Bong Jun Kim1, Youngmi Kim1, Sung-Eun Kim2, Jin Pyeong Jeon3. 1. Institute of New Frontier Research, Hallym University College of Medicine, Chuncheon, Korea. 2. Department of Emergency Medicine, Seoul Emergency Operations Center, Seoul, Korea. 3. Institute of New Frontier Research, Hallym University College of Medicine, Chuncheon, Korea; Department of Neurosurgery, Hallym University College of Medicine, Chuncheon, Korea. Electronic address: jjs6553@daum.net.
Abstract
BACKGROUND: Haptoglobin (Hp) comprising 2 light (α) and 2 heavy (β) chains has an antioxidant effect following free hemoglobin binding. Among 3 phenotypes-Hp1-1 (two α1), Hp2-1 (α1 and α2), and Hp2-2 (two α2)-a greater protective effect for toxic-free hemoglobin was reported for Hp2-2 compared with Hp1-1. However, few studies have focused on the association of Hp2-1 with outcomes. This study examined α1 and α2 expression, and evaluated the correlation of Hp2-1 with outcomes of subarachnoid hemorrhage (SAH). METHODS: Eighty-seven patients were enrolled prospectively, including 12 in the Hp1-1 group (13.8%), 36 in the Hp2-1 group (41.4%), and 39 in the Hp2-2 group (44.8%). Phenotypes were confirmed by Western blot analysis. The relative band intensities were measured as α subunit intensities normalized to albumin intensities and expressed as median (interquartile range). The differences in α intensities according to delayed cerebral ischemia (DCI), angiographic vasospasm (AV), and outcome were analyzed. RESULTS: DCI and AV were more frequently associated with Hp2-2 than with Hp1-1 (DCI: 21 [53.8%] vs. 3 [25.0%]; AV: 22 [56.4%] vs. 3 [25.0%]). The α1 intensities of Hp2-1 without DCI and AV were significantly higher than those with DCI and AV (without DCI: 0.70 [interquartile range (IQR), 0.54-0.89]; with DCI: 0.24 [IQR, 0.14-0.32]; P < 0.001; without AV: 0.65 [IQR, 0.32-0.88]; with AV: 0.32 [IQR, 0.17-0.67]; P = 0.046). No significant difference was noted with α2 intensities. The α1 (P = 0.359) and α2 (P = 0.233) intensities did not differ significantly according to outcome. CONCLUSIONS: Higher α1 intensities in Hp2-1 are associated with a lower risk of DCI and AV. The degree of α1 intensity may provide additional information about the individual risk of secondary injury following SAH in patients with Hp2-1.
BACKGROUND:Haptoglobin (Hp) comprising 2 light (α) and 2 heavy (β) chains has an antioxidant effect following free hemoglobin binding. Among 3 phenotypes-Hp1-1 (two α1), Hp2-1 (α1 and α2), and Hp2-2 (two α2)-a greater protective effect for toxic-free hemoglobin was reported for Hp2-2 compared with Hp1-1. However, few studies have focused on the association of Hp2-1 with outcomes. This study examined α1 and α2 expression, and evaluated the correlation of Hp2-1 with outcomes of subarachnoid hemorrhage (SAH). METHODS: Eighty-seven patients were enrolled prospectively, including 12 in the Hp1-1 group (13.8%), 36 in the Hp2-1 group (41.4%), and 39 in the Hp2-2 group (44.8%). Phenotypes were confirmed by Western blot analysis. The relative band intensities were measured as α subunit intensities normalized to albumin intensities and expressed as median (interquartile range). The differences in α intensities according to delayed cerebral ischemia (DCI), angiographic vasospasm (AV), and outcome were analyzed. RESULTS: DCI and AV were more frequently associated with Hp2-2 than with Hp1-1 (DCI: 21 [53.8%] vs. 3 [25.0%]; AV: 22 [56.4%] vs. 3 [25.0%]). The α1 intensities of Hp2-1 without DCI and AV were significantly higher than those with DCI and AV (without DCI: 0.70 [interquartile range (IQR), 0.54-0.89]; with DCI: 0.24 [IQR, 0.14-0.32]; P < 0.001; without AV: 0.65 [IQR, 0.32-0.88]; with AV: 0.32 [IQR, 0.17-0.67]; P = 0.046). No significant difference was noted with α2 intensities. The α1 (P = 0.359) and α2 (P = 0.233) intensities did not differ significantly according to outcome. CONCLUSIONS: Higher α1 intensities in Hp2-1 are associated with a lower risk of DCI and AV. The degree of α1 intensity may provide additional information about the individual risk of secondary injury following SAH in patients with Hp2-1.
Authors: Ben Gaastra; Dianxu Ren; Sheila Alexander; Ellen R Bennett; Dawn M Bielawski; Spiros L Blackburn; Mark K Borsody; Sylvain Doré; James Galea; Patrick Garland; Tian He; Koji Iihara; Yoichiro Kawamura; Jenna L Leclerc; James F Meschia; Michael A Pizzi; Rafael J Tamargo; Wuyang Yang; Paul A Nyquist; Diederik O Bulters; Ian Galea Journal: Neurology Date: 2019-04-05 Impact factor: 9.910