Pleiotropic Effects of Eugenol: The Good, the Bad, and the Unknown

Table 2

Overview of the anti-inflammatory, antioxidant, and anticarcinogenic effects of eugenol.

Eugenol properties	Parameters/tumor type	Biological effects	Ref.
Anti-inflammatory	Histological quantification of liver inflammatory foci/microscopic field	Decrease of the liver inflammatory cell infiltration	[90]
Anti-inflammatory	Cytokine levels	Decrease of the TNF-α and IL-6 level in the culture supernatant of RA-PBMCs	[91]
Anti-inflammatory	Mouse skin expression of COX-2 cytokine levels	Decrease of skin COX-2 expression and serum TNF-α, IL-6, and PGE2 level in TPA-treated mice	[95]
Anti-inflammatory	Leukocyte migration	Decrease of the number and adherence of leukocytes	[86]
Anti-inflammatory	Cytokine levels	Inhibition of lung infiltration with eosinophils decrease of IL-4 and IL-5 levels	[89]
Anti-inflammatory	Cytokine levels	Inhibition of TNF-α, IL-1β, and IL-6 release	[88]
Anti-inflammatory	Inflammatory cells cytokine level NF-κB activation	Inhibition of lung infiltration with neutrophils/macrophages; reduction of TNF-α release and of NF-κB activation	[76]
Anti-inflammatory	Inflammation-related gene expression (NF-κB, IL-1β, and TNF-α)	Inhibition of NF-κB and TNF-α gene expression	[61]
Antioxidant	Antioxidant enzyme (SOD and CAT) activity	Increase of serum SOD and CAT activity	[90]
Antioxidant	Intracellular ROS production and reduced glutathione level antioxidant enzyme (SOD, CAT, and GPx) activity	Decrease of ROS generation and increase of reduced glutathione level in RA-PBMC increase of SOD, CAT, and GPx activity in RA-PBMC culture	[91]
Antioxidant	Cutaneous glutathione level and glutathione reductase, CAT, and GPx activity	Increase of cutaneous glutathione level and glutathione reductase, CAT, and GPx activity in TPA-treated mice	[95]
Anticarcinogenic	MCF-7 human breast cancer cells	Inhibition of human breast cancer cell proliferation	[102]
Anticarcinogenic	Mouse skin cancer	Reduction in tumor size and incidence	[95]
Anticarcinogenic	Mouse skin cancer	Restriction of skin carcinogenesis at the dysplastic stage	[96]
Anticarcinogenic	Rat gastric cancer	Inhibition of gastric carcinoma development through NF-κB suppression	[99]
		Apoptosis stimulation through modulation of Bcl-2 proteins, Apaf-1, caspases, and cytochrome c inhibition of invasion and angiogenesis by MMP activity and VEGF and TIMP-2 expression modulation	[98]
Anticarcinogenic	HSC-2 human oral squamous cell carcinoma cell line	Nonapoptotic cell death through oxidative stress and reduction of ATP utilization	[108]
Anticarcinogenic	Human melanoma cells B16 xenograft mouse model	Tumor size reduction and delay in tumor growth; prevention of metastasis	[97]
Anticarcinogenic	Human breast cancer cells	Proliferation inhibition and apoptosis stimulation through down-regulation of survivin and the E2F1 transcription factor	[103]
Anticarcinogenic	A549 human lung adenocarcinoma cells	Inhibition of cell proliferation, migration, and invasion through modulation of MMP activity and the PI3K/Akt pathway	[100]
Anticarcinogenic	HCT-15 and HT-29 human colorectal adenocarcinoma cells	Apoptosis stimulation through the reduction of ΔΨm with oxidative stress and DNA fragmentation	[106]
Anticarcinogenic	HL-60 human promyelocytic leukemia cells	Apoptosis stimulation through oxidative stress, MPT, and cytochrome c release, reduction of Bcl-2 level and DNA fragmentation	[107]
Anticarcinogenic	Human KB oral squamous carcinoma cells and DU-145 androgen-insensitive prostate cancer cells	Cell growth inhibition and apoptosis stimulation	[104]
Anticarcinogenic	MDA-MB-231, MCF-7 (breast cancer lines), SIHA (cervix cancer lines), SK-Mel-28, and A2058 (melanoma lines)	Apoptosis stimulation through cell cycle deregulation and DNA damage, ROS overproduction, disruption of the cytoplasmic membrane, mitochondrial failure, PCNA downregulation	[105]

RA-PBMCs: PBMCs isolated from rheumatoid arthritis patients; TPA: 12-O-tetradecanoylphorbol-13-acetate; MAPK: mitogen-activated protein kinases; SOD: superoxide dismutase; CAT: catalase; GPx: glutathione peroxidase; PARP: polyadenosinediphosphate-ribose polymerase; MPT: mitochondrial permeability transition; PCNA: proliferation cell nuclear antigen; ΔΨm: mitochondrial membrane potential.