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Background: Amyloid plaques and neurofibrillary tangles are two pathological hallmarks of Alzheimer’s disease (AD). However, synaptic deficits occur much earlier and correlate stronger with cognitive decline than amyloid plaques and neurofibrillary tangles. Mislocalization of tau is an early hallmark of neurodegeneration and precedes aggregations. Sirtuin type 1 (SIRT1) is a deacetylase which acts on proteins including transcriptional factors and associates closely with AD. Objective: The present study investigated the association between SIRT1 and tau expression/tau localization in cells and in mice brains. Methods: Western blot was performed to detected tau, SIRT1, C/EBPα, and GAPDH protein levels. Immunological fluorescence assay was used to assess tau localization in primary cortical neuronal cells. Golgi staining was performed to evaluated dendritic spine morphology in mice brains. Results: In the present study, we found that SIRT1 negatively regulates expression of tau at the transcriptional level through transcriptional factor C/EBPα. Inhibition of the activity of SIRT1 limits the distribution of tau to the neurites. In the meantime, the alteration of dendritic spine morphology is also observed in the brains of SIRT1+/– mice. Conclusion: SIRT1 may be a potential drug target for early intervention in AD.

Hyperphosphorylation of the microtubule associated protein tau is associated with several neurodegenerative diseases including Alzheimer's Disease (AD), collectively referred to as tauopathies. However, the mechanisms by which tau is linked to synaptic dysfunction and memory impairment remain unclear. To address this question, we constructed a mouse model with brain-specific deficiency of SIRT1 (SIRT1 flox/Cre + ). Here, we show that increase of site-specific phosphorylation of tau is coupled with the strengthened O-GlcNAcylation of tau triggered by reduced O-GlcNAcase (OGA) and increased O-GlcNAc transferase (OGT) protein level in the brain of SIRT1 flox/Cre+ mice. SIRT1 deletion in mice brain changes the synaptosomal distribution of site-specific phospho-tau. Learning and memory deficiency induced by dendritic spine deficits and synaptic dysfunction are revealed via SIRT1 flox/Cre+ mice. Our results provide evidence for SIRT1 as a potential therapeutic target in clinical tauopathies.

Tau is modified with O-GlcNAcylation extensively in human brain. The O-GlcNAcylation levels of tau are decreased in Alzheimer's disease (AD) brain. Sirtuin type 1 (SIRT1) is an enzyme that deacetylates proteins including transcriptional factors and associates with neurodegenerative diseases, such as AD. Aberrant SIRT1 expression levels in AD brain is in parallel with the accumulation of tau. cAMP response element binding protein (CREB), a cellular transcription factor, plays a critical role in learning and memory. In this present study, we found SIRT1 deacetylates CREB and inhibits phosphorylation of CREB at Ser133. The inactivated CREB suppresses OGT expression and therefore decreases the O-GlcNAcylation of tau and thus increases the phosphorylation of tau at specific sites. These findings suggest that SIRT1 may be a potential therapeutic target for treating tauopathies.

Private science and technology enterprises are the main force in building a high-level innovative province in Zhejiang, and are also the driving force for the province’s high-quality integration into the Yangtze River Delta. At present, the integration of private science and technology enterprises in Zhejiang into the Yangtze River Delta has problems such as low integration ratio, high integration difficulty, low integration level, and insufficient integration confidence. The causes of the problem mainly include the concept bottlenecks and capacity limitations of private technology companies, the institutional dilemma of cooperation between regional governments and regional business environment synergy is not high, the role of non-governmental organizations is not fully developed. To create a powerful engine that drives private technology enterprises to deeply participate in the development of the Yangtze River Delta, it should be built and strengthened from the perspective of the main role of enterprises themselves, the role of government guidance, industry associations, and other non-governmental organizations to play the role of service coordination and supervision.

The abnormal accumulation of amyloid-b (Ab) and neurofibrillary tangles (NFTs) containing phosphorylated tau proteins are the main histopathological feature of Alzheimer's disease (AD). Synaptic damage and loss are earlier events than amyloid plaques and NFTs in AD progress and best correlate with cognitive deficits in AD patients. Soluble oligomeric Aß initiates the progression of AD and tau mediates the subsequent synaptic impairments at an early stage of AD. In this review we discuss how Ab or/and tau causes synaptic dysfunction. Ab oligomers gather at synapses and give rise to synaptic death in a variety of ways such as regulating receptors and receptor tyrosine kinases, unbalancing calcium homeostasis, and activating caspases and calcineurin. A large amount of hyperphosphorylated tau exists in the synapse of the AD brain. Aß-triggered synaptic deficits are dependent on tau. Soluble, hyperphosphorylated tau is much more correlated to cognitive decline in AD patients. Tau-targeted therapies have received more attention because the treatments targeting Aß failed in AD. Here, we also review the therapy strategies used to intervene in the very early stages of AD. Soluble hyperphosphorylated tau forms a complex with cell surface receptors, scaffold proteins, or intracellular signaling molecules to damage synaptic function. Therefore, therapeutic strategies targeting synaptic tau at the early stage of AD may ameliorating pathology in AD. This review aims to provide an update on the role of oligomeric Ab and soluble hyperphosphorylated tau in the early pathogenesis of Alzheimer's disease and to develop a new treatment strategy based on this.

Calcineurin B-like (CBL) proteins are reported to play significant roles in plant development and ion-transport regulation. Potassium shortages are a serious problem in banana cultivation. However, to date, the members of the banana CBL gene family, and their function in regulating potassium stress, remain unclear. In this study, 11 CBL genes were identified from the banana genome and grouped into four groups (Group I–IV) based on their phylogenetic relationships. The genomic features of these MaCBL genes were analyzed, focusing on their gene structures, standpat motifs, chromosomal distributions, and evolutionary history. Expression pattern analysis revealed that the MaCBLs were function-specific. Further qRT-PCR analysis indicated that the presence of MaCBL2 was indeed a response to potassium deficiency stress. The MaCBL2 gene was cloned, and sequence alignment indicated that it contained four elongation factor hand (EF-hand) domains, the conserved N-terminal myristoylation domain “MGCXXS/K(T)” and the “FPSF” motif. Subcellular location analysis showed that MaCBL2 was located in the plasma membrane, nucleus and cytoplasm. The overexpression of MaCBL2 could restore the growth of the yeast mutant R5421 on a K+-deficient medium. The overexpression of MaCBL2 could promote the root length of transgenic seedlings on K+-deficient medium. These findings indicate that MaCBL2 was, in our study, the key gene of the CBL family in responding to potassium deficiency in bananas. Our discoveries have established a considerable basis for the further study and application of MaCBL genes.

Background: Acid-fast staining for the detection of Mycobacterium tuberculosis has a high false negative-rate, partly due to it is hard to get a good positive control tissue of acid-fast staining. We aimed to design a simple and convenient method for making positive quality controls for acid-fast staining in paraffin-embedded sections.Methods: Three methods were used to get more tuberculous bacteria, which involving centrifugation, mixing, and culture of tubercle bacilli in pleural fluid, prior to the preparation of paraffin-embedded sections.Results: Culturing tubercle bacilli in pleural fluid proved to be, by far, the best of the three methods, with sufficient bacteria, convenient observation, clear staining, and potential for upscaled production.Conclusions: The application of this method should improve the detection rate of tuberculous bacteria, thus facilitating clinical treatment.

With the availability of data and improvement of computation ability, deep learning methods are promising in many areas. Due to the wide deployment of sensors and smart meters in distribution network, abundant data can be obtained, which provides the potential for the application of deep learning in distribution network. In this paper, concept and typical structures of deep learning networks are discussed. Meanwhile, several applications of deep learning in distribution network are summarized. Finally, challenges and prospects are proposed.

Alternative splicing of amyloid precursor protein (APP) exon 7 generates the isoforms containing a Kunitz protease inhibitor (KPI) domain. APP-KPI levels in the brain are correlated with amyloid beta (Aβ) production. Here, we determined the effect of Tetrahydroxystilbene glucoside (TSG) on the AKT-GSK3β pathway. We found GSK3β increased APP-KPI inclusion level and interacted with the splicing factor ASF. TSG was intragastrically administered to 5-month-old APP/PS1 transgenic mice for 12 months. We found that the activated the AKT-GSK3β signaling pathway suppressed APP-KPI inclusion. Moreover, TSG treatment attenuated amyloid deposition in APP/PS1 mice. This study demonstrates the neuroprotective effect of TSG on APP expression, suggesting that TSG may be beneficial for AD prevention and treatment.

Alternative splicing of tau exon 10 generates tau isoforms with three or four microtubule-binding repeats, 3R-tau and 4R-tau, which is equally expressed in adult human brain. Imbalanced expression in 3R-tau and 4R-tau has been found in several sporadic and inherited tauopathies, suggesting that dysregulation of tau exon 10 is sufficient to cause neurodegenerative diseases. We previously reported that Dyrk1A, which is overexpressed in Down syndrome brains, regulates alternative splicing of exogenous tau exon 10. In the present study, we investigated the regulation of endogenous tau exon 10 splicing by Dyrk1A. We found that inhibition of Dyrk1A enhanced tau exon 10 inclusion, leading to an increase in 4R-tau/3R-tau ratio in differentiated-human neuronal progenitors and in the neonatal rat brains. Accompanied with overexpression of Dyrk1A, 3R-tau was increased and 4R-tau was decreased in the neonatal brains of Ts65Dn mice, a model of Down syndrome. Treatment with Dyrk1A inhibitor, green tea flavonol epigallocatechin-gallate (EGCG), from gestation to adulthood suppressed 3R-tau expression and rescued anxiety and memory deficits in Ts65Dn mouse brains. Thus, Dyrk1A might be an ideal therapeutic target for Alzheimer’s disease, especially for Down syndrome and EGCG which inhibits Dyrk1A may have potential effect on the treatment or prevention of this disease.

This article is dedicated to creating a decision support model that helps Chinese road owners select appropriate ETC tags. The main function of this model is to provide a decision tree to guide road owners to find a suitable path to make decision. In this research, our project team interviewed road owners for requirement analysis and listed suitable ETC application samples with appropriate attributes. Based on these samples, we introduced C4.5 algorithm to generate a decision tree model which provided suitable path for decision. After model creation, the validating work confirmed that decision model is applicable for most ETC application scenarios.

Histone deacetylase 6 (HDAC6) controls several major cellular responses to stress that play a role in neurodegenerative diseases, including aggresome formation, autophagy, and apoptosis. However, the specific role of HDAC6 in prion diseases is not known. In this study, we examined the relationship between HDAC6 and cellular response to the neurotoxic synthetic prion protein fragment PrP106-126. We determined that exposure of cerebral cortical neurons to this fragment alters the expression and localization of HDAC6. Suppression of HDAC6 activity or knockdown of HDAC6 expression exacerbates the neuronal cell death induced by PrP106-126, but that overexpression of HDAC6 alleviates PrP106-126-induced neuronal death. We also found that this protective effect of HDAC6 involves the activation of autophagy and modulation of PI3K-Akt-mammalian target of rapamycin (mTOR) signaling. Overexpression of HDAC6 in neurons-induced autophagy correlated with a reduction in phosphorylated mTOR and phosphorylated p70S6K in response to PrP106-126 stimulation, conversely, HDAC6 deficiency interfered with autophagy and increased phosphorylated mTOR and phosphorylated 70S6K. In addition, HDAC6 also appears to modulate the phosphorylation of Akt; overexpression of HDAC6 increased the phosphorylated Akt, but HDAC6 deficiency resulted in further reduction of phosphorylated Akt. Overall, we demonstrate that HDAC6 protects neurons from toxicity of prion peptide, and that this protection occurs at through the regulation of the PI3k-Akt-mTOR axis.

Hyperphosphorylation of tau is pivotally involved in the pathogenesis of Alzheimer’s disease (AD) and related tauopathies. Glycogen synthase kinase-3β (GSK-3β) and protein phosphate 2A (PP2A) are crucial enzymes to regulate tau phosphorylation. GSK-3β activity is regulated by its inhibitory phosphorylation at Ser9. We previously reported the cross-talk between GSK-3β and PP2A signaling and showed that PP2A could dephosphorylate GSK-3β at Ser9. Here, we investigated the dephosphorylation of GSK-3β in brain extracts in the presence of phosphatase inhibitors and found that a PP2A-like phosphatase activity was required for dephosphorylation of GSK-3β at Ser9. PP2A interacted with GSK-3β and suppressed its Ser9 phosphorylation in vitro and in HEK-293FT cells. Activity of PP2A negatively correlated to the level of phosphorylated GSK-3β in kainic acid-induced excitotoxic mouse brain. Alteration of methylation of the catalytic subunit of PP2A (PP2Ac) at Leu309 did not affect GSK-3β phosphorylation. These findings suggest that Leu309 methylation is not required for PP2A to dephosphorylate GSK-3β at Ser9.

As the number of hepatitis hydropericardium syndrome (HHS) cases has increased in recent years in China, development of a safe and effective vaccine is now urgent. To address this problem a subunit vaccine is a good option, we here systematically investigated the minimum immune dose of a subunit vaccine against HHS based on recombinant fowl adenovirus serotype 4 (FAdV-4) fiber-2 protein and compared the effects between this subunit vaccine and an inactivated oil-emulsion FAdV-4 vaccine in a vaccination trial. The results revealed that the lowest dose of recombinant fiber-2 protein that could provide 100% protection against challenge with virulent FAdV-4 strain HB1501 as well as elicit protective immunity was 2.5 μg/bird. Neither clinical signs nor gross lesions were observed in chickens. In addition, immunization of specific-pathogen-free (SPF) chickens with recombinant fiber-2 protein (≥2.5 μg/bird) could induce quicker and stronger immune responses than the inactivated oil-emulsion FAdV-4 vaccine. These findings provide important information about the development of subunit vaccines for the control of HHS.

Approximately equal amounts of 3R-tau and 4R-tau resulting from alternative splicing of tau exon 10 is necessary to maintain normal brain function. Dysregulation of alternative splicing of tau exon 10 and the imbalance of 3R-tau/4R-tau have been seen in inherited and sporadic tauopathies. Splicing factor SC35 (also name as SRSF2) plays an important role in promoting tau exon 10 inclusion. SC35 is post-translationally modified by phosphorylation and acetylation, but the role of acetylation in SC35-medicated tau exon 10 inclusion is unknown. Sirtuin type 1 (SIRT1) is an enzyme that deacetylates proteins and associates with age-related disease such as Alzheimer's disease. In the present study, we determined the role of SIRT1 in SC35 acetylation and in the alternative splicing of tau exon 10. We found that SIRT1 interacts with and deacetylates SC35, and inhibits SC35-promoted tau exon 10 inclusion. Substituting K52 residue of SC35 by arginine impairs the role of SC35 in tau exon 10 inclusion. These results suggest that SIRT1 may serve as a therapeutic target for tauopathy by regulating SC35-mediated tau exon 10 splicing.

Background Previous studies have shown that human cathelicidin and defensins have effective antimicrobial activity against Mycobacterium spp. Objective To investigate the antimycobacterial effect of mature bovine neutrophil β-defensin (mBNBD) 4 against Mycobacterium spp. infection for the first time. Design mBNBD4 protein was expressed in Pichia pastoris GS115. We used immunofluorescent assay to detect whether the recombinant mBNBD4 had entered the macrophages. The antimycobacterial activity of mBNBD4 was tested through colony-forming unit (cfu) assay. Morphological changes in the cell wall of M. bovis treated with mBNBD4 were observed by scanning electron microscope. Results mBNBD4 was expressed and successfully purified from P. pastoris with intact antimicrobial activity. The recombinant protein was able to enter Raw 264.7 macrophages and exhibited potent in vitro bactericidal activity against M. smegmatis and M. bovis. The cell wall of M. bovis was disrupted after interaction with mBNBD4. Exogenous addition of mBNBD4 to both Raw 264.7 and THP-1 derived macrophages reduced the intracellular survival of M. bovis and M. tuberculosis relative to control cells. Conclusion Our data show that mBNBD4 plays an important role in inhibiting mycobacterial growth and in controlling intracellular survival of mycobacteria. mBNBD4 could therefore an effective antimycobacterial molecule in combination with other measures.

Hyperphosphorylation and dysregulation of exon 10 splicing of Tau are pivotally involved in pathogenesis of Alzheimer disease (AD) and/or other tauopathies. Alternative splicing of Tau exon 10, which encodes the second microtubule-binding repeat, generates Tau isoforms containing three and four microtubule-binding repeats, termed 3R-Taus and 4R-Taus, respectively. Dual specificity tyrosine-phosphorylation-regulated kinase 1A (Dyrk1A) lies at the Down syndrome critical region of chromosome 21. Overexpression of this kinase may contribute to the early Tau pathology in Down syndrome via phosphorylation of Tau and dysregulation of Tau exon 10. Here, we report that Dyrk1A was truncated at the C terminus and was associated with overactivation of calpain I in AD brain. Calpain I proteolyzed Dyrk1A in vitro first at the C terminus and further at the N terminus and enhanced its kinase activity toward Tau via increased Vmax but not Km. C-terminal truncation of Dyrk1A resulted in stronger activity than its full-length protein in promotion of exon 10 exclusion and phosphorylation of Tau. Dyrk1A was truncated in kainic acid-induced excitotoxic mouse brains and coincided with an increase in 3R-Tau expression and phosphorylation of Tau via calpain activation. Moreover, truncation of Dyrk1A was correlated with an increase in the ratio of 3R-Tau/4R-Tau and Tau hyperphosphorylation in AD brain. Collectively, these findings suggest that truncation/activation of Dyrk1A by Ca2+/calpain I might contribute to Tau pathology via promotion of exon 10 exclusion and hyperphosphorylation of Tau in AD brain.

Mycobacterium bovis is the causative agent of tuberculosis in cattle. Infection of macrophages with M. bovis leads to the activation of the "nucleotide binding and oligomerization, leucine-rich repeat and pyrin domains-containing protein 3" (NLRP3) and "absent in melanoma 2" (AIM2) inflammasomes, which in turn triggers release of the proinflammatory cytokine interleukin-1β (IL-1β) that contributes to bacterial clearance and plays a crucial role in the host defense. However, NLRP3 and AIM2 inflammasome activation is influenced by several factors and how IL-1β secretion by M. bovis-infected macrophages is regulated via the inflammasome pathway remains unclear. Here we found that IL-1β secretion and pro-IL-1β protein accumulation were inhibited in THP-1 macrophages upon exposure to the virulent M. bovis Beijing strain in the presence of high K(+) concentrations, cycloheximide (a protein synthesis inhibitor) and PR-619 (a deubiquitinating enzyme inhibitor). Scavenging reactive oxygen species (ROS) induced by N-acetylcysteine reduced IL-1β release independent of the mitochondrial permeability transition. Collectively, our results suggest that IL-1β secretion by M. bovis-infected THP-1 macrophages is reduced by high extracellular K(+) concentration, inhibition of new protein synthesis, deubiquitination, and ROS generation.

Axonal degeneration is a hallmark of many neurodegenerative disorders including transmissible spongiform encephalopathies (TSE). However, the full complement of axonal degeneration triggers is not fully understood. In an in vitro prion model, we observed that treatment of rat spinal neurons with the prion peptide, PrP106-126, activated death receptor 6 (DR6, also known as TNFRSF21), caspase-6, caspase-3, and induced axonal degeneration. Knockdown of DR6 by siRNA blocked caspase-6 and caspase-3 activation and axonal degeneration. We also found that cleaved caspase-3 is only enriched in cell bodies, but cleaved caspase-6 is expressed in both cell bodies and axons. Axonal degeneration was prevented by preincubation of neurons with a caspase-6 inhibitor or siRNA of caspase-6. Our findings suggest that both DR6 and caspase-6 play important roles in axonal degeneration and caspase-6 acts downstream of DR6. We also observed that nicotinamide nucleotide adenylyltransferase 1 protein (Nmnat1), which had been reported to protect neurons from degeneration, alleviated axonal degeneration without blocking caspase-6 activation, suggesting that Nmnat acts downstream or parallel to caspase-6 activation. Our results indicate that PrP106-126 triggered axonal degeneration of the spinal cord neurons, DR6 is a key regulator of axonal degeneration, and the signaling pathway of DR6/caspase-6 mediates axonal degeneration induced by the prion fragment. Our findings raise the hope of targeting the DR6 as a potential therapeutic strategy in prion-related neurodegenerative diseases.

Glycogen synthase kinase-3β (GSK-3β) and protein phosphatase 2A (PP2A) are the important enzymes controlling tau hyperphosphorylation. The relationship between these two enzymes and its impact on tau hyperphosphorylation are not well understood. In the present study, we determined the cross talk between PI3K-AKT-GSK-3β and PP2A pathways and found that the former regulated the methylation of PP2Ac via GSK-3β. Upregulation of GSK-3β led to an increase in the methylation and activity of PP2Ac through suppression of protein phosphatase methylesterase-1 expression and phosphorylation of leucine carboxyl methyltransferase 1. PP2A also regulated GSK-3β phosphorylation. Downregulation of PP2A enhanced Ser9 phosphorylation of GSK-3β and inhibited its kinase activity. Thus, GSK-3β and PP2A regulate each other and control tau phosphorylation both directly and indirectly through each other. Reduction of tau phosphorylation by inhibition of GSK-3β may be more than offset by inhibition of PP2A through a shift in phosphatase methylesterase-1/leucine carboxyl methyltransferase 1 balance; PP2A regulates phosphorylation of tau at Ser262/356, a required site for tau pathology. These findings suggest targeting PP2A rather than GSK-3β to inhibit tau pathology.

Prion diseases are known as neurodegenerative diseases of the central nervous system with a long incubation period. Alzheimer's disease (AD) and prion diseases share the hallmark of severe neuronal loss, although their pathogenic mechanisms are similarly incomplete. It appears that these two neurodegenerative diseases share a complex deterioration of function involved in the onset of neuronal loss. To investigate presymptomatic biochemical changes indicative of the initial stage of prion diseases and decipher the pathophysiological mechanisms of these two neurodegenerative diseases, we performed a differential proteomic analysis on brain tissues of 263K-infected hamsters during the presymptomatic period and transgenic APPSWE, PSEN1dE9 mice (a mouse model of AD). We identified 7 differentially expressed proteins including the β-soluble N-ethylmaleimide-sensitive factor attachment protein (β-SNAP) by 2-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The β-SNAP expression patterns in the brains of cases and controls were further quantified by Western blotting. β-SNAP showed an early decrease followed by a progressive depletion. The expression of β-SNAP was also significantly downregulated in the mouse model of AD. β-SNAP is brain-specific and known to bind to the SNAP receptors and is therefore involved in the control of neurotransmitter release as well as in constitutive vesicular transport. Our results suggest that presynaptic failure and abnormalities in neurotransmission may be early events in the development of neuronal dysfunction.

Prion diseases are neurodegenerative disorders characterized by the accumulation of a disease-associated prion protein and apoptotic neuronal death. Previous studies indicated that the ubiquitous expression of c-Abl tyrosine kinase transduces a variety of extrinsic and intrinsic cellular signals. In this study, we demonstrated that a synthetic neurotoxic prion fragment (PrP106-126) activated c-Abl tyrosine kinase, which in turn triggered the upregulation of MST1 and BIM, suggesting the activation of the c-Abl-BIM signaling pathway. The peptide fragment was found to result in cell death via mitochondrial dysfunction in neuron cultures. Knockdown of c-Abl using small interfering RNA protected neuronal cells from PrP106-126-induced mitochondrial dysfunction, production of reactive oxygen species, and apoptotic events inducing translocation of Bax to the mitochondria, cytochrome c release into the cytosol, and activation of caspase-9 and caspase-3. Blocking the c-Abl tyrosine kinase also prevented neuronal cells from PrP106-126-induced apoptotic morphological changes. This is the first study reporting that c-Abl tyrosine kinase as a novel upstream activator of MST1 and BIM plays an important role in prion-induced neuron apoptosis via mitochondrial dysfunction. Our findings suggest that c-Abl tyrosine kinase is a potential therapeutic target for prion disease.

Transmissible spongiform encephalopathies (TSEs) and Alzheimer's disease (AD) belong to a growing family of neurodegenerative disorders that is characterized by the generation of toxic protein aggregates in affected brains (PrP(Sc) and Aβ in TSEs and AD, respectively). To better understand how protein aggregates can modulate microglial processes in these diseases, we treated BV-2 microglia with PrP(106-126) or Aβ1-42 peptides individually at three different concentrations (25-100 μM PrP(106-12) and 2.5-10 μM Aβ1-42) or with a mixture of PrP(106-126) and Aβ1-42 peptides at specified concentrations for 6-24 h. BV-2 microglia chemotaxis, proliferation, and monocyte chemoattractant protein-1 and transforming growth factor-β1 (TGF-β1) secretion were measured and compared between treatments. The results demonstrate that PrP(106-126) and Aβ1-42 peptides induce increases in all four parameters from 6 to 12 h. However, the measured indices plateaued beyond 12 h in BV-2 cells treated >50 μM PrP or >5 μM Aβ1-42, with the exception of TGF-β1 secretion, which continued to increase gradually. Overall, the results of this study indicate that these two peptides may mutually inhibit microglial chemotaxis and proliferation simultaneously via changes induced at the protein level.

The inflammatory responses in Alzheimer's disease and prion diseases are dominated by microglia activation. Three different phenotypes of microglial activation, namely classical activation, alternative activation, and acquired deactivation, have been described. In this study, we investigated the effect of amyloidogenic fragments of amyloid β and prion proteins (Aβ1-42 and PrP106-126) on various forms of microglial activation. We first examined the effect of Aβ1-42 and PrP106-126 stimulation on the mRNA expression levels of several markers of microglial activation, as well as the effect of cytochalasin D, a phagocytosis inhibitor, on microglial activation in Aβ1-42- and PrP106-126-stimulated BV2 microglia. results showed that Aβ1-42 and PrP106-126 induced the classical activation of BV2 microglia, decreased the expression level of alternative expression markers, and had no effect on the expression of acquired deactivation markers. Cytochalasin D treatment significantly reduced Aβ1-42- and PrP106-126-induced up-regulation of proinflammatory factors, but did not change the expression profile of the markers of alternative activation or acquired deactivation in BV2 cells which were exposed to Aβ1-42 and PrP106-126. Our results suggested that microglia interact with amyloidogenic peptides in the extracellular milieu-stimulated microglial classical activation and reduce its alternative activation, and that the uptake of amyloidogenic peptides from the extracellular milieu amplifies the classical microglial activation.

Bovine tuberculosis is a disease in cattle caused by infection with Mycobacterium bovis. The disease has posed significant economic losses and remains a public health hazard worldwide. Interactions between M. bovis and bovine macrophages have been extensively characterized in various studies, while similar analyses in neutrophils, which are one of the other types of white blood cells in mammals, were often overlooked. Neutrophils provide defense against all microbes and can present a diverse collection of antimicrobial molecules, which play an important role in the control of tuberculosis progression. Much of the available data about the involvement of neutrophils in the killing M. bovis is controversial. In this study, we assessed the effect of in vitro infection with M. bovis on some parameters of neutrophils functions including phenotypic changes, apoptosis rate and inflammatory cytokines production. Our results demonstrated that phagocytosis of M. bovis activated and enhanced bovine neutrophils functions as well as initialed their defense mechanism, but failed to eliminate the mycobacteria. Moreover, autophagy might get involved in the defense infection process functioning as a protective mechanism, and inducible-autophagy by lipopolysaccharides stimulation and starvation treatment could efficiently reverse the inability of neutrophils for killing M. bovis, suggesting a potential target for anti-mycobacterial drug-therapy.

Prion diseases are a group of human and animal neurodegenerative disorders caused by the deposition of an abnormal isoform prion protein (PrP(Sc)) encoded by a single copy prion protein gene (PRNP). Prion disease has been reported in many herbivores but not in Equus and the species barrier might be playing a role in resistance of these species to the disease. Therefore, analysis of genotype of prion protein (PrP) in these species may help understand the transmission of the disease. Xiji donkey is a rare species of Equus not widely reared in Ningxia, China, for service, food and medicine, but its PRNP has not been studied. Based on the reported PrP sequence in GenBank we designed primers and amplified, cloned and sequenced the PRNP of Xiji donkey. The sequence analysis showed that the Xiji donkey PRNP was consisted of an open reading frame of 768 nucleotides encoding 256 amino acids. Amino acid residues unique to donkey as compared with some Equus animals, mink, cow, sheep, human, dog, sika deer, rabbit and hamster were identified. The results showed that the amino acid sequence of Xiji donkey PrP starts with the consensus sequence MVKSH, with almost identical amino acid sequence to the PrP of other Equus species in this study. Amino acid sequence analysis showed high identity within species and close relation to the PRNP of sika deer, sheep, dog, camel, cow, mink, rabbit and hamster with 83.1-99.7% identity. The results provided the PRNP data for an additional Equus species, which should be useful to the study of the prion disease pathogenesis, resistance and cross species transmission.

Prion diseases are a group of transmissible fatal neurodegenerative disorders of humans and animals, including bovine spongiform encephalopathy, scrapie, and Creutzfeldt-Jakob disease. Microglia, the resident macrophages of the central nervous system, are exquisitely sensitive to pathological tissue alterations, altering their morphology and phenotype to adopt a so-called activated state and perform immunological functions in response to pathophysiological brain insults. Although recent findings have provided valuable insights into the role microglia play in the proinflammatory events observed in prion, the intracellular signaling molecules responsible for the initiation of these responses remain to be elucidated. It seems that microglial activation involve PrP106-126 binding and the activation of cell surface immune and adhesion molecules such as CD36 and integrins, with the subsequent recruitment of Src family tyrosine kinases such as Fyn, Lyn, and Syk kinases. In the present study, we show that CD36 is involved in PrP106-126-induced microglial activation and that PP2 and piceatannol (Pic) can abrogate neurotoxic prion peptides-induced inducible nitric oxide synthase activation in microglia. These findings unveil a previously unrecognized role of PP2 and Pic as Src family kinase Fyn and the tyrosine kinase Syk inhibitor involved in neurotoxic prion peptides-microglia interactions, thus providing new insights into mechanisms underlying the activation of microglia by neurotoxic prion peptides.

Mycobacterium bovis, the classical causative agent of bovine tuberculosis (BTB), infects animals of agricultural importance and other mammals, including humans. Neutrophils are one of the first lines of defense against all microbes and produce a diverse collection of antimicrobial molecules, which play an important role in the early control of tuberculosis progression. An interferon (IFN)-inducible neutrophil-driven blood transcriptional signature that consisted of both IFN-γ and type I IFN-α/β signaling has been identified in human tuberculosis, supporting a role for neutrophils in the pathogenesis of tuberculosis disease. However, it is unknown whether bovine neutrophils play a similar role during M. bovis infection. Thus, we assessed the expression levels of ten IFN-inducible transcriptional genes in neutrophils from healthy cattle stimulated by M. bovis and neutrophils isolated from three groups of cattle of different infection status, and in addition, examined the changes in the expression of myeloperoxidase (MPO) and pentraxin-related protein pentraxin-inducible protein (PTX3) genes during bovine tuberculosis infection. Our results demonstrated a specific expression pattern of IFN-inducible transcriptional genes and MPO and PTX3 genes in neutrophils during bovine tuberculosis infection. The observed expression pattern provides a potential diagnostic tool, which may have implications for vaccine and therapeutic development to combat the bovine tuberculosis epidemic.