Milind Parle

Brahmi rasayana Improves Learning and Memory in Mice

Cure of cognitive disorders such as amnesia, attention deficit and Alzheimers disease is still a nightmare in the field of medicine. Nootropic agents such as piracetam, aniracetam and choline esterase inhibitors like Donepezil® are being used to improve memory, mood and behavior, but the resulting side effects associated with these agents have made their use limited. The present study was undertaken to assess the potential of Brahmi rasayana (BR) as a memory enhancer. BR (100 and 200 mg kg−1 p.o.) was administered for eight successive days to both young and aged mice. Elevated plus maze and passive-avoidance paradigm were employed to evaluate learning and memory parameters. Scopolamine (0.4 mg kg−1 i.p.) was used to induce amnesia in mice. The effect of BR on whole brain AChE activity was also assessed. Piracetam (200 mg kg−1 i.p.) was used as a standard nootropic agent. BR significantly improved learning and memory in young mice and reversed the amnesia induced by both scopolamine (0.4 mg kg−1 i.p.) and natural aging. BR significantly decreased whole brain acetyl cholinesterase activity. BR might prove to be a useful memory restorative agent in the treatment of dementia seen in elderly.

Improvement of mouse memory by Myristica fragrans seeds.

Memory is one of the most complex functions of the brain and involves multiple neural pathways and neurotransmitter systems. The present study was undertaken to investigate the effect of Myristica fragrans (MF) seeds on learning and memory in mice. The n-hexane extract of MF was administered orally in three doses (5, 10, and 20 mg/kg p.o.) for 3 successive days to different groups of young and aged mice. The learning and memory parameters were assessed using elevated plus-maze and passive-avoidance apparatus. The effect of MF extract on scopolamine (0.4 mg/kg i.p.)- and diazepam (1 mg/kg i.p.)-induced impairment in learning and memory was also studied. MF extract at the lowest dose of 5 mg/kg p.o. administered for 3 successive days significantly improved learning and memory of young and aged mice. This extract also reversed scopolamine- and diazepam-induced impairment in learning and memory of young mice. MF extract enhanced learning and retention capacities of both young and aged mice. The exact mechanism of the memory-improving effect of MF extract was not explored in the present study. But, the observed memory-enhancing effect may be attributed to a variety of properties (individually or in combination) the plant is reported to possess, such as antioxidant, anti-inflammatory, or perhaps procholinergic activity.

Antiamnesic potential of Murraya koenigii leaves

Murraya koenigii leaves commonly known as curry patta are added routinely to Indian gravy and vegetarian dishes as a favorite condiment. The effects of Murraya koenigii leaves (MKL) on cognitive functions, total serum cholesterol level and brain cholinesterase activity in young and aged mice fed orally with a diet containing 2%, 4% and 8% w/w of MKL for 30 days consecutively, were investigated. The memory scores were measured using various exteroceptive and interoceptive behavioral models. The MKL diets produced a significant dose‐dependent improvement in the memory scores of young and aged mice and significantly reduced the amnesia induced by scopolamine (0.4 mg/kg, i.p.) and diazepam (1 mg/kg, i.p.). Also, brain cholinesterase activity and total cholesterol levels were reduced by the MKL diets. The underlying mechanism of action for the observed nootropic effect may be attributed to pro‐cholinergic activity and a cholesterol lowering property. Therefore, it would be worthwhile to investigate specifically the therapeutic potential of MKL in the management of Alzheimer patients. Copyright

Reversal of memory deficits by Coriandrum sativum leaves in mice

BACKGROUND Coriandrum sativum L., commonly known as coriander and belonging to the family Apiaceae (Umbelliferae), is cultivated throughout the world for its nutritional value. The present study was undertaken to investigate the effects of fresh Coriandrum sativum leaves (CSL) on cognitive functions, total serum cholesterol levels and brain cholinesterase activity in mice. In this study, CSL (5, 10 and 15% w/w of diet) was fed orally with a specially prepared diet for 45 days consecutively to experimental animals. Elevated plus-maze and passive avoidance apparatus served as the exteroceptive behavioral models for testing memory. Diazepam, scopolamine and ageing-induced amnesia served as the interoceptive behavioral models. RESULTS CSL (5, 10 and 15% w/w of diet) produced a dose-dependent improvement in memory scores of young as well as aged mice. CSL also reversed successfully the memory deficits induced by scopolamine (0.4 mg kg(-1), i.p.) and diazepam (1 mg kg(-1), i.p.). Interestingly, brain cholinesterase activity and serum total cholesterol levels were considerably reduced by CSL administration in daily diets concomitantly for 45 days. CONCLUSION CSL may be a useful remedy in the management of Alzheimers disease on account of its multifarious effects such as, memory-improving property, cholesterol-lowering property and anticholinesterase activity.

Protective effects of total alkaloidal extract from Murraya koenigii leaves on experimentally induced dementia.

Dementia is a syndrome of gradual onset and continuous decline of higher cognitive functioning. It is a common disorder in older persons and has become more prevalent today. The fresh leaves of Murraya koenigii are often added to various dishes in Asian countries due to the delicious taste and flavor that they impart. These leaves have also been proven to have health benefits. In the present study, the effect of total alkaloidal extract from M. koenigii leaves (MKA) on cognitive functions and brain cholinesterase activity in mice were determined. In vitro β-secretase 1 (BACE1) inhibitory activity was also evaluated. The total alkaloidal extract was administered orally in three doses (10, 20 and 30 mg/kg) for 15 days to different groups of young and aged mice. Elevated plus maze and passive avoidance apparatus served as the exteroceptive behavioral models for testing memory. Diazepam-, scopolamine-, and ageing-induced amnesia served as the interoceptive behavioral models. MKA (20 and 30 mg/kg, p.o.) showed significant improvement in memory scores of young and aged mice. Furthermore, the same doses of MKA reversed the amnesia induced by scopolamine (0.4 mg/kg, i.p.) and diazepam (1 mg/kg, i.p.). Interestingly, the brain cholinesterase activity was also reduced significantly by total alkaloidal extract of M. koenigii leaves. The IC50 value of MKA against BACE1 was 1.7 μg/mL. In conclusion, this study indicates MKA to be a useful remedy in the management of Alzheimers disease and dementia.

Soybean supplementation helps reverse age- and scopolamine-induced memory deficits in mice.

Phytoestrogens are nonsteroidal plant compounds that are able to exert estrogenic effects. Soybean is a rich source of phytoestrogens, especially isoflavones. Soy isoflavones are utilized for estrogen replacement therapy. Estrogen is reported to influence several areas of brain that are involved in cognition and behavior. Therefore, the present study was undertaken to examine whether dietary supplementation with soybean improves the cognitive function of mice. Soybean was administered in three different concentrations (2%, 5% and 10% [wt/wt]) in the normal diet to young and mature mice for 60 successive days. The passive avoidance paradigm and the elevated plus maze served as the exteroceptive behavioral models, whereas scopolamine (1.4 mg/kg, i.p.) served as the interoceptive behavioral model. The brain acetylcholinesterase activity (AChE) activity, brain thiobarbituric acid-reactive substances (TBARS), reduced glutathione (GSH), and total blood cholesterol levels were also measured in the present study. The administration of soybean for 60 consecutive days protected (P < .05) the animals from developing memory impairment. Soybean administration also resulted in diminished brain AChE activity, decrease in brain TBARS, and increase in GSH levels, thereby indicating facilitated cholinergic transmission, reduced free radical generation, and enhanced scavenging of free radicals. Thus, soybean appears to be a useful remedy for improving memory and for the management of cognitive deficits owing to its pro-estrogenic, antioxidant, procholinergic, and/or neuroprotective properties.

Memory-Enhancing Activity of Thespesia populnea. in Rats

Abstract Thespesia populnea. Soland ex. Correa (Malvaceae) is a large tree found in the tropical regions and coastal forests of India. Various parts of Thespesia populnea. are found to possess useful medicinal properties such as antifertility, antibacterial, anti-inflammatory, antioxidant, purgative, and hepatoprotective activities. The current study was undertaken to investigate the effects of Thespesia populnea. bark on memory in rats. Elevated plus-maze and Hebb-Williams maze served as the exteroceptive behavioral models for testing memory. Diazepam-, scopolamine-, and ageing-induced amnesia served as the interoceptive behavioral models. The ethanol extract of Thespesia populnea. (TPE) was administered orally in three doses (100, 200, and 400 mg/kg) for 7 successive days to different groups of young and aged rats. TPE (200 and 400 mg/kg, p.o.) resulted in significant improvement in memory of young and aged rats. TPE also reversed the amnesia induced by scopolamine (0.4 mg/kg, i.p.) and diazepam (1 mg/kg, i.p.). Cholesterol-lowering, anticholinesterase, anti-inflammatory, and antioxidant properties of Thespesia populnea. may favorably contribute to its memory-enhancement effect. Therefore, Thespesia populnea. bark appears to be a promising candidate for improving memory, and it would be worthwhile to explore the potential of this plant in the management of Alzheimer patients.

Antiamnesic Activity of an Ayurvedic Formulation Chyawanprash in Mice

Chyawanprash (Chy) is an ayurvedic formulation commonly consumed in Indian households. Chy is a comprehensive herbal tonic, prepared from around 50 herbs employing anwala (Emblica officinalis) as the basic ingredient. The present study was undertaken to explore the beneficial effects of Chy (at the dose of 1 and 2% w/w of diet) administered daily for 15 successive days in mice with memory deficits. A total of 228 mice divided in 38 groups were employed in this study. Morris water maze, Hebb-Williams maze and elevated plus maze served as exteroceptive memory models, whereas scopolamine (Sco)-induced amnesia and alprazolam (Alp)-induced amnesia served as interoceptive memory models. The brain acetylcholinesterase activity, brain thiobarbituric acid reactive substances (TBARS) and reduced glutathione levels (GSH) were also estimated. The administration of Chy for 15 consecutive days significantly protected the animals from developing memory impairment. Furthermore, there was a significant decrease in brain TBARS and increase in GSH levels after administration of Chy (2% w/w), thereby indicating decreased free radical generation and increased scavenging of free radical, respectively. Thus, Chy may prove to be a useful remedy for the management of Alzheimers disease owing to its antioxidant effect, pro-cholinergic action and/or antiamnesic potential.

Hypolipidemic and weight reducing activity of the ethanolic extract of Tamarindus indica fruit pulp in cafeteria diet- and sulpiride-induced obese rats

Objectives: To investigate the effect of ethanolic extract of fruit pulp of Tamarindus indica Linn. (Family: Caesalpiniaceae) on obesity in rats using cafeteria diet-induced obesity and antipsychotic drug (sulpiride)-induced obesity. Materials and Methods: Cafeteria dietwas administered for 40 successive days to male Wistar rats and sulpiride (20 mg/kg, i.p.) was administered for 28 successive days to female Wistar rats. In separate groups of animals, the ethanolic extract (50 and 100 mg/kg p.o.) of Tamarindus indica fruit was administered along with cafeteria diet for 40 successive days to Wistar male rats and along with sulpiride for 28 successive days to Wistar female rats. Results: Cafeteria diet alone significantly increased body weight, serum total cholesterol, triglycerides, and glucose levels and decreased HDL cholesterol in male rats as compared to control. Sulpiride per se significantly increased the levels of glucose, triglycerides, cholesterol and there was no significant effect on HDL-cholesterol in female rats as compared to control. Ethanolic extract showed a significant decrease in body weight, serum cholesterol, and triglycerides and a significant increase in HDL-cholesterol in cafeteria diet- and sulpiride-induced obese rats as compared to their respective control groups. Conclusions: Thus, the ethanolic extract of Tamarindus indica fruit pulp showed a significant weight-reducing and hypolipidemic activity in cafeteria diet- and sulpiride-induced obese rats.

Potential drug targets and treatment of schizophrenia

Schizophrenia is one of the most prevalent chronic psychiatric disorders that affect 1% of the world’s population. Despite its societal burden, pathophysiology of schizophrenia remains poorly understood. Currently available drugs predominantly control positive symptoms, and often have no or poor control on negative and related cognitive symptoms, which strongly affect functional outcome in schizophrenia. The present article is an attempt to provide a critical review of recent hypothesis to understand pathophysiology of schizophrenia and to highlight exploitable molecular drug targets other than dopaminergic systems to treat and manage schizophrenia effectively.