Alternariol (AOH) is a toxic metabolite produced by Alternaria alternata and A. tenuissima, which grow on corn, rice, fruits, vegetables and oilseed. Mycotoxins are biologically active secondary fungal metabolites found as contaminants of food- and feedstuff [1].

Alternariol (0.8 μM) inhibited P4 secretion. Alternariol (1.6 μM) significantly reduced cell viability [1]. Alternariol (0.8 μM) reduced the expression of P450scc protein. Alternariol (1.6 μM) significantly reduced the abundance of α-tubulin and also clearly affected actin protein concentrations. Alternariol specifically inhibited P4 secretion in cultured porcine granulosa cells [1]. Twelve hours of light exposure was sufficient to decrease significantly the production of alternariol [2]. Light inhibited the production of alternariol in Alternaria alternate [2]. Alternariol was preferentially metabolized by cytochrome P450 (CYP) 1A1 and 1A2. Alternariol enhanced the levels of CYP1A1 in murine hepatoma cells (Hepa-1c1c7) but not in cells with inactivated AhR (Hepa-1c1c12) or ARNT (Hepa-1c1c4). Alternariol showed no effects on the production of reactive oxygen species but reduced cell counts in Hepa-1c1c7 cells after 24 and 48 h. At 48 h, AOH increased apoptosis dependent on AhR and ARNT [3].

References:
[1] Tiemann U, Tomek W, Schneider F, et al. The mycotoxins alternariol and alternariol methyl ether negatively affect progesterone synthesis in porcine granulosa cells in vitro[J]. Toxicology Letters, 2009, 186(2): 139-145.
[2] Sderhll K, Svensson E, Unestam T. Light inhibits the production of alternariol and alternariol monomethyl ether in Alternaria alternata[J]. Applied and environmental microbiology, 1978, 36(5): 655-657.
[3] Schreck I, Deigendesch U, Burkhardt B, et al. The Alternaria mycotoxins alternariol and alternariol methyl ether induce cytochrome P450 1A1 and apoptosis in murine hepatoma cells dependent on the aryl hydrocarbon receptor[J]. Archives of toxicology, 2012, 86(4): 625-632.