Figure 4.

The Effect on ALA/PBG Excretion of the Hit Compound and Analog in Hmbs-Deficient Mice

Three groups of Hmbs-deficient T1/T2^−/− mice (n = 6 in each group) were treated for 12 days with 20 mg/kg/day of C5, C6, or the analog C6-3, given orally. I.p. injection of phenobarbital was given on days 10–12 to induce the heme biosynthesis and thus, precipitation of biochemical acute attack. The control group was given 10% DMSO and likewise induced with phenobarbital. Urine was collected on days 1 and 10–12, and livers were harvested after sacrifice. (A and B) Bars represent porphyrin precursors ALA (A) and PBG (B) from C5 (red), C6 (blue), and C6-3 (green) treatment, measured in the urine (u) pooled for all mice from each group. The control group is shown in white. (C) HMBS protein levels measured in liver lysates by western blot quantification. Scatterplots with mean representing HMBS protein levels in mice livers treated with C5 (red), C6 (blue), and C6-3 (green). *p < 0.05 for differences with the corresponding control (10% DMSO without compound; white circles), calculated by unpaired two-tailed t test. Data are presented as mean ± SD. (D) HMBS activity in liver lysates. Scatterplot with mean showing the hepatic HMBS activity after treatment with C6 (blue) and C6-3 (green). **p < 0.01 and ****p < 0.0001 for differences with the corresponding control (10% DMSO without compound; white circles), calculated by unpaired two-tailed t test. Data are presented as mean ± SD. (E and F) The relative concentrations of ALA (E) and PBG (F) were measured in liver tissue extracts after treatment with C6 (blue) and C6-3 (green). *p < 0.05 for differences with the corresponding control (10% DMSO without compound; white), calculated by unpaired two-tailed t test. Data are presented as mean ± SD.