Elaeagnus umbellata leaves have been reported to suppress
inflammation, allergic responses, lung cancer proliferation and oral bacterial
growth. Cadmium (Cd) is a heavy metal that has been found to cause many
toxicities, including liver toxicity. The aim of this study was to evaluate the
capacity of 70% ethanol extract of E. umbellata leaves
(EUL) to protect human hepatocytes from Cd toxicity. After exposure of HepG2
cells to Cd at 10 μM for 24 h, cell viability,
expression levels of apoptosis- and antioxidant-related proteins,
reactive oxygen species (ROS) accumulation and Cd uptake were assessed. EUL
protected HepG2 cells from Cd-induced apoptosis as determined by MTT assay. A
decrease in caspase-3 and p-p53 protein levels was observed in cells pretreated
with EUL prior to Cd exposure. Furthermore, the Cd-induced increase in
intracellular DCF fluorescence was attenuated by EUL, indicating that the
Cd-induced apoptosis preventing effect was associated with the suppression of
ROS accumulation. Moreover, EUL’s effects on the inhibition of p38, JNK,
and AKT phosphorylation also appear to be associated with protection against Cd
toxicity. Moreover, EUL upregulated Cd-depressed expression of Nrf2, HO-1,
catalase, and MT-1,2 proteins, suggesting that Cd uptake-induced apoptosis in
HepG2 cells may be inhibited by EUL’s antioxidative potential.