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Petkevicius K, Palmgren H, Glover MS, Ahnmark A, Andréasson AC, Madeyski-Bengtson K, Kawana H, Allman EL, Kaper D, Uhrbom M, Andersson L, Aasehaug L, Forsström J, Wallin S, Ahlstedt I, Leke R, Karlsson D, González-King H, Löfgren L, Nilsson R, Pellegrini G, Kono N, Aoki J, Hess S, Sienski G, Pilon M, Bohlooly-Y M, Maresca M, Peng XR. TLCD1 and TLCD2 regulate cellular phosphatidylethanolamine composition and promote the progression of non-alcoholic steatohepatitis. Nat Commun 2022; 13:6020. [PMID: 36241646 PMCID: PMC9568529 DOI: 10.1038/s41467-022-33735-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 09/29/2022] [Indexed: 11/29/2022] Open
Abstract
The fatty acid composition of phosphatidylethanolamine (PE) determines cellular metabolism, oxidative stress, and inflammation. However, our understanding of how cells regulate PE composition is limited. Here, we identify a genetic locus on mouse chromosome 11, containing two poorly characterized genes Tlcd1 and Tlcd2, that strongly influences PE composition. We generated Tlcd1/2 double-knockout (DKO) mice and found that they have reduced levels of hepatic monounsaturated fatty acid (MUFA)-containing PE species. Mechanistically, TLCD1/2 proteins act cell intrinsically to promote the incorporation of MUFAs into PEs. Furthermore, TLCD1/2 interact with the mitochondria in an evolutionarily conserved manner and regulate mitochondrial PE composition. Lastly, we demonstrate the biological relevance of our findings in dietary models of metabolic disease, where Tlcd1/2 DKO mice display attenuated development of non-alcoholic steatohepatitis compared to controls. Overall, we identify TLCD1/2 proteins as key regulators of cellular PE composition, with our findings having broad implications in understanding and treating disease. The regulation of cellular phosphatidylethanolamine (PE) acyl chain composition is poorly understood. Here, the authors show that TLCD1 and TLCD2 proteins mediate the formation of monounsaturated fatty acid-containing PE species and promote the progression of non-alcoholic steatohepatitis.
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Affiliation(s)
- Kasparas Petkevicius
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden. .,Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden.
| | - Henrik Palmgren
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden.,Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Matthew S Glover
- Dynamic Omics, Centre for Genomics Research, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD, USA
| | - Andrea Ahnmark
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Anne-Christine Andréasson
- Bioscience Cardiovascular, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | | | - Hiroki Kawana
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan.,Advanced Research & Development Programs for Medical Innovation (AMED-LEAP), Tokyo, Japan
| | - Erik L Allman
- Dynamic Omics, Centre for Genomics Research, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD, USA
| | - Delaney Kaper
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Martin Uhrbom
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Liselotte Andersson
- Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Leif Aasehaug
- Bioscience Cardiovascular, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Johan Forsström
- Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Simonetta Wallin
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Ingela Ahlstedt
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Renata Leke
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Daniel Karlsson
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Hernán González-King
- Bioscience Cardiovascular, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Lars Löfgren
- Translational Science and Experimental Medicine, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Ralf Nilsson
- Translational Science and Experimental Medicine, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Giovanni Pellegrini
- Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Nozomu Kono
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Junken Aoki
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan.,Advanced Research & Development Programs for Medical Innovation (AMED-LEAP), Tokyo, Japan
| | - Sonja Hess
- Dynamic Omics, Centre for Genomics Research, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD, USA
| | - Grzegorz Sienski
- Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Marc Pilon
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | | | - Marcello Maresca
- Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Xiao-Rong Peng
- Bioscience Metabolism, Research and Early Development Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
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Wilhelmsson U, Lebkuechner I, Leke R, Marasek P, Yang X, Antfolk D, Chen M, Mohseni P, Lasič E, Bobnar ST, Stenovec M, Zorec R, Nagy A, Sahlgren C, Pekna M, Pekny M. Nestin Regulates Neurogenesis in Mice Through Notch Signaling From Astrocytes to Neural Stem Cells. Cereb Cortex 2019; 29:4050-4066. [DOI: 10.1093/cercor/bhy284] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 10/05/2018] [Indexed: 12/21/2022] Open
Abstract
Abstract
The intermediate filament (nanofilament) protein nestin is a marker of neural stem cells, but its role in neurogenesis, including adult neurogenesis, remains unclear. Here, we investigated the role of nestin in neurogenesis in adult nestin-deficient (Nes–/–) mice. We found that the proliferation of Nes–/– neural stem cells was not altered, but neurogenesis in the hippocampal dentate gyrus of Nes–/– mice was increased. Surprisingly, the proneurogenic effect of nestin deficiency was mediated by its function in the astrocyte niche. Through its role in Notch signaling from astrocytes to neural stem cells, nestin negatively regulates neuronal differentiation and survival; however, its expression in neural stem cells is not required for normal neurogenesis. In behavioral studies, nestin deficiency in mice did not affect associative learning but was associated with impaired long-term memory.
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Affiliation(s)
- Ulrika Wilhelmsson
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Isabell Lebkuechner
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Renata Leke
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Pavel Marasek
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Xiaoguang Yang
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Daniel Antfolk
- Faculty of Science and Engineering, Biosciences, Åbo Akademi University, Turku, Finland
| | - Meng Chen
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Paria Mohseni
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, ON, Canada
| | - Eva Lasič
- Laboratory of Neuroendocrinology–Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Saša Trkov Bobnar
- Laboratory of Neuroendocrinology–Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
- Celica BIOMEDICAL, Ljubljana, Slovenia
| | - Matjaž Stenovec
- Laboratory of Neuroendocrinology–Molecular Cell Physiology, Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
- Celica BIOMEDICAL, Ljubljana, Slovenia
| | | | - Andras Nagy
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, ON, Canada
- Australian Regenerative Medicine Institute, Monash University, Melbourne, VIC, Australia
| | - Cecilia Sahlgren
- Faculty of Science and Engineering, Biosciences, Åbo Akademi University, Turku, Finland
| | - Marcela Pekna
- Laboratory of Regenerative Neuroimmunology, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia
- University of Newcastle, Newcastle, NSW, Australia
| | - Milos Pekny
- Laboratory of Astrocyte Biology and CNS Regeneration, Center for Brain Repair, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia
- University of Newcastle, Newcastle, NSW, Australia
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3
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Mbanya A, Ngandeu A, Kamwa V, Donfack OT, Lontchi É, Leke R, Mbanya JC, Sobngwi E. Metabolic features associated with positivity to ZnT8 autoantibody in sub-Saharan African young-onset diabetes patients. Diabetes Metab 2016; 42:204-6. [PMID: 26775084 DOI: 10.1016/j.diabet.2015.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 12/09/2015] [Accepted: 12/11/2015] [Indexed: 10/22/2022]
Affiliation(s)
- A Mbanya
- National Obesity Center, Yaoundé Central Hospital and Department of Internal Medecine, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, P.O. Box 7535, Yaoundé, Cameroon
| | - A Ngandeu
- National Obesity Center, Yaoundé Central Hospital and Department of Internal Medecine, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, P.O. Box 7535, Yaoundé, Cameroon
| | - V Kamwa
- National Obesity Center, Yaoundé Central Hospital and Department of Internal Medecine, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, P.O. Box 7535, Yaoundé, Cameroon
| | - O T Donfack
- Laboratory of Molecular Medicine and Metabolism, Biotechnology Centre, Nkolbisson, University of Yaoundé 1, Yaoundé, Cameroon
| | - É Lontchi
- Laboratory of Molecular Medicine and Metabolism, Biotechnology Centre, Nkolbisson, University of Yaoundé 1, Yaoundé, Cameroon; Université Paris Diderot, Paris, France
| | - R Leke
- Laboratory of Molecular Medicine and Metabolism, Biotechnology Centre, Nkolbisson, University of Yaoundé 1, Yaoundé, Cameroon
| | - J-C Mbanya
- National Obesity Center, Yaoundé Central Hospital and Department of Internal Medecine, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, P.O. Box 7535, Yaoundé, Cameroon; Laboratory of Molecular Medicine and Metabolism, Biotechnology Centre, Nkolbisson, University of Yaoundé 1, Yaoundé, Cameroon; Department of Internal Medicine, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon
| | - E Sobngwi
- National Obesity Center, Yaoundé Central Hospital and Department of Internal Medecine, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, P.O. Box 7535, Yaoundé, Cameroon; Laboratory of Molecular Medicine and Metabolism, Biotechnology Centre, Nkolbisson, University of Yaoundé 1, Yaoundé, Cameroon; Department of Internal Medicine, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon.
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4
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Leke R, Escobar TDC, Rao KVR, Silveira TR, Norenberg MD, Schousboe A. Expression of glutamine transporter isoforms in cerebral cortex of rats with chronic hepatic encephalopathy. Neurochem Int 2015; 88:32-7. [PMID: 25842041 DOI: 10.1016/j.neuint.2015.03.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 03/13/2015] [Accepted: 03/18/2015] [Indexed: 01/19/2023]
Abstract
Hepatic encephalopathy (HE) is a neuropsychiatric disorder that occurs due to acute and chronic liver diseases, the hallmark of which is the increased levels of ammonia and subsequent alterations in glutamine synthesis, i.e. conditions associated with the pathophysiology of HE. Under physiological conditions, glutamine is fundamental for replenishment of the neurotransmitter pools of glutamate and GABA. The different isoforms of glutamine transporters play an important role in the transfer of this amino acid between astrocytes and neurons. A disturbance in the GABA biosynthetic pathways has been described in bile duct ligated (BDL) rats, a well characterized model of chronic HE. Considering that glutamine is important for GABA biosynthesis, altered glutamine transport and the subsequent glutamate/GABA-glutamine cycle efficacy might influence these pathways. Given this potential outcome, the aim of the present study was to investigate whether the expression of the glutamine transporters SAT1, SAT2, SN1 and SN2 would be affected in chronic HE. We verified that mRNA expression of the neuronal glutamine transporters SAT1 and SAT2 was found unaltered in the cerebral cortex of BDL rats. Similarly, no changes were found in the mRNA level for the astrocytic transporter SN1, whereas the gene expression of SN2 was increased by two-fold in animals with chronic HE. However, SN2 protein immuno-reactivity did not correspond with the increase in gene transcription since it remained unaltered. These data indicate that the expression of the glutamine transporter isoforms is unchanged during chronic HE, and thus likely not to participate in the pathological mechanisms related to the imbalance in the GABAergic neurotransmitter system observed in this neurologic condition.
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Affiliation(s)
- Renata Leke
- Experimental Hepatology and Gastroenterology Laboratory, Research Center of Hospital de Clínicas de Porto Alegre, Porto Alegre 90035-903, Brazil; Department of Pathology, University of Miami School of Medicine and Veterans Administration Medical Center, Miami, FL 33101, USA.
| | - Thayssa D C Escobar
- Experimental Hepatology and Gastroenterology Laboratory, Research Center of Hospital de Clínicas de Porto Alegre, Porto Alegre 90035-903, Brazil
| | - Kakulavarapu V Rama Rao
- Department of Pathology, University of Miami School of Medicine and Veterans Administration Medical Center, Miami, FL 33101, USA
| | - Themis Reverbel Silveira
- Experimental Hepatology and Gastroenterology Laboratory, Research Center of Hospital de Clínicas de Porto Alegre, Porto Alegre 90035-903, Brazil; Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Michael D Norenberg
- Department of Pathology, University of Miami School of Medicine and Veterans Administration Medical Center, Miami, FL 33101, USA
| | - Arne Schousboe
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2100, Denmark
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5
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Schousboe A, Waagepetersen HS, Leke R, Bak LK. Effects of hyperammonemia on brain energy metabolism: controversial findings in vivo and in vitro. Metab Brain Dis 2014; 29:913-7. [PMID: 24577633 DOI: 10.1007/s11011-014-9513-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 02/14/2014] [Indexed: 12/21/2022]
Abstract
The literature related to the effects of elevated plasma ammonia levels on brain energy metabolism is abundant, but heterogeneous in terms of the conclusions. Thus, some studies claim that ammonia has a direct, inhibitory effect on energy metabolism whereas others find no such correlation. In this review, we discuss both recent and older literature related to this controversial topic. We find that it has been consistently reported that hepatic encephalopathy and concomitant hyperammonemia lead to reduced cerebral oxygen consumption. However, this may not be directly linked to an effect of ammonia but related to the fact that hepatic encephalopathy is always associated with reduced brain activity, a condition clearly characterized by a decreased CMRO2. Whether this may be related to changes in GABAergic function remains to be elucidated.
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Affiliation(s)
- Arne Schousboe
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen Ø, Denmark
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6
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Leke R, Silveira TR, Escobar TDC, Schousboe A. Expression of Glutamate Decarboxylase (GAD) mRNA in the brain of bile duct ligated rats serving as a model of hepatic encephalopathy. Neurochem Res 2013; 39:605-11. [PMID: 23904086 DOI: 10.1007/s11064-013-1116-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2013] [Revised: 07/17/2013] [Accepted: 07/22/2013] [Indexed: 12/14/2022]
Abstract
Hepatic encephalopathy (HE) is a neurologic disorder that involves different pathophysiological mechanisms, including disturbances in the GABAergic neurotransmitter system. Albeit an overall increase in the level of neurotransmitter GABA has not been found in HE, alterations in GABA receptors and metabolism have been described. Moreover, it has been reported that bile duct ligated (BDL) rats, an animal model for the study of HE, exhibited an altered GABA biosynthesis involving preferentially the tricarboxylic (TCA) cycle. In this context it should be noted that the GABA synthesizing enzyme glutamate decarboxylase (GAD) is expressed in the brain in two isoforms GAD67 and GAD65, GAD65 being related to the synthesis of GABA that occurs via the TCA cycle and coupled to the vesicular pool of the neurotransmitter. The aim of the present study was to investigate whether changes in mRNA expression of GAD67 and GAD65 were related to the altered GABA biosynthesis previously observed. To study this, cerebral cortices and hippocampi were dissected from control and BDL rats, total mRNA was isolated and cDNA was synthesized by reverse transcription reaction. Subsequently samples were analyzed for gene expression of GAD67 and GAD65 by qPCR multiplex assay, using GAPDH as endogenous control. No changes in GAD67 and GAD65 mRNA expression between control and BDL rats either in cerebral cortex or in hippocampus were observed indicating that the HE condition did not lead to changes in GAD mRNA expression. However, other regulatory mechanism might be affecting GAD activity and to clarify this additional studies need to be conducted.
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Affiliation(s)
- Renata Leke
- Experimental Hepatology and Gastroenterology Laboratory, Research Center of Hospital de Clínicas de Porto Alegre, Avenida Ramiro Barcelos, 2350, Porto Alegre, RS, 90035-903, Brazil,
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7
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Leke R, Oliveira DL, Forgiarini LF, Escobar TDC, Hammes TO, Meyer FS, Keiding S, Silveira TR, Schousboe A. Impairment of short term memory in rats with hepatic encephalopathy due to bile duct ligation. Metab Brain Dis 2013; 28:187-92. [PMID: 23111918 DOI: 10.1007/s11011-012-9347-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 10/15/2012] [Indexed: 12/12/2022]
Abstract
Hepatic encephalopathy (HE) arises from acute or chronic liver diseases and leads to cognitive deficits. Different animal models for the study of HE have demonstrated learning and memory impairment and a number of neurotransmitter systems have been proposed to be involved in this. Recently, it was described that bile duct-ligated (BDL) rats exhibited altered spatio-temporal locomotor and exploratory activities and biosynthesis of neurotransmitter GABA in brain cortices. Therefore, the aim of this study was to evaluate cognition in the same animal model. Male adult Wistar rats underwent common bile duct ligation (BDL rats) or manipulation of common bile duct without ligation (control rats). Six weeks after surgery, control and BDL rats underwent object recognition behavioral task. The BDL rats developed chronic liver failure and exhibited a decreased discrimination index for short term memory (STM) when compared to the control group. There was no difference in long term memory (LTM) as well as in total time of exploration in the training, STM and LTM sessions between the BDL and control rats. Therefore, the BDL rats demonstrated impaired STM for recognition memory, which was not due to decreased exploration.
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Affiliation(s)
- Renata Leke
- Experimental Hepatology and Gastroenterology Laboratory, Research Center of Hospital de Clínicas de Porto Alegre, Avenida Ramiro Barcelos, 2350, Porto Alegre, Rio Grande do Sul 90035-903, Brazil.
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Leke R. I206 REQUIREMENTS FOR AN EFFECTIVE FACILITY-BASED MATERNAL DEATH REVIEW (MDR) COMMITTEE: EXPERIENCES OF THE SOCIETY OF GYNECOLOGISTS AND OBSTETRICIANS OF CAMEROON (SOGOC). Int J Gynaecol Obstet 2012. [DOI: 10.1016/s0020-7292(12)60236-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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9
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Leke R, de Oliveira DL, Mussulini BHM, Pereira MS, Kazlauckas V, Mazzini G, Hartmann CR, Silveira TR, Simonsen M, Bak LK, Waagepetersen HS, Keiding S, Schousboe A, Portela LV. Impairment of the organization of locomotor and exploratory behaviors in bile duct-ligated rats. PLoS One 2012; 7:e36322. [PMID: 22586467 PMCID: PMC3346757 DOI: 10.1371/journal.pone.0036322] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 03/30/2012] [Indexed: 12/16/2022] Open
Abstract
Hepatic encephalopathy (HE) arises from acute or chronic liver diseases and leads to several problems, including motor impairment. Animal models of chronic liver disease have extensively investigated the mechanisms of this disease. Impairment of locomotor activity has been described in different rat models. However, these studies are controversial and the majority has primarily analyzed activity parameters. Therefore, the aim of the present study was to evaluate locomotor and exploratory behavior in bile duct-ligated (BDL) rats to explore the spatial and temporal structure of behavior. Adult female Wistar rats underwent common bile duct ligation (BDL rats) or the manipulation of common bile duct without ligation (control rats). Six weeks after surgery, control and BDL rats underwent open-field, plus-maze and foot-fault behavioral tasks. The BDL rats developed chronic liver failure and exhibited a decrease in total distance traveled, increased total immobility time, smaller number of rearings, longer periods in the home base area and decreased percentage of time in the center zone of the arena, when compared to the control rats. Moreover, the performance of the BDL rats was not different from the control rats for the elevated plus-maze and foot-fault tasks. Therefore, the BDL rats demonstrated disturbed spontaneous locomotor and exploratory activities as a consequence of altered spatio-temporal organization of behavior.
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Affiliation(s)
- Renata Leke
- Department of Biochemistry, ICBS, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sol, Brazil.
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Leke R, Bak LK, Iversen P, Sørensen M, Keiding S, Vilstrup H, Ott P, Portela LV, Schousboe A, Waagepetersen HS. Synthesis of neurotransmitter GABA via the neuronal tricarboxylic acid cycle is elevated in rats with liver cirrhosis consistent with a high GABAergic tone in chronic hepatic encephalopathy. J Neurochem 2011; 117:824-32. [PMID: 21395584 DOI: 10.1111/j.1471-4159.2011.07244.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Hepatic encephalopathy (HE) is a neuropsychiatric complication to liver disease. It is known that ammonia plays a role in the pathogenesis of HE and disturbances in the GABAergic system have been related to HE. Synthesis of GABA occurs by decarboxylation of glutamate formed by deamidation of astrocyte-derived glutamine. It is known that a fraction of glutamate is decarboxylated directly to GABA (referred to as the direct pathway) and that a fraction undergoes transamination with formation of alpha-ketoglutarate. The latter fraction is cycled through the neuronal tricarboxylic acid cycle, an energy-generating pathway, prior to being employed for GABA synthesis (the indirect pathway). We have previously shown that ammonia induces an elevation of the neuronal tricarboxylic acid cycle activity. Thus, the aims of the present study were to determine if increased levels of ammonia increase GABA synthesis via the indirect pathway in a rat model of HE induced by bile-duct ligation and in co-cultures of neurons and astrocytes exposed to ammonia. Employing (13) C-labeled precursors and subsequent analysis by mass spectrometry, we demonstrated that more GABA was synthesized via the indirect pathway in bile duct-ligated rats and in co-cultures subjected to elevated ammonia levels. Since the indirect pathway is associated with synthesis of vesicular GABA, this might explain the increased GABAergic tone in HE.
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Affiliation(s)
- Renata Leke
- PET Centre, Department of Medicine V, Aarhus University Hospital, Aarhus, Denmark
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11
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Kazlauckas V, Kalinine E, Leke R, Oses JP, Nunes F, Espinosa J, Mioranzza S, Lulhier F, Portela LV, Porciúncula LO, Lara DR. Distinctive effects of unpredictable subchronic stress on memory, serum corticosterone and hippocampal BDNF levels in high and low exploratory mice. Behav Brain Res 2010; 218:80-6. [PMID: 21108973 DOI: 10.1016/j.bbr.2010.11.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Revised: 11/11/2010] [Accepted: 11/12/2010] [Indexed: 01/19/2023]
Abstract
Stress affects learning and memory processes and sensitivity to stress greatly varies between individuals. We studied behavioral and neurobiological effects of unpredictable subchronic stress (USCS) in two behavioral extremes of mice from the same strain (CF1) selected by their exploratory behavior of the central arena of an open field. The top and bottom 25% explorers were classified as low exploratory (LE) and high exploratory (HE) mice, respectively. The open field task, the novel object recognition task (NOR), sucrose intake and tail suspension task were evaluated in LE and HE groups exposed to USCS for two weeks or control conditions. Also serum corticosterone and hippocampal BDNF and S100B levels were analyzed. Both stressed groups exhibited less exploratory activity when submitted to USCS, but their difference in exploratory behavior remained. This short stress protocol did not induce changes in sucrose intake or immobility in the tail suspension task. Also, LE mice exhibited impaired NOR performance after USCS, whereas HE mice changed their pattern of exploration towards less exploration of the familiar object. HE had lower corticosterone levels than LE mice, but corticosterone levels increased after stress only in HE mice. Hippocampal BDNF in LE was lower than in HE but decreased after USCS only in HE mice, whereas S100B levels were not different between groups and did not change with USCS. In conclusion, our results suggest that individual differences in exploratory behavior in rodents from the same strain influence cognitive and biochemical response to stress.
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Affiliation(s)
- Vanessa Kazlauckas
- Programa de Pós-Graduação em Ciências Biológicas/Bioquímica, Universidade Federal do Rio Grande do Sul, Instituto de Ciências Básicas da Saúde, Departamento de Bioquímica, Porto Alegre/RS, 90035-003, Brazil.
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12
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Leke R, Bak LK, Anker M, Melø TM, Sørensen M, Keiding S, Vilstrup H, Ott P, Portela LV, Sonnewald U, Schousboe A, Waagepetersen HS. Detoxification of ammonia in mouse cortical GABAergic cell cultures increases neuronal oxidative metabolism and reveals an emerging role for release of glucose-derived alanine. Neurotox Res 2010; 19:496-510. [PMID: 20480276 DOI: 10.1007/s12640-010-9198-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 03/22/2010] [Accepted: 05/03/2010] [Indexed: 12/24/2022]
Abstract
Cerebral hyperammonemia is believed to play a pivotal role in the development of hepatic encephalopathy (HE), a debilitating condition arising due to acute or chronic liver disease. In the brain, ammonia is thought to be detoxified via the activity of glutamine synthetase, an astrocytic enzyme. Moreover, it has been suggested that cerebral tricarboxylic acid (TCA) cycle metabolism is inhibited and glycolysis enhanced during hyperammonemia. The aim of this study was to characterize the ammonia-detoxifying mechanisms as well as the effects of ammonia on energy-generating metabolic pathways in a mouse neuronal-astrocytic co-culture model of the GABAergic system. We found that 5 mM ammonium chloride affected energy metabolism by increasing the neuronal TCA cycle activity and switching the astrocytic TCA cycle toward synthesis of substrate for glutamine synthesis. Furthermore, ammonia exposure enhanced the synthesis and release of alanine. Collectively, our results demonstrate that (1) formation of glutamine is seminal for detoxification of ammonia; (2) neuronal oxidative metabolism is increased in the presence of ammonia; and (3) synthesis and release of alanine is likely to be important for ammonia detoxification as a supplement to formation of glutamine.
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Affiliation(s)
- Renata Leke
- Department of Biochemistry, ICBS, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
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13
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Leke R, Bak LK, Schousboe A, Waagepetersen HS. Erratum to: Demonstration of Neuron-Glia Transfer of Precursors for Gaba Biosynthesis in a Co-Culture System of Dissociated Mouse Cerebral Cortex. Neurochem Res 2009. [DOI: 10.1007/s11064-009-0062-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Tchente Nguefack C, Fogaing A, Tejiokem M, Nana Njotang P, Mbu R, Leke R. Évolution de la grossesse sur un utérus fibromyomateux chez un groupe de femmes camerounaises. ACTA ACUST UNITED AC 2009; 38:493-9. [DOI: 10.1016/j.jgyn.2009.04.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Revised: 04/05/2009] [Accepted: 04/17/2009] [Indexed: 10/20/2022]
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15
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Hofmann KW, Schuh AFS, Saute J, Townsend R, Fricke D, Leke R, Souza DO, Portela LV, Chaves MLF, Rieder CRM. Interleukin-6 serum levels in patients with Parkinson's disease. Neurochem Res 2009; 34:1401-4. [PMID: 19214748 DOI: 10.1007/s11064-009-9921-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2009] [Indexed: 10/21/2022]
Abstract
Several lines of evidence suggest that neuroimmune mechanisms may be involved in the neurodegenerative process of Parkinson's disease (PD). Interleukin-6 (IL-6) is increased in the nigrostriatal region and in the cerebrospinal fluid of patients with PD. IL-6 serum level was evaluated in PD patients. The effects of levodopa treatment and disease severity on IL-6 were also studied. The IL-6 levels were similar between PD patients (treated and not treated) and controls. However, there was a negative correlation of IL-6 levels and the activities of daily living scale (P < 0.05), indicating that patients with more severe disease have higher levels of this cytokine. No correlation involving levodopa treatment and IL-6 serum level was found. The results suggest that only marginal effects of IL-6 occur on the peripheral immune system, and that the role of IL-6 and others neuroimmune factors needs to be well elucidated on PD.
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Affiliation(s)
- Kerly Wollmeister Hofmann
- Serviço de Neurologia, Hospital de Clínicas de Porto Alegre, Rua Ramiro Barcelos 2350, 90035-003 Porto Alegre, RS, Brazil
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16
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Ponka R, Fokou E, Rock E, Fotso M, Souopgui J, Leke R, Mbiapo Tchouanguep F. Composition en caroténoïdes, vitamines A et E des aliments consommés dans une zone de paludisme endémique au Cameroun (Ngali II). ACTA ACUST UNITED AC 2007. [DOI: 10.3166/sda.27.202-213] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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17
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Oses JP, Viola GG, de Paula Cognato G, Júnior VHC, Hansel G, Böhmer AE, Leke R, Bruno AN, Bonan CD, Bogo MR, Portela LV, Souza DO, Sarkis JJF. Pentylenetetrazol kindling alters adenine and guanine nucleotide catabolism in rat hippocampal slices and cerebrospinal fluid. Epilepsy Res 2007; 75:104-11. [PMID: 17544258 DOI: 10.1016/j.eplepsyres.2007.04.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2007] [Revised: 04/18/2007] [Accepted: 04/19/2007] [Indexed: 11/21/2022]
Abstract
Pentylenetetrazol (PTZ) is commonly used as a convulsant drug. The enhanced seizure susceptibility induced by kindling is probably attributable to plastic changes in the synaptic efficacy. Adenosine and guanosine act both as important neuromodulators and neuroprotectors with mostly inhibitory effects on neuronal activity. Adenosine and guanosine can be released per se or generated from released nucleotides (ATP, ADP, AMP, GTP, GDP, and GMP) that are metabolized and rapidly converted to adenosine and guanosine. The aim of this study was to evaluate nucleotide hydrolysis by ecto- and soluble nucleotidases (hippocampal slices and CSF, respectively) after PTZ-kindling (stages 3, 4, or 5 seizures) or saline treatment in rats. Additionally, the levels of purines in rat cerebrospinal fluid (CSF), as well as ecto-NTPDases (1, 2, 3, 5, 6 and 8) and ecto- 5'-nucleotidase expression were determined. Ecto-enzyme assays demonstrated that ATP, AMP, GDP, and GMP hydrolysis enhanced when compared with controls. In addition, there was an increase of ADP, GDP, and GMP hydrolysis by soluble nucleotidases in PTZ-kindling rats compared to control group. The HPLC analysis showed a marked increase in PTZ-kindled CSF concentrations of GTP, ADP, and uric acid, but GDP, AMP, and hypoxanthine concentrations were decreased. Such alterations indicate that the modulatory role of purines in CNS could be affected by PTZ-kindling. However, the physiological significance of these findings remains to be elucidated.
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Affiliation(s)
- Jean Pierre Oses
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul. Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003 Porto Alegre, RS, Brazil.
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18
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Machado-Vieira R, Dietrich MO, Leke R, Cereser VH, Zanatto V, Kapczinski F, Souza DO, Portela LV, Gentil V. Decreased plasma brain derived neurotrophic factor levels in unmedicated bipolar patients during manic episode. Biol Psychiatry 2007; 61:142-4. [PMID: 16893527 DOI: 10.1016/j.biopsych.2006.03.070] [Citation(s) in RCA: 149] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2005] [Revised: 03/17/2006] [Accepted: 03/22/2006] [Indexed: 11/17/2022]
Abstract
BACKGROUND Bipolar disorder (BD) has been increasingly associated with abnormalities in neuroplasticity and cellular resilience. Brain Derived Neurotrophic Factor (BDNF) gene has been considered an important candidate marker for the development of bipolar disorder and this neurotrophin seems involved in intracellular pathways modulated by mood stabilizers. Also, previous studies demonstrated a role for BDNF in the pathophysiology and clinical presentation of mood disorders. METHODS We investigated whether BDNF levels are altered during mania. Sixty subjects (14 M and 46 F) were selected and included in the study. Thirty patients meeting SCID-I criteria for manic episode were age and gender matched with thirty healthy controls. Young Mania Rating Scale (YMRS) evaluated the severity of manic episode and its possible association with the neurotrophin levels. RESULTS Mean BDNF levels were significantly decreased in drug free/naive (224.8 +/- 76.5 pg/ml) compared to healthy controls (318.5 +/- 114.2), p < .001]. Severity of the manic episode presented a significant negatively correlation to plasma BDNF levels (r= .78; p < .001; Pearson test). CONCLUSIONS Overall, these results suggest that the decreased plasma BDNF levels may be directly associated with the pathophysiology and severity of manic symptoms in BD. Further studies are necessary to clarify the role of BDNF as a putative biological marker in BD.
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Affiliation(s)
- Rodrigo Machado-Vieira
- Mood Disorders Program, Fundação Faculdade Federal Ciências Medicas de Porto Alegre, Bipolar Disorder Research Program, Espírita Hospital of Porto Alegre, Porto Alegre, Brazil
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19
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Grillo RW, Ottoni GL, Leke R, Souza DO, Portela LV, Lara DR. Reduced serum BDNF levels in schizophrenic patients on clozapine or typical antipsychotics. J Psychiatr Res 2007; 41:31-5. [PMID: 16546213 DOI: 10.1016/j.jpsychires.2006.01.005] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2005] [Revised: 12/16/2005] [Accepted: 01/12/2006] [Indexed: 12/23/2022]
Abstract
Neurotrophic factors regulate neuronal development and synaptic plasticity, possibly playing a role in the pathophysiology of schizophrenia and other psychiatric disorders. Decreased brain-derived neurotrophic factor (BDNF) levels have been found in brains and in the serum of schizophrenic patients, but results are inconsistent. Also, clozapine may upregulate brain BDNF expression. In the present study, we assessed serum BDNF immunoreactivity in 44 schizophrenic patients (20 on clozapine and 24 on typical antipsychotics) and in 25 healthy volunteers. Serum BDNF levels were measured using an enzyme immunoassay. Healthy controls showed significantly higher levels of BDNF compared to the whole group of schizophrenic patients (p<0.001) as well as to the subgroups on typical antipsychotics and clozapine (p<0.001). Serum BDNF values for controls were 168.8+/-26.3pg/ml, for the clozapine group were 125.4+/-44.5pg/ml and for the group on typicals were 101.3+/-51.6pg/ml. BDNF values from patients on clozapine were non-significantly higher than values from patients on typical antipsychotics (p=0.09). Serum BDNF was strongly and positively correlated with clozapine dose (r=0.643; p=0.002) but not with other demographic characteristics. These results reinforce previous findings of reduced serum BDNF levels in schizophrenic patients and suggest a differential effect of clozapine compared to typical antipsychotics on such levels.
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20
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Leke R, Oliveira DL, Schmidt AP, Avila TT, Jorge RS, Fischer A, Wofchuk S, Souza DO, Portela LV. Methotrexate induces seizure and decreases glutamate uptake in brain slices: Prevention by ionotropic glutamate receptors antagonists and adenosine. Life Sci 2006; 80:1-8. [PMID: 16962142 DOI: 10.1016/j.lfs.2006.08.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Revised: 05/21/2006] [Accepted: 08/14/2006] [Indexed: 12/20/2022]
Abstract
Methotrexate (MTX)-induced neurotoxicity may occur after intrathecal or systemic administration at low, intermediate and high doses for the treatment of malignant or inflammatory diseases. The mechanisms of MTX neurotoxicity are not totally understood, and appear to be multifactorial. In this study we characterized a model of MTX-induced seizures in mice to evaluate the convulsive and toxic MTX properties. Additionally, the effect of MTX-induced seizures on the activity of glutamate transporters, as well as the anticonvulsant role of MK-801, DNQX and adenosine on glutamate uptake in brain slices was investigated . MTX induced tonic-clonic seizures in approximately 95% of animals and pre-treatment with MK-801, DNQX and adenosine prevented seizure in 80%, 62% and 50% of animals, respectively. Moreover, MTX leads 59% of mice to death, which was prevented in 100% and 94% when animals received MK-801 and DNQX, respectively. Glutamate uptake decreased by 20% to 30% in cortical slices after MTX-induced seizures. Interestingly, when seizures were prevented by MK-801, DNQX or adenosine, glutamate uptake activity remained at the same level as the control group. Thus, our results demonstrate the involvement of the glutamatergic system in MTX-induced seizures.
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Affiliation(s)
- R Leke
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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21
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Busnello JV, Leke R, Oses JP, Feier G, Bruch R, Quevedo J, Kapczinski F, Souza DO, Cruz Portela LV. Acute and chronic electroconvulsive shock in rats: Effects on peripheral markers of neuronal injury and glial activity. Life Sci 2006; 78:3013-7. [PMID: 16413036 DOI: 10.1016/j.lfs.2005.11.028] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2005] [Revised: 11/01/2005] [Accepted: 11/29/2005] [Indexed: 11/27/2022]
Abstract
Electroconvulsive therapy is considered one of the most effective treatments of major depression, but controversy still exists on whether it may be brain damaging. The aim of this work was to evaluate the cerebrospinal fluid (CSF) levels of neuron specific enolase (NSE), protein S100B and lactate of rats submitted to acute and chronic models of ECS. Rats were submitted to either one shock (acute) or a series of eight shocks, applied one at every 48 h (chronic). CSF samples were collected at 0, 3, 6, 12, 24, 48 and 72 h after the shock in the acute model and at these same time intervals after the last shock in the chronic model. Both models did not produce significant alterations in the levels of NSE. S100B levels were significantly increased at 6 h in the chronic model (p<0.0001). There was a significant increase in the levels of lactate at 0 h in both models (p<0.001). These results support the proposition that ECS does not produce neural damage, and suggest that the alterations in the levels of S100B and lactate may reflect an astrocytic activity of a protective nature.
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Affiliation(s)
- João Vicente Busnello
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul. Ramiro Barcelos, 2600-Anexo 90035-003 Porto Alegre, RS, Brazil.
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22
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Oses JP, Leke R, Portela LV, Lara DR, Schmidt AP, Casali EA, Wofchuk S, Souza DO, Sarkis JJF. Biochemical brain markers and purinergic parameters in rat CSF after seizure induced by pentylenetetrazol. Brain Res Bull 2005; 64:237-42. [PMID: 15464860 DOI: 10.1016/j.brainresbull.2004.07.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2004] [Revised: 07/13/2004] [Accepted: 07/19/2004] [Indexed: 11/19/2022]
Abstract
Cellular and molecular mechanisms involved in the generation of seizures and the magnitude of neural cells injury are not fully understood. We evaluated astrocyte and/or neuronal injury in rats in the pentylenetetrazol model of acute seizures by measuring S100B and NSE levels in cerebrospinal fluid. Additionally, we determined ADP and GDP hydrolysis by soluble nucleoside triphosphate diphosphohydrolase in the cerebrospinal fluid, and the concentration of nucleosides adenosine, inosine and guanosine as putative markers of brain injury. After pentylenetetrazol-induced seizures: (i) S100B values increased from 10 to 30 min, returning to control levels at 24 h; NSE levels presented a biphasic increase: an increase at 10 to 30 min returning to control levels, and again at 240 min followed by a decline at 24 h; (ii) nucleotidase activities increased from 10 min, returning to control levels at 240 min; (iii) guanosine and inosine levels increased exclusively after 30 min. In summary, this study showed biochemical changes in the cerebrospinal fluid occurring after seizures induced by pentylenetetrazol. Such events may have a modulating effect upon seizure expression, particularly nucleoside triphosphate diphosphohydrolase activities and nucleoside concentrations, but are nevertheless followed by neural death as evidenced by the increase in NSE and S100B levels.
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Affiliation(s)
- Jean Pierre Oses
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600 anexo, 90035-003, Porto Alegre, RS, Brazil
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23
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Thonneau P, Leke R, Goyaux N, Matsuda T. P12-8 Incidence de la grossesse extra-utérine en Afrique : résultats d’une étude en population générale menée à Yaoundé, Cameroun. Rev Epidemiol Sante Publique 2004. [DOI: 10.1016/s0398-7620(04)99355-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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24
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O'Neil-Dunne I, Achur RN, Agbor-Enoh ST, Valiyaveettil M, Naik RS, Ockenhouse CF, Zhou A, Megnekou R, Leke R, Taylor DW, Gowda DC. Gravidity-dependent production of antibodies that inhibit binding of Plasmodium falciparum-infected erythrocytes to placental chondroitin sulfate proteoglycan during pregnancy. Infect Immun 2001; 69:7487-92. [PMID: 11705924 PMCID: PMC98838 DOI: 10.1128/iai.69.12.7487-7492.2001] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During pregnancy, Plasmodium falciparum-infected erythrocytes sequester in the placenta by adhering to chondroitin 4-sulfate, creating a risk factor for both the mother and the fetus. The primigravidae are at higher risk for placental malaria than the multigravidae. This difference in susceptibility has been attributed to the lack of antibodies that block the adhesion of infected erythrocytes to placental chondroitin 4-sulfate in primigravid women. However, recent results show that many primigravidae at term have antibody levels similar to those of multigravidae, and thus the significance of antiadhesion antibodies in providing protection against malaria during pregnancy remains unclear. In this study, we analyzed plasma samples from women of various gravidities at different gestational stages for antiadhesion antibodies. The majority of women, regardless of gravidity, had similar levels of antibodies at term. Most primigravidae had low levels of or no antiadhesion antibodies prior to ~20 weeks of pregnancy and then produced antibodies. Multigravidae also lacked antibodies until ~12 weeks of pregnancy, but thereafter they efficiently produced antibodies. In pregnant women who had placental infection at term, higher levels of antiadhesion antibodies correlated with lower levels of placental parasitemia. The difference in kinetics of antibody production between primigravidae and multigravidae correlated with the prevalence of malaria in these groups, suggesting that antibodies are produced during pregnancy in response to placental infection. The early onset of efficient antibody response in multigravidae and the delayed production to antibodies in primigravidae appear to account for the gravidity-dependent differential susceptibilities of pregnant women to placental malaria.
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Affiliation(s)
- I O'Neil-Dunne
- Department of Biochemistry and Molecular Biology, Georgetown University Medical Center, Washington, DC 20007, USA
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25
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Staalsoe T, Megnekou R, Fievét N, Ricke CH, Zornig HD, Leke R, Taylor DW, Deloron P, Hviid L. Acquisition and decay of antibodies to pregnancy-associated variant antigens on the surface of Plasmodium falciparum-infected erythrocytes that protect against placental parasitemia. J Infect Dis 2001; 184:618-26. [PMID: 11494167 DOI: 10.1086/322809] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2001] [Revised: 04/03/2001] [Indexed: 11/04/2022] Open
Abstract
Otherwise clinically immune women in areas endemic for malaria are highly susceptible to Plasmodium falciparum malaria during their first pregnancy. Pregnancy-associated malaria (PAM) is characterized by placental accumulation of infected erythrocytes that adhere to chondroitin sulfate A (CSA). Susceptibility to PAM decreases with increasing parity, apparently due to acquisition of antibodies directed against the variant surface antigens (VSAs) that mediate the adhesion to CSA (VSA(CSA)). This study found that levels of VSA(CSA)-specific antibodies depend on endemicity, that anti-VSA(CSA) IgG is acquired during gestation week 20, and that plasma levels of the antibodies decline during the postpartum period. There is evidence that VSA(CSA)-specific antibodies are linked to placental infection and that high antibody levels contribute to the control of placental infection by inhibiting parasite adhesion to CSA. Data suggest that VSA(CSA) is a target for vaccination against PAM.
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Affiliation(s)
- T Staalsoe
- Centre for Medical Parasitology, Copenhagen University Hospital (Rigshospitalet) and Institute for Medical Microbiology and Immunology, University of Copenhagen, 2200 Copenhagen N, Denmark.
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26
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Abstract
HLA-DRB1, -DQA1 and -DQB1 allele frequencies were determined by high-resolution polymerase chain reaction using sequence-specific oligonucleotide probes (PCR-SSOP) and/or DNA sequencing in 126 healthy individuals in Cameroon. Eighteen DRB1, 11 DQA1, and 18 DQB1 alleles were observed. The most common alleles at each locus were DRB1*1503 (29%), DRB1*1301 (13%); DQA1*0102 (38%), DQA1*0302 (11%), DQA1*0401 (11%); and DQB1*0602 (31%), DQB1*0301 (13%), DQB1*0501 (12%). Forty-four different haplotypes were identified including 12 novel haplotypes demonstrating the HLA class II diversity resulting from allele combinations in this population. A single predominant DRB1*1503-DQA1*0102-DQB1*0602 haplotype was observed with a frequency of 27%. In summary, this study of HLA class II polymorphism in Cameroon demonstrates the extent of diversity in this population.
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Affiliation(s)
- N Pimtanothai
- Department of Microbiology and Immunology, Georgetown University Medical Center, 3900 Reservoir Road NW, Washington, D.C. 20007, USA
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Goyaux N, Alihonou E, Diadhiou F, Leke R, Thonneau PF. Complications of induced abortion and miscarriage in three African countries: a hospital-based study among WHO collaborating centers. Acta Obstet Gynecol Scand 2001; 80:568-73. [PMID: 11380296] [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: 02/20/2023]
Abstract
OBJECTIVE The aim of this study was to describe two of the outcomes of pregnancy, induced abortion and miscarriage, in three African countries. Major maternal risk factors were also evaluated. METHODS The study was prospective and based on the medical files of all 1,957 women admitted to participating health care structures. RESULTS Overall, 988 women were admitted for complications of miscarriage, and 969 for complications of induced abortion. Gestational age was lower in women with miscarriages (p<0.002). The level of use of contraceptive methods ((p<0.003) and educational level ((p<0.005) were lower in women who had had an induced abortion. In our study, 26 maternal deaths were recorded, 22 of which were associated with induced abortion. Infection was the most important risk factor for death (OR=4.8; 1.9-12.4). CONCLUSION Maternal deaths related to abortion complications often occurred shortly after hospital admission and with signs of sepsis. This demonstrates the importance of effective emergency services. Unfortunately, hospital-based studies alone cannot assess all maternal death risk factors, especially those for maternal death related to induced abortion complications. It is therefore important to determine what happened to the woman before hospital admission and during her stay in hospital. Combinations of qualitative and quantitative methods could be used to increase our understanding of this problem and to help us to solve it.
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Affiliation(s)
- N Goyaux
- Human Fertility Research Group, Toulouse, France
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Quakyi IA, Ndoutse L, Ngu J, Lohoue J, Fogako J, Befidi-Mengue R, Harun LT, Eno A, Walker-Abbey A, Folefack A, Alake G, Taylor DW, Tchinda V, Megnekou R, Ndountse L, Tietche F, Wansi E, Leke RG, Titanji V, Leke R, Sama G, Manga L, Johnson AH, Mvondo JL, Nyonglema P, Djokam R, Bomba-Nkolo C, Tsafack M, Hickey MA, Bigoga J, Bomba-Nkolo D, Kouontchou S, Meli J, Njeungue E, Metenou S, Same-Ekobo A. The epidemiology of Plasmodium falciparum malaria in two Cameroonian villages: Simbok and Etoa. Am J Trop Med Hyg 2000. [DOI: 10.4269/ajtmh.2000.63.222] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Quakyi IA, Leke RG, Befidi-Mengue R, Tsafack M, Bomba-Nkolo D, Manga L, Tchinda V, Njeungue E, Kouontchou S, Fogako J, Nyonglema P, Harun LT, Djokam R, Sama G, Eno A, Megnekou R, Metenou S, Ndountse L, Same-Ekobo A, Alake G, Meli J, Ngu J, Tietche F, Lohoue J, Mvondo JL, Wansi E, Leke R, Folefack A, Bigoga J, Bomba-Nkolo C, Titanji V, Walker-Abbey A, Hickey MA, Johnson AH, Taylor DW, Ndoutse L. The epidemiology of Plasmodium falciparum malaria in two Cameroonian villages: Simbok and Etoa. Am J Trop Med Hyg 2000; 63:222-30. [PMID: 11421368] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
In support of ongoing immunologic studies on immunity to Plasmodium falciparum, demographic, entomologic, parasitologic, and clinical studies were conducted in two Cameroonian villages located 3 km apart. Simbok (population = 907) has pools of water present year round that provide breeding sites for Anopheles gambiae, whereas Etoa (population = 485) has swampy areas that dry up annually in which A. funestus breed. Results showed that individuals in Simbok receive an estimated 1.9 and 1.2 infectious bites per night in the wet and dry season, respectively, whereas individuals in Etoa receive 2.4 and 0.4 infectious bites per night, respectively. Although transmission patterns differ, the rate of acquisition of immunity to malaria appears to be similar in both villages. A prevalence of 50-75% was found in children < 10 years old, variable levels in children 11-15 years old, and 31% in adults. Thus, as reported in other parts of Africa, individuals exposed to continuous transmission of P. falciparum slowly acquired significant, but not complete, immunity.
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Affiliation(s)
- I A Quakyi
- Department of Biology, Reiss Science Center, Georgetown University, Washington, District of Columbia 20057, USA
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Johnson A, Leke R, Harun L, Ginsberg C, Ngogang J, Stowers A, Saul A, Quakyi IA. Interaction of HLA and age on levels of antibody to Plasmodium falciparum rhoptry-associated proteins 1 and 2. Infect Immun 2000; 68:2231-6. [PMID: 10722624 PMCID: PMC97408 DOI: 10.1128/iai.68.4.2231-2236.2000] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Plasmodium falciparum rhoptry-associated proteins 1 and 2 (RAP1 and RAP2) are candidate antigens for a subunit malaria vaccine. The design of the study, which looks at the acquisition of immunity to malaria from childhood to old age, has allowed us to document the interaction of HLA and age on levels of antibody to specific malarial antigens. Antibodies reach maximum levels to RAP1 after the age of 15 but to RAP2 only after the age of 30. The effect of HLA-DRB1 and -DQB1 and age on levels of antibody to rRAP1 and rRAP2 was analyzed with a multiple regression model in which all HLA alleles and age were independent variables. DQB1*0301 and -*03032 showed an age-dependent association with levels of antibody to rRAP1, being significant in children 5 to 15 years (P < 0.001) but not in individuals over 15 years of age. DRB1*03011 showed an age-dependent association with antibody levels to rRAP2; however, this association was in adults over the age of 30 years (P < 0.01) but not in individuals under the age of 30 years. No associations were detected between DRB1 alleles and RAP1 antibody levels or between DQB1 alleles and RAP2 antibody levels. Thus, not only the HLA allele but also the age at which an interaction is manifested varies for different malarial antigens. The interaction may influence either the rate of acquisition of antibody or the final level of antibody acquired by adults.
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Affiliation(s)
- A Johnson
- Pediatrics, Georgetown University, Washington, D.C., USA.
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Nkuo-Akenji T, Deas J, Leke R, Ngu J. Patterns of antibody levels to the 96 tR recombinant protein of Plasmodium falciparum in children over a six-month period. J Parasitol 1995; 81:195-9. [PMID: 7707194] [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: 01/26/2023] Open
Abstract
Several Plasmodium falciparum asexual stage antigens have been reported as possible candidate antigens for vaccines against malaria. One such is the 96-kDa antigen. We used the 96 tR recombinant protein to determine the levels of antibodies to this protein over a 6-mo period in children 4 mo to 15 yr old, who make up the population at risk in Cameroon. The mean enzyme-linked immunosorbent assay (ELISA) on 83 children at the start of the study in June was 0.270, with 13% of these children having ELISA values considered to be positive (> or = 0.36). In the follow-up study in early December, the mean ELISA was 0.320 with 20% of the children having positive values. In the period between June and December, 85% of the children who returned for follow-up had had 1 or more attacks of malaria. The mean ELISA values of this latter group had increased from 0.235 in June to 0.318 in December, with 6% of the children in June having positive values compared with 18% in December. These findings reinforce our evidence from a previous study that reactivity to the 96-kDa antigen is related to adequate exposure or repeated infection.
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Affiliation(s)
- T Nkuo-Akenji
- Department of Life Sciences, Faculty of Science, University of Buea, Cameroon
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Nkuo-Akenji T, Deas J, Leke R, Ngu J. Patterns of Antibody Levels to the 96 tR Recombinant Protein of Plasmodium falciparum in Children over a Six-Month Period. J Parasitol 1995. [DOI: 10.2307/3283919] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Grathwohl J, Ndumbe P, Leke R, Uy A, Gerlich WH, Repp R. [Perinatal hepatitis B virus transmission]. Monatsschr Kinderheilkd 1992; 140:366-8. [PMID: 1640950] [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: 12/28/2022]
Abstract
Using the highly sensitive Polymerase chain reaction (PCR) hepatitis B virus (HBV) DNA has already been detected in many patients negative for all other serological HBV markers [12]. But yet, the relevance of these findings as a marker of infectivity has not been determined. We therefore have used the PCR to examine the perinatal route of HBV transmission by testing sera from 109 mother-child pairs in Yaoundé, Cameroon. HBV-DNA was detected in 25 (23%) of the mother's sera from which only 5 were positive for HBsAg. At the age of 6 months only one baby out of 25 who could be retested had become positive for HBV-DNA, HBsAg, and HBeAg. Low serum HBV-DNA levels which are still detectable by the PCR therefore seem not to be associated with a high risk of perinatal HBV transmission.
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Mbakop A, Leke R, Tedong F, Ngu JL. [Subpopulations of lymphocytes in onchocercal nodules]. Pathol Biol (Paris) 1989; 37:259-61. [PMID: 2660078] [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: 01/02/2023]
Abstract
Fourty onchocercal nodules were taken from patients living in forest areas where onchocerciasis is highly endemic, in order to identify the various types of lymphocytes present in these nodules. For this purpose, each nodule was submitted to two histological procedures: one after fixation in formalin of part of the nodule and hematoxylin-eosin stain; the other after freezing part of the nodule in liquid nitrogen, cryostat cutting and staining by immuno-peroxidase method using avidin-biotin and the following monoclonal antibodies: Pan B, OK T3, OK T4 and OK T8. Fifty-five of the 40 nodules show lymphocytes. All the 25 nodules with lymphocytes present T-lymphocytes. Only 20 of these 25 nodules have B lymphocytes and therefore only 20 nodules with lymphocytes have both T and B lymphocytes. Of the 25 nodules with T lymphocytes: 19 present T4 lymphocytes, 25 show T8 lymphocytes and therefore 19 have both T4 and T8 lymphocytes. These results are analysed and discussed in this study which notices that there is an intense cellular and humoral immune reaction in onchocercal nodules, an insufficient reaction as parasitic antigens persist and are not destroyed.
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Affiliation(s)
- A Mbakop
- Département de Pathologie, Centre Universitaire des Sciences de la Santé, Yaounde, Cameroun
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Ngu JL, Chatelanat F, Leke R, Ndumbe P, Youmbissi J. Nephropathy in Cameroon: evidence for filarial derived immune-complex pathogenesis in some cases. Clin Nephrol 1985; 24:128-34. [PMID: 3862488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
This study was carried out in two parts. Part 1 consisted of an epidemiological survey of 1011 subjects aged 3-65 yrs from 2 adjoining villages hyper-endemic for Onchocerciasis and 890 subjects in a control area, relatively free from this infection but otherwise with a similar parasitological profile. There was a significantly higher prevalence of proteinuria in subjects from the onchocercal zone than in controls (observed difference greater than 5 1/2 times its standard error). Part 2 comprised detailed investigations, including renal biopsy, of 63 consecutive patients admitted into hospital with severe proteinuria and/or renal failure from a caption area extending into the onchocercal zone. There were a variety of causative factors, but in 9 cases filarial antigen was demonstrable in the immune-complex deposits in the kidney. A plenum of renal histopathological changes were seen in patients with onchocerciasis. The significance of these findings is discussed.
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Leke R, Viens P, Davies AJ. Interaction between Plasmodium chabaudi and C57Bl mice with particular reference to the immune response. Clin Exp Immunol 1981; 45:627-32. [PMID: 7337965 PMCID: PMC1537419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The parasitaemia consequent upon infection of normal, T cell-deprived, or nude mice with a strain of Plasmodium chabaudi was studied. In normal mice three waves of parasitaemia of successively diminishing magnitude were observed, the infected animals becoming aparasitaemic within 45 days. In most T cell-deprived and nude mice a sustained cyclicity of parasitaemia was observed. Slight evidence was adduced of increase in virulence of the parasite with increasing time of infection in deprived mice. No positive evidence could be obtained for modulation of antigenicity of the parasite although this is suspected to be present. The results seem to be in conflict with the notion that the transient diminishing cyclicity of parasitaemia observed in normal mice is due to suppression of the parasite by the host. In the absence of what could be regarded as part of the host defence mechanism the cyclicity far from disappearing was exaggerated and prolonged.
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Ngu JL, Ndumbe PM, Titanji V, Leke R. A diagnostic skin test for Onchocerca volvulus infection. Tropenmed Parasitol 1981; 32:165-70. [PMID: 6808726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Onchocerca supernatant (OS) was prepared by a technique permitting live microfilariae to migrate from nodule tissue through agar gel into sterile Hanks balanced salt/Penicillin-Streptomycin solution where they metabolized. The OS, after dialysis, was passed through Seitz viral filter and either concentrated or lyophilized. Using rabbit antiserum in immunodiffusion and immunoelectrophoresis tests, microfilariae proteins and also human protein were detected in out OS. No common antigens were found between this and somatic extracts of Loa loa, O. gutturosa, O. volvulus, L. carinii, D. immittis and A. lumbricoides. 125I labelled OS was purified by passage through protein A column and then through immunosorbent column of horse anti-human serum linked to CNB-activated sepharose 4B. Autoradiography, after sodium dodecyl sulphate polyacylamide slab gel eletrophoresis of purified OS, showed 10 protein bands in the molecular range 10,000 to 125,000. Skin prick tests with OS, shown not to be contaminated with Hepatitis B antigens, elicited immediate hypersensitivity reaction. Using our criteria, positive reactions were seen in 81% of proven onchocerca cases and only occasionally in Loasis 4.5%, ascaridiasis 13.5% or healthy controls 2.4%. The poor skin reactivity to OS in loasis was not due to immunosuppression as these patients, when also infested with ascaris, reacted just as well as onchocerca patients with ascaris to skin prick test using somatic extracts of ascaris.
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Duchesne C, Leke R. Bromocriptine mesylate for prevention of postpartum lactation. Obstet Gynecol 1981; 57:464-7. [PMID: 7243095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The efficacy and safety of bromocriptine mesylate in preventing postpartum breast engorgement and milk secretion were evaluated in 420 normal puerperal women. The usual dose was 2.5 mg twice a day for 14 days. Complete inhibition of the target symptoms was obtained in 97% (409 of 420) of the women after 5 days of therapy. Of 370 women who completed 14 days of therapy, 73.5% (272) were completely symptom free, and the remainder showed only grade I or grade II breast engorgement and secretion. Side effects, primarily nausea, vomiting, and dizziness, were experienced by 3% of the women, and 7% reported rebound engorgement and secretion. It was concluded that bromocriptine is safe and efficacious for the stated indication. Moreover, bromocriptine's apparent lack of thromboembolic complications and low incidence of rebound effects suggest possible advantages over other pharmacologic preparations, ie, estrogen-containing drugs, currently used to prevent postpartum lactation.
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Ngu JL, Mate A, Leke R, Titanji V. Proteinuria associated with diethylcarbamazine. Lancet 1980; 1:710. [PMID: 6103121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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