Vol.:(0123456789) 1 3
Neurochem Res
DOI 10.1007/s11064-017-2403-9
ORIGINAL PAPER
Diferential Molecular Targets for Neuroprotective Efect
of Chlorogenic Acid and its Related Compounds Against
Glutamate Induced Excitotoxicity and Oxidative Stress in Rat
Cortical Neurons
Olfa Rebai
1
· Manel Belkhir
1
· María Victoria Sanchez‑Gomez
3
· Carlos Matute
3
·
Sami Fattouch
2
· Mohamed Amri
1
Received: 21 June 2017 / Revised: 19 August 2017 / Accepted: 11 September 2017
© Springer Science+Business Media, LLC 2017
protective mechanism. Interseling, CGA and CA also exhibit
antiapoptotic properties against glutamate-induced cleaved
activation of pro-caspases; caspase 1,8 and 9 and calpain
(PD 150606,Calpeptin and MDL 28170).These data sug-
gest that neuroprotective activity of CGA ester may occurs
throught its hydrolysate,the cafeic acid and its interaction
with intracellular molecules suggesting that CGA exert its
neuroprotection via its cafeoly acid group that might poten-
tially be used as a therapeutic agent in neurodegeneratives
disorders associated with glutamate excitotoxicity.
Keywords Glutamate · Neuroprotection · Chlorogenic
acid · Antioxidant · Apoptosis · Molecular mechanisms
Abbreviations
CNS Central nervous system
DCF Dichlorofuorescein
FDA Fluorescein diacetate
H
2
O
2
Hydrogen peroxide
LDH Lactate dehydrogenase
PKA Protein kinase A
PKC Protein kinase C
PLC Phospholipase C
ROS Reactive oxygen species
MAPK Mitogen apoptotic protein kinase
DPPH 2, 2-diphenyl-1-picrylhydrazyl
DCF 2’, 7’-dichlorofuorescein
CGA Chlorogenic acid
CA Cafeic
QA Quinic acid
PBS Phosphate-bufered saline
LDH Lactate deshydrogenase
CAT Catalase
SOD Superoxide dismutase
NMDA N-methyl-D-aspartate
Abstract The present study has been designed to explore
the molecular mechanism and signaling pathway targets
of chlorogenic acid (CGA) and its main hydrolysates, caf-
feic (CA) and quinic acid in the protective efect against
glutamate-excitotoxicity. For this purpose 8-DIV cortical
neurons in primary culture were exposed to 50 μM L-glu-
tamic acid plus 10 µM glycine, with or without 10–100 μM
tested compounds. Chlorogenic acid and cafeic acid via
their antioxidant properties inhibited cell death induced by
glutamate in dose depended manner. However, quinic acid
slightly protects neurons at a higher dose. DCF, JC-1 and
Ca
2+
sensitive fuorescent dye fura-2, were used to measure
intracellular ROS accumulation, mitochondrial membrane
potential integration and intracellular calcium concentra-
tion [Ca
2+
]
i
. Results indicate that similarly, CGA acts as
a protective agent against glutamate-induced cortical neu-
rons injury by suppressing the accumulation of endogenous
ROS and restore the mitochondrial membrane potential,
activate the enzymatic antioxidant system by the increase
levels of SOD activity and modulate the rise of intracel-
lular calcium levels by increasing the rise of intracellular
concentrations of Ca
2+
caused by glutamate overstimula-
tion. PKC signaling cascade appear to be engaged in this
* Olfa Rebai
olfa.rebai@yahoo.fr
1
Research Unit of Functional Neurophysiology
and Pathology, 00/UR/08-01, Department of Biological
Sciences, Faculty of Science of Tunis, University of Tunis El
Manar, 2092 Tunis, Tunisia
2
Laboratoire de Biochimie Alimentaire, INSAT, University
of Carthage, Tunis, Tunisia
3
Departamento de Neurociencias, Facultad de Medicina y
Odontologia, Universidad Del Paıs Vasco, Leioa, Vizcaya,
Spain