Borna Disease Virus Infection Perturbs Energy Metabolites and Amino Acids in Cultured Human Oligodendroglia Cells

Abstract

BackgroundBorna disease virus is a neurotropic, non-cytolytic virus that has been widely employed in neuroscientific research. Previous studies have revealed that metabolic perturbations are associated with Borna disease viral infection. However, the pathophysiological mechanism underlying its mode of action remains unclear.MethodologyHuman oligodendroglia cells infected with the human strain Borna disease virus Hu-H1 and non-infected matched control cells were cultured in vitro. At day 14 post-infection, a proton nuclear magnetic resonance-based metabonomic approach was used to differentiate the metabonomic profiles of 28 independent intracellular samples from Borna disease virus-infected cells (n = 14) and matched control cells (n = 14). Partial least squares discriminant analysis was performed to demonstrate that the whole metabonomic patterns enabled discrimination between the two groups, and further statistical testing was applied to determine which individual metabolites displayed significant differences between the two groups.FindingsMetabonomic profiling revealed perturbations in 23 metabolites, 19 of which were deemed individually significant: nine energy metabolites (α-glucose, acetate, choline, creatine, formate, myo-inositol, nicotinamide adenine dinucleotide, pyruvate, succinate) and ten amino acids (aspartate, glutamate, glutamine, glycine, histidine, isoleucine, phenylalanine, threonine, tyrosine, valine). Partial least squares discriminant analysis demonstrated that the whole metabolic patterns enabled statistical discrimination between the two groups.ConclusionBorna disease viral infection perturbs the metabonomic profiles of several metabolites in human oligodendroglia cells cultured in vitro. The findings suggest that Borna disease virus manipulates the host cell’s metabolic network to support viral replication and proliferation.

Persistent human Borna disease virus infection modifies the acetylome of human oligodendroglia cells towards higher energy and transporter levels

“…In addition, the metabolism of several amino acids (i.e., betaalanine, tryptophan, lysine, valine, leucine, and isoleucine) was also significantly enriched in the high SILAC L/H ratio quantile, supporting previous metabonomic data (Huang et al, 2012). BDV affects amino acid metabolism through an acetylation-based mechanism.…”

“…In addition, the metabolism of several amino acids (i.e., betaalanine, tryptophan, lysine, valine, leucine, and isoleucine) was also significantly enriched in the high SILAC L/H ratio quantile, corresponding to elevated alanine, valine, and isoleucine levels previously reported in our metabonomic study (Huang et al, 2012).…”

“…This is particularly known for large DNA viruses like herpes viruses which are able to actively redirect their host cells' energy metabolism and significantly perturb glycolysis, TCA cycle, and pentose phosphate pathway intermediates (Vastag et al, 2011). In terms of BDV which is less than 10 times the size of herpes viruses, the most significantly altered pathways were those linked to energy metabolism, as shown in previous studies of our group (Huang et al, 2012;Liu et al, 2014aLiu et al, , 2014b. In line with these findings, we could demonstrate here that acetylation levels of specific Kac sites of six proteins involved in butanoate metabolism (i.e., K174 on ACAT1, K118 on ECHS1, K317 on HADH, K48 on HMGCL, K463 on OXCT1 and K101 on PDHA1) were increased in response to BDV infection.…”

“…In brief, OL cells were sub-cultured in one 10-cm dish and washed twice with serum-free DMEM prior to infection with BDV Hu-H1 stock solution at a multiplicity of infection (MOI) of 1.0 (800 μl) (Huang et al, 2012). Cells were then stored in a humidified incubator (5% CO 2 , 37 1C) for two hours with gentle shaking for 15 min.…”

Identification of suitable reference genes for BDV-infected primary rat hippocampal neurons

“…To identify the purity of neurons and the effect of BDV infection for each experiment, a standard immunofluorescence protocol was used, as previously described (14,15) and observed with a fluorescence microscope (Nikon Corporation, Tokyo, Japan). Briefly, the BDV-infected and non-infected neurons were incubated in six-well plates for 20 min at room temperature with 4% paraformaldehyde, followed by permeabilization for 10 min in 0.25% Triton X-100.…”