In vitro investigation of individual and combined cytotoxic effects of aflatoxin B1 and other selected mycotoxins on the cell line porcine kidney 15

In the present study, we evaluated the nephrotoxicity of individual mycotoxins and combinations of aflatoxin B1 (AFB1), zearalenone (ZEA), deoxynivalenol (DON), and fumonisin B1 (FB1) to livestock using porcine kidney 15 cells (PK-15) as a disease model via biochemical approaches. The toxicity of individual mycotoxins on cell viability and cell membrane damage was determined using the MTT and lactate dehydrogenase (LDH) assays, respectively. Individual cytotoxicity of mycotoxins in increasing order were FB1 < ZEA < AFB1 < DON. The MTT results of central composite design (CCD) showed synergetic effects after co-exposure of AFB1 + ZEA or AFB1 + DON; however, AFB1 and ZEA showed antagonistic effects in the ternary mixtures. AFB1 and DON significantly induced ROS production and apoptosis in a concentration-dependent manner, but ZEA (10-40 μM) had no effect on cell apoptosis and only slightly induced ROS production. ZEA ameliorated the ROS production caused by 1 μM AFB1; however, ZEA and DON displayed synergistic effects in combination with AFB1 at 5 and 10 μM. The existence of 10 μM ZEA attenuated AFB1-induced apoptosis. In conclusion, AFB1 + ZEA or DON showed synergetic effects on cytotoxicity. Low levels of AFB1 were antagonistic to ZEA, but high doses of AFB1 displayed synergistic effects with ZEA or DON on oxidative damage. ZEA also ameliorated AFB1-induced apoptosis. Generally, the combined effects of mycotoxins acted in a concentration-dependent manner.