1
|
Thiamine deficiency in rats affects thiamine metabolism possibly through the formation of oxidized thiamine pyrophosphate. Biochim Biophys Acta Gen Subj 2021; 1865:129980. [PMID: 34390792 DOI: 10.1016/j.bbagen.2021.129980] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 07/16/2021] [Accepted: 08/03/2021] [Indexed: 12/19/2022]
Abstract
BACKGROUND Thiamine deficiency (TD) has a number of features in common with the neurodegenerative diseases development and close relationship between TD and oxidative stress (OS) has been repeatedly reported in the literature. The aim of this study is to understand how alimentary TD, accompanied by OS, affects the expression and level of two thiamine metabolism proteins in rat brain, namely, thiamine transporter 1 (THTR1) and thiamine pyrophosphokinase (TPK1), and what factors are responsible for the observed changes. METHODS The effects of OS caused by TD on the THTR1and TPK1 expression in rat cortex, cerebellum and hippocampus were examined. The levels of active and oxidized forms of ThDP (enzymatically measured) in the blood and brain, ROS and SH-groups in the brain were also analyzed. RESULTS TD increased the expression of THTR1 and protein level in all studied regions. In contrast, expression of TPK1 was depressed. TD-induced OS led to the accumulation of ThDP oxidized inactive form (ThDPox) in the blood and brain. In vitro reduction of ThDPox by dithiothreitol regenerates active ThDP suggesting that ThDPox is in disulfide form. A single high-dose thiamine administration to TD animals had no effect on THTR1 expression, partly raised TPK1 mRNA and protein levels, but is unable to normalize TPK1 enzyme activity. Brain and blood ThDP levels were increased in these conditions, but ThDPox was not decreased. GENERAL SIGNIFICANCE It is likely, that the accumulation of ThDPox in tissue could be seen as a potential marker of neurocellular dysfunction and thiamine metabolic state.
Collapse
|
2
|
Bolaños-Burgos IC, Bernal-Correa AM, Mahecha GAB, Ribeiro ÂM, Kushmerick C. Thiamine Deficiency Increases Intrinsic Excitability of Mouse Cerebellar Purkinje Cells. THE CEREBELLUM 2020; 20:186-202. [PMID: 33098550 DOI: 10.1007/s12311-020-01202-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/08/2020] [Indexed: 10/23/2022]
Abstract
Thiamine deficiency is associated with cerebellar dysfunction; however, the consequences of thiamine deficiency on the electrophysiological properties of cerebellar Purkinje cells are poorly understood. Here, we evaluated these parameters in brain slices containing cerebellar vermis. Adult mice were maintained for 12-13 days on a thiamine-free diet coupled with daily injections of pyrithiamine, an inhibitor of thiamine phosphorylation. Morphological analysis revealed a 20% reduction in Purkinje cell and nuclear volume in thiamine-deficient animals compared to feeding-matched controls, with no reduction in cell count. Under whole-cell current clamp, thiamine-deficient Purkinje cells required significantly less current injection to fire an action potential. This reduction in rheobase was not due to a change in voltage threshold. Rather, thiamine-deficient neurons presented significantly higher input resistance specifically in the voltage range just below threshold, which increases their sensitivity to current at these critical membrane potentials. In addition, thiamine deficiency caused a significant decrease in the amplitude of the action potential afterhyperpolarization, broadened the action potential, and decreased the current threshold for depolarization block. When thiamine-deficient animals were allowed to recover for 1 week on a normal diet, rheobase, threshold, action potential half-width, and depolarization block threshold were no longer different from controls. We conclude that thiamine deficiency causes significant but reversible changes to the electrophysiology properties of Purkinje cells prior to pathological morphological alterations or cell loss. Thus, the data obtained in the present study indicate that increased excitability of Purkinje cells may represent a leading indicator of cerebellar dysfunction caused by lack of thiamine.
Collapse
Affiliation(s)
| | - Ana María Bernal-Correa
- Graduate Program in Physiology and Pharmacology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | - Ângela Maria Ribeiro
- Graduate Program in Neuroscience, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.,Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Christopher Kushmerick
- Graduate Program in Neuroscience, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. .,Graduate Program in Physiology and Pharmacology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. .,Department of Physiology and Biophysics, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
| |
Collapse
|
3
|
Wang C, Zhang S, Zou Y, Ma H, Jiang D, Sheng L, Sang S, Jin L, Guan Y, Gui Y, Xu Z, Zhong C. A novel PET tracer 18F-deoxy-thiamine: synthesis, metabolic kinetics, and evaluation on cerebral thiamine metabolism status. EJNMMI Res 2020; 10:126. [PMID: 33079296 PMCID: PMC7575681 DOI: 10.1186/s13550-020-00710-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 09/24/2020] [Indexed: 11/27/2022] Open
Abstract
Background Some neuropsychological diseases are associated with abnormal thiamine metabolism, including Korsakoff–Wernicke syndrome and Alzheimer’s disease. However, in vivo detection of the status of brain thiamine metabolism is still unavailable and needs to be developed. Methods A novel PET tracer of 18F-deoxy-thiamine was synthesized using an automated module via a two-step route. The main quality control parameters, such as specific activity and radiochemical purity, were evaluated by high-performance liquid chromatography (HPLC). Radiochemical concentration was determined by radioactivity calibrator. Metabolic kinetics and the level of 18F-deoxy-thiamine in brains of mice and marmosets were studied by micro-positron emission tomography/computed tomography (PET/CT). In vivo stability, renal excretion rate, and biodistribution of 18F-deoxy-thiamine in the mice were assayed using HPLC and γ-counter, respectively. Also, the correlation between the retention of cerebral 18F-deoxy-thiamine in 60 min after injection as represented by the area under the curve (AUC) and blood thiamine levels was investigated. Results The 18F-deoxy-thiamine was stable both in vitro and in vivo. The uptake and clearance of 18F-deoxy-thiamine were quick in the mice. It reached the max standard uptake value (SUVmax) of 4.61 ± 0.53 in the liver within 1 min, 18.67 ± 7.04 in the kidney within half a minute. The SUV dropped to 0.72 ± 0.05 and 0.77 ± 0.35 after 60 min of injection in the liver and kidney, respectively. After injection, kidney, liver, and pancreas exhibited high accumulation level of 18F-deoxy-thiamine, while brain, muscle, fat, and gonad showed low accumulation concentration, consistent with previous reports on thiamine distribution in mice. Within 90 min after injection, the level of 18F-deoxy-thiamine in the brain of C57BL/6 mice with thiamine deficiency (TD) was 1.9 times higher than that in control mice, and was 3.1 times higher in ICR mice with TD than that in control mice. The AUC of the tracer in the brain of marmosets within 60 min was 29.33 ± 5.15 and negatively correlated with blood thiamine diphosphate levels (r = − 0.985, p = 0.015). Conclusion The 18F-deoxy-thiamine meets the requirements for ideal PET tracer for in vivo detecting the status of cerebral thiamine metabolism.
Collapse
Affiliation(s)
- Changpeng Wang
- Department of Neurology, Zhongshan Hospital, State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, 200032, China
| | - Siwei Zhang
- Jiangsu Huayi Technology Co., Ltd., Jiangsu, 215519, China
| | - Yuefei Zou
- Jiangsu Huayi Technology Co., Ltd., Jiangsu, 215519, China
| | - Hongzhao Ma
- Jiangsu Huayi Technology Co., Ltd., Jiangsu, 215519, China
| | - Donglang Jiang
- PET Center, Huashan Hospital, Fudan University, Shanghai, 200235, China
| | - Lei Sheng
- Department of Clinical Pharmacology, Zhongshan Hospital, Fudan University, Shanghai, 200032, China
| | - Shaoming Sang
- Department of Neurology, Zhongshan Hospital, State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, 200032, China
| | - Lirong Jin
- Department of Neurology, Zhongshan Hospital, State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, 200032, China
| | - Yihui Guan
- PET Center, Huashan Hospital, Fudan University, Shanghai, 200235, China
| | - Yuan Gui
- Jiangsu Huayi Technology Co., Ltd., Jiangsu, 215519, China
| | - Zhihong Xu
- Jiangsu Huayi Technology Co., Ltd., Jiangsu, 215519, China
| | - Chunjiu Zhong
- Department of Neurology, Zhongshan Hospital, State Key Laboratory of Medical Neurobiology and Institute of Brain Science, Fudan University, Shanghai, 200032, China.
| |
Collapse
|
4
|
Isen DR, Kline LB. Neuro-ophthalmic Manifestations of Wernicke Encephalopathy. Eye Brain 2020; 12:49-60. [PMID: 32636690 PMCID: PMC7335288 DOI: 10.2147/eb.s234078] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 06/09/2020] [Indexed: 12/18/2022] Open
Abstract
Wernicke encephalopathy (WE) is a life-threatening but reversible syndrome resulting from acute thiamine deficiency that is frequently overlooked and underdiagnosed. It is classically characterized by a triad of ocular dysfunction, ataxia, and altered mental status. However, less than 1/3 patients have the complete triad, so it is crucial to have a high index of suspicion. Awareness of the early signs of WE is essential to prevent clinical progression, as patients with the full triad already have a profoundly thiamine-deficient state. This review highlights the neuro-ophthalmic manifestations of WE to guide the clinician in identifying the condition. In addition, we provide an update regarding the clinical characteristics, pathophysiology, neuroimaging and laboratory findings, treatment options, and prognosis of WE.
Collapse
Affiliation(s)
- Danielle R Isen
- Department of Neurology, University of South Alabama School of Medicine, Mobile, AL, USA
| | - Lanning B Kline
- Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, AL, USA
| |
Collapse
|
5
|
Development of thiamine and pyridoxine loaded ferulic acid-grafted chitosan microspheres for dietary supplementation. Journal of Food Science and Technology 2015; 53:551-560. [PMID: 26787974 DOI: 10.1007/s13197-015-2044-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 09/12/2015] [Accepted: 09/16/2015] [Indexed: 10/23/2022]
Abstract
Therapeutic potential of water soluble vitamins has been known for long and in recent times they are being widely supplemented in processed food. Phenolic acid-grafted chitosan derivatives can serve as excellent biofunctional encapsulating materials for these vitamins. As a proof of concept, thiamine and pyridoxine loaded ferulic acid-grafted chitosan microspheres were developed. Ferulic acid was successfully grafted on chitosan by a free radical mediated reaction and the structure was confirmed by FTIR and NMR analysis. When compared to FTIR spectra of chitosan, intensity of amide I (at around 1644 cm(-1)) and amide II (at around 1549 cm(-1)) bands in spectra of ferulic acid-grafted chitosan were found increased, indicating formation of new amide linkage. Strong signals at δ = 6.3-7.9 ppm corresponding to methine protons of ferulic acid were observed in NMR spectra of ferulic acid-grafted chitosan, suggesting the successful grafting of ferulic acid onto chitosan. Grafting ratio of the derivative was 263 mg ferulic acid equivalent/g polymer. Positively charged particles (zeta potential 31 mv) of mean diameter 4.5 and 4.8 μ, corresponding to number distribution and area distribution respectively were observed. Compact microspheres with smooth surfaces and no apparent cracks or pores were observed under scanning electron microscope. Efficient microencapsulation was further proved by X-ray diffraction patterns and thermal analysis. Preliminary anti-inflammatory activity of the vitamin-loaded microspheres was demonstrated.
Collapse
|