UMIN-CTR Clinical Trial

Basic information
Official scientific title of the study	Effects of the extract of Dioscorea batatas on cognitive functions in healthy adults
Title of the study (Brief title)	Effects of the extract of Dioscorea batatas on cognitive functions in healthy adults
Region	Japan

Condition
Condition	Healthy adults
Classification by specialty	Not applicable Adult
Classification by malignancy	Others
Genomic information	NO

Objectives
Narrative objectives1	Investigation of cognitive functions at pre and post(3 months after) administration of the extract of Dioscorea batatas.
Basic objectives2	Efficacy
Basic objectives -Others
Trial characteristics_1
Trial characteristics_2
Developmental phase

Assessment
Primary outcomes	At pre and post (for 3 months) administration of the extract of Dioscorea batatas, these tests of cognitive functions are done; Mini Mental State Examination (MMSE)and Repeatable Battery for the Assessment(RBANS)
Key secondary outcomes	analysis of the blood

Base
Study type	Interventional

Study design
Basic design	Cross-over
Randomization	Randomized
Randomization unit	Individual
Blinding	Double blind -all involved are blinded
Control	Placebo
Stratification
Dynamic allocation
Institution consideration
Blocking
Concealment

Intervention
No. of arms	2
Purpose of intervention	Treatment
Type of intervention	Food
Interventions/Control_1	Treatment A - wash out - Treatment B Tretament A: Intake of capsules containing the extract of Dioscorea batatas. 25 mg extract/capsule (= 4 mg diosgenin/capsule), two capsules per day, for 3 months Treatment B:Intake of capsules without the extract of Dioscorea batatas. two capsules per day, for 3 months
Interventions/Control_2	Treatment B - wash out - Treatment A Tretament A: Intake of capsules containing the extract of Dioscorea batatas. 25 mg extract/capsule (= 4 mg diosgenin/capsule), two capsules per day, for 3 months Treatment B:Intake of capsules without the extract of Dioscorea batatas. two capsules per day, for 3 months
Interventions/Control_3
Interventions/Control_4
Interventions/Control_5
Interventions/Control_6
Interventions/Control_7
Interventions/Control_8
Interventions/Control_9
Interventions/Control_10

Eligibility
Age-lower limit	20 years-old <=
Age-upper limit	85 years-old >=
Gender	Male and Female
Key inclusion criteria	Healthy human psychologically and physically living in Toyama prefecture, who volunteers to attend this clinical study. Subjects have no food allergy against Dioscorea rhizome (Yam).
Key exclusion criteria	Subjects who have visited the hospital due to forgetfulness or memory dysfunction. Subjects who have food allergy against Dioscorea rhizome (Yam).
Target sample size	41

Research contact person
Name of lead principal investigator	Chihiro Tohda
Organization	University of Toyama
Division name	Division of Neuromedical Science, Institute of Natural Medicine
Address	2630 Sugitani, Toyama, 930-0194, JAPAN
TEL	076-434-7646
Email	chihiro@inm.u-toyama.ac.jp

Public contact
Name of contact person	Chihiro Tohda
Organization	University of Toyama
Division name	Division of Neuromedical Science, Institute of Natural Medicine
Address	2630 Sugitani, Toyama, 930-0194, JAPAN
TEL	076-434-7646
Homepage URL
Email	chihiro@inm.u-toyama.ac.jp

Sponsor
Institute	University of Toyama
Institute
Department

Funding Source
Organization	University of Toyama
Organization
Division
Category of Funding Organization	Other
Nationality of Funding Organization	Japan

Other related organizations
Co-sponsor
Name of secondary funｄer(s)

Secondary IDs
Secondary IDs	NO
Study ID_1
Org. issuing International ID_1
Study ID_2
Org. issuing International ID_2
IND to MHLW

Institutions
Institutions	国立大学法人　富山大学

Other administrative information
Date of disclosure of the study information	2016 Year 02 Month 28 Day

Progress
Recruitment status	Completed
Date of protocol fixation	2016 Year 01 Month 29 Day
Anticipated trial start date	2016 Year 03 Month 01 Day
Last follow-up date	2016 Year 11 Month 30 Day
Date of closure to data entry	2016 Year 12 Month 20 Day
Date trial data considered complete	2017 Year 01 Month 18 Day
Date analysis concluded	2017 Year 03 Month 31 Day

Related information
URL releasing protocol
Publication of results	Published
URL releasing results	https://www.mdpi.com/2072-6643/9/10/1160
Results	Diosgenin-rich yam extract consumption for 12 weeks yielded significant increases in total RBANS score. Among the 12 individual standard cognitive subtests, diosgenin-rich yam extract use significantly improved the semantic fluency. No adverse effects were reported. The diosgenin-rich yam extract treatment appeared to safely enhance cognitive function in healthy adults.
Other related information

Management information
Registered date	2016 Year 02 Month 23 Day
Last modified on	2019 Year 02 Month 25 Day

Link to view the page
URL(English)	https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000024399