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Veterinary Microbiology Oct 2014Sheep scrapie is a transmissible spongiform encephalopathy (TSE), progressive and fatal neurodegenerative diseases of the central nervous system (CNS) linked to the...
Sheep scrapie is a transmissible spongiform encephalopathy (TSE), progressive and fatal neurodegenerative diseases of the central nervous system (CNS) linked to the accumulation of misfolded prion protein, PrP(Sc). New Zealand Cheviot sheep, homozygous for the VRQ genotype of the PRNP gene are most susceptible with an incubation period of 193 days with SSBP/1 scrapie. However, the earliest time point that PrP(Sc) can be detected in the CNS is 125 days (D125). The aim of this study was to quantify changes to the transcriptome of the thalamus and obex (medulla) at times immediately before (D75) and after (D125) PrP(Sc) was detected. Affymetrix gene arrays were used to quantify gene expression in the thalamus and Illumina DGE-tag profiling for obex. Ingenuity Pathway Analysis was used to help describe the biological processes of scrapie pathology. Neurological disease and Cancer were common Bio Functions in each tissue at D75; inflammation and cell death were major processes at D125. Several neurological receptors were significantly increased at D75 (e.g. CHRNA6, GRM1, HCN2), which might be clues to the molecular basis of psychiatric changes associated with TSEs. No genes were significantly differentially expressed at both D75 and D125 and there was no progression of events from earlier to later time points. This implies that there is no simple linear progression of pathological or molecular events. There seems to be a step-change between D75 and D125, correlating with the detection of PrP(Sc), resulting in the involvement of different pathological processes in later TSE disease.
Topics: Animals; Brain; Disease Progression; Gene Expression Profiling; Genotype; Microarray Analysis; New Zealand; PrPSc Proteins; Scrapie; Sheep, Domestic; Time Factors; Transcriptome
PubMed: 25183238
DOI: 10.1016/j.vetmic.2014.07.026 -
Human Brain Mapping Dec 2018Observations in witnessed Sudden Unexpected Death in Epilepsy (SUDEP) suggest that a fatal breakdown of the central autonomic control could play a major role in SUDEP. A...
Observations in witnessed Sudden Unexpected Death in Epilepsy (SUDEP) suggest that a fatal breakdown of the central autonomic control could play a major role in SUDEP. A previous MR study found volume losses in the mesencephalon in focal epilepsy that were more severe and extended into the lower brainstem in two patients who later died of SUDEP. The aims of this study were to demonstrate an association (1) between brainstem volume loss and impaired autonomic control (reduced heart rate variability [HRV]); (2) between brainstem damage and time to SUDEP in patients who later died of SUDEP. Two populations were studied: (1) Autonomic system function population (ASF, 18 patients with focal epilepsy, 11 controls) with HRV measurements and standardized 3 T MR exams. (2) SUDEP population (26 SUDEP epilepsy patients) with clinical MRI 1-10 years before SUDEP. Deformation-based morphometry of the brainstem was used to generate profile similarity maps from the resulting Jacobian determinant maps that were further characterized by graph analysis to identify regions with excessive expansion indicating significant volume loss or atrophy. The total number of regions with excessive expansion in ASF was negatively correlated with HRV (r = -.37, p = .03), excessive volume loss in periaqueductal gray/medulla oblongata autonomic nuclei explained most of the HRV associated variation (r/r = -.82/.67, p < .001). The total number of regions with excessive expansion in SUDEP was negatively correlated with time to SUDEP (r = -.39, p = .03), excessive volume loss in the raphe/medulla oblongata at the obex level explained most of the variation of the time between MRI to SUDEP (r/r = -.60/.35,p = .001). Epilepsy is associated with brainstem atrophy that impairs autonomic control and can increase the risk for SUDEP if it expands into the mesencephalon.
Topics: Adolescent; Adult; Atrophy; Autonomic Nervous System; Brain Stem; Child; Child, Preschool; Death, Sudden; Epilepsies, Partial; Epilepsy; Female; Heart Rate; Humans; Infant; Magnetic Resonance Imaging; Male; Middle Aged; Young Adult
PubMed: 30096213
DOI: 10.1002/hbm.24325 -
The Journal of Veterinary Medical... Nov 2021There has been no report on Chronic wasting disease (CWD) cases in Japan to date; however, there is concern about the geographic spread of CWD. To clarify the CWD status...
There has been no report on Chronic wasting disease (CWD) cases in Japan to date; however, there is concern about the geographic spread of CWD. To clarify the CWD status in Japan, we conducted CWD monitoring using real-time quaking-induced conversion (RT-QuIC) assay which can detect the low level of CWD prions. A total of 690 obex samples collected from sika deer and Reeves's muntjac in Hokkaido and Honshu was tested for CWD prions. No CWD-positive cases were found, suggesting that CWD is nonexistent in Japan. Our results also indicate that RT-QuIC assay is useful for continuous monitoring of CWD. Furthermore, nucleotide sequence analysis of the PrP gene revealed sika deer in Japan harbor CWD susceptible allele.
Topics: Animals; Biological Assay; Deer; Japan; Prions; Wasting Disease, Chronic
PubMed: 34556606
DOI: 10.1292/jvms.21-0368 -
Veterinary Research Oct 2016Scrapie and bovine spongiform encephalopathy (BSE) are transmissible spongiform encephalopathies (TSE's) affecting sheep and goats. Susceptibility of goats to scrapie is...
Scrapie and bovine spongiform encephalopathy (BSE) are transmissible spongiform encephalopathies (TSE's) affecting sheep and goats. Susceptibility of goats to scrapie is influenced by polymorphisms of the prion protein gene (PRNP) of the host. Five polymorphisms are associated with reduced susceptibility to TSE's. In the study presented here caprine samples from a scrapie eradication program on Cyprus were genotyped and further characterized using BioRad TeSeE rapid test, histological, immunohistochemical and biochemical methods. In total 42 goats from 20 flocks were necropsied from which 25 goats showed a positive result in the rapid test, a spongiform encephalopathy and an accumulation of pathological prion protein (PrP) in the obex. PrP deposits were demonstrated in the placenta, peripheral nervous and lymphoreticular system. Two animals showed PrP-accumulations in peripheral tissues only. By discriminatory immunoblots a scrapie infection could be confirmed for all cases. Nevertheless, slight deviations in the glycosylation pattern might indicate the presence of different scrapie strains. Furthermore scrapie samples from goats in the current study demonstrated less long term resistance to proteinase K than ovine or caprine BSE control samples. Reduced scrapie susceptibility according to the PRNP genotype was demonstrated (Fishers Exact test, p < 0.05) for the goats with at least one polymorphism (p = 0.023) at the six codons examined and in particular for those with polymorphisms at codon 146 (p = 0.016). This work characterizes scrapie in goats having implications for breeding and surveillance strategies.
Topics: Animals; Cyprus; Female; Goat Diseases; Goats; Prion Diseases; Prion Proteins
PubMed: 27716411
DOI: 10.1186/s13567-016-0379-0 -
Veterinary Research Jun 2020In a study originally designed to find potential risk factors for bovine spongiform encephalopathy (BSE) we examined tissues from 403 Holstein Frisian cattle in total....
In a study originally designed to find potential risk factors for bovine spongiform encephalopathy (BSE) we examined tissues from 403 Holstein Frisian cattle in total. These included 20 BSE cattle and their 236 birth- and feeding cohort animals plus 32 offspring, 103 age, breed and district-matched control cattle and further twelve cattle with neurological signs. In addition to the obex, we examined the celiac ganglion, cervical cranial ganglion, trigeminal ganglion and proximal ganglion of the vagus nerve using histological techniques. Unexpectedly, we found a high number of neurofibroma, a benign peripheral nerve sheath tumor consisting of Schwann cells, fibroblasts and perineural cells. The neurofibroma were present only in the celiac ganglion and found during histologic examination. With a frequency of 9.91% in BSE cattle and their cohorts (case animals) and 9.09% in the age, breed and district matched control animals there seems to be no correlation between the occurrence of BSE and neurofibroma. Benign peripheral nerve sheath tumors have been described more often in cattle than in other domestic animals. Usually, they are incidental macroscopic findings in the thoracic ganglia during meat inspection. To our knowledge, there are no previous systematic histologic studies including bovine celiac ganglia at all. The high incidence of celiac ganglia neurofibroma may play a role in the frequently occurring abomasal displacements in Holstein Frisian cattle as the tumors might cause a gastrointestinal motility disorder. At present a genetic predisposition for these neoplasms cannot be ruled out.
Topics: Animals; Cattle; Cattle Diseases; Cohort Studies; Female; Ganglia, Sympathetic; Germany; Incidence; Male; Neurofibroma; Risk Factors
PubMed: 32552868
DOI: 10.1186/s13567-020-00800-1 -
Oncotarget Jul 2017Bovine spongiform encephalopathy, a member of transmissible spongiform encephalopathies, has not been reported in buffaloes, Bubalus bubalis. Prion protein (PrP),...
Bovine spongiform encephalopathy, a member of transmissible spongiform encephalopathies, has not been reported in buffaloes, Bubalus bubalis. Prion protein (PrP), encoded by the prion protein gene (PRNP), is fundamental in the pathogenesis of transmissible spongiform encephalopathies. We previously showed that buffaloes express more PrP proteins but lower PRNP mRNA than cattle in several pivotal tissues like the obex. Therefore, we sought to establish whether genetic variability in PRNP 3'UTR, mediated by miRNA down-regulation, causes PrP expression differences between cattle and buffaloes. We annotated the 3'UTR of buffalo PRNP gene by 3'RACE experiment. A total of 92 fixed differences in the complete 3'UTR (~ 3 kb) were identified between 13 cattle and 13 buffaloes. Resequencing of UTR-C (g.786-1436) and UTR-B (g.778-1456) fragments confirmed that all mutations except g.1022T in cattle are fixed differences between 147 cattle and 146 buffaloes. In addition, analysis of the variation of ΔG between cattle and buffalo sequences reveals four remarkable differences. Two buffalo-specific insertion sites (a 28-bp insertion and an AG insertion in buffalo 3'UTR of PRNP g.970-997 and g. 1088-1089, respectively) and two mutants (g. 1007-1008 TG→CC) create compatible binding sites for miRNAs in buffalo 3'UTR. This was validated through luciferase reporter assays which demonstrated that miR-125b-5p, miR-132-3p, miR-145-5p, miR-331-3p, and miR-338-3p directly act on the fixed difference sites in buffalo 3'UTR. Additional expressional analyses show that these five miRNAs are coexpressed with PRNP in bovine obex tissues. Our study reveals a miRNAs regulated mechanism explaining the differences in prion expression between cattle and buffalo.
Topics: 3' Untranslated Regions; Alleles; Animals; Binding Sites; Buffaloes; Cattle; Computational Biology; Encephalopathy, Bovine Spongiform; Genotype; INDEL Mutation; MicroRNAs; Prion Proteins; RNA Processing, Post-Transcriptional; Sequence Analysis, DNA
PubMed: 28545018
DOI: 10.18632/oncotarget.17545 -
ENeuro 2020Vagal afferent sensory nerves, originating in jugular and nodose ganglia, are composed of functionally distinct subsets whose activation evokes distinct thoracic and...
Vagal afferent sensory nerves, originating in jugular and nodose ganglia, are composed of functionally distinct subsets whose activation evokes distinct thoracic and abdominal reflex responses. We used Cre-expressing mouse strains to identify specific vagal afferent populations and map their central projections within the brainstem. We show that Pirt is expressed in virtually all vagal afferents; whereas, 5-HT3 is expressed only in nodose neurons, with little expression in jugular neurons. Transient receptor potential vanilloid 1 (TRPV1), the capsaicin receptor, is expressed in a subset of small nodose and jugular neurons. Tac1, the gene for tachykinins, is expressed predominantly in jugular neurons, some of which also express TRPV1. Vagal fibers project centrally to the nucleus tractus solitarius (nTS), paratrigeminal complex, area postrema, and to a limited extent the dorsal motor nucleus of the vagus. nTS subnuclei preferentially receive projections by specific afferent subsets, with TRPV1 fibers terminating in medial and dorsal regions predominantly caudal of obex, whereas TRPV1 fibers terminate in ventral and lateral regions throughout the rostral-caudal aspect of the medulla. Many vagal Tac1 afferents (mostly derived from the jugular ganglion) terminate in the nTS. The paratrigeminal complex was the target of multiple vagal afferent subsets. Importantly, lung-specific TRPV1 and Tac1 afferent terminations were restricted to the caudal medial nTS, with no innervation of other medulla regions. In summary, this study identifies the specific medulla regions innervated by vagal afferent subsets. The distinct terminations provide a neuroanatomic substrate for the diverse range of reflexes initiated by vagal afferent activation.
Topics: Afferent Pathways; Animals; Brain Stem; Carrier Proteins; Membrane Proteins; Mice; Nodose Ganglion; Solitary Nucleus; TRPV Cation Channels; Vagus Nerve
PubMed: 32060036
DOI: 10.1523/ENEURO.0494-19.2020 -
The Journal of Veterinary Medical... May 2019A captured Japanese wild boar (Sus scrofa leucomystax) fetus was dicephalic. The fetus had two heads, but one body from the cranial neck region. Computed tomography...
A captured Japanese wild boar (Sus scrofa leucomystax) fetus was dicephalic. The fetus had two heads, but one body from the cranial neck region. Computed tomography imaging revealed that the two crania merged at the occipital bone, and the vertebral bodies between the atlas and the seventh thoracic vertebra were deformed. The fetus was found to have two tongues and laryngopharynges, but its esophagus and trachea were not duplicated. Each head contained a cerebrum and cerebellum, but the brains merged at the obex of the medulla oblongata, and the cervical spinal cord had duplicated ventral clefts. The heart was composed of three atria and four ventricles. This is the first report of a dicephalus with cardiac malformation in a wild boar.
Topics: Animals; Fetus; Heart Defects, Congenital; Japan; Sus scrofa; Tomography, X-Ray Computed; Twins, Conjoined
PubMed: 30853669
DOI: 10.1292/jvms.18-0765 -
Molecular Pain 2018Background The mechanisms underlying tooth pulp hypersensitivity associated with masseter muscle hyperalgesia remain largely underinvestigated. In the present study, we...
Background The mechanisms underlying tooth pulp hypersensitivity associated with masseter muscle hyperalgesia remain largely underinvestigated. In the present study, we aimed to determine whether masseter muscle contraction induced by daily electrical stimulation influences the mechanical head-withdrawal threshold and genioglossus electromyography activity caused by the application of capsaicin to the upper first molar tooth pulp. We further investigated whether astroglial glutamine synthesis is involved in first molar tooth pulp hypersensitivity associated with masseter muscle contraction. Methods The first molar tooth pulp was treated with capsaicin or vehicle in masseter muscle contraction or sham rats, following which the astroglial glutamine synthetase inhibitor methionine sulfoximine or Phosphate buffered saline (PBS) was applied. Astroglial activation was assessed via immunohistochemistry. Results The mechanical head-withdrawal threshold of the ipsilateral masseter muscle was significantly decreased in masseter muscle contraction rats than in sham rats. Genioglossus electromyography activity was significantly higher in masseter muscle contraction rats than sham rats. Glial fibrillary acidic protein-immunoreactive cell density was significantly higher in masseter muscle contraction rats than in sham rats. Administration of methionine sulfoximine induced no significant changes in the density of glial fibrillary acidic protein-immunoreactive cells relative to PBS treatment. However, mechanical head-withdrawal threshold was significantly higher in masseter muscle contraction rats than PBS-treated rats after methionine sulfoximine administration. Genioglossus electromyography activity following first molar tooth pulp capsaicin treatment was significantly lower in methionine sulfoximine-treated rats than in PBS-treated rats. In the ipsilateral region, the total number of phosphorylated extracellular signal-regulated protein kinase immunoreactive cells in the medullary dorsal horn was significantly smaller upon first molar tooth pulp capsaicin application in methionine sulfoximine-treated rats than in PBS-treated rats. Conclusions Our results suggest that masseter muscle contraction induces astroglial activation, and that this activation spreads from caudal to the obex in the medullary dorsal horn, resulting in enhanced neuronal excitability associated with astroglial glutamine synthesis in medullary dorsal horn neurons receiving inputs from the tooth pulp. These findings provide significant insight into the mechanisms underlying tooth pulp hypersensitivity associated with masseter muscle contraction.
Topics: Animals; Astrocytes; Capsaicin; Dental Pulp; Electric Stimulation; Electromyography; Extracellular Signal-Regulated MAP Kinases; Glial Fibrillary Acidic Protein; Glutamine; Hyperalgesia; Male; Masseter Muscle; Medulla Oblongata; Methionine Sulfoximine; Molar; Muscle Contraction; Phosphorylation; Posterior Horn Cells; Rats, Sprague-Dawley
PubMed: 29448913
DOI: 10.1177/1744806918763270 -
PloS One 2016Protein tyrosine kinase (PTK) mediated the tyrosine phosphorylation modification of neuronal receptors and ion channels. Whether such modification resulted in changes of...
Protein tyrosine kinase (PTK) mediated the tyrosine phosphorylation modification of neuronal receptors and ion channels. Whether such modification resulted in changes of physiological functions was not sufficiently studied. In this study we examined whether the hypoxic respiratory response-which is the enhancement of breathing in hypoxic environment could be affected by the inhibition of PTK at brainstem ventral respiratory neuron column (VRC). Experiments were performed on urethane anesthetized adult rabbits. Phrenic nerve discharge was recorded as the central respiratory motor output. Hypoxic respiratory response was produced by ventilating the rabbit with 10% O2-balance 90% N2 for 5 minutes. The responses of phrenic nerve discharge to hypoxia were observed before and after microinjecting PTK inhibitor genistein, AMPA receptor antagonist CNQX, or inactive PTK inhibitor analogue daidzein at the region of ambiguus nucleus (NA) at levels 0-2 mm rostral to obex where the inspiratory subgroup of VRC were recorded. Results were as follows: 1. the hypoxic respiratory response was significantly attenuated after microinjection of genistein and/or CNQX, and no additive effect (i.e., further attenuation of hypoxic respiratory response) was observed when genistein and CNQX were microinjected one after another at the same injection site. Microinjection of daidzein had no effect on hypoxic respiratory response. 2. Fluorescent immunostaining showed that hypoxia significantly increased the number of phosphotyrosine immunopositive neurons in areas surrounding NA and most of these neurons were also immunopositive to glutamate AMPA receptor subunit GluR1. These results suggested that PTK played an important role in regulating the hypoxic respiratory response, possibly through the tyrosine phosphorylation modification of glutamate AMPA receptors on the respiratory neurons of ventral respiratory neuron column.
Topics: 6-Cyano-7-nitroquinoxaline-2,3-dione; Animals; Brain Stem; Female; Hypoxia; Male; Microinjections; Neurons; Phosphotyrosine; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Rabbits; Receptors, AMPA; Respiration
PubMed: 27798679
DOI: 10.1371/journal.pone.0165895