The effects of icariin on the expression of HIF-1α, HSP-60 and HSP-70 in PC12 cells suffered from oxygen–glucose deprivation-induced injury

Abstract

Context: The effects of icariin, a chief constituent of flavonoids from Epimedium brevicornum Maxim (Berberidaceae), on the levels of HIF-1α, HSP-60 and HSP-70 remain unknown.

Objective: To explore the effects of icariin on the levels of HSP-60, HIF-1α and HSP-70 neuron-specific enolase (NSE) and cell viability.

Materials and methods: PC12 cells were treated with icariin (10⁻⁷, 10⁻⁶ or 10⁻⁵mol/L) for 3 h (1 h before oxygen–glucose deprivation (OGD) plus 2 h OGD). HSP-60, HIF-1α, HSP-70 and NSE were measured using enzyme-linked immunosorbent assay (ELISA). Cell viability was determined by metabolic 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.

Results: After 2 h OGD, levels of HIF-1α, HSP-60, HSP-70 and NSE were increased significantly (HIF-1α: 33.3 ± 1.9 ng/L, HSP-60: 199 ± 16 ng/L, HSP-70: 195 ± 17 ng/L, NSE: 1487 ± 125 ng/L), and cell viability was significantly decreased (0.26 ± 0.03), while icariin (10⁻⁷, 10⁻⁶, or 10⁻⁵mol/L) significantly reduced the contents of HIF-1α, HSP-60, HSP-70 and NSE (HIF-1α: 14.1 ± 1.4, 22.6 ± 1.8, 15.7 ± 2.1, HSP-60: 100 ± 12, 89 ± 6, 113 ± 11, HSP-70: 139 ± 9, 118 ± 7, 95 ± 9 and NSE: 1121 ± 80, 1019 ± 52, 731 ± 88), and improved cell viability (0.36 ± 0.03, 0.38 ± 0.04, 0.37 ± 0.03) in OGD-treated PC12 cells.

Discussion and conclusion: These results indicate that the protective mechanisms of icariin against OGD-induced injury may be related to down-regulating the expression of HIF-1α, HSP-60 and HSP-70.

Keywords:

• Heat shock protein
• neuron-specific enolase
• cell viability

Acknowledgements

This work was supported by the National Natural Science Foundation of China (NO 31360212), Guizhou Science and Technology Foundation of China (NO LKZ[2013]04), Guizhou Science and Technology Foundation of China (NO QKHJ[2014]2180) and Premier-Discipline Enhancement Scheme of Pharmacology Supported by Zhuhai Government Fund.

Disclosure statement

The authors have no conflicts of interest in this study. Zhen-tao MO and Shu-ying GAO designed the research; Zhen-tao MO, Wen-na LI and Yu-rong ZHAI performed the research; Zhen-tao MO analyzed the data and wrote the paper.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (NO 31360212), Guizhou Science and Technology Foundation of China (NO LKZ[2013]04), Guizhou Science and Technology Foundation of China (NO QKHJ[2014]2180) and Premier-Discipline Enhancement Scheme of Pharmacology Supported by Zhuhai Government Fund.