ln vitro analysis of the effects of radiofrequency radiations on autophagy processes
Abstract
——————————————————-
The purpose of this project is to analyze the effects of radiofrequency radiations (RFR) on the processes of autophagy, a major cellular system of protein and organelle degradation and recycling. This analysis will be performed using cell cultures of two cell types of the central nervous system: cortical neurons and astroglial cells. ln addition, we will examine : 1)- Whether cell pre-exposure to RFR sensitizes or renders cells resistant to an additional stress (e.g to avtrigger of apoptosis), 2)- Whether these (possible) modifications of cell sensitivity involve autophagy and 3)- Whether protein ubiquitination is affected by exposure to RFR.
——————————————————-
Partners
EA 3842 – Faculty of medicine – Limoges
XLIM
Faculty of sciences – Limoges
Contact
Faraj Terro
Faculty of medicine – University of Limoges
Laboratory of Histology and Cell Biology-EA 3842
Duration
24 months
Summary
——————————————————-
1) Introduction
Autophagy is the major mechanism for degrading and recycling of long-lived proteins and organelles in the lysosome pathway. Macroautophagy is the most common form of auto-phagy and is commonly referred to as “autophagy”. In response to a variety of insults, such as nutriment and growth factor deprivation, autophagy can be induced allowing the recycling of cytoplasmic constituents and promote cell survival. Autophagy plays a crucial role in the development and morphogenesis. Conversely, when autophagy is up-regulated, it could contribute to a form of cell death, the autophagie cell death. Abnormalities in autophagy might also lead to aggregations of abnormal proteins, a pathological hallmark of some neurodegenerative diseases including Alzheimer’s and Parkinson’s diseases. Moreover, alterations in autophagy could contribute to cell resistance and tumorogenesis.
Field and key words: Cell Biology, ln vitro, autophagy, GSM, neurons, astroglial cell, nervous system.
2) State of the art
Nowadays there are no available data concerning the effects of RFR on autophagy. ln addition, the originality of the present project is that it combines exposure to RFR with a delayed application of an additional well characterized stress.
3) Scientific methodology
This project is aimed at determining whether exposure to GSM 900 MHz radiofrequency radiations alters, in vitro, the processes of autophagy. For this purpose, cultured cortical neu-rons (post-mitotic cells) and astroglial cells (mitotic cells) (both at day 7) will be obtained from brains of rat fetus (E17-18). They will be exposed, in a wire-patch cell, to various SAR ranging from 0.02 à 6 W/kg during 24h or to one SAR (2 W/kg) for 8, 16 and 24h. A quantitative and qualitative analysis of autophagy will be performed by electronic microscopy, immunofluorescence and western blot, using antibodies directed against protein markers of autophagy (Beclin-1 expression, MAP-LC3 conversion,…). ln addition, we will examine, on one hand, whether cell pre-exposure to RFR sensitizes or renders cells resistant to an additional stress (e.g a trigger of apoptosis), and on other hand, whether these (possible) modifications of cell sensitivity involve autophagy and this by inducing or inhibiting autophagy by known pharmacological agents. Protein ubiquitination will be analyzed by immunofluorescence and western blot using antibodies against mono-and/or poly-ubiquitinated proteins.
4) Partnership, skills
Two partners with complementary skills are involved in this project:
– XLlM will provide us and control the RFR exposure system. This partner is experienced in dosimetry and in the control of temperature variations during exposure.
– EA3842: This partner will perform biological assays including cell cultures and the morphological and biological characterization of autophagy and cell death.