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Ding J, Yu M, Jiang J, Luo Y, Zhang Q, Wang S, Yang F, Wang A, Wang L, Zhuang M, Wu S, Zhang Q, Xia Y, Lu D. Angiotensin II Decreases Endothelial Nitric Oxide Synthase Phosphorylation via AT 1R Nox/ROS/PP2A Pathway. Front Physiol 2020; 11:566410. [PMID: 33162896 PMCID: PMC7580705 DOI: 10.3389/fphys.2020.566410] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 09/08/2020] [Indexed: 12/12/2022] Open
Abstract
Increasing evidences suggest that angiotensin (Ang) II participates in the pathogenesis of endothelial dysfunction (ED) through multiple signaling pathways, including angiotensin type 1 receptor (AT1R) mediated NADPH oxidase (Nox)/reactive oxygen species (ROS) signal transduction. However, the detailed mechanism is not completely understood. In this study, we reported that AngII/AT1R-mediated activated protein phosphatase 2A (PP2A) downregulated endothelial nitric oxide synthase (eNOS) phosphorylation via Nox/ROS pathway. AngII treatment reduced the levels of phosphorylation of eNOS Ser1177 and nitric oxide (NO) content along with phosphorylation of PP2Ac (PP2A catalytic subunit) Tyr307, meanwhile increased the PP2A activity and ROS production in human umbilical vein endothelial cells (HUVECs). These changes could be impeded by AT1R antagonist candesartan (CAN). The pretreatment of 10−8 M PP2A inhibitor okadaic acid (OA) reversed the levels of eNOS Ser1177 and NO content. Similar effects of AngII on PP2A and eNOS were also observed in the mesenteric arteries of Sprague-Dawley rats subjected to AngII infusion via osmotic minipumps for 2 weeks. We found that the PP2A activity was increased, but the levels of PP2Ac Tyr307 and eNOS Ser1177 as well as NO content were decreased in the mesenteric arteries. The pretreatments of antioxidant N-acetylcysteine (NAC) and apocynin (APO) abolished the drop of the levels of PP2Ac Tyr307 and eNOS Ser1177 induced by AngII in HUVECs. The knockdown of p22phox by small interfering RNA (siRNA) gave rise to decrement of ROS production and increment of the levels of PP2Ac Tyr307 and eNOS Ser1177. These results indicated that AngII/AT1R pathway activated PP2A by downregulating its catalytic subunit Tyr307 phosphorylation, which relies on the Nox activation and ROS production. In summary, our findings indicate that AngII downregulates PP2A catalytic subunit Tyr307 phosphorylation to activate PP2A via AT1R-mediated Nox/ROS signaling pathway. The activated PP2A further decreases levels of eNOS Ser1177 phosphorylation and NO content leading to endothelial dysfunction.
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Affiliation(s)
- Jing Ding
- Department of Pathophysiology, Guizhou Medical University, Guiyang, China.,Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, China
| | - Min Yu
- Department of Pathophysiology, Guizhou Medical University, Guiyang, China.,Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, China
| | - Juncai Jiang
- Department of Pathophysiology, Guizhou Medical University, Guiyang, China.,Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, China
| | - Yanbei Luo
- Department of Pathophysiology, Guizhou Medical University, Guiyang, China.,Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, China
| | - Qian Zhang
- Department of Pathophysiology, Guizhou Medical University, Guiyang, China.,Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, China
| | - Shengnan Wang
- Department of Pathology, The Second Clinical Medical School of Inner Mongolia University for the Nationalities, Yakeshi, China
| | - Fei Yang
- Department of Cardiology, The Second Provincial People's Hospital of Gansu, Lanzhou, China
| | - Alei Wang
- Department of Pathophysiology, Guizhou Medical University, Guiyang, China.,Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, China
| | - Lingxiao Wang
- Department of Pathophysiology, Guizhou Medical University, Guiyang, China.,Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, China
| | - Mei Zhuang
- Department of Cardiology, Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Shan Wu
- Department of Neurology, Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Qifang Zhang
- Key Laboratory of Medical Molecular Biology, Guizhou Medical University, Guiyang, China
| | - Yong Xia
- Davis Heart and Lung Research Institute, The Ohio State University College of Medicine, Columbus, OH, United States
| | - Deqin Lu
- Department of Pathophysiology, Guizhou Medical University, Guiyang, China.,Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, China
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Ishii Y, Yokoo Y, Kijima A, Takasu S, Ogawa K, Umemura T. DNA modifications that do not cause gene mutations confer the potential for mutagenicity by combined treatment with food chemicals. Food Chem Toxicol 2019; 129:144-152. [PMID: 31029721 DOI: 10.1016/j.fct.2019.04.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 04/04/2019] [Accepted: 04/08/2019] [Indexed: 01/10/2023]
Abstract
Cell proliferation plays a key role in fixing mutations induced by DNA damage. We clarified whether this phenomenon occurred after combined treatment with chemicals in food. The effects of antibiotic flumequine (FL), a residue of veterinary medicinal products in foodstuffs, on mutagenicity in the liver were examined in mice treated with estragole (ES), a natural food flavouring compound. Gpt delta mice were orally administered 10 or 100 mg/kg/day ES and simultaneously fed a diet containing 0.4% FL for 4 weeks. Proliferating cell nuclear antigen-positive cells and cell cycle-related genes were additively increased in the livers of combined treatment groups as compared with high-dose ES or FL groups. Mutant frequencies (MFs) in gpt after cotreatment with low-dose ES and FL were significantly increased, although treatment with ES alone increased MFs only in the high-dose group. Sult1a1 mRNA levels were unchanged after FL treatment. Liquid chromatography with tandem-mass spectrometry analysis showed that FL did not affect the amount of ES-specific DNA adducts in the livers, indicating that FL treatment did not influence metabolic pathways of ES. Thus, enhancement of the mutagenic potential of a chemical by chemical-induced cell proliferation may occur as a result of the combined effects of chemicals in food.
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Affiliation(s)
- Yuji Ishii
- Division of Pathology, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-shi, Kawasaki-ku, Kanagawa, 210-9501, Japan
| | - Yuh Yokoo
- Division of Pathology, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-shi, Kawasaki-ku, Kanagawa, 210-9501, Japan
| | - Aki Kijima
- Division of Pathology, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-shi, Kawasaki-ku, Kanagawa, 210-9501, Japan
| | - Shinji Takasu
- Division of Pathology, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-shi, Kawasaki-ku, Kanagawa, 210-9501, Japan
| | - Kumiko Ogawa
- Division of Pathology, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-shi, Kawasaki-ku, Kanagawa, 210-9501, Japan
| | - Takashi Umemura
- Division of Pathology, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-shi, Kawasaki-ku, Kanagawa, 210-9501, Japan; Faculty of Animal Health Technology, Yamazaki University of Animal Health Technology, 4-7-2, Minami-osawa, Hachihoji, Tokyo, 192-0364, Japan.
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