Activation of the Pro-Oxidant PKCβII-p66Shc Signaling Pathway Contributes to Pericyte Dysfunction in Skeletal Muscles of Patients With Diabetes With Critical Limb Ischemia.
Critical limb ischemia (CLI), foot ulcers, former amputation, and impaired regeneration are independent risk factors for limb amputation in subjects with diabetes. The present work investigates whether and by which mechanism diabetes negatively impacts on functional properties of muscular pericytes (MPs), which are resident stem cells committed to reparative angiomyogenesis. We obtained muscle biopsy samples from patients with diabetes who were undergoing major limb amputation and control subjects. Diabetic muscles collected at the rim of normal tissue surrounding the plane of dissection showed myofiber degeneration, fat deposition, and reduction of MP vascular coverage. Diabetic MPs (D-MPs) display ultrastructural alterations, a differentiation bias toward adipogenesis at the detriment of myogenesis and an inhibitory activity on angiogenesis. Furthermore, they have an imbalanced redox state, with downregulation of the antioxidant enzymes superoxide dismutase 1 and catalase, and activation of the pro-oxidant protein kinase C isoform β-II (PKCβII)-dependent p66Shcsignaling pathway. A reactive oxygen species scavenger or, even more effectively, clinically approved PKCβII inhibitors restore D-MP angiomyogenic activity. Inhibition of the PKCβII-dependent p66Shcsignaling pathway could represent a novel therapeutic approach for the promotion of muscle repair in individuals with diabetes.
Istituto di Ricovero e Cura a Carattere Scientifico, MultiMedica, Milan, Italy.
Rosa
R
Vono
Department of Biology, University of Rome Tor Vergata, Rome, Italy.
Claudia
C
Fuoco
Department of Biology, University of Rome Tor Vergata, Rome, Italy.
Stefano
S
Testa
Department of Biology, University of Rome Tor Vergata, Rome, Italy.
Stefano
S
Pirrò
Istituto di Ricovero e Cura a Carattere Scientifico, MultiMedica, Milan, Italy.|Department of Biomedical Sciences, University of Sassari, Sassari, Italy.
Davide
D
Maselli
Bristol Heart Institute, University of Bristol, Bristol, U.K.
David
D
Ferland McCollough
Istituto di Ricovero e Cura a Carattere Scientifico, MultiMedica, Milan, Italy.
Elena
E
Sangalli
Department of Biomedical Sciences, University of Sassari, Sassari, Italy.|Department of Biomedical Sciences, College of Health Sciences, Qatar University, Doha, Qatar.
Gianfranco
G
Pintus
Department of Biomedical Sciences, University of Sassari, Sassari, Italy.
Roberta
R
Giordo
Department of Pathology, University of Insubria/Ospedale di Circolo, Varese, Italy.
Giovanna
G
Finzi
Department of Pathology, University of Insubria/Ospedale di Circolo, Varese, Italy.
Fausto
F
Sessa
Laboratory of Muscle Histopathology and Molecular Biology, Istituto di Ricovero e Cura a Carattere Scientifico-Policlinico San Donato, Milan, Italy.
Rosanna
R
Cardani
Istituto di Ricovero e Cura a Carattere Scientifico, MultiMedica, Milan, Italy.
Ambra
A
Gotti
Istituto di Ricovero e Cura a Carattere Scientifico, MultiMedica, Milan, Italy.
Sergio
S
Losa
Department of Biology, University of Rome Tor Vergata, Rome, Italy.
Gianni
G
Cesareni
Istituto di Ricovero e Cura a Carattere Scientifico, MultiMedica, Milan, Italy.|Cell Biology and Neurobiology Institute, National Research Council of Italy, Rome, Italy.
Roberto
R
Rizzi
Istituto di Ricovero e Cura a Carattere Scientifico, MultiMedica, Milan, Italy.|Cell Biology and Neurobiology Institute, National Research Council of Italy, Rome, Italy.
Claudia
C
Bearzi
Department of Biology, University of Rome Tor Vergata, Rome, Italy.
Stefano
S
Cannata
Istituto di Ricovero e Cura a Carattere Scientifico, MultiMedica, Milan, Italy paolo.madeddu@bristol.ac.uk cesare.gargioli@uniroma2.it gaia.spinetti@multimedica.it.
Gaia
G
Spinetti
Department of Biology, University of Rome Tor Vergata, Rome, Italy paolo.madeddu@bristol.ac.uk cesare.gargioli@uniroma2.it gaia.spinetti@multimedica.it.
Cesare
C
Gargioli
Department of Biomedical Sciences, University of Sassari, Sassari, Italy paolo.madeddu@bristol.ac.uk cesare.gargioli@uniroma2.it gaia.spinetti@multimedica.it.
Paolo
P
Madeddu
D000368:Aged; D015153:Blotting, Western; D049109:Cell Proliferation / Q000187:drug effects; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D007511:Ischemia / Q000378:metabolism*; D008297:Male; D046529:Microscopy, Electron, Transmission; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects; D020286:Pericytes / Q000187:drug effects / Q000378:metabolism*; D010797:Phthalimides / Q000494:pharmacology; D064546:Protein Kinase C beta / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects
D010797:Phthalimides; D017382:Reactive Oxygen Species; D064546:Protein Kinase C beta; C098874:4,5-dianilinophthalimide