p53 inhibitor pifithrin α hydrobromide  (MedChemExpress)

Journal: bioRxiv

Article Title: Tau-induced mitochondrial reverse electron transport drives neurodegeneration

doi: 10.64898/2026.04.04.716514

Figure Lengend Snippet: a, Representative WB and quantification showing effect of VDAC, Hsp70, and Hsp90 inhibitor treatment on tau entry into mitochondria in the in vitro import assay. Mitochondrial p-tau level is normalized with the C-II protein SDHA. b , RET-ROS measurements after p-tau import into control or inhibitor-treated mitochondria. c , Representative WB and quantification showing total PHF-1 tau level in the in vitro import assay mixture. Total p-tau level is normalized with actin, which is known to be associated with mitochondria. d , RET-ROS measurements in control or inhibitor-treated mitochondria without p-tau import. e , WBs and quantification showing knockdown efficiency by VDAC1, Hsp70, and Hsp90 siRNAs. f , Representative WBs and quantification showing the effect of VDAC1, Hsp70, and Hsp90 siRNAs on tau entry into mitochondria in the in vitro import assay and total PHF-1 tau level in the in vitro import assay. g , h , RET-ROS measurements in mitochondria from control or siRNA treated cells with ( g ) or without ( h ) p-tau import into mitochondria. All data are means ± SEM; statistical significance was determined by one-way ANOVA with Dunnett’s multiple test ( a, b, c, d, f, g, h ), or two-tailed unpaired Student’s t test ( e ). *p<0.05; **p<0.01; ***p<0.001; ****p<0.0001. Each data point in a - h represents an independent experimental repeat.

Article Snippet: HEK293T cells were treated with the VDAC inhibitor DIDS (50 μM, Sigma, Cat#309795), Hsp70 inhibitor pifithrin-α hydrobromide (20μM, MedChemExpress, Cat#HY-15484), Hsp90 inhibitor Geldanamycin (1 μM, SelleckChem, Cat#S2713) for 6h.

Techniques: In Vitro, Control, Knockdown, Two Tailed Test

Journal: bioRxiv

Article Title: Tau-induced mitochondrial reverse electron transport drives neurodegeneration

doi: 10.64898/2026.04.04.716514

Figure Lengend Snippet: a, Representative WBs and quantification showing effect of VDAC, Hsp70, and Hsp90 inhibitors on the mitochondrial level of PHF-1 tau and total PHF-1 tau in the elav-GS>tau-R406W flies. In this GeneSwitch inducible model, tau-R406W expression is tightly controlled by the addition of RU486 to the fly food. Mitochondrial fractions or total cell lysates were used for WB, and mitochondrial or total PHF-1 p-tau was normalized by SDHA or actin. b , RET-ROS measurements in the mitochondria from control or inhibitor treated elav-GS>tau-R406W flies after tau induction by RU486. c - e , aversive taste memory assays in VDACi ( c ), Hsp70i ( d ), and Hsp90i ( e ) treated elav-GS>tau-R406W flies after tau induction by RU486. f , Climbing activity assay in VDACi, Hsp70i, and Hsp90i treated elav-GS>tau-R406W flies after tau induction by RU486. g , h , RET ( g ) and aversive taste memory ( h ) assays of control flies without tau transgene expression. All data are means ± SEM; statistical significance was determined by one-way ANOVA with Dunnett’s multiple test ( a, b, f, g ), or group analysis using multiple t test with Sidak-Bonferroni multiple comparison ( c , d , e , h ). *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001. Each data point represents independent experimental repeat. Three sets of flies with 10-12 flies in each set were used for the behavioral assays.

Article Snippet: HEK293T cells were treated with the VDAC inhibitor DIDS (50 μM, Sigma, Cat#309795), Hsp70 inhibitor pifithrin-α hydrobromide (20μM, MedChemExpress, Cat#HY-15484), Hsp90 inhibitor Geldanamycin (1 μM, SelleckChem, Cat#S2713) for 6h.

Techniques: Expressing, Control, Activity Assay, Comparison

Journal: bioRxiv

Article Title: Tau-induced mitochondrial reverse electron transport drives neurodegeneration

doi: 10.64898/2026.04.04.716514

Figure Lengend Snippet: a , Effect of H 2 O 2 and FK866 on the viability of tau-P301L hiPSC neurons and isogenic wildtype controls after 24h treatment, and the rescuing effect of CPT. b , Effect of H 2 O 2 and FK866 co-treatment on the viability of control and tau KD hiPSC neurons and the rescuing effect of CPT. c, d , Effect of DES treatment on the viability of control and tau KD hiPSC neurons ( c ) and the rescuing effect of CPT in DES (20 mM) treated control hiPSC neurons ( d ). e - g , WB and quantification showing the effect of inhibiting VDAC, Hsp70, or Hsp90 on PHF-1 tau entry into mitochondria without affecting total PHF-1 tau levels ( e ), and quantification of the effect of inhibitor treatment on RET activity ( f ) and stress sensitivity ( g ) of APP hiPSC neurons. h , Measurement of RET ROS and NAD + /NADH in purified mitochondria from control and tau-WT-EGFP or tau-S2A-EGFP-transfected normal hiPSC neurons. i , Representative images and quantification of p-S262 tau in tau-WT-EGFP or tau-S2A-EGFP transfected control hiPSC neurons with or without DES treatment. j , Measurement of RET ROS and NAD + /NADH in purified mitochondria from EGFP or MKI-EGFP transduced APP hiPSC neurons. k , Representative images and quantification of p-S262 tau in EGFP or MKI-EGFP transfected APP hiPSC neurons. l, m , Immunoblots ( l ) and quantification ( m ) showing effects of the various treatments on normalized levels of p-tau species in APP hiPSC neurons. n, o , Immunoblots ( n ) and quantification ( o ) showing effect of DES or DES/CPT co-treatment on normalized levels of p-tau species in control hiPSC neurons. All data are means ± SEM; statistical significance was determined by one-way ANOVA with Tukey’s post hoc test ( a, b, d, g, h, i, o ), two-way ANOVA with Tukey’s post hoc test ( c ), two-tailed unpaired Student’s t test ( j, k ), or one-way ANOVA with Dunnett’s multiple test ( e, f , m ). *p<0.05; **p<0.01; ***p<0.001; ****p<0.0001 ( a, b, c, d, g : n=6/group from 3 biological replicates and 2 wells/experiment; e, f, h, j, m, o : n=3 biological replicates; i, k : n=3 biological replicates, and each data point represents an average of 6 cells/experiment).

Article Snippet: HEK293T cells were treated with the VDAC inhibitor DIDS (50 μM, Sigma, Cat#309795), Hsp70 inhibitor pifithrin-α hydrobromide (20μM, MedChemExpress, Cat#HY-15484), Hsp90 inhibitor Geldanamycin (1 μM, SelleckChem, Cat#S2713) for 6h.

Techniques: Control, Activity Assay, Purification, Transfection, Western Blot, Two Tailed Test

Journal: bioRxiv

Article Title: Tau-induced mitochondrial reverse electron transport drives neurodegeneration

doi: 10.64898/2026.04.04.716514

Figure Lengend Snippet: a, Representative WBs and quantification showing effect of VDAC1, Hsp70, and Hsp90 lenti-shRNAs on the expression of the target proteins. b , Representative WBs and quantification showing effect of VDAC1, Hsp70, and Hsp90 lenti-shRNAs on the levels of mitochondrially localized PHF-1 tau and total PHF-1 tau in APP hiPSC neurons. Mitochondrial fractions or total cell lysates were used for WB, and mitochondrial or total PHF-1 p-tau was normalized by SDHA or actin. c , RET-ROS measurements in mitochondria from control or VDAC1, Hsp70, and Hsp90 lenti-shRNA treated APP hiPSC neurons. d , e , RET ( d ) and stress sensitivity ( e ) assays of control iPSC neurons treated with VDAC1, Hsp70, and Hsp90 inhibitors. All data are means ± SEM; statistical significance was determined by two-tailed unpaired Student’s t test ( a ) or one-way ANOVA with Dunnett’s multiple test ( b-e ). *p<0.05; **p<0.01; ***p<0.001; ****p<0.0001 ( e : n=6/group from 3 biological replicates and 2 wells/experiment).

Article Snippet: HEK293T cells were treated with the VDAC inhibitor DIDS (50 μM, Sigma, Cat#309795), Hsp70 inhibitor pifithrin-α hydrobromide (20μM, MedChemExpress, Cat#HY-15484), Hsp90 inhibitor Geldanamycin (1 μM, SelleckChem, Cat#S2713) for 6h.

Techniques: Expressing, Control, shRNA, Two Tailed Test

Journal: International Journal of Molecular Sciences

Article Title: Lycium barbarum Glycopeptide Inhibits Colorectal Cancer Cell Proliferation via Activating p53/p21 Pathway and Inducing Cellular Senescence

doi: 10.3390/ijms26157091

Figure Lengend Snippet: Effects of LbGP on p53/p21 expression and cell cycle distribution in CT26 cells. ( A ) Western blot and band intensity quantification of p53 and p21 expression after 72 h of LbGP treatment. Two 0 μg/mL samples were used as technical replicates for both protein blots. GAPDH served as the loading control. ( B ) Flow cytometry analysis of cell cycle distribution at 72 h, showing an increased proportion of cells in S phase and a decreased proportion in G2/M phase. n = 3. * p < 0.05; n.s., not significant compared to the control (0 μg/mL).

Article Snippet: The p53 inhibitor Pifithrin-α hydrobromide was purchased from Selleck Chemicals, Houston, TX, USA (S2929).

Techniques: Expressing, Western Blot, Control, Flow Cytometry

Journal: International Journal of Molecular Sciences

Article Title: Lycium barbarum Glycopeptide Inhibits Colorectal Cancer Cell Proliferation via Activating p53/p21 Pathway and Inducing Cellular Senescence

doi: 10.3390/ijms26157091

Figure Lengend Snippet: LbGP increases p53/p21 expression and reduces tumor cell proliferation in vivo. ( A ) Western blot quantification of p53 and p21 expressions in tumor tissues at day 21. β-actin served as the loading control. ( B ) Immunohistochemistry (IHC) staining and quantification of Ki-67–positive cells in tumor sections (200× and 400×; scale bars = 100 μm and 25 μm, Leica; antibody 1:150). Brown nuclei represent Ki-67–positive cells. n = 8 per group; data represent mean ± SD. * p < 0.05; compared to PBS.

Article Snippet: The p53 inhibitor Pifithrin-α hydrobromide was purchased from Selleck Chemicals, Houston, TX, USA (S2929).

Techniques: Expressing, In Vivo, Western Blot, Control, Immunohistochemistry