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.

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.

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.

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.