Studio dei meccanismi molecolari coinvolti nell'attività antiproliferativa dell'olio essenziale di Pistacia lentiscus

Content Provider	Semantic Scholar
Author	Casarin, Elisabetta
Copyright Year	2011
Abstract	The phytocomplex from Pistacia lentiscus, a shrub of the Anacardiaceae family, is an essential oil obtained by hydrodistillation of leaves, fruits or from a trunk exudate (mastic gum). The mastic gum has been known to be effective in several gastric diseases, against Helicobacter Pylori and for its antibacterial and antifungine activities. Furthermore, Pistacia oil's major chemical constituents are monoterpenes with chemiopreventive and chemiotherapic properties. We investigated the antiproliferative properties of the volatile oil from Pistacia lentiscus twigs and leaves using human cell lines from ovarian (2008 and cis-platinum resistant, C13*) and colon (LoVo) adenocarcinoma, and human stable fibroblast line (HFFF2) as in vitro models. The MTT test showed that, after 3-hour treatment, phytocomplex (about 150 µg/ml) was able to inhibit the growth of all adenocarcinoma cell lines. After 24 hour treatment the IC50 on 2008 and LoVo cells resulted 3 times lower. On fibroblast line the phytocomplex was active only after 72 hour treatment. Western blotting analysis confirmed the oil capability to reduce carcinoma cell growth by decreasing the expression of p-ERK, MAPKs induced by mitogenic stimuli. In treated cells: vacuolisation, decreasing cellular size and brightness, directly proportional to reduction of cell viability, were observed by optical microscope. Using annexin V with propidium iodide we observed that oil was able to stimulate apoptosis in a dose-dependent manner. ROS has been recognized as an important mediator of the stress response; in particular, by regulating the loss of mitochondrial membrane potential. Furthermore upstream of ROS generation there is a respiratory chain block that leads even an increase of mitochondrial membrane potential. Analysis of mitochondrial membrane potential, with Rhodamine123, and ROS generation, with H2DCF-DA, showed the oil capability to activate mitochondrial apoptotic pathway. Oil-treatment also induced alteration on H+ gradient and interruption of electron flow between respiratory chain complexes III and IV, thereby causing loss of ATP. In the initiation of apoptosis caspases play critical roles. They can be grouped into "apoptotic initiators", for example caspase 8 and 9, and "apoptotic effectors", such as caspase 3, according to their substrate specificities and target proteins. Our data indicated that Pistacia lentiscus oil caused programmed cell death via a caspase-dependent pathway. In fact, after 3 hour treatment and 21 hour incubation, caspase 3 activity level, resulted higher than in the control, especially for the highest dose used. We also performed a flow cytometry-based cell cycle analysis, observing that the phytocomplex induced dose-dependent arrest in G2/M phase by decreasing cyclin B1 levels on all adenocarcinoma lines, especially on ovarian cells, and acting on acetylated tubulin and microtubules' polymerization/depolymerization.
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Alternate Webpage(s)	http://paduaresearch.cab.unipd.it/3663/1/TesiDottElisabetta.pdf
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article