Effects of Flavonoids from <i>Potamogeton crispus</i> L. on Proliferation, Migration, and Invasion of Human Ovarian Cancer Cells

<div><p>In order to explore the efficient utilization of plant resources from constructed wetlands, the potential anti-metastatic effects of flavonoids from <i>Potamogeton crispus </i>L. were investigated in human ovarian cancer cells (ES-2). Two major flavonoids, luteolin-3ʹ-O-β-D-glucopyranoside and flavone-6-C-β-D-glucopyranoside, were isolated from <i>P</i>. <i>crispus</i> and identified. The effects of these flavonoids on cell proliferation, cell morphology, cell cycle, apoptosis, and cell migration and invasion were then investigated. Furthermore, reverse transcriptase polymerase chain reaction assays and western blotting analysis were conducted to examine the expression level of mRNA and protein. Results indicated that Luteolin-3ʹ-O-β-D-glucopyranoside inhibited ES-2 cell migration and invasion and suppressed the expression of two matrix metalloproteinases (MMPs), MMP-2 and MMP-9, and Flavone-6-C-β-D-glucopyranoside had no significant inhibitory effects on ES-2 cells. Thus, this study demonstrated the potential anti-metastatic properties of a <i>P</i>. <i>crispus</i> flavonoid, and provided a scientific approach for the screening of promising natural resources from constructed wetlands to identify useful products for use in the pharmaceutical and healthcare industries.</p></div

Two-way analysis of different factors.

<p>^a. Depths = 0–15 cm and 15–25 cm.</p><p>^b. Locations = upstream and downstream locations.</p><p>^c. Types = river wetland and constructed wetland.</p><p>Results with significant differences (<i>p</i> < 0.05) were shown in bold.</p><p>Two-way analysis of different factors.</p

The spatial and vertical distribution of heavy fraction organic carbon (HFOC).

<p>Bar plots showing the spatial and vertical (0–15 cm vs. 15–25 cm) distribution of heavy fraction organic carbon (HFOC) in the Xinxue River (XR) and Xinxue River Constructed Wetland (XRCW). A = upstream location of XRCW; B = downstream location of XRCW; C = upstream location of XR; D = downstream location of XR. Bars sharing the same letter are not significant at α = 0.05 (Duncan Test).</p

The spatial distribution of dissolved organic carbon (DOC).

<p>Bar plots showing the spatial distribution of dissolved organic carbon (DOC) in the Xinxue River (XR) and Xinxue River Constructed Wetland (XRCW). A = upstream location of XRCW; B = downstream location of XRCW; C = upstream location of XR; D = downstream location of XR. Bars sharing the same lowercase letter (a or b) are not significant at α = 0.05 (Duncan Test).</p

Luteolin-3′-O-β-d-glucopyranoside (LU3′O-GP) reduced mRNA expression of MMP-2 and MMP-9 in ES-2 cells.

<p>(a) LU3′O-GP effects on MMP-2 expression; (b) LU3′O-GP effects on MMP-9 expression. mRNA levels were investigated by reverse transcriptase polymerase chain reaction (RT-PCR), using glyceraldehyde 3-phosphate dehydrogenase as the loading control. RT-PCR products were detected by ethidium bromide staining. Values represent the means of triplicate experiments. *<i>p</i> < 0.05, as compared to the control.</p

The spatial distribution of light fraction organic carbon (LFOC).

<p>Bar plots showing the spatial distribution of light fraction organic carbon (LFOC) in the Xinxue River (XR) and Xinxue River Constructed Wetland (XRCW). A = upstream location of XRCW; B = downstream location of XRCW; C = upstream location of XR; D = downstream location of XR. Bars sharing the same lowercase letter (a or b) are not significant at α = 0.05 (Duncan test).</p

Chemical structure of two <i>P</i>. <i>crispus</i> flavonoids

<p>Chemical structure of two <i>P</i>. <i>crispus</i> flavonoids</p

Two-way analysis of different factors.

<p>^a. Depths = 0–15 cm and 15–25 cm.</p><p>^b. Locations = upstream and downstream locations.</p><p>^c. Types = river wetland and constructed wetland.</p><p>Results with significant differences (<i>p</i> < 0.05) were shown in bold.</p><p>Two-way analysis of different factors.</p

Pearson correlation analysis among the factors in Xinxue River Constructed Wetland.

<p>** Correlation is significant at the 0.01 level (2-tailed).</p><p>* Correlation is significant at the 0.05 level (2-tailed).</p><p>Pearson correlation analysis among the factors in Xinxue River Constructed Wetland.</p

<i>P</i>. <i>crispus</i> flavonoid effects on cell cycle progression in ES-2 cells.

<p>(a) Negative control; (b) cells treated with 100 μg/mL flavone-6-C-β-d-glucopyranoside (FL6C-GP); (c) cells treated with 30 μg/mL luteolin-3′-O-β-d-glucopyranoside (LU3′O-GP); and (d) cells treated with 60 μg/mL LU3′O-GP. Cells were fixed with ethanol and stained with propidium iodide prior to cell cycle distribution analysis by flow cytometry. The number of cells in G0/G1 phase is represented by the first peak, and those in G2/M phase are represented by the second peak. Cells in S phase are present in the area between the G0/G1 and G2/M peaks. These data represent the mean of triplicate experiments. * <i>p <</i> 0.01 as compared with control.</p