Evaluation of expression and function of the H+/myo-inositol transporter HMIT;

BACKGROUND: The phosphoinositide (PIns) signalling pathway regulates a series of neuronal processes, such as neurotransmitter release, that are thought to be altered in mood disorders. Furthermore, mood-stabilising drugs have been shown to inhibit key enzymes that regulate PIns production and alter neuronal growth cone morphology in an inositol-reversible manner. Here, we describe analyses of expression and function of the recently identified H+/myo-inositol transporter (HMIT) investigated as a potential regulator of PIns signalling. RESULTS: We show that HMIT is primarily a neuronal transporter widely expressed in the rat and human brain, with particularly high levels in the hippocampus and cortex, as shown by immunohistochemistry. The transporter is localised at the Golgi apparatus in primary cultured neurones. No HMIT-mediated electrophysiological responses were detected in rat brain neurones or slices; in addition, inositol transport and homeostasis were unaffected in HMIT targeted null-mutant mice. CONCLUSION: Together, these data do not support a role for HMIT as a neuronal plasma membrane inositol transporter, as previously proposed. However, we observed that HMIT can transport inositol triphosphate, indicating unanticipated intracellular functions for this transporter that may be relevant to mood control

Dataset supporting the University of Southampton Doctoral Thesis "Development of poly(lactic-co-glycolic acid) electrospun membranes for incorporation into 3-D co-culture models of the airway-blood barrier"

Dataset supporting the University of Southampton Doctoral Thesis &quot;Development of poly(lactic-co-glycolic acid) electrospun membranes for incorporation into 3-D co-culture models of the airway-blood barrier&quot; This dataset contains raw data and associated graphs and statistics in GraphPad Prism (version 10.2.0) files. Separate files are included for each results chapter. Thesis_R1 - data for figures in the first results chapter, thesis chapter 3 - Development of an Electrospinning System and the Generation of PLGA Membranes THesis_R2 - data for figures in the second results chapter, thesis chapter 4 - Biological characterisation of Epithelial Barrier Formation on Electrospun PLGA Membranes Thesis_R3 - data for figures in the third results chapter, thesis chapter 5 - Development of a 3-D Co-culture Model using Electrospun Membrane Data collection as described in associated thesis. Statistics are included with the data entry. Software required to open filed: Graphpad Prism v10.2.0 (392) The data is embargoed until 20/01/2025. </span

Membrane lipid composition of bronchial epithelial cells influences antiviral responses during rhinovirus infection

Lipids and their mediators have important regulatory functions in many cellular processes, including the innate antiviral response. The aim of this study was to compare the lipid membrane composition of in vitro differentiated primary bronchial epithelial cells (PBECs) with ex vivo bronchial brushings and to establish whether any changes in the lipid membrane composition affect antiviral defence of cells from donors without and with severe asthma. Using mass spectrometry, we showed that the lipid membrane of in vitro differentiated PBECs was deprived of polyunsaturated fatty acids (PUFAs) compared to ex vivo bronchial brushings. Supplementation of the culture medium with arachidonic acid (AA) increased the PUFA-content to more closely match the ex vivo membrane profile. Rhinovirus (RV16) infection of AA-supplemented cultures from healthy donors resulted in significantly reduced viral replication while release of inflammatory mediators and prostaglandin E2 (PGE2) was significantly increased. Indomethacin, an inhibitor of prostaglandin-endoperoxide synthases, suppressed RV16-induced PGE2 release and significantly reduced CXCL-8/IL-8 release from AA-supplemented cultures indicating a link between PGE2 and CXCL8/IL-8 release. In contrast, in AA-supplemented cultures from severe asthmatic donors, viral replication was enhanced whereas PTGS2 expression and PGE2 release were unchanged and CXCL8/IL-8 was significantly reduced in response to RV16 infection.While the PTGS2/COX-2 pathway is initially pro-inflammatory, its downstream products can promote symptom resolution. Thus, reduced PGE2 release during an RV-induced severe asthma exacerbation may lead to prolonged symptoms and slower recovery. Our data highlight the importance of reflecting the in vivo lipid profile in in vitro cell cultures for mechanistic studies