Table 1.

Rheumatoid arthritis-inhibiting phenolic acid, stilbenes, flavonoids, and other polyphenols.

Polyphenols	Source	Experimental Setup	Actioning Mechanism	Ref.
Ferulic acid	apple, sugar beet, popcorn, grains, vegetables	Macrophage, monocytes, Rats	NFATc1, c-Fos, NF-κB, MMP	[32]
N-feruloyl serotonin	safflower seed	AA	CRP, LOX, TNF-α, iNOS, IL-1β	[33]
Resveratrol	red grapes, peanut, soy	CIA, FLS	COX-2, PGE2, NADPH oxidase, ROS, p38, MAPK, ERK1/2, NF-κB	[39]
Epigallocatechin-3-gallate	green tea, strawberries, blackberries	CIA rat	IL-6, TNF-α, IFN-γ	[129,130]
Gallic acid	cinnamon bark	AIA rat	TNF-α	[32,33,147]
EVOO polyphenol extract	EVOO, fruit of olea, olives	CIA	TNF-α, IL-1β, IL-6, PEG2, p38, JNK, p65	[55]
Curcumin	turmeric rhizome	RA-FLS	IL-1β, IL-6, NF-κB, ERK1/2	[70]
p-Coumaric acid	gnetum	AIA	TNF-α, IgG	[34]
Emodin	rhubarb, asian knotweed	Synovial membrane in human	MMP-1, MMP-9, NF-κB, MAPK	[57]
Hesperidin	soybean, sweet orange, tangerine	Wistar rat	GSH, SOD, catalase	[47,48]

AA: amyloidosis; AIA: adjuvant-induced arthritis; NFATc1: nuclear factor of activated T cells cytoplasmic-1, NF-κB: nuclear factor kappa light chain enhancer of activated B cells, MMP: matrix metalloproteinases, COX-2: cyclooxygenase, PGE2: prostaglandins E2, NADPH: nicotinamide adenine dinucleotide phosphates, ROS: reactive oxygen species, MAPK: mitogen-activated protein kinase, ERK1/2: extracellular signal-directed kinase, IL: interleukin, TNF: tumor necrosis factor, IFN-γ: interferon gamma, PEG2: polyethylene glycol-2, p38: phospho-p38 mitogen-activated protein kinase JNK: Jun N-terminal kinases, p65: phospho-p65 mitogen-activated protein kinase, IgG: immunoglobulin G, EVOO: extra virgin olive oil, CIA: collagen-induced arthritis, AIA: rat adjuvant arthritis, RA-FLS: rheumatoid arthritis-fibroblast-like synoviocyte; GSH: glutathione; SOD: superoxide dismutase.