Collagen-I, Collagen-IV and Aquaporin-IV Protein Expressions Are Up-Regulated in Sheep Naturally Infected with Coenurosis; A Histopathological and Immunohistochemical Study

Coenurosis is defined as a common zoonotic disease caused by the larval form of Taenia multiceps, C. cerebralis. Research into the components constituting the extracellular matrix (ECM) for coenurosis in domestic animals is limited. The current study aims to investigate the local tissue expression of important ECM components, including Collagen-I (Col-I), Collagen-IV (Col-IV), and Aquaporin-IV (AQP-IV) in healthy and naturally infected sheep with coenurosis. The study material consisted of 6 healthy and 21 coenurosis-positive sheep, totaling 27 brain tissue samples. Brain tissues of the control group animals exhibited normal histology. In sheep infected with Coenurosis, cyst structures and, in some cases, necrotic changes within the cystic areas, as well as the formation of numerous multinucleated giant cells surrounding the cyst wall, mononuclear cell infiltrations, eosinophilic granulocytes, hyperemia, meningitis, perivascular mononuclear cell infiltrations, and neuronal necrosis, neuronophagy, and gliosis in the neuropil tissue adjacent to the cystic structures were observed. Immunohistochemically, compared to the control group, significant increases in the expression of Col-I (p<0.001), Col-IV (p<0.001), and AQP-IV (p<0.01) were detected in sheep infected with coenurosis. These findings suggest that the increased expression of Col-I, Col-IV, and AQP-IV in C. cerebralis infection may play important roles in regulating brain edema, glial response, and fibrotic processes. Our present results highlight the importance of local expression of Col-I, Col-IV and AQP-IV in naturally infected sheep with coenurosis and may contribute to a better understanding of the pathophysiology of the disease and provide new perspectives for possible treatment strategies.