Mouse erythrocytes as carriers for coencapsulated alcohol and aldehyde dehydrogenase obtained by electroporation - In vivo survival rate in circulation, organ distribution and ethanol degradation
C. Lizano et al., Mouse erythrocytes as carriers for coencapsulated alcohol and aldehyde dehydrogenase obtained by electroporation - In vivo survival rate in circulation, organ distribution and ethanol degradation, LIFE SCI, 68(17), 2001, pp. 2001-2016
Alcohol dehydrogenase and aldehyde dehydrogenase (ADH and ALDH) have been c
oencapsulated into mouse erythrocytes by an electroporation technique. The
optimal conditions were achieved as follows: 420 V, four pulses of 1 ms eve
ry 15 min. at 37 degreesC, completed by resealing: 1 h at 37 degreesC. An e
ncapsulation yield ranging from 11-12% was obtained for ADH + ALDH-loaded e
rythrocytes. Carrier cell recovery was 52%. Electroporated-RBCs observed un
der Scanning electron microscopy exhibited a tendency toward invaginated sp
hero-stomatocytes. These invaginations were not found in electroporated/res
ealed RBCs, The intravenous administration of Cr-51-RBCs manifested a bimod
al pharmacokinetic profile: an initial phase (t(1/2 alpha)) with a rapid de
crease of plasma Cr-51-RBCs followed by a slow and prolonged elimination ph
ase (t(1/2 beta)), The values corresponding to in vivo survival rate during
the elimination phase indicated that the survival rate of Cr-51-electropor
ated loaded-RBCs was slightly lower (t(1/2 beta), 4.5 days) than Cr-51-nati
ve RBCs (t(1/2 beta), 5.3 days). The mean clearance values from blood of el
ectroporated Cr-51-RBCs (unloaded and loaded) were higher (0.51 %Cr-51/day
and 0.54 %Cr-51/day, respectively) than the obtained for native Cr-51-RBCs
(0.18 % Cr-51/day). The target organs for electroporated RBCs proved to be
the same as for native RBCs. However, electroporated RBCs showed highest ac
cumulation in liver, spleen and lung, since they were promptly recognized b
y the reticuloendothelium system. Mice induced to the state of acute ethano
l intoxication and treated with ADH + ALDH-RBCs clearly showed a lower leve
l of ethanol concentration in plasma (less than 43% ethanol) than the intox
icated mice treated with native RBCs. En consequence the clearance values o
f ethanol from blood in intoxicated mice treated with ADH + ALDH-RBCs (0.39
ml/min) were higher than the treated with native RBCs (0.20 ml/min). The r
esults obtained suggest that ADH + ALDH-loaded erythrocytes could be used a
s a potential carrier system for in vivo removal of high levels of ethanol
from blood caused by excessive alcohol consumption. (C) 2001 Elsevier Scien
ce inc. All rights reserved.