Premium Only Content

Prof. Christian Andre Amatore @ FLOGEN SIPS 2022 Yoshikawa Intl. Symposium on Oxidative Stress #2
FLOGEN SIPS 2022: Yoshikawa International Symposium on Oxidative Stress for Sustainable Development of Human Beings (2nd international Symposium)
Presenter:
Prof. Christian Andre Amatore, CNRS & PSL, French Academy of Sciences, Paris, France
Title:
Nanometer-sized electrochemical probes for intracellular measuring ROS/RNS in single cells and cellular organelles
Abstract
Oxidative stress conditions are encountered by all aerobic organisms during their whole life. Indeed, aerobic cells mostly derive their energy from the intracellular enzyme-catalyzed oxidation of fat and sugars to CO2. Also, metalloenzymes which are central actors of the respiratory chain in mitochondria are generally good reducing agents, prone to open side routes leading to O2 reduction to superoxide ion (O2•-) that is the precursor of a series of hazardous species collectively named as “reactive oxygen species (ROS)” and “reactive nitrogen species (RNS)” [1,2]. ROS and RNS may induce molecular damages to almost all organic compounds performing biological functions (nucleic acids, proteins, cells carbohydrates and lipids, etc.) – a situation termed “oxidative stress” when it runs out of control. Even without exposure to radiation or other photo-biological effects, oxidative stress can bring about such pathological conditions as inflammation, carcinogenesis, Parkinson and Alzheimer diseases, and various autoimmune illnesses, as well as accelerated ageing. The primary ROS/RNS, viz., hydrogen peroxide, peroxynitrite ion, nitric oxide, and nitrite ion, can be oxidized at different electrode potentials and therefore detected and quantified by electroanalytical techniques [3]. Nanometer-sized electrochemical probes with cylindrical shapes do not experience this problem since they can penetrate across the cell membranes that reseal around their shaft (7). They are then especially suitable for measuring ROS/RNS in single cells and cellular organelles. In this paper, we will survey recent advances in localized measurements of ROS/RNS inside single cells. Application of this method will be presented for detection of ROS/RNS in phagolysosomes during phagocytosis by macrophages (4,5). We will also evidence using these methods that remediation of Oxidative Stress in neurons artificially placed under Parkinson Disease conditions avoids the impeachment of synaptic communication when the neurons are pre-treated with Harpagide, a natural sugar derivative which alleviate the oxide stress borne by mitochondria (9).
References:
(1) B. Halliwell, J.M.C. Gutteridge, Free Radicals in Biology and Medicine, 3rd ed., Oxford University Press, Oxford, 1999.
(2) F. Murad: Discovery of Some of the Biological Effects of Nitric Oxide and its Role in Cell Signaling. Nobel Lecture for Medicine, 1998, https://www.nobelprize.org/uploads/20...
(3) C Amatore, S. Arbault, M. Guille, F. Lemaître: Electrochemical monitoring of single cell secretion: vesicular exocytosis and oxidative stress. Chem. Rev. 108 (2008) 2585–2621.
(4) K. Hu, Y.L. Liu, A. Oleinick, M.V. Mirkin, W.H. Huang, C. Amatore: Nanoelectrodes for Intracellular Measurements of Reactive Oxygen and Nitrogen Species in Single Living Cells. Curr. Opin. Electrochem., 22, 2020, 44-50, and refs therein.
(5) Y.T. Qi, H. Jiang, W.T. Wu, F.L. Zhang, S.Y. Tian, W.T. Fan, Y.L. Liu, C. Amatore, W.H. Huang: Homeostasis Inside Single Activated Phagolysosomes: Quantitative and Selective Measurements of sub-Millisecond Dynamics of ROS/RNS Production with a Nanoelectrochemical Sensor. J. Am. Chem. Soc., 144, 2022, 9723-9733.
-
LIVE
Russell Brand
2 hours agoUK Migration Clashes ERUPT! Starmer Sweats as ‘SUMMER OF RIOTS’ Begins? - SF620
18,419 watching -
LIVE
Sean Unpaved
1 hour agoBat Flips to Boardrooms: Jets QB Crossroads, Presidential Visits, & RedZone's TV Takeover
327 watching -
LIVE
RalliedLIVE
17 minutes agoSPECIALIST ADDICTED MAN WINS WARZONE SOLOS
65 watching -
LIVE
Donut Operator
2 hours agoI'M BACK/ CRIME/ GAMEBOY CAMERA CHAD
371 watching -
1:06:18
Timcast
1 hour agoDOJ Launches STRIKE FORCE To Investigate Obama Over TREASON Claims
43.8K38 -
2:09:08
Steven Crowder
4 hours ago🔴Is Trump Confirmed To Be on the Epstein List - What the Hell Is Going On?
235K202 -
LIVE
The Charlie Kirk Show
1 hour agoLet's Talk Legal Immigration + Tulsi on ObamaGate + Hillary's Bribes | Gabbard, Rep. Steube, Basham
5,320 watching -
LIVE
Rebel News
31 minutes agoConvoy sentencing continues, Asylum seeker work permits, Premiers back ostrich farm | Rebel Roundup
330 watching -
LIVE
TheAlecLaceShow
1 hour agoGuest: Rep. Troy Nehls | Tulsi & Karoline Presser | Russiagate | Epstein | The Alec Lace Show
39 watching -
LIVE
Flyover Conservatives
12 hours agoTracing the Nephilim from Noah to the US Dollar - Dr. Laura Sanger | FOC Show
1,847 watching