Beneficial effects of (RS)-glucoraphanin on the tight junction dysfunction in a mouse model of restraint stress

Life Sci. 2013 Aug 28;93(7):288-305. doi: 10.1016/j.lfs.2013.07.003. Epub 2013 Jul 16.

Abstract

Aims: The purpose of this work is to evaluate the effects of (RS)-glucoraphanin, a glucosinolate present in Brassicaceae, notably in Tuscan black kale, and bioactivated with myrosinase enzyme (bioactive RS-GRA) (10mg/kg intraperitoneally), and to assess its capacity to prevent the dysfunction of the blood-brain barrier (BBB), a fundamental structure for brain homeostasis, in a mouse model of restraint stress.

Main methods: CD1 mice were subjected to restraint stress by blocking the body with a tape on a table for 150 min at the four extremities. After the sacrifice of the animals, stomachs and brains were collected to perform histological evaluation, Evan's blue dye, immunohistochemistry and western blotting analysis, to evaluate whether immobilization stress leads to alterations of tight junction (TJ) components, such as claudin-1, claudin-3 and ZO-1.

Key findings: Immobilization causes considerable damage to BBB as shown by detection of Evan's blue dye, indicating a high level of extravasation due to stress. BBB alterations were accompanied by an enhancement of GFAP expression, IkB-alpha degradation followed by increased NF-kBp65 nuclear translocation, as well as caspase 3 overexpression. Conversely, our results revealed that bioactive RS-GRA treatment significantly counteracts the changes in all these parameters and preserves TJ integrity reducing the production of pro-inflammatory cytokines, such as TNF-α and IL-1β, and increasing the production of IL-10, an anti-inflammatory cytokine. Additionally, bioactive RS-GRA shows antioxidant properties modulating iNOS and nitrotyrosine expression.

Significance: Our results clearly show that bioactive RS-GRA could represent a possible treatment during pharmacological therapy of stress.

Keywords: Blood–brain barrier; Claudins; R(S)-glucoraphanin; Restraint stress; Tight junctions; ZO-1.

MeSH terms

  • Animals
  • Blood-Brain Barrier / drug effects
  • Caspase 3 / metabolism
  • Claudins / metabolism
  • Coloring Agents
  • Cytokines / metabolism
  • Enzyme Activation / drug effects
  • Evans Blue
  • GA-Binding Protein Transcription Factor / metabolism
  • Glial Fibrillary Acidic Protein / metabolism
  • Glucosinolates / pharmacology*
  • Glycoside Hydrolases / isolation & purification
  • Glycoside Hydrolases / metabolism
  • Imidoesters / pharmacology*
  • Mice
  • Nitric Oxide Synthase Type II / metabolism
  • Oximes
  • Restraint, Physical
  • Stress, Psychological / drug therapy*
  • Stress, Psychological / pathology*
  • Sulfoxides
  • Tight Junctions / drug effects*
  • Tight Junctions / pathology*
  • Transcription Factor RelA / metabolism
  • Tyrosine / analogs & derivatives
  • Tyrosine / metabolism

Substances

  • Claudins
  • Coloring Agents
  • Cytokines
  • GA-Binding Protein Transcription Factor
  • Gabpa protein, mouse
  • Glial Fibrillary Acidic Protein
  • Glucosinolates
  • Imidoesters
  • Oximes
  • Sulfoxides
  • Transcription Factor RelA
  • 3-nitrotyrosine
  • Tyrosine
  • Evans Blue
  • Nitric Oxide Synthase Type II
  • Glycoside Hydrolases
  • thioglucosidase
  • Caspase 3
  • glucoraphanin