Cellular responses associated with dibucaine-induced phospholipidosis
Ana Peropadre1, Paloma Fernández Freire, Oscar Herrero
1Cellular Toxicology Group, Laboratory A-110, C/Darwin 2, 28049 Madrid, Spain.
Chemical Research in Toxicology
|January 26, 2011
Summary
Cationic amphiphilic drugs can cause phospholipidosis, a cellular storage disorder. This study shows that while mild stress from these drugs triggers defense mechanisms like autophagy, excessive exposure leads to cell death, impacting drug safety assessment.
Area of Science:
- Cell Biology
- Pharmacology
- Toxicology
Background:
- Cationic amphiphilic drugs (CADs) induce phospholipidosis, a lipid storage disorder, across various therapeutic classes.
- The clinical relevance of CAD-induced phospholipidosis and its link to cellular toxicity remain unclear.
- Phospholipidosis is a significant concern in pharmaceutical drug development due to potential clinical side effects.
Purpose of the Study:
- To investigate cellular responses to drug-induced phospholipidosis.
- To determine the relationship between phospholipidosis and cellular toxicity.
- To examine the effects of dibucaine-induced phospholipidosis in cultured mammalian kidney cells.
Main Methods:
- Utilized Vero cells (mammalian kidney cells) for in vitro studies.
- Induced phospholipidosis using dibucaine, an amide-type anesthetic.
- Assessed cell viability, proliferation, and morphological changes using multiple assays.
- Monitored cellular defense responses including growth arrest and autophagy.
Main Results:
- Dibucaine induced lysosomal phospholipidosis in Vero cells.
- Mild stress conditions led to transient growth arrest and autophagy, indicating cellular defense mechanisms.
- Exceeding cellular tolerance limits resulted in irreversible injury and cell death.
- Phospholipidosis was associated with both adaptive cellular responses and overt toxicity depending on stress levels.
Conclusions:
- CAD-induced phospholipidosis can trigger cellular defense mechanisms under mild stress.
- Severe exposure to CADs leads to significant cellular injury and death, irrespective of phospholipidosis.
- Findings offer insights into drug safety assessment and the toxicological profile of CADs.
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