TY  - JOUR
A1  - Laubach, Vesselina
A1  - Kaufmann, Roland
A1  - Bernd, August
A1  - Kippenberger, Stefan
A1  - Zöller, Nadja Nicole
T1  - Extrinsic or intrinsic apoptosis by curcumin and light : still a mystery
T2  - International journal of molecular sciences
N2  - Curcumin—a rhizomal phytochemical from the plant Curcuma longa—is well known to inhibit cell proliferation and to induce apoptosis in a broad range of cell lines. In previous studies we showed that combining low curcumin concentrations and subsequent ultraviolet A radiation (UVA) or VIS irradiation induced anti-proliferative and pro-apoptotic effects. There is still debate whether curcumin induces apoptosis via the extrinsic or the intrinsic pathway. To address this question, we investigated in three epithelial cell lines (HaCaT, A431, A549) whether the death receptors CD95, tumor necrosis factor (TNF)-receptor I and II are involved in apoptosis induced by light and curcumin. Cells were incubated with 0.25–0.5 µg/mL curcumin followed by irradiation with 1 J/cm2 UVA. This treatment was combined with inhibitors specific for distinct membrane-bound death receptors. After 24 h apoptosis induction was monitored by quantitative determination of cytoplasmic histone-associated-DNA-fragments. Validation of our test system showed that apoptosis induced by CH11 and TNF-α could be completely inhibited by their respective antagonists. Interestingly, apoptosis induced by curcumin/light treatment was reversed by none of the herein examined death receptor antagonists. These results indicate a mechanism of action independent from classical death receptors speaking for intrinsic activation of apoptosis. It could be speculated that a shift in cellular redox balance might prompt the pro-apoptotic processes
KW  - curcumin
KW  - death receptor
KW  - apoptosis
Y1  - 2019
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/50021
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-500217
SN  - 1422-0067
SN  - 1661-6596
N1  - This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
VL  - 20
IS  - 4, Art. 905
SP  - 1
EP  - 13
PB  - Molecular Diversity Preservation International
CY  - Basel
ER  -