Rhodiola crenulata and Its Bioactive Components, Salidroside and Tyrosol, Reverse the Hypoxia-Induced Reduction of Plasma-Membrane-Associated Na,K-ATPase Expression via Inhibition of ROS-AMPK-PKCξ Pathway

Figure 4

The protective effects of RCE, salidroside, and tyrosol are associated with alleviating the AMPK-PKCζ pathway under hypoxia. The cells were pretreated for 30 min with the indicated concentrations of Rhodiola products or chemicals under hypoxia (1% O₂) or normoxia for 24 h. The expressions of α1-Na,K-ATPase were analyzed in the presence or absence of RCE (a), salidroside (b), and tyrosol (c) in total cell lysate (TCL) under hypoxia or RCE (d), salidroside (e), and tyrosol (f) in both PM and TCL under normoxia. Cells were pretreated with RCE (15 μg/mL), salidroside (5.0 μM), or tyrosol (5.0 μM) for 30 min and then exposed to H₂O₂ (100 μM) for another 30 min under normoxia (g). AICAR (2 mM) was added in combination with RCE (15 μg/mL), salidroside (5.0 μM), or tyrosol (5.0 μM) (i). Compound C (2 μM) or GF10923X (1 μM) was preincubated alone prior to hypoxic exposure (k). (h), (j), and (l) are the quantitative data for the relative levels of α1-Na,K-ATPase in the PM from (g), (i), and (k). The results represent the mean ± SEM of three independent experiments. ^∗𝑃<0.05; ^∗∗𝑃<0.01; ^∗∗∗𝑃<0.001 versus control; ^#𝑃<0.05; ^##𝑃<0.01; ^###𝑃<0.001 versus hypoxia (H) or H₂O₂.

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

(i)

(j)

(k)

(l)