OBJECTIVE: This study aimed to investigate the effect of turmeric (20mg/kg) on learning and memory and cholinergic system in a mouse model of stress along with cholinergic blockade.
METHODS: Restrained stress was induced and cholinergic receptors were blocked using scopolamine in mice. Animals were treated with turmeric (turmeric rhizome powder which was also subjected to NMR analyses) and learning and social behavior was examined. Effect of turmeric on cholinergic muscarinic receptors (mAChR; M1, M3 and M5) gene expression was assessed by RT-PCR in both pre-frontal cortex and hippocampus.
RESULTS: Ar-turmerone, curcuminoids and α-linolenic acid were the lead compounds present in turmeric extract. Increased serum corticosterone levels were observed in stressed mice when compared to the control group, while turmeric treatment significantly reduced serum corticosterone level. Turmeric treatment caused an improved learning and memory in Morris water maze test in stressed animals. Social novelty preference was also restored in turmeric treated animals. Following turmeric treatment, M5 expression was improved in the cortex and M3 expression was improved in the hippocampus of stress + scopolamine + turmeric treated group.
CONCLUSIONS: These findings highlight the therapeutic role of turmeric by increasing the expression of M3, M5 and improving learning and memory. Turmeric can be an effective candidate for the treatment of amnesia caused by the stress.
METHODS: Galactagogue activity was evaluated in terms of quantity of milk produced from the rats treated with petroleum ether, ethanol or water extracts of the flower. Lactating rats (n = 5) of Spraque Dawley with six pups each were administered with the extracts in the amount of 500 mg/kg body weight, while the control rats were given an equivalent amount of distilled water. The rats were daily administered via oral feeding starting from Day 5 until Day 14 and the performance of milk production was measured along the experimental period by weight-suckle-weight method. Results were statistically analyzed using SPSS by means of ANOVA at 0.05 and was expressed as their mean?standard deviation. The rates of pups' growth were measured as the weight gain along the experimental period.
RESULTS: The rats treated with aqueous extract produced higher milk than control and ethanol groups. Aqueous extract was identified to increase milk production by 25%, while petroleum ether extract by 18%. The mean of yields produced by the rats during suckling period for aqueous, petroleum ether, ethanol and control were 4.62±2.45, 4.37±1.93, 3.65±1.89 and 3.69±1.79, respectively. Growth rates of pups for the rats treated with control, aqueous, ethanol extract and petroleum ether were (1.85±0.49), (1.78±0.56), (1.65±0.46) and (1.56±0.42) g/pup, respectively.
CONCLUSIONS: The present study reveals the potential of M. x paradisiaca flower to enhance milk production of nursing mothers which could be exploited for commercialization of the isolated extract.