Renal Disposition Characteristics of Oligonucleotides Modified at Terminal Linkages in the Perfused Rat Kidney

Abstract

To clarify the renal disposition characteristics of oligonucleotides at the organ level, the renal handling of model end-capped oligonucleotides, 3'-methoxyethylamine 5'-biotin-decathymidylic acid containing phosphoramidate modifications at 3'- and 5'-terminal internucleoside linkages (T10) and its phosphorothioate (Ts10), were studied in the perfused rat kidney. In a single-pass indicator dilution experiment, venous outflow and urinary excretion patterns and tissue accumulation of radiolabeled oligonucleotides were evaluated under filtering or nonfiltering conditions. No significant binding to bovine serum albumin (BSA) in the perfusate was observed for T10, whereas more than 90% of Ts10 bound to BSA. The steady-state distribution volume of T10 calculated from the venous outflow pattern was larger than that of inulin, which corresponds to the extracellular volume of the kidney, whereas the distribution volume of Ts10 was larger than that of BSA (the intravascular volume). These results suggested their interaction with the vascular wall. Rapid urinary excretion was observed for T10, similar to inulin used as a marker of golmerular filtration rate. On the other hand, urinary excretion of Ts10 was greatly restricted due to its high binding ability (> 90%) to BSA in the perfusate. A significant amount of T10 and Ts10 was accumulated in the kidney (T10, 1.8% of injected dose; Ts10, 1.3%) compared with inulin (0.2%) and BSA (< 0.1%). The accumulation of these oligonucleotides was ascribed to both tubular reabsorption and uptake from the capillary side. In addition, the uptake of T10 from the capillary side was significantly inhibited by simultaneous injection of dextran sulfate, suggesting that the oligonucleotide was taken up as an anionic molecule. These findings will be useful information for the development of delivery systems for antisense oligonucleotides.

Nanogels for Oligonucleotide Delivery to the Brain

“…Encapsulation of ODN in nanogels may have protective effect reducing the nonspecific interactions. It could also decrease the renal clearance of ODN because the molecular mass of nanogel-ODN complexes exceeds the renal clearance threshold (38). However, to fully address this issue, further studies of the in vivo properties of nanogel carriers need to be done.…”

Specific uptake of plasmid DNA without reporter gene expression in Atlantic salmon (Salmo salar L.) kidney after intramuscular administration

“…The [ 125 I]fluorescein alone has been shown not to be recognised or taken up by a receptor-specific mechanism [37]. This molecule will undergo glomerular filtration, along with oligonucleotides [40,41] and macromolecules with a molecular weight of 30 kDa (1 bp z 0.6 kDa) or less [42e44]. Redistribution of macromolecules from the administration site has previously been described in Atlantic cod after subcutaneous administration of a connective tissue molecule, hyaluronan [37], although redistribution of DNA is not well studied in fish.…”

What happens to the DNA vaccine in fish? A review of current knowledge

“…A rapid clearance of supercoiled pDNA from the circulation is observed [173], with a serum half-life varying between 1e20 min [165,174e177], depending on the pDNA topoform and analytical method used. Plasmid DNA fragments [178,179] in the blood with a molecular weight of 30 kDa (1 bp z 0.6 kDa) or less may be eliminated from the circulation by glomerular filtration [180]. The tissue distribution of pDNA after i.v.…”