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ABSTRACT: ABSTRACT The loss of sex hormones in postmenopausal women has been suggested to be involved in cognitive degenerative diseases, such as Alzheimer's disease. In the present study, ovariectomized (OVX) and control rats were tested for 4 months in a Morris water maze (MWM) task to track their memory status. Thereafter, postmortem frozen brain sections were analyzed to determine if changes in brain area volumes and neuronal density were related to changes in cognitive ability. A modified artificial-land-mark-based method was used to assure the fidelity of the three dimensions (3D) reconstructed structures. Volumetric areas of the hippocampus, cortex, caudate putamen (cpu), and cerebellum were estimated from the reconstructions, and neuron densities of CA1 and CA3 subregions of the hippocampus were measured in an adjacent second series of Nissl-stained sections. Compared to the control rats, OVX rats displayed memory impairments, beginning in the second month after the ovariectomy (p < .05). Assessments at the end of the study demonstrated that OVX (compared to control) rats displayed reduced brain volume in the hippocampus and neocortex and in the brain as a whole. In contrast, when compared to controls, the volumes of cpu and cerebellum of OVX rats increased slightly. CA3 neuron density of OVX (compared to controls) rats was significantly lower, but the CA1 neuron density was significantly higher. In conclusion, ovariectomy impaired spatial memory and led to morphological changes in cognitive centers of rat brain. The results demonstrate that the 3D reconstructed method is useful for the study of brain morphological abnormality in rats.
The International journal of neuroscience 05/2012; 122(10):549-59. · 0.86 Impact Factor
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ABSTRACT: Curcuma comosa is widely used as a traditional herbal medicine for gynecological diseases in South East Asia. Previous studies reported that it has phytoestrogenic activity, and several diarylheptanoids were found to be the active constituents. In this study, the pharmacokinetics profile and organ distribution of three active compounds of C. comosa hexane extract were investigated. Rats were separately administered C. comosa hexane extract intravenously at the dose of 125 mg/kg and orally at the doses of 125 and 250 mg/kg body weight, after which blood and target organs were collected at specified time intervals from 0 to 24 h. HPLC was used to measure the concentration of three major compounds, (6E)-1,7-diphenylhept-6-en-3-one (DPH1), (4E,6E)-1,7-diphenylhepta-4,6-dien-3-ol (DPH2), and (6E)-1,7-diphenylhept-6-en-3-ol (DPH3), which were found to be present in the blood and tissues and were subsequently used as markers. In the intravenous study, the volumes of distribution (V(d)) were 1.06, 8.57, and 6.56 L/kg and clearance values (CL(s)) were 0.28, 5.56, and 3.39 L/kg/h for DPH1, DPH2, and DPH3, respectively. After oral administration, the three major compounds of both doses reached a maximum systemic concentration at 2 h with maximum concentration (C(max)) of 0.85, 0.17, and 0.53 mg/L for the lower dose and 1.46, 0.17, and 0.61 mg/L for the higher dose. The bioavailabilities were 31.2, 24.01, and 31.56% for lower dose and 22.61, 17.66, and 17.73% for higher dose with a terminal half-life (t(1/2)) of 10.86, 6.3, and 4.62 h for lower dose and 3.85, 2.77, and 2.10 h for higher dose for DPH1, DPH2, and DPH3, respectively. These three major compounds are all found distributed in the brain, liver, kidneys, ovaries, and uterus after oral and intravenous administration and their related pharmacokinetic parameters are described. This study provides the essential pharmacokinetic data for diarylheptanoid phytoestrogenic compounds of C. comosa extract which are required for clinical dose and dosage design.
Journal of Natural Medicines 11/2011; 66(3):468-75. · 1.39 Impact Factor
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ABSTRACT: Curcuma comosa was reported to have uterotrophic effects in ovariectomized (OVX) rats. The present study aims to investigate the plant estrogenic-like effects of C. comosa hexane extract on spatial memory and estrogen receptors (ER) in the hippocampus. Female rats received 5 days' Morris water maze training before the ovariectomy, followed by the daily intraperitoneal administration of C. comosa hexane extract at a dose of 250 and 500 mg/kg body weight for 4 weeks. Estradiol (10 μg/kg body weight) was used as the positive control. OVX significantly increased the latency of the animal to the platform, while estradiol and both doses of C. comosa hexane extract reversed the memory impairments. By using the reverse transcription polymerase chain reaction technique, C. comosa hexane extract was shown to produce a selective increase of the ER alpha subtype but not beta subtype in hippocampus, while estradiol increased both of them. C. comosa did not affect spatial memory, learning ability, and ER mRNA levels in the sham OVX rats. In conclusion, C. comosa hexane extract improved the spatial memory of the OVX rats, which was similar to estrogen. The influence on the memory changes might be selectively related to ER alpha in the hippocampus.
Journal of Natural Medicines 01/2011; 65(1):57-62. · 1.39 Impact Factor
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ABSTRACT: Curcuma comosa extract and some purified compounds from this plant have been reported to have estrogenic-like effects, and estrogen improves learning in some animals and potentially in postmenopausal women; therefore, this study tested the hypothesis that Curcuma comosa and estrogen have similar beneficial effects on spatial learning and memory.
Curcuma comosa hexane extract, containing 0.165 mg of (4E,6E)-1,7-diphenylhepta-4,6-dien-3-one per mg of the crude extract, was orally administered to ovariectomized Wistar rats at the doses of 250 or 500 mg/kg body weight. 17beta-estradiol (10 microg/kg body weight, subcutaneously) was used as a positive control. Thirty days after the initiation of treatment, animals were tested in a Morris water maze for spatial learning and memory. They were re-tested every 30 days and a final probe trial was run on day 119.
Compared to control rats, OVX rats displayed significant memory impairment for locating the platform in the water maze from day 67 after the surgery, onward. In contrast, OVX rats treated with either Curcuma comosa or estrogen were significantly protected from this decline in cognitive function. Further, the protection of cognitive effects by Curcuma comosa was larger at higher dose.
These results suggest that long-term treatment with Curcuma comosa has beneficial effects on learning and memory function in rats.
Journal of ethnopharmacology 07/2010; 130(1):70-5. · 2.32 Impact Factor