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Long term administration of loquat leaves and their major component, ursolic acid, attenuated endogenous amyloid-β burden and memory impairment.

ABSTRACT: Loquat (Eriobotrya japonica) leaves contain many bioactive components such as ursolic acid (UA) and amygdalin. We investigated the effects of loquat leaf powder and methanol extract in human neuroglioma H4 cells stably expressing the Swedish-type APP695 (APP_NL-H4 cells) and C57BL/6 J mice. Surprisingly, the extract greatly enhanced cellular amyloid-beta peptide (Aβ) 42 productions in APP_NL-H4 cells. Administration of leaf powder increased Aβ42 levels after 3 months and decreased levels after 12 months compared to control mice. Leaf powder had no effect on working memory after 3 months, but improved working memory after 12 months. Administration of UA decreased Aβ42 and P-tau levels and improved working memory after 12 months, similar to the administration of leave powder for 12 months. Amygdalin enhanced cellular Aβ42 production in APP_NL-H4 cells, which was the same as the extract. Three-month administration of amygdalin increased Aβ42 levels slightly but did not significantly increase them, which is similar to the trend observed with the administration of leaf powder for 3 months. UA was likely the main compound contained in loquat leaves responsible for the decrease in intracerebral Aβ42 and P-tau levels. Also, amygdalin might be one of the compounds responsible for the transiently increased intracerebral Aβ42 levels.

SUBMITTER: Iwasa K

PROVIDER: S-EPMC10556093 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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Long term administration of loquat leaves and their major component, ursolic acid, attenuated endogenous amyloid-β burden and memory impairment.

Iwasa Kensuke K Yagishita Sosuke S Yagishita-Kyo Nan N Yamagishi Anzu A Yamamoto Shinji S Yamashina Kota K Haruta Chikara C Asai Masashi M Maruyama Kei K Shimizu Kuniyoshi K Yoshikawa Keisuke K

Scientific reports 20231005 1

Loquat (Eriobotrya japonica) leaves contain many bioactive components such as ursolic acid (UA) and amygdalin. We investigated the effects of loquat leaf powder and methanol extract in human neuroglioma H4 cells stably expressing the Swedish-type APP695 (APP<sub>NL</sub>-H4 cells) and C57BL/6 J mice. Surprisingly, the extract greatly enhanced cellular amyloid-beta peptide (Aβ) 42 productions in APP<sub>NL</sub>-H4 cells. Administration of leaf powder increased Aβ42 levels after 3 months and decr ...[more]

PMID: 37798424

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Dataset Information

Long term administration of loquat leaves and their major component, ursolic acid, attenuated endogenous amyloid-β burden and memory impairment.

Publications

Long term administration of loquat leaves and their major component, ursolic acid, attenuated endogenous amyloid-β burden and memory impairment.

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