Ehretiquinone from Onosma bracteatum Wall Exhibits Antiaging Effect on Yeasts and Mammals through Antioxidative Stress and Autophagy Induction

Abstract

The antiaging benzoquinone-type molecule ehretiquinone was isolated in a previous study as a leading compound from the herbal medicine Onosma bracteatum wall. This paper reports the antiaging effect and mechanism of ehretiquinone by using yeasts, mammal cells, and mice. Ehretiquinone extends not only the replicative lifespan but also the chronological lifespan of yeast and the yeast-like chronological lifespan of mammal cells. Moreover, ehretiquinone increases glutathione peroxidase, catalase, and superoxide dismutase activity and reduces reactive oxygen species and malondialdehyde (MDA) levels, contributing to the lifespan extension of the yeasts. Furthermore, ehretiquinone does not extend the replicative lifespan of Δsod1, Δsod2, Δuth1, Δskn7, Δgpx, Δcat, Δatg2, and Δatg32 mutants of yeast. Crucially, ehretiquinone induces autophagy in yeasts and mice, thereby providing significant evidence on the antiaging effects of the molecule in the mammalian level. Concomitantly, the silent information regulator 2 gene, which is known for its contributions in prolonging replicative lifespan, was confirmed to be involved in the chronological lifespan of yeasts and participates in the antiaging activity of ehretiquinone. These findings suggest that ehretiquinone shows an antiaging effect through antioxidative stress, autophagy, and histone deacetylase Sir2 regulation. Therefore, ehretiquinone is a promising molecule that could be developed as an antiaging drug or healthcare product.

A New Geniposidic Acid Derivative Exerts Antiaging Effects through Antioxidative Stress and Autophagy Induction

“…Replicative lifespan assays were performed following a previous method [ 20 ]. In brief, the K6001 yeast strain was collected from a −30 °C freezer after washing with PBS thrice, inoculated in galactose liquid medium (YPG, 1% yeast extract, 2% hipolypeptone, and 3% galactose), and cultured with shaking at 28 °C and 180 rpm for 24 h. After the yeast cells reached the logarithmic growth phase, 4000 yeast cells were inoculated in glucose solid medium (YPD, 2% glucose, 2% hipolypeptone, 1% yeast extract, and 2% agar), which was added with samples in advance and incubated at 28 °C for 48 h. Forty mother cells were randomly selected under the microscope, and surrounding daughter cells were counted.…”

“…The chronological lifespan assay was conducted as described in our previous study [ 20 ]. In brief, the YOM36 yeast strain was collected from a −30 °C freezer and washed with PBS, and about 200 yeast cells were inoculated in glucose solid medium and cultured at 28 °C for 48 h in the stationary phase.…”

“…The antioxidative stress assay was performed as described in our previous study [ 20 ]. For the antioxidant qualitative test, the BY4741 yeast strain in glucose liquid medium with an initial 0.1 OD 600 value was treated with GENI (0,1, and 3 µM) or RES (positive control, 10 µM) and cultured with shaking at 28 °C and 180 rpm for 24 h. From each group, 5 µL of yeast medium was inoculated in glucose solid medium with 9.5 mM H 2 O 2 and cultured at 28 °C for 48 or 72 h. The growth of the yeast was observed and recorded.…”

“…ROS was measured as described in our previous study [ 20 ]. In brief, the BY4741 yeast strain in glucose liquid medium treated with 0, 1, and 3 µM GENI or 10 µM RES was cultured with shaking at 28 °C and 160 rpm for 12 h. Each group was washed with PBS, added with 2′,7′-dichloro-dihydrofluorescein diacetate fluorescent probes to a final concentration at 10 µM, incubated for 1 h with shaking in the dark, and washed with PBS.…”

“…The MDA was measured as described in our previous study [ 20 ]. In brief, the BY4741 yeast strain in glucose liquid medium treated with 0, 1, and 3 µM GENI or 10 µM RES was cultured with shaking at 28 °C and 160 rpm for 12 h, washed with PBS, sonicated on ice for 5 min for protein extraction, and centrifuged at 4 °C and 12,000 rpm for 10 min to obtain the supernatant as protein samples.…”