Oral administration of 6-methylsulfinylhexyl isothiocyanate extracted from wasabi is safe and improves the fatigue and sleep of healthy volunteers

Ryota Nakajima; Masanobu Kanou; Masahiko Tokushima; Yoshitaka Iwama; Kei Yamana

doi:10.1186/s13030-023-00287-0

Oral administration of 6-methylsulfinylhexyl isothiocyanate extracted from wasabi is safe and improves the fatigue and sleep of healthy volunteers

Biopsychosoc Med. 2023 Aug 23;17(1):30. doi: 10.1186/s13030-023-00287-0.

Authors

Ryota Nakajima^{1

2}, Masanobu Kanou^{3

4}, Masahiko Tokushima⁵, Yoshitaka Iwama⁶, Kei Yamana^{3

4}

Affiliations

¹ Nutraceutical Group, Division of New Business in Healthcare Business, Teijin Ltd., 2-1, Kasumigaseki 3-chome, Chiyoda-ku, Tokyo, 100-8585, Japan. r.nakajima@teijin.co.jp.
² NOMON Co., Ltd, Tokyo, Japan. r.nakajima@teijin.co.jp.
³ Nutraceutical Group, Division of New Business in Healthcare Business, Teijin Ltd., 2-1, Kasumigaseki 3-chome, Chiyoda-ku, Tokyo, 100-8585, Japan.
⁴ NOMON Co., Ltd, Tokyo, Japan.
⁵ Maebashi North Hospital, Maebashi, Japan.
⁶ Nihonbashi Cardiology Clinic, Tokyo, Japan.

Abstract

Background: This study aimed to conduct a preliminary evaluation of the effects of 6-methylsulfinylhexyl isothiocyanate (6-MSITC) contained in wasabi rhizomes on fatigue and sleep and to examine its safety through overdose study.

Methods: A total of 20 healthy volunteers who were experiencing daily fatigue were given powder containing 6-MSITC (4.8 mg/day of 6-MSITC) extracted from wasabi for 4 weeks. Then, fatigue, sleep, autonomic nervous functioning, stress, and immunity were evaluated. In addition, an overdose safety study of the extract powder (up to 16 mg/day of 6-MSITC for 4 weeks) was performed with 30 healthy volunteers in a double-blind, placebo-controlled method.

Results: The powder containing 6-MSITC did not improve fatigue after a mental task, but fatigue before the mental task, sleep, and mood were improved significantly after 4 weeks intake. No changes were observed in the autonomic nerve function, stress, or immune markers. In the overdose safety study, no changes in the parameters or side effects were observed, and the results showed that high doses of the extract powder containing 6-MSITC is safe.

Conclusion: This study confirmed the possibility that this powder extracted from wasabi that contains 6-MSITC might improve fatigue and sleep. However, because the effectiveness evaluation in this study was a single-arm, open-label study and there was no placebo control group, these points must be considered when interpreting the results. Safety was confirmed in an overdose study of more than three times the amount compared to that in the efficacy evaluation study. In the future, further research should be conducted on its effectiveness for treating fatigue and sleep problems.

Trial registration: UMIN clinical trial registration system, UMIN000049913. Registered 27 December 2022 Retrospectively registered, https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000056818.

Keywords: 6-MSITC; Clinical study; Fatigue; Safety study; Sleep; Wasabi extract powder.