Diosgenin-Rich Yam Extract Enhances Cognitive Function: A Placebo-Controlled, Randomized, Double-Blind, Crossover Study of Healthy Adults
Abstract
:1. Introduction
2. Methods
2.1. Trial Design
2.2. Participants
2.3. Intervention
2.4. Outcomes and Assessments
2.5. Neurocognitive Assessments
2.6. Safety Assessment
2.7. Randomization
2.8. Animal Experiments: Animals and Materials
2.9. Animal Experiments: Object Recognition Test
2.10. Animal Experiments: Brain Penetration of Diosgenin after the Oral Administration of a Diosgenin-Rich Extract
2.11. Statistical Analysis
3. Results
3.1. Baseline Characteristics of the Study Groups
3.2. Neuropsychological Functioning
3.3. Safety Measures
3.4. Solubilization in Oil Facilitated Diosgenin Distribution in the Brain
4. Discussion
5. Limitations
6. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Values | |||
---|---|---|---|
n | Mean | SD | |
Subjects (Men/Women) | 28 (12/16) | ||
Age (years) | 46.50 | 18.67 | |
Race | Asian | ||
Educated period (years) | 16.29 | 2.37 | |
Estimated intelligence quotients (IQ) | 110.79 | 6.49 | |
MMSE-J | 29.39 | 1.03 | |
Total cholesterol (mg/dL) | 203.36 | 35.94 |
Cognitive Domain | Mean of Difference | SD of Difference | 95% CI | p Value |
---|---|---|---|---|
Total score (All) | 4.250 | 8.949 | 0.974 to 7.526 | 0.0129 * |
Total score (Men) | 4.750 | 9.087 | −1.023 to 10.520 | 0.0975 |
Total score (Women) | 3.875 | 8.221 | −5.056 to 8.256 | 0.0789 |
Total score (47–81 years) | 6.000 | 8.963 | 0.5838 to 11.420 | 0.0327 * |
Total score (60–81 years) | 6.556 | 8.691 | −0.125 to 13.240 | 0.0535 * |
Immediate memory | −1.107 | 16.900 | −7.659 to 5.445 | 0.7315 |
Visuospatial/Constructional | 2.536 | 12.960 | −2.489 to 7.560 | 0.3096 |
Language | 5.429 | 17.210 | −1.243 to 12.100 | 0.1066 |
Attention | 3.964 | 16.690 | −2.506 to 10.430 | 0.2194 |
Delayed memory | 3.393 | 14.860 | −2.369 to 9.154 | 0.2374 |
MMSE-J | −0.107 | 1.100 | −0.5337 to 0.3194 | 0.6105 |
Cognitive Domain | Subtest | Mean of Difference | SD of Difference | 95% CI | p Value |
---|---|---|---|---|---|
Immediate memory | List learning | 0.3214 | 3.1860 | −9.1410 to 1.5570 | 0.5978 |
Story memory | −0.6071 | 3.3260 | −1.8970 to 0.6825 | 0.3426 | |
Visuospatial/Constructional | Figure copy | 0.1071 | 2.1140 | −0.7126 to 0.9269 | 0.7906 |
Line orientation | 0.5000 | 2.4420 | −0.4469 to 1.4470 | 0.2882 | |
Language | Picture naming | 0.1429 | 2.0850 | −0.6658 to 0.9515 | 0.7198 |
Semantic fluency | 1.3210 | 3.1280 | 0.1087 to 2.5340 | 0.0338 * | |
Attention | Digit span | 1.1070 | 4.2720 | −0.5492 to 2.7640 | 0.1815 |
Digit symbol coding | 0.5357 | 3.3160 | −0.7503 to 1.8220 | 0.4002 | |
Delayed memory | List recall | 0.0714 | 3.4950 | −1.2840 to 1.4270 | 0.9147 |
List recognition | 0.0714 | 2.7070 | −0.9783 to 1.1210 | 0.8900 | |
Story recall | 0.3571 | 1.7890 | −0.3366 to 1.0510 | 0.3002 | |
Figure recall | 0.9643 | 3.2940 | −0.3130 to 2.2420 | 0.1330 |
Changed Values | |||||
---|---|---|---|---|---|
Placebo | Diosgenin-Rich Yam Extract | ||||
Mean | SD | Mean | SD | p Value | |
Total protein | −0.0393 | 0.3190 | 0.0464 | 0.3533 | 0.6102 |
Total cholesterol | −10.0000 | 22.9331 | 0.0357 | 25.1123 | 0.2765 |
HDL-cholesterol | −1.0357 | 13.3569 | 0.6786 | 8.9238 | 0.9651 |
Triglyceride | −13.8214 | 88.0980 | −36.4286 | 72.4980 | 0.0674 |
Glucose (non-fasting) | −3.2143 | 29.0496 | 12.2500 | 28.1644 | 0.1105 |
AST (GOT) | 1.4643 | 4.9026 | −0.7500 | 4.2828 | 0.3281 |
ALT (GPT) | 0.4643 | 5.4670 | −0.1429 | 4.2922 | 0.9946 |
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Share and Cite
Tohda, C.; Yang, X.; Matsui, M.; Inada, Y.; Kadomoto, E.; Nakada, S.; Watari, H.; Shibahara, N. Diosgenin-Rich Yam Extract Enhances Cognitive Function: A Placebo-Controlled, Randomized, Double-Blind, Crossover Study of Healthy Adults. Nutrients 2017, 9, 1160. https://doi.org/10.3390/nu9101160
Tohda C, Yang X, Matsui M, Inada Y, Kadomoto E, Nakada S, Watari H, Shibahara N. Diosgenin-Rich Yam Extract Enhances Cognitive Function: A Placebo-Controlled, Randomized, Double-Blind, Crossover Study of Healthy Adults. Nutrients. 2017; 9(10):1160. https://doi.org/10.3390/nu9101160
Chicago/Turabian StyleTohda, Chihiro, Ximeng Yang, Mie Matsui, Yuna Inada, Emika Kadomoto, Shotaro Nakada, Hidetoshi Watari, and Naotoshi Shibahara. 2017. "Diosgenin-Rich Yam Extract Enhances Cognitive Function: A Placebo-Controlled, Randomized, Double-Blind, Crossover Study of Healthy Adults" Nutrients 9, no. 10: 1160. https://doi.org/10.3390/nu9101160