U18666A Treatment Results in Cholesterol Accumulation, Reduced Na(+), K(+)-ATPase Activity, and Increased Oxidative Stress in Rat Cortical Astrocytes.
The objective of this study was to determine the effect of U18666A, an inhibitor of cholesterol synthesis and its intracellular transport, on oxidative stress parameters in cortical astrocytes cultured from Wistar rats (0-3 days old). The cultures were incubated with U18666A (0.25 µg/mL) for 48 h, conditions that are considered ideal to mimic Niemann-Pick type C disease. A variety of indicators of oxidative stress were measured. U18666A treatment increased cholesterol 2-fold in treated compared to control astrocytes. Oxidative stress was significantly elevated in treated cells as demonstrated by a 1.7-fold increase in thiobarbituric acid reactive substances, a 60% decrease is sulfhydral groups, and a 3.7-fold increase in carbonyl groups, indicative of increased lipid and protein oxidation following U18666A treatment. Consistent with these changes, both catalase and superoxide dismutase activities were significantly reduced nearly 50% in treated compared to control astrocytes. Collectively, these change resulted in a 50% reduction in Na(+), K(+)-ATPase specific activity following U18666A treatment, suggesting a significant alteration in its plasma membrane environment. Overall, these changes indicate that U18666A treatment results in increased cholesterol levels and an increased level of oxidative stress in cortical astrocytes, consistent with what is observed in Niemann-Pick type C disease.
Biochemistry Department, Lysosomal Storage Diseases Laboratory, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil. danielacopetti@yahoo.com.br.
Daniela
D
Copetti-Santos
Biochemistry Department, Lysosomal Storage Diseases Laboratory, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Vitoria
V
Moraes
Biochemistry Department, Lysosomal Storage Diseases Laboratory, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Dácio Franco
DF
Weiler
Biosciences and Rehabilitation, Centro Universitário Metodista (IPA), Porto Alegre, RS, Brazil.
Alexandre Silva
AS
de Mello
Biosciences and Rehabilitation, Centro Universitário Metodista (IPA), Porto Alegre, RS, Brazil.
Fernanda de Souza
Fde S
Machado
Biosciences and Rehabilitation, Centro Universitário Metodista (IPA), Porto Alegre, RS, Brazil.
Jéssica Pereira
JP
Marinho
Biochemistry Department, Metabolic Diseases and Neuroprotection Laboratory, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Cassiana
C
Siebert
Biochemistry Department, Metabolic Diseases and Neuroprotection Laboratory, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Janaina
J
Kolling
Biosciences and Rehabilitation, Centro Universitário Metodista (IPA), Porto Alegre, RS, Brazil.
Cláudia
C
Funchal
Biochemistry Department, Metabolic Diseases and Neuroprotection Laboratory, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Angela T S
AT
Wyse
Biochemistry Department, Metabolic Diseases and Neuroprotection Laboratory, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Janice Carneiro
JC
Coelho
D000736:Androstenes / Q000494:pharmacology*; D000818:Animals; D000924:Anticholesteremic Agents / Q000494:pharmacology*; D001253:Astrocytes / Q000187:drug effects*; D002374:Catalase / Q000378:metabolism; D002478:Cells, Cultured; D002784:Cholesterol / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D051381:Rats; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism
D000736:Androstenes; D000924:Anticholesteremic Agents; C006261:3-beta-(2-(diethylamino)ethoxy)androst-5-en-17-one; D002784:Cholesterol; D002374:Catalase; D013482:Superoxide Dismutase; D000254:Sodium-Potassium-Exchanging ATPase
Astrocytes; Niemann–Pick type C disease; Oxidative stress; U18666A