Oak and chestnut wood extracts enhance the intestinal gut barrier function in a porcine in vitro cell model

The protective effect of oak wood and chestnut wood extracts on the gut barrier function of a porcine intestinal epithelial cell line (IPEC-J2) was investigated. Tannins, polyphenolic compounds, are likely to improve the impaired epithelial barrier function by inhibiting the disruptive effect of TNF-α [Ren et al., 2012]. Therefore, extracts from oak and chestnut wood were prepared and tested in an in vitro cell culture model, using non-transformed, differentiated IPEC-J2. Cells were seeded in non-coated Transwell® membrane inserts (1.12 cm²; 0.4 µm pore size) for 7 days, allowing the formation of tight junctions (TJs) and the build-up of a representative intestinal layer, which was observed by an increase of transepithelial electrical resistance (TEER). Cells were pre-treated with a previously selected non-toxic concentration of the respective extracts. On day 8, a stressor was additionally added to the pre-treated cells and to the control. TEER was measured after 24, 48, and 72h. Following the final TEER measurement, a neutral red cytotoxicity assay was performed.

Oak wood extract (1,000 µg/mL) alone already increased the TEER value by 11.0 – 15.0% at each time point, compared to the control. Together with the stressor, the substance enhanced TEER values by 34% (24h), 32% (48h), and 21% (72h), compared to the stressor control. Additionally, chestnut wood extract [250 µg/ml] showed potent effects, by increasing TEER by 10.0 – 14.5%, depending on the measured time point. Furthermore, the extract had a protective effect against the stressor-induced impairment of intestinal barrier function, by increasing TEER by 34% (24h), 35% (48h), and 24% (72h).

Positive modulation of gut barrier parameters have been shown by both phytogenic extracts.

Acknowledgements: Funding by the Austrian Research Promotion Agency (FFG) is gratefully acknowledged.

Keywords: gut health, transepithelial electrical resistance (TEER), cell culture.

References:

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