Background: Acute lung injury (ALI) is a common complication of sepsis that is associated with high mortality, lntracellular Ca^2+ overload plays an important role in the pathophysiology of sepsis-induced ALl, and...Background: Acute lung injury (ALI) is a common complication of sepsis that is associated with high mortality, lntracellular Ca^2+ overload plays an important role in the pathophysiology of sepsis-induced ALl, and cyclic adenosine diphosphate ribose (cADPR) is an important regulator of intracellular Ca^2+ mobilization. The cluster of differentiation 38 (CD38)/cADPR pathway has been found to play roles in multiple inflammatory processes but its role in sepsis-induced ALl is still unknown. This study aimed to investigate whether the CD38/cADPR signaling pathway is activated in sepsis-induced ALl and whether blocking cADPR-mediated calcium overload attenuates ALl. Methods: Septic rat models were established by cecal ligation and puncture (CLP). Rats were divided into the sham group, the CLP group, and the CLP+ 8-bromo-cyclic adenosine diphosphate ribose (8-Br-cADPR) group. Nicotinamide adenine dinucleotide (NAD+), cADPR, CD38, and intracellular Ca^2+ levels in the lung tissues were measured at 6, 12, 24, and 48 h after CLP surgery. Lung histologic injury, tumor necrosis factor (TNF)-a, malondialdehyde (MDA) levels, and superoxide dismutase (SOD) activities were measured. Results: NAD+, cADPR, CD38, and intracellular Ca-+ levels in the lungs of septic rats increased significantly at 24 h after CLP surgery. Treatment with 8-Br-cADPR, a specific inhibitor of cADPR, significantly reduced intracellular Ca^2+ levels (P = 0.007), attenuated lung histological injury (P = 0.023), reduced TNF-a and MDA levels (P 〈 0.001 and P = 0.002, respectively) and recovered SOD activity (P = 0.031) in the lungs of septic rats. Conclusions: The CD38/cADPR pathway is activated in the lungs of septic rats, and blocking cADPR-mediated calcium overload with 8-Br-cADPR protects against sepsis-induced ALl.展开更多
文摘Background: Acute lung injury (ALI) is a common complication of sepsis that is associated with high mortality, lntracellular Ca^2+ overload plays an important role in the pathophysiology of sepsis-induced ALl, and cyclic adenosine diphosphate ribose (cADPR) is an important regulator of intracellular Ca^2+ mobilization. The cluster of differentiation 38 (CD38)/cADPR pathway has been found to play roles in multiple inflammatory processes but its role in sepsis-induced ALl is still unknown. This study aimed to investigate whether the CD38/cADPR signaling pathway is activated in sepsis-induced ALl and whether blocking cADPR-mediated calcium overload attenuates ALl. Methods: Septic rat models were established by cecal ligation and puncture (CLP). Rats were divided into the sham group, the CLP group, and the CLP+ 8-bromo-cyclic adenosine diphosphate ribose (8-Br-cADPR) group. Nicotinamide adenine dinucleotide (NAD+), cADPR, CD38, and intracellular Ca^2+ levels in the lung tissues were measured at 6, 12, 24, and 48 h after CLP surgery. Lung histologic injury, tumor necrosis factor (TNF)-a, malondialdehyde (MDA) levels, and superoxide dismutase (SOD) activities were measured. Results: NAD+, cADPR, CD38, and intracellular Ca-+ levels in the lungs of septic rats increased significantly at 24 h after CLP surgery. Treatment with 8-Br-cADPR, a specific inhibitor of cADPR, significantly reduced intracellular Ca^2+ levels (P = 0.007), attenuated lung histological injury (P = 0.023), reduced TNF-a and MDA levels (P 〈 0.001 and P = 0.002, respectively) and recovered SOD activity (P = 0.031) in the lungs of septic rats. Conclusions: The CD38/cADPR pathway is activated in the lungs of septic rats, and blocking cADPR-mediated calcium overload with 8-Br-cADPR protects against sepsis-induced ALl.