Analysis of anti-inflammatory effects of carvacrol and curcumin in vitro using the IPEC-J2 cell culture model

During weaning, piglets are exposed to a number of different stress factors accompanied by disproportionate inflammatory processes in the intestine, which can lead to an impairment of the intestinal barrier integrity and development of gastrointestinal disorders such as diarrhea. The pro-inflammatory transcription factor NFκB is considered as one of the key players in the development of inflammation and the control of NFκB is critical to overcome weaning-associated disturbance of animal health and reduced growth performance [1].

Formerly used antibiotic growth promoters have been banned in the EU since 2006 and there is a great demand for alternatives like plant-derived feed additives. This study evaluated the anti-inflammatory characteristics of the phytogenic feed additives carvacrol [50 µg/ml] and curcumin [1 µg/ml] in an intestinal porcine epithelial cell line (IPEC-J2) via the luminescence based NFκB reporter gene assay.

Cells were seeded in white 96-well plates and incubated at 39 °C and 5% CO₂. After 24 hours, cells reached approximately 70% confluence and were transfected with the NFκB reporter vector. Following 24 hours incubation time, cells were either pre-incubated with non-toxic test sample concentrations or just cultivation medium (DMEM/Ham's F12) in case of the cell control for another 24 hours. On the next day, the pro-inflammatory transcription factor NFκB was activated by stimulation with TNF-α for 5 hours and luminescence values were measured, which are directly proportional to the amount of activated NFκB.

After TNF-α stimulation, carvacrol and curcumin were both able to inhibit the activation of NFκB by 21% and 25% respectively, compared to TNF-α stimulated control cells. These results suggest promising inflammation restricting properties of carvacrol and curcumin in IPEC-J2. Further confirmation of the anti-inflammatory activities of both phytogenic compounds on mRNA and protein level is in progress.

[1] Gessner DK, et al. Acta Vet Scand 2013; 55: 18