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Seong M, Oh Y, Park HJ, Choi WS, Kim JG. Use of Hypoxic Respiratory Challenge for Differentiating Alzheimer's Disease and Wild-Type Mice Non-Invasively: A Diffuse Optical Spectroscopy Study. BIOSENSORS 2022; 12:1019. [PMID: 36421136 PMCID: PMC9688818 DOI: 10.3390/bios12111019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/12/2022] [Accepted: 11/13/2022] [Indexed: 06/16/2023]
Abstract
Alzheimer's disease is one of the most critical brain diseases. The prevalence of the disease keeps rising due to increasing life spans. This study aims to examine the use of hemodynamic signals during hypoxic respiratory challenge for the differentiation of Alzheimer's disease (AD) and wild-type (WT) mice. Diffuse optical spectroscopy, an optical system that can non-invasively monitor transient changes in deoxygenated (ΔRHb) and oxygenated (ΔOHb) hemoglobin concentrations, was used to monitor hemodynamic reactivity during hypoxic respiratory challenges in an animal model. From the acquired signals, 13 hemodynamic features were extracted from each of ΔRHb and -ΔOHb (26 features total) for more in-depth analyses of the differences between AD and WT. The hemodynamic features were statistically analyzed and tested to explore the possibility of using machine learning (ML) to differentiate AD and WT. Among the twenty-six features, two features of ΔRHb and one feature of -ΔOHb showed statistically significant differences between AD and WT. Among ML techniques, a naive Bayes algorithm achieved the best accuracy of 84.3% when whole hemodynamic features were used for differentiation. While further works are required to improve the approach, the suggested approach has the potential to be an alternative method for the differentiation of AD and WT.
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Affiliation(s)
- Myeongsu Seong
- School of Information Science and Technology, Nantong University, Nantong 226019, China
- Research Center for Intelligent Information Technology, Nantong University, Nantong 226019, China
| | - Yoonho Oh
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Hyung Joon Park
- School of Biological Sciences and Technology, College of Natural Sciences, College of Medicine, Chonnam National University, Gwangju 61186, Republic of Korea
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Won-Seok Choi
- School of Biological Sciences and Technology, College of Natural Sciences, College of Medicine, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jae Gwan Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
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Lee J, Rockwood G, Logue B, Manandhar E, Petrikovics I, Han C, Bebarta V, Mahon SB, Burney T, Brenner M. Monitoring Dose Response of Cyanide Antidote Dimethyl Trisulfide in Rabbits Using Diffuse Optical Spectroscopy. J Med Toxicol 2018; 14:295-305. [PMID: 30094773 DOI: 10.1007/s13181-018-0680-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 07/17/2018] [Accepted: 07/23/2018] [Indexed: 01/22/2023] Open
Abstract
INTRODUCTION Cyanide (CN) poisoning is a serious chemical threat from accidental or intentional exposures. Current CN exposure treatments, including direct binding agents, methemoglobin donors, and sulfur donors, have several limitations. Dimethyl trisulfide (DMTS) is capable of reacting with CN to form the less toxic thiocyanate with high efficiency, even without the sulfurtransferase rhodanese. We investigated a soluble DMTS formulation with the potential to provide a continuous supply of substrate for CN detoxification which could be delivered via intramuscular (IM) injection in a mass casualty situation. We also used non-invasive technology, diffuse optical spectroscopy (DOS), to monitor physiologic changes associated with CN exposure and reversal. METHODS Thirty-six New Zealand white rabbits were infused with a lethal dose of sodium cyanide solution (20 mg/60 ml normal saline). Animals were divided into three groups and treated with saline, low dose (20 mg), or high dose (150 mg) of DMTS intramuscularly. DOS continuously assessed changes in tissue hemoglobin concentrations and cytochrome c oxidase redox state status throughout the experiment. RESULTS IM injection of DMTS increased the survival in lethal CN poisoning. DOS demonstrated that high-dose DMTS (150 mg) reversed the effects of CN exposure on cytochrome c oxidase, while low dose (20 mg) did not fully reverse effects, even in surviving animals. CONCLUSIONS This study demonstrated potential efficacy for the novel approach of supplying substrate for non-rhodanese mediated sulfur transferase pathways for CN detoxification via intramuscular injection in a moderate size animal model and showed that DOS was useful for optimizing the DMTS treatment.
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Affiliation(s)
- Jangwoen Lee
- Beckman Laser Institute, University of California, 1002 Health Sciences Rd. East, Irvine, CA, 92612, USA.
| | - Gary Rockwood
- Analytical Toxicology Division, US Army Medical Research Institute of Chemical Defense, 2900 Rickets Point Road, Aberdeen Proving Ground, Aberdeen, MD, 21010, USA
| | - Brian Logue
- Department of Chemistry and Biochemistry, South Dakota University, Brookings, SD, 57007, USA
| | - Erica Manandhar
- Department of Chemistry and Biochemistry, South Dakota University, Brookings, SD, 57007, USA
| | - Ilona Petrikovics
- Department of Chemistry, Sam Houston State University, Huntsville, TX, 77341, USA
| | - Changhoon Han
- Department of Internal Medicine, National Health Insurance Service Ilsan Hospital, Goyang-si, Geonggi-do, 10444, South Korea
| | - Vik Bebarta
- Department of Emergency Medicine, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - Sari B Mahon
- Beckman Laser Institute, University of California, 1002 Health Sciences Rd. East, Irvine, CA, 92612, USA
| | - Tanya Burney
- Beckman Laser Institute, University of California, 1002 Health Sciences Rd. East, Irvine, CA, 92612, USA
| | - Matthew Brenner
- Beckman Laser Institute, University of California, 1002 Health Sciences Rd. East, Irvine, CA, 92612, USA
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of California, Irvine, CA, 92868, USA
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Brenner M, Azer SM, Oh KJ, Han CH, Lee J, Mahon SB, Du X, Mukai D, Burney T, Saidian M, Chan A, Straker DI, Bebarta VS, Boss GR. Oral Glycine and Sodium Thiosulfate for Lethal Cyanide Ingestion. ACTA ACUST UNITED AC 2017; 7. [PMID: 28868209 PMCID: PMC5578424 DOI: 10.4172/2167-7972.1000355] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Objective Accidental or intentional cyanide ingestion is an-ever present danger. Rapidly acting, safe, inexpensive oral cyanide antidotes are needed that can neutralize large gastrointestinal cyanide reservoirs. Since humans cannot be exposed to cyanide experimentally, we studied oral cyanide poisoning in rabbits, testing oral sodium thiosulfate with and without gastric alkalization. Setting University research laboratory. Subjects New Zealand white rabbits. Interventions Seven animal groups studied; Groups 1–5 received high dose oral NaCN (50 mg, >LD100) and were treated immediately with oral (via nasogastric tube): 1) saline, 2) glycine, 3) sodium thiosulfate or 4) sodium thiosulfate and glycine, or 5) after 2 min with intramuscular injection of sodium nitrite and sodium thiosulfate plus oral sodium thiosulfate and glycine. Groups 6–7 received moderate dose oral NaCN (25 mg, LD70) and delayed intramuscular 6) saline or 7) sodium nitrite-sodium thiosulfate. Measurements and Main Results All animals in the high dose NaCN group receiving oral saline or glycine died very rapidly, with a trend towards delayed death in glycine-treated animals; saline versus glycine-treated animals died at 10.3+3.9 and 14.6+5.9 min, respectively (p=0.13). In contrast, all sodium thiosulfate-treated high dose cyanide animals survived (p<0.01), with more rapid recovery in animals receiving both thiosulfate and glycine, compared to thiosulfate alone (p<0.03). Delayed intramuscular treatment alone in the moderate cyanide dose animals increased survival over control animals from 30% to 71%. Delayed treatment in high dose cyanide animals was not as effective as immediate treatment, but did increase survival time and rescued 29% of animals (p<0.01 versus cyanide alone). Conclusions Oral sodium thiosulfate with gastric alkalization rescued animals from lethal doses of ingested cyanide. The combination of oral glycine and sodium thiosulfate may have potential for treating high dose acute cyanide ingestion and merits further investigation. The combination of systemic and oral therapy may provide further options.
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Affiliation(s)
- Matthew Brenner
- Beckman Laser Institute, University of California, Irvine, California, USA.,Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of California, Irvine, California, USA
| | - Sarah M Azer
- Beckman Laser Institute, University of California, Irvine, California, USA
| | - Kyung-Jin Oh
- Department of Urology, Chonnam National University Medical School, South Korea
| | - Chang Hoon Han
- Department of Internal Medicine, National Health Insurance Service Ilsan Hospital, Goyang-si, Geonggi-do, South Korea
| | - Jangwoen Lee
- Beckman Laser Institute, University of California, Irvine, California, USA
| | - Sari B Mahon
- Beckman Laser Institute, University of California, Irvine, California, USA
| | - Xiaohua Du
- Pulmonary Department, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - David Mukai
- Beckman Laser Institute, University of California, Irvine, California, USA
| | - Tanya Burney
- Beckman Laser Institute, University of California, Irvine, California, USA
| | - Mayer Saidian
- Beckman Laser Institute, University of California, Irvine, California, USA.,The Institute for Drug Research, School of Pharmacy, Hebrew University of Jerusalem, Jerusalem Israel
| | - Adriano Chan
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Derek I Straker
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Vikhyat S Bebarta
- Department of Emergency Medicine, University of Colorado School of Medicine, Aurora, CO, USA
| | - Gerry R Boss
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
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Bebarta VS, Brittain M, Chan A, Garrett N, Yoon D, Burney T, Mukai D, Babin M, Pilz RB, Mahon SB, Brenner M, Boss GR. Sodium Nitrite and Sodium Thiosulfate Are Effective Against Acute Cyanide Poisoning When Administered by Intramuscular Injection. Ann Emerg Med 2016; 69:718-725.e4. [PMID: 28041825 DOI: 10.1016/j.annemergmed.2016.09.034] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 09/16/2016] [Accepted: 09/22/2016] [Indexed: 11/29/2022]
Abstract
STUDY OBJECTIVE The 2 antidotes for acute cyanide poisoning in the United States must be administered by intravenous injection. In the out-of-hospital setting, intravenous injection is not practical, particularly for mass casualties, and intramuscular injection would be preferred. The purpose of this study is to determine whether sodium nitrite and sodium thiosulfate are effective cyanide antidotes when administered by intramuscular injection. METHODS We used a randomized, nonblinded, parallel-group study design in 3 mammalian models: cyanide gas inhalation in mice, with treatment postexposure; intravenous sodium cyanide infusion in rabbits, with severe hypotension as the trigger for treatment; and intravenous potassium cyanide infusion in pigs, with apnea as the trigger for treatment. The drugs were administered by intramuscular injection, and all 3 models were lethal in the absence of therapy. RESULTS We found that sodium nitrite and sodium thiosulfate individually rescued 100% of the mice, and that the combination of the 2 drugs rescued 73% of the rabbits and 80% of the pigs. In all 3 species, survival in treated animals was significantly better than in control animals (log rank test, P<.05). In the pigs, the drugs attenuated an increase in the plasma lactate concentration within 5 minutes postantidote injection (difference: plasma lactate, saline solution-treated versus nitrite- or thiosulfate-treated 1.76 [95% confidence interval 1.25 to 2.27]). CONCLUSION We conclude that sodium nitrite and sodium thiosulfate administered by intramuscular injection are effective against severe cyanide poisoning in 3 clinically relevant animal models of out-of-hospital emergency care.
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Affiliation(s)
- Vikhyat S Bebarta
- Department of Emergency Medicine, University of Colorado, School of Medicine, Aurora, CO
| | | | - Adriano Chan
- Department of Medicine, University of California, San Diego, La Jolla, CA
| | - Norma Garrett
- Medical Toxicology and the Department of Emergency Medicine, San Antonio Military Medical Center/59 MDW, San Antonio, TX
| | - David Yoon
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, Irvine, CA
| | - Tanya Burney
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, Irvine, CA
| | - David Mukai
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, Irvine, CA
| | | | - Renate B Pilz
- Department of Medicine, University of California, San Diego, La Jolla, CA
| | - Sari B Mahon
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, Irvine, CA
| | - Matthew Brenner
- Beckman Laser Institute and Medical Clinic, University of California, Irvine, Irvine, CA
| | - Gerry R Boss
- Department of Medicine, University of California, San Diego, La Jolla, CA
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Choi DH, Shin TJ, Kim S, Bae J, Cho D, Ham J, Park JY, Kim HI, Jeong S, Lee B, Kim JG. Monitoring cerebral oxygenation and local field potential with a variation of isoflurane concentration in a rat model. BIOMEDICAL OPTICS EXPRESS 2016; 7:4114-4124. [PMID: 27867719 PMCID: PMC5102553 DOI: 10.1364/boe.7.004114] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/25/2016] [Accepted: 09/09/2016] [Indexed: 06/06/2023]
Abstract
We aimed to investigate experimentally how anesthetic levels affect cerebral metabolism measured by near-infrared spectroscopy (NIRS) and to identify a robust marker among NIRS parameters to discriminate various stages of anesthetic depth in rats under isoflurane anesthesia. In order to record the hemodynamic changes and local field potential (LFP) in the brain, fiber-optic cannulae and custom-made microelectrodes were implanted in the frontal cortex of the skull. The NIRS and LFP signals were continuously monitored before, during and after isoflurane anesthesia. As isoflurane concentration is reduced, the level of oxyhemoglobin and total hemoglobin concentrations of the frontal cortex decreased gradually, while deoxyhemoglobin increased. The reflectance ratio between 730nm and 850nm and burst suppression ratio (BSR) correspond similarly with the change of oxyhemoglobin during the variation of isoflurane concentration. These results suggest that NIRS signals in addition to EEG may provide a possibility of developing a new anesthetic depth index.
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Affiliation(s)
- Dong-Hyuk Choi
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea; These authors contributed equally to this study
| | - Teo Jeon Shin
- Department of Pediatric Dentistry, School of Dentistry, Seoul National University, Seoul 03080, South Korea; These authors contributed equally to this study
| | - Seonghyun Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Jayyoung Bae
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Dongrae Cho
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Jinsil Ham
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Ji-Young Park
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Hyoung-Ihl Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea
| | - Seongwook Jeong
- Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju 61469, South Korea
| | - Boreom Lee
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea;
| | - Jae Gwan Kim
- Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, South Korea;
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The Vitamin B 12 Analog Cobinamide Is an Effective Antidote for Oral Cyanide Poisoning. J Med Toxicol 2016; 12:370-379. [PMID: 27631586 DOI: 10.1007/s13181-016-0566-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 05/31/2016] [Accepted: 06/14/2016] [Indexed: 10/21/2022] Open
Abstract
INTRODUCTION Cyanide is a major chemical threat, and cyanide ingestion carries a higher risk for a supra-lethal dose exposure compared to inhalation but provides an opportunity for effective treatment due to a longer treatment window and a gastrointestinal cyanide reservoir that could be neutralized prior to systemic absorption. We hypothesized that orally administered cobinamide may function as a high-binding affinity scavenger and that gastric alkalinization would reduce cyanide absorption and concurrently increase cobinamide binding, further enhancing antidote effectiveness. METHODS Thirty New Zealand white rabbits were divided into five groups and were given a lethal dose of oral cyanide poisoning (50 mg). The survival time of animals was monitored with oral cyanide alone, oral cyanide with gastric alkalinization with oral sodium bicarbonate buffer (500 mg), and in combination with either aquohydroxocobinamide or dinitrocobinamide (250 mM). Red blood cell cyanide concentration, plasma cobinamide, and thiocyanate concentrations were measured from blood samples. RESULTS In cyanide ingested animals, oral sodium bicarbonate alone significantly prolonged survival time to 20.3 ± 8.6 min compared to 10.5 ± 4.3 min in saline-treated controls, but did not lead to overall survival. Aquohydroxocobinamide and dinitrocobinamide increased survival time to 64 ± 41 (p < 0.05) and 75 ± 16.4 min (p < 0.001), respectively. Compared to aquohydroxocobinamide, dinitrocobinamide showed greater systemic absorption and reduced blood pressure. Dinitrocobinamide also markedly increased the red blood cell cyanide concentration. Under all conditions, the plasma thiocyanate concentration gradually increased with time. CONCLUSION This study demonstrates a promising new approach to treat high-dose cyanide ingestion, with gastric alkalinization alone and in combination with oral cobinamide for treating a supra-lethal dose of orally administered cyanide in rabbits.
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Chan A, Jiang J, Fridman A, Guo LT, Shelton GD, Liu MT, Green C, Haushalter KJ, Patel HH, Lee J, Yoon D, Burney T, Mukai D, Mahon SB, Brenner M, Pilz RB, Boss GR. Nitrocobinamide, a new cyanide antidote that can be administered by intramuscular injection. J Med Chem 2015; 58:1750-9. [PMID: 25650735 DOI: 10.1021/jm501565k] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Currently available cyanide antidotes must be given by intravenous injection over 5-10 min, making them ill-suited for treating many people in the field, as could occur in a major fire, an industrial accident, or a terrorist attack. These scenarios call for a drug that can be given quickly, e.g., by intramuscular injection. We have shown that aquohydroxocobinamide is a potent cyanide antidote in animal models of cyanide poisoning, but it is unstable in solution and poorly absorbed after intramuscular injection. Here we show that adding sodium nitrite to cobinamide yields a stable derivative (referred to as nitrocobinamide) that rescues cyanide-poisoned mice and rabbits when given by intramuscular injection. We also show that the efficacy of nitrocobinamide is markedly enhanced by coadministering sodium thiosulfate (reducing the total injected volume), and we calculate that ∼1.4 mL each of nitrocobinamide and sodium thiosulfate should rescue a human from a lethal cyanide exposure.
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Affiliation(s)
- Adriano Chan
- Departments of †Medicine, ‡Pathology, §Chemistry and Biochemistry, and ∥Anesthesiology, University of California-San Diego , La Jolla, California 92093-0652, United States
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Szabó A, Áprily S, Kacsala L, Vajda T, Rekedtné-Fekete E, Bónai A, Toldi M, Romvári R. Investigation of the Background of Greening of Fatty Goose Liver (Foie Gras) during Prolonged Frozen Storage under Vacuum. J FOOD QUALITY 2014. [DOI: 10.1111/jfq.12087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- András Szabó
- Faculty of Agricultural and Environmental Sciences; Kaposvár University; Guba S. u. 40. Kaposvár 7400 Hungary
| | - Szilvia Áprily
- Faculty of Agricultural and Environmental Sciences; Kaposvár University; Guba S. u. 40. Kaposvár 7400 Hungary
| | - László Kacsala
- Faculty of Agricultural and Environmental Sciences; Kaposvár University; Guba S. u. 40. Kaposvár 7400 Hungary
| | - Tamás Vajda
- Integrál Food Industrial and Trading Corp.; Kiskunfélegyháza Hungary
| | | | - András Bónai
- “MTA-KE Mycotoxins in the Food Chain Research Group”, Hungarian Academy of Sciences; Kaposvár University; Kaposvár Hungary
| | - Mária Toldi
- Faculty of Agricultural and Environmental Sciences; Kaposvár University; Guba S. u. 40. Kaposvár 7400 Hungary
| | - Róbert Romvári
- Faculty of Agricultural and Environmental Sciences; Kaposvár University; Guba S. u. 40. Kaposvár 7400 Hungary
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Brenner M, Benavides S, Mahon SB, Lee J, Yoon D, Mukai D, Viseroi M, Chan A, Jiang J, Narula N, Azer SM, Alexander C, Boss GR. The vitamin B12 analog cobinamide is an effective hydrogen sulfide antidote in a lethal rabbit model. Clin Toxicol (Phila) 2014; 52:490-7. [PMID: 24716792 DOI: 10.3109/15563650.2014.904045] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND AND PURPOSE Hydrogen sulfide (H2S) is a highly toxic gas for which no effective antidotes exist. It acts, at least in part, by binding to cytochrome c oxidase, causing cellular asphyxiation and anoxia. We investigated the effects of three different ligand forms of cobinamide, a vitamin B12 analog, to reverse sulfide (NaHS) toxicity. METHODS New Zealand white rabbits received a continuous intravenous (IV) infusion of NaHS (3 mg/min) until expiration or a maximum 270 mg dose. Animals received six different treatments, administered at the time when they developed signs of severe toxicity: Group 1-saline (placebo group, N = 9); Group 2--IV hydroxocobalamin (N = 7); Group 3--IV aquohydroxocobinamide (N = 6); Group 4--IV sulfitocobinamide (N = 6); Group 5--intramuscular (IM) sulfitocobinamide (N = 6); and Group 6-IM dinitrocobinamide (N = 8). Blood was sampled intermittently, and systemic blood pressure and deoxygenated and oxygenated hemoglobin were measured continuously in peripheral muscle and over the brain region; the latter were measured by diffuse optical spectroscopy (DOS) and continuous wave near infrared spectroscopy (CWNIRS). RESULTS Compared with the saline controls, all cobinamide derivatives significantly increased survival time and the amount of NaHS that was tolerated. Aquohydroxocobinamide was most effective (261.5 ± 2.4 mg NaHS tolerated vs. 93.8 ± 6.2 mg in controls, p < 0.0001). Dinitrocobinamide was more effective than sulfitocobinamide. Hydroxocobalamin was not significantly more effective than the saline control. CONCLUSIONS Cobinamide is an effective agent for inhibiting lethal sulfide exposure in this rabbit model. Further studies are needed to determine the optimal dose and form of cobinamide and route of administration.
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Affiliation(s)
- M Brenner
- Beckman Laser Institute, University of California , Irvine, CA , USA
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