Characterization of Toxicological Properties of L-Lysine Polymers in CD-1 Mice

Abstract

We recently showed that polylysine, the polymer of lysines, retains anti-prion activity. Although the effectiveness of prion inhibition by polylysine was demonstrated with the regimen tolerated in mice, a determination of quantitative polylysine toxicity is necessary to precisely address the in vivo toxicity level of polylysine. In this communication, we report the results of body weight monitoring and hematologic tests performed in CD-1 mice that received two different tolerable dosages of polylysine for an either 5-day or 4-week period. We found that there was no significant alteration in overall serum chemistry, blood cell count, and body weight gain compared with controls. The only notable quantitative change with statistical significance was the decrease of platelet numbers in mice subchronically administered with polylysine. Our results suggest that polylysine is harmless in mice if administered for a short period, but administrations of polylysine in mice may require considerate attention for safety in future investigations as mice chronically receive tolerable doses of polylysine.

Polymersomes from Polypeptide Containing Triblock Co- and Terpolymers for Drug Delivery against Pancreatic Cancer: Asymmetry of the External Hydrophilic Blocks

“…Empty polymersomes were further tested for toxicity against NOD/SCID mice. Polylysine is regarded in general as a toxic substance . It is reported that toxicity of polylysine is even dependent on the administration route.…”

“…12 mg kg −1 ) when a single intravenous dose of polylysine with identical molecular masses was given to mice . However Titlow et al reported that polylysine is harmless in mice if administered for a short period. In their study they only observed a transient hypoactivity (sedation) when 8 mg kg −1 of polylysine was administered intraperitoneally for a period of 5 days (a total dose of 40 mg kg −1 ).…”

“…Polylysine is regarded in general as a toxic substance. [51] It is reported that toxicity of polylysine is even dependent on the administration route. The half maximal lethal dose (LD50) was determined as 45 mg kg À1 Á d À1 ), when polylysine of an average molecular mass of 50 kDa was injected intraperitoneally once a day for 5 days in mice (a total dose of 250 mg kg À1 ).…”

BMD42-2910, a Novel Benzoxazole Derivative, Shows a Potent Anti-prion Activity and Prolongs the Mean Survival in an Animal Model of Prion Disease

“…The compounds were daily administered intraperitoneally using a 1-mL syringe and a 26-gauge, 1.27-to 2.54-cm (1/2 to 1 inch) needle with a short bevel for 7 days. The injection was made in the lateral aspect of the lower left quadrant [31,32]. The volume injected into each mouse was 10 mL/kg.…”

In‐vitro toxicity of carbon nanotube/polylysine colloids to colon cancer cells

“…Artificial methods for pLlys synthesis typically yield α-pLlys, since the polymerisation occurs through the α-amino group, and can reach much higher molecular weights than natural ɛ-pLlys. Synthetic pLlys is utilised as an adhesion promoter in cell cultures, and it is being investigated for its antineoplastic activity, anti-prion activity, and gene delivery properties [3][4][5].…”