Transient Limb Ischemia Alters Serum Protein Expression in Healthy Volunteers: Complement C3 and Vitronectin May Be Involved in Organ Protection Induced by Remote Ischemic Preconditioning

Abstract

The protective mechanism underlying remote ischemic preconditioning (RIPC) is unclear. This study aims to verify whether the protein expression profile in the serum could be altered by RIPC and to detect potential protein mediators. Transient limb ischemia consisting of three cycles of 5-min ischemia followed by 5-min reperfusion was performed on sixty healthy volunteers. Serum samples were collected at 30 min before transient limb ischemia and at 1 hour (h), 3 h, 8 h, 24 h, and 48 h after completion of three cycles. Changes in the serum protein profile were analyzed by two-dimensional gel electrophoresis and proteins were identified by MALDI-TOF/TOF mass spectrometry. Fourteen differentially expressed proteins were identified and, respectively, involved in immune system, lipid binding and metabolism, apoptosis, and blood coagulation. Complement C3, vitronectin, and apolipoprotein A-I were further confirmed by western blotting, and the results showed that their contents decreased significantly after transient limb ischemia. It is concluded that transient limb ischemia alters the serum protein expression profile in human being, and that reduction of serum contents of complement C3 and vitronectin may represent an important part of the mechanism whereby RIPC confers its protection.

Exploring the Human Plasma Proteome for Humoral Mediators of Remote Ischemic Preconditioning - A Word of Caution

“…Surprisingly, only one of the given protein accession numbers could be found in both the mass spectrometry and the 2D gel result sets. Subsequently, Pang et al found 14 proteins to be differentially regulated by RIPC and validated these findings by Western blotting [18] . Notably, only one of the accessions reported, Gelsolin (UniProt accession number P06396), could be mapped to those published by Hepponstall et al Additionally, albeit with different sequences, both studies underlined the regulation of Apolipoprotein A-I.…”

Ischemic Conditioning as a Hemostatic Intervention in Surgery and Cardiac Procedures: A Systematic Review

“…82,83 No consistent effect on secondary hemostasis has been found in healthy subjects and patients as well as in patients undergoing surgery. [21][22][23]26,54,78,79 The intervention increased fibrinolysis in patients with cerebrovascular disease and chronic ischemic heart failure, 25,26 but not in healthy males, 23,24 and the effects on fibrinolysis have not Liver resection (n ¼ 7): no effect on secondary hemostasis 10,[31][32][33][34]36,37 Cardiac procedures (n ¼ 2): reduced platelet activation 41,44 PCI (n ¼ 1): no effect on MI 40 Liver resection (n ¼ 9): no effect in eight studies 10,[30][31][32][33][34]36,37 Reduced intraop. bleeding in one study 35 Cardiac surgery (n ¼ 2): no effect 42,43 Remote ischemic conditioning Liver transplantation (n ¼ 1): no effect on secondary hemostasis 54 Aneurysmal subarachnoid hemorrhage (n ¼ 1): increased PT/INR but not PTT 78 Cardiac procedures (n ¼ 2): reduced platelet activation 82,83 Vascular surgery (n ¼ 8): no effect in seven studies [45][46][47][48]…”

“…89 Remote ischemic conditioning influenced laboratory parameters of hemostasis in study participants with no ischemic event close to the intervention. 21,22,25,26,78,79 Hence, the intervention could modulate hemostasis by directly affecting platelets or the fibrinolytic system without a preceding ischemic event.…”

“…20 In addition, remote ischemic conditioning modified the serum concentration of proteins involved in secondary hemostasis in healthy subjects with no ischemic event without consistently showing a hypercoagulable or hypocoagulable direction. 21,22 Neither secondary hemostasis nor fibrinolysis was influenced by remote ischemic conditioning in a study on healthy men with no ischemic event, 23 and remote ischemic conditioning did not attenuate the fibrinolytic dysfunction following experimentally induced extremity ischemia-reperfusion injury in healthy males. 24 Longterm administration of remote ischemic conditioning has been shown to increase fibrinolysis in patients with chronic ischemic heart failure, 25 as well as increase fibrinolysis and reduce platelet aggregation in patients with cerebrovascular disease.…”

Exploring effects of remote ischemic preconditioning in a pig model of hypothermic circulatory arrest

“…Particular interest was given to samples from sagittal sinus because they were taken behind the blood-brain barrier. Based on previous literature on protein functions and possible relevance to RIPC [19,21,30] we selected 4 proteins:, apolipoprotein E (APOE), complement C3 (C3), transthyretin (TTR) and vitronectin (VTN), to be validated by ELISA. The levels of these four proteins were, however, not significantly changed between the RIPC and control groups at any of the studied time points ( Figure 6).…”