【Objective】 To investigate the effect and mechanism of curcumin on lung inflammatory injury induced by one-lung ventilation (OLV) in a rabbit model of thoracic surgery. 【Methods】 Twelve New Zealand rabbits weighing 2.0~2.5 kg were randomly allocated into two groups (n = 6 each): OLV+placebo group (group 1) received 10% dimethyl sulfoxide (DMSO) as placebo and OLV+curcumin group (group 2) received curcumin 40 mg/kg which dissolved in 10% DMSO by intraperitoneal injection. After seven consecutive days of pretreatment

the animals were received orotracheal intubation and the model of OLV-induced lung injury in thoracic surgery was established. Then two groups were received mechanical ventilation (VT = 12 mL/kg

RR = 40 bpm

I:E = 1:2

FiO2 = 0.6). After two lung ventilation (TLV) for 30 min

they received OLV for 3 h

and then turned to TLV for 30 min. Monitoring blood pressure

heart rate and peak inspiratory pressure of animals in two groups continuously

and collecting arterial blood samples to calculate the PaO2/FiO2 ratio (P/F ratio) before (T0) and after (T4) mechanical ventilation

respectively. At the end of the experiment

the animals were killed and abronchoalveolar lavage was performed in the right lung lobes for the concentration of MPO and neutrophil counts. The left lobes were collected for HE stain to observe pathological morphological changes and get lung injury score. Then the concentration of IL-8

IL-10

IL-1β

TNF-α

and MIP-1 (macrophage inflammatory protein-1) in two lungs were quantified using enzyme-linked immunosorbent assay (ELISA). Furthermore

the levels of nuclear factor kappa B (NF-κB)

myeloid differentiation factor 88 (MyD88) and Toll-like receptor 2 (TLR2) were analyzed by immunohistochemistry.【Results】 The P/F ratio in group 2 was significantly higher than that in group 1 at T4 (P < 0.05). Compared with group 1

the concentration of MPO and neutrophil counts in BALF

lung injury score

the contents of IL-8

IL-1β

TNF-α

and MIP-1 in group 2 were significantly lower (P < 0.05)

the level of IL-10 in group 2 was significantly higher (P < 0.05). In group 1

compared with the right (ventilated) lung

MPO concentration in BALF

neutrophil counts

lung injury score and the contents of IL-8

IL-1β

TNF-α

and MIP-1 in the left (nonventilated) lung were significantly higher(P < 0.05)

and the contents of IL-10 in the left lung were lower (P < 0.05). The expression of NF-κB

MyD88

and TLR2 in the group 2 were much lower than those in the group 1 (P < 0.05). 【Conclusion】Curcumin pretreatment attenuates inflammatory injury induced by one lung ventilation of rabbits in thoracic surgery

and the anti-inflammatory effect of curcumin is possibly related to the inhibition of TLR2

MyD88

and NF-κB.