Table 1.

In vitro studies on olive oil polyphenols and intestinal inflammation.

Study	Cell Type	Intervention	Results
Chiesi et al. [42]	Caco-2 cells stimulated with alternariol	EVOO extract, Oleuropein, Tyrosol	↓ ROS ↓ cytotoxicity
Muto et al. [43]	Caco-2 cells stimulated with LPS or IL-1β	EVOO phenolic extract	↓ IL-8 expression and secretion
Serelli et al. [44]	Caco-2 cells treated with LPS	HT and Tyr metabolites	↓ degradation of IĸBα ↓ iNOS expression
Di Nunzio et al. [45]	Caco-2 cells treated with IL-1β	Polyphenols sourced from olive pomace	↓ IL-8
Incani et al. [46]	Caco-2 cells treated with tert-butyl hydroperoxide (TBH) or a mixture of oxysterols	Preincubation with the phenolic extracts	↓ ROS
Borges et al. [47]	Caco-2 cell cultures	Six Spanish monovarietal EVOOs (EVOOs’ bioaccessible fractions (BF) after in vitro digestion	↑ phenolic count and anti-oxidant activity ↓ ROS
Gill et al. [48]	In vitro model of colon carcinogenesis (HT-29 cells treated with hydrogen peroxide, Caco-2 cells, HT115 cells)	EVOO phenols	anti-genotoxic effect ↑ barrier function in Caco-2 cells ↓ HT115 cell invasion and attachment
Larrussa et al. [51]	Ex vivo organ culture of mucosal explants from UC patients	Oleuropein	↓ COX 2 and IL-17 expression ↓ infiltration of CD3, CD 4 and CD20 cells ↑ mucosal healing
Vezza et al. [52]	Ex vivo colon cultures from CD patients, DSS and DNBS mice colitis models	Olive leaf extract	↓ expression of IL-1β, TNF-α, and iNOS ↑ epithelial barrier (ZO-1, MUC-2, and TFF-3)

Abbreviations: EVOO: extra-virgin olive oil, ROS: reactive oxygen species, IĸBα: inhibitor of ĸappa Bα, iNOS: inducible nitric-oxide synthetase, IL-8: interleukin 8, IL-17: interleukin 17, TNF-α: tumour necrosis factor alpha, COX 2: cyclooxygenase 2, ZO-1: zonula occludes protein 1, MUC-2: mucin 2, TFF-3: intestinal trefoil factor, ↓ = decrease in, ↑ = increase in.