Neuroprotection of Indole-Derivative Compound NC001-8 by the Regulation of the NRF2 Pathway in Parkinson’s Disease Cell Models

Figure 4

Counteraction of the neuroprotective and antioxidant effects of NC001-8 by knockdown of NRF2. (a) Scheme of the experimental design. The SH-SY5Y cells were treated with small interfering (si)RNA for NRF2 from day 14 to day 16 followed by 2 days of 1 mM MPP⁺ treatment. (b) Analysis of qRT-PCR and (c) Western blot of NRF2, NQO1, and cleaved caspase 3 in DAergic neurons treated with MPP⁺, NC001-8, and/or siNRF2. Data were normalized to GAPDH and compared to cells with no treatment (, independent assays). (d) Cell viability (total counts with cells), (e) LDH assay (total counts with cells), (f) ROS level, and quantification of neurite outgrowth of DAergic neurons (total counts with more than 500 cells) treated with MPP⁺, NC001-8, and/or siNRF2. Data were normalized to MPP⁺-treated cells with scrambled control (siCTR) (, independent assays). . DAergic: dopaminergic; GAPDH: glyceraldehyde 3-phosphate dehydrogenase; LDH, lactate dehydrogenase; MPP⁺: 1-methyl-4-phenylpyridinium; NRF2: nuclear factor erythroid 2-related factor 2; NQO1: NAD(P)H dehydrogenase, quinone 1; ROS: reactive oxygen species; qRT-PCR: quantitative reverse transcription-polymerase chain reaction.

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