TY - JOUR
T1 - Toxicity, recovery, and resilience in a 3D dopaminergic neuronal in vitro model exposed to rotenone
AU - Harris, Georgina
AU - Eschment, Melanie
AU - Orozco, Sebastian Perez
AU - McCaffery, J. Michael
AU - Maclennan, Richard
AU - Severin, Daniel
AU - Leist, Marcel
AU - Kleensang, Andre
AU - Pamies, David
AU - Maertens, Alexandra
AU - Hogberg, Helena T.
AU - Freeman, Dana
AU - Kirkwood, Alfredo
AU - Hartung, Thomas
AU - Smirnova, Lena
N1 - Publisher Copyright:
© 2018, The Author(s).
PY - 2018/8/1
Y1 - 2018/8/1
N2 - To date, most in vitro toxicity testing has focused on acute effects of compounds at high concentrations. This testing strategy does not reflect real-life exposures, which might contribute to long-term disease outcome. We used a 3D-human dopaminergic in vitro LUHMES cell line model to determine whether effects of short-term rotenone exposure (100 nM, 24 h) are permanent or reversible. A decrease in complex I activity, ATP, mitochondrial diameter, and neurite outgrowth were observed acutely. After compound removal, complex I activity was still inhibited; however, ATP levels were increased, cells were electrically active and aggregates restored neurite outgrowth integrity and mitochondrial morphology. We identified significant transcriptomic changes after 24 h which were not present 7 days after wash-out. Our results suggest that testing short-term exposures in vitro may capture many acute effects which cells can overcome, missing adaptive processes, and long-term mechanisms. In addition, to study cellular resilience, cells were re-exposed to rotenone after wash-out and recovery period. Pre-exposed cells maintained higher metabolic activity than controls and presented a different expression pattern in genes previously shown to be altered by rotenone. NEF2L2, ATF4, and EAAC1 were downregulated upon single hit on day 14, but unchanged in pre-exposed aggregates. DAT and CASP3 were only altered after re-exposure to rotenone, while TYMS and MLF1IP were downregulated in both single-exposed and pre-exposed aggregates. In summary, our study shows that a human cell-based 3D model can be used to assess cellular adaptation, resilience, and long-term mechanisms relevant to neurodegenerative research.
AB - To date, most in vitro toxicity testing has focused on acute effects of compounds at high concentrations. This testing strategy does not reflect real-life exposures, which might contribute to long-term disease outcome. We used a 3D-human dopaminergic in vitro LUHMES cell line model to determine whether effects of short-term rotenone exposure (100 nM, 24 h) are permanent or reversible. A decrease in complex I activity, ATP, mitochondrial diameter, and neurite outgrowth were observed acutely. After compound removal, complex I activity was still inhibited; however, ATP levels were increased, cells were electrically active and aggregates restored neurite outgrowth integrity and mitochondrial morphology. We identified significant transcriptomic changes after 24 h which were not present 7 days after wash-out. Our results suggest that testing short-term exposures in vitro may capture many acute effects which cells can overcome, missing adaptive processes, and long-term mechanisms. In addition, to study cellular resilience, cells were re-exposed to rotenone after wash-out and recovery period. Pre-exposed cells maintained higher metabolic activity than controls and presented a different expression pattern in genes previously shown to be altered by rotenone. NEF2L2, ATF4, and EAAC1 were downregulated upon single hit on day 14, but unchanged in pre-exposed aggregates. DAT and CASP3 were only altered after re-exposure to rotenone, while TYMS and MLF1IP were downregulated in both single-exposed and pre-exposed aggregates. In summary, our study shows that a human cell-based 3D model can be used to assess cellular adaptation, resilience, and long-term mechanisms relevant to neurodegenerative research.
KW - 3D LUHMES
KW - Cellular defence
KW - Gene response
KW - Neurodegeneration
KW - Pesticide
KW - Recovery
KW - Resilience
KW - Rotenone
UR - http://www.scopus.com/inward/record.url?scp=85049143580&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85049143580&partnerID=8YFLogxK
U2 - 10.1007/s00204-018-2250-8
DO - 10.1007/s00204-018-2250-8
M3 - Article
C2 - 29955902
AN - SCOPUS:85049143580
SN - 0340-5761
VL - 92
SP - 2587
EP - 2606
JO - Archives of Toxicology
JF - Archives of Toxicology
IS - 8
ER -