Prevention of neuronal apoptosis by astrocytes through thiol-mediated stress response modulation and accelerated recovery from proteotoxic stress

Gutbier, Simon; Spreng, Anna‐Sophie; Delp, Johannes; Schildknecht, Stefan; Karreman, Christiaan; Suciu, Ilinca; Brunner, Thomas; Groettrup, Marcus; Leist, Marcel

doi:10.1038/s41418-018-0229-x

Cited by 39 publications

(57 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As additional functional parameter, we measured proteasomal activity. In neurons, this cellular function is impaired when mitochondria are dysfunctional and ATP levels drop (Gutbier et al 2018b;Terron et al 2018). We found here that proteasome activity was indeed affected in a similar way as ATP levels, with an Fig.…”

Section: Increased Sensitivity Of Gal Neurons For Toxicity Of the Comsupporting

confidence: 57%

“…Parallel plates that were not used to assess viability and neurite outgrowth were used to assess proteasomal activity. Activity measurements were performed exactly as described in (Gutbier et al 2018b). The assay is based on the replacement of cell culture medium by HBSS buffer containing a cell permeable proteasomal substrate [MeOSuc-Gly-Leu-Phe-AMC, 25 µM (Bachem, Bubendorf, Switzerland)] after 24 h of toxicant exposure.…”

Section: Proteasomal Activitymentioning

confidence: 99%

See 1 more Smart Citation

Development of a neurotoxicity assay that is tuned to detect mitochondrial toxicants

et al. 2019

Self Cite

View full text Add to dashboard Cite

Many neurotoxicants affect energy metabolism in man, but currently available test methods may still fail to predict mito-and neurotoxicity. We addressed this issue using LUHMES cells, i.e., human neuronal precursors that easily differentiate into mature neurons. Within the NeuriTox assay, they have been used to screen for neurotoxicants. Our new approach is based on culturing the cells in either glucose or galactose (Glc-Gal-NeuriTox) as the main carbohydrate source during toxicity testing. Using this Glc-Gal-NeuriTox assay, 52 mitochondrial and non-mitochondrial toxicants were tested. The panel of chemicals comprised 11 inhibitors of mitochondrial respiratory chain complex I (cI), 4 inhibitors of cII, 8 of cIII, and 2 of cIV; 8 toxicants were included as they are assumed to be mitochondrial uncouplers. In galactose, cells became more dependent on mitochondrial function, which made them 2-3 orders of magnitude more sensitive to various mitotoxicants. Moreover, galactose enhanced the specific neurotoxicity (destruction of neurites) compared to a general cytotoxicity (plasma membrane lysis) of the toxicants. The Glc-Gal-NeuriTox assay worked particularly well for inhibitors of cI and cIII, while the toxicity of uncouplers and non-mitochondrial toxicants did not differ significantly upon glucose ↔ galactose exchange. As a secondary assay, we developed a method to quantify the inhibition of all mitochondrial respiratory chain functions/ complexes in LUHMES cells. The combination of the Glc-Gal-NeuriTox neurotoxicity screening assay with the mechanistic follow up of target site identification allowed both, a more sensitive detection of neurotoxicants and a sharper definition of the mode of action of mitochondrial toxicants. Keywords Neurotoxicity • Mitotoxicity • Metabolic reprogramming • High-throughput toxicity screening • High content imaging • Mechanistic safety assessment Abbreviations ADP Adenosine triphosphate AOP Adverse outcome pathway Asp l-Aspartate ATP Adenosine diphosphate cAMP N6,2′-O-Dibutyryladenosine 3′,5′-cyclic monophosphate cI-V MRC complex I-V CNS Central nervous system Cyt c Cytochrome c FAD(H 2) Flavin adenine dinucleotide (FAD: oxidized, FADH2: reduced) FCCP Carbonyl cyanide-4-(trifluoromethoxy) phenylhydrazone G6P Glucose-6-phosphate Gal1P Galactose-1-phosphate GALK Galactokinase GALT Galactose-1-phosphate uridylyltransferase GDNF Glial derived neurotrophic factor Glc1P Glucose-1-phosphate Hex Hexose, in this study either glucose or galactose HK Hexokinase Lac Lactate Mal Malate MoA Mode of action MPP 1-Methyl-4-phenylpyridinium Electronic supplementary material The online version of this article (

show abstract

Section: Increased Sensitivity Of Gal Neurons For Toxicity Of the Comsupporting

confidence: 57%

Section: Proteasomal Activitymentioning

confidence: 99%

Development of a neurotoxicity assay that is tuned to detect mitochondrial toxicants

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…Simpler test systems were combined to obtain advanced complex test systems to better resemble the in vivo situation. These approaches include, for instance, the use of mixed cell cultures (Gutbier et al 2018 ), 3D organoids and neurospheres (Brull et al 2020 ; Hiemstra et al 2019 ; Kobolak et al 2020 ) and microphysiological systems (MPS), e.g. four-organ-chips developed to interconnect miniaturized human intestine, liver, brain and kidney equivalents (Ramme et al 2019 ) and improved iPSC cell differentiation to hepatocytes (Boon et al 2020 ).…”

Section: The Repository Of Nams Available For Nam-enhanced Raxmentioning

confidence: 99%

Setting the stage for next-generation risk assessment with non-animal approaches: the EU-ToxRisk project experience

et al. 2020

Self Cite

View full text Add to dashboard Cite

In 2016, the European Commission launched the EU-ToxRisk research project to develop and promote animal-free approaches in toxicology. The 36 partners of this consortium used in vitro and in silico methods in the context of case studies (CSs). These CSs included both compounds with a highly defined target (e.g. mitochondrial respiratory chain inhibitors) as well as compounds with poorly defined molecular initiation events (e.g. short-chain branched carboxylic acids). The initial project focus was on developing a science-based strategy for read-across (RAx) as an animal-free approach in chemical risk assessment. Moreover, seamless incorporation of new approach method (NAM) data into this process (= NAM-enhanced RAx) was explored. Here, the EU-ToxRisk consortium has collated its scientific and regulatory learnings from this particular project objective. For all CSs, a mechanistic hypothesis (in the form of an adverse outcome pathway) guided the safety evaluation. ADME data were generated from NAMs and used for comprehensive physiological-based kinetic modelling. Quality assurance and data management were optimized in parallel. Scientific and Regulatory Advisory Boards played a vital role in assessing the practical applicability of the new approaches. In a next step, external stakeholders evaluated the usefulness of NAMs in the context of RAx CSs for regulatory acceptance. For instance, the CSs were included in the OECD CS portfolio for the Integrated Approach to Testing and Assessment project. Feedback from regulators and other stakeholders was collected at several stages. Future chemical safety science projects can draw from this experience to implement systems toxicology-guided, animal-free next-generation risk assessment.

show abstract

“…These human-derived mesencephalic neural precursor cells can be differentiated into post-mitotic dopaminergic neurons (Schildknecht et al 2009 ; Scholz et al 2011 ). Such cells have been frequently used in combination with PD-related toxicants to model PD neuropathology, including neuronal loss and intracytoplasmic protein aggregates (Devos et al 2014 ; Efremova et al 2015 ; Gutbier et al 2018b ; Harris et al 2018 ; Hollerhage et al 2017 ; Poltl et al 2012 ; Schildknecht et al 2009 ; Scholz et al 2011 ).…”

Section: Introductionmentioning

confidence: 99%

Design and evaluation of bi-functional iron chelators for protection of dopaminergic neurons from toxicants

et al. 2020

Self Cite

View full text Add to dashboard Cite

While the etiology of non-familial Parkinson's disease (PD) remains unclear, there is evidence that increased levels of tissue iron may be a contributing factor. Moreover, exposure to some environmental toxicants is considered an additional risk factor. Therefore, brain-targeted iron chelators are of interest as antidotes for poisoning with dopaminergic toxicants, and as potential treatment of PD. We, therefore, designed a series of small molecules with high affinity for ferric iron and containing structural elements to allow their transport to the brain via the neutral amino acid transporter, LAT1 (SLC7A5). Five candidate molecules were synthesized and initially characterized for protection from ferroptosis in human neurons. The promising hydroxypyridinone SK4 was characterized further. Selective iron chelation within the physiological range of pH values and uptake by LAT1 were confirmed. Concentrations of 10-20 µM blocked neurite loss and cell demise triggered by the parkinsonian neurotoxicants, methyl-phenyl-pyridinium (MPP +) and 6-hydroxydopamine (6-OHDA) in human dopaminergic neuronal cultures (LUHMES cells). Rescue was also observed when chelators were given after the toxicant. SK4 derivatives that either lacked LAT1 affinity or had reduced iron chelation potency showed altered activity in our assay panel, as expected. Thus, an iron chelator was developed that revealed neuroprotective properties, as assessed in several models. The data strongly support the role of iron in dopaminergic neurotoxicity and suggests further exploration of the proposed design strategy for improving brain iron chelation.

show abstract

Prevention of neuronal apoptosis by astrocytes through thiol-mediated stress response modulation and accelerated recovery from proteotoxic stress

Cited by 39 publications

References 61 publications

Development of a neurotoxicity assay that is tuned to detect mitochondrial toxicants

Development of a neurotoxicity assay that is tuned to detect mitochondrial toxicants

Setting the stage for next-generation risk assessment with non-animal approaches: the EU-ToxRisk project experience

Design and evaluation of bi-functional iron chelators for protection of dopaminergic neurons from toxicants

Contact Info

Product

Resources

About