Hydroxysafflor Yellow A Blocks HIF-1<i>α</i> Induction of NOX2 and Protects ZO-1 Protein in Cerebral Microvascular Endothelium
Yi Li,
Xiao-Tian Liu,
Pei-Lin Zhang,
Yu-Chen Li,
Meng-Ru Sun,
Yi-Tao Wang,
Sheng-Peng Wang,
Hua Yang,
Bao-Lin Liu,
Mei Wang,
Wen Gao,
Ping Li
Affiliations
Yi Li
State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, No. 24 Tongjia Lane, Nanjing 210009, China
Xiao-Tian Liu
State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, No. 24 Tongjia Lane, Nanjing 210009, China
Pei-Lin Zhang
State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, No. 24 Tongjia Lane, Nanjing 210009, China
Yu-Chen Li
State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, No. 24 Tongjia Lane, Nanjing 210009, China
Meng-Ru Sun
State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, No. 24 Tongjia Lane, Nanjing 210009, China
Yi-Tao Wang
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau 999078, China
Sheng-Peng Wang
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau 999078, China
Hua Yang
State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, No. 24 Tongjia Lane, Nanjing 210009, China
Bao-Lin Liu
State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, No. 24 Tongjia Lane, Nanjing 210009, China
Mei Wang
Leiden University-European Center for Chinese Medicine and Natural Compounds, Institute of Biology/SU BioMedicine, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands
Wen Gao
State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, No. 24 Tongjia Lane, Nanjing 210009, China
Ping Li
State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, No. 24 Tongjia Lane, Nanjing 210009, China
Zonula occludens-1 (ZO-1) is a tight junction protein in the cerebrovascular endothelium, responsible for blood–brain barrier function. Hydroxysafflor yellow A (HSYA) is a major ingredient of safflower (Carthamus tinctorius L.) with antioxidative activity. This study investigated whether HSYA protected ZO-1 by targeting ROS-generating NADPH oxidases (NOXs). HSYA administration reduced cerebral vascular leakage with ZO-1 protection in mice after photothrombotic stroke, largely due to suppression of ROS-associated inflammation. In LPS-stimulated brain microvascular endothelial cells, HSYA increased the ratio of NAD+/NADH to restore Sirt1 induction, which bound to Von Hippel–Lindau to promote HIF-1αdegradation. NOX2 was the predominant isoform of NOXs in endothelial cells and HIF-1α transcriptionally upregulated p47phox and Nox2 subunits for the assembly of the NOX2 complex, but the signaling cascades were blocked by HSYA via HIF-1α inactivation. When oxidate stress impaired ZO-1 protein, HSYA attenuated carbonyl modification and prevented ZO-1 protein from 20S proteasomal degradation, eventually protecting endothelial integrity. In microvascular ZO-1 deficient mice, we further confirmed that HSYA protected cerebrovascular integrity and attenuated ischemic injury in a manner that was dependent on ZO-1 protection. HSYA blocked HIF-1α/NOX2 signaling cascades to protect ZO-1 stability, suggestive of a potential therapeutic strategy against ischemic brain injury.
