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Optically Pure Double-Stranded Dinuclear Ir(III) Metallohelices Enabled Chirality-Induced Photodynamic Responses
Xuezhao Li1, Zhicheng Wang2, Xiaorou Hao1
1School of Chemistry, State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China.
Journal of the American Chemical Society
|June 27, 2023
Summary
Chiral iridium(III) metallohelices show potent enantiomer-dependent photodynamic therapy (PDT) responses. The Δ2S4-H enantiomer exhibits exceptionally high PDT efficacy by migrating to the nucleus and inhibiting key nuclear proteins.
Area of Science:
- Coordination Chemistry
- Photodynamic Therapy
- Metallodrugs
Background:
- Chiral drug enantiomers interact differently with biomolecules, impacting biological behavior.
- Understanding these interactions is crucial for drug design and development.
Purpose of the Study:
- To design and synthesize optically pure, cationic, dinuclear Iridium(III)-metallohelices.
- To investigate their enantiomer-dependent photodynamic therapy (PDT) responses.
- To elucidate the mechanisms underlying their differential biological activities.
Main Methods:
- Synthesis of chiral dinuclear Iridium(III)-metallohelices (Λ2R4-H and Δ2S4-H).
- In vitro and in vivo studies of photodynamic therapy (PDT) responses.
- Proteomic analysis and molecular docking simulations.
Main Results:
- Optically pure metallohelices showed negligible dark toxicity but significant light-induced toxicity.
- Δ2S4-H exhibited a remarkably high photocytotoxicity index (PI) of 63,966, compared to 428 for Λ2R4-H.
- Δ2S4-H migrated from mitochondria to the nucleus post-irradiation, inhibiting nuclear proteins and triggering oxidative stress.
Conclusions:
- Chirality of iridium(III) metallohelices significantly influences PDT efficacy.
- Δ2S4-H represents a highly effective PDT agent with a unique mechanism of action.
- This study provides insights for designing novel chiral helical metallodrugs with enhanced therapeutic potential.
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