PMC

Ginger oleoresin induced nucleus translocation of Nrf2 in hMSCs when treated with ionizing radiation. (a) hMSCs when not treated or treated with ginger oleoresin alone or treated with ionizing radiation alone or pretreated with ginger oleoresin and then with ionizing radiation were stained with TRITC-labelled anti-Nrf2 antibody and DAPI. Nrf2-TRITC (left), DAPI (mid), merge (right) are shown. (b) Distribution of Nrf2 in the cytoplasm or nucleus in hMSCs. When pretreated with ginger oleoresin and then ionizing radiation, Nrf2 in the nucleus was increased.

Ginger oleoresin reduced the IR-induced DNA strand breaks in hMSCs. The levels of DNA strand breaks were assayed by comet assay. (a) Representative micrographs—(A): untreated group; (B): treated with ginger oleoresin only; (C): treated with IR only; and (D): pretreated with ginger oleoresin and then with IR. (b) Tail DNA%. (c) Tail length. (d) Tail moment. Results are expressed as mean ± SD (n = 4). ^∗p < 0.05 IR versus untreated control (Ctrl). ^#p < 0.05 ginger oleoresin + IR versus IR.

Ginger oleoresin increased the cell viability and reduced the γ-ray irradiation-induced ROS level in hMSCs. Cell viability was measured using the MTT assay (a). The level of ROS was measured using DCF fluorescence with a fluorescence microscope (b) and flow cytometry (c). Cells were untreated (Ctrl) or treated with ginger oleoresin (10⁻⁴ g/mL) (Trt) and γ-ray irradiation (4 Gy) (IR) or pretreated with ginger oleoresin (10⁻⁴ g/mL) and then γ-ray irradiation (4 Gy) (Trt + IR). Results are expressed as mean ± SD (n = 4). ^∗p < 0.05 IR versus untreated control (Ctrl). ^#p < 0.05 Trt + IR versus IR.

Knocking down Nrf2 reversed the radiation protective effect of ginger oleoresin on hMSCs. Results are expressed as mean ± SD (n = 5). ^∗∗p < 0.01.