Journal: Acta Pharmaceutica Sinica. B

Article Title: Vitamin A and its analogues modulate MUFAs metabolism to improve ferroptosis and aging by direct targeting of ACSL3

doi: 10.1016/j.apsb.2025.11.004

Figure Lengend Snippet: Vitamin A and its metabolites inhibit ferroptosis independent of antioxidant capacity or RAR/RXR activation. (A) Illustration of the structures of VA and ATRA. (B) Measurement of the EC 50 values of VA and ATRA towards RSL3 (0.5 μmol/L) or Erastin (10 μmol/L) induced ferroptosis in HT-1080 cells. Cells were treated with drugs for 24 h. (C) RAL suppressed RSL3 and Erastin-induced ferroptosis in HT-1080 cells. (D) Viability of HT-1080 GPX4 -KO cells treated with the indicated compounds for 24 h after withdrawal of Fer-1, which is essential for the survival of GPX4 -KO cells. (E) The antioxidative capacity of VA (50 μmol/L), ATRA (50 μmol/L) and RAL (50 μmol/L) was analyzed by the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. Trolox (50 μmol/L) was used as a positive control. (F) The effect of VA, ATRA and RAL on the autoxidation of C11 BODIPY 581/591 initiated by AAPH in EggPC liposomes was measured by FENIX assay. Fer-1 was used as a positive control. (G) Protein expression levels of GPX4, SLC7A11, ACSL4, SCD1, FSP1, HO-1 and NRF2 in HT-1080 cells were analyzed by Western blot. Cells were treated with VA (1 μmol/L) or ATRA (10 μmol/L) in the presence or absence of RSL3 (0.25 μmol/L) for 2.5 h or Erastin (10 μmol/L) for 8 h. (H) Protein expression levels of IRP1, TFRC and FTH1 in HT-1080 cells were analyzed by Western blot. Cells were treated with VA (1 μmol/L) or ATRA (10 μmol/L) in the presence or absence of RSL3 (0.25 μmol/L) for 2.5 h or Erastin (10 μmol/L) for 8 h. (I, J) Cell viability of HT-1080 cells after co-treatment with RSL3 and VA or ATRA in the presence of pan-RAR antagonist AGN193109 (20 μmol/L) (I) or pan-RXR antagonist HX531 (20 μmol/L) (J). (K) The protective effects of VA or ATRA on RSL3-induced ferroptosis in RXRA and RXRB knockout HT-1080 cells. (L) Viability of HT-1080 cells treated with different doses of RAR agonists Ch55 and Adapalene (ADA) under RSL3 (0.5 μmol/L) and Erastin (10 μmol/L)-induced ferroptosis for 24 h. Data shown represent the mean ± SD ( n = 3). ∗∗ P < 0.01, and ∗∗∗ P < 0.001, indicating significant differences between groups. ns means no significance.

Article Snippet: All- trans -retinal (T5256), Fenretinide (T1872), Acitretin (T1330), AGN193109 (TQ0097), HX531( T22843 ), Ch55 ( T14946 ), Adapalene (T1093) and A939572 (T4515) were purchased from TargetMOI (Shanghai, China).

Techniques: Activation Assay, Positive Control, Liposomes, Expressing, Western Blot, Knock-Out

Journal: bioRxiv

Article Title: Epithelial sensing of vitamin A shapes intestinal antimicrobial defense

doi: 10.64898/2026.03.08.710399

Figure Lengend Snippet: (A) Vitamin A-derived retinol is metabolized to RA, which activates retinoic acid receptors (RARs). RARs bind target gene promoters to drive RA-dependent transcription. (B) HT-29 cells (human intestinal epithelial cells) were treated with the RAR antagonist BMS493 or the RAR agonist Ch55 and simultaneously stimulated overnight with RA and IL-22. REG3G transcripts were quantified by qPCR. Each data point represents an independent experimental replicate (n=6 per group). (C) HCT-116, a transfection-competent human intestinal epithelial cell line expressing RARA and RARG , was treated for 24 hours with an siRNA targeting either gene and then stimulated overnight with retinol and IL-22. REG3G transcripts were quantified by qPCR. Each data point represents an independent experimental replicate (n=4 per group). (D) IEC-specific disruption of RAR signaling using a dominant-negative RAR (dnRAR) knock-in allele. dnRAR mice harbor a loxP -flanked STOP cassette upstream of a dominant-negative RAR open reading frame. The dnRAR is derived from a mutant human RARα (RAR403) lacking the ligand-dependent transactivation domain and functions as a pan-RAR inhibitor. Crossing dnRAR mice with Villin-Cre transgenic mice excises the STOP cassette in IECs, resulting in IEC-selective expression of dnRAR and inhibition of RAR signaling. (E) qPCR analysis of Reg3g expression in small intestines of conventional dnRAR fl/fl (n=12) and dnRAR IEC (n=17) mice from five litters, and germ-free wild-type mice (n=21). (F) Immunofluorescence microscopy of REG3G in small intestines of dnRAR fl/fl and dnRAR IEC mice. Sections were stained for REG3G and counterstained with DAPI. Scale bar, 100 μ m. Images are representative of at least three fields per sample and two independent experiments (three littermates per group). (G) Mean fluorescence intensities of at least 150 villi from the images represented in (F) were quantified across at least two mice of each genotype. RAR, retinoic acid receptor; RA, retinoic acid; IEC, intestinal epithelial cell; REG3G, regenerating islet-derived protein 3γ; siRNA, small interfering RNA; dnRAR, dominant negative retinoic acid receptor; Conv, conventional; GF, germ-free. Means ± SEM are plotted; *p < 0.05; **p < 0.01; ***p<0.001; ns, not significant by Mann-Whitney test. See also .

Article Snippet: Pharmacologic modulation of retinoic acid receptor (RAR) activity was performed using the pan-RAR antagonist BMS493 (Fisher Scientific) or the pan-RAR agonist Ch55 (Tocris).

Techniques: Derivative Assay, Transfection, Expressing, Disruption, Dominant Negative Mutation, Knock-In, Mutagenesis, Transgenic Assay, Inhibition, Immunofluorescence, Microscopy, Staining, Fluorescence, Small Interfering RNA, MANN-WHITNEY

Journal: Communications Biology

Article Title: Retinoic acid receptor alpha inhibits ferroptosis by promoting thioredoxin and protein phosphatase 1F in lung adenocarcinoma

doi: 10.1038/s42003-024-06452-7

Figure Lengend Snippet: a CCK8 assays to detect the cell viability of A549 and PC9 cells treated with RSL3 (2 μM), RSL3 (2 μM) plus DFO (100 μM) or fer-1 (20 μM) for 24 h after incubating with DMSO, Ch55 (5 μM), AM580 (5 μM) ATRA (20 μM) or AGN193109 (5 μM) for 24 h. ( n = 4 biologically independent experiments, Student t -test). b – e MDA level ( b ) lipid peroxidation ( c ), mitochondrial membrane potential (MMP) by TMRE ( d ), and labile iron pool (LIP) by CA-AM ( e ) were accessed in A549 and PC9 cells treated with DMSO or RSL3 (1 μM) for 24 h after incubating with DMSO, Ch55 (5 μM), AM580 (5 μM) ATRA (20 μM) or AGN193109 (5 μM) for 24 h. ( n = 3 biologically independent experiments, Student t -test). f Light microscopy images showed the degrees of “ballooning phenotype” in A549 and PC9 cells treated with DMSO or RSL3 (1 μM) for 24 h after incubating with DMSO, Ch55 (5 μM), AM580 (5 μM) ATRA (20 μM) or AGN193109 (5 μM) for 24 h. Scale bar:50 μm. The zoomed-in figures, scale bar: 250 μm. ns, not significant; * p < 0.05; ** p < 0.01; *** p < 0.001; **** p < 0.0001.

Article Snippet: The RSL3, Imidazole Ketone Erastin (IKE), Erastin, Ferric ammonium citrate (FAC), RARA inhibitor AGN193109, RARA activator Ch55 and AM580, PAK inhibitor FRAX486, cisplatin (CDDP), and pemetrexed were acquired from Topscience (Shanghai, China) and were dissolved in dimethyl sulfoxide (DMSO).

Techniques: Membrane, Light Microscopy

Journal: Communications Biology

Article Title: Retinoic acid receptor alpha inhibits ferroptosis by promoting thioredoxin and protein phosphatase 1F in lung adenocarcinoma

doi: 10.1038/s42003-024-06452-7

Figure Lengend Snippet: a qRT-PCR and WB assays confirmed the mRNA and protein expression level of RARA in A549 and PC9 cells after transfection with NC (control shRNA), RARA-SH1, or RARA-SH2 lentivirus. ( n = 3 biologically independent experiments, Student t -test) ( b ) CCK8 assays to detect the cell viability of NC, RARA-SH1, or RARA-SH2 groups in A549 and PC9 cells treated with a gradient dose of RSL3 or IKE for 24 h. ( n = 4 biologically independent experiments, two-way ANOVA) ( c ) CCK8 assays to detect the cell viability of NC, RARA-SH1, or RARA-SH2 groups in A549 and PC9 cells treated with DMSO or RSL3 (2 μM) for 24 h after incubating with DMSO, Ch55 (5 μM), AM580 (5 μM) ATRA (20 μM) or AGN193109 (5 μM) for 24 h. ( n = 4 biologically independent experiments, Student t -test). d – g MDA level ( d ), lipid peroxidation ( e ), MMP by TMRE ( g ) and LIP by CA-AM ( g ) were accessed in NC, RARA-SH1 groups of A549 and PC9 cells treated with DMSO or RSL3 (1 μM) for 24 h after incubating with DMSO, Ch55 (5 μM), AM580 (5 μM) ATRA (20 μM) or AGN193109 (5 μM) for 24 h. ( n = 3 biologically independent experiments, Student t -test) ns, not significant * p < 0.05; ** p < 0.01; *** p < 0.001;**** p < 0.0001.

Article Snippet: The RSL3, Imidazole Ketone Erastin (IKE), Erastin, Ferric ammonium citrate (FAC), RARA inhibitor AGN193109, RARA activator Ch55 and AM580, PAK inhibitor FRAX486, cisplatin (CDDP), and pemetrexed were acquired from Topscience (Shanghai, China) and were dissolved in dimethyl sulfoxide (DMSO).

Techniques: Quantitative RT-PCR, Expressing, Transfection, Control, shRNA

Journal: NPJ Precision Oncology

Article Title: ALDH1A1 promotes PARP inhibitor resistance by enhancing retinoic acid receptor-mediated DNA polymerase θ expression

doi: 10.1038/s41698-023-00411-x

Figure Lengend Snippet: a, b PEO1 and OVCAR3 cells were treated with RAR agonist CH55 or RAR antagonist AGN 193109 for 48 h, qRT-PCR and immunoblotting were conducted to determine the mRNA ( a ) and protein ( b ) levels of POLQ /Polθ, respectively. The mRNA level of RARB was also determined to validate the effect of RAR agonist and antagonist on the RAR signaling. c , d PEO1 and OVCAR3 cells were transfected with two RARA siRNA for 48 h, qRT-PCR and immunoblotting were conducted to determine the mRNA ( c ) and protein ( d ) levels of RARA /RARα and POLQ /Polθ, respectively. Measurements were taken from distinct samples. N = 3, bar: s.d., ** P < 0.01. The relative amounts of analyzed proteins were listed under the corresponding band. The arrow indicates the specific RARα band.

Article Snippet: All- trans -Retinoic Acid (ATRA) was purchased from Sigma Aldrich (Cat. No. R2625), RAR agonist CH55 (Cat. No. 2020) and RAR antagonist AGN 193109 (Cat. No. 5758) were purchased from Tocris Biosciences.

Techniques: Quantitative RT-PCR, Western Blot, Transfection

Journal: NPJ Precision Oncology

Article Title: ALDH1A1 promotes PARP inhibitor resistance by enhancing retinoic acid receptor-mediated DNA polymerase θ expression

doi: 10.1038/s41698-023-00411-x

Figure Lengend Snippet: a The conserved base sequence of RARα binding site was identified using JASPAR. b The putative RARE was identified in the promoter region of the POLQ gene. c The ChIP assay with the anti-RARα antibody and normal IgG was conducted to analyze the binding of RARα to the promoter region of the POLQ gene. d , e The ChIP assay with the anti-H3K27ac antibody was conducted to determine the effect of RAR agonist CH55, RA ( d ), and ALDH1A1 inhibitor NCT-505 ( e ) on the histone H3K27 acetylation around the RARE region of the POLQ gene. f – h The ChIP assay with the anti-H3K27me3 antibody was conducted to determine the effect of CH55 ( f ), RAR antagonist AGN 193109 ( g ), and NCT-505 ( h ) on the histone H3K27 methylation around the RARE region of the POLQ gene. Measurements were taken from distinct samples. N = 3, bar: s.d., ** P < 0.01.

Article Snippet: All- trans -Retinoic Acid (ATRA) was purchased from Sigma Aldrich (Cat. No. R2625), RAR agonist CH55 (Cat. No. 2020) and RAR antagonist AGN 193109 (Cat. No. 5758) were purchased from Tocris Biosciences.

Techniques: Sequencing, Binding Assay, Methylation