Daniela Calzia1, Michele Oneto1, Federico Caicci2, Paolo Bianchini3, Silvia Ravera1, Martina Bartolucci1, Alberto Diaspro3, Paolo Degan4, Lucia Manni2, Carlo Enrico Traverso5, Isabella Panfoli1. 1. Department of Pharmacy-DIFAR, Biochemistry and Physiology Laboratory, University of Genoa, Genova, Italy. 2. Department of Biology, Università di Padova, Padova, Italy. 3. Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy. 4. UOC Mutagenesi, IRCCS Azienda Ospedaliera Universitaria San Martino - Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy. 5. Clinica Oculistica, Di.N.O.G.M.I., University of Genoa, IRCCS Azienda Ospedaliera Universitaria San Martino - Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy.
Abstract
BACKGROUND AND PURPOSE: The rod outer segments (OS) of the retina are specialized organelles where phototransduction takes place. The mitochondrial electron transport complexes I-IV, cytochrome c and Fo F1 -ATP synthase are functionally expressed in the OS disks. Here, we have studied the effect of some polyphenolic compounds acting as inhibitors of mitochondrial ATPase/synthase activity on the OS ectopic Fo F1 - ATP synthase. The mechanism of apoptosis in the OS was also investigated studying the expression of cytochrome c, caspase 9 and 3 and Apaf-1. EXPERIMENTAL APPROACH: We prepared OS from fresh bovine retinae. Semi-quantitative Western blotting, confocal and electron microscopy, and cytofluorimetry were used along with biochemical analyses such as oximetry, ATP synthesis and hydrolysis. KEY RESULTS: Resveratrol and curcumin plus piperine inhibited ATP synthesis and oxygen consumption in the OS. Epigallocatechin gallate and quercetin inhibited ATP hydrolysis and oxygen consumption in the OS. Malondialdehyde and hydrogen peroxide were produced in respiring OS in the presence of substrates. Cytochrome c was located inside the disk membranes. Procaspase 9 and 3, as well as Apaf-1 were expressed in the OS. CONCLUSIONS AND IMPLICATIONS: These polyphenolic phytochemicals modulated the Fo F1 -ATP synthase activity of the the OS reducing production of reactive oxygen intermediates by the OS ectopic electron transport chain. Polyphenols decrease membrane peroxidation and cytochrome c release from disks, preventing the induction of caspase-dependent apoptosis in the OS Such effects are relevant in the design of protection against functional impairment of the OS following oxidative stress from exposure to intense illumination.
BACKGROUND AND PURPOSE: The rod outer segments (OS) of the retina are specialized organelles where phototransduction takes place. The mitochondrial electron transport complexes I-IV, cytochrome c and Fo F1 -ATP synthase are functionally expressed in the OS disks. Here, we have studied the effect of some polyphenolic compounds acting as inhibitors of mitochondrial ATPase/synthase activity on the OS ectopic Fo F1 - ATP synthase. The mechanism of apoptosis in the OS was also investigated studying the expression of cytochrome c, caspase 9 and 3 and Apaf-1. EXPERIMENTAL APPROACH: We prepared OS from fresh bovine retinae. Semi-quantitative Western blotting, confocal and electron microscopy, and cytofluorimetry were used along with biochemical analyses such as oximetry, ATP synthesis and hydrolysis. KEY RESULTS:Resveratrol and curcumin plus piperine inhibited ATP synthesis and oxygen consumption in the OS. Epigallocatechin gallate and quercetin inhibited ATP hydrolysis and oxygen consumption in the OS. Malondialdehyde and hydrogen peroxide were produced in respiring OS in the presence of substrates. Cytochrome c was located inside the disk membranes. Procaspase 9 and 3, as well as Apaf-1 were expressed in the OS. CONCLUSIONS AND IMPLICATIONS: These polyphenolic phytochemicals modulated the Fo F1 -ATP synthase activity of the the OS reducing production of reactiveoxygen intermediates by the OS ectopic electron transport chain. Polyphenols decrease membrane peroxidation and cytochrome c release from disks, preventing the induction of caspase-dependent apoptosis in the OS Such effects are relevant in the design of protection against functional impairment of the OS following oxidative stress from exposure to intense illumination.
Authors: Stephen P H Alexander; Helen E Benson; Elena Faccenda; Adam J Pawson; Joanna L Sharman; Michael Spedding; John A Peters; Anthony J Harmar Journal: Br J Pharmacol Date: 2013-12 Impact factor: 8.739
Authors: Nora Heinig; Ulrike Schumann; Daniela Calzia; Isabella Panfoli; Marius Ader; Mirko H H Schmidt; Richard H W Funk; Cora Roehlecke Journal: Int J Mol Sci Date: 2020-03-30 Impact factor: 5.923
Authors: Angela Bisio; Anna M Schito; Francesca Pedrelli; Ombeline Danton; Jakob K Reinhardt; Giulio Poli; Tiziano Tuccinardi; Thomas Bürgi; Francesco De Riccardis; Mauro Giacomini; Daniela Calzia; Isabella Panfoli; Gian Carlo Schito; Matthias Hamburger; Nunziatina De Tommasi Journal: J Nat Prod Date: 2020-03-17 Impact factor: 4.050