Administration of Human Protein-C concentrate prevents apoptotic brain cell death after experimental sepsis

• Published in: Brain research 2009-04, Vol.1264, p.119-126
• Main Authors: Memos, Nikolaos, Betrosian, Alex, Messaris, Evangelos, Boutsikou, Maria, Kataki, Agapi, Chatzigianni, Emmy, Nikolopoulou, Marilena, Leandros, Emmanuel, Konstadoulakis, Manousos
• Format: Article
• Language: English
• Subjects: Ageing, cell death; Animals; Apoptosis; Apoptosis - drug effects; Astrocytes - drug effects; Astrocytes - metabolism; Astrocytes - pathology; bcl-2-Associated X Protein - metabolism; Biological and medical sciences; Brain; Brain - drug effects; Brain - metabolism; Brain - pathology; Caspases - metabolism; Cell physiology; Cytochromes c - metabolism; Cytoprotection; Flow Cytometry; Fundamental and applied biological sciences. Psychology; Immunohistochemistry; Male; Molecular and cellular biology; Neurology; Neurons - drug effects; Neurons - metabolism; Neurons - pathology; Protein C - pharmacology; Protein C zymogen; Proto-Oncogene Proteins c-bcl-2 - metabolism; Rats; Rats, Wistar; Sepsis; Sepsis - metabolism; Sepsis - pathology; Time Factors
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/j.brainres.2009.01.053

Abstract Activated Protein C renders anti-apoptotic properties in neurons and endothelial cells. The aim of the present study was to evaluate the in vivo cytoprotective role of Protein C zymogen (PC) administration in septic rat brain. Male Wistar rats ( n = 60) were subjected to sepsis via Cecal Ligation and Puncture (CLP). Animals were randomly divided either to receive 100 IU/kg human PC concentrate at 1, 7 and 13 h post CLP (CLP + PC group) or placebo treatment (CLP group). At pre-specified time points (6, 12, 24, 36, 48 and 60 h post CLP) five animals from either group were euthanized and the brain tissue was removed. Apoptosis in both neurons (Neu-N+) and astroglia (GFAP+) was assessed by flow cytometry using 7-aminoactinomycin D (7AAD). Immunohistochemical detection of cleaved caspase 3, bax, bcl-2, cytochrome c and caspase 8 was also performed. PC treated animals had significantly reduced apoptosis in neurons at 6 and 24 h post CLP ( p = 0.04 and p = 0.016 respectively) and necrosis at 6, 12 and 60 h post CLP ( p = 0.008, p = 0.012 and p = 0.032 respectively). Astrocyte necrosis was also decreased in septic rats receiving PC (6, 12 and 60 h post CLP p = 0.008, p = 0.016 and p = 0.008 respectively). In addition, active caspase 3, bax, cytochrome c and caspase 8 expression was significantly decreased during early sepsis (6–36 h) while bcl-2 expression was increased (24 h p = 0.001 and 60 h p = 0.001) in the PC treated animals compared to placebo. PC concentrate administration in experimental sepsis produced a time dependent inhibition of apoptosis in rat neurons and astrocytes. The inhibition of sepsis related apoptosis concerned both the mitochondrial and caspase 8 dependent pathways.