Gene expression comparison reveals distinct basal expression of HOX members and differential TNF-induced response between brain- and spinal cord-derived microvascular endothelial cells

Abstract

BackgroundThe heterogeneity of endothelial cell types underlies their remarkable ability to sub-specialize and provide specific requirements for a given vascular bed. Here, we compared rat microvascular endothelial cells (MECs) derived from the brain and spinal cord in both basal and inflammatory conditions.MethodsWe used whole rat genome microarrays to compare, at different time points, basal and TNF-α-induced gene expression of rat MECs from in vitro models of the blood-brain barrier (BBB) and blood-spinal cord barrier (BSCB). Validation at both messenger RNA (mRNA) and protein levels was performed on freshly extracted microvessels (MVs) from the brain and spinal cord (BMVs and SCMVs, respectively), as these were considered the closest in vivo tissues to cultured MECs.ResultsMost of the genes encoding adhesion/tight junction molecules and known endothelial markers were similarly expressed in brain and spinal cord MECs (BMECs and SCMECs, respectively). However, one striking finding was the higher expression of several Hox genes, which encode transcription factors involved in positional identity. The differential expression of Hoxa9 and Hoxb7 at the mRNA levels as well as protein levels was confirmed in BMVs and SCMVs. Although the TNF-α response was in general higher in BMECs than in SCMECs at 12 h, the opposite was observed at 48 h. Furthermore, we found that expression of Tnfrsf1a and Tnfrsf1b encoding the TNF receptor super-family member 1a/TNFR1 and 1b/TNFR2, respectively, were constitutively higher in BMVs compared to SCMVs. However, only Tnfrsf1b was induced in SCMECs in response to TNF-α at 24 and 48 h.ConclusionsOur results support a role for HOX members in defining the positional identities of MECs in vivo. Our data also suggest that the delayed transcriptional activation upon TNF-α treatment in SCMECs results from the requirement of the TNF-induced expression of Tnfrsf1b. In contrast, its high basal expression in BMECs might be sufficient to confer an immediate and efficient TNF-α response.Electronic supplementary materialThe online version of this article (doi:10.1186/s12974-016-0749-6) contains supplementary material, which is available to authorized users.

Human ES-derived MSCs correct TNF-α-mediated alterations in a blood–brain barrier model

“…And CXCL12 purportedly acts in a negative capacity to retain infiltrating leukocytes in the perivascular space during MS [120, 121]. Figure 6 reveals TNF-α stimulation of BMECs caused up-regulation of CCL2 gene expression, in accord with prior reports of elevated CCL2 release [124] and mRNA level [113, 125] following TNF-α treatment. In opposite fashion, TNF-α stimulation decreased CXCL12 gene expression by BMECs, paralleling the response seen after stimulation with another pro-inflammatory substance: LPS [126].…”

“…Thus, further experiments evaluated whether hES-MSCs could correct any alterations in gene expression of both these adhesions molecules. Figure 5 shows TNF-α treatment caused significant up-regulation of ICAM-1 and VCAM expression by BMEC, reaffirming the inflammatory phenotype induced in these cells by pro-inflammatory cytokine exposure [113–117]. Application of hES-MSCs reversed the up-regulation of both adhesion molecules, and was effective irrespective of being placed in the top or bottom chamber.…”

<p>Integrative analysis of the lncRNA-associated ceRNA network reveals lncRNAs as potential prognostic biomarkers in human muscle-invasive bladder cancer</p>

“…HOXC13, a member of the homeobox HOXC gene family, has been reported to correlate with the development of cancers such as colon cancer,39 esophageal squamous cell carcinoma40 and skin tumors 41. HOXC13 promotes proliferation and inhibits apoptosis in cancers by regulating numerous biological processes and signaling pathways, including the EMT42 and TNF signaling pathway 43. Based on this indirect evidence, MIR137HG functions as an lncRNA-associated ceRNA to promote the progression of MIBC by regulating the expression of miR-31-5p and HOXC13.…”

Long-Term Pantethine Treatment Counteracts Pathologic Gene Dysregulation and Decreases Alzheimer's Disease Pathogenesis in a Transgenic Mouse Model

“…A significant number of these genes (Table 1) were reported in our previous temporal gene profiling study (27) and are known to be related to glial activation and neuroinflammation in an AD context. Figure 5 shows the relationships between these genes and related AD activities identified through a bibliographic search using PredictSearch software (27,39). Indeed, most of these activities highlight the role of the selected genes in astroglial activation (Gfap, S100a6), microglial activation (Aif1/Iba1, CD68, Hexb2) and phagocytosis (Cd14, Trem2, Tyrobp, Csf1r, C1qa, C1qb, C1qc, C4a, and C4b).…”