eNOS and iNOS trigger apoptosis in the brains of sheep and goats naturally infected with the border disease virus.

In this study, apoptotic and anti-apoptotic mechanisms and if present, which pathway to trigger the apoptosis in the brains of Border Disease Virus (BDV) infected lambs (n=10) and goat kids (n=5) were investigated. Briefly, apoptotic (caspase 3, caspase 9) and anti-apoptotic markers (Bcl-2), cytokine response (TNF-α, INF-γ), reactive gliosis and myelin loss were examined. eNOS, iNOS, caspase 9, caspase 3 and GFAP expressions were higher in BDV infected tissues compared to control animals (6 kids and 6 lambs) (p<0.05). Double immunoperoxidase test revealed that TUNEL positive apoptotic cells showed significant association with increased eNOS-iNOS and iNOS-BDV expressions. However, no significant differences were found for TNFR1, TNF-α and INF-γ expressions in BD (p>0.05). There was a positive correlation between the intensity of myelin loss, GFAP activity and severity of infection. Inconclusion, as a novel finding, it is established that eNOS and iNOS overexpressions are co-associated with apoptosis in BDV infected neurons and neuroglia. The results also strongly suggested that BDV infected apoptotic cells mainly prefer the intrinsic pathway that might be most likely related to increased nitric oxide levels.

Increased expressions of ADAMTS-13, neuronal nitric oxide synthase, and neurofilament correlate with severity of neuropathology in Border disease virus-infected small ruminants.

Border Disease (BD), caused by Pestivirus from the family Flaviviridae, leads to serious reproductive losses and brain anomalies such as hydranencephaly and cerebellar hypoplasia in aborted fetuses and neonatal lambs. In this report it is aimed to investigate the expression of neuronal nitric oxide synthase (nNOS), A Disintegrin And Metalloprotease with Thrombospondin type I repeats-13 (ADAMTS-13), and neurofilament (NF) in the brain tissue in small ruminants infected with Border Disease Virus (BDV) and to identify any correlation between hypomyelinogenesis and BD neuropathology. Results of the study revealed that the levels of ADAMTS-13 (p<0.05), nNOS (p<0.05), and NF (p<0.05) were remarkably higher in BDV-infected brain tissue than in the uninfected control. It was suggested that L-arginine-NO synthase pathway is activated after infection by BDV and that the expression of NF and nNOS is associated with the severity of BD. A few studies have focused on ADAMTS-13 expression in the central nervous system, and its function continues to remain unclear. The most prominent finding from our study was that ADAMTS-13, which contain two CUB domains, has two CUB domains and its high expression levels are probably associated with the development of the central nervous system (CNS). The results also clearly indicate that the interaction of ADAMTS-13 and NO may play an important role in the regulation and protection of the CNS microenvironment in neurodegenerative diseases. In addition, NF expression might indicate the progress of the disease. To the best of the authors'knowledge, this is the first report on ADAMTS-13 expression in the CNS of BDV-infected small ruminants.

Effects of congenital infection of sheep with border disease virus on myelin proteins.

Border disease (BD) of sheep is caused by a virus in the genus Pestivirus that results in decreased myelination throughout the CNS when acquired congenitally. Pregnant ewes were inoculated with BD virus at 50 days of gestation, and myelin proteins were quantified in several regions of the CNS during prenatal and postnatal development of infected lambs for comparison with age-matched controls. Newborn field-infected lambs were also examined. Myelin basic protein (MBP), proteolipid protein (PLP), myelin-associated glycoprotein (MAG), and 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) were measured by densitometric scanning of western blots. Deficiencies in the myelin proteins were detected as early as 116 days of gestation, and the deficiencies of myelin proteins were most pronounced in the cerebellum at all ages examined. PLP and MBP increased from 10-30% of normal in cerebellar white matter at birth to 40-60% of normal at 6 months, suggesting some catch-up in the amount of compact myelin with development. MAG and CNP were between 70 and 80% of control levels in the cerebellum at birth and at 6 months. Similar results were obtained for the corpus callosum and spinal cord of infected lambs, but the deficiencies of myelin proteins were not as great. A common finding in all regions examined was that MBP and PLP were reduced more than MAG and CNP. This is probably explained by a greater deficit of compact myelin, in which MBP and PLP are localized, than of associated oligodendroglial membranes, in which MAG and CNP are concentrated.(ABSTRACT TRUNCATED AT 250 WORDS)