Preventive effects of curcumin and dexamethasone on lung transplantation-associated lung injury in rats

Objective: To investigate potential effects of curcumin or dexamethasone on lung transplantation-associated lung injury. Design: Prospective, randomized, controlled study. Setting: Research laboratory. Subjects: Adult male Sprague-Dawley rats. Interventions: Sham-operated rats were used as time-matched controls. Experimental rats were subjected to unilateral orthotopic lung transplantation with 4 hrs of cold ischemia followed by 2 hrs (or 24 hrs) of reperfusion. Animals were randomly assigned to vehicle-, curcumin-, or dexamethasone-treated groups. Measurements and Main Results: Transplantation-associated lung injury was characterized by an increased alveolar-capillary permeability and myeloperoxidase activity and decreased levels of arterial oxygen tension/inspired oxygen concentration ratio. Pretreatment with curcumin and dexamethasone significantly prevented barrier disruption, lung edema, tissue inflammation, and decreased PaO2 at the early stage of posttransplantation. Nuclear factor-kappa B in transplanted lungs was activated, accompanied by an increase in messenger RNA levels and protein content of tumor necrosis factor-alpha, interleukin-6, and matrix metalloproteinase-9 in lung graft. Those changes were prevented by pretreatment with curcumin and dexamethasone. Conclusions. Curcumin can be an alternative therapy for protecting lung transplantation-associated injury by suppressing nuclear factor-kappa B- mediated expression of inflammatory genes.