Early Immunological Effects of Ischemia-Reperfusion Injury: No Modulation by Ischemic Preconditioning in a Randomised Crossover Trial in Healthy Humans

Abstract

Ischemic preconditioning (IPC) has been protective against ischemia-reperfusion injury (IRI), but the underlying mechanism is poorly understood. We examined whether IPC modulates the early inflammatory response after IRI. Nineteen healthy males participated in a randomised crossover trial with and without IPC before IRI. IPC and IRI were performed by cuff inflation on the forearm. IPC consisted of four cycles of five minutes followed by five minutes of reperfusion. IRI consisted of twenty minutes followed by 15 min of reperfusion. Blood was collected at baseline, 0 min, 85 min and 24 h after IRI. Circulating monocytes, T-cells subsets and dendritic cells together with intracellular activation markers were quantified by flow cytometry. Luminex measured a panel of inflammation-related cytokines in plasma. IRI resulted in dynamic regulations of the measured immune cells and their intracellular activation markers, however IPC did not significantly alter these patterns. Neither IRI nor the IPC protocol significantly affected the levels of inflammatory-related cytokines. In healthy volunteers, it was not possible to detect an effect of the investigated IPC-protocol on early IRI-induced inflammatory responses. This study indicates that protective effects of IPC on IRI is not explained by direct modulation of early inflammatory events.

Dynamics of circulating dendritic cells and cytokines after kidney transplantation—No effect of remote ischaemic conditioning

“…Thus, RIC is unable to attenuate IRI in the setting of deceased donor kidney transplantation to an extent that can be detected as clinical, biochemical or immunological parameters. These findings are in line with the results of RIC in healthy volunteers, showing that there are no major immune modulations within the first 24 h after ischaemic preconditioning [28].…”

Effects of upper limb ischemia‐reperfusion on regional oxidative stress during aortic surgery with moderate hypothermia

“…Oxidative stress biomarkers seem to be far from reflecting the results of I/R damage quickly enough to be useful in surgery. A study that evaluated the effects of ischemic preconditioning on I/R injury found that inflammatory cytokine levels were not significantly affected by I/R injury 31 . It seems that inflammatory markers do not give as much information as the markers we are used to.…”

Estrogen Protects against Renal Ischemia-Reperfusion Injury by Regulating Th17/Treg Cell Immune Balance

“…There is accumulating evidence indicating that T cells, particularly CD4 + T cells, play a critical role in the pathogenesis of renal I/R [10,12,13]. However, the mechanism of T 10 Disease Markers cell infiltration during the early phase of renal IRI remains unknown.…”

“…As an acute tissue injury, renal I/R injury leads to infiltration of immune cells, which contributes to both the damage and repair processes together with resident immune cells [ 2 , 9 , 11 ]. Numerous studies have shown that T cells exploit extremely complex functions in renal ischemic response [ 10 , 12 , 13 ]. A few studies utilizing selective knockout rodents and CD4 + and/or CD8 + reconstituted T cell subsets have implicated that CD4 + cells promote damage during the early stage after ischemia [ 12 , 14 ].…”