Protective effects of a heme oxygenase-1-secreting Lactococcus lactis on mucosal injury induced by hemorrhagic shock in rats.
OBJECTIVE
To investigate the protective effects of a heme oxygenase-1 (HO-1)-secreting Lactococcus lactis (LL-HO-1) on mucosal injury induced by hemorrhagic shock in rats.


METHODS
The ability of recombinant LL-HO-1 to secrete biological active HO-1 in the rat intestine was determined in situ after 3 d of daily intragastric administration. The therapeutic potential of LL-HO-1 strain was then evaluated on mucosal injury induced by hemorrhagic shock in rats. After successful resuscitation, mean arterial blood pressure was recorded at 5, 10, 20, and 30 min. One hour after resuscitation, the ileum was harvested for evaluation of mucosal injury by blinded microscopic inflammatory score (Chiu's grade 0-5), myeloperoxidase activity, bacterial translocation, and by the secretion of pro- and anti-inflammatory cytokines (tumor necrosis factor-alpha and interleukin-10, respectively).


RESULTS
Intragastric administration of HO-1-secreting L. lactis strain led to bioactive delivery of HO-1 at intestinal mucosa and significantly enhanced mean arterial blood pressure and interleukin-10 levels. Moreover, intragastric administration of LL-HO-1 significantly decreased Chiu's score, myeloperoxidase activity, bacterial translocation, and tumor necrosis factor-alpha levels when compared with rats treated with the wild-type strain. The protective effect of recombinant LL-HO-1 could be abolished by co-administration of a HO-1 inhibitor, the zinc protoporphyrin-IX.


CONCLUSIONS
These results suggest that intragastric administration with HO-1-secreting L. lactis reduces mucosal injury induced by hemorrhagic shock.
Pang
Qing-feng
QF
Department of Pharmacology, Nanjing Medical University, Nanjing, Jiangsu Province, People's Republic of China.
Ji
Yong
Y
Bermúdez-Humarán
Luis G
LG
Zhou
Qiao-mei
QM
Hu
Gang
G
Zeng
Yinming
Y
D000818:Animals; D004195:Disease Models, Animal; D051547:Heme Oxygenase-1 / Q000096:biosynthesis*; D007082:Ileum; D007413:Intestinal Mucosa / Q000378:metabolism* / Q000382:microbiology; D013294:Lactococcus lactis / Q000378:metabolism*; D019936:Probiotics / Q000378:metabolism*; D051381:Rats; D012771:Shock, Hemorrhagic / Q000150:complications*
D051547:Heme Oxygenase-1