Article

Antitumor effects of two novel naturally occurring terpene quinones isolated from the Mediterranean ascidian Aplidium conicum.

Dipartimento di Chimica delle Sostanze Naturali, Universitá degli Studi di Napoli Federico II, Via Domenico Montesano n. 49-80131, Napoli, Italy.
Journal of Medicinal Chemistry (impact factor: 5.25). 06/2005; 48(9):3410-6. DOI:10.1021/jm0489915 pp.3410-6
Source: PubMed

ABSTRACT The ascidian Aplidium conicum collected along Sardinia coasts (Italy) contained two novel prenylated benzoquinones, designated thiaplidiaquinone A (1) and thiaplidiaquinone B (2). These compounds showed an unprecedented tetracyclic structure. We have studied the pro-apototic mechanisms of both prenylated benzoquinones in the Jurkat cell line that is derived from a human T lymphoma, and we show that both compounds induce a strong production of intracellular reactive oxygen species (ROS) in this cell line. Moreover, kinetic experiments, comparing the timing of ROS induction with the collapse of the mitochondria potential (DeltaPsi(m)), clearly showed that ROS preceded the disruption of the mitochondrial potential, and the later one paralleled the appearance of apoptotic cells. Thus, thiaplidiaquinones A and B can enter into the cells and induce cell death by apoptosis.

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Keywords

apoptosis
 
ascidian Aplidium conicum
 
compounds induce
 
disruption
 
human T lymphoma
 
induce cell death
 
intracellular reactive oxygen species
 
Italy
 
Jurkat cell line
 
kinetic experiments
 
mitochondria potential
 
mitochondrial potential
 
novel prenylated benzoquinones
 
one paralleled
 
prenylated benzoquinones
 
pro-apototic mechanisms
 
ROS induction
 
Sardinia coasts
 
thiaplidiaquinone B
 
unprecedented tetracyclic structure