Abstract
This pilot study tested the effects of the supplements containing water chestnut extract and carotenoids on antiglycation and carotenoid levels. Twenty Japanese subjects (mean age, 67 ± 7 years; 13 men) ingested 200 mg of Tarpa bispinosa Roxb. extract (containing >50 mg of polyphenols), 20 mg of lutein, and 3 mg of zeaxanthin daily for 3 months. Advanced glycation end product (AGEs) levels were estimated by fingertip skin autofluorescence using the AGEs Sensor; carotenoid levels were estimated by pressure-mediated reflection spectroscopy of the fingertips using the Veggie Meter. Compared to baseline, the mean AGEs score decreased significantly (0.55 ± 0.04 arbitrary units (AU) vs. 0.52 ± 0.07 AU, p = 0.03); the mean carotenoid score increased significantly (256 ± 68 optical density (OD) vs. 302 ± 109 OD, p = 0.02) at 3 months. Blood pressure, body weight, visual acuity, refractive error, and intraocular pressure were equivalent between baseline and 3 months. Compared to baseline, 13 (65%) patients had decreased AGEs scores, and 14 (70%) had increased carotenoid scores at 3 months; 9 (45%) subjects had both decreased AGEs scores and increased carotenoid scores, and two (10%) subjects had an inverse response. Co-administration of water chestnut extract and lutein for 3 months decreased the AGEs and increased the carotenoids estimated in the fingertip skin of humans.
Acknowledgments
The tested supplements were provided by Santen Pharmaceuticals (Osaka, Japan).
IRB statement
The study adhered to the tenets of the Declaration of Helsinki; the IRB of Shimane University Hospital reviewed and approved the research (IRB No. 20200805-1; 28 September 2020). The study was registered in UMIN (ID: UMIN000041756) before start of the study.
Informed consent statement
All subjects provided written informed consent.
Author contributions
Conceptualization, M.T.; methodology, A.O. and M.T.; formal analysis, Y.Y. and M.T.; investigation, Y.Y., M.M., S.I., Y.T., A.I., and M.T.; data curation, Y.Y. and M.T.; writing—original draft preparation, Y.Y. and M.T.; writing—review and editing, M.M., S.I., Y.T., A.I., and A.O. All authors have read and agreed to the published version of the manuscript.
Disclosure statement
Masaki Tanito received lecture fees, consultant fees, and research donations from Santen Pharmaceutical Co., Ltd. The supplements were provided from Santen Pharmaceutical Co., Ltd. for research purpose. The company had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. Other authors report no conflicts of interest in this work.
Data availability statement
Data are fully available upon reasonable request to corresponding author.