Related Experiment Video
Updated: May 3, 2026
Development of Leishmania Species Strains with Constitutive Expression of eGFP
Published on: April 21, 2023
Frequency of MDR1-related p-gp overexpression in Greek Leishmania isolates
Johannes Austrup1, Pantelis Ntais, Vasiliki Christodoulou
1Center of Anatomy, Institute II, Laboratory for Medical and Molecular Parasitology, Medical School, University of Cologne, Cologne, Germany, johannesaustrup@gmail.com.
Abstract:
In this work, we investigated Greek Leishmania isolates (n = 70) for their individual MDR1-gene-related p-gp (belonging to the ABC-B subfamily of permeases) expression levels by means of flow cytometric analysis of Rhodamine 123 extrusion kinetics. Of all used isolates, 5.71% express this drug-extruding ABC-transporter at alarming levels and are distributed widely over the country. Some 33% of all examined isolates originated on the island of Crete though none of the strains showed vastly elevated p-gp extrusion activity, indicating a reasonable implementation of anti-leishmanial compounds in this part of the country. Compared to isolates obtained from canine tissue, human Leishmania isolates were superior both in size and in subcellular differentiation in flow cytometry. Furthermore, a specific t test confirmed verapamil hydrochloride to be a highly potent p-gp reversal agent with p < 0.0001. In a second test series, the loading of Leishmania with Rhodamine 123 was moreover reduced when occurring under influence of verapamil hydrochloride, a known p-gp reversal agent, indicating an ATP-dependant influx of the fluorescent dye and therewith the drug itself. In a final, third experiment series, it was shown that Sb(V) does not act upon the promastigote form of Leishmania.
Insights
High levels of the drug-efflux pump P-glycoprotein (P-gp) were found in 5.71% of Greek Leishmania isolates. Verapamil hydrochloride effectively reversed P-gp activity, suggesting potential therapeutic strategies.
Area of Science:
- Parasitology
- Molecular Biology
- Pharmacology
Background:
- Leishmania parasites are a significant global health concern.
- Drug resistance, particularly P-glycoprotein (P-gp) mediated efflux, is a major challenge in treating leishmaniasis.
- Understanding P-gp expression in Leishmania isolates is crucial for developing effective therapies.
Purpose of the Study:
- To investigate the expression levels of MDR1-gene-related P-gp in Greek Leishmania isolates.
- To evaluate the efficacy of verapamil hydrochloride as a P-gp reversal agent.
- To assess the impact of Sb(V) on Leishmania promastigotes.
Main Methods:
- Flow cytometric analysis of Rhodamine 123 extrusion kinetics to measure P-gp activity.
- Statistical analysis (t-test) to confirm verapamil hydrochloride's potency.
- Experimental assessment of Sb(V) effects on Leishmania promastigotes.
Main Results:
- 5.71% of Greek Leishmania isolates exhibited high P-gp expression, distributed nationwide.
- Leishmania isolates from Crete showed no significantly elevated P-gp activity.
- Verapamil hydrochloride was confirmed as a potent P-gp reversal agent (p < 0.0001), reducing Rhodamine 123 uptake.
- Sb(V) did not affect the promastigote form of Leishmania.
Conclusions:
- A subset of Greek Leishmania isolates possesses high P-gp expression, potentially contributing to drug resistance.
- Verapamil hydrochloride shows promise as an adjunct therapy to overcome P-gp-mediated drug efflux.
- Further research is needed to explore the therapeutic implications of these findings.
More Related Videos
10:01Quantification of Intracellular Growth Inside Macrophages is a Fast and Reliable Method for Assessing the Virulence of Leishmania Parasites
Published on: March 16, 2018
08:17Deciphering the Molecular Mechanism and Function of Pore-Forming Toxins Using Leishmania major
Published on: October 28, 2022
