Sicilian pistachio (Pistacia vera L.) nut inhibits expression and release of inflammatory mediators and reverts the increase of paracellular permeability in IL-1β-exposed human intestinal epithelial cells.

Gentile C, Perrone A, Attanzio A, Tesoriere L, Livrea MA.

Eur J Nutr. 2015;54(5):811-821.

Dietary approaches to control inflammatory bowel diseases (IBD) may include proanthocyanidin-rich foods. Previous research showed that a hydrophilic extract from Sicilian pistachio nut (HPE) contains substantial amounts of proanthocyanidins and possesses anti-inflammatory activities.

HPE was prepared by Pistacia vera L. nuts, and PPF was isolated from HPE by adsorbance chromatography. Proanthocyanidins were quantified as anthocyanidins after acidic hydrolysis. Differentiated Caco-2 cells were pre-incubated with HPE or PPF and then were exposed to IL-1β. Cell viability and parameters associated with nuclear factor-κB (NF-κB) activation were assayed. Adsorption of polymeric proanthocyanidins to the cell membrane was investigated by transepithelial electrical resistance (TEER) measurements.

Results provide evidence that pistachio nut components inhibit inflammatory response of intestinal epithelial cells in vitro and indicate polymeric proanthocyanidins as the major bioactive nut components. The protection implies inhibition of NF-κB activation and occurs in parallel with the adsorption of polymeric proanthocyanidins to cell membrane. These findings suggest that intake of small amounts of pistachio nut can exert beneficial effects to gastrointestinal pathophysiology.