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Lipopolysaccharide enters the rat brain by a lipoprotein-mediated transport mechanism in physiological conditions.

ABSTRACT: Physiologically, lipopolysaccharide (LPS) is present in the bloodstream and can be bound to several proteins for its transport (i.e.) LPS binding protein (LBP) and plasma lipoproteins). LPS receptors CD14 and TLR-4 are constitutively expressed in the Central Nervous System (CNS). To our knowledge, LPS infiltration in CNS has not been clearly demonstrated. A naturalistic experiment with healthy rats was performed to investigate whether LPS is present with its receptors in brain. Immunofluorescences showed that lipid A and core LPS were present in circumventricular organs, choroid plexus, meningeal cells, astrocytes, tanycytes and endothelial cells. Co-localization of LPS regions with CD14/TLR-4 was found. The role of lipoprotein receptors (SR-BI, ApoER2 and LDLr) in the brain as targets for a LPS transport mechanism by plasma apolipoproteins (i.e. ApoAI) was studied. Co-localization of LPS regions with these lipoproteins markers was observed. Our results suggest that LPS infiltrates in the brain in physiological conditions, possibly, through a lipoprotein transport mechanism, and it is bound to its receptors in blood-brain interfaces.

SUBMITTER: Vargas-Caraveo A

PROVIDER: S-EPMC5640642 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Lipopolysaccharide enters the rat brain by a lipoprotein-mediated transport mechanism in physiological conditions.

Vargas-Caraveo Alejandra A Sayd Aline A Maus Sandra R SR Caso Javier R JR Madrigal José L M JLM García-Bueno Borja B Leza Juan C JC

Scientific reports 20171013 1

Physiologically, lipopolysaccharide (LPS) is present in the bloodstream and can be bound to several proteins for its transport (i.e.) LPS binding protein (LBP) and plasma lipoproteins). LPS receptors CD14 and TLR-4 are constitutively expressed in the Central Nervous System (CNS). To our knowledge, LPS infiltration in CNS has not been clearly demonstrated. A naturalistic experiment with healthy rats was performed to investigate whether LPS is present with its receptors in brain. Immunofluorescenc ...[more]

PMID: 29030613

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Lipopolysaccharide enters the rat brain by a lipoprotein-mediated transport mechanism in physiological conditions.

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Lipopolysaccharide enters the rat brain by a lipoprotein-mediated transport mechanism in physiological conditions.

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