theanine, memory

Adaptogens are a group of substances capable to increase the nonspecific resistance of the organism to a wide range of harmful effects and stress. However, only limited data exist on their use in the composition of foods for special dietary uses. The aim of the study was to evaluate the effect of a diet that included vegetable-fat spread enriched with 5-hydroxytryptophan, L-theanine and γ-aminobutyric acid on memory, general well-being and emotional status of healthy volunteers. Material and methods ...

In 2021, the Global Brain Health Supplement Industry Market size was valued at US$7.6 billion. It is predicted to increase to US$15.59 billion by 2030. Memory and its enhancement are a segment of the market that comprised the highest global revenue share in 2021. In the USA alone, dietary supplement sales reached US$18 billion in 2018. The US Food and Drug Administration (FDA) does not have the authority to approve dietary supplements' safety, effectiveness, or labeling before products go on the market...

BACKGROUND: Stress and everyday problems may impact memory and cognition. Therefore, many people use cognitive enhancers (CEs), sold for prescription, as over-the-counter drugs, or dietary supplements, believing they may help with everyday functioning. Our study was designed to answer whether taking CEs is common among Medical University students and to identify which substances are mainly used. METHODS AND RESULTS: An anonymous online questionnaire was answered by 479 students of Medical (88%) and Dentistry (12%) Faculties in Poland...

Blood brain barrier (BBB) impairment was related to the development of Alzheimer's disease (AD), which was dependent not only on tight junction but also on transcytosis of brain endothelial cells (BECs) in BBB. Aging induced the decrease of ligand-specific receptor-mediated transcytosis (RMT) and the increase of non-specific caveolar transcytosis in BECs, which led to the entry into parenchyma of neurotoxic proteins and the smaller therapeutic index in central nervous system drug delivery, further provoke neurodegenerative disease...

The complex pathogenesis of Alzheimer's disease (AD) leads to a limited therapeutic effect; therefore, the combination of multiple bioactive ingredients may be more effective in improving AD due to synergistic effects. Based on the perspective of the sea-land combination, the effects of sea-derived Antarctic krill oil (AKO) combined with land-derived nobiletin (Nob) and L-theanine (The) on memory loss and cognitive deficiency were studied in senescence-accelerated prone 8 mice (SAMP8). The results demonstrated that AKO combined with The significantly increased the number of platform crossings in the Morris water maze test by 1...

Although the benefits of the consumption of green tea and its components, including catechins and theanine, regarding aging, memory impairment and age-related cognitive decline have been investigated in senescence-accelerated prone mice (SAMP8), studies that simultaneously measured the kinds of proteins that vary in their expression due to the administration of green tea and its extracts were not found. In this study, the effect of dietary and decaffeinated matcha on protein expression in the hippocampus of SAMP 8 was examined comprehensively, mainly using proteomics...

Attention-deficit hyperactivity disorder (ADHD) affects multiple cognitive domains, including impaired attention, hyperactivity, and increased impulsivity. According to the CDC, 9.4% of children between 2 and 17 years old have been diagnosed with ADHD. Neurotransmitters such as noradrenaline and dopamine have been suggested as crucial players in the pathophysiology of ADHD and are often targets of modern medication. Adenosine receptors types A1 and A2a in the brain are inhibited by caffeine: a stimulant known to augment attention by increasing cholinergic and dopaminergic transmission...

l-theanine ( γ -glutamylethylamide), an amino acid in green tea, has been shown to affect brain functions by relieving stress disorders, improving mood, and maintaining normal sleep. However, the cognitive functions for which theanine is effective are unclear. This study aimed to clarify which cognitive functions are positively affected by intake of l-theanine. A double-blind, randomized, placebo-controlled study was conducted. The subjects were Japanese men and women aged 50-69 years. Mini Mental State Examination-Japanese version score was 24 or higher...

Tea is a beverage commonly consumed worldwide. Matcha is a type of green tea produced by drying and grinding tea leaves (Camellia sinensis L.) into a fine powder. Matcha contains catechin, theanine, and caffeine, which affect cognitive function. Epidemiological studies conducted in Japan have shown that green tea consumption improves cognitive impairment. Previously, we found that daily matcha intake improves attention and executive function in middle-aged and older people. However, its effect on cognitive function in younger adults remains unclear...

Theanine (thea) is one of the most important plant-derived characteristic secondary metabolites and a major healthcare product because of its beneficial biological activities, such as being an antianxiety agent, promoting memory, and lowering blood pressure. Thea mostly accumulates in Camellia plants and is especially rich in Camellia sinensis (tea plant). Although some functional genes (e.g., TS , GOGAT , and GS ) attributed to thea accumulation have been separately well explored in tea plants, the evolution of a regulatory module (highly interacting gene group) related to thea metabolism remains to be elaborated...

Green tea (Camellia sinensis) is a popular herbal plant with abundant health benefits, and thus, it has been used as a potent antioxidant for a long time. Based on the available literature, the diversity and the availability of multifunctional compounds in green tea offer its noteworthy potential against many diseases such as liver and heart diseases, inflammatory conditions and different metabolic syndromes. Owing to its bioactive constituents including caffeine, amino acids, l-theanine, polyphenols/flavonoids and carbohydrates among other potent molecules, green tea has many pharmacological and physiological effects...

Objectives: The present study is designed to investigate the effectiveness of L-theanine (Suntheanine®) among patients with major depression disorder (MDD). Methods: Twenty patients were recruited with moderate MDD (4 males; mean age: 41.0 ± 14.1 years, and 16 females; 42.9 ± 12.0 years) for this open-label clinical study. Participants were supplemented with L-theanine (250 mg/day) along with their current medication for 8 consecutive weeks. The cognitive functions and related symptoms were evaluated at baseline, 4 weeks, and 8 weeks after L-theanine supplementation using advanced version (21-items) of the Hamilton Depression Rating Scale (HAMD-21), Pittsburgh Sleep Quality Index (PSQI), State-Trait Anxiety Inventory (STAI), Brief Assessment of Cognition in Schizophrenia (BACS), including the Stroop test...

Theanine is an analog of glutamate and the major aminoacid in green tea. It has received growing attention in recent years because of its beneficial effects on the central nervous system. Theanine was shown to increase levels of brain-derived neurotrophic factor and to stimulate neurogenesis. Anti-stress and calming effects of theanine are the most apparent and well-studied. A number of studies showed neuroprotective effects of theanine after an ischemic cerebral injury or the exposure to toxic chemicals. It also improved cognitive function including attention, memory and learning...

Theanine (γ-glutamylethylamide), an amino acid in tea, is a putative neuroprotective and antioxidant compound capable of improving lifespan and cognitive function. Because we previously reported cognitive dysfunction in klotho mutant mice via down-regulation of janus kinase 2 (JAK2) and signal transducer and activator of transcription3 (STAT3), M1 muscarinic cholinergic receptor (M1 mAChR), and ERK signaling, we, therefore, investigated whether self-administration of theanine affects memory dysfunction in response to klotho gene depletion in mice, and whether theanine modulates the JAK2/STAT3, M1 mAChR, and ERK signaling network...

Luteolin and l-theanine have anti-inflammatory, antioxidant, and possible antidiabetic activities, and they may synergistically protect against dementia. Here, we hypothesized that a combination of luteolin and l-theanine would synergistically act to improve memory function and glucose disturbances in rats infused with amyloid-β, and the mechanisms underlying these actions were investigated. Rats that received an amyloid-β(25-35) infusion into the CA1 region of the hippocampus were fed dextrin (AD-CON), 0...

Synaptic refinement improves synaptic efficiency, which provides a possibility to improve memory in Alzheimer's disease (AD). In the current study, we aimed to investigate the role of L-theanine, a natural constituent in green tea, in hippocampal synaptic transmission and to assess its potential to improve memory in transgenic AD mice. Initially, we found that L-theanine bath application facilitated hippocampal synaptic transmission and reduced paired-pulse facilitation (PPF). These effects were blocked by antagonists of N-methyl-D-aspartic acid receptors and the dopamine D1/5 receptor, and a selective protein kinase A (PKA) inhibitor...

OBJECTIVES: Few previous studies have assessed the effects of concomitant administration of multiple potentially psychoactive nutrients. METHODS: 95 healthy adult participants consumed either a nutrient enriched breakfast bar (containing α-Linolenic acid, l-tyrosine, l-theanine, vitamins, minerals and 21.5 mg of caffeine) or an isocaloric, macronutrient matched control bar for 56 days. Cognitive function and mood were assessed pre-dose and at 40- and 160-min post-dose on the 1st and 56th day of the intervention period...

BACKGROUND: The prevalence of senile dementia is increasing worldwide, especially in the developed countries. Nevertheless, drug therapy isn't often enough to treat this condition. Researchers are evaluating the possible impact of a preventive approach, based on an improvement of lifestyle and the intake of micronutrients. Moreover, there is an increasing interest for combined nutraceuticals that can act as memory and learning enhancers, with a significant and beneficial potential on the cognitive disorders...

BACKGROUND: Green tea (Camellia sinensis) is a beverage consumed for thousands of years. Numerous claims about the benefits of its consumption were stated and investigated. As green tea is experiencing a surge in popularity in Western culture and as millions of people all over the world drink it every day, it is relevant to understand its effects on the human brain. PURPOSE: To assess the current state of knowledge in the literature regarding the effects of green tea or green tea extracts, l-theanine and epigallocatechin gallate both components of green tea-on general neuropsychology, on the sub-category cognition and on brain functions in humans...

BACKGROUND: Green tea is traditionally known to induce mental clarity, cognitive function, physical activation and relaxation. Recently, a special green tea, matcha tea, is rapidly gaining popularity throughout the world and is frequently referred to as a mood- and brain food. Matcha tea consumption leads to much higher intake of green tea phytochemicals compared to regular green tea. Previous research on tea constituents caffeine, L-theanine, and epigallocatechin gallate (EGCG) repeatedly demonstrated benefits on mood and cognitive performance...