Theanine, Antistress Amino Acid in Tea Leaves, Causes Hippocampal Metabolic Changes and Antidepressant Effects in Stress-Loaded Mice
Abstract
:1. Introduction
2. Results
2.1. Effects of Theanine Ingestion on Brain Metabolites in Senescence-Accelerated Mouse Prone 10 (SAMP10) and ddY Mice Stressed by Confrontational Housing
2.2. Effect of Theanine Ingestion on Depression-Like Behavior
2.3. Effect of Theanine Ingestion on the Levels of Indoleamine/Tryptophan-2,3-dioxygenase, Arginase and Histidine Decarboxylase
3. Discussion
4. Materials and Methods
4.1. Animals and Theanine Preparation
4.2. Housing Conditions for Stress Experiments
4.3. Measurement of Metabolites by Ultrahigh Liquid Chromatography-Tandem Mass Spectrometry (UHPLC-MS/MS)
4.4. Principal Component Analysis
4.5. Tail-Suspension Test
4.6. Quantitative Real-Time Reverse Transcription PCR (qRT-PCR)
4.7. Statistical Analyses
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
Abbreviations
Arg | Arginine |
CMP | Cytidine monophosphate |
GABA | γ-Aminobutyric acid |
GMP | Guanosine monophosphate |
HDC | Histidine decarboxylase |
IDO | Indoleamine-2,3-dioxygenase |
Kyn | Kynurenine |
Lcn2 | Lipocalin 2 |
NO | Nitric oxide |
Npas4 | Neuronal PAS domain protein 4 |
Orn | Ornithine |
PC | Principal component |
PCA | Principal component analysis |
Put | Putrescine |
SAMP10 | Senescence-accelerated mice prone 10 |
Trp | Tryptophan |
TDO | Tryptophan-2,3-dioxygenase |
UHPLC-MS/MS | Ultra-high performance liquid chromatography-tandem mass spectrometry |
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Mouse | Condition | Treatment | PC1 | PC2 | PC3 | PC4 |
---|---|---|---|---|---|---|
SAMP10 | Group | Control | –0.07338 | 0.03785 | –0.00872 | –0.00107 |
–0.03254 | –0.00421 | –0.02051 | –0.00247 | |||
–0.07107 | 0.03476 | –0.00459 | –0.00835 | |||
–0.03904 | –0.00196 | –0.00954 | –0.01278 | |||
Theanine | –0.07666 | 0.02389 | 0.00652 | 0.01317 | ||
–0.06840 | 0.02850 | –0.00088 | 0.00442 | |||
–0.07974 | 0.02936 | 0.01287 | 0.00789 | |||
Confrontation | Control | –0.04038 | 0.00882 | 0.01114 | –0.02924 | |
–0.04848 | –0.01130 | 0.00611 | –0.01154 | |||
–0.06143 | 0.00294 | 0.01720 | 0.00465 | |||
–0.00513 | –0.06122 | 0.00394 | 0.00318 | |||
Theanine | 0.00952 | –0.10804 | –0.01076 | 0.00681 | ||
–0.00350 | –0.05210 | 0.01452 | 0.02649 | |||
0.01278 | –0.11432 | –0.00996 | –0.01817 | |||
–0.02355 | –0.03912 | 0.00415 | –0.00177 | |||
ddY | Group | Control | 0.01670 | 0.00225 | –0.01376 | –0.02015 |
0.01147 | 0.00520 | –0.01819 | –0.00116 | |||
0.02528 | 0.00516 | –0.01773 | 0.01430 | |||
Theanine | –0.00682 | 0.00349 | 0.00519 | 0.01326 | ||
–0.04108 | –0.01144 | –0.00352 | 0.02319 | |||
0.02797 | 0.00704 | 0.00463 | 0.00567 | |||
0.17347 | 0.04502 | 0.02486 | 0.01496 | |||
Confrontation | Control | 0.09426 | 0.02753 | –0.00925 | 0.01045 | |
0.04019 | 0.00548 | –0.02618 | –0.01805 | |||
0.09584 | 0.02586 | 0.01472 | 0.00620 | |||
–0.01268 | –0.03017 | –0.02188 | 0.02948 | |||
Theanine | 0.07307 | 0.01096 | 0.02558 | –0.03502 | ||
0.06694 | 0.01848 | 0.00251 | 0.00074 | |||
0.04413 | 0.00230 | –0.02052 | –0.02141 | |||
0.14107 | 0.03713 | 0.02662 | 0.01047 |
Metaborites | PC1 | PC2 |
---|---|---|
Kynurenine | −0.12390 | 0.02227 |
Histamine | −0.06985 | 0.00491 |
5-Methoxytryptamine | −0.03622 | −0.08937 |
2.4-Diaminobutyric.acid | −0.03085 | −0.00003 |
Histidinol | −0.02561 | 0.00316 |
5-Aminovaleric.acid | −0.02370 | −0.00610 |
Cadaverine | −0.02067 | −0.00384 |
Diacetyl spermidine | −0.01859 | 0.00364 |
3-Methoxyanthranilate | −0.01750 | −0.00783 |
Leucine | −0.00513 | 0.00335 |
Methionine | −0.00364 | 0.00280 |
Proline | −0.00277 | 0.00327 |
Creatinine | −0.00269 | −0.00184 |
2-Aminoadipate | −0.00263 | −0.00433 |
Aspartic acid | −0.00229 | −0.00076 |
Arginine | −0.00213 | 0.00345 |
Cystine | −0.00201 | 0.00122 |
2-Aminobutyric.acid | −0.00160 | 0.00033 |
Valine | −0.00124 | 0.00227 |
Phenylalanine | −0.00119 | 0.00302 |
Alanine | −0.00084 | 0.00084 |
β-Alanine | −0.00064 | 0.00208 |
NG-monomethyl-arginine | −0.00028 | −0.00849 |
Isoleucine | −0.00019 | 0.00310 |
Glutamine | −0.00008 | −0.00027 |
Histidine | 0.00037 | 0.00187 |
Hypoxanthine | 0.00103 | 0.00440 |
Glutamic acid | 0.00132 | −0.00123 |
Spermidine | 0.00143 | −0.00015 |
Glutathione reduced | 0.00146 | −0.00238 |
Serine | 0.00162 | −0.00050 |
CMP | 0.00262 | 0.00253 |
Adenine | 0.00368 | −0.01675 |
Adenosine | 0.00482 | −0.00904 |
Ornithine | 0.00487 | −0.00004 |
Putrescine | 0.00668 | −0.01895 |
Carnosine | 0.00901 | 0.00522 |
GMP | 0.01038 | −0.00718 |
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Unno, K.; Muguruma, Y.; Inoue, K.; Konishi, T.; Taguchi, K.; Hasegawa-Ishii, S.; Shimada, A.; Nakamura, Y. Theanine, Antistress Amino Acid in Tea Leaves, Causes Hippocampal Metabolic Changes and Antidepressant Effects in Stress-Loaded Mice. Int. J. Mol. Sci. 2021, 22, 193. https://doi.org/10.3390/ijms22010193
Unno K, Muguruma Y, Inoue K, Konishi T, Taguchi K, Hasegawa-Ishii S, Shimada A, Nakamura Y. Theanine, Antistress Amino Acid in Tea Leaves, Causes Hippocampal Metabolic Changes and Antidepressant Effects in Stress-Loaded Mice. International Journal of Molecular Sciences. 2021; 22(1):193. https://doi.org/10.3390/ijms22010193
Chicago/Turabian StyleUnno, Keiko, Yoshio Muguruma, Koichi Inoue, Tomokazu Konishi, Kyoko Taguchi, Sanae Hasegawa-Ishii, Atsuyoshi Shimada, and Yoriyuki Nakamura. 2021. "Theanine, Antistress Amino Acid in Tea Leaves, Causes Hippocampal Metabolic Changes and Antidepressant Effects in Stress-Loaded Mice" International Journal of Molecular Sciences 22, no. 1: 193. https://doi.org/10.3390/ijms22010193