骨髓间充质干细胞移植治疗重症急性胰腺炎肺损伤

Transplantation of bone marrow mesenchymal stem cells in the treatment of severe acute pancreatitis-associated lung injury

BACKGROUND:A large number of studies have confirmed that bone marrow mesenchymal stem cells can couple with the circulation of the blood to other organs, promote pancreatic tissue repair injury and reduce pulmonary fibrosis, which have certain therapeutic effects on pancreas and lung injuries. OBJECTIVE:To study the therapeutic effect on severe acute pancreatitis-associated lung injury in rats after the transplantation of bone marrow mesenchymal stem cells. METHODS:Animal models of severe acute pancreatitis-associated lung injury were prepared in rats via retrograde injection of 4% sodium taurocholate. Sprague-Dawley rats were randomized into three groups and received bone marrow mesencnymal stem cell injection via the tail vein in transplantation group, the same volume of normal saline in control group, or no treatment in normal groups. All the treatments in each group were performed 24 hours after modeling. Twenty-four hours after transplantation, hematoxylin-eosin staining of the pancreatic and lung tissues was performed. mRNA expressions of tumor necrosis factor-α and interleukin-1β in pancreatic and lung tissues were detected. ELISA kit was used to detect levels of serum C-reactive protein and tumor necrosis factor-α. RESULTS AND CONCLUSION:After modeling, under hematoxylin-eosin staining, there were a large number of inflammatory cells infiltrating in the damaged pancreatic tissues, accompanied by incomplete acinar structures, seriously destroyed lobular structures, alveolar fusion in the lung tissues, thickening of the alveolar walls, and a large amount of inflammatory cells infiltrating in the alveoli. These findings indicated successful modeling of severe acute pancreatitis-associated lung injury in rats. After cell transplantation, the number of infiltrated inflammatory cells in the damaged pancreatic tissue was reduced, with clear lobular structures and no bleeding from the acini; the structure of lung tissues was clear, with complete alveolar walls, and the width of alveolar space was reduced. Immunohistochemical results showed that transplanted DAPI-labeled bone marrow mesenchymal stem cells were aggregated in the pancreas and lung tissue, and uneven distributed in the damaged area. No DAPI expression in the pancreas and lung tissue was found in the control group, indicating transplanted bone marrow mesenchymal stem cells migrated into the damaged pancreas and lung tissue through the blood circulation, to further repair the damage area. RT-PCR test results showed that compared with the control group, bone marrow mesenchymal stem cell transplantation significantly reduced the levels of tumor necrosis factor-α and interleukin-1β in the pancreatic and lung tissues (P < 0.05). Higher levels of C-reactive protein and tumor necrosis factor-α were found in the control group compared with the normal group (P < 0.01), while the lower levels were obtained in the control group (P < 0.05). To conclude, our findings suggest that bone marrow mesenchymal stem cell transplantation is an effective therapy for severe acute pancreatitis-associated lung injury, and its mechanism may be associated with the reduction of inflammatory reactions and translation into the pancreas and lung tissue.