PARP1 and diabetes mellitus: In view of the similarity of protective actions manifested by TAU, 3-AB and NIC against diabetes it appeared of interest to determine whether or not TAU is endowed with PARP-inhibiting action and, if this is the case, to what extent differences in PARP-inhibiting potency among TAU, 3-AB and NIC impact on the extent of their antidiabetic effects.