Protective Effect of Lemon Peel Extract on Oxidative Stress in H9c2 Rat Heart Cell Injury

Abstract

Jun Wang,1,2 Yulin Zhai,1 Mingguang Ou,3 Yunfeng Bian,4 Chenglong Tang,5 Wanchao Zhang,6– 8 Yujiao Cheng,1,2 Guijie Li1,2 1Citrus Research Institute, Southwest University, Chongqing, People’s Republic of China; 2National Citrus Engineering Research Center, Chongqing, People’s Republic of China; 3Guang’an Nongfeng Agricultural Development Co., Ltd, Sichuan, People’s Republic of China; 4Guang’an Zheng Wang Agriculture Co., Ltd, Sichuan, People’s Republic of China; 5Yuanyang Hongtu Grapefruit Agricultural Technology Development Co., Ltd, Yunnan, People’s Republic of China; 6Chongqing Institute of Medicinal Plant Cultivation, Chongqing, People’s Republic of China; 7National Patent Navigation Project (Chongqing) Research and Promotion Center, Chongqing, People’s Republic of China; 8Bio-Resource Research and Utilization Joint Key Laboratory of Sichuan and Chongqing, Chongqing, People’s Republic of ChinaCorrespondence: Wanchao Zhang Tel [phone]Email [email protected] Li 15# Ganjucun, Xiema, Beibei District, Chongqing, 400712, People’s Republic of ChinaTel [phone]Email [email protected]: Lemon peel, a traditional Chinese medicine, was tested in this study for its novel application in inhibiting cellular oxidative stress, and the effect of lemon peel extract (LPE) on protecting H9c2 rat heart cells from oxidative stress was investigated.Methods: The scavenging effects of LPE on 1,1-diphenyl-2-picryhydrazyl (DPPH) and 2,2’-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) free radicals were measured in extracellular experiments. The 3-(4,5-dimethyl-2-thiazolinyl)-2,5-diphenyl-2-h-tetrazolylammonium bromide (MTT) assay was used to detect the cell survival rate. The cell supernatant and intracellular oxidation-related indicators were detected by a kit, and the mRNA expression in H9c2 cells was detected by quantitative polymerase chain reaction (qPCR). The chemical substances of LPE were analyzed by high-performance liquid chromatography (HPLC).Results: The results showed that LPE exhibited better DPPH and ABTS free radical scavenging abilities than vitamin C. Compared with the cells in the normal state (control group), the cell survival rate in the model group decreased, and the level of lactate dehydrogenase (LDH) increased, the levels of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) decreased, and the content of malondialdehyde (MDA) increased. Compared with the control group, the expression of Bcl-2-related X protein (Bax), caspase-3, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) in the model group was increased, and the expression of B-cell lymphoma-2 (Bcl-2) was reduced. Compared with the model group, LPE treatment improved the cell survival rate, reduced the levels of LDH and MDA, increased the levels of SOD, CAT, and GSH, downregulated the expression of Bax, caspase-3, Nrf2 and HO-1, and upregulated the expression of Bcl-2. The composition analysis showed that LPE contained catechin, rutin, naringin, quercetin, and hesperidin.Conclusion: The results indicated that LPE could protect H9c2 cells from oxidative stress through five active components. LPE has the potential to be developed into natural medicine or health food for the inhibition of cell oxidative damage.Keywords: lemon peel, oxidative stress, H9c2 rat heart cell, mRNA expression, HPLC

Keywords

• lemon peel
• oxidative stress
• h9c2 rat heart cell
• mrna expression
• hplc