BACKGROUND AND PURPOSE: Previous studies have suggested that delayed release of hemoglobin degradation products, particularly iron, is involved in intracerebral hemorrhage (ICH)-induced brain injury. However, a recent study found evidence of iron-induced brain injury soon after ICH. This study, therefore, examined whether another iron-containing component of blood, holo-transferrin (holo-Tf), might also induce brain injury either alone or in combination with thrombin, another factor involved in early ICH-induced brain injury. METHODS: Male Sprague-Dawley rats received an intracerebral infusion of holo-Tf, apo (noniron-loaded)-Tf, thrombin, or a combination of Tf with thrombin into the right basal ganglia. The rats were euthanized 24 hours later for measurement of brain edema and assessment of DNA damage (single- and double-strand breaks and 8-hydroxyl-2'-deoxyguanosine immunohistochemistry). Iron distribution was examined histochemically. RESULTS: Holo-Tf, apo-Tf, and the dose of thrombin used (1 U) all failed to induce brain edema when administered alone. However, the combination of holo-Tf with thrombin (but not apo-Tf with thrombin) caused brain edema, DNA damage, and intracellular iron accumulation in the ipsilateral basal ganglia. CONCLUSIONS: These results suggest that in addition to hemoglobin-bound iron, Tf-bound iron may contribute to ICH-induced brain injury and that thrombin may contribute to the latter by facilitating cellular iron uptake.
BACKGROUND AND PURPOSE: Previous studies have suggested that delayed release of hemoglobin degradation products, particularly iron, is involved in intracerebral hemorrhage (ICH)-induced brain injury. However, a recent study found evidence of iron-induced brain injury soon after ICH. This study, therefore, examined whether another iron-containing component of blood, holo-transferrin (holo-Tf), might also induce brain injury either alone or in combination with thrombin, another factor involved in early ICH-induced brain injury. METHODS: Male Sprague-Dawley rats received an intracerebral infusion of holo-Tf, apo (noniron-loaded)-Tf, thrombin, or a combination of Tf with thrombin into the right basal ganglia. The rats were euthanized 24 hours later for measurement of brain edema and assessment of DNA damage (single- and double-strand breaks and 8-hydroxyl-2'-deoxyguanosine immunohistochemistry). Iron distribution was examined histochemically. RESULTS: Holo-Tf, apo-Tf, and the dose of thrombin used (1 U) all failed to induce brain edema when administered alone. However, the combination of holo-Tf with thrombin (but not apo-Tf with thrombin) caused brain edema, DNA damage, and intracellular iron accumulation in the ipsilateral basal ganglia. CONCLUSIONS: These results suggest that in addition to hemoglobin-bound iron, Tf-bound iron may contribute to ICH-induced brain injury and that thrombin may contribute to the latter by facilitating cellular iron uptake.
Authors: David E Leaf; Mohan Rajapurkar; Suhas S Lele; Banibrata Mukhopadhyay; Emily A S Boerger; Finnian R Mc Causland; Michele F Eisenga; Karandeep Singh; Jodie L Babitt; John A Kellum; Paul M Palevsky; Marta Christov; Sushrut S Waikar Journal: J Am Soc Nephrol Date: 2019-02-08 Impact factor: 10.121
Authors: Daniel Bodmer; Kerry A Vaughan; Brad E Zacharia; Zachary L Hickman; E Sander Connolly Journal: Transl Stroke Res Date: 2012-04-12 Impact factor: 6.829