Recombinant human lactoferrin has a potential to suppresses uterine cervical ripening in preterm delivery in animal model.
OBJECTIVE
To investigate the effect of recombinant human lactoferrin (rhLF) on cervical ripening using a rabbit model in which preterm labor was induced by bacterial endotoxin lipopolysaccharide (LPS).


METHODS
Timed pregnant rabbits (New Zealand White, 3-4 kg, day 14) were randomly assigned to the following treatment groups: Group A, LPS + rhLF (n = 4); Group B, LPS (n = 4); and Group C, control (n = 4). Recombinant human lactoferrin (10 microg) was administrated to pregnant rabbits in Group A and not in Group B. Lipopolysaccharide (100 microg) was given to the rabbits in both groups for 3 days (days14-16). Drugs were administered as a vaginal suppository. On day 18, the rabbits were anesthetized with intramuscular ketamine hydrochloride (20 mg/kg) and diazepam (4 mg/kg). Both cervices of the rabbit uterus, which is bicorpus-bicolli, were taken out. One cervix was placed in 10% formalin solution for a histological study with standard hematoxylin-eosin staining. The other was used for an extension test to assess the grade of ripening. Extension was measured after a 5-mm length of cervical tissue was loaded with 5.8 g.


RESULTS
The histological study showed remarkably loose and edematous connective tissue in Group B cervices. Cervical tissues in Group A was not different from those in Group C. Extension lengths were 2.2 +/- 0.2 mm in Group A, 7.0 +/- 2.7 mm in Group B, and 1.7 +/- 0.3 mm in Group C.


CONCLUSIONS
These results suggest that rhLF inhibits cervical maturation induced by LPS in a rabbit model and may have a potential to prevent preterm delivery caused by cervical infection and ripening.
Yakuwa
K
K
Department of Obstetrics and Gynecology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8666, Japan.
Otsuki
K
K
Nakayama
K
K
Hasegawa
A
A
Sawada
M
M
Mitsukawa
K
K
Chiba
H
H
Nagatsuka
M
M
Okai
T
T
D000282:Administration, Intravaginal; D000818:Animals; D020070:Cervical Ripening / Q000187:drug effects*; D002584:Cervix Uteri / Q000187:drug effects / Q000473:pathology; D005260:Female; D006801:Humans; D007781:Lactoferrin / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D023421:Models, Animal; D011247:Pregnancy; D047928:Premature Birth / Q000517:prevention & control*; D011817:Rabbits; D011897:Random Allocation; D011994:Recombinant Proteins / Q000494:pharmacology*
D008070:Lipopolysaccharides; D011994:Recombinant Proteins; D007781:Lactoferrin