Comparison of oximes K203 and K027 based on Benchmark dose analysis of rat diaphragmal acetylcholinesterase reactivation

BODIPY-labelled acetylcholinesterase reactivators can be encapsulated into ferritin nanovehicles for enhanced bioavailability in the CNS

The BODIPY-labelled oxime reactivator was prepared and used to study its biodistribution into central nervous system. The newly synthesized oxime was found to be weak inhibitor of acetylcholinesterase and strong inhibitor of butyrylcholinesterase. Its reactivation ability for organophosphate inhibited acetylcholinesterase was found similar to a parent oxime. The BODIPY-labelled oxime was further encapsulated into recombinant human H-ferritin and evaluated in vitro and in vivo. The oxime or encapsulated oxime were found to be bioaccumulated primarily in liver and kidneys of mice, but some amount was distributed also to the brain, where it was detectable even after 24 h. The BODIPY-labelled oxime encapsulated to human H-ferritin showed better CNS bioaccumulation and tissue retention at 8 and 24 h time points compared to free oxime, although the fluorescence results might be biased due to BODIPY metabolites identified in tissue homogenates. Taken together, the study demonstrates the first utilization of recombinant ferritins for changing the unfavourable pharmacokinetics of oxime reactivators and brings promising results for follow-up studies.

Oxidative stress, metallomics and blood toxicity after subacute low-level lead exposure in Wistar rats: Benchmark dose analyses

Exposure to lead (Pb) is still rising concern worldwide, having in mind that even low-dose exposure can induce various harmful effects. Thus, in-depth knowledge of the targets of Pb toxicity and corresponding mechanisms is essential. In the presented study, the six groups (male Wistar rats, n = 6) received 0.1; 0.5; 1; 3; 7; 15 mg Pb/kg body weight/day for 28 days, each day by oral gavage, while the control group received distilled water only. All animals were sacrificed 24 h after the treatment, and blood was collected for the analysis of hematological, biochemical, oxidative status and essential elements levels. An external and internal dose-response relationship was performed using PROASTweb 70.1 software. The results showed that low doses of Pb affect hematological parameters and lipid profile after 28 days. The possible mechanisms at examined Pb dose levels were a decrease in SOD, O₂^•- and Cu and an increase in Zn levels. The dose-dependent nature of changes in cholesterol, HDL cholesterol, O₂^.-, SOD, AOPP in serum and hemoglobin, Fe, Zn, Cu in blood were obtained in this study. The most sensitive parameters that were alerted are Cu blood levels (BMDL₅: 1.4 ng/kg b.w./day) and SOD activity (BMDL₅: 0.5 μg/kg b.w./day). The presented results provide information that may be useful in further assessing the health risks of low-level Pb exposure.