RESUMEN
Proteolysis depends on the balance between the proteases and their inhibitors. Matrix metalloproteinase-9 (MMP-9) and its specific inhibitors, tissue inhibitors of metalloproteinases (TIMP), contribute to eosinophilic inflammatory reaction in the subarachnoid space of the Angiostrongylus cantonensis-infected mice. The expression of MMP-9 in cerebrospinal fluid (CSF) was significantly increased in mice with eosinophilic meningitis, compared to that in uninfected ones. However, the TIMP-1 levels were unchanged and remained at basal levels at all time points, even in uninfected mice. Elevated MMP-9 mRNA expression coincided with protein levels and proteolytic activity, as demonstrated by means of positive immunoreactivity and gelatin zymography. CSF protein contents correlated significantly with MMP-9 intensity and CSF eosinophilia. In addition, immunohistochemistry demonstrated MMP-9 and TIMP-1 localization in eosinophils and macrophages. When the specific MMP inhibitor, GM6001, was added, MMP-9 enzyme activity was reduced by 45.4%. The percentage of eosinophil increased significantly upon the establishment of infection, but subsided upon inhibition. These results show that MMP-9/TIMP-1 imbalance in angiostrongyliasis may be associated with eosinophilic meningitis.
Asunto(s)
Angiostrongylus cantonensis , Helmintiasis del Sistema Nervioso Central/líquido cefalorraquídeo , Metaloproteinasa 9 de la Matriz/líquido cefalorraquídeo , Meningitis/líquido cefalorraquídeo , Infecciones por Strongylida/líquido cefalorraquídeo , Animales , Western Blotting , Helmintiasis del Sistema Nervioso Central/patología , Eosinofilia/líquido cefalorraquídeo , Eosinofilia/parasitología , Eosinofilia/patología , Masculino , Metaloproteinasa 9 de la Matriz/genética , Meningitis/parasitología , Meningitis/patología , Ratones , Ratones Endogámicos BALB C , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Infecciones por Strongylida/patología , Espacio Subaracnoideo/patología , Inhibidor Tisular de Metaloproteinasa-1/líquido cefalorraquídeo , Inhibidor Tisular de Metaloproteinasa-1/genética , Regulación hacia ArribaRESUMEN
A hallmark of parasitic meningitis is the infiltration of eosinophils into the subarachnoid space. Infection with Angiostrongylus cantonensis in mice induced proteinase activity in parallel with the pathological changes of eosinophilic meningitis. Zymogram analysis demonstrated that 70 and 55 kDa proteinases from cerebrospinal fluid (CSF) were active against the casein/plasminogen substrate. The proteinase activities were clearly inhibited by phenylmethanesulphonyl fluoride but not by ethylenediamine tetraacetic acid, 1,10-phenanthroline or leupeptin. Western blotting confirmed these enzymes to be tissue-type plasminogen activator and urokinase-type plasminogen activator, respectively. High activities of tissue-type plasminogen activator and urokinase-type plasminogen activator were detected in the CSF of mice with eosinophilic meningitis, and correlated positively with CSF eosinophil numbers and total protein, respectively. Immunohistochemistry demonstrated that tissue-type plasminogen activator and urokinase-type plasminogen activator localised in the endothelial cells of blood vessels, in blood clots and in infiltrated leukocytes. These results suggest that tissue-type plasminogen activator and urokinase-type plasminogen activator may be play a role in the pathogenesis of eosinophilic meningitis of angiostrongyliasis.
Asunto(s)
Angiostrongylus cantonensis , Helmintiasis del Sistema Nervioso Central/líquido cefalorraquídeo , Meningitis/líquido cefalorraquídeo , Meningitis/patología , Activadores Plasminogénicos/líquido cefalorraquídeo , Infecciones por Strongylida/líquido cefalorraquídeo , Animales , Barrera Hematoencefálica , Western Blotting/métodos , Helmintiasis del Sistema Nervioso Central/parasitología , Eosinofilia , Inmunohistoquímica/métodos , Larva , Masculino , Ratones , Ratones Endogámicos BALB C , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Inhibidor 1 de Activador Plasminogénico/líquido cefalorraquídeo , Inhibidor 1 de Activador Plasminogénico/genética , Activadores Plasminogénicos/genética , Distribución Aleatoria , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Infecciones por Strongylida/patología , Activador de Tejido Plasminógeno/líquido cefalorraquídeo , Activador de Tejido Plasminógeno/genética , Activador de Plasminógeno de Tipo Uroquinasa/líquido cefalorraquídeo , Activador de Plasminógeno de Tipo Uroquinasa/genéticaRESUMEN
Angiostrongylosis is a neurological disorder caused by invasion of the central nervous system by developing larvae of Angiostrongylus cantonensis. Purkinje cells in infected mouse cerebellums are small and irregular with degenerative atrophy or partial loss. Ultrastructural changes in degenerative cells included enlarged vacuolar structures and swollen mitochondria within the cytoplasm. The matrix metalloproteinase-9 mRNA which is low in normal cerebellums was expressed in A. cantonensis-infected mice cerebellum prior to Purkinje cell degeneration. Matrix metalloproteinase-9 protein level and enzyme activity increased when the Purkinje cells appeared degenerated. Using immunohistochemistry, matrix metalloproteinase-9 was localised within degenerative Purkinje cells. In addition, when the specific matrix metalloproteinase inhibitor, GM6001, was added, matrix metalloproteinase-9 enzyme activity was reduced by 41.6%. The numbers of degenerative Purkinje cells increased significantly upon establishment of infection but subsided upon inhibition. These results suggested that the expression of matrix metalloproteinase-9 may be associated with degeneration of Purkinje cells in mouse cerebellum infected by A. cantonensis.
