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Updated: Jul 10, 2026
10:41
Detection of Toxin Translocation into the Host Cytosol by Surface Plasmon Resonance
Published on: January 3, 2012
Polyunsaturated fatty acids regulate Shiga toxin transport
Bjørn Spilsberg1, Alicia Llorente, Kirsten Sandvig
1Department of Biochemistry, Centre for Cancer Biomedicine, Institute for Cancer Research, Faculty Division The Norwegian Radium Hospital, University of Oslo, Montebello, N-0310 Oslo, Norway.
Biochemical and Biophysical Research Communications
|October 19, 2007
Summary
Polyunsaturated fatty acids (PUFA) significantly reduce Shiga toxin (Stx) and cholera toxin entry into cells. This finding highlights PUFA
Area of Science:
- Cell Biology
- Molecular Toxicology
- Biochemistry
Background:
- Shiga toxin (Stx) enters cells via endocytosis and moves retrogradely to the endoplasmic reticulum.
- The active component of Stx is translocated to the cytosol, causing cellular damage.
- Understanding toxin trafficking is crucial for developing therapeutic interventions.
Purpose of the Study:
- To investigate the impact of polyunsaturated fatty acids (PUFA) on Stx intoxication.
- To determine PUFA's effect on the retrograde transport of Stx.
- To assess if PUFA affects the internalization of other toxins.
Main Methods:
- HEp-2 cells were treated with PUFA.
- Stx intoxication levels were measured.
- Toxin internalization and transport to the Golgi apparatus were analyzed.
- Cytotoxicity assays were performed for ricin and Pseudomonas exotoxin 1.
Main Results:
- PUFA treatment inhibited Stx intoxication by 10-fold in HEp-2 cells.
- PUFA reduced both Stx internalization and endosome-to-Golgi transport.
- Cholera toxin internalization was also reduced by PUFA treatment.
- Ricin and Pseudomonas exotoxin 1 cytotoxicity remained unaffected by PUFA.
Conclusions:
- PUFA significantly inhibit Shiga toxin and cholera toxin intoxication.
- PUFA interfere with the cellular uptake and trafficking of these toxins.
- PUFA do not broadly block retrograde transport, indicating specificity for certain toxins.
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