Intimal hyperplasia(IH)is a negative vascular remodeling after arterial injury.IH occasionally occurs in elastase-induced abdominal aortic aneurysm(AAA)mouse models.This study aims to clarify the incidence and histolo...Intimal hyperplasia(IH)is a negative vascular remodeling after arterial injury.IH occasionally occurs in elastase-induced abdominal aortic aneurysm(AAA)mouse models.This study aims to clarify the incidence and histological characteristics of IH in aneurysmal mice.A retrospective study was conducted by including 42 male elastaseinduced mouse AAA models.The IH incidence,aortic diameters with or without IH,and hyperplasia lesional features of mice were analyzed.Among 42 elastase-induced AAA mouse models,10 mice developed mild IH(24%)and severe IH was found in only 2 mice(5%).The outer diameters of the AAA segments in mice with and without IH did not show significant difference.Both mild and severe IH lesions show strong smooth muscle cell positive staining,but endothelial cells were occasionally observed in severe IH lesions.There was obvious macrophage infiltration in the IH lesions of the AAA mouse models,especially in mice with severe IH.However,only a lower numbers of T cells and B cells were found in the IH lesion.Local cell-secreted matrix metalloproteinases(MMP)2 was highly expressed in all IH lesions,but MMP9 was only overexpressed in severe lesions.In conclusion,this study is the first to demonstrate the occurrence of aneurysmal IH and its histological characteristics in an elastaseinduced mouse AAA model.This will help researchers better understand this model,and optimize it for use in AAA-related research.展开更多
Background The pathological characteristics of abdominal aortic aneurysm （AAA） involved the regression of extracellular matrix （ECM） in aortic walls, especially elastic structure in medial layer. As the major stru...Background The pathological characteristics of abdominal aortic aneurysm （AAA） involved the regression of extracellular matrix （ECM） in aortic walls, especially elastic structure in medial layer. As the major structural protein of aorta, elastin contributes to the extensibility and elastic recoil of the vessels. We hypothesized that overexpression of elastin in vessel walls might regenerate the elastic structure of ECM, restore the elastic structure of the aneurysmal wall, and eventually lead to a reduction of aortic diameters （ADs） in an experimental model of AAA. Methods Tropoelastin （TE） of Sprague Dawley （SD） rat was synthesized by reverse transcription polymerase chain reaction and used to construct adneviral vectors containing elastin precursor protein （AdTE-GFP）. Cultured vascular smooth muscle cells （VSMCs） from aortas of male SD rats were transfected with AdTE-GFP, AdGFP, adenoviral vector （AdNull）, and phosphate buffered saline （PBS）. Immunofluorescence staining was performed to determine the expression of elastin in transfected cells. The expression of elastic fibers in ECM of VSMCs transfected with AdTE-GFP were detected by fluorescence microscopy and transmission electron microscopy （TEM） at 1, 3, and 5 days following gene transfer. The AAA vessel walls were infused with AdTE-GFP or an empty AdNull, or PBS directly into the aneurysmal lumen. ADs of the aneurysms were compared in infused aortas. Formation of new elastic fibers in vivo was assessed by hematoxylin and eosin, and elastic von-Giesson staining. Recombinant elastin-GFP in vivo was identified by immunohistochemical staining. Results Elastic fibers were increased both in ECM of VSMC and in vessel walls after gene transfer. Histological studies revealed that the AdTE-GFP-transduced aortas had elastic fiber regeneration in the aneurysmal walls. The AdTE-GFP-transduced aortas showed a decreased AD （23.04%±14.49%, P 〈0.01） in AAA vessel walls. Conclusions Elastic fibers have been successfully overexpressed both in vitro and in a rat model of AAA by a technique of gene transfer. The overexpression of elastic fibers within the aneurysmal tissue appeared to reverse the aneurysm dilatation in this model.展开更多
To provide experimental model for abdominal aortic aneurysm research and to optimize design of stent-graft,the authors established an animal models of prosthetic abdominal aortic aneurysm (PAAA) in dogs,evaluated its ...To provide experimental model for abdominal aortic aneurysm research and to optimize design of stent-graft,the authors established an animal models of prosthetic abdominal aortic aneurysm (PAAA) in dogs,evaluated its biofunction,biocompatibility and renal effect.The PAAA was sutured using aneurysm neck (Φ 6 mm artificial blood vessel) and aneurysm body (Φ 29 and 31mm artificial blood vessel,respectively). Sixteen healthy adult dogs,with weight of 13. 5 ± 0. 66 kg,were randomly divided into 2 groups: group 29 mm and group 31 mm,8 in each group. Infrarenal aortic artery was reconstructed with PAAA to establish abdominal aortic aneurysm (AAA) animal model. Blood coagulation index such as prothrombin time (PT),activated partial thromboplatin time (APTT),thrombin time (TT) and Fibrinogen (Fbg) were detected pre-operation,1,7 and 14 days post-operation,respectively. Blood routine parameters were detected pre-operation 11,3 and 7 days post-operation. Renal function parameters such as blood urea nitrogen (BUN),creatinine (CREA),urea acid (UA) and urea/ creatinine (BU/CREA) were evaluated pre-operation and 30,90,150 days post-operation,respectively. PAAA were removed en bloc to determinine its biofuction and biocompatibility after 5 months of surgery. Kidneys were fixed in neutral buffered formalin solution,pathological slice were conducted to observate pathological changes of kidneys by HE stain.The results are as follows:1. Animal model: The PAAA was implanted to the infrarenal abdominal aortic artery without extensive bleeding after anastomosis. One dog died 2,25 and 127 days post-operation in group 31 mm,respectively,and the overall success rate was 62. 5%. One dog died 7 days post-operation in group 29 mm,the overall success rate was 87. 5%.2. Biofunction and biocompatibility of PAAA: Autopsy showed that there were no abdominal adhesions around the PAAAs,the lumen was patent without blood clots,there were no bleeding in PAAAs in two groups. Biocompatibility was poor because the outer layer of PAAA was enclosed by tissues,which was easy to strip,in group 31 mm. Excellent biocompatibility was proved by vascular endothelial cells growth in the inner layer of PAAA in group 29 mm.3. Coagulation examination: ATPP reduced significantly 1 day post-operation,and returned to normal after 7 days;there was no significant difference on TT in two groups. Fbg increased significantly 1 day post-operation (3. 16 ± 0. 56g/L,P<0. 05),and returned to normal after 7 days; PT and INR have no significant difference in group 29 mm. Value of PT and INR was 7. 92 ± 0. 57s and 0. 655 ± 0. 49,respectively,which reduced significantly compared with base value (P<0. 05),and returned to normal after 7 days; Fbg increased extremely 1 day post-operation (3. 28 ± 0. 49 g /L) (P<0. 01),which still increased significantly after 7 and 14 days in group 31 mm.4. Blood routine examination: Red blood cell count (RBC) and hemoglobin (HGB) reduced significantly 1 and 3days post-operation (P<0. 05); white blood cell count (WBC) and intermediate cell rate (MID%) increased extremely 1 day post-operation; there was no significant change in platelet count in group 29 mm. Mean corpuscular volume (MCV),RBC,HGB reduced significantly 1 and 3 days post-operation; WBC and MID% increased extremely 1 day after surgery; platelet (PLT),thrombocytocrit (PCT%) and platelet distribution width (PDW%) increased significantly1 day post-operation in group 31 mm.5. Renal function: BUN was 3. 995 ± 0. 36 mmol/L,which reduced extremely (P<0. 01),CREA was 104. 5 ±13. 85 μmol/L,which increased significantly (P<0. 05) after 150 days. BU/CREA reduced 90 and 150 days post-operation; UA reduced significantly or extremely 30,90 and 150 days post-operation (P<0. 05,P<0. 01),Its' values were 309. 61 ± 40. 8 μmol/L,160. 26 ± 28. 73 μmol/L and 23. 69 ± 12. 66 μmol/L,respectively in group 29 mm.In group 31 mm,BUN were 5. 51 ± 0. 43 mmol/L and 5. 36 ± 0. 32 mmol/L,which reduced significantly (P <0. 05); BU/CREA reduced significantly (P<0. 05),CREA were 106. 83 ± 7. 0 μmol/L、113. 17 ± 9. 79 μmol/L (P< 0. 05),which increased significantly compared with base values (P<0. 05) 90 and 150 days post-operation. UA reduced significantly or extremely 30,90 and 150 days post-operation (P<0. 05,P<0. 01),its' values were 303. 17 ±39. 2 μmol/L,144. 17. 26 ± 31. 06 μmol/L and 20. 83 ± 11. 52 μmol/L,respectively.6. Pathologic observation of kidney: Glomerular atrophy and granular degeneration in renal tubule with luminal narrowing was observed under microscope. Red thrombosis could be seen in part of renal tubule and renal glomerulus.Animal model of PAAA in dogs was successfully established. Biofunction and biocompatibility of PAAA in group 29mm is better than that of group 31mm. There were great changes in renal function,and obvious pathological changes appeared on kidney post-operation.展开更多
基金supported by Shaanxi Provincial Natural Science Foundation(2023-CX-PT-17 to Sihai Zhao)Natural Science Foundation of Xi'an Jiaotong University Foundation(YXJLRH2022073 to Sihai Zhao)Project of Key Laboratory of Medical Large Animal Models of Guangdong Province(Klmlam 202204 to Sihai Zhao)。
文摘Intimal hyperplasia(IH)is a negative vascular remodeling after arterial injury.IH occasionally occurs in elastase-induced abdominal aortic aneurysm(AAA)mouse models.This study aims to clarify the incidence and histological characteristics of IH in aneurysmal mice.A retrospective study was conducted by including 42 male elastaseinduced mouse AAA models.The IH incidence,aortic diameters with or without IH,and hyperplasia lesional features of mice were analyzed.Among 42 elastase-induced AAA mouse models,10 mice developed mild IH(24%)and severe IH was found in only 2 mice(5%).The outer diameters of the AAA segments in mice with and without IH did not show significant difference.Both mild and severe IH lesions show strong smooth muscle cell positive staining,but endothelial cells were occasionally observed in severe IH lesions.There was obvious macrophage infiltration in the IH lesions of the AAA mouse models,especially in mice with severe IH.However,only a lower numbers of T cells and B cells were found in the IH lesion.Local cell-secreted matrix metalloproteinases(MMP)2 was highly expressed in all IH lesions,but MMP9 was only overexpressed in severe lesions.In conclusion,this study is the first to demonstrate the occurrence of aneurysmal IH and its histological characteristics in an elastaseinduced mouse AAA model.This will help researchers better understand this model,and optimize it for use in AAA-related research.
基金This study was supported by a grant from National Natural Science Foundation of China （No. 30901463）.
文摘Background The pathological characteristics of abdominal aortic aneurysm （AAA） involved the regression of extracellular matrix （ECM） in aortic walls, especially elastic structure in medial layer. As the major structural protein of aorta, elastin contributes to the extensibility and elastic recoil of the vessels. We hypothesized that overexpression of elastin in vessel walls might regenerate the elastic structure of ECM, restore the elastic structure of the aneurysmal wall, and eventually lead to a reduction of aortic diameters （ADs） in an experimental model of AAA. Methods Tropoelastin （TE） of Sprague Dawley （SD） rat was synthesized by reverse transcription polymerase chain reaction and used to construct adneviral vectors containing elastin precursor protein （AdTE-GFP）. Cultured vascular smooth muscle cells （VSMCs） from aortas of male SD rats were transfected with AdTE-GFP, AdGFP, adenoviral vector （AdNull）, and phosphate buffered saline （PBS）. Immunofluorescence staining was performed to determine the expression of elastin in transfected cells. The expression of elastic fibers in ECM of VSMCs transfected with AdTE-GFP were detected by fluorescence microscopy and transmission electron microscopy （TEM） at 1, 3, and 5 days following gene transfer. The AAA vessel walls were infused with AdTE-GFP or an empty AdNull, or PBS directly into the aneurysmal lumen. ADs of the aneurysms were compared in infused aortas. Formation of new elastic fibers in vivo was assessed by hematoxylin and eosin, and elastic von-Giesson staining. Recombinant elastin-GFP in vivo was identified by immunohistochemical staining. Results Elastic fibers were increased both in ECM of VSMC and in vessel walls after gene transfer. Histological studies revealed that the AdTE-GFP-transduced aortas had elastic fiber regeneration in the aneurysmal walls. The AdTE-GFP-transduced aortas showed a decreased AD （23.04%±14.49%, P 〈0.01） in AAA vessel walls. Conclusions Elastic fibers have been successfully overexpressed both in vitro and in a rat model of AAA by a technique of gene transfer. The overexpression of elastic fibers within the aneurysmal tissue appeared to reverse the aneurysm dilatation in this model.
文摘To provide experimental model for abdominal aortic aneurysm research and to optimize design of stent-graft,the authors established an animal models of prosthetic abdominal aortic aneurysm (PAAA) in dogs,evaluated its biofunction,biocompatibility and renal effect.The PAAA was sutured using aneurysm neck (Φ 6 mm artificial blood vessel) and aneurysm body (Φ 29 and 31mm artificial blood vessel,respectively). Sixteen healthy adult dogs,with weight of 13. 5 ± 0. 66 kg,were randomly divided into 2 groups: group 29 mm and group 31 mm,8 in each group. Infrarenal aortic artery was reconstructed with PAAA to establish abdominal aortic aneurysm (AAA) animal model. Blood coagulation index such as prothrombin time (PT),activated partial thromboplatin time (APTT),thrombin time (TT) and Fibrinogen (Fbg) were detected pre-operation,1,7 and 14 days post-operation,respectively. Blood routine parameters were detected pre-operation 11,3 and 7 days post-operation. Renal function parameters such as blood urea nitrogen (BUN),creatinine (CREA),urea acid (UA) and urea/ creatinine (BU/CREA) were evaluated pre-operation and 30,90,150 days post-operation,respectively. PAAA were removed en bloc to determinine its biofuction and biocompatibility after 5 months of surgery. Kidneys were fixed in neutral buffered formalin solution,pathological slice were conducted to observate pathological changes of kidneys by HE stain.The results are as follows:1. Animal model: The PAAA was implanted to the infrarenal abdominal aortic artery without extensive bleeding after anastomosis. One dog died 2,25 and 127 days post-operation in group 31 mm,respectively,and the overall success rate was 62. 5%. One dog died 7 days post-operation in group 29 mm,the overall success rate was 87. 5%.2. Biofunction and biocompatibility of PAAA: Autopsy showed that there were no abdominal adhesions around the PAAAs,the lumen was patent without blood clots,there were no bleeding in PAAAs in two groups. Biocompatibility was poor because the outer layer of PAAA was enclosed by tissues,which was easy to strip,in group 31 mm. Excellent biocompatibility was proved by vascular endothelial cells growth in the inner layer of PAAA in group 29 mm.3. Coagulation examination: ATPP reduced significantly 1 day post-operation,and returned to normal after 7 days;there was no significant difference on TT in two groups. Fbg increased significantly 1 day post-operation (3. 16 ± 0. 56g/L,P<0. 05),and returned to normal after 7 days; PT and INR have no significant difference in group 29 mm. Value of PT and INR was 7. 92 ± 0. 57s and 0. 655 ± 0. 49,respectively,which reduced significantly compared with base value (P<0. 05),and returned to normal after 7 days; Fbg increased extremely 1 day post-operation (3. 28 ± 0. 49 g /L) (P<0. 01),which still increased significantly after 7 and 14 days in group 31 mm.4. Blood routine examination: Red blood cell count (RBC) and hemoglobin (HGB) reduced significantly 1 and 3days post-operation (P<0. 05); white blood cell count (WBC) and intermediate cell rate (MID%) increased extremely 1 day post-operation; there was no significant change in platelet count in group 29 mm. Mean corpuscular volume (MCV),RBC,HGB reduced significantly 1 and 3 days post-operation; WBC and MID% increased extremely 1 day after surgery; platelet (PLT),thrombocytocrit (PCT%) and platelet distribution width (PDW%) increased significantly1 day post-operation in group 31 mm.5. Renal function: BUN was 3. 995 ± 0. 36 mmol/L,which reduced extremely (P<0. 01),CREA was 104. 5 ±13. 85 μmol/L,which increased significantly (P<0. 05) after 150 days. BU/CREA reduced 90 and 150 days post-operation; UA reduced significantly or extremely 30,90 and 150 days post-operation (P<0. 05,P<0. 01),Its' values were 309. 61 ± 40. 8 μmol/L,160. 26 ± 28. 73 μmol/L and 23. 69 ± 12. 66 μmol/L,respectively in group 29 mm.In group 31 mm,BUN were 5. 51 ± 0. 43 mmol/L and 5. 36 ± 0. 32 mmol/L,which reduced significantly (P <0. 05); BU/CREA reduced significantly (P<0. 05),CREA were 106. 83 ± 7. 0 μmol/L、113. 17 ± 9. 79 μmol/L (P< 0. 05),which increased significantly compared with base values (P<0. 05) 90 and 150 days post-operation. UA reduced significantly or extremely 30,90 and 150 days post-operation (P<0. 05,P<0. 01),its' values were 303. 17 ±39. 2 μmol/L,144. 17. 26 ± 31. 06 μmol/L and 20. 83 ± 11. 52 μmol/L,respectively.6. Pathologic observation of kidney: Glomerular atrophy and granular degeneration in renal tubule with luminal narrowing was observed under microscope. Red thrombosis could be seen in part of renal tubule and renal glomerulus.Animal model of PAAA in dogs was successfully established. Biofunction and biocompatibility of PAAA in group 29mm is better than that of group 31mm. There were great changes in renal function,and obvious pathological changes appeared on kidney post-operation.
