Spleen tyrosine kinase inhibition prevents tissue damage after ischemia-reperfusion.
Reperfusion injury to tissue following an ischemic event occurs as a consequence of an acute inflammatory response that can cause significant morbidity and mortality. Components of both the innate (complement, immunoglobulin, monocytes, and neutrophils) and adaptive (B and T lymphocytes) immune systems have been demonstrated to mediate tissue injury. Spleen tyrosine kinase (Syk) is responsible for membrane-mediated signaling in various cell types including B lymphocytes, macrophages, and T cells. We investigated the ability of a small drug Syk inhibitor, R788, to protect mice against mesenteric ischemia-reperfusion (I/R)-induced local (intestine) and remote lung injury. Mice were fed with chow containing a Syk inhibitor for 6 days before the performance of intestinal I/R, which resulted in silencing of the expression of the active phosphorylated Syk. Syk inhibition significantly suppressed both local and remote lung injury. The beneficial effect was associated with reduced IgM and complement 3 deposition in the tissues and significant reduction of polymorphonuclear cell infiltration. Our data place Syk upstream of events leading to the binding of natural antibodies to the ischemia-conditioned tissues and urge the consideration of the use of Syk inhibitors in the prevention or improvement of tissue injury of organs exposed to ischemia or hypoperfusion.
Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA.
Omer Nuri
ON
Pamuk
Peter H
PH
Lapchak
Poonam
P
Rani
Polly
P
Pine
Jurandir J
JJ
Dalle Lucca
George C
GC
Tsokos
D000631:Aminopyridines; D000818:Animals; D003176:Complement C3 / Q000037:antagonists & inhibitors / Q000378:metabolism; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007074:Immunoglobulin G / Q000378:metabolism; D007075:Immunoglobulin M / Q000378:metabolism; D007422:Intestines / Q000098:blood supply / Q000187:drug effects / Q000473:pathology; D047908:Intracellular Signaling Peptides and Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008168:Lung / Q000201:enzymology / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D009025:Morpholines; D020556:Neutrophil Infiltration; D010078:Oxazines / Q000494:pharmacology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011652:Pulmonary Circulation; D011725:Pyridines / Q000494:pharmacology; D011743:Pyrimidines; D011956:Receptors, Cell Surface / Q000378:metabolism; D015427:Reperfusion Injury / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology*; D013152:Splanchnic Circulation; D000072377:Syk Kinase
D000631:Aminopyridines; D003176:Complement C3; D004791:Enzyme Inhibitors; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D047908:Intracellular Signaling Peptides and Proteins; D009025:Morpholines; D010078:Oxazines; D011725:Pyridines; D011743:Pyrimidines; D011956:Receptors, Cell Surface; C551746:granulocyte receptor 1, mouse; D011505:Protein-Tyrosine Kinases; D000072377:Syk Kinase; C000606897:Syk protein, mouse; C523665:fostamatinib