Fig. 3: Phenotype-based screening identifies lutein ability to rescue behavioral and cellular defects in models of Human Complex I deficiency.

a–b Compounds rescuing more than 20% of the population. Bar graphs represent means ± SEM and corresponding data points. n ≥ 40 over two to five biologically independent experiments, two-tailed Student’s t test. p values in a: nuo-5 DMSO vs isovitexin 10 µM p = 0.0379, nuo-5 DMSO vs lutein 1 µM p = 0.0102. p values in b: lpd-5 DMSO vs lutein 50 µM p = 0.022, lpd-5 DMSO vs lutein 1 µM p < 0.0001, lpd-5 DMSO vs kahalalide F 0.5 µM p = 0.001. c Representative pictures of 4 wells of a 12-well plate 3 days after eggs hatching. Scale bars, 1 mm, n ≥ 40 over four biologically independent experiments. d Relative mRNA expression of nuo-5 assessed by qPCR. One-way ANOVA. ****p values < 0.0001. Three biologically independent experiments. e Quantification of lutein ratio addressed with the use of peak 1515.775 cm⁻¹ as Lutein’s characteristic peak and ratio equation (Lutein/CH₂). Normalized on control values, n ≥ 73 over three biologically independent experiments. Box plots indicate median (middle line), 25th, 75th percentile (box) and 2.5th and 97.5th percentile (whiskers) as well as outliers (single points). p-values: con vs con + lutein p = 0.0001, nuo-5 vs nuo-5 lutein p = 0,007, lpd-5 vs lpd-5 + lutein p = 0.005. f, h Chemotaxis curves and g, i maximum chemotaxis index, reached after 240 minutes using as attractants f, g 1 µl of 1% pyrazine or h, i 1 µl of 1% butanol, n ≥ =100 over three biologically independent experiments. p values in g: con vs nuo-5 p = 0.0412, nuo-5 vs nuo-5 + lutein p < 0.0001, lpd-5 vs lpd-5 + lutein p = 0.0015. p values in i: nuo-5 vs nuo-5 + lutein p = 0.007, lpd-5 vs lpd-5 + lutein p = 0.006. j Pharyngeal pump frequency in adult worms fed for one generation with RNAi, n ≥ 26 over three biologically independent experiments, the two conditions were tested separately thus, unpaired one-way ANOVA was used. con vs nuo-5 p < 0.0001, con vs lpd-5 p = 0.0003, nuo-5 vs nuo-5 + lutein p = 0.0469, lpd-5 vs lpd-5 + lutein p = 0.00182. k ROS production, measured with MitoSOX Red, quantified in the pharyngeal bulb, n ≥ 48 over two biologically independent experiments. con vs nuo-5 p < 0.0001, con vs lpd-5 p < 0.0001, nuo-5 vs nuo-5 + lutein p = 0.033, lpd-5 vs lpd-5 + lutein p = 0.0003. l Quantification of GFP nuclear translocation in a strain expressing the P_hlh-30::HLH-30::GFP transgene, n ≥ 48 over three biologically independent experiments. con vs nuo-5 p < 0.0001, con vs lpd-5 p = 0.0003, nuo-5 vs nuo-5 + lutein p = 0.0049, lpd-5 vs lpd-5 + lutein p < 0.0001. m ROS production in patients’ derived skin fibroblasts after 24 h incubation with lutein. n ≥ 107 over three biologically independent experiments. con vs NDUFS1 p < 0.0001, con vs NDUFS4 p = 0.0002, NDUFS1 vs NDUFS1 + lutein p = 0.0357. In f–l animals were fed bacteria transformed either with empty-vector (con) or with vector expressing dsRNA against nuo-5 or lpd-5 treated with lutein 1 µM (unless otherwise specified) or left untreated. Box plots indicate median (middle line), 25th, 75th percentile (box) and 5th and 95th percentile (whiskers) as well as outliers (single points), except otherwise indicated. Bar graphs represent means ± SEM. Asterisks (*) denote significant differences vs control, # denote differences among conditions. Two-way ANOVA followed by Tukey’s multiple-comparisons test, unless otherwise specified. Data for all panels are provided as a Source Data file.