Natural remedies for Alzheimer's disease: A systematic review of randomized controlled trials.

Alzheimer's disease (AD) is the common type of dementia and is currently incurable. Existing FDA-approved AD drugs may not be effective for everyone, they cannot cure the disease nor stop its progression and their effects diminish over time. Therefore, the present review aimed to explore the role of natural alternatives in the treatment of AD. A systematic search was conducted using Ovid MEDLINE, CINAHL, Cochrane and PubMed databases and reference lists up to November 30, 2021. Only randomized control trials were included and appraised using the National Institute of Health framework. Data analysis showed that herbs like Gingko Biloba, Melissa Officinalis, Salvia officinalis, Ginseng and saffron alone or in combination with curcumin, low-fat diet, NuAD-Trail, and soy lecithin showed significant positive effects on AD. Moreover, combination of natural and pharmaceuticals has far better effects than only allopathic treatment. Thus, different herbal remedies in combination with FDA approved drugs are effective and more promising in treatment of AD.

Ameliorative effects of half-dose saffron and chamomile combination on Psycho-endocrinological changes in a diabetic murine model.

INTRODUCTION: Diabetes mellitus is a chronic metabolic disorder with an increasing prevalence worldwide. Reduction in blood insulin level alters brain function by inducing oxidative stress with changes in dopamine and norepinephrine neurotransmission, ultimately leading to neuropsychological symptoms. The efficacy of currently available psychotropic drugs is not satisfactory. Therefore, this study was conducted to explore the beneficial effects of a combination of the natural herbs, saffron and chamomile, in treating diabetes and its resultant neuropsychological effects using a rodent model of diabetes mellitus. METHOD: The rats were randomly divided in to eight groups (n = 10), healthy control (HC), diabetic control (DC) and six groups of diabetic rats treated with various concentrations and combinations of saffron and chamomile. Diabetic treatment groups individually received methanolic extract and water decoction of chamomile (30 mg/kg) and saffron (10mg/kg) and their combined half doses (saffron 5mg/kg and chamomile 15mg/kg) for two weeks. Open field test (OFT) and forced swim test (FST) were used to measure the anxiolytic and antidepressant effects of herbs, respectively. Finally, biochemical, and neurochemical estimations were made. RESULTS: The present study suggests the therapeutic effects of herbs especially in co-administrated decoction, against diabetes with improved antioxidant profile and enhanced levels of dopamine and norepinephrine. Anxiolytic and antidepressant effects were evident with improvements in the OFT and FST. Examination of the cortex of the diabetic group revealed cellular damage and tangle formation, which indicates advanced stages of dementia. CONCLUSION: This study shows that the use of a combination of saffron and chamomile improves diabetes control and reduces its related psychiatric effects.

Therapeutic Potential of Curcumin in Reversing the Depression and Associated Pseudodementia via Modulating Stress Hormone, Hippocampal Neurotransmitters, and BDNF Levels in Rats.

Depressive state adversely affects the memory functions, especially in the geriatric population. The initial stage of memory deficits associated with depression is particularly called as pseudodementia. It is the starting point of memory disturbance before dementia. The purpose of this research was to study depression and its consequent pseudodementia. For this purpose 24 male albino Wistar rats were divided into four groups. Depression was induced by 14 days of chronic restraint stress (CRS) daily for 4 h. After developing a depression model, pattern separation test was conducted to monitor pseudodementia in rats. Morris water maze test (MWM) was also performed to observe spatial memory. It was observed that model animals displayed impaired pattern separation and spatial memory. Treatment was started after the development of pseudodementia in rats. Curcumin at a dose of 200 mg/kg was given to model rats for one week along with the stress procedure. Following the treatment with curcumin, rats were again subjected to the aforementioned behavioral tests before decapitation. Corticosterone levels, brain derived neurotrophic factor (BDNF) and neurochemical analysis were conducted. Model rats showed depressogenic behavior and impaired memory performance. In addition to this, high corticosterone levels and decreased hippocampal BDNF, 5-HT, dopamine (DA), and acetylcholine (ACh) levels were also observed in depressed animals. These behavioral biochemical and neurochemical changes were effectively restored following treatment with curcumin. Hence, it is suggested from this study that pseudodementia can be reversed unlike true dementia by controlling the factors such as depression which induce memory impairment.

Spirulina platensis reduces the schizophrenic-like symptoms in rat model by restoring altered APO-E and RTN-4 protein expression in prefrontal cortex.

AIMS: Schizophrenia (SZ) is recognized as a neuropsychiatric disorder in humans with accelerated mortality and profound morbidity followed with impairments in social as well as vocational functioning. Though various antipsychotics are being considered as approved treatment therapy for the psychotic symptoms of SZ but they also exert adverse effects and also lack efficacy in treating full spectrum of the disorder. Spirulina platensis (blue-green algae), a nutritional supplement, constitutes a variety of multi-nutrients and possesses a large number of neuroprotective activities. Therefore, present experimental work was designed to evaluate the neuroprotective effects of spirulina in ameliorating the psychosis-like symptoms in dizocilpine-induced rat model of SZ. MATERIALS AND METHODS: The spirulina was tested as preventive and therapeutic regimen at the dose of 180 mg/kg. After pre- and post-treatment with spirulina, rats were subjected to behavioral assessments followed by biochemical and neurochemical estimations. Biomarkers including APO-E, RTN-4, TNF-α, and IL-6 were also estimated using ELISA. KEY FINDINGS: Present results showed that administration of spirulina not only improved behavioral deficits induced by dizocilpine but it also regulates neurotransmission, oligodendrocyte dysfunction and APO-E over expression. Moreover, it also restores the immune response dysfunction by reducing inflammatory cytokines. SIGNIFICANCE: Thus, from present findings it may be suggested that spirulina aids in ameliorating the psychosis-like symptoms induced by dizocilpine in animal model possibly via regulation of neurotransmission and other biomarkers that are extensively used to uncover the etiopathology of SZ. Hence, blue-green algae can be used as an effective therapy for preventive or therapeutic measures in SZ.

Supplementation of Taurine Insulates Against Oxidative Stress, Confers Neuroprotection and Attenuates Memory Impairment in Noise Stress Exposed Male Wistar Rats.

Noise has always been an important environmental factor that induces health problems in the general population. Due to ever increasing noise pollution, humans are facing multiple auditory and non-auditory problems including neuropsychiatric disorders. In modern day life it is impossible to avoid noise due to the rapid industrialization of society. Continuous exposure to noise stress creates a disturbance in brain function which may lead to memory disorder. Therefore, it is necessary to find preventive measures to reduce the deleterious effects of noise exposure. Supplementation of taurine, a semi essential amino acid, is reported to alleviate psychiatric disorders. In this study noise-exposed (100 db; 3 h daily for 15 days) rats were supplemented with taurine at a dose of 100 mg/kg for 15 days. Spatial and recognition memory was assessed using the Morris water maze and novel object recognition task, respectively. Results of this study showed a reversal of noise-induced memory impairment in rats. The derangements of catecholaminergic and serotonergic levels in the hippocampus and altered brain antioxidant enzyme activity due to noise exposure were also restored by taurine administration. This study highlights the importance of taurine supplementation to mitigate noise-induced impaired memory via normalizing the neurochemical functions and reducing oxidative stress in rat brain.

Free L-glutamate-induced modulation in oxidative and neurochemical profile contributes to enhancement in locomotor and memory performance in male rats.

Glutamate (Glu), the key excitatory neurotransmitter in the central nervous system, is considered essential for brain functioning and has a vital role in learning and memory formation. Earlier it was considered as a harmful agent but later found to be useful for many body functions. However, studies regarding the effects of free L-Glu administration on CNS function are limited. Therefore, current experiment is aimed to monitor the neurobiological effects of free L-Glu in male rats. L-Glu was orally administered to rats for 5-weeks and changes in behavioral performance were monitored. Thereafter, brain and hippocampus were collected for oxidative and neurochemical analysis. Results showed that chronic supplementation of free L-Glu enhanced locomotor performance and cognitive function of animals which may be attributed to the improved antioxidant status and cholinergic, monoaminergic and glutamatergic neurotransmission in brain and hippocampus. Current results showed that chronic supplementation of L-Glu affects the animal behaviour and brain functioning via improving the neurochemical and redox system of brain. Free L-Glu could be a useful therapeutic agent to combat neurological disturbances however this requires further targeted studies.

Amelioration of motor and non-motor deficits and increased striatal APoE levels highlight the beneficial role of pistachio supplementation in rotenone-induced rat model of PD.

Pistachio contains polyphenolic compounds including flavonoids and anthocyanins which have antioxidant and antiinflammatory activity. Present study was aimed to evaluate the protective effects of pistachio on neurobehavioral and neurochemical changes in rats with Parkinson's disease (PD). Animal model of PD was induced by the injection of rotenone (1.5 mg/kg/day, s.c.) for 8 days. Pistachio (800 mg/kg/day, p.o.) was given for two weeks in both pre- and post-treatment. At the end of treatment brain was dissected out and striatum was isolated for biochemical and neurochemical analysis. Memory was assessed by Morris water maze (MWM) and novel object recognition (NOR) test while open field test (OFT), Kondziela inverted screen test (KIST), pole test (PT), beam walking test (BWT), inclined plane test (IPT) and footprint (FP) test were used to observe motor behavior. Rotenone administration significantly (p < 0.01) impaired the memory but pistachio in both pre- and post-treatment groups significantly (p < 0.01) improved memory performance. Rotenone-induced motor deficits were significantly attenuated in both pre- and post-pistachio treatment. Increased oxidative stress and decreased DA and 5-HT levels induced by rotenone were also significantly attenuated by pistachio supplementation. Furthermore, raised apolipoprotein E (APoE) levels in rotenone injected rats were also normalized following treatment with pistachio. Present findings show that pistachio possesses neuroprotective effects and improves memory and motor deficits via increasing DA levels and improving oxidative status in brain.

Tree nuts supplementation instigates the oxidative status and improves brain performance in male rats.

Exposure to cadmium has been extensively increased due to its usage in modern daily life. Inside the human body it induces deteriorating effects in every vital organ including brain. Oxidative stress has been widely implicated in neurotoxicity induced by cadmium exposure. Consumption of dietary source of exogenous antioxidants is one of the recommended ways to extenuate heavy metal-induced oxidative stress. The potential of nuts against heavy-metal induced neurotoxicity has not been investigated earlier. This study was, therefore, conducted to find out the antioxidant ability of almond and walnut in the prevention of cadmium-induced oxidative stress. Rats were treated with nuts (400 mg/kg) daily for 28 days whereas, cadmium (50 mg/kg) was given once in a week. Brain function was monitored in terms of memory performance using Morris water maze and elevated plus maze. Moreover, oxidative stress status was also evaluated. Results showed that weekly exposure of cadmium significantly reduced %memory retention, increased lipid per oxidation and inhibited antioxidant enzymes activity. When nuts supplemented rats were monitored for these parameters, it was observed that almond and walnut have a great potential to reduce cadmium-induced neurotoxicity as evident by decreased oxidative stress and improved memory function in cadmium intoxicated rats.

Anxiolytic and memory enhancing potential of aloe vera and flax seed oil in rats: A comparative study with valproic acid.

For centuries, herbs and herbal oils are used for pharmacological purpose. Aloe vera is well-known as silent healer and flax seed oil is known to contain rich amount of omega-3 fatty acids, both are having effects on central nervous system. Valproic acid is anticonvulsant drug with some side effects and has shown effects on behaviors. This study was designed to monitor the effects of valproic acid, aloe vera and flax seed oil on cognitive and anxiolytic behaviors in rats. Animals were categorized into four groups: Control, valproic acid, aloe vera and flax seed oil which were respectively treated with water, valproic acid (300mg/kg), aloe vera (0.4ml/kg) and flax seed oil (1.8ml/kg). The treatment was continued 2 weeks for drug and 3 weeks for aloe vera and flax seed oil. Anxiolytic effect as well as increased GABA levels were observed following drug and oil treatments. Improvement in cognitive function with decrease in acetylcholine esterase activity in aloe vera and flax seed oil while impairment in learning memory with increase acetylcholine esterase activity was observed in rats treated with valproic acid. Results showed substantial decrease in acetylcholinesterase level in aloe vera and flax seed oil supporting the cognitive impact of oils in contrary to drug.

Spirulina platensis (Blue-green algae): A miracle from sea combats the oxidative stress and improves behavioral deficits in an animal model of Schizophrenia.

Spirulina platensis (blue-green algae) is a nutritional supplement. It constitutes of high content of protein, antioxidants, various phytopigments and possesses neuroprotective activities. Schizophrenia (SZ) is recognized as a neuropsychiatric disorder in humans with a reduced lifespan followed with impairments in social as well as vocational functioning. Major psychotic symptoms of SZ cluster into three categories: positive, negative and cognitive dysfunctions. Dizocilpine recognized as one of the best drugs to mimic full spectrum of SZ can develop an animal model of the disorder. Various antipsychotics are considered as approved treatment therapy for the psychotic symptoms of SZ but they also exert adverse effects. Thus, there is an excessive need for novel treatment(s) with negligible adverse effects. Present study was designed to evaluate the neuroprotective effects of spirulina in ameliorating the psychosis- like symptoms in dizocilpine-induced rat model of SZ. Spirulina was tested at the dose of 180 mg/kg. Results showed that administration of spirulina improved behavioral deficits and combated the oxidative damage evident by a significant reduction in lipid peroxidation and increase in antioxidant level. Thus, from present findings it may be suggested that spirulina can be used as a therapy for preventive or therapeutic measures.

Curcumin lessens unpredictable chronic mild stress-induced depression and memory deficits by modulating oxidative stress and cholinergic activity.

Unpredictable chronic mild stress (UCMS) model is the most established method to study neurobiological mechanisms of depression. This work was intended to explore the efficacy of curcumin to revert the UCMS-induced oxidative burden and associated depression as well as potential of curcumin as an acetyl cholinesterase (AchE) inhibitor. Animals were initially grouped into control and curcumin (200mg/kg, p.o) and further subdivided into unstressed and stressed groups. Depression and anxiety were evaluated by forced swim test (FST) and light/dark transition (LDT) while memory function was assessed by passive avoidance test (PAT). Effect of curcumin on oxidative stress following UCMS was determined by measuring peroxidation of lipid (LPO) and antioxidant enzyme activities. AchE activity was also determined. Findings showed that curcumin supplementation significantly attenuated the UCMS-induced depression and anxiety like symptoms, decreased the load of UCMS propagated oxidative stress by improving antioxidant enzymes activities. Curcumin also improved the memory function and exhibited inhibitory effect on AchE activity. In conclusion it can be suggested that supplementation of curcumin in daily life can help in combating the stress-induced depression and ever increasing load of oxidative stress. Study also highlights the anti-acetylcholinesterase potential of curcumin which may be responsible for improved memory function following UCMS.

Neurobehavioral and biochemical effects of magnesium chloride (MgCl2), magnesium sulphate (MgSO4) and magnesium-L-threonate (MgT) supplementation in rats: A dose dependent comparative study.

Magnesium (Mg) is an essential biomineral that acts as an intracellular cofactor for more than 300 enzymes. It is an important modulator of the N-methyl-D-aspartate (NMDA) receptor which is involved in memory function and depression. The purpose of this study was to compare the dose dependent effect of oral supplementation of Magnesium chloride (MgCl2), Magnesium sulphate (MgSO4) and Magnesium-L-threonate (MgT) on memory and depression-related behaviors in rats. Rats were orally administered with different doses (50 mg/kg, 100 mg/kg and 150 mg/kg) of each Mg salt. Following 28 days of oral supplementation, animals were subjected to behavioral tests. After completion of behavioral test, rats were decapitated. Brain and plasma samples were used for neurochemical and biochemical analysis. Assessment of behaviors in elevated plus maze (EPM) test and forced swim test (FST) showed that MgT more significantly improved memory of rats and decreased depression-like symptoms in healthy rats as compared to controls. Biochemical analysis indicated significant increase in plasma Mg levels dose dependently following MgT administration. This increase might be related to observe enhanced cholinergic functions and decline in oxidative stress in rats in the present study. This comparative study highlights that MgT (100mg/kg) is the most appropriate Mg salt and dose for oral treatment that strengthens cholinergic system and improves brain related functions through attenuation of oxidative burden in adult healthy rats.

Role of ibuprofen and lavender oil to alter the stress induced psychological disorders: A comparative study.

Stress has become an integral feature of everyday living. Each individual that lives encounters some manifestation of stress in life. Stress causes certain alterations in the structure and functions of the body and is considered to be a major factor in many health problems. Many synthetic and natural compounds are used for the attenuation of stress induced changes in the body. Medicinal plants are used since ancient times to prevent from neurological disorders. Lavender (Lavandula angustifolia) is very efficacious and possesses the ability to improve several neurological disorders. Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used against pain and inflammation. However, effectiveness of NSAIDs in the treatment of various psychiatric ailments is also reported. The present study investigated the effects of ibuprofen and lavender oil on stress induced behavioral and biochemical alterations in rats. The rats were subjected to restraint stress and behavioral parameters like open field test (OFT), light/dark transition box activity (LDT) and forced swim test (FST) were used to assess exploratory, anxiolytic and anti-depressant activity, respectively. Corticosterone, lipid peroxidation (LPO) and endogenous antioxidant enzymes activities were also estimated. Results of OFT, LDT and FST showed substantial effects of lavender oil and standard drug ibuprofen. A significant decrease in plasma corticosterone and LPO levels with increase in antioxidant enzyme activities was observed in the study. However, the effects of lavender oil were more as compared to standard drug ibuprofen in diminution of stress induced behavioral and biochemical changes in rats. This study demonstrates that lavender oil is more remedial than ibuprofen in stress related disorders.

Dietary Supplementation of Almond Prevents Oxidative Stress by Advocating Antioxidants and Attenuates Impaired Aversive Memory in Male Rats.

Scopolamine, an anti-muscarinic agent, has been shown to induce amnesia and oxidative stress similar to that observed in the older age. The present study was designed to determine the relationship between the oxidative status and memory improvement in scopolamine injected rats pre-administered with almonds. Rats (n = 8) in the almond group were administered orally with 400 mg/kg almond suspension for 28 days daily before the intraperitoneal injection of scopolamine (0.5 mg/kg). Passive avoidance task (PAT) was used to assess memory function at the end of treatment. The present study revealed that scopolamine injection significantly impaired the memory function in rats pre-treated with saline which was accompanied by increased oxidative stress as evident by increased brain malondialdehyde (MDA) levels and reduced activities of antioxidant enzymes as compared to healthy controls. Pre-treatment with almond significantly ameliorated scopolamine-induced oxidative stress and memory dysfunction. These findings suggest that dietary supplementation with almonds may have a beneficial effect in reducing the risk of oxidative stress-induced memory loss and delaying or preventing the onset of age-related memory impairment.

Enhancement of memory function by antioxidant potential of Nigella sativa L. oil in restrained rats.

Stress is a vulnerable state to cellular homeostasis which leads to oxidative damage via free radical generation. The acute stress induces alteration in antioxidant enzyme activities to an extent which produce oxidative stress and causes certain pathological conditions. The use of Nigella sativa L. oil (NSO) in folk medicine has increased throughout the world for the prevention or treatment of various ailments because of potent antioxidant properties. In the present study, potential therapeutic effects of NSO on memory in both unrestrained and 2h restrained rats were observed. Shortterm memory (STM) and long-term memory (LTM) were assessed by elevated plus maze (EPM) and Morris water maze (MWM) respectively. The present study also demonstrated the effect of NSO on lipid peroxidation (LPO) and activities of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) along with the activity of acetyl cholinesterase (AChE). The results obtained from the present study showed that 2h restraint stress significantly enhanced both short-term memory (p<0.01) and long-term memory (p<0.05) in rats. Pretreatment with NSO at a dose of 0.2ml/kg/day also significantly improved STM (p<0.05) in restrained rats and LTM (p<0.01) in unrestrained rats. This study also showed significantly decreased (p<0.01) LPO and significantly increased (p<0.01) endogenous antioxidant enzymes activity in NSO treated restrained rats. Similarly significant decreased (p<0.01) AChE activity was also observed in NSO treated unrestrained and 2h restrained rats. Therefore, current findings suggested that repeated administration of NSO may exert memory enhancing effects against restrained stress and it can be used for therapeutic purpose because of having fewer side effects.

Enhancement in spatial and recognition memory functions following long term oral administration of ginger extract in rats.

Ginger (Zingiber Officinale) is known over the centuries for its medicinal properties and has been used worldwide as health supplement and for treatment of several diseases. The purpose of this study was to evaluate the effects of whole ginger extract administration on spatial and recognition memory using experimental animal models. The antimicrobial properties of ginger extract against various pathogenic fungal and bacterial species were also examined. Aqueous extract of ginger at a dose of 500 mg/kg was orally administered to test rats and water was orally given to control rats for 6 weeks. Water Maze task (WM) was used to assess spatial memory and recognition memory of rats was evaluated by the Novel Object Recognition (NOR) task. Time spent with novel object was significantly increased in ginger treated rats as compared to control animals in novel object recognition task exhibiting enhanced recognition memory in ginger treated rats. Ginger treated rats exhibited significantly enhanced both short term memory and long term memory as evidenced by decrease in time to reach the hidden platform 1h and 24 h after training as compared to control rats. Short term memory functions of ginger treated rats were more enhanced than long term memory functions. Our findings suggest that ginger consumption may lead to an improvement in spatial and recognition memory. Significant activity of aqueous ginger extract was observed against pathogenic bacteria as well as fungal species. It is therefore suggested in this study that ginger extract can be used in microbial infections and as a memory enhancing drug in various memory disorders.

Attenuation of cadmium-induced decline in spatial, habituation and recognition memory by long-term administration of almond and walnut supplementation: Role of cholinergic function.

Excessive exposure of cadmium which is regarded as a neurotoxin can stimulate aging process by inducing abnormality in neuronal function. It has been reported that supplementation of almond and walnut attenuate age-related memory loss. Present study was designed to investigate the weekly administration of cadmium for one month on learning and memory function with relation to cholinergic activity. Cadmium was administered at the dose of 50 mg/kg/week. Whereas, almond and walnut was supplemented at the dose of 400 mg/kg/day along with cadmium administration to separate set of rats. At the end of experiment, memory function was assessed by Morris water maze, open field test and novel object recognition test. Results of the present study showed that cadmium administration significantly reduced memory retention. Reduced acetylcholine levels and elevated acetyl cholinesterase activity were also observed in frontal cortex and hippocampus of cadmium treated rats. Malondialdehyde levels were also significantly increased following the administration of cadmium. Daily supplementation of almond and walnut for 28 days significantly attenuated cadmium-induced memory impairment in rats. Results of the present study are discussed in term of cholinergic activity in cadmium-induced memory loss and its attenuation by nuts supplementation in rats.

Chronic choline supplementation improves cognitive and motor performance via modulating oxidative and neurochemical status in rats.

Choline, an essential nutrient, accounts for multiple functions in the body and brain. While its beneficial effects on healthy adults are not clear, choline supplementation is important during pregnancy for brain development, in elderly patients for support of cognitive performance and in patients with neurological disorders to reduce memory deficits. Thus, the aim of this study is to investigate whether choline administration in healthy adult rats beneficially impacts cognitive and locomotor performance, and associated oxidative and neurochemical outcomes. Two groups, control and choline, received tap water and choline bitartrate, respectively at the dose equivalent to adequate intake for five weeks. Food intake and body weight were monitored daily. Behavioral analysis comprising assessment of cognitive performance (by novel object recognition, passive avoidance and Morris Water Maze test) and locomotor performance (by Open field, Kondziela's inverted screen and beam walking test) were performed. Following testing, rats were decapitated and brain samples were collected for estimation of acetylcholine, redox profile and monoamine measurements. The results showed that chronic choline administration significantly improves cognitive and locomotor performance accompanied by a reduction in oxidative stress, enhanced cholinergic neurotransmission and monoamine levels in the brain of healthy adult rats. Hence, chronic choline intake was found to improve behavioral, oxidative and neurochemical outcomes in the normal population, so it can be suggested that choline tablets can be used as a safe and effective supplement for improving the neurological health of normal individuals and that they might also be beneficial in preventing cognitive and motor disorders later in life.

Impact of oral supplementation of Glutamate and GABA on memory performance and neurochemical profile in hippocampus of rats.

Glutamate (GLU) and gamma-amino butyric acid (GABA) are essential amino acids (AA) for brain function serving as excitatory and inhibitory neurotransmitter respectively. Their tablets are available in market for improving gut function and muscle performance. Despite of having a major role during memory formation and processing, effects of these tablets on brain functioning like learning and memory have not been investigated. Therefore, present study is aimed to investigate the effects of orally supplemented GLU and GABA on learning and memory performance and further to monitor related effects of these orally supplemented GLU and GABA on brain levels of these AA. Three groups of rats were supplemented orally with drinking water (control group) or suspension of tablets of GABA and Glutamate, respectively for four weeks. Cognitive performance was determined using behavioral tests (Novel object recognition test, Morris water maze, Passive avoidance test) measuring recognition, spatial reference and aversive memory. Levels of GLU, GABA and acetylcholine (ACh) were estimated in rat hippocampus. Results showed that chronic oral administration of GLU and GABA tablets has a significant impact on brain function and can alter GLU and GABA content in rat hippocampus. Compared to GABA, GLU supplementation specifically enhances memory performance via increasing ACh. Thus, GLU can be suggested as a useful supplement for improving learning and memory performance and neurochemical status of brain and in future could be effective in the treatment of neurological disorders affecting learning and memory performance.

Repeated administration of almonds increases brain acetylcholine levels and enhances memory function in healthy rats while attenuates memory deficits in animal model of amnesia.

Dietary nutrients may play a vital role in protecting the brain from age-related memory dysfunction and neurodegenerative diseases. Tree nuts including almonds have shown potential to combat age-associated brain dysfunction. These nuts are an important source of essential nutrients, such as tocopherol, folate, mono- and poly-unsaturated fatty acids, and polyphenols. These components have shown promise as possible dietary supplements to prevent or delay the onset of age-associated cognitive dysfunction. This study investigated possible protective potential of almond against scopolamine induced amnesia in rats. The present study also investigated a role of acetylcholine in almond induced memory enhancement. Rats in test group were orally administrated with almond suspension (400 mg/kg/day) for four weeks. Both control and almond-treated rats were then divided into saline and scopolamine injected groups. Rats in the scopolamine group were injected with scopolamine (0.5 mg/kg) five minutes before the start of each memory test. Memory was assessed by elevated plus maze (EPM), Morris water maze (MWM) and novel object recognition (NOR) task. Cholinergic function was determined in terms of hippocampal and frontal cortical acetylcholine content and acetylcholinesterase activity. Results of the present study suggest that almond administration for 28 days significantly improved memory retention. This memory enhancing effect of almond was also observed in scopolamine induced amnesia model. Present study also suggests a role of acetylcholine in the attenuation of scopolamine induced amnesia by almond.