1
|
Dreier JP, Joerk A, Uchikawa H, Horst V, Lemale CL, Radbruch H, McBride DW, Vajkoczy P, Schneider UC, Xu R. All Three Supersystems-Nervous, Vascular, and Immune-Contribute to the Cortical Infarcts After Subarachnoid Hemorrhage. Transl Stroke Res 2024:10.1007/s12975-024-01242-z. [PMID: 38689162 DOI: 10.1007/s12975-024-01242-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 03/12/2024] [Accepted: 03/14/2024] [Indexed: 05/02/2024]
Abstract
The recently published DISCHARGE-1 trial supports the observations of earlier autopsy and neuroimaging studies that almost 70% of all focal brain damage after aneurysmal subarachnoid hemorrhage are anemic infarcts of the cortex, often also affecting the white matter immediately below. The infarcts are not limited by the usual vascular territories. About two-fifths of the ischemic damage occurs within ~ 48 h; the remaining three-fifths are delayed (within ~ 3 weeks). Using neuromonitoring technology in combination with longitudinal neuroimaging, the entire sequence of both early and delayed cortical infarct development after subarachnoid hemorrhage has recently been recorded in patients. Characteristically, cortical infarcts are caused by acute severe vasospastic events, so-called spreading ischemia, triggered by spontaneously occurring spreading depolarization. In locations where a spreading depolarization passes through, cerebral blood flow can drastically drop within a few seconds and remain suppressed for minutes or even hours, often followed by high-amplitude, sustained hyperemia. In spreading depolarization, neurons lead the event, and the other cells of the neurovascular unit (endothelium, vascular smooth muscle, pericytes, astrocytes, microglia, oligodendrocytes) follow. However, dysregulation in cells of all three supersystems-nervous, vascular, and immune-is very likely involved in the dysfunction of the neurovascular unit underlying spreading ischemia. It is assumed that subarachnoid blood, which lies directly on the cortex and enters the parenchyma via glymphatic channels, triggers these dysregulations. This review discusses the neuroglial, neurovascular, and neuroimmunological dysregulations in the context of spreading depolarization and spreading ischemia as critical elements in the pathogenesis of cortical infarcts after subarachnoid hemorrhage.
Collapse
Affiliation(s)
- Jens P Dreier
- Center for Stroke Research Berlin, Campus Charité Mitte, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany.
- Department of Experimental Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.
- Department of Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.
- Bernstein Center for Computational Neuroscience Berlin, Berlin, Germany.
- Einstein Center for Neurosciences Berlin, Berlin, Germany.
| | - Alexander Joerk
- Department of Neurology, Jena University Hospital, Jena, Germany
| | - Hiroki Uchikawa
- Barrow Aneurysm & AVM Research Center, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, USA
| | - Viktor Horst
- Center for Stroke Research Berlin, Campus Charité Mitte, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany
- Institute of Neuropathology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Coline L Lemale
- Center for Stroke Research Berlin, Campus Charité Mitte, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Germany
- Department of Experimental Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Helena Radbruch
- Institute of Neuropathology, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Devin W McBride
- The Vivian L. Smith Department of Neurosurgery, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Peter Vajkoczy
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Ulf C Schneider
- Department of Neurosurgery, Cantonal Hospital of Lucerne and University of Lucerne, Lucerne, Switzerland
| | - Ran Xu
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
- DZHK, German Centre for Cardiovascular Research, Berlin, Germany
| |
Collapse
|
2
|
Yu FF, Yuan Y, Ao Y, Hua L, Wang W, Cao Y, Xi J, Luan Y, Hou S, Zhang XY. A New Product of Bilirubin Degradation by H 2O 2 and Its Formation in Activated Neutrophils and in an Inflammatory Mouse Model. Biomolecules 2022; 12:biom12091237. [PMID: 36139076 PMCID: PMC9496627 DOI: 10.3390/biom12091237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 08/26/2022] [Accepted: 09/01/2022] [Indexed: 11/17/2022] Open
Abstract
Bilirubin (BR) is a tetrapyrrolic compound stemming from heme catabolism with diverse physiological functions. It can be oxidized by H2O2 to form several degradation products, some of which have been detected in vivo and may contribute to the pathogenesis of certain diseases. However, the oxidative degradation of BR is complex and the conditions that BR degradation occurs pathophysiologically remain obscure. Neutrophils are known to generate large amounts of reactive oxygen species, including H2O2, upon activation and they are mobilized to inflammatory sites; therefore, we hypothesized that activated neutrophils could cause BR degradation, which could occur at inflammatory sites. In the present study, we investigated BR degradation by H2O2 and identified hematinic acid (BHP1) and a new product BHP2, whose structure was characterized as 2,5-diformyl-4-methyl-1H-pyrrole-3-propanoic acid. An LC-MS/MS method for the quantitation of the two compounds was then established. Using the LC-MS/MS method, we observed the concentration-dependent formation of BHP1 and BHP2 in mouse neutrophils incubated with 10 and 30 μM of BR with the yields being 16 ± 3.2 and 31 ± 5.9 pmol/106 cells for BHP1, and 25 ± 4.4 and 71 ± 26 pmol/106 cells for BHP2, respectively. After adding phorbol 12-myristate 13-acetate, a neutrophil agonist, to 30 μM of BR-treated cells, the BHP1 yield increased to 43 ± 6.6 pmol/106 cells, whereas the BHP2 one decreased to 47 ± 9.2 pmol/106 cells. The two products were also detected in hemorrhagic skins of mice with dermal inflammation and hemorrhage at levels of 4.5 ± 1.9 and 0.18 ± 0.10 nmol/g tissue, respectively, which were significantly higher than those in the non-hemorrhagic skins. BHP2 was neurotoxic starting at 0.10 μM but BHP1 was not, as assessed using Caenorhabditis elegans as the animal model. Neutrophil-mediated BR degradation may be a universally pathophysiological process in inflammation and can be particularly important under pathological conditions concerning hemorrhage.
Collapse
Affiliation(s)
- Fei-Fei Yu
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Yao Yuan
- Shanghai Jiao Tong University-Hangzhou Future Sci-Tech City Joint Research Center for Tumor Immunotherapy, Hangzhou Innovation Institute for Systems Oncology, Hangzhou 311121, China
| | - Yan Ao
- Ministry of Education-Shanghai Key Laboratory of Children’s Environmental Health, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China
| | - Li Hua
- School of Public Health, Hongqiao International Institute of Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Wu Wang
- Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
- Correspondence: (W.W.); (S.H.); (X.-Y.Z.)
| | - Yiyi Cao
- School of Public Health, Hongqiao International Institute of Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Jing Xi
- School of Public Health, Hongqiao International Institute of Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Yang Luan
- School of Public Health, Hongqiao International Institute of Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Shangwei Hou
- Shanghai Jiao Tong University-Hangzhou Future Sci-Tech City Joint Research Center for Tumor Immunotherapy, Hangzhou Innovation Institute for Systems Oncology, Hangzhou 311121, China
- Correspondence: (W.W.); (S.H.); (X.-Y.Z.)
| | - Xin-Yu Zhang
- School of Public Health, Hongqiao International Institute of Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
- Correspondence: (W.W.); (S.H.); (X.-Y.Z.)
| |
Collapse
|
3
|
Liu J, Kong L, Chen D, Tang H, Lu Y, Yuan Y, Qian F, Hou S, Zhao W, Zhang M. Bilirubin oxidation end product B prevents CoCl 2-induced primary cortical neuron apoptosis by promoting cell survival Akt/mTOR/p70S6K signaling pathway. Biochem Biophys Res Commun 2022; 602:27-34. [PMID: 35247701 DOI: 10.1016/j.bbrc.2022.02.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 01/12/2023]
Abstract
Bilirubin oxidation end products (BOXes) are associated with the late-developing neurological deficits after subarachnoid hemorrhage (SAH) possibly by direct constricting the cerebral arteries, but their specific impacts on neurons especially in the state of hypoxia, a prominent feature during the late stage of SAH, remain unclear. Here, we explored the effects of BOXes on the primary cortical neurons subjected to CoCl2-induced hypoxia by evaluating the morphological and apoptotic changes of neurons. The present study showed that Z-BOX B but not Z-BOX A greatly alleviated CoCl2-induced neuronal cell deterioration and apoptosis. Immunocytochemical staining assay showed Z-BOX B significantly increased neurite length, the numbers of both secondary and tertiary branches, and the protein level of Synaptophysin. Caspase 3/7 apoptosis assay and DAPI staining showed that Z-BOX B markedly reduced primary cortical neurons apoptosis. The expression of cleaved Caspase-3 was suppressed by Z-BOX B treatment, while the expression of Bcl-xL was upregulated. To further discover the mechanism of the neuroprotective effect observed in Z-BOX B, we found Z-BOX B increased the expression of p-mTOR, p-Akt, and p-p70S6K. In general, our results implicated Z-BOX B may prevent CoCl2-induced primary cortical neurons apoptosis by activating sAkt/mTOR/p70S6K signaling pathway. Hence, the present data may provide new insights into the pathophysiological mechanism of delayed neurological dysfunction after SAH and novel targets for treating SAH.
Collapse
Affiliation(s)
- Jingting Liu
- Pharm-X Center, Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, PR China
| | - Lingxuan Kong
- Department of Physical Education, Shanghai Jiao Tong University, Shanghai, PR China
| | - Dongxin Chen
- Pharm-X Center, Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, PR China
| | - Huirong Tang
- Pharm-X Center, Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, PR China
| | - Yinzhong Lu
- Department of Anesthesiology and Hongqiao International Institute of Medicine, Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200336, PR China
| | - Yao Yuan
- Pharm-X Center, Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, PR China
| | - Feng Qian
- Pharm-X Center, Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, PR China
| | - Shangwei Hou
- Hongqiao International Institute of Medicine, Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, PR China
| | - Wenjuan Zhao
- Pharm-X Center, Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, PR China.
| | - Man Zhang
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, PR China.
| |
Collapse
|
4
|
Bilirubin Oxidation End Products (BOXes) Induce Neuronal Oxidative Stress Involving the Nrf2 Pathway. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:8869908. [PMID: 34373769 PMCID: PMC8349295 DOI: 10.1155/2021/8869908] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 06/04/2021] [Accepted: 06/22/2021] [Indexed: 11/25/2022]
Abstract
Delayed ischemic neurological deficit (DIND) is a severe complication after subarachnoid hemorrhage (SAH). Previous studies have suggested that bilirubin oxidation end products (BOXes) are probably associated with the DIND after SAH, but there is a lack of direct evidence yet even on cellular levels. In the present study, we aim to explore the potential role of BOXes and the involved mechanisms in neuronal function. We synthesized high-purity (>97%) BOX A and BOX B isomers. The pharmacokinetics showed they are permeable to the blood-brain barrier. Exposure of a moderate concentration (10 or 30 μM) of BOX A or BOX B to isolated primary cortical neurons increased the production of reactive oxygen species. In the human neuroblastoma SH-SY5Y cells, BOX A and BOX B decreased the mitochondrial membrane potential and enhanced nuclear accumulation of the protein Nrf2 implicated in oxidative injury repair. In addition, both chemicals increased the mRNA and protein expression levels of multiple antioxidant response genes including Hmox1, Gsta3, Blvrb, Gclm, and Srxn1, indicating that the antioxidant response element (ARE) transcriptional cascade driven by Nrf2 is activated. In conclusion, we demonstrated that primary cortical neurons and neuroblastoma cells undergo an adaptive response against BOX A- and BOX B-mediated oxidative stress by activation of multiple antioxidant responses, in part through the Nrf2 pathway, which provides in-depth insights into the pathophysiological mechanism of DIND after SAH or other neurological dysfunctions related to cerebral hemorrhage.
Collapse
|
5
|
Schulze D, Klopfleisch M, Görls H, Westerhausen M. BOX A-type monopyrrolic heterocycles modified via the Suzuki-Miyaura cross-coupling reaction. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2019. [DOI: 10.1515/znb-2019-0125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The in vivo oxidation of heme yields bilirubin which is further degraded to the bilirubin oxidation end products (BOXes) that are biologically highly active. To study the mode of action and fate of (Z)-2-(4-methyl-5-oxo-3-vinyl-1,5-dihydro-2H-pyrrol-2-ylidene)acetamide (BOX A), the Suzuki-Miyaura cross-coupling reaction allows to introduce various alkenyl- and aryl-substituents in 3-position of the (Z)-2-(4-methyl-5-oxo-1,5-dihydro-2H-pyrrol-2-ylidene)acetamides (BOX A-type monopyrroles). The influence of these groups on structural and NMR-spectroscopic parameters of the central monopyrrolic system is negligible. Special focus has been given to derivatives with 3-positioned aryl substituents carrying trifluoromethyl groups for future in vivo
19F NMR studies.
Collapse
Affiliation(s)
- Daniel Schulze
- Friedrich Schiller University Jena , Chair of Inorganic Chemistry 1 , Humboldtstraße 8 , D-07743 Jena , Germany
| | - Maurice Klopfleisch
- Otto von Guericke University , Medicinal Faculty, Clinic for Radiology and Nuclear Medicine , D-39120 Magdeburg , Germany
| | - Helmar Görls
- Friedrich Schiller University Jena , Chair of Inorganic Chemistry 1 , Humboldtstraße 8 , D-07743 Jena , Germany
| | - Matthias Westerhausen
- Friedrich Schiller University Jena , Chair of Inorganic Chemistry 1 , Humboldtstraße 8 , D-07743 Jena , Germany , Fax: +49 (0) 3641-9-48132
| |
Collapse
|
6
|
24S-hydroxycholesterol alters activity of large-conductance Ca 2+-dependent K + (slo1 BK) channel through intercalation into plasma membrane. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:1525-1535. [PMID: 31136842 DOI: 10.1016/j.bbalip.2019.05.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 05/11/2019] [Accepted: 05/20/2019] [Indexed: 11/24/2022]
Abstract
Oxysterols, oxidization products of cholesterol, are regarded as bioactive lipids affecting various physiological functions. However, little is known of their effects on ion channels. Using inside-out patch clamp recording, we found that naturally occurring side-chain oxidized oxysterols, 20S‑hydroxycholesterol, 22R‑hydroxycholesterol, 24S‑hydroxycholestero, 25‑hydroxycholesterol, and 27‑hydroxycholesterol, induced current reduction of large-conductance Ca2+- and voltage-activated K+ (slo1 BK) channels heterologously expressed in HEK293T cells. In contrast with side-chain oxidized oxysterols, naturally occurring ring oxidized ones, 7α‑hydroxycholesterol and 7‑ketocholesterol were without effect. By using 24S‑hydroxycholesterol (24S‑HC), the major brain oxysterol, we explored the inhibition mechanism. 24S‑HC inhibited Slo1 BK channels with an IC50 of ~2 μM, and decreased macroscopic current by ~60%. This marked current decrease was accompanied by a rightward shift in the conductance-voltage relationship and a slowed activation kinetics, with the deactivation kinetics unaltered. Furthermore, the membrane sterol scavenger γ‑cyclodextrin was found to rescue slo1 BK channels from the inhibition, implicating that 24S-HC may be intercalated into the plasma membrane to affect the channel. These findings unveil a novel physiological importance of oxysterols from a new angle that involves ion channel regulation.
Collapse
|
7
|
Joerk A, Ritter M, Langguth N, Seidel RA, Freitag D, Herrmann KH, Schaefgen A, Ritter M, Günther M, Sommer C, Braemer D, Walter J, Ewald C, Kalff R, Reichenbach JR, Westerhausen M, Pohnert G, Witte OW, Holthoff K. Propentdyopents as Heme Degradation Intermediates Constrict Mouse Cerebral Arterioles and Are Present in the Cerebrospinal Fluid of Patients With Subarachnoid Hemorrhage. Circ Res 2019; 124:e101-e114. [PMID: 30947629 DOI: 10.1161/circresaha.118.314160] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
RATIONALE Delayed ischemic neurological deficit is the most common cause of neurological impairment and unfavorable prognosis in patients with subarachnoid hemorrhage (SAH). Despite the existence of neuroimaging modalities that depict the onset of the accompanying cerebral vasospasm, preventive and therapeutic options are limited and fail to improve outcome owing to an insufficient pathomechanistic understanding of the delayed perfusion deficit. Previous studies have suggested that BOXes (bilirubin oxidation end products), originating from released heme surrounding ruptured blood vessels, are involved in arterial vasoconstriction. Recently, isolated intermediates of oxidative bilirubin degradation, known as PDPs (propentdyopents), have been considered as potential additional effectors in the development of arterial vasoconstriction. OBJECTIVE To investigate whether PDPs and BOXes are present in hemorrhagic cerebrospinal fluid and involved in the vasoconstriction of cerebral arterioles. METHODS AND RESULTS Via liquid chromatography/mass spectrometry, we measured increased PDP and BOX concentrations in cerebrospinal fluid of SAH patients compared with control subjects. Using differential interference contrast microscopy, we analyzed the vasoactivity of PDP isomers in vitro by monitoring the arteriolar diameter in mouse acute brain slices. We found an arteriolar constriction on application of PDPs in the concentration range that occurs in the cerebrospinal fluid of patients with SAH. By imaging arteriolar diameter changes using 2-photon microscopy in vivo, we demonstrated a short-onset vasoconstriction after intrathecal injection of either PDPs or BOXes. Using magnetic resonance imaging, we observed a long-term PDP-induced delay in cerebral perfusion. For all conditions, the arteriolar narrowing was dependent on functional big conductance potassium channels and was absent in big conductance potassium channels knockout mice. CONCLUSIONS For the first time, we have quantified significantly higher concentrations of PDP and BOX isomers in the cerebrospinal fluid of patients with SAH compared to controls. The vasoconstrictive effect caused by PDPs in vitro and in vivo suggests a hitherto unrecognized pathway contributing to the pathogenesis of delayed ischemic deficit in patients with SAH.
Collapse
Affiliation(s)
- Alexander Joerk
- From the Hans Berger Department of Neurology (A.J., N.L., A.S., Marvin Ritter, M.G., C.S., D.B., O.W.W., K.H.), Jena University Hospital, Germany.,Research Program Else Kröner-Forschungskolleg AntiAge (A.J.), Jena University Hospital, Germany
| | | | - Niklas Langguth
- From the Hans Berger Department of Neurology (A.J., N.L., A.S., Marvin Ritter, M.G., C.S., D.B., O.W.W., K.H.), Jena University Hospital, Germany
| | - Raphael Andreas Seidel
- Department of Anesthesiology and Intensive Care Medicine / Center for Sepsis Control and Care (R.A.S.), Jena University Hospital, Germany.,Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, Germany (Marcel Ritter, R.A.S., M.W., G.P.)
| | - Diana Freitag
- Department of Neurosurgery (D.F., J.W., R.K.), Jena University Hospital, Germany
| | - Karl-Heinz Herrmann
- Medical Physics Group, Institute for Diagnostic and Interventional Radiology, Jena University Hospital, Germany (K.-H.H., J.R.R.)
| | - Anna Schaefgen
- From the Hans Berger Department of Neurology (A.J., N.L., A.S., Marvin Ritter, M.G., C.S., D.B., O.W.W., K.H.), Jena University Hospital, Germany
| | - Marvin Ritter
- From the Hans Berger Department of Neurology (A.J., N.L., A.S., Marvin Ritter, M.G., C.S., D.B., O.W.W., K.H.), Jena University Hospital, Germany
| | - Milena Günther
- From the Hans Berger Department of Neurology (A.J., N.L., A.S., Marvin Ritter, M.G., C.S., D.B., O.W.W., K.H.), Jena University Hospital, Germany
| | - Charline Sommer
- From the Hans Berger Department of Neurology (A.J., N.L., A.S., Marvin Ritter, M.G., C.S., D.B., O.W.W., K.H.), Jena University Hospital, Germany
| | - Dirk Braemer
- From the Hans Berger Department of Neurology (A.J., N.L., A.S., Marvin Ritter, M.G., C.S., D.B., O.W.W., K.H.), Jena University Hospital, Germany
| | - Jan Walter
- Department of Neurosurgery (D.F., J.W., R.K.), Jena University Hospital, Germany
| | - Christian Ewald
- Department of Neurosurgery, Brandenburg Medical School, Campus Brandenburg an der Havel, Germany (C.E.)
| | - Rolf Kalff
- Department of Neurosurgery (D.F., J.W., R.K.), Jena University Hospital, Germany
| | - Jürgen Rainer Reichenbach
- Medical Physics Group, Institute for Diagnostic and Interventional Radiology, Jena University Hospital, Germany (K.-H.H., J.R.R.)
| | - Matthias Westerhausen
- Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, Germany (Marcel Ritter, R.A.S., M.W., G.P.)
| | - Georg Pohnert
- Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, Germany (Marcel Ritter, R.A.S., M.W., G.P.)
| | - Otto Wilhelm Witte
- From the Hans Berger Department of Neurology (A.J., N.L., A.S., Marvin Ritter, M.G., C.S., D.B., O.W.W., K.H.), Jena University Hospital, Germany
| | - Knut Holthoff
- From the Hans Berger Department of Neurology (A.J., N.L., A.S., Marvin Ritter, M.G., C.S., D.B., O.W.W., K.H.), Jena University Hospital, Germany
| |
Collapse
|
8
|
Harris NA, Rapoport RM, Zuccarello M, Maggio JE. UV light absorption parameters of the pathobiologically implicated bilirubin oxidation products, MVM, BOX A, and BOX B. Data Brief 2018; 18:1400-1409. [PMID: 29900321 PMCID: PMC5997574 DOI: 10.1016/j.dib.2018.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 03/24/2018] [Accepted: 04/03/2018] [Indexed: 10/29/2022] Open
Abstract
The formation of the bilirubin oxidation products (BOXes), BOX A ([4-methyl-5-oxo-3-vinyl-(1,5-dihydropyrrol-2-ylidene)acetamide]) and BOX B (3-methyl-5-oxo-4-vinyl-(1,5-dihydropyrrol-2-ylidene)acetamide), as well as MVM (4-methyl-3-vinylmaleimide) were synthesized by oxidation of bilirubin with H2O2 without and with FeCl3, respectively. Compound identity was confirmed with NMR and mass spectrometry (MS; less than 1 ppm, tandem MS up to MS4). UV absorption profiles, including λmax, and extinction coefficient (ε; estimated using NMR) for BOX A, BOX B, and MVM in H2O, 15% CH3CN plus 10 mM CF3CO2H, CH3CN, CHCl3, CH2Cl2, and 0.9% NaCl were determined. At longer wavelengths, λmax's for 1) BOX A were little affected by the solvent, ranging from 295-297 nm; 2) BOX B, less polar solvent yielded λmax's of lower wavelength, with values ranging from 308-313 nm, and 3) MVM, less polar solvent yielded λmax's of higher wavelength, with values ranging from 318-327 nm. Estimated ε's for BOX A and BOX B were approximately 5- to 10-fold greater than for MVM.
Collapse
Affiliation(s)
- Nathaniel A Harris
- Department of Pharmacology and Cell Biophysics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA.,Research Service, Veterans Affairs Medical Center, Cincinnati, OH, USA
| | - Robert M Rapoport
- Department of Pharmacology and Cell Biophysics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA.,Research Service, Veterans Affairs Medical Center, Cincinnati, OH, USA
| | - Mario Zuccarello
- Department of Neurosurgery, College of Medicine, University of Cincinnati, Cincinnati, OH, USA.,Surgical Service, Veterans Affairs Medical Center, Cincinnati, OH, USA
| | - John E Maggio
- Department of Pharmacology and Cell Biophysics, College of Medicine, University of Cincinnati, Cincinnati, OH, USA
| |
Collapse
|
9
|
Rapoport RM. Bilirubin Oxidation Products and Cerebral Vasoconstriction. Front Pharmacol 2018; 9:303. [PMID: 29755343 PMCID: PMC5934420 DOI: 10.3389/fphar.2018.00303] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 03/15/2018] [Indexed: 01/15/2023] Open
Abstract
Key evidence in support of the hypothesis that bilirubin oxidation products (BOXes) contribute to the vasoconstriction associated with subarachnoid hemorrhage (SAH) are the (1) presence of BOXes in cerebral spinal fluid from SAH patients and (2) ability of one or more BOXes to elicit vasoconstriction. We critically evaluate this key evidence, detail where gaps remain, and describe recent approaches that will address these gaps.
Collapse
Affiliation(s)
- Robert M Rapoport
- Department of Pharmacology and Systems Physiology, College of Medicine, University of Cincinnati, Cincinnati, OH, United States
| |
Collapse
|
10
|
Bulmer AC, Bakrania B, Du Toit EF, Boon AC, Clark PJ, Powell LW, Wagner KH, Headrick JP. Bilirubin acts as a multipotent guardian of cardiovascular integrity: more than just a radical idea. Am J Physiol Heart Circ Physiol 2018; 315:H429-H447. [PMID: 29600900 DOI: 10.1152/ajpheart.00417.2017] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Bilirubin, a potentially toxic catabolite of heme and indicator of hepatobiliary insufficiency, exhibits potent cardiac and vascular protective properties. Individuals with Gilbert's syndrome (GS) may experience hyperbilirubinemia in response to stressors including reduced hepatic bilirubin excretion/increased red blood cell breakdown, with individuals usually informed by their clinician that their condition is of little consequence. However, GS appears to protect from all-cause mortality, with progressively elevated total bilirubin associated with protection from ischemic heart and chronic obstructive pulmonary diseases. Bilirubin may protect against these diseases and associated mortality by reducing circulating cholesterol, oxidative lipid/protein modifications, and blood pressure. In addition, bilirubin inhibits platelet activation and protects the heart from ischemia-reperfusion injury. These effects attenuate multiple stages of the atherosclerotic process in addition to protecting the heart during resultant ischemic stress, likely underpinning the profound reduction in cardiovascular mortality in hyperbilirubinemic GS. This review outlines our current knowledge of and uses for bilirubin in clinical medicine and summarizes recent progress in revealing the physiological importance of this poorly understood molecule. We believe that this review will be of significant interest to clinicians, medical researchers, and individuals who have GS.
Collapse
Affiliation(s)
- Andrew C Bulmer
- School of Medical Science and Menzies Health Institute Queensland, Griffith University , Gold Coast, Queensland , Australia
| | - Bhavisha Bakrania
- Department of Physiology and Biophysics, University of Mississippi Medical Centre , Jackson, Mississippi
| | - Eugene F Du Toit
- School of Medical Science and Menzies Health Institute Queensland, Griffith University , Gold Coast, Queensland , Australia
| | - Ai-Ching Boon
- School of Medical Science and Menzies Health Institute Queensland, Griffith University , Gold Coast, Queensland , Australia
| | - Paul J Clark
- QIMR-Berghofer Medical Research Institute, School of Medicine, University of Queensland and Princess Alexandra and Mater Hospitals , Brisbane, New South Wales , Australia
| | - Lawrie W Powell
- The Centre for the Advancement of Clinical Research, Royal Brisbane and Women's Hospital, The University of Queensland Centre for Clinical Research , Brisbane, Queensland , Australia
| | - Karl-Heinz Wagner
- Department of Nutritional Science, University of Vienna , Vienna , Austria
| | - John P Headrick
- School of Medical Science and Menzies Health Institute Queensland, Griffith University , Gold Coast, Queensland , Australia
| |
Collapse
|
11
|
Albanna W, Neumaier F, Lüke JN, Kotliar K, Conzen C, Lindauer U, Hescheler J, Clusmann H, Schneider T, Schubert GA. Unconjugated bilirubin modulates neuronal signaling only in wild-type mice, but not after ablation of the R-type/Ca v 2.3 voltage-gated calcium channel. CNS Neurosci Ther 2017; 24:222-230. [PMID: 29274300 DOI: 10.1111/cns.12791] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 12/04/2017] [Accepted: 12/04/2017] [Indexed: 01/30/2023] Open
Abstract
INTRODUCTION The relationship between blood metabolites and hemoglobin degradation products (BMHDPs) formed in the cerebrospinal fluid and the development of vasospasm and delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH) has been the focus of several previous studies, but their molecular and cellular targets remain to be elucidated. METHODS Because BMHDP-induced changes in Cav 2.3 channel function are thought to contribute to DCI after aSAH, we studied their modulation by unconjugated bilirubin (UCB) in an organotypical neuronal network from wild-type (WT) and Cav 2.3-deficient animals (KO). Murine retinae were isolated from WT and KO and superfused with nutrient solution. Electroretinograms were recorded before, during, and after superfusion with UCB. Transretinal signaling was analyzed as b-wave, implicit time, and area under the curve (AUC). RESULTS Superfusion of UCB significantly attenuated the b-wave amplitude in the isolated retina from wild-type mice by 14.9% (P < 0.05), followed by gradual partial recovery (P = 0.09). Correspondingly, AUC decreased significantly with superfusion of UCB (P < 0.05). During washout, the b-wave amplitude returned to baseline (P = 0.2839). The effects of UCB were absent in Cav 2.3-deficient mice, lacking the expression of Cav 2.3 as proofed on the biochemical level. CONCLUSIONS Ex vivo neuronal recording in the murine retina is able to detect transient impairment of transretinal signaling by UCB in WT, but not in KO. This new model may be useful to further clarify the role of calcium channels in neuronal signal alteration in the presence of BHMDPs.
Collapse
Affiliation(s)
- Walid Albanna
- Institute for Neurophysiology, University of Cologne, Cologne, Germany.,Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
| | - Felix Neumaier
- Institute for Neurophysiology, University of Cologne, Cologne, Germany
| | - Jan Niklas Lüke
- Institute for Neurophysiology, University of Cologne, Cologne, Germany
| | - Konstantin Kotliar
- Department of Medical Engineering and Technomathematics, FH Aachen University of Applied Sciences, Aachen, Germany
| | - Catharina Conzen
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
| | - Ute Lindauer
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
| | - Jürgen Hescheler
- Institute for Neurophysiology, University of Cologne, Cologne, Germany
| | - Hans Clusmann
- Department of Neurosurgery, RWTH Aachen University, Aachen, Germany
| | - Toni Schneider
- Institute for Neurophysiology, University of Cologne, Cologne, Germany
| | | |
Collapse
|
12
|
Seidel RA, Claudel T, Schleser FA, Ojha NK, Westerhausen M, Nietzsche S, Sponholz C, Cuperus F, Coldewey SM, Heinemann SH, Pohnert G, Trauner M, Bauer M. Impact of higher-order heme degradation products on hepatic function and hemodynamics. J Hepatol 2017; 67:272-281. [PMID: 28412296 DOI: 10.1016/j.jhep.2017.03.037] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 03/13/2017] [Accepted: 03/20/2017] [Indexed: 01/24/2023]
Abstract
BACKGROUND & AIMS Biliverdin and bilirubin were previously considered end products of heme catabolism; now, however, there is evidence for further degradation to diverse bioactive products. Z-BOX A and Z-BOX B arise upon oxidation with unknown implications for hepatocellular function and integrity. We studied the impact of Z-BOX A and B on hepatic functions and explored their alterations in health and cholestatic conditions. METHODS Functional implications and mechanisms were investigated in rats, hepatocytic HepG2 and HepaRG cells, human immortalized hepatocytes, and isolated perfused livers. Z-BOX A and B were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in acute and acute-on-chronic liver failure and hereditary unconjugated hyperbilirubinemia. RESULTS Z-BOX A and B are found in similar amounts in humans and rodents under physiological conditions. Serum concentrations increased ∼20-fold during cholestatic liver failure in humans (p<0.001) and in hereditary deficiency of bilirubin glucuronidation in rats (p<0.001). Pharmacokinetic studies revealed shorter serum half-life of Z-BOX A compared to its regio-isomer Z-BOX B (p=0.035). While both compounds were taken up by hepatocytes, Z-BOX A was enriched ∼100-fold and excreted in bile. Despite their reported vasoconstrictive properties in the brain vasculature, BOXes did not affect portal hemodynamics. Both Z-BOX A and B showed dose-dependent cytotoxicity, affected the glutathione redox state, and differentially modulated activity of Rev-erbα and Rev-erbβ. Moreover, BOXes-triggered remodeling of the hepatocellular cytoskeleton. CONCLUSIONS Our data provide evidence that higher-order heme degradation products, namely Z-BOX A and B, impair hepatocellular integrity and might mediate intra- and extrahepatic cytotoxic effects previously attributed to hyperbilirubinemia. LAY SUMMARY Degradation of the blood pigment heme yields the bile pigment bilirubin and the oxidation products Z-BOX A and Z-BOX B. Serum concentrations of these bioactive molecules increase in jaundice and can impair liver function and integrity. Amounts of Z-BOX A and Z-BOX B that are observed during liver failure in humans have profound effects on hepatic function when added to cultured liver cells or infused into healthy rats.
Collapse
Affiliation(s)
- Raphael A Seidel
- Department of Anesthesiology and Intensive Care Medicine/Center for Sepsis Control and Care, Jena University Hospital, Germany; Institute of Inorganic and Analytical Chemistry, Bioorganic Analytics, Friedrich Schiller University Jena, Germany
| | - Thierry Claudel
- HansPopper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Austria
| | - Franziska A Schleser
- Department of Anesthesiology and Intensive Care Medicine/Center for Sepsis Control and Care, Jena University Hospital, Germany
| | - Navin K Ojha
- Center for Molecular Biomedicine, Department of Biophysics, Friedrich Schiller University Jena & Jena University Hospital, Germany
| | - Matthias Westerhausen
- Institute of Inorganic and Analytical Chemistry, Inorganic Chemistry I, Friedrich Schiller University Jena, Germany
| | | | - Christoph Sponholz
- Department of Anesthesiology and Intensive Care Medicine/Center for Sepsis Control and Care, Jena University Hospital, Germany
| | - Frans Cuperus
- HansPopper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Austria; Pediatric Gastroenterology and Hepatology, Center for Liver, Digestive, and Metabolic Diseases, University Medical Center Groningen, The Netherlands
| | - Sina M Coldewey
- Department of Anesthesiology and Intensive Care Medicine/Center for Sepsis Control and Care, Jena University Hospital, Germany
| | - Stefan H Heinemann
- Center for Molecular Biomedicine, Department of Biophysics, Friedrich Schiller University Jena & Jena University Hospital, Germany
| | - Georg Pohnert
- Institute of Inorganic and Analytical Chemistry, Bioorganic Analytics, Friedrich Schiller University Jena, Germany
| | - Michael Trauner
- HansPopper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Austria
| | - Michael Bauer
- Department of Anesthesiology and Intensive Care Medicine/Center for Sepsis Control and Care, Jena University Hospital, Germany.
| |
Collapse
|
13
|
Seidel RA, Schowtka B, Klopfleisch M, Kühl T, Weiland A, Koch A, Görls H, Imhof D, Pohnert G, Westerhausen M. Total synthesis and characterization of the bilirubin oxidation product (Z)-2-(4-ethenyl-3-methyl-5-oxo-1,5-dihydro-2H-pyrrol-2-ylidene)ethanamide (Z-BOX B). Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2014.09.108] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
14
|
Simultaneous determination of the bilirubin oxidation end products Z-BOX A and Z-BOX B in human serum using liquid chromatography coupled to tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2014; 974:83-9. [PMID: 25463201 DOI: 10.1016/j.jchromb.2014.10.027] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 10/02/2014] [Accepted: 10/21/2014] [Indexed: 02/05/2023]
Abstract
Bilirubin oxidation end products (BOXes) appear upon endogenous heme degradation and can be found in the cerebrospinal fluid after hemorrhagic stroke. BOXes are assumed to contribute to delayed cerebral vasospasm and secondary loss of brain tissue. Here, we present a validated LC-ESI-MS/MS method for the sensitive determination of the regio-isomers Z-BOX A and Z-BOX B in human serum. We found that Z-BOX A and Z-BOX B appear in serum of healthy volunteers. The sample preparation includes the addition of 5-bromonicotinamide as internal standard and protein precipitation with acetonitrile. Baseline-separation was achieved on a C-18 column with a binary solvent gradient of formic acid in water/acetonitrile at 1 mL/min within a total analysis time of 17 min. Using single reaction monitoring in the positive ion mode, the linear working ranges were 2.74-163 pg/μL (Z-BOX A) and 2.12-162.4 pg/μL (Z-BOX B) with R(2)>0.995. Intra- and inter-day precisions were <10%. The inherent analyte concentrations of Z-BOX A (14.4 ± 5.1 nM) and Z-BOX B (10.9 ± 3.1 nM) in pooled human serum were determined by standard addition. The photolability of both analytes was demonstrated. This method enables to monitor Z-BOX A and Z-BOX B as a prerequisite to systematically study the biological significance of higher order metabolites of heme degradation.
Collapse
|
15
|
Jones J, Sayre J, Chang R, Tian J, Szeder V, Gonzalez N, Jahan R, Vinuela F, Duckwiler G, Tateshima S. Cerebral vasospasm patterns following aneurysmal subarachnoid hemorrhage: an angiographic study comparing coils with clips. J Neurointerv Surg 2014; 7:803-7. [DOI: 10.1136/neurintsurg-2014-011374] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 08/30/2014] [Indexed: 11/04/2022]
|
16
|
Joerk A, Seidel RA, Walter SG, Wiegand A, Kahnes M, Klopfleisch M, Kirmse K, Pohnert G, Westerhausen M, Witte OW, Holthoff K. Impact of heme and heme degradation products on vascular diameter in mouse visual cortex. J Am Heart Assoc 2014; 3:jah3660. [PMID: 25169792 PMCID: PMC4310418 DOI: 10.1161/jaha.114.001220] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Delayed cerebral vasospasm is the most common cause of mortality and severe neurological impairment in patients who survive subarachnoid hemorrhage. Despite improvements in the field of diagnostic imaging, options for prevention and medical treatment-primarily with the calcium channel antagonist nimodipine or hemodynamic manipulations-are insufficient. Previous studies have suggested that heme and bilirubin oxidation end products, originating from degraded hemoglobin around ruptured blood vessels, are involved in the development of vasospasm by inhibiting large conductance BKC a potassium channels in vascular smooth muscle cells. In this study, we identify individual heme degradation products regulating arteriolar diameter in dependence of BKC a channel activity. METHODS AND RESULTS Using differential interference contrast video microscopy in acute brain slices, we determined diameter changes of intracerebral arterioles in mouse visual cortex. In preconstricted vessels, the specific BKC a channel blockers paxilline and iberiotoxin as well as iron-containing hemin caused vasoconstriction. In addition, the bilirubin oxidation end product Z-BOX A showed a stronger vasoconstrictive potency than its regio-isomer Z-BOX B. Importantly, Z-BOX A had the same vasoconstrictive effect, independent of its origin from oxidative degradation or chemical synthesis. Finally, in slices of Slo1-deficient knockout mice, paxilline and Z-BOX A remained ineffective in changing arteriole diameter. CONCLUSIONS We identified individual components of the oxidative bilirubin degradation that led to vasoconstriction of cerebral arterioles. The vasoconstrictive effect of Z-BOX A and Z-BOX B was mediated by BKC a channel activity that might represent a signaling pathway in the occurrence of delayed cerebral vasospasm in subarachnoid hemorrhage patients.
Collapse
Affiliation(s)
- Alexander Joerk
- Hans‐Berger Department of Neurology, University Hospital Jena, Germany (A.J., S.G.W., A.W., K.K., O.W.W., K.H.)
| | - Raphael Andreas Seidel
- Institute of Inorganic and Analytical Chemistry, Friedrich‐Schiller University, Jena, Germany (R.A.S., M.K., M.K., G.P., M.W.)
- Department of Anesthesiology and Intensive Care Medicine/Center for Sepsis Control and Care, University Hospital, Friedrich Schiller University, Jena, Germany (R.A.S.)
| | - Sebastian Gottfried Walter
- Hans‐Berger Department of Neurology, University Hospital Jena, Germany (A.J., S.G.W., A.W., K.K., O.W.W., K.H.)
| | - Anne Wiegand
- Hans‐Berger Department of Neurology, University Hospital Jena, Germany (A.J., S.G.W., A.W., K.K., O.W.W., K.H.)
| | - Marcel Kahnes
- Institute of Inorganic and Analytical Chemistry, Friedrich‐Schiller University, Jena, Germany (R.A.S., M.K., M.K., G.P., M.W.)
| | - Maurice Klopfleisch
- Institute of Inorganic and Analytical Chemistry, Friedrich‐Schiller University, Jena, Germany (R.A.S., M.K., M.K., G.P., M.W.)
| | - Knut Kirmse
- Hans‐Berger Department of Neurology, University Hospital Jena, Germany (A.J., S.G.W., A.W., K.K., O.W.W., K.H.)
| | - Georg Pohnert
- Institute of Inorganic and Analytical Chemistry, Friedrich‐Schiller University, Jena, Germany (R.A.S., M.K., M.K., G.P., M.W.)
| | - Matthias Westerhausen
- Institute of Inorganic and Analytical Chemistry, Friedrich‐Schiller University, Jena, Germany (R.A.S., M.K., M.K., G.P., M.W.)
| | - Otto Wilhelm Witte
- Hans‐Berger Department of Neurology, University Hospital Jena, Germany (A.J., S.G.W., A.W., K.K., O.W.W., K.H.)
| | - Knut Holthoff
- Hans‐Berger Department of Neurology, University Hospital Jena, Germany (A.J., S.G.W., A.W., K.K., O.W.W., K.H.)
| |
Collapse
|
17
|
Klopfleisch M, Seidel RA, Görls H, Richter H, Beckert R, Imhof W, Reiher M, Pohnert G, Westerhausen M. Total synthesis and detection of the bilirubin oxidation product (Z)-2-(3-ethenyl-4-methyl-5-oxo-1,5-dihydro-2H-pyrrol-2-ylidene)ethanamide (Z-BOX A). Org Lett 2013; 15:4608-11. [PMID: 23980716 DOI: 10.1021/ol402221b] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The selective total synthesis of the pure Z-isomer of BOX A (8a), a product of oxidative heme degradation with significant physiological impact, was achieved in four to six steps starting from 3-bromo-4-methylfuran-2,5-dione (1). Z-BOX A forms a strong hydrogen bridge framework in the crystalline state. LC-MS techniques allow identification and characterization of isomeric forms of BOX A.
Collapse
Affiliation(s)
- Maurice Klopfleisch
- Institute of Inorganic and Analytical Chemistry, Friedrich Schiller University, Humboldtstrasse 8, D-07743 Jena, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Vascular KCNQ (Kv7) potassium channels as common signaling intermediates and therapeutic targets in cerebral vasospasm. J Cardiovasc Pharmacol 2013; 61:51-62. [PMID: 23107868 DOI: 10.1097/fjc.0b013e3182771708] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Cerebral vasospasm after subarachnoid hemorrhage (SAH) is characterized by prolonged severe constriction of the basilar artery, which often leads to ischemic brain damage. Locally elevated concentrations of spasmogenic substances induce persistent depolarization of myocytes in the basilar artery, leading to continuous influx of calcium (Ca) through voltage-sensitive Ca channels and myocyte contraction. Potassium (K) channel openers may have therapeutic utility to oppose membrane depolarization, dilate the arteries, and reduce ischemia. Here, we examined the involvement of vascular Kv7 K channels in the pathogenesis of cerebral vasospasm and tested whether Kv7 channel openers are effective therapeutic agents in a rat model of SAH. Patch-clamp experiments revealed that 3 different spasmogens (serotonin, endothelin, and vasopressin) suppressed Kv7 currents and depolarized freshly isolated rat basilar artery myocytes. These effects were significantly reduced in the presence of a Kv7 channel opener, retigabine. Retigabine (10 μM) also significantly blocked L-type Ca channels, reducing peak inward currents by >50%. In the presence of a selective Kv7 channel blocker, XE991, the spasmogens did not produce additive constriction responses measured using pressure myography. Kv7 channel openers (retigabine or celecoxib) significantly attenuated basilar artery spasm in rats with experimentally induced SAH. In conclusion, we identify Kv7 channels as common targets of vasoconstrictor spasmogens and as candidates for therapeutic intervention for cerebral vasospasm.
Collapse
|
19
|
Mechanism of the modulation of BK potassium channel complexes with different auxiliary subunit compositions by the omega-3 fatty acid DHA. Proc Natl Acad Sci U S A 2013; 110:4822-7. [PMID: 23487786 DOI: 10.1073/pnas.1222003110] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Large-conductance Ca(2+)- and voltage-activated K(+) (BK) channels are well known for their functional versatility, which is bestowed in part by their rich modulatory repertoire. We recently showed that long-chain omega-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA) found in oily fish lower blood pressure by activating vascular BK channels made of Slo1+β1 subunits. Here we examined the action of DHA on BK channels with different auxiliary subunit compositions. Neuronal Slo1+β4 channels were just as well activated by DHA as vascular Slo1+β1 channels. In contrast, the stimulatory effect of DHA was much smaller in Slo1+β2, Slo1+LRRC26 (γ1), and Slo1 channels without auxiliary subunits. Mutagenesis of β1, β2, and β4 showed that the large effect of DHA in Slo1+β1 and Slo1+β4 is conferred by the presence of two residues, one in the N terminus and the other in the first transmembrane segment of the β1 and β4 subunits. Transfer of this amino acid pair from β1 or β4 to β2 introduces a large response to DHA in Slo1+β2. The presence of a pair of oppositely charged residues at the aforementioned positions in β subunits is associated with a large response to DHA. The Slo1 auxiliary subunits are expressed in a highly tissue-dependent fashion. Thus, the subunit composition-dependent stimulation by DHA demonstrates that BK channels are effectors of omega-3 fatty acids with marked tissue specificity.
Collapse
|
20
|
Omega-3 fatty acids lower blood pressure by directly activating large-conductance Ca²⁺-dependent K⁺ channels. Proc Natl Acad Sci U S A 2013; 110:4816-21. [PMID: 23487785 DOI: 10.1073/pnas.1221997110] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Long-chain polyunsaturated omega-3 fatty acids such as docosahexaenoic acid (DHA), found abundantly in oily fish, may have diverse health-promoting effects, potentially protecting the immune, nervous, and cardiovascular systems. However, the mechanisms underlying the purported health-promoting effects of DHA remain largely unclear, in part because molecular signaling pathways and effectors of DHA are only beginning to be revealed. In vascular smooth muscle cells, large-conductance Ca(2+)- and voltage-activated K(+) (BK) channels provide a critical vasodilatory influence. We report here that DHA with an EC50 of ∼500 nM rapidly and reversibly activates BK channels composed of the pore-forming Slo1 subunit and the auxiliary subunit β1, increasing currents by up to ∼20-fold. The DHA action is observed in cell-free patches and does not require voltage-sensor activation or Ca(2+) binding but involves destabilization of the closed conformation of the ion conduction gate. DHA lowers blood pressure in anesthetized wild-type but not in Slo1 knockout mice. DHA ethyl ester, contained in dietary supplements, fails to activate BK channels and antagonizes the stimulatory effect of DHA. Slo1 BK channels are thus receptors for long-chain omega-3 fatty acids, and these fatty acids--unlike their ethyl ester derivatives--activate the channels and lower blood pressure. This finding has practical implications for the use of omega-3 fatty acids as nutraceuticals for the general public and also for the critically ill receiving omega-3-enriched formulas.
Collapse
|
21
|
Pyne-Geithman GJ, Nair SG, Stamper DNC, Clark JF. Role of bilirubin oxidation products in the pathophysiology of DIND following SAH. ACTA NEUROCHIRURGICA. SUPPLEMENT 2013; 115:267-73. [PMID: 22890679 DOI: 10.1007/978-3-7091-1192-5_47] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Despite intensive research efforts, by our own team and many others, the molecules responsible for acute neurological damage following subarachnoid hemorrhage (SAH) and contributing to delayed ischemic neurological deficit (DIND) have not yet been elucidated. While there are a number of candidate mechanisms, including nitric oxide (NO) scavenging, endothelin-1, protein kinase C (PKC) activation, and rho kinase activation, to name but a few, that have been investigated using animal models and human trials, we are, it seems, no closer to discovering the true nature of this complex and enigmatic pathology. Efforts in our laboratory have focused on the chemical milieu present in hemorrhagic cerebrospinal fluid (CSF) following SAH and the interaction of the environment with the molecules generated by SAH and subsequent events, including NO scavenging, immune response, and clot breakdown. We have identified and characterized a group of molecules formed by the oxidative degradation of bilirubin (a clot breakdown product) and known as BOXes (bilirubin oxidation products). We present a synopsis of the characterization of BOXes as found in human SAH patients' CSF and the multiple signaling pathways by which BOXes act. In summary, BOXes are likely to play an essential role in the etiology of acute brain injury following SAH, as well as DIND.
Collapse
|
22
|
Systematic interaction analysis of human lipocalin-type prostaglandin D synthase with small lipophilic ligands. Biochem J 2012; 446:279-89. [DOI: 10.1042/bj20120324] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
L-PGDS [lipocalin-type PG (prostaglandin) D synthase] is a multi-functional protein, acting as a PGD2-producing enzyme and a lipid-transporter. In the present study, we focus on the function of L-PGDS as an extracellular transporter for small lipophilic molecules. We characterize the binding mechanism of human L-PGDS for the molecules, especially binding affinity stoichiometry and driving force, using tryptophan fluorescence quenching, ICD (induced circular dichroism) and ITC (isothermal titration calorimetry). The tryptophan fluorescence quenching measurements revealed that haem metabolites such as haemin, biliverdin and bilirubin bind to L-PGDS with significantly higher affinities than the other small lipophilic ligands examined, showing dissociation constant (Kd) values from 17.0 to 20.9 nM. We focused particularly on the extra-specificities of haem metabolites and L-PGDS. The ITC and ICD data revealed that two molecules of the haem metabolites bind to L-PGDS with high and low affinities, showing Kd values from 2.8 to 18.1 nM and from 0.209 to 1.63 μM respectively. The thermodynamic parameters for the interactions revealed that the contributions of enthalpy and entropy change were considerably different for each haem metabolite even when the Gibbs energy change was the same. Thus we believe that the binding energy of haem metabolites to L-PGDS is optimized by balancing enthalpy and entropy change.
Collapse
|