Poisoning by Nierembergia veitchii: Effects on vascular smooth muscle cells in the pathogenesis of enzootic calcinosis.
Vet Pathol
; 59(5): 814-823, 2022 09.
Article
em En
| MEDLINE
| ID: mdl-35587717
ABSTRACT
Vascular mineralization is a hallmark of enzootic calcinosis. Histopathological, ultrastructural, and immunohistochemical investigations were performed on the external carotid arteries of seven sheep naturally poisoned by Nierembergia veitchii. Histologically, moderate to marked hyperplasia of the tunica intima was observed without mineralization. The tunica media exhibited mild to severe mineralization and osteochondroid metaplasia. Sheep with enzootic calcinosis showed arterial overexpression of osteopontin and tissue-nonspecific alkaline phosphatase and immunolabeling for osteonectin and osteocalcin in both intima and media layers of the tested arteries. The main ultrastructural finding in the tunica media was a marked phenotypic change of vascular smooth muscle cells from a contractile phenotype (VSMC-C) into a synthetic phenotype (VSMC-S). In the tunica media, VSMC-S produced matrix and extracellular vesicles, forming mineralizable granules associated with arterial mineralization. VSMC-S were also present in the tunica intima, but matrix and extracellular vesicles and mineralization were not observed. The absence of matrix and extracellular vesicles in the intimal hyperplasia, even in the presence of noncollagenous bone proteins, tissue-nonspecific alkaline phosphatase, and vitamin D receptors, reinforces the hypothesis that the presence of matrix and extracellular vesicles are crucial for the development of vascular mineralization in enzootic calcinosis. It is proposed that the two different VSMC-S phenotypes in calcinosis are due to the expression of at least two genetically different types of these cells induced by the action of 1,25(OH)2D3.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Doenças dos Ovinos
/
Calcinose
/
Hiperplasia
Tipo de estudo:
Etiology_studies
Limite:
Animals
Idioma:
En
Revista:
Vet Pathol
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Uruguai