Impacts of pregnancy and acute pyelonephritis on in vivo activity of organic anion transporters 1 and 3 employing furosemide pharmacokinetics

Author(s)

Jhohann Richard de Lima Benzi

• Document type: Doctoral Thesis
• Press: Ribeirão Preto.
• Institution: Universidade de São Paulo (USP). Faculdade de Ciências Farmacêuticas de Ribeirão Preto (PCARP/BC)
• Defense date: 2022-10-05

Examining board members

Vera Lucia Lanchote; Natalia Valadares de Moraes; Jorge Willian Leandro Nascimento; Silvia Regina Cavani Jorge Santos

• Advisor: Vera Lucia Lanchote

Abstract

Organic anion transporters (OAT) 1 and 3 are of fundamental importance in renal excretion and consequently in the drug dosage regimen. However, little is known about the influence of inflammation associated with kidney infection, especially in pregnant women, on the expression/activity of these transporters. Thus, this study developed protocols to investigate inflammation and pregnancy in the in vivo activity of OAT 1 and 3 employing furosemide (FUR) pharmacokinetics. In the first protocol, the impact of inflammation was investigated in pregnant women diagnosed with acute pyelonephritis (inflammation model), in the second and third trimesters of pregnancy. Patients were treated with intravenous cefuroxime (CER) 750 mg TID and received a single oral dose of FUR 40 mg before (n = 10) and 40 mg after (n = 7) the end of antibiotic treatment, hospital discharge and reduction of inflammation. Plasma cytokine concentrations were evaluated in the two phases of this protocol. Additionally, we sought to describe the pharmacokinetics and PK-PD relation of CER against 3 possible MIC for Escherichia coli (2, 4 and 8 µg/mL) in this population. The second protocol of this study investigated the impact of pregnancy in 10 healthy pregnant participants and 12 healthy non-pregnant participants who received a single oral dose of FUR 40 mg. In all groups and phases, serial blood and urine samples were collected up to 24h after FUR administration. Methods for the quantification of FUR, FUR glucuronide and CER in biological matrices were developed and validated in LC-MS/MS. The kinetic disposition of the FUR was evaluated by the non-compartmental model. The impact of inflammation (before and after CER treatment) on FUR pharmacokinetics was assessed by the Wilcoxon test, while the impact of pregnancy (pregnant and non-pregnant) was assessed by the Mann-Whitney test. The significance level was set at 5% for both tests. The bioanalytical methods showed adequate sensitivity and confidence limits for pharmacokinetic studies, allowing the quantification of FUR, FUR glucuronide and CER within 24 h after the administered doses. When compared to the post-infection/inflammation period, pregnant women diagnosed with acute pyelonephritis had plasma cytokine concentrations from 2 to 100-fold higher for MCP-1, TNF-α, IFN-γ, IL-6 and up to 10-fold for the C-reactive protein. In addition, they had higher median values (interquartile range) of Tmax 1.88 (1.38 - 4.52) h and lower values of CLR 4.08 (2.36 - 6.35) L/h and CLSEC 3.95 (2.29 - 6.21) L/h of FUR. Also, after the first dose of CER, pregnant patients had Cmax values: 43.0 (32.1 - 51.7) µg/mL, Tmax: 0.34 (0.29 - 0.46) h, AUC0-6: 66.7 (45.1 - 77.4) µg×h/mL, AUC0-∞: 66.7 (45.1 - 77.4) µg×h/mL, t1/2: 1.71 (1.32 - 1.82) h, CLss: 10.3 (8.65 - 15.6) L/h, Fe: 28.2 (13.2 - 43.6) %, CLR: 3.01 (2.41 - 4.24) L/h, Vdc: 24.2 (20.3 - 29.8) L, Vdss: 23.7 (19.4 - 26.6) L and Fu 0.67 (0.59 - 0.74). The CER treatment used was effective for 9 patients for MIC = 2 µg/mL, for 5 patients for MIC = 4 µg/mL and for no patient for MIC = 8 µg/mL. In the second protocol, healthy pregnant participants had lower AUC0-∞ 1110.48 (1033.88 - 1362.50) ng×h/mL, Ae 7.75 (5.67 - 10.04) mg and Fe 19.39 (14.50 - 25.11) %, as well as higher values of CL/F 38.17 (34.83 - 45.17) L/h and CLNR 31.64 (27.91 - 41.16) L/h when compared to healthy non-pregnant participants. Thus, we concluded that inflammation, assessed by acute pyelonephritis, reduced the in vivo activity of OAT 1 and 3 by approximately 50%. The PK-PD study suggests that a dose adjustment of at least 30% (total dose of approximately 1 g) would be sufficient for 8 of the 10 investigated patients to be effective (fT>MIC ≥ 50%) for MIC of 2 and 4 µg/mL. Finally, there was no impact of pregnancy on the in vivo activity of OAT 1 and 3. However, the increase of approximately 40% in CLNR and approximately 50% in CL/F in pregnant women suggests that another route of elimination and/or absorption may be altered in this condition. (AU)

• FAPESP's process: 19/03429-4 - Pyelonephritis impacts on Organic Anion Transporters (OAT) 1 and 3 activity in pregnant women: a quantitative system pharmacology approach
• Grantee: Jhohann Richard de Lima Benzi
• Support Opportunities: Scholarships in Brazil - Doctorate