1
|
Selli AL, Kuzmiszyn AK, Smaglyukova N, Kondratiev TV, Fuskevåg OM, Lyså RA, Ravna AW, Tveita T, Sager G, Dietrichs ES. Treatment of Cardiovascular Dysfunction With PDE5-Inhibitors - Temperature Dependent Effects on Transport and Metabolism of cAMP and cGMP. Front Physiol 2021; 12:695779. [PMID: 34393818 PMCID: PMC8361756 DOI: 10.3389/fphys.2021.695779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 07/09/2021] [Indexed: 01/24/2023] Open
Abstract
Introduction Cardiovascular dysfunction is a potentially lethal complication of hypothermia. Due to a knowledge gap, pharmacological interventions are not recommended at core temperatures below 30°C. Yet, further cooling is induced in surgical procedures and survival of accidental hypothermia is reported after rewarming from below 15°C, advocating a need for evidence-based treatment guidelines. In vivo studies have proposed vasodilation and afterload reduction through arteriole smooth muscle cGMP-elevation as a favorable strategy to prevent cardiovascular dysfunction in hypothermia. Further development of treatment guidelines demand information about temperature-dependent changes in pharmacological effects of clinically relevant vasodilators. Materials and Methods Human phosphodiesterase-enzymes and inverted erythrocytes were utilized to evaluate how vasodilators sildenafil and vardenafil affected cellular efflux and enzymatic breakdown of cAMP and cGMP, at 37°C, 34°C, 32°C, 28°C, 24°C, and 20°C. The ability of both drugs to reach their cytosolic site of action was assessed at the same temperatures. IC50- and Ki-values were calculated from dose–response curves at all temperatures, to evaluate temperature-dependent effects of both drugs. Results Both drugs were able to reach the intracellular space at all hypothermic temperatures, with no reduction compared to normothermia. Sildenafil IC50 and Ki-values increased during hypothermia for enzymatic breakdown of both cAMP (IC50: 122 ± 18.9 μM at 37°C vs. 269 ± 14.7 μM at 20°C, p < 0.05) and cGMP (IC50: 0.009 ± 0.000 μM at 37°C vs. 0.024 ± 0.004 μM at 32°C, p < 0.05), while no significant changes were detected for vardenafil. Neither of the drugs showed significant hypothermia-induced changes in IC50 and Ki–values for inhibition of cellular cAMP and cGMP efflux. Conclusion Sildenafil and particularly vardenafil were ableto inhibit elimination of cGMP down to 20°C. As the cellular effects of these drugs can cause afterload reduction, they show potential in treating cardiovascular dysfunction during hypothermia. As in normothermia, both drugs showed higher selectivity for inhibition of cGMP-elimination than cAMP-elimination at low core temperatures, indicating that risk for cardiotoxic side effects is not increased by hypothermia.
Collapse
Affiliation(s)
- Anders L Selli
- Experimental and Clinical Pharmacology, Department of Medical Biology, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Adrina K Kuzmiszyn
- Experimental and Clinical Pharmacology, Department of Medical Biology, UiT - The Arctic University of Norway, Tromsø, Norway.,Division of Surgical Medicine and Intensive Care, University Hospital of North Norway, Tromsø, Norway
| | - Natalia Smaglyukova
- Experimental and Clinical Pharmacology, Department of Medical Biology, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Timofei V Kondratiev
- Anesthesia and Critical Care Research Group, Department of Clinical Medicine, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Ole-Martin Fuskevåg
- Department of Laboratory Medicine, Division of Diagnostic Services, University Hospital of North Norway, Tromsø, Norway
| | - Roy A Lyså
- Experimental and Clinical Pharmacology, Department of Medical Biology, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Aina W Ravna
- Experimental and Clinical Pharmacology, Department of Medical Biology, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Torkjel Tveita
- Division of Surgical Medicine and Intensive Care, University Hospital of North Norway, Tromsø, Norway.,Anesthesia and Critical Care Research Group, Department of Clinical Medicine, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Georg Sager
- Experimental and Clinical Pharmacology, Department of Medical Biology, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Erik S Dietrichs
- Experimental and Clinical Pharmacology, Department of Medical Biology, UiT - The Arctic University of Norway, Tromsø, Norway.,Center for Psychopharmacology, Diakonhjemmet Hospital, Oslo, Norway
| |
Collapse
|
2
|
Lin KH, Chang RL, Tamilselvi S, Paul CR, Pai PY, Day CH, Wu HC, PadmaViswanadha V, Kuo WW, Huang CY. Reperfusion using lactate Ringer's mixture partially eliminates IGF II receptor involved cardiac damage caused by hemorrhagic shock in diabetic rats. Biotech Histochem 2020; 95:163-170. [PMID: 32053010 DOI: 10.1080/10520295.2019.1651397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Diabetes is a metabolic disorder that damages many organs. We investigated the effects of reperfusion using lactate Ringer's solution (LR) in a diabetic animal model. Eight-week-old rats were divided into groups: control, hemorrhagic shock induced (HS), diabetes mellitus (DM), DM plus HS (DM + HS) and DM rats that received LR after HS (DM + HS + LR). HS was induced by withdrawing blood from the femoral artery and arterial pressure was maintained at 40 mm Hg for 1 h. Animals were perfused with either withdrawn blood or LR. Rats were sacrificed and hearts were collected from all groups. Histopathological studies were performed using left ventricles and western blotting analysis was performed using protein extracted from the left ventricle. Using the TUNEL assay, we found more apoptotic cells in the DM + HS group compared to the control group, whereas in animals resuscitated with LR, the number of apoptotic cells was reduced. Western blotting showed a significant reduction in apoptotic markers, cyt c, cas 9 and cas 3, and increased survival markers, pPI3K and pAKT, in the DM + HS + LR group. Reperfusion with LR may have therapeutic effects on trauma induced HS by blocking the IGF II R facilitated apoptosis pathway in diabetic rats.
Collapse
Affiliation(s)
- K-H Lin
- College of Medicine, China Medical University, Taichung, Taiwan.,Department of Emergency Medicine, China Medical University Hospital, Taichung, Taiwan
| | - R-L Chang
- School of Post-Baccalaureate Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan
| | - S Tamilselvi
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
| | - C R Paul
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
| | - P-Y Pai
- Division of Cardiology, China Medical University Hospital, Taichung, Taiwan
| | - C H Day
- Department of Nursing, MeiHo University, Pingtung, Taiwan
| | - H-C Wu
- School of medicine, China Medical University, Taichung, Taiwan
| | - V PadmaViswanadha
- Department of Biotechnology, Bharathiar University, Coimbatore, India
| | - W-W Kuo
- Department of Biological Science and Technology, China Medical University, Taichung, Taiwan
| | - C-Y Huang
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan.,Cardiovascular Research Center, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Tzu Chi University of Science and Technology, Hualien, Taiwan.,Department of Biotechnology, Asia University, Taichung, Taiwan
| |
Collapse
|
3
|
Crombez T, Hachimi-Idrissi S. The influence of targeted temperature management on the pharmacokinetics of drugs administered during and after cardiac arrest: a systematic review. Acta Clin Belg 2017; 72:116-122. [PMID: 28220713 DOI: 10.1080/17843286.2017.1291782] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
OBJECTIVE Pharmacokinetic parameters of drugs are widely investigated under normothermic conditions and normal hemodynamic parameters. The European Resuscitation Council recommends the use of targeted temperature management (TTM) with a target temperature of 34 °C in cardiac arrest (CA) patients. The aim of this literature review is to investigate the influence of CA combined with TTM on the pharmacokinetics of drugs. Results of preclinical and clinical studies are compared with each other. Only the most important drugs, administered during CA in emergency setting, were studied. METHODS A literature search was conducted within PubMed and Google Scholar. The search terms included 'therapeutic hypothermia', 'TTM', 'drug metabolism', 'pharmacokinetics during hypothermia', 'cardiac arrest/etiology'. In Pubmed, MeSH-terms were also included: 'myocardial infarction/therapy', 'heart arrest/complications' and 'hypothermia'. To search for preclinical studies: the search terms 'pigs' and 'swine' were used. After the primary shift of relevant findings, further articles were found through references of these (snowballing method), as well as through related articles as suggested by the databases. RESULTS Due to the reduced cardiac output during TTM, most of the distribution volume ([Formula: see text]) of drugs included in this literature study is decreased. Only the [Formula: see text] of chlorzoxazone in CA rats and midazolam in non-CA patients are significantly increased during respectively deep and mild hypothermia. The renal, hepatic and biliary clearance of drugs administered during CA/TTM/hypothermia are decreased. DISCUSSION The combination of a decreased [Formula: see text] and a decrease in the metabolization/excretion of drugs during CA/TTM result in higher plasma concentrations compared to the plasma concentrations during CA without TTM.
Collapse
Affiliation(s)
- Tessa Crombez
- Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - Said Hachimi-Idrissi
- Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
- Department of Emergency Medicine, Ghent University Hospital, Ghent, Belgium
| |
Collapse
|
4
|
Witcher R, Dzierba AL, Kim C, Smithburger PL, Kane-Gill SL. Adverse drug reactions in therapeutic hypothermia after cardiac arrest. Ther Adv Drug Saf 2016; 8:101-111. [PMID: 28382198 DOI: 10.1177/2042098616679813] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Therapeutic hypothermia (TH) improves survival and neurologic function in comatose survivors of cardiac arrest. Many medications used to support TH have altered pharmacokinetics and pharmacodynamics during this treatment. It is unknown if or at what frequency the medications used during TH cause adverse drug reactions (ADRs). METHODS A retrospective chart review was conducted for patients admitted to an intensive care unit (ICU) after cardiac arrest and treated with TH from January 2009 to June 2012 at two urban, university-affiliated, tertiary-care medical centres. Medications commonly used during TH were screened for association with significant ADRs (grade 3 or greater per Common Terminology Criteria for Adverse Events) using three published ADR detection instruments. RESULTS A total of 229 patients were included, the majority being males with median age of 62 presenting with an out-of-hospital cardiac arrest in pulseless electrical activity or asystole. The most common comorbidities were hypertension, coronary artery disease, and diabetes mellitus. There were 670 possible ADRs and 69 probable ADRs identified. Of the 670 possible ADRs, propofol, fentanyl, and acetaminophen were the most common drugs associated with ADRs. Whereas fentanyl, insulin, and propofol were the most common drugs associated with a probable ADR. Patients were managed with TH for a median of 22 hours, with 38% of patients surviving to hospital discharge. CONCLUSIONS Patients undergoing TH after cardiac arrest frequently experience possible adverse reactions associated with medications and the corresponding laboratory abnormalities are significant. There is a need for judicious use and close monitoring of drugs in the setting of TH until recommendations for dose adjustments are available to help prevent ADRs.
Collapse
Affiliation(s)
- Robert Witcher
- New York University Langone Medical Centre, New York, NY, USA
| | | | - Catherine Kim
- University of Pittsburgh, School of Pharmacy, Pittsburgh, PA, USA Department of Pharmacy, University of Pittsburgh Medical Centre, Pittsburgh, PA, USA
| | - Pamela L Smithburger
- University of Pittsburgh, School of Pharmacy, Pittsburgh, PA, USA Department of Pharmacy, University of Pittsburgh Medical Centre, Pittsburgh, PA, USA
| | - Sandra L Kane-Gill
- School of Pharmacy, University of Pittsburgh, 918 Salk Hall, 3501 Terrace Street, Pittsburgh, PA 15261, USA
| |
Collapse
|
5
|
Gao N, Fang Y, Qi B, Jia LJ, Jin H, Qiao HL. Pharmacokinetic changes of unbound theophylline are due to plasma protein binding displacement and CYP1A2 activity inhibition by baicalin in rats. JOURNAL OF ETHNOPHARMACOLOGY 2013; 150:477-484. [PMID: 24076258 DOI: 10.1016/j.jep.2013.08.062] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2012] [Revised: 07/23/2013] [Accepted: 08/29/2013] [Indexed: 06/02/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Baicalin is one of the major bioactive constituents of Scutellariae Radix, the root of Scutellariae baicalensis Georgi and possesses a wide variety of pharmacological properties. AIM OF THE STUDY To elucidate the effect of baicalin on the pharmacokinetics of theophylline in rats, focusing on plasma protein binding displacement and inhibition effect on CYP1A2 in vivo and in vitro. MATERIALS AND METHODS The study was a randomized, three-period crossover design. Nine rats were given saline (control) or 450 mg/kg baicalin (dosage regimen A or B). Dosage regimen A was administered once at 0 h. Dosage regimen B was divided into three dosages (225,112.5, 112.5 mg/kg) and was given at 0, 2 and 4 h, respectively. Then theophylline (5 mg/kg, i.v.) was administered immediately. The effect of baicalin on CYP1A2 activity was determined by metabolism of phenacetin in vitro and plasma protein binding of theophylline was determined by ultrafiltration. RESULTS C(max) decreased from (12.4 ± 1.6) to (8.7 ± 0.9) and (8.6 ± 2.0) mg/L, T(1/2) increased by 116 and 96%, V(d) increased by 51 and 49% for total theophylline in rats treated with dosage regimen A and B of baicalin, respectively. Cmax was significantly increased, V(d) decreased by 43 and 29% for unbound theophylline in rats treated with dosage regimen A and B of baicalin, respectively (P < 0.01). T(1/2) of unbound theophylline increased by 104% only in rats treated with dosage regimen B. No significant effects on the CL and AUC of both total and unbound theophylline were observed in the rats treated with dosage regimen A, but the CL decreased and AUC increased for total theophylline and CL decreased for unbound theophylline in the group treated with dosage regimen B (P < 0.05). Correlation analysis showed that the mean unbound theophylline (%) and mean baicalin concentration was in good correlation (P < 0.01). Baicalin decreased metabolism of phenacetin and exhibited a mixed-type inhibition in rat liver microsomes, with a K(i) value of 88.1 μM in vitro. Moreover baicalin was a competitive displacer of theophylline from plasma protein in vitro. CONCLUSIONS The changes in Cmax, T(1/2), CL and AUC of theophylline due to baicalin may be attributed to two mechanisms, plasma protein binding displacement and CYP1A2 activity inhibition.
Collapse
Affiliation(s)
- Na Gao
- Department of Clinical Pharmacology, School of Medicine, Zhengzhou University, Zhengzhou 450052, China
| | | | | | | | | | | |
Collapse
|
6
|
Miyamoto H, Matsueda S, Komori K, Fumoto S, Nakashima M, Yoshikawa N, Hirata H, Shimokawa K, Ohwaki Y, Nishida K. Evaluation for effect of hypothermia on the disposition of 4-nitrophenol in rats by in-vitro metabolism study and rat liver perfusion system. J Pharm Pharmacol 2013; 65:1536-40. [DOI: 10.1111/jphp.12130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2013] [Accepted: 07/23/2013] [Indexed: 11/26/2022]
Abstract
Abstract
Objectives
The aim of this study was to evaluate the effect of hypothermia on the in-vivo pharmacokinetics of 4-nitrophenol (4NP) using rat liver homogenate and rat liver perfusion system.
Methods
Rat liver homogenate was incubated with 4NP, which is mainly metabolized by cytochrome P450 2E1, at 37, 34, 32 or 28°C. The Michaelis constant (Km) and maximum elimination velocity (Vmax) of 4NP were calculated by a Hanes–Woolf plot. The hepatic extraction ratio (Eh) of 4NP was evaluated in a rat liver perfusion study at 37, 34, 32 or 28°C. Moreover, the plasma concentration profiles of 4NP after its intravenous (i.v.) administration to rats were analysed by the moment theory and were compared with in-vitro parameters.
Key findings
While the Km of 4NP was not changed, the Vmax and Eh were reduced at low temperatures. The plasma concentrations of 4NP after its i.v. administration to rats were significantly increased at 28°C.
Conclusion
Changes in the pharmacokinetics of 4NP under hypothermic conditions were caused by alterations in Vmax and Eh. We may be able to predict the disposition of a drug by in-vitro studies.
Collapse
Affiliation(s)
- Hirotaka Miyamoto
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Satoshi Matsueda
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Kotaro Komori
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Shintaro Fumoto
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Mikiro Nakashima
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Naoki Yoshikawa
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Haruna Hirata
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Kenta Shimokawa
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Yuichi Ohwaki
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Koyo Nishida
- Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| |
Collapse
|
7
|
Shellhaas RA, Ng CM, Dillon CH, Barks JD, Bhatt-Mehta V. Population pharmacokinetics of phenobarbital in infants with neonatal encephalopathy treated with therapeutic hypothermia. Pediatr Crit Care Med 2013; 14:194-202. [PMID: 23254984 PMCID: PMC3717607 DOI: 10.1097/pcc.0b013e31825bbbc2] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
OBJECTIVE Phenobarbital is the first-line treatment for neonatal seizures. Many neonates with hypoxic ischemic encephalopathy are treated with therapeutic hypothermia, and about 40% have clinical seizures. Little is known about the pharmacokinetics of phenobarbital in infants with hypoxic ischemic encephalopathy who undergo therapeutic hypothermia. The objective of this study was to determine the effect of therapeutic hypothermia on phenobarbital pharmacokinetics, taking into account maturational changes. SETTING Level 3 neonatal ICU. PATIENTS Infants with hypoxic ischemic encephalopathy and suspected seizures, all treated with phenobarbital. Some of these infants also received treatment with therapeutic hypothermia. INTERVENTIONS None. DESIGN A retrospective cohort study of 39 infants with hypoxic ischemic encephalopathy treated with phenobarbital (20 were treated with therapeutic hypothermia and 19 were not). MEASUREMENTS AND MAIN RESULTS Data on phenobarbital plasma concentrations were collected in 39 subjects with hypoxic ischemic encephalopathy with or without therapeutic hypothermia. Using nonlinear mixed-effects modeling, population pharmacokinetics of phenobarbital were developed with a total of 164 plasma concentrations. A one-compartment model best described the pharmacokinetics. The clearance of phenobarbital was linearly related to body weight and matured with increasing age with a maturation half-life of 22.1 days. Therapeutic hypothermia did not influence the pharmacokinetic parameters of phenobarbital. CONCLUSIONS Therapeutic hypothermia does not influence the clearance of phenobarbital after accounting for weight and age. Standard phenobarbital dosing is appropriate for the initial treatment of seizures in neonates with hypoxic ischemic encephalopathy treated with therapeutic hypothermia.
Collapse
Affiliation(s)
| | - Chee M Ng
- Department of Pediatrics, School of Medicine, University of Pennsylvania and Department of Clinical Pharmacology and Therapeutics, Children’s Hospital of Philadelphia, Philadelphia, PA
| | - Christina H. Dillon
- College of Literature, Science, and the Arts, University of Michigan, Ann Arbor, MI
| | - John D.E. Barks
- Department of Pediatrics, University of Michigan, Ann Arbor, MI
| | - Varsha Bhatt-Mehta
- College of Pharmacy and Department of Pediatrics, School of Medicine, University of Michigan, Ann Arbor, MI
| |
Collapse
|
8
|
Gao N, Zou D, Qiao HL. Concentration-dependent inhibitory effect of Baicalin on the plasma protein binding and metabolism of chlorzoxazone, a CYP2E1 probe substrate, in rats in vitro and in vivo. PLoS One 2013; 8:e53038. [PMID: 23301016 PMCID: PMC3534641 DOI: 10.1371/journal.pone.0053038] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 11/22/2012] [Indexed: 12/02/2022] Open
Abstract
Some of the components found in herbs may be inhibitors or inducers of cytochrome P450 enzymes, which may therefore result in undesired herb-drug interactions. As a component extracted from Radix Scutellariae, the direct effect of baicalin on cytochrome P450 has not been investigated sufficiently. In this study, we investigated concentration-dependent inhibitory effect of baicalin on the plasma protein binding and metabolism of chlorzoxazone (CZN), a model CYP2E1 probe substrate, in rats in vitro and in vivo. Animal experiment was a randomized, three-period crossover design. Significant changes in pharmacokinetic parameters of CZN such as Cmax, t1/2 and Vd were observed after treatment with baicalin in vivo (P<0.05). Cmax decreased by 25% and 33%, whereas t1/2 increased by 34% and 53%, Vd increased by 37% and 50% in 225 mg/kg and 450 mg/kg baicalin-treated rats, respectively. The AUC and CL of CZN were not affected (P>0.05). Correlation analysis showed that the changes in CZN concentrations and baicalin concentrations were in good correlation (r>0.99). In vitro experiments, baicalin decreased the formation of 6-OH-chlorzoxazone in a concentration-dependent manner and exhibited a competitive inhibition in rat liver microsomes, with a Ki value of 145.8 µM. The values of Cmax/Ki were 20 and 39 after treatment with baicalin (225 and 450 mg/kg), respectively. Protein binding experiments in vivo showed that the plasma free-fraction (fu) of CZN increased 2.6-fold immediately after baicalin treatment (450 mg/kg) and in vitro showed that baicalin (125–2500 mg/L) increased the unbound CZN from 1.63% to 3.58%. The results indicate that pharmacokinetic changes in CZN are induced by inhibitory effect of baicalin on the plasma protein binding of CZN and CYP2E1 activity.
Collapse
Affiliation(s)
- Na Gao
- Department of Clinical Pharmacology, School of Medicine, Zhengzhou University, Zhengzhou, P. R. China
| | - Dan Zou
- Department of Histology and Embryology, Henan Medical College for Staff and Workers, Zhengzhou, P. R. China
| | - Hai-Ling Qiao
- Department of Clinical Pharmacology, School of Medicine, Zhengzhou University, Zhengzhou, P. R. China
- * E-mail:
| |
Collapse
|
9
|
Vaquero J. Therapeutic hypothermia in the management of acute liver failure. Neurochem Int 2012; 60:723-35. [DOI: 10.1016/j.neuint.2011.09.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 09/13/2011] [Accepted: 09/13/2011] [Indexed: 02/07/2023]
|
10
|
Kochanek PM, Fink EL, Bell MJ. Politics and hypothermia-what might they have in common? Editorial comment on silasi and colbourne, 2011. Ther Hypothermia Temp Manag 2012; 2:11-3. [PMID: 24717133 DOI: 10.1089/ther.2012.1504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Patrick M Kochanek
- Department of Critical Care Medicine, Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine and Children's Hospital of Pittsburgh , Pittsburgh, Pennsylvania
| | | | | |
Collapse
|
11
|
Empey PE, Miller TM, Philbrick AH, Melick JA, Kochanek PM, Poloyac SM. Mild hypothermia decreases fentanyl and midazolam steady-state clearance in a rat model of cardiac arrest. Crit Care Med 2012; 40:1221-8. [PMID: 22067624 PMCID: PMC3307845 DOI: 10.1097/ccm.0b013e31823779f9] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVES Therapeutic hypothermia is widely employed for neuroprotection after cardiac arrest. However, concern regarding elevated drug concentrations during hypothermia and increased adverse drug reaction risk complicates concurrent pharmacotherapy. Many commonly used medications in critically ill patients rely on the cytochrome P450 3A isoform for their elimination. Therefore, our study objectives were to determine the effect of mild hypothermia on the in vivo pharmacokinetics of fentanyl and midazolam, two clinically relevant cytochrome P450 3A substrates, after cardiac arrest and to investigate the mechanisms of these alterations. DESIGN Prospective, randomized, controlled study. SETTING University research laboratory. SUBJECTS Thirty-two adult male Sprague-Dawley rats. INTERVENTIONS An asphyxial cardiac arrest rat model was used and mild hypothermia (33°C) was induced 1 hr post injury by surface cooling and continued for 10 hrs to mimic the prolonged clinical application of hypothermia accompanied by intensive care interventions. Fentanyl and midazolam were independently administered by intravenous infusion and plasma and brain concentrations were analyzed using ultraperformance liquid chromatography tandem mass spectrometry. Cytochrome P450 3a2 protein expression was measured and a Michaelis-Menten enzyme kinetic analysis was performed at 37°C and 33°C using control rat microsomes. MEASUREMENTS AND MAIN RESULTS Mild hypothermia decreased the systemic clearance of both fentanyl (61.5 ± 11.5 to 48.9 ± 8.95 mL/min/kg; p < .05) and midazolam (89.2 ± 12.5 to 73.6 ± 12.1 mL/min/kg; p < .05) after cardiac arrest. The elevated systemic concentrations did not lead to parallel increased brain exposures of either drug. Mechanistically, no differences in cytochrome P450 3a2 expression was observed, but the in vitro metabolism of both drugs was decreased at 33°C vs. 37°C through reductions in enzyme metabolic capacity rather than substrate affinity. CONCLUSIONS Mild hypothermia reduces the systemic clearances of fentanyl and midazolam in rats after cardiac arrest through alterations in cytochrome P450 3a2 metabolic capacity rather than enzyme affinity as observed with other cytochrome P450s. Contrasting effects on blood and brain levels further complicates drug dosing. Consideration of the impact of hypothermia on medications whose clearance is dependent on P450 3A metabolism is warranted.
Collapse
Affiliation(s)
- Philip E Empey
- Department of Pharmacy and Therapeutics, School of Medicine, Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA, USA
| | | | | | | | | | | |
Collapse
|
12
|
Zhou J, Empey PE, Bies RR, Kochanek PM, Poloyac SM. Cardiac arrest and therapeutic hypothermia decrease isoform-specific cytochrome P450 drug metabolism. Drug Metab Dispos 2011; 39:2209-18. [PMID: 21868471 DOI: 10.1124/dmd.111.040642] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Mild therapeutic hypothermia is emerging clinically as a neuroprotection therapy for individuals experiencing cardiac arrest (CA); however, its effects combined with disease pathogenesis on drug disposition and response have not been fully elucidated. We determined the activities of four major hepatic-metabolizing enzymes (CYP3A, CYP2C, CYP2D, and CYP2E) during hypothermia after experimental CA in rats by evaluating the pharmacokinetics of their probe drugs as a function of altered body temperature. Animals were randomized into sham normothermia (37.5-38°C), CA normothermia, sham hypothermia (32.5-33°C), and CA hypothermia groups. Probe drugs (midazolam, diclofenac, dextromethorphan, and chlorzoxazone) were given simultaneously by intravenous bolus after temperature stabilization. Multiple blood samples were collected between 0 and 8 h after drug administration. Pharmacokinetic (PK) analysis was conducted using a noncompartmental approach and population PK modeling. Noncompartmental analysis showed that the clearance of midazolam (CYP3A) in CA hypothermia was reduced from sham normothermia rats (681.6 ± 190.0 versus 1268.8 ± 348.9 ml · h(-1) · kg(-1), p < 0.05). The clearance of chlorzoxazone (CYP2E) in CA hypothermia was also reduced from sham normothermia rats (229.6 ± 75.6 versus 561.89 ± 215.9 ml · h(-1) · kg(-1), p < 0.05). Population PK analysis further demonstrated the decreased clearance of midazolam (CYP3A) was associated with CA injury (p < 0.05). The decreased clearance of chlorzoxazone (CYP2E1) was also associated with CA injury (p < 0.01). Hypothermia was found to be associated with the decreased volume of distribution of midazolam (V(1)), dextromethorphan (V(1)), and peripheral compartment for chlorzoxazone (V(2)) (p < 0.05, p < 0.05, and p < 0.01, respectively). Our data indicate that hypothermia, CA, and their interaction alter cytochrome P450-isoform specific activities in an isoform-specific manner.
Collapse
Affiliation(s)
- Jiangquan Zhou
- Department of Pharmaceutical Sciences, University of Pittsburgh School of Pharmacy, Pittsburgh, PA 15261, USA
| | | | | | | | | |
Collapse
|
13
|
Zhou J, Poloyac SM. The effect of therapeutic hypothermia on drug metabolism and response: cellular mechanisms to organ function. Expert Opin Drug Metab Toxicol 2011; 7:803-16. [PMID: 21473710 DOI: 10.1517/17425255.2011.574127] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Therapeutic hypothermia is being employed clinically due to its neuro-protective benefits. Both critical illness and therapeutic hypothermia significantly affect drug disposition, potentially contributing to drug-therapy and drug-disease interactions. Currently, there is limited information on the known alterations in drug concentration and response during mild hypothermia treatment, and there is a limited understanding of the specific mechanisms that underlie alterations in drug concentrations and the potential clinical importance of these changes. AREAS COVERED A systemic review of the effect of therapeutic hypothermia on drug metabolism, disposition and response is provided. Specifically, the clinical and preclinical evidence of the effects of therapeutic hypothermia on blood flow, specific hepatic metabolism pathways, transporter function, renal excretion, pharmacodynamics and the effects during rewarming are reviewed. EXPERT OPINION Available evidence demonstrates that mild hypothermia decreases the clearance of a variety of drugs with apparently little change in drug-protein binding. Recent evidence suggests that the magnitude of the change is elimination route specific. Further research is needed to determine the impact of these alterations on both drug concentration and response in order to optimize the therapeutic hypothermia in this vulnerable patient population.
Collapse
Affiliation(s)
- Jiangquan Zhou
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, 3501 Terrace Street, Pittsburgh, PA 15261, USA
| | | |
Collapse
|
14
|
Filippi L, la Marca G, Cavallaro G, Fiorini P, Favelli F, Malvagia S, Donzelli G, Guerrini R. Phenobarbital for neonatal seizures in hypoxic ischemic encephalopathy: a pharmacokinetic study during whole body hypothermia. Epilepsia 2011; 52:794-801. [PMID: 21371018 DOI: 10.1111/j.1528-1167.2011.02978.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE Therapeutic hypothermia has recently been introduced to treat term newborns with hypoxic-ischemic encephalopathy, of whom more than half have seizures. Phenobarbital is widely used to treat neonatal seizures, but it is unknown whether its pharmacokinetics is affected by hypothermia. We evaluated the influence of hypothermia on phenobarbital pharmacokinetics in asphyxiated newborns. METHODS Nineteen term asphyxiated newborns treated with mild whole body hypothermia, started within 6 h after birth and protracted for 72 h, received phenobarbital for clinical seizures. Treatment schedule consisted of a loading dose of 20 mg/kg, titrated to response, up to a maximum dose of 40 mg/kg, followed by a maintenance dose of 2.5 or 1.5 mg/kg every 12 h. Phenobarbital concentrations were measured on 28 dried blood spots in each newborn. KEY FINDINGS Eighteen newborns showed plasma concentrations within the reference range after receiving a loading dose of 20 mg/kg. In the remaining newborn, who had received a loading dose of 35 mg/kg, phenobarbital concentrations exceeded the upper reference limit. Phenobarbital concentrations reached a virtual steady state in all newborns. Pharmacokinetic parameters were then calculated. Minimum and maximum concentration (24.7 ± 8.8 and 30.63 ± 10.3 mg/L), average plasma concentration (27.37 ± 9.4 mg/L), and half-life (173.9 ± 62.5 h) were considerably higher than reported in literature for normothermic newborns. Pharmacokinetic parameters did not differ significantly between infants receiving different maintenance doses. SIGNIFICANCE Phenobarbital administered to newborns under whole body hypothermia results in higher plasma concentrations and longer half-lives than expected in normothermic newborns.
Collapse
Affiliation(s)
- Luca Filippi
- Neonatal Intensive Care Unit, Department of Perinatal Medicine, A. Meyer University Children's Hospital, Florence, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Wang X, Hu L, Tong S, Zheng Y, Ye F, Lin D, Lin G, Zhang X, Wu H. Determination of Chlorzoxazone in Rat Plasma by LC-ESI-MS/MS and Its Application to a Pharmacokinetic Study. ANAL LETT 2010. [DOI: 10.1080/00032711003717430] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
16
|
van den Broek MP, Groenendaal F, Egberts AC, Rademaker CM. Effects of Hypothermia on Pharmacokinetics and Pharmacodynamics. Clin Pharmacokinet 2010; 49:277-94. [DOI: 10.2165/11319360-000000000-00000] [Citation(s) in RCA: 145] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
17
|
Abstract
At the 2(nd) International Brain Hypothermia conference, in Miami, the late Dr. Peter Safar was honored for his many contributions to the field of therapeutic hypothermia. Therapeutic hypothermia played a central role in his overall vision for optimized resuscitation and neurointensive care, across a large number of potential insults. The successful use of therapeutic hypothermia in comatose patients after cardiac arrest, for example, was already included in the historic first "ABCs" of resuscitation, published by Safar in 1964. This review addresses key historical events in the development and implementation of therapeutic hypothermia across a number of central nervous system insults. A discussion of future potential uses of this therapy in a variety of applications as part of the Safar vision is also presented.
Collapse
Affiliation(s)
- Patrick M Kochanek
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260, USA.
| | | | | |
Collapse
|
18
|
Moderate hypothermia prevents cardiac arrest-mediated suppression of drug metabolism and induction of interleukin-6 in rats. Crit Care Med 2009; 37:263-9. [PMID: 19050605 DOI: 10.1097/ccm.0b013e3181931ed3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
OBJECTIVE Therapeutic hypothermia is being clinically used to reduce neurologic deficits after cardiac arrest (CA). Patients receiving hypothermia after CA receive a wide-array of medications. During hypothermia, drug metabolism is markedly reduced. Little, however, is known about the impact of hypothermia on drug metabolism after rewarming. The objective of this study was to examine the effect of CA and hypothermia on the functional regulation of two major drug metabolizing cytochrome P450 (CYP) isoforms. DESIGN Laboratory investigation. SETTING University pharmacy school and animal research facility. SUBJECTS Thirty-six male Sprague-Dawley rats. INTERVENTIONS Hypothermia was induced via surface cooling in a rat CA model and maintained for 3 hrs. Animals were killed at 5 or 24 hrs and liver was analyzed for hepatic activity and mRNA expression of CYP3A2 and CYP2E1. Plasma interleukin-6 (IL-6) concentrations were determined. The effect of IL-6 on pregnane X receptor-mediated transcription of the rat CYP3A2 promoter was evaluated via luciferase reporter in HepG2 cells. MEASUREMENTS AND MAIN RESULTS At 24 hrs after CA a decrease in CYP3A2 and CYP2E1 activity was observed, 55.7% +/- 12.8% and 46.8% +/- 29.7% of control, respectively (p < 0.01). CA decreased CYP3A2 mRNA (p < 0.05), but not CYP2E1 mRNA. Expression of other pregnane X receptor target enzymes and transporter genes were similarly down-regulated. CA also produced an approximately ten-fold increase in plasma IL-6. CA-mediated inhibition of CYP3A2 and CYP2E1 was attenuated by hypothermia, as was the increase in IL-6. Furthermore, IL-6 attenuated pregnane X receptor-mediated transcription of the CYP3A2 promoter. CONCLUSIONS CA produces CYP3A2 down-regulation at 24 hrs, potentially via IL-6 effects on pregnane X receptor-mediated transcription. Also, hypothermia attenuates the CA-mediated down-regulation, thereby normalizing drug metabolism after rewarming.
Collapse
|
19
|
Attenuating the effects of cardiac arrest on hepatic drug metabolism: just chill out! Crit Care Med 2009; 37:369-70. [PMID: 19112312 DOI: 10.1097/ccm.0b013e31819303c7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
20
|
Tortorici MA, Kochanek PM, Poloyac SM. Effects of hypothermia on drug disposition, metabolism, and response: A focus of hypothermia-mediated alterations on the cytochrome P450 enzyme system. Crit Care Med 2007; 35:2196-204. [PMID: 17855837 DOI: 10.1097/01.ccm.0000281517.97507.6e] [Citation(s) in RCA: 291] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVES Therapeutic hypothermia has been shown to decrease neurologic damage in patients experiencing out-of-hospital cardiac arrest. In addition to being treated with hypothermia, critically ill patients are treated with an extensive pharmacotherapeutic regimen. The effects of hypothermia on drug disposition increase the probability for unanticipated toxicity, which could limit its putative benefit. This review examines the effects of therapeutic hypothermia on the disposition, metabolism, and response of drugs commonly used in the intensive care unit, with a focus on the cytochrome P450 enzyme system. DATA SOURCES AND STUDY SELECTION A MEDLINE/PubMed search from 1965 to June 2006 was conducted using the search terms hypothermia, drug metabolism, P450, critical care, cardiac arrest, traumatic brain injury, and pharmacokinetics. DATA EXTRACTION AND SYNTHESIS Twenty-one studies were included in this review. The effects of therapeutic hypothermia on drug disposition include both the effects during cooling and the effects after rewarming on drug metabolism and response. The studies cited in this review demonstrate that the addition of mild to moderate hypothermia decreases the systemic clearance of cytochrome P450 metabolized drugs between approximately 7% and 22% per degree Celsius below 37degreesC during cooling. The addition of hypothermia decreases the potency and efficacy of certain drugs. CONCLUSIONS This review provides evidence that the therapeutic index of drugs is narrowed during hypothermia. The magnitude of these alterations indicates that intensivists must be aware of these alterations in order to maximize the therapeutic efficacy of this modality. In addition to increased clinical attention, future research efforts are essential to delineate precise dosing guidelines and mechanisms of the effect of hypothermia on drug disposition and response.
Collapse
Affiliation(s)
- Michael A Tortorici
- University of Pittsburgh School of Pharmacy, Department of Pharmaceutical Sciences, Pittsburgh, PA, USA
| | | | | |
Collapse
|
21
|
|