dox-induced DNA strand breaks. Inhibition of p21 by pharmacological inhibitor UC2288 under DNA damage conditions (both in Dox-induced MIN6 cells and older db/db islets) significantly increased the incidence of β-cell apoptosis. Our studies confirmed that while DNA damage, specifically DSBs, induced p21 overexpression in β-cells and triggered the p53/p21 cellular response, p21 inhibition exacerbated the frequency of apoptosis. Ministry of Education (MOE) Published version This research is supported by the Singapore Ministry of Education under its Singapore Ministry of Education Academic Research Fund Tier 1 (MOE2014-T1-001-149) and Tier 2 (MOE2015-T2-2-087) to Y.A.; and separately Tier 1 (MOE2015-T1-002-046-01) and Tier 2 (MOE2018-T2-2-179) to K.C. In addition, this work was partly supported by the LKCMedicine Healthcare Research Fund (Diabetes Research), established through the generous support of alumni of Nanyang Technological University Singapore. 2021-02-02T09:01:10Z 2021-02-02T09:01:10Z 2019 Journal Article Tay, V. S. Y., Devaraj, S., Koh, T., Ke, G., Crasta, K. C., & Yusuf Ali . (2019). Increased double strand breaks in diabetic β-cells with a p21 response that limits apoptosis. Scientific Reports, 9(1), 19341-. doi:10.1038/s41598-019-54554-8 2045-2322 0000-0002-0681-1125 https://hdl.handle.net/10356/146226 10.1038/s41598-019-54554-8 31852915 2-s2.0-85076802619 1 9 en MOE2014-T1-001-149 MOE2015-T2-2-087 MOE2018-T2-2-179 MOE2015-T1-002-046-01 Scientific Reports © 2019 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. application/pdf |
institution |
Nanyang Technological University |
building |
NTU Library |
continent |
Asia |
country |
Singapore Singapore |
content_provider |
NTU Library |
collection |
DR-NTU |
language |
English |
topic |
Science::Medicine Cell Death Senescence |
spellingShingle |
Science::Medicine Cell Death Senescence Tay, Vanessa Shi Yun Devaraj, Surabhi Koh, Tracy Ke, Guo Crasta, Karen Carmelina Yusuf Ali Increased double strand breaks in diabetic β-cells with a p21 response that limits apoptosis |
description |
DNA damage and DNA damage response (DDR) pathways in β-cells have received little attention especially in the context of type-2 diabetes. We postulate that p21 plays a key role in DDR by preventing apoptosis, associated through its overexpression triggered by DNA stand breaks (DSBs). Our results show that β-cells from chronic diabetic mice had a greater extent of DSBs as compared to their non-diabetic counterparts. Comet assays and nuclear presence of γH2AX and 53bp1 revealed increased DNA DSBs in 16 weeks old (wo) db/db β-cells as compared to age matched non-diabetic β-cells. Our study of gene expression changes in MIN6 cell line with doxorubicin (Dox) induced DNA damage, showed that the DDR was similar to primary β-cells from diabetic mice. There was significant overexpression of DDR genes, gadd45a and p21 after a 24-hr treatment. Western blot analysis revealed increased cleaved caspase3 over time, suggesting higher frequency of apoptosis due to Dox-induced DNA strand breaks. Inhibition of p21 by pharmacological inhibitor UC2288 under DNA damage conditions (both in Dox-induced MIN6 cells and older db/db islets) significantly increased the incidence of β-cell apoptosis. Our studies confirmed that while DNA damage, specifically DSBs, induced p21 overexpression in β-cells and triggered the p53/p21 cellular response, p21 inhibition exacerbated the frequency of apoptosis. |
author2 |
Lee Kong Chian School of Medicine (LKCMedicine) |
author_facet |
Lee Kong Chian School of Medicine (LKCMedicine) Tay, Vanessa Shi Yun Devaraj, Surabhi Koh, Tracy Ke, Guo Crasta, Karen Carmelina Yusuf Ali |
format |
Article |
author |
Tay, Vanessa Shi Yun Devaraj, Surabhi Koh, Tracy Ke, Guo Crasta, Karen Carmelina Yusuf Ali |
author_sort |
Tay, Vanessa Shi Yun |
title |
Increased double strand breaks in diabetic β-cells with a p21 response that limits apoptosis |
title_short |
Increased double strand breaks in diabetic β-cells with a p21 response that limits apoptosis |
title_full |
Increased double strand breaks in diabetic β-cells with a p21 response that limits apoptosis |
title_fullStr |
Increased double strand breaks in diabetic β-cells with a p21 response that limits apoptosis |
title_full_unstemmed |
Increased double strand breaks in diabetic β-cells with a p21 response that limits apoptosis |
title_sort |
increased double strand breaks in diabetic β-cells with a p21 response that limits apoptosis |
publishDate |
2021 |
url |
https://hdl.handle.net/10356/146226 |
_version_ |
1759855392275300352 |