Search

Preclinical evidence is needed to assess drug-metabolite behaviour in compromised liver function for developing the best antitubercular treatment (ATT) re-introduction regimen in drug-induced liver injury (DILI). The pharmacokinetic behavior of rifampicin (RMP) and its active metabolite des-acetyl-rifampicin (DARP) in DILI's presence is unknown. To study the pharmacokinetic behavior of RMP and DARP in the presence of carbon tetrachloride (CCl4) plus ATT-DILI in rats. Thirty rats used in the experiment were divided equally into six groups. We administered a single 0.5 mL/kg CCl4 intraperitoneal injection in all rats. Groups II, III, IV, and V were started on daily oral RMP alone, RMP plus isoniazid (INH), RMP plus pyrazinamide (PZA), and the three drugs INH, RMP, and PZA together, respectively, for 21-days subsequently. Pharmacokinetic (PK) sampling was performed at 0, 0.5, 1, 3, 6, 12, and 24 h post-dosing on day 20. We monitored LFT at baseline on days-1, 7, and 21 and sacrificed the rats on the last day of the experiment. ATT treatment sustained the CCl4-induced liver injury changes. A significant rise in mean total bilirubin levels was observed in groups administered rifampicin. The triple drug combination group demonstrated 1.43- and 1.84-times higher area-under-the-curve values of RMP (234.56±30.66 vs. 163.55±36.14 µg h/mL) and DARP (16.15±4.50 vs. 8.75±2.79 µg h/mL) compared to RMP alone group. Histological and oxidative stress changes supported underlying liver injury and PK alterations. RMP metabolism inhibition by PZA, more than isoniazid, was well preserved in the presence of underlying liver injury. [ABSTRACT FROM AUTHOR]

Background: We investigated the pharmacokinetic behavior of pyrazinamide (PZA) and pyrazinoic acid (PA) in the presence of carbon-tetrachloride (CCl4) plus antitubercular treatment (ATT) drug-induced liver injury (DILI) in rats. Methods: Thirty rats utilized in the experiment were separated equally into five groups. Each rat was injected with 0.5 ml/kg CCl4 intra-peritoneal injection on day zero. Group, I rats did receive only CCl4 (single i.p. injection, 0.5 ml/Kg in olive oil in a 1:1 ratio). Groups II, III, IV, and V did receive daily oral PZA, PZA plus isoniazid (INH), rifampicin (RMP) plus pyrazinamide (PZA), and three drugs together, respectively, for 21-days. Pharmacokinetic sampling was performed at 0, 0.5,1,3,6,12 and 24 hours post-dosing on day-20. Liver function test (LFT) was assessed at days 0,1,7, and 21 days after CCl4 and ATT administration, and rats were sacrificed on the last experiment day. Results: ATT treatment maintained the liver function changes initiated by CCl4 administration. An evidential LFT rise was observed in groups administered with pyrazinamide. Co-administration of Isoniazid caused a 2.02 and 1.78 times increase in Area-under-the-curve (AUC) values of PZA and PA, respectively (p < 0.05). Histological and oxidative-stress changes supported the biochemical and pharmacokinetic observations. Conclusion: The enzyme inhibitory capacity of isoniazid is well-preservd in CCl4-induced liver injury. [ABSTRACT FROM AUTHOR]

Background: N-acetyl transferase 2 (NAT2) polymorphism testing could not see the light of success as a biomarker tool in tuberculosis management. Additionally, the antitubercular treatment (ATT) drug's reintroduction regimen variations exist because of the scarcity of robust preclinical evidence on ATT drug metabolism. Objective: The experiment was planned to understand the pharmacokinetic (PK) behavior of isoniazid and acetylisoniazid (AcINH) in a Wistar rat model of acute liver injury induced by carbon tetrachloride (CCl4) and preclinical drug-induced liver injury (DILI) model induced with CCl4 + anti-Tuberculosis (TB) drugs together. Materials and Methods: Thirty rats were used for the experiment and were divided into five groups. All rats were administered a single 0.5 ml/kg CCl4 intraperitoneal injection on day 0 to induce an animal model of DILI. Group I rats received CCl4 alone. Groups II--V were started on additional gavage feedings of isoniazid (H) alone, H plus rifampicin (R), H plus pyrazinamide (Z), and H, R, and Z together, respectively, daily for 21 days subsequently. Isoniazid and AcINH PK assessment was accomplished on day 20 of continuous once-daily dosing. Liver function test (LFT) monitoring was done at baseline on days 1, 7, and 21. On the last day of experiments, all experimental rats were sacrificed. Results: Three-week ATT administration sustained the CCl4-induced LFT changes. Area under the curve (AUC) values for isoniazid and AcINH were found to be 2.24 and 1.69 times higher in the H + R group compared with the CCl4 + H group, respectively (P < 0.05). Isoniazid and AcINH maximum concentration (Cmax) reached the highest, while isoniazid clearance reached the lowest in the H + R group. AcINH AUC increased by double in the CCl4 + Isoniazid+Rifampicin +Pyrazinamide (HRZ) group compared with the CCl4 + H group (P < 0.05). Biochemical, histological, and antioxidant changes were consistent with the new liver injury model's development. Conclusion: Rifampicin almost doubles up the isoniazid and AcINH exposure, in presence if DILI. [ABSTRACT FROM AUTHOR]

Pharmacokinetics of cyclophosphamide has been explored to optimize conditioning dosing. We hypothesized that post-transplant cyclophosphamide (PTCy) metabolite carboxy-ethyl phosphoramide mustard (CEPM) pharmacokinetics might impact haploidentical transplantation (haplo-HCT) outcomes. CEPM area under the curve (AUC0–48) was determined by eleven sampling timepoints on day +3/+4 using LC-MS/MS. The median CEPM AUC0–48 in a cohort of 30 patients was 14.2 (14) mg·hr/L. The incidence of severe chronic graft-versus-host disease (GVHD) (73% vs. 11%, p = 0.02), and GVHD-/relapse-free survival (GRFS) was significantly inferior in the CEPM AUC0–48 < 14 mg·hr/L group (54 days vs. 344 days, p = 0.02). There was, however, no difference in grade III-IV acute GVHD (38% vs. 14%, p = 0.12) and overall survival (295 days vs. not reached, p = 0.2). CEPM AUC0–48, is associated with severe chronic GVHD and GRFS post-haplo-HCT in this exploratory study. There is scope for personalizing day + 4 PTCy dose based on day + 3 CEPM AUC0–8. [ABSTRACT FROM AUTHOR]

The putative hypolipidemic properties of scopoletin have not been fully confirmed due to a lack of validation in an irreversible chronic hyperlipidemia animal model. The druggability also needs to be studied in terms of bioavailability in the vascular compartment. Accordingly, we conducted a study to assess the hypolipidemic and pharmacokinetic behavior of scopoletin in the high-fructose high-fat diet (HFHFD)-induced dyslipidemia model in Wistar rats. A total of 42 rats were studied, with 6 in each of the 7 groups. A 60-day HFHFD opted for induction of dyslipidemia. Group I and groups II–VII received normal rat chow diet and HFHFD, respectively. Oral scopoletin (1, 5, 10 mg/kg) and atorvastatin 5 mg/kg were administered in groups III–VI, respectively, once daily for the next 15 days. A separate group, group VII, was used for the pharmacokinetic assessment comparing the scopoletin 10 mg/kg intraperitoneally (IP) in group VII versus the oral (group V). Pharmacokinetic blood sampling was performed on the 10th day of continuous once-daily therapy. Rats were sacrificed for the histological examination. All three scopoletin dosages significantly decreased the total cholesterol, low-density lipoproteins, and triglycerides (P < .05 for all), but not in a dose-dependent manner. Atherogenic Index of plasma, Castelli's risk indices, and histopathological findings confirmed the protective effect of scopoletin. The IP administration showed a 23.18% higher exposure than the oral route (P < .001 for area under the curve and P < .05 for concentration-maximum). This study confirms the hypolipidemic efficacy of scopoletin in a more robust irreversible model of dyslipidemia. Scopoletin's gut absorption in the disease state may also boost the initial phase exploratory clinical trial. [ABSTRACT FROM AUTHOR]