MAPT and Alzheimer disease: Alonso et al. examined the effect of Gambierol (170), a polycyclic ether toxin produced by a dinoflagellate Gambierdiscus toxicus, and its synthetic heptacyclic (171) and tetracyclic (172) analogues (Figure 13) in an in vitro model of AD, obtained from triple transgenic (3xTg-AD) mice that express Aβ accumulation and tau hyperphosphorylation.