Anti-CASP3 monoclonal antibody, clone 4DTQ04

Oxidative stress increases with age in multiple organ systems and is implicated in the development of age-related pathologies in them. Studies from our laboratory show that the intrinsic pathway proapoptotic proteins BAX and caspase-3 (CASP3) lie upstream of mitochondrial production of oxidative stress-inducing reactive species (RS) such as reactive oxygen and reactive nitrogen species (ROS and RNS) in apoptotic and nonapoptotic neurons in cell culture. Our objective in this study was to determine if these findings could be generalized to the development of oxidative stress in nonneuronal tissues in vivo. We first investigated the effect of genetic deletion of Bax on DNA damage in the liver, heart and kidneys of female mice of increasing ages (5, 14, 22 months). The organs of the aged mice showed increased oxidative DNA strand breaks compared to young animals (5 month). Ablation of Bax greatly reduced this damage. We next assessed lipid peroxidation, DNA oxidation, and protein tyrosine nitration to determine whether Casp3 deletion reduces oxidative stress in the hearts, livers, and kidneys of 12-month-old female mice. Lipid peroxides and 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels were much lower in organs from mice with depleted Casp3 than in those of wild type animals. Nitration of protein tyrosine residues, caused by RNS, was also significantly suppressed in the tissues of Casp3 null mice compared to those in wild type mice. Our findings indicate that BAX and CASP3 have a vital role in the generation of oxidative stress in organs of aged mice.

Aims: To determine whether use of radiofrequency catheter ablation (RFCA) combined with intravenously administered liposomal doxorubicin (L-DOX) facilitates a reduction in the recovery of post-ablation electrical conduction. Methods: Circumferential ablation was performed on the epicardial surface of the left atrial appendage (LAA) in New Zealand White rabbits, and L-DOX was then administered intravenously. Fluorescence spectrophotometry was used to assess reagent bio-distribution, while Western blots and immunohistochemistry were used to assess the localization of the apoptotic markers Bcl-2, Bax, and cleaved CASP3 in the LAA. Liver, kidney, and cardiac functions were also measured to evaluate the safety of this approach. Results: At 1 week and 1 month after RFCA, a pacing electrocardiogram could not be detected in most of the rabbits that had received the combined RFCA and L-DOX therapy. L-DOX began to target the LAA on the second day after RFCA. L-DOX treatment increased the apoptosis of cardiomyocytes in the regions peripheral to the necrotic area induced by RFCA. Doxorubicin had some effect on liver and kidney function, but these effects were reversible and did not affect survival. Conclusion: The present results provide evidence that L-DOX treatment can reduce the recovery of electrical conduction after RFCA therapy owing to L-DOX-induced apoptosis of cardiomyocytes in the ablated area and the proximal transition zone of the LAA.