Journal: iScience

Article Title: Development of a succinyl CoA:3-ketoacid CoA transferase inhibitor selective for peripheral tissues that improves glycemia in obesity

doi: 10.1016/j.isci.2025.112336

Figure Lengend Snippet: PSSI-51 selectively inhibits SCOT without interacting with canonical targets of DPBPs (A) Quantification of recombinant SCOT enzymatic activity and acetoacetyl CoA production rates in the presence of dimethyl sulfoxide (DMSO) (vehicle control) and PSSI-51 (500, 250, and 125 nmol/L) (n = 7–9 biological replicates). (B) Evaluation of C 14 βOHB oxidation rates in the isolated working mouse heart in response to vehicle control or PSSI-51 treatment (n = 5–6 animals). (C) Assessment of potential cerebral uptake of PSSI-51 and pimozide using PAMPA. (D) Fluorescence-based assay in U2OS red cAMP Nomad D2R cells to measure inhibition of dopamine-induced cAMP mobilization by PSSI-51, compared with pimozide and the positive control blenonserin ( n = 3 biological replicates). (E) Quantitative fluorescence analysis of dopamine agonistic activity ( n = 3 biological replicates). (F) Schematic of targeted site-directed mutagenesis within SCOT binding site. (G) SCOT enzymatic activity of the recombinant mutant SCOT (Y115A/I323A) and rate of acetoacetyl CoA production in the presence of DMSO (vehicle control) and the PSSI-51 (500 nmol/L) ( n = 3 technical replicates). (H) Circulating βOHB levels following PSSI-51 administration 16 h prior to oral ketone ester intake. Data are presented as mean ± SEM. Statistical significance was determined using Student’s t test or one-way ANOVA, followed by a Bonferroni post hoc correction where appropriate. Statistical thresholds set at ∗ p < 0.05 vs. vehicle control, $ p < 0.05 vs. pimozide, # p < 0.05 vs. dopamine. RMSD; root-mean-square deviation, RMSF; root-mean-square fluctuation, HP Std; high permeability standard, LP Std; low permeability standard; P e : permeability coefficients.

Article Snippet: Plasma protein binding: Fresh blood collected from Sprague-Dawley rats was spiked with 1000 and 5000 ng/mL of PSSI-51 or pimozide.

Techniques: Recombinant, Activity Assay, Control, Isolation, PAMPA Assay, Fluorescence, Inhibition, Positive Control, Mutagenesis, Binding Assay, Permeability

Journal: iScience

Article Title: Development of a succinyl CoA:3-ketoacid CoA transferase inhibitor selective for peripheral tissues that improves glycemia in obesity

doi: 10.1016/j.isci.2025.112336

Figure Lengend Snippet: Selective Inhibition of peripheral ketone body metabolism by PSSI-51 (A) SCOT activity assay in the brain, kidney and soleus muscle isolated from mouse treated PSSI-51, and pimozide (n = 3–4 animals). (B) Representative PET images of untreated fed and untreated fasted mice 1 h post injection of S-[ 18 F]FβOHB and time-activity curves for fasted to fed brain and muscle over 60 min ( n = 4 animals). (C) Representative PET images of vehicle treated (fasted) and PSSI-51 treated (fasted) mice 1 h post injection of S-[ 18 F]FβOHB and time time-activity curves for untreated to treated brain and muscle over 60 min (n = 3–5 animals). (D) Parameters of the activity wheels measured after treatment with PSSI-51 or pimozide after to 24 and 48 after treatment ( n = 3 animals per group). (E) Mass spectrometric quantification of PSSI-51:pimozide ratio following a single dose of the drug ( n = 3 animals). Data are presented as mean ± SEM. Statistical analyses were conducted using Student’s t test or one-way ANOVA, supplemented by Bonferroni post hoc tests, with significance thresholds set at ∗ p < 0.05 vs. vehicle control, # p < 0.05 vs. pimozide.

Article Snippet: Plasma protein binding: Fresh blood collected from Sprague-Dawley rats was spiked with 1000 and 5000 ng/mL of PSSI-51 or pimozide.

Techniques: Inhibition, Activity Assay, Isolation, Injection, Control