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Trypanosoma cruzi Epimastigotes Are Able to Manage Internal Cholesterol Levels under Nutritional Lipid Stress Conditions.

Pereira MG, Visbal G, Salgado LT, Vidal JC, Godinho JL, De Cicco NN, Atella GC, de Souza W, Cunha-e-Silva N - PLoS ONE (2015)

Bottom Line: Moreover, the parasites were able to manage internal cholesterol levels, alternating between consumption and accumulation.With normal lipid availability, parasites esterified cholesterol exhibiting an ACAT-like activity that was sensitive to Avasimibe in a dose-dependent manner.This result also implies that exogenous cholesterol has a role in lipid reservoirs in epimastigotes.

View Article: PubMed Central - PubMed

Affiliation: Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil; Laboratório de Bioquímica de Lipídios e Lipoproteínas, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil.

ABSTRACT
Trypanosoma cruzi epimastigotes store high amounts of cholesterol and cholesteryl esters in reservosomes. These unique organelles are responsible for cellular digestion by providing substrates for homeostasis and parasite differentiation. Here we demonstrate that under nutritional lipid stress, epimastigotes preferentially mobilized reservosome lipid stocks, instead of lipid bodies, leading to the consumption of parasite cholesterol reservoirs and production of ergosterol. Starved epimastigotes acquired more LDL-NBD-cholesterol by endocytosis and distributed the exogenous cholesterol to their membranes faster than control parasites. Moreover, the parasites were able to manage internal cholesterol levels, alternating between consumption and accumulation. With normal lipid availability, parasites esterified cholesterol exhibiting an ACAT-like activity that was sensitive to Avasimibe in a dose-dependent manner. This result also implies that exogenous cholesterol has a role in lipid reservoirs in epimastigotes.

No MeSH data available.


Related in: MedlinePlus

Incorporation of 3H-cholesterol into cholesteryl esters in epimastigotes.Parasites were incubated in LIT medium with 10% FCS (control) or 10% dFCS (starved) in the presence of LDL-3H-cholesterol (1,000,000 DPM; 2 mg/mL) for 3 days at 28°C. Parasites were washed and their lipids were extracted and analysed by TLC. The cholesterol (CHO) and cholesteryl-ester (CHOE) spots were scraped and the lipid eluted from silica. The lipid-associated radioactivity was measured by liquid scintillation counting. The results are expressed as the mean (±SD) per 1 mg of protein of three independent experiments analysed by one-way ANOVA followed by the Bonferroni test (*P<0.05).
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pone.0128949.g004: Incorporation of 3H-cholesterol into cholesteryl esters in epimastigotes.Parasites were incubated in LIT medium with 10% FCS (control) or 10% dFCS (starved) in the presence of LDL-3H-cholesterol (1,000,000 DPM; 2 mg/mL) for 3 days at 28°C. Parasites were washed and their lipids were extracted and analysed by TLC. The cholesterol (CHO) and cholesteryl-ester (CHOE) spots were scraped and the lipid eluted from silica. The lipid-associated radioactivity was measured by liquid scintillation counting. The results are expressed as the mean (±SD) per 1 mg of protein of three independent experiments analysed by one-way ANOVA followed by the Bonferroni test (*P<0.05).

Mentions: In order to investigate the ability of epimastigotes to esterify cholesterol, the parasites were maintained in LIT medium plus 10% FCS or dFCS, supplemented with 3H-cholesterol-LDL for 3 days at 28°C. Fig 4 shows that control parasites esterified four-fold more cholesterol than starved epimastigotes. The lower rate of cholesterol esterification in starved parasites highlights the fact that these parasites, when deprived of lipids for a long time, used the previous stock of exogenous lipids in their immediate metabolism, most likely to restore and maintain membrane production for proliferation. The modulation of the production of cholesteryl esters by cholesterol availability is similar to that found in mammalian cells [30], with the important difference being that the endocytic uptake is the only cholesterol source.


Trypanosoma cruzi Epimastigotes Are Able to Manage Internal Cholesterol Levels under Nutritional Lipid Stress Conditions.

Pereira MG, Visbal G, Salgado LT, Vidal JC, Godinho JL, De Cicco NN, Atella GC, de Souza W, Cunha-e-Silva N - PLoS ONE (2015)

Incorporation of 3H-cholesterol into cholesteryl esters in epimastigotes.Parasites were incubated in LIT medium with 10% FCS (control) or 10% dFCS (starved) in the presence of LDL-3H-cholesterol (1,000,000 DPM; 2 mg/mL) for 3 days at 28°C. Parasites were washed and their lipids were extracted and analysed by TLC. The cholesterol (CHO) and cholesteryl-ester (CHOE) spots were scraped and the lipid eluted from silica. The lipid-associated radioactivity was measured by liquid scintillation counting. The results are expressed as the mean (±SD) per 1 mg of protein of three independent experiments analysed by one-way ANOVA followed by the Bonferroni test (*P<0.05).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4466137&req=5

pone.0128949.g004: Incorporation of 3H-cholesterol into cholesteryl esters in epimastigotes.Parasites were incubated in LIT medium with 10% FCS (control) or 10% dFCS (starved) in the presence of LDL-3H-cholesterol (1,000,000 DPM; 2 mg/mL) for 3 days at 28°C. Parasites were washed and their lipids were extracted and analysed by TLC. The cholesterol (CHO) and cholesteryl-ester (CHOE) spots were scraped and the lipid eluted from silica. The lipid-associated radioactivity was measured by liquid scintillation counting. The results are expressed as the mean (±SD) per 1 mg of protein of three independent experiments analysed by one-way ANOVA followed by the Bonferroni test (*P<0.05).
Mentions: In order to investigate the ability of epimastigotes to esterify cholesterol, the parasites were maintained in LIT medium plus 10% FCS or dFCS, supplemented with 3H-cholesterol-LDL for 3 days at 28°C. Fig 4 shows that control parasites esterified four-fold more cholesterol than starved epimastigotes. The lower rate of cholesterol esterification in starved parasites highlights the fact that these parasites, when deprived of lipids for a long time, used the previous stock of exogenous lipids in their immediate metabolism, most likely to restore and maintain membrane production for proliferation. The modulation of the production of cholesteryl esters by cholesterol availability is similar to that found in mammalian cells [30], with the important difference being that the endocytic uptake is the only cholesterol source.

Bottom Line: Moreover, the parasites were able to manage internal cholesterol levels, alternating between consumption and accumulation.With normal lipid availability, parasites esterified cholesterol exhibiting an ACAT-like activity that was sensitive to Avasimibe in a dose-dependent manner.This result also implies that exogenous cholesterol has a role in lipid reservoirs in epimastigotes.

View Article: PubMed Central - PubMed

Affiliation: Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil; Laboratório de Bioquímica de Lipídios e Lipoproteínas, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil.

ABSTRACT
Trypanosoma cruzi epimastigotes store high amounts of cholesterol and cholesteryl esters in reservosomes. These unique organelles are responsible for cellular digestion by providing substrates for homeostasis and parasite differentiation. Here we demonstrate that under nutritional lipid stress, epimastigotes preferentially mobilized reservosome lipid stocks, instead of lipid bodies, leading to the consumption of parasite cholesterol reservoirs and production of ergosterol. Starved epimastigotes acquired more LDL-NBD-cholesterol by endocytosis and distributed the exogenous cholesterol to their membranes faster than control parasites. Moreover, the parasites were able to manage internal cholesterol levels, alternating between consumption and accumulation. With normal lipid availability, parasites esterified cholesterol exhibiting an ACAT-like activity that was sensitive to Avasimibe in a dose-dependent manner. This result also implies that exogenous cholesterol has a role in lipid reservoirs in epimastigotes.

No MeSH data available.


Related in: MedlinePlus