L-Theanin beyin kesitlerinde epileptiform aktiviteyi azaltır

Yıl 2022, Cilt: 8 Sayı: 2, 121 - 127, 01.05.2022

Harun Başoğlu Hilal Öztürk Hatice Keser , Selcen Aydin-abidin İsmail Abidin

https://doi.org/10.53394/akd.1057342

Cited By: 2

Öz

L-Theanin Beyin Kesitlerinde Epileptiform Aktiviteyi Azaltır
ÖZ
Amaç: L-theanine, kan beyin bariyerini geçebilen çay bitkisinin ana amino asitlerinden biridir. Merkezi sinir sisteminde, L-theanine'in bir dizi nörotransmiter sistemi üzerinde belirli etkileri vardır. Bu çalışmada, L-theanine'nin akut uygulamasının beyin kesitlerinde herhangi bir nöbet benzeri veya inhibe edici aktiviteye yol açıp açmayacağını test ettik.
Gereç ve Yöntemler: L-theanine'in epileptiform aktivite üzerindeki etkileri iki farklı beyin bölgesinde araştırıldı. Yatay hipokampal-entorinal korteks dilimleri, 32-36 günlük C57BL/6 farelerinden elde edildi. Hücre dışı alan potansiyelleri medial entorinal korteks (EC) ve hipokampusun CA3 bölgesinden kaydedildi. Epileptiform aktivite, beyin dilimlerine 4 Aminopiridin (4AP, 100 µM) uygulanarak indüklendi ve 50 µM L-theanine uygulandı. Kayıtlardan iktal benzeri olayların süresi ve sıklığı ile interiktal benzeri aktivitelerin frekansı ve genliği hesaplandı.
Bulgular: L-theanine tek başına herhangi bir senkronize aktivite başlatmadı. 4AP ile indüklenen epileptiform aktivite sonrası L-theanine'in banyo uygulaması iktal deşarjların süresini ve sıklığını önemli ölçüde değiştirmese de, L-theanine interiktal deşarjları azalttı. EC'de interiktal deşarjların sıklıkları anlamlı ölçüde azaldı. CA3'te, interiktal aktivitelerin amplitüdleri anlamlı ölçüde azaldı.
Sonuç: Bulgularımız, L-theanine'in herhangi bir nöbet benzeri olay uyarmadığını, bunun yerine devam eden epileptiform aktivite üzerinde baskılayıcı bir etkiye sahip olduğunu göstermektedir.
Anahtar Sözcükler: Theanine, 4 Aminopiridin, Beyin Kesiti, Epileptiform aktivite, CA3, Entorinal Korteks

Anahtar Kelimeler

Theanine, 4 Aminopiridin, Beyin Kesiti, Epileptiform aktivite, CA3, Entorinal Korteks

L-Theanine Reduces Epileptiform Activity In Brain Slices

Öz

L-Theanine Reduces Epileptiform Activity In Brain Slices
ABSTRACT
Objective: L-theanine is one of the main amino acid of tea plant which can cross the blood brain barrier. In the central nervous system, L-theanine has certain effects on a number of neurotransmitter systems. In this study we tested whether acute application of L-theanine could induce any seizure like or inhibitory activity in the brain slice.
Materials and Methods: Effects of L-theanine on epileptiform activity were investigated in two different brain regions. Horizontal hippocampal-entorhinal cortex slices were obtained from 30-35 days old C57BL/6 mice. Extracellular field potentials were recorded from medial entorhinal cortex (EC) and CA3 region of hippocampus. Epileptiform activity was induced by application of 4 Aminopyridine (4AP, 100 µM) in the brain slices and 50 µM L-theanine was applied. From the recordings, the duration and frequencies of ictal like events as well as frequency and amplitude of inter-ictal like activities were calculated.
Results: L-theanine alone did not initiate any synchronized activity. Although, bath application of L-theanine after 4AP induces epileptiform acitivities, did not significantly alter the duration and frequency of ictal discharges, L-theanine attenuated the interictal discharges. In EC the frequencies of interictal discharges were significantly decreased. In CA3, the amplitudes of interictal activities were significantly reduced.
Conclusion: The present findings suggest that L-theanine do not induce any seizure like event but rather had a suppressive effect on ongoing epileptiform activity.
Key Words: Theanine, 4 Aminopyridine, Brain Slice, Epileptiform activity, CA3, Entorhinal cortex

Anahtar Kelimeler

Theanine, 4 Aminopyridine, Brain Slice, Epileptiform activity, CA3, Entorhinal cortex

Kaynakça

• 1. Türközü D, Şanlier N. L-theanine, unique amino acid of tea, and its metabolism, health effects, and safety. Critical reviews in food science and nutrition. 2017;57(8):1681-7.
• 2. Yokogoshi H, Kobayashi M, Mochizuki M, Terashima T. Effect of theanine, r-glutamylethylamide, on brain monoamines and striatal dopamine release in conscious rats. Neurochemical research. 1998;23(5):667-73.
• 3. Kimura K, Ozeki M, Juneja LR, Ohira H. L-Theanine reduces psychological and physiological stress responses. Biological psychology. 2007;74(1):39-45.
• 4. Takeshima M, Miyazaki I, Murakami S, Kita T, Asanuma M. l-Theanine protects against excess dopamine-induced neurotoxicity in the presence of astrocytes. Journal of clinical biochemistry and nutrition. 2016;59(2):93-9.
• 5. Kim TI, Lee YK, Park SG, Choi IS, Ban JO, Park HK, Nam SY, Yun YW, Han SB, Oh KW, Hong JT. l-Theanine, an amino acid in green tea, attenuates beta-amyloid-induced cognitive dysfunction and neurotoxicity: reduction in oxidative damage and inactivation of ERK/p38 kinase and NF-kappaB pathways. Free radical biology & medicine. 2009;47(11):1601-10.
• 6. Albrecht J, Sidoryk-Węgrzynowicz M, Zielińska M, Aschner M. Roles of glutamine in neurotransmission. Neuron glia biology. 2010;6(4):263-76.
• 7. Yoneda Y. An L-Glutamine Transporter Isoform for Neurogenesis Facilitated by L-Theanine. Neurochemical research. 2017;42(10):2686-97.
• 8. Yoneda Y, Kuramoto N, Kawada K. The role of glutamine in neurogenesis promoted by the green tea amino acid theanine in neural progenitor cells for brain health. Neurochemistry international. 2019;129:104505.
• 9. Zhao J, Zhao X, Tian J, Xue R, Luo B, Lv J, Gao J, Wang M.Theanine attenuates hippocampus damage of rat cerebral ischemia-reperfusion injury by inhibiting HO-1 expression and activating ERK1/2 pathway. Life sciences. 2020;241:117160.
• 10. Egashira N, Hayakawa K, Osajima M, Mishima K, Iwasaki K, Oishi R, Fujivara M. Involvement of GABA(A) receptors in the neuroprotective effect of theanine on focal cerebral ischemia in mice. Journal of pharmacological sciences. 2007;105(2):211-4.
• 11. Yamada T, Terashima T, Kawano S, Furuno R, Okubo T, Juneja LR, Yokogoshi H. Theanine, gamma-glutamylethylamide, a unique amino acid in tea leaves, modulates neurotransmitter concentrations in the brain striatum interstitium in conscious rats. Amino acids. 2009;36(1):21-7.
• 12. Uhlhaas PJ, Singer W. Neural synchrony in brain disorders: relevance for cognitive dysfunctions and pathophysiology. Neuron. 2006;52(1):155-68.
• 13. Scharfman HE. The neurobiology of epilepsy. Current neurology and neuroscience reports. 2007;7(4):348-54.
• 14. Gomes A, Das M, Vedasiromoni JR, Ganguly DK. Proconvulsive effect of tea (Camellia sinensis) in mice. Phytotherapy research : PTR. 1999;13(5):376-9.
• 15. Schallier A, Vermoesen K, Loyens E, Van Liefferinge J, Michotte Y, Smolders I, et al. L-Theanine intake increases threshold for limbic seizures but decreases threshold for generalized seizures. Nutritional neuroscience. 2013;16(2):78-82.
• 16. Abidin İ, Aydin-Abidin S, Mittmann T. Neuronal excitability and spontaneous synaptic transmission in the entorhinal cortex of BDNF heterozygous mice. Neuroscience letters. 2019;690:69-75.
• 17. Aydin-Abidin S, Abidin İ. 7,8-Dihydroxyflavone potentiates ongoing epileptiform activity in mice brain slices. Neuroscience letters. 2019;703:25-31.
• 18. Zhu G, Yang S, Xie Z, Wan X. Synaptic modification by L-theanine, a natural constituent in green tea, rescues the impairment of hippocampal long-term potentiation and memory in AD mice. Neuropharmacology. 2018;138:331-40.
• 19. D'Arcangelo G, Panuccio G, Tancredi V, Avoli M. Repetitive low-frequency stimulation reduces epileptiform synchronization in limbic neuronal networks. Neurobiology of disease. 2005;19(1-2):119-28.
• 20. Myers TL, Gonzalez OC, Stein JB, Bazhenov M. Characterizing Concentration-Dependent Neural Dynamics of 4-Aminopyridine-Induced Epileptiform Activity. Epilepsy journal. 2018;4(2).
• 21. Panuccio G, Sanchez G, Lévesque M, Salami P, de Curtis M, Avoli M. On the ictogenic properties of the piriform cortex in vitro. Epilepsia. 2012;53(3):459-68.
• 22. Uva L, Breschi GL, Gnatkovsky V, Taverna S, de Curtis M. Synchronous inhibitory potentials precede seizure-like events in acute models of focal limbic seizures. The Journal of neuroscience : the official journal of the Society for Neuroscience. 2015;35(7):3048-55.
• 23. Kakuda T, Nozawa A, Sugimoto A, Niino H. Inhibition by theanine of binding of [3H]AMPA, [3H]kainate, and [3H]MDL 105,519 to glutamate receptors. Bioscience, biotechnology, and biochemistry. 2002;66(12):2683-6.
• 24. Avoli M, Biagini G, de Curtis M. Do interictal spikes sustain seizures and epileptogenesis? Epilepsy currents. 2006;6(6):203-7.
• 25. Yu XC, Wu BL, Gao JC, Yang W. Theanine enhanced both the toxicity of strychnine and anticonvulsion of pentobarbital sodium. Drug and chemical toxicology. 2016;39(2):217-23.
• 26. Kimura R, Murata T. Influence of alkylamides of glutamic acid and related compounds on the central nervous system. I. Central depressant effect of theanine. Chemical & pharmaceutical bulletin. 1971;19(6):1257-61.
• 27. Sebih F, Rousset M, Bellahouel S, Rolland M, de Jesus Ferreira MC, Guiramand J, et al. Characterization of l-Theanine Excitatory Actions on Hippocampal Neurons: Toward the Generation of Novel N-Methyl-d-aspartate Receptor Modulators Based on Its Backbone. 2017;8(8):1724-34.