Riboflavin (Vitamin B2) Deficiency Induces Apoptosis Mediated by Endoplasmic Reticulum Stress and the CHOP Pathway in HepG2 Cells
Abstract
:1. Introduction
2. Materials and Methods
2.1. Cell Culture and Experimental Protocols
2.2. Cell Structure and Microstructure Observations
2.3. Cell Number and Viability
2.4. GR Activity and GSH Content
2.5. Cell Apoptosis
2.6. RNA Analysis and Real-Time PCR
2.7. Western Blot Analysis
2.8. Data and Statistical Analyses
3. Results
3.1. RD Inhibited the Cell Proliferation of HepG2cells and Decreased Relative Cell Viability
3.2. RD Inhibited GR Activity and Decreased GSH Content
3.3. RD-Induced ER Stress and Apoptosis
3.4. 4-PBA Attenuated ER Stress and Apoptosis Induced by RD
3.5. Knockdown of CHOP Attenuated RD-Induced ER Stress and Apoptosis
4. Discussion
- Even though apoptosis was inhibited by CHOP interference, unfolded/misfolded proteins were still retained in the ER, and ER stress persisted in the riboflavin-depleted cells.
- Riboflavin depletion resulted in the low expression of flavoproteins, leading to metabolic disorders.
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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siRNA | Sense | Antisense |
---|---|---|
CHOP | 5′-GAACAGGAGAAUGAAAGGAAATT-3′ | 5′-UUUCCUUUCAUUCUCCUGUUCTT-3′ |
NC | 5′-UUCUCCGAACGUGUCACGUTT-3′ | 5′-ACGUGACACGUUCGGAGAATT-3′ |
Genes | Forward | Reverse |
---|---|---|
CHOP | 5′-ACCAAGGGAGAACCAGGAAACG-3′ | 5′-TCACCATTCGGTCAATCAGAGC-3′ |
GRP78 | 5′-CGGGCAAAGATGTCAGGAAAG-3′ | 5′-TTCTGGACGGGCTTCATAGTAGAC-3′ |
ATF6 | 5′-AGCGGAGCCACTGAAGGAAGATA-3′ | 5′-GCGTTGGTACTGTCTGAATAATGATGG-3′ |
PDIA6 | 5′-GGAGGTCAGTATGGTGTTCAGGGAT-3′ | 5′-CTGCCACCTTGGTAATCTTCTGGTC-3′ |
BAX | 5′-GGCCCACCAGCTCTGAGCAGA-3′ | 5′-GCCACGTGGGCGGTCCCAAAGT-3′ |
BCL2 | 5′-GTGGAGGAGCTCTTCAGGGA-3′ | 5′-AGGCACCCAGGGTGAGCAA-3′ |
CASP3 | 5′-TCTGACTGGAAAGCCGAAACT-3′ | 5′-AGTGACTGGATGAACCATGAC-3′ |
β-actin | 5′-AATCGTGCGTGACATTAAGGAGAAG-3′ | 5′-CAGGAAGGAAGGCTGGAAGAGTG-3′ |
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Zhang, B.; Cao, J.-T.; Wu, Y.-B.; Gao, K.-X.; Xie, M.; Zhou, Z.-K.; Tang, J.; Hou, S.-S. Riboflavin (Vitamin B2) Deficiency Induces Apoptosis Mediated by Endoplasmic Reticulum Stress and the CHOP Pathway in HepG2 Cells. Nutrients 2022, 14, 3356. https://doi.org/10.3390/nu14163356
Zhang B, Cao J-T, Wu Y-B, Gao K-X, Xie M, Zhou Z-K, Tang J, Hou S-S. Riboflavin (Vitamin B2) Deficiency Induces Apoptosis Mediated by Endoplasmic Reticulum Stress and the CHOP Pathway in HepG2 Cells. Nutrients. 2022; 14(16):3356. https://doi.org/10.3390/nu14163356
Chicago/Turabian StyleZhang, Bo, Jun-Ting Cao, Yong-Bao Wu, Ke-Xin Gao, Ming Xie, Zheng-Kui Zhou, Jing Tang, and Shui-Sheng Hou. 2022. "Riboflavin (Vitamin B2) Deficiency Induces Apoptosis Mediated by Endoplasmic Reticulum Stress and the CHOP Pathway in HepG2 Cells" Nutrients 14, no. 16: 3356. https://doi.org/10.3390/nu14163356
APA StyleZhang, B., Cao, J. -T., Wu, Y. -B., Gao, K. -X., Xie, M., Zhou, Z. -K., Tang, J., & Hou, S. -S. (2022). Riboflavin (Vitamin B2) Deficiency Induces Apoptosis Mediated by Endoplasmic Reticulum Stress and the CHOP Pathway in HepG2 Cells. Nutrients, 14(16), 3356. https://doi.org/10.3390/nu14163356