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  • Bojesen posted an update 7 months, 2 weeks ago

    I also describe an overview of the challenges encountered in investigating underlying synaptic mechanisms and highlight recent technical approaches that may overcome these difficulties and provide new insights into synaptic mechanisms for cortical processing involving long-range connectivity.Technological advances in transmission electron microscopes and detectors have turned cryogenic electron microscopy (cryo-EM) into an essential tool for structural biology. A commonly used cryo-EM data analysis method, single particle analysis, averages hundreds of thousands of low-dose images of individual macromolecular complexes to determine a density map of the complex. The presence of symmetry in the complex is beneficial since each projection image can be assigned to multiple views of the complex. However, data processing that applies symmetry can average out asymmetric features and consequently data analysis methods are required to resolve asymmetric structural features. Scipion is a cryo-EM image processing framework that integrates functionalities from different image processing packages as plugins. To extend its functionality for handling symmetry mismatches, we present here a Scipion plugin termed LocalRec implementing the localized reconstruction method. When tested on an adenovirus data set, the plugin enables resolving the symmetry-mismatched trimeric fibre bound to the five-fold vertices of the capsid. Furthermore, it improves the structure determination of the icosahedral capsid by dealing with the defocus gradient across the particle. LocalRec is expected to be widely applicable in a range of cryo-EM investigations of flexible and symmetry mismatched complexes.Ochratoxin A (OTA) is a dietary mycotoxin that can cause nephrotoxicity, hepatotoxicity, neurotoxicity and carcinogenicity. We found that in mice OTA is transported by the drug transporters mouse (m)ABCB1 and/or mABCG2, mOATP1A/1B, and human (h)OATP1B3. CPI-203 cost The complete deletion of mABCB1 and mABCG2 resulted in ~2-fold higher OTA liver and kidney accumulation upon intravenous injection. Upon oral administration, absence of mOATP1A/1B led to a substantial (>3-fold) decrease in hepatic and small intestinal exposure of OTA. Furthermore, in humanized mouse strains, hepatic expression of transgenic hOATP1B3, but not hOATP1B1, partly reversed the reduced liver concentration of OTA in mOATP1A/1B knockout mice. These data indicate that transgenic hOATP1B3 can significantly transport OTA into the liver, and can at least partly compensate for the loss of the mOATP1A/1B transporters. This study shows that some ABC and OATP transporters can substantially affect the pharmacokinetics of OTA, which might have implications for its toxicity behavior.NLRP3, one of the HSP-90 clients, has been defined as a critical component of IBD. In a rat model of DSS-induced colitis, we investigated the anti-inflammatory potential of the combined therapy with CP-456773 (CP), an NLRP3 inhibitor, and celastrol (CSR), an NF-κB inhibitor. Our results revealed that the CSR/CP combined therapy (CCCT) attenuated colon shortening, DAI and MDI in addition to improvement of the colonic histological picture. Moreover, the CCCT increased the antioxidant defense machinery of the colonic tissue and decreased MPO activity. Furthermore, the inflammation markers such as TNF-α and IL-6 were downregulated. These effects might be attributed to the inhibitory effect of CSR on the priming step of the NLRP3 inflammasome activation by interrupting NF-κB signalling and inhibition of HSP-90 (at the protein and mRNA levels) along with inhibitory effect of CP on the expression of the NLRP3. These latter effects resulted in decreased tissue expression and activity of the caspase-1 and repressing the subsequent release of the active forms of IL-1β and IL-18, hence, the pyroptosis process is restrained. Additionally, the CCCT resulted in inducing autophagy by AMPK/mTOR-dependent mechanisms leading to the accumulation of BECN1 protein and a significant decrease in the levels of p62 SQSTM1. The inhibitory effect on HSP-90 in conjunction with induction of autophagy suggest increased autophagic degradation of NLRP3. This novel approach provides a basis for the clinical application of this combination in IBD treatment and might also be promising for the pharmacological intervention of other NLRP3 inflammasome-dependent inflammatory conditions.KOP-r agonist U50,488H produces strong aversion and anxiety/depression-like behaviors that enhance alcohol intake and promote alcohol seeking and relapse-like drinking in rodents. Mammalian target of rapamycin complex 1 (mTORC1) pathway in mouse striatum is highly involved in excessive alcohol intake and seeking, and in the U50,488H-induced conditioned place aversion. Therefore, we hypothesized that KOP-r activation increases alcohol consumption through the mTORC1 activation. This study focuses on (1) how chronic excessive alcohol drinking (4-day drinking-in-the-dark paradigm followed by 3-week chronic intermittent access drinking paradigm [two-bottle choice, 24-h access every other day]) affected nuclear transcript levels of the mTORC1 pathway genes in mouse nucleus accumbens shell (NAcs), using transcriptome-wide RNA sequencing analysis; and (2) whether selective mTORC1 inhibitor rapamycin could alter excessive alcohol drinking and prevent U50,488H-promoted alcohol intake. Thirteen nuclear transcripts of mTORC1 pathway genes showed significant up-regulation in the NAcs, with two genes down-regulated, after excessive alcohol drinking, suggesting the mTORC1 pathway was profoundly disrupted. Single administration of rapamycin decreased alcohol drinking in a dose-dependent manner. U50,488H increased alcohol drinking, and pretreatment with rapamycin, at a dose lower than effective doses, blocked the U50,488H-promoted alcohol intake in a dose-dependent manner, indicating a mTORC1-mediated mechanism. Our results provide supportive and direct evidence relevant to the transcriptional profiling of the critical mTORC1 genes in mouse NAc shell with functional and pharmacological effects of rapamycin, altered nuclear transcripts in the mTORC1 signaling pathway after excessive alcohol drinking may contribute to increased alcohol intake triggered by KOP-r activation.

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