Manganese superoxide dismutase (MnSOD) has been shown to suppress the development of cancer. Tamoxifen (TAM), a nonsteroidal anti-estrogen that is widely used in chemotherapy, is known to be a modulator of antioxidant status. However, the mechanism by which TAM mediates antioxidant enzyme induction remains unclear. In this study we investigated TAM enhancement of MnSOD induction by TNF-alpha. The results show that co-treatment with TAM and TNF-alpha increases the MnSOD promoter/enhancer driven luciferase activity, MnSOD mRNA and protein levels. Interestingly, co-treatment with TAM and TNF-alpha drastically decreases the binding activity of the p50/p50 homodimer and increases that of the p50/p65 heterodimer compared to TNF-alpha alone. This change in DNA binding could not be attributed to a decrease in the level of p50, its precursor, p105, or its inhibitors. Furthermore, TAM did not enhance degradation of IkappaB-alpha. These results suggest that p50/p50 homodimer may act as an inhibitory complex of MnSOD expression. Modulation of the DNA binding activity in favor of the p50/p65 complex may enhance NF-kappaB mediated induction of MnSOD by TAM. These findings reveal a potential novel mechanism for the induction of the human MnSOD gene.

Download full-text PDF

Source
http://dx.doi.org/10.1038/sj.onc.1205448DOI Listing

Publication Analysis

Top Keywords

mnsod
8
mnsod expression
8
expression modulation
8
co-treatment tam
8
tam tnf-alpha
8
binding activity
8
p50/p50 homodimer
8
dna binding
8
tam
7
tnf-alpha
5

Similar Publications

Ethnopharmacological Relevance: Rostellularia procumbens (L) Nees. (R. procumbens) is a classical Chinese herbal medicine that has been used for effective treatment of kidney disease for nearly a thousand years in China.

View Article and Find Full Text PDF

Comparison of the aquatic toxicity of diquat and its metabolites to zebrafish Danio rerio.

Sci Rep

December 2024

Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China.

Diquat (DQ) is a non-selective, fast-acting herbicide that is extensively used in aquatic systems. DQ has been registered as the substitute for paraquat due to its lower toxicity. However, the widespread presence of DQ in aquatic systems can pose an ecological burden on aquatic organisms.

View Article and Find Full Text PDF

Manganese is one of the trace elements necessary for organisms to maintain normal biological activities and is also a cofactor for manganese superoxide dismutase (Mn-SOD) and manganese peroxidase (MnP). In order to find a simple and effective method to rejuvenate the degenerated strains, we explored the effect of the exogenous addition of MnSO on the antioxidant vigour and productivity of degenerated strains of . The results showed that the exogenous MnSO had no significant effect on the non-degenerated strain T0, but it could effectively increase the mycelial growth rate, mycelial biomass, and LBL decolouring ability of the degenerated strains T10 and T19, and reduce the production cycle and increased the biological efficiency of T10; it helped the severely degenerated T19 to regrow its fruiting body; and it also significantly increased the viability of the matrix-degrading enzymes such as EG, Lac, Xyl, etc.

View Article and Find Full Text PDF

Resynthesis of Damaged Fe-S Cluster Proteins Protects Against Oxidative Stress in the Absence of Mn-Superoxide Dismutase.

J Fungi (Basel)

November 2024

Department of Molecular Biotechnology and Microbiology, Institute of Biotechnology, Faculty of Science and Technology, University of Debrecen, H-4032 Debrecen, Hungary.

Article Synopsis
  • Manganese superoxide dismutase (Mn-SOD) is vital for maintaining mitochondrial function, and its absence heightens sensitivity to oxidative stress and iron limitation.
  • Deleting the Mn-SOD gene resulted in increased vulnerability to oxidative damage and made fungal spores more susceptible to destruction by human immune cells.
  • Analysis revealed that this gene deletion notably altered the oxidative stress response, impacting the regulation of genes related to iron management and protein synthesis in response to stress.
View Article and Find Full Text PDF

Studies suggest that vitamin D (VitD) may reduce oxidative stress (OS) in multiple sclerosis (MS) patients. This study aimed to compare the effects of various VitD doses on OS in relapsing-remitting MS (RRMS). A 6-month supplementation was introduced using two doses of VitD: 2000 IU/day in the high-dose group (HD, = 23) and 15,960 IU/month in the low-dose group (LD, = 29).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!