Protective effects of distinct proline-rich oligopeptides from B. jararaca snake venom against oxidative stress-induced neurotoxicity

Abstract The low molecular mass fraction from Bothrops jararaca snake venom contains proline-rich peptides ( Bj -PROs), also known as bradykinin-potentiating peptides (BPPs), which were described as neuroprotective against H 2 O 2 -induced oxidative stress. Recently, we reported that the neuroprotective action of Bj-PRO-10c ( Bj -PRO-5a ( Bj -PRO-7a ( Bj -PRO-11e ( Bj -PRO-AP ( 2 O 2 -induced oxidative stress in SH-SY5Y cells. Bj-PROs tested were neuroprotective, but Bj-PRO-5a and Bj-PRO-7a increased cell viability by more than 85% in the presence of H 2 O 2 (450 μM) and reduced the oxidative stress markers. AsS, iNOS, and NF-ĸB expressions were not involved in the neuroprotective mechanism for both peptides, in contrast to Bj -PRO-10c, as reported in the literature. Bj -PRO-5a is a neuroprotector peptide that decreases ROS production, NO levels lipid peroxidation, and changes in mitochondrial membrane permeability caused by H 2 O 2 exposition. The neuroprotective property of Bj -PRO-7a against H 2 O 2 is also related to decreased ROS production and lipid peroxidation but without altering NO levels. These results show that the protective effects of different Bj -PROs against oxidative stress can be explained by distinct mechanisms independent of an increase in L-arginine bioavailability arising from AsS activity. Further studies are now needed to reveal the details of the neuroprotective mechanisms exerted by Bj -PROs.