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Guo P, Zhang WJ, Lian TH, Zhang WJ, He MY, Zhang YN, Huang Y, Ding DY, Guan HY, Li JH, Li DN, Luo DM, Zhang WJ, Yue H, Wang XM, Zhang W. Alzheimer's disease with sleep insufficiency: a cross-sectional study on correlations among clinical characteristics, orexin, its receptors, and the blood-brain barrier. Neural Regen Res 2023; 18:1757-1762. [PMID: 36751802 PMCID: PMC10154498 DOI: 10.4103/1673-5374.360250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Previous studies have shown that reduced sleep duration, sleep fragmentation, and decreased sleep quality in patients with Alzheimer's disease are related to dysfunction in orexin signaling. At the same time, blood-brain barrier disruption is considered an early biomarker of Alzheimer's disease. However, currently no report has examined how changes in orexin signaling relate to changes in the blood-brain barrier of patients who have Alzheimer's disease with sleep insufficiency. This cross-sectional study included 50 patients with Alzheimer's disease who received treatment in 2019 at Beijing Tiantan Hospital. Patients were divided into two groups: those with insufficient sleep (sleep duration ≤ 6 hours, n = 19, age 61.58 ± 8.54 years, 10 men) and those with normal sleep durations (sleep duration > 6 hours, n = 31, age 63.19 ± 10.09 years, 18 men). Demographic variables were collected to evaluate cognitive function, neuropsychiatric symptoms, and activities of daily living. The levels of orexin, its receptor proteins, and several blood-brain barrier factors were measured in cerebrospinal fluid. Sleep insufficiency was associated with impaired overall cognitive function that spanned multiple cognitive domains. Furthermore, levels of orexin and its receptors were upregulated in the cerebrospinal fluid, and the blood-brain barrier was destroyed. Both these events precipitated each other and accelerated the progression of Alzheimer's disease. These findings describe the clinical characteristics and potential mechanism underlying Alzheimer's disease accompanied by sleep deprivation. Inhibiting the upregulation of elements within the orexin system or preventing the breakdown of the blood-brain barrier could thus be targets for treating Alzheimer's disease.
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Affiliation(s)
- Peng Guo
- Center for Cognitive Neurology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Wen-Jing Zhang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Teng-Hong Lian
- Center for Cognitive Neurology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Wei-Jiao Zhang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Ming-Yue He
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Ya-Nan Zhang
- Department of Blood Transfusion, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Yue Huang
- Department of Neurology; China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; Department of Pharmacology, School of Medical Sciences, Faculty of Medicine & Health, University of New South Wales, Sydney, Australia
| | - Du-Yu Ding
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Hui-Ying Guan
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Jing-Hui Li
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Dan-Ning Li
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Dong-Mei Luo
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Wei-Jia Zhang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Hao Yue
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Xiao-Min Wang
- Department of Physiology, Capital Medical University, Beijing, China
| | - Wei Zhang
- Center for Cognitive Neurology, Department of Neurology; China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University; Center of Parkinson's Disease, Beijing Institute for Brain Disorders; Beijing Key Laboratory on Parkinson's Disease, Beijing, China
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Guo P, Wang RD, Lian TH, Ding DY, Zhang YN, Zhang WJ, Li DN, Li LX, Li JH, Guan HY, Yu SY, Liu L, Hu Y, Zuo LJ, Yu QJ, Wang XM, Zhang W. Olfactory Dysfunction and Its Association With Neuropathologic Proteins in Cerebrospinal Fluid From Patients With Parkinson Disease. Front Aging Neurosci 2020; 12:594324. [PMID: 33362530 PMCID: PMC7759606 DOI: 10.3389/fnagi.2020.594324] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 11/23/2020] [Indexed: 01/07/2023] Open
Abstract
Background and Purpose: Olfactory dysfunction (OD) is a common non-motor symptom of Parkinson disease (PD). However, the relationship between OD and neuropathologic proteins in cerebrospinal fluid (CSF) from PD patients remains unclear. Methods: 166 PD patients were included in the study. Overall olfactory function was assessed by summing up the scores of olfactory threshold, discrimination, and identification by a Sniffin' Sticks test, based on which, patients were divided into PD with OD (PD-OD) and PD with no OD (PD-NOD) groups. CSF samples were obtained from 76 PD patients. The levels of neuropathologic proteins, including α-Synuclein, Aβ1-42, total tau (T-tau), and multiple forms of phosphorylated tau (P-tau) in CSF were measured by an enzyme-linked immunosorbent assay. Results: out of the 166 PD patients, 103 cases (62.0%) had OD. The scores of overall olfactory functions, and olfactory threshold, discrimination, and identification in the PD-OD group were all significantly lower than that in the PD-NOD group (P < 0.001). α-Synuclein level in CSF was significantly higher in the PD-OD group than the PD-NOD group (P < 0.05), and was significantly and negatively correlated with the scores of overall olfactory function, and olfactory discrimination and identification (P < 0.05). Aβ1-42 level in CSF was higher in the PD-OD group than the PD-NOD group, and was significantly and negatively correlated with the olfactory identification score (P < 0.05). T-tau level in CSF was significantly lower in the PD-OD group than the PD-NOD group (P < 0.05), and was significantly and positively correlated with the olfactory discrimination score (P < 0.05). There was no significant difference in P-tau level in CSF between the PD-OD and PD-NOD groups and no correlation between OD score and P-tau level in CSF. Conclusions: PD-OD includes the impairments of olfactory threshold, discrimination, and identification, and is associated with the significant elevation of α-Synuclein and the decrease of the T-tau level in CSF.
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Affiliation(s)
- Peng Guo
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Rui-Dan Wang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Teng-Hong Lian
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Du-Yu Ding
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Ya-Nan Zhang
- Department of Blood Transfusion, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Wei-Jiao Zhang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Dan-Ning Li
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Li-Xia Li
- Department of General Internal Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Jing-Hui Li
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Hui-Ying Guan
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Shu-Yang Yu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Li Liu
- Department of General Internal Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Yang Hu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Li-Jun Zuo
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Qiu-Jin Yu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Xiao-Min Wang
- Department of Physiology, Capital Medical University, Beijing, China
| | - Wei Zhang
- Department of Neurology, Center for Cognitive Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,China National Clinical Research Center for Neurological Disease, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,Center of Parkinson's Disease, Beijing Institute for Brain Disorders, Beijing, China.,Beijing Key Laboratory on Parkinson Disease, Beijing, China
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Yu SY, Lian TH, Guo P, Li LX, Ding DY, Li DN, Liu L, Zhao H, Hu Y, Zuo LJ, Gao JH, Yu QJ, Jin Z, Wang RD, Zhu RY, Wang XM, Zhang W. Correlations of apathy with clinical symptoms of Alzheimer's disease and olfactory dysfunctions: a cross-sectional study. BMC Neurol 2020; 20:416. [PMID: 33189129 PMCID: PMC7666513 DOI: 10.1186/s12883-020-01978-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Accepted: 10/23/2020] [Indexed: 12/14/2022] Open
Abstract
Background Apathy is one of the most common symptoms of Alzheimer’s disease (AD), however, correlations of apathy with demographic variables, cognitive functions, neuropsychiatric symptoms, activity of daily living and olfactory functions in AD patients are still lacking comprehensive investigations. Methods This is a cross-sectional study. Total 124 typical AD patients were consecutively recruited from April 2014 to April 2017. In 124 AD patients, 47 cases (37.9%) were male and 77 cases were female; patients’ age were 43–93 years with an average of 68 years. Patients were divided into AD with apathy (AD-A) and AD with no apathy (AD-NA) groups according to the score of Modified Apathy Evaluation Scale, then were evaluated cognitive functions, neuropsychiatric symptoms and activity of daily living, and tested olfactory functions. Above variables were compared between AD-A and AD-NA groups. Further correlation analyses and linear regression analysis were performed between apathy and above variables. Results Compared with AD-NA group, global cognitive level, verbal memory, verbal fluency and activity of daily living were significantly compromised in AD-A group (P < 0.002); depression and agitation were severely displayed in AD-A group (P < 0.002). Apathy was negatively correlated with global cognitive function, verbal memory, verbal fluency and activity of daily living (P < 0.05). There was no significant difference of olfactory functions between the two groups (P > 0.002), and correlations between apathy and olfactory threshold, olfactory identification and global olfactory function were significant (P < 0.05) but quite weak (|r| < 0.3). Further linear regression analysis showed that only verbal fluency and instrumental activities of daily living were independently associated with apathy. Conclusions Independent correlations among apathy, verbal fluency and instrumental activities of daily living in AD patients might be related to the common brain area involved in their pathogeneses.
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Affiliation(s)
- Shu-Yang Yu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Teng-Hong Lian
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Peng Guo
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Li-Xia Li
- Department of General Internal Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Du-Yu Ding
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Dan-Ning Li
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Li Liu
- Department of General Internal Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Hui Zhao
- Department of General Internal Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Yang Hu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Li-Jun Zuo
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Jun-Hua Gao
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Qiu-Jin Yu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Zhao Jin
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Rui-Dan Wang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Rong-Yan Zhu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Xiao-Min Wang
- Department of Physiology, Capital Medical University, Beijing, 100069, China
| | - Wei Zhang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China. .,China National Clinical Research Center for Neurological Disease, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China. .,Center of Parkinson's Disease, Beijing Institute for Brain Disorders, Beijing, 100053, China. .,Beijing Key Laboratory on Parkinson Disease, Beijing, 100053, China.
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Yu SY, Zhu WL, Guo P, Li SW, Liu YO, Lian TH, Ding DY, Li DN, Li LX, Liu L, Zhao H, Zuo LJ, Hu Y, Yu QJ, Jin Z, Wang RD, Gao JH, Zhu RY, Wang XM, Zhang W. Clinical features and brain structural changes in magnetic resonance imaging in Alzheimer's disease patients with apathy. Aging (Albany NY) 2020; 12:19083-19094. [PMID: 33041262 PMCID: PMC7732276 DOI: 10.18632/aging.103705] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 07/06/2020] [Indexed: 01/24/2023]
Abstract
BACKGROUND Apathy is common in Alzheimer's disease (AD) patients. However, its relation with other clinical symptoms in AD and brain structural changes in magnetic resonance imaging is unclear. RESULTS Compared with AD with no apathy group, cognitive function and activities of daily living were significantly impaired and neuropsychiatric symptoms were obviously presented in AD with apathy group (P<0.05). The frequency of Apolipoprotein E genotypes was not significantly different (P>0.05). Correlation analyses and multiple linear analyses revealed that thickness of left temporal pole and volume of posterior corpus callosum were significantly and negatively correlated with Modified Apathy Estimation Scale score in AD patients (P<0.05). CONCLUSIONS Apathy with AD is positively correlated with cognitive impairment, neuropsychiatric symptoms and poor activities of daily living. Atrophy of left temporal pole and posterior corpus callosum presented by MRI is positively related with apathy of AD. METHODS In this study, 137 AD patients were recruited and divided into AD with apathy group and AD with no apathy group according to Modified Apathy Estimation Scale score. We evaluated patients' cognitive function, neuropsychiatric symptoms and activities of daily living, detected the frequency of Apolipoprotein E genotypes and measured cortical thickness and volume by magnetic resonance imaging (MRI).
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Affiliation(s)
- Shu-Yang Yu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China,China National Clinical Research Center for Neurological Disease, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Wan-Lin Zhu
- China National Clinical Research Center for Neurological Disease, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China,China National Clinical Research Center for Neurological Disease, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Peng Guo
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Shao-Wu Li
- Beijing Neurosurgical Institute, Beijing 100070, China
| | - Ya-Ou Liu
- Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Teng-Hong Lian
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Du-Yu Ding
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Dan-Ning Li
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Li-Xia Li
- Department of General Internal Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Li Liu
- Department of General Internal Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Hui Zhao
- Department of General Internal Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Li-Jun Zuo
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Yang Hu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Qiu-Jin Yu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Zhao Jin
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Rui-Dan Wang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Jun-Hua Gao
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Rong-Yan Zhu
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China
| | - Xiao-Min Wang
- Department of Physiology, Capital Medical University, Beijing 100069, China
| | - Wei Zhang
- Center for Cognitive Neurology, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China,China National Clinical Research Center for Neurological Disease, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, China;,Center of Parkinson's Disease, Beijing Institute for Brain Disorders, Beijing 100053, China,Beijing Key Laboratory on Parkinson's Disease, Beijing 100053, China
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Li DN, He A, Wang Y, Liang Y, Li ZY, Men JX, Zhan XM. [Three lethal cases of Angiostrongylus cantonensis infected children]. Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi 2003; 19:310-1. [PMID: 12572053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To offer approaches to diagnosis and treatment of Angiostrongylus cantonensis infection on the basis of analyzing three lethal cases of the disease. METHODS Clinical manifestations, pathological changes and species identification were pursued. RESULTS Angiostrongyliasis is usually neglected in medical departments. The three cases here reported were all misdiagnosed and had not receiced anthelmintic treatment hence fatality ensued. CONCLUSION Early examination of CSF, bronchial lavage fluid and feces is urged so as to secure accurate diagnosis and conduct efficacious anthelmintic therapy to cure the patients.
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Affiliation(s)
- D N Li
- Department of Parasitology, Sun Yat-Sen University of Medical Sciences, Guangzhou 510089
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Abstract
Proteases perform two key roles in the class II MHC antigen processing pathway. They initiate removal of the invariant chain chaperone for class II MHC and they generate peptides from foreign and self proteins for eventual capture and display to T cells. How a balance is achieved between generation of suitable peptides versus their complete destruction in an aggressive proteolytic environment is not known. Nor is it known in most cases which proteases are actually involved in antigen processing. Our recent studies have identified asparagine endopeptidase (AEP or legumain) as an enzyme that contributes to both productive and destructive antigen processing in the class II MHC pathway. The emerging consensus seems to be that individual proteolytic enzymes make clear and non-redundant contributions to antigen processing.
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Affiliation(s)
- C Watts
- Division of Cell Biology Immunology, School of Life Sciences, University of Dundee, DD1 5EH, United Kingdom.
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Li DN, Seidel A, Pritchard MP, Wolf CR, Friedberg T. Polymorphisms in P450 CYP1B1 affect the conversion of estradiol to the potentially carcinogenic metabolite 4-hydroxyestradiol. Pharmacogenetics 2000; 10:343-53. [PMID: 10862525 DOI: 10.1097/00008571-200006000-00008] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Most drug metabolizing cytochrome P450s (P450) are predominantly expressed in the liver. In contrast, human CYP1B1 is an extrahepatic P450 which is overexpressed in many tumours and has been strongly implicated in the activation of carcinogens. Rare allelic variants of the CYP1B1 gene which encode an inactive protein have been identified. However, four polymorphisms which most likely do not abolish functionality have been described. In this report, we have characterized the functional consequences of these. A CYP1B1 cDNA, identical to a cDNA published previously, served as a template to introduce allelic changes either separately or in combination. The resulting effects on CYP1B1 activity were determined in membranes isolated from Escherichia coli which coexpressed CYP1B1 together with P450 reductase. None of the allelic changes affected the CYP1B1 expression level. The allelic changes Arg48 to Gly, Ala19 to Ser and Asn453 to Ser had little influence on the Vmax and the Km of the CYP1B1 mediated 2- and 4-hydroxylation of estradiol. In contrast, the Km of these metabolic pathways was increased at least three-fold by the allelic change Va432 to Leu or by simultaneously changing Val432 to Leu and Asn453 to Ser. However, these alterations had little effect on the kinetic parameters of other CYP1B1 mediated reactions such as the epoxidation of (-)-trans-(7R,8R)-benzo[a]pyrene 7,8-dihydrodiol as determined by (r-7,t-8,t-9,c-10)-benzo[a]pyrene tetraol formation, or such as the O-dealkylation of ethoxyresorufin and the 1'-hydroxylation of bufuralol. Molecular modelling suggests that amino acid residue 432 of CYP1B1 may be involved in the interaction between CYP1B1 and P450 reductase. Since 4-hydroxyestradiol has been implicated in hormonal carcinogenesis and CYP1B1 is expressed in target tissues, the data presented demonstrate that polymorphisms in CYP1B1 have the potential to affect disease susceptibility.
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Affiliation(s)
- D N Li
- Biomedical Research Centre, University of Dundee Medical School, Ninewells Hospital, UK
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Li DN, Pritchard MP, Hanlon SP, Burchell B, Wolf CR, Friedberg T. Competition between cytochrome P-450 isozymes for NADPH-cytochrome P-450 oxidoreductase affects drug metabolism. J Pharmacol Exp Ther 1999; 289:661-7. [PMID: 10215637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
NADPH-cytochrome P-450 oxidoreductase (CPR) is essential for the catalytic activity of cytochrome P-450 (P-450). On a molar basis, the amount of P-450 exceeds that of CPR in human liver. In this study, we investigated whether drug-drug interactions can occur as a result of competition between P-450 isozymes for this ancillary protein. For this purpose, combinations of P-450 isozymes were coexpressed together with P-450 reductase in Escherichia coli. We show that testosterone inhibited the CYP2D6-mediated bufuralol 1'-hydroxylase activity in bacterial membranes containing both CYP2D6 and CYP3A4 but not in membranes containing CYP2D6 alone. Conversely, bufuralol inhibited the CYP3A4-mediated testosterone 6beta-hydroxylase activity in bacterial membranes containing both CYP3A4 and CYP2D6 but not in membranes containing only CYP3A4. In each case, inhibition was seen even at a P-450 to P-450 reductase ratio of 1.9:1, which is more favorable than the ratio of 4 reported for human liver. The physiological significance of this mechanism was demonstrated by the observation that testosterone inhibited several prototypical P-450 enzyme activities, such as bufuralol 1'-hydroxylase, coumarin 7-hydroxylase, and 7-ethoxyresorufin O-dealkylase, in human liver microsomes, but not if tested against a panel of bacterial membranes containing the human P-450 isozymes that mainly catalyze these reactions.
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Affiliation(s)
- D N Li
- Biomedical Research Centre, University of Dundee, Ninewells Hospital and Medical School, Dundee, United Kingdom
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Pritchard MP, Ossetian R, Li DN, Henderson CJ, Burchell B, Wolf CR, Friedberg T. A general strategy for the expression of recombinant human cytochrome P450s in Escherichia coli using bacterial signal peptides: expression of CYP3A4, CYP2A6, and CYP2E1. Arch Biochem Biophys 1997; 345:342-54. [PMID: 9308909 DOI: 10.1006/abbi.1997.0265] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Heterologous expression of unmodified recombinant human cytochrome P450 enzymes (P450s) in Escherichia coli has proved to be extremely difficult. To date, high-level expression has only been achieved after altering the 5'-end of the native cDNA, resulting in amino acid changes within the P450 protein chain. We have devised a strategy whereby unmodified P450s can be expressed to high levels in E. coli, by making NH2-terminal translational fusions to bacterial leader sequences. Using this approach, we initially tested two leader sequences, pelB and ompA, fused to CYP3A4. These were compared with an expression construct producing a conventional NH2-terminally modified CYP3A4 (17alpha-3A4). Both leader constructs produced spectrally active, functional protein. Furthermore, the ompA-3A4 fusion gave higher levels of expression, and a marked improvement in the recovery of active P450 in bacterial membrane fractions, when compared with 17alpha-3A4. We then tested the ompA leader with CYP2A6 and CYP2E1, again comparing with the conventional (17alpha-) approach. As before, the leader construct produced active enzyme, and, for CYP2E1 at least, gave a higher level of expression than the 17alpha-construct. The ompA fusion strategy thus appears to represent a significant advance for the expression of P450s in E. coli, circumventing the previous need for individual optimization of P450 sequences for expression.
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Affiliation(s)
- M P Pritchard
- Biomedical Research Centre, University of Dundee, Scotland, United Kingdom
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Li DN. [Acute polyradiculoneuritis treated with corticosteroids]. Zhonghua Shen Jing Jing Shen Ke Za Zhi 1982; 15:72-4. [PMID: 7128312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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11
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Li DN. [A long-term follow-up study of internal carotid artery occlusion with radionuclide cerebral angiography (author's transl)]. Zhonghua Shen Jing Jing Shen Ke Za Zhi 1982; 15:16-9. [PMID: 7094723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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12
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Li DN. [The relationship between the clinical diagnosis and cerebral angiography in occlusion of the carotid arterial system (author's transl)]. Zhonghua Shen Jing Jing Shen Ke Za Zhi 1981; 14:231-3. [PMID: 7343234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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13
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Li DN. [Disorder of body image in multiple sclerosis patients---report of 4 cases (author's transl)]. Zhonghua Shen Jing Jing Shen Ke Za Zhi 1981; 13:109-11. [PMID: 7307762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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