AD	Alzheimer’s disease
ALT	Alanine aminotransferase
AST	Aspartate amino transferase
AAE	Ascorbic acid equivalents
BHT	Butylated hydroxytoluene
BP	Blood pressure
CAT	Catalase
CE	(+)-Catechin equivalents
CFU	Colony-forming unit
CNS	Central nervous system
DPPH	2,2-diphenyl-1-picrylhydrazyl
EA	Ethyl acetate fraction
EC50	Half maximal effective concentration
EC	Epicatechin
ECE	(+)-Epicatechin equivalents
ECG	Epicatechin gallate
EFB	Empty fruit bunches
EGC	Epigallocatechin
EGCG	Epigallocatechin gallate
FAE	Ferulic acid equivalents
FRAP	Ferric reducing/antioxidant power
FTIR	Fourier transform infrared spectroscopy
GAE	Gallic acid equivalents
GGT	Gamma-glutamyl transferase
GPx	Glutathione peroxidase activity
HDL	High density lipoprotein
HDL-C	High-density lipoprotein cholesterol
HEX	Hexane fraction
1H-NMR	Proton nuclear magnetic resonance
HPLC	High-performance liquid chromatography
HPSA	Hydrogen peroxide scavenging activity
IC50	Half-maximal inhibitory concentration
INSOL	Insoluble fraction
LA	Linoleic acid
LC-MS	Liquid chromatography–mass spectrometry
LD50	Median lethal dose
LDL	Low-density lipoprotein
LDLr	Low-density lipoprotein receptor
L-NAME	Nω-nitro-L-arginine methyl ester
LPO	Lipid peroxidation
MTT	3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyl tetrazolium bromide
MDA	Malonyldialdehyde
MeOH	Methanolic extract
MF	Mesocarp fibre
MIC	Minimum inhibitory concentration
MMPs	Matrix metalloproteinases
NO	Nitric oxide
NOLA	Nω-nitro-L-arginine
NOS	Nitric oxide synthase
NOS	Nitric oxide scavenging
N/R	Not reported
OPB	Oil palm biomass
OPAL	Oil palm leaves alcoholic extract
OPL	Oil palm leaves
OPLE	Oil palm leaf extract
OPT	Oil palm trunk
OVX	Ovariectomized
PKS	Palm kernel shell
POME	Palm oil mill effluent
PRISMA	Preferred Reporting Items for Systematic reviews and Meta-Analyses
PUFA	Polyunsaturated fatty acid
QCE	Quercetin equivalents
ROS	Reactive oxygen species
SOD	Superoxide dismutase
SAR	Structure activity relationship
STZ	Streptozotocin
TCK	Creatine kinase
TBARS	Conjugated diene formation and thiobarbituric acid reactive substance
TPC	Total phenolic content
TPTZ	Tripyridyltriazine
UHPLC-UV/PDA	Ultrahigh performance liquid chromatography-ultraviolet/photodiode array
TFC	Total flavonoid content
TBARS	Conjugated diene formation and thiobarbituric acid reactive substance