{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T05:24:25Z","timestamp":1768281865536,"version":"3.49.0"},"reference-count":42,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2017,4,7]],"date-time":"2017-04-07T00:00:00Z","timestamp":1491523200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31372486"],"award-info":[{"award-number":["31372486"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Olaquindox, a feed additive, has drawn public attention due to its potential mutagenicity, genotoxicity, hepatoxicity and nephrotoxicity. The purpose of this study was to investigate the role of tuberous sclerosis complex (TSC2) pathways in olaquindox-induced autophagy in human embryonic kidney 293 (HEK293) cells. The results revealed that olaquindox treatment reduced the cell viability of HEK293 cells and downregulated the expression of TSC2 in a dose- and time-dependent manner. Meanwhile, olaquindox treatment markedly induced the production of reactive oxygen species (ROS), cascaded to autophagy, oxidative stress, and apoptotic cell death, which was effectively eliminated by the antioxidant N-acetylcysteine (NAC). Furthermore, overexpression of TSC2 attenuated olaquindox-induced autophagy in contrast to inducing the production of ROS, oxidative stress and apoptosis. Consistently, knockdown of TSC2 upregulated autophagy, and decreased olaquindox-induced cell apoptosis. In conclusion, our findings indicate that TSC2 partly participates in olaquindox-induced autophagy, oxidative stress and apoptosis, and demonstrate that TSC2 has a negative regulation role in olaquindox-induced autophagy in HEK293 cells.<\/jats:p>","DOI":"10.3390\/molecules22040595","type":"journal-article","created":{"date-parts":[[2017,4,7]],"date-time":"2017-04-07T10:49:53Z","timestamp":1491562193000},"page":"595","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["TCS2 Increases Olaquindox-Induced Apoptosis by Upregulation of ROS Production and Downregulation of Autophagy in HEK293 Cells"],"prefix":"10.3390","volume":"22","author":[{"given":"Daowen","family":"Li","sequence":"first","affiliation":[{"name":"College of Veterinary Medicine, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kena","family":"Zhao","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiayun","family":"Yang","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xilong","family":"Xiao","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shusheng","family":"Tang","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,4,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1017","DOI":"10.2174\/1573406411309080002","article-title":"The Metabolism of Carbadox, Olaquindox, Mequindox, Quinocetone and Cyadox: An Overview","volume":"9","author":"Liu","year":"2013","journal-title":"Med. Chem."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"328","DOI":"10.1016\/j.fct.2008.11.020","article-title":"Investigation of the genotoxicity of quinocetone, carbadox and olaquindox in vitro using Vero cells","volume":"47","author":"Chen","year":"2009","journal-title":"Food Chem. Toxicol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1016\/j.mrgentox.2009.03.001","article-title":"Olaquindox-induced genotoxicity and oxidative DNA damage in human hepatoma G2 (HepG2) cells","volume":"676","author":"Zou","year":"2009","journal-title":"Mutat. Res. Gen. Tox. Environ. Mutagen."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1016\/0165-1218(83)90130-1","article-title":"Cytogenetic Effects Of Quinoxaline-1,4-Dioxide-Type Growth-Promoting Agents. 2. Metaphase Analysis In Mice","volume":"117","author":"Cihak","year":"1983","journal-title":"Mutat. Res. Genet. Toxicol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1016\/j.toxlet.2010.10.010","article-title":"The metabolism of olaquindox in rats, chickens and pigs","volume":"200","author":"Liu","year":"2011","journal-title":"Toxicol. Lett."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1016\/j.mrfmmm.2005.12.017","article-title":"Molecular mechanism of mutagenesis induced by olaquindox using a shuttle vector pSP189\/mammalian cell system","volume":"599","author":"Hao","year":"2006","journal-title":"Mutat. Res. Fund. Mol. Mech."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1080\/03602532.2016.1189560","article-title":"The critical role of oxidative stress in the toxicity and metabolism of quinoxaline 1,4-di-N-oxides in vitro and in vivo","volume":"48","author":"Wang","year":"2016","journal-title":"Drug Metab. Rev."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"229","DOI":"10.1007\/s10565-013-9249-y","article-title":"Olaquindox-induced apoptosis is suppressed through p38 MAPK and ROS-mediated JNK pathways in HepG2 cells","volume":"29","author":"Zhao","year":"2013","journal-title":"Cell Biol. Toxicol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1016\/j.etap.2016.07.012","article-title":"Effect of GADD45a on olaquindox-induced apoptosis in human hepatoma G2 cells: Involvement of mitochondrial dysfunction","volume":"46","author":"Li","year":"2016","journal-title":"Environ. Toxicol. Pharmacol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"709","DOI":"10.1002\/jat.3022","article-title":"Reactive oxygen species-dependent JNK downregulated olaquindox-induced autophagy in HepG2 cells","volume":"35","author":"Zhao","year":"2015","journal-title":"J. Appl. Toxicol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2247","DOI":"10.1080\/15548627.2015.1112484","article-title":"GADD45A inhibits autophagy by regulating the interaction between BECN1 and PIK3C3","volume":"11","author":"Zhang","year":"2015","journal-title":"Autophagy"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"e2445","DOI":"10.1038\/cddis.2016.322","article-title":"Inhibition of autophagy increased AGE\/ROS-mediated apoptosis in mesangial cells","volume":"7","author":"Xu","year":"2016","journal-title":"Cell Death Dis."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"37909","DOI":"10.1074\/jbc.M109.093724","article-title":"TGF-beta 1 Protects against Mesangial Cell Apoptosis via Induction of Autophagy","volume":"285","author":"Ding","year":"2010","journal-title":"J. Biol. Chem."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1242\/jcs.064576","article-title":"The regulation of autophagy-unanswered questions","volume":"124","author":"Chen","year":"2011","journal-title":"J. Cell Sci."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"654","DOI":"10.3109\/15376516.2014.956915","article-title":"Inhibition of autophagy promotes caspase-mediated apoptosis by tunicamycin in HepG2 cells","volume":"24","author":"Zhang","year":"2014","journal-title":"Toxicol. Mech. Methods"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"4685","DOI":"10.1007\/s12035-015-9396-7","article-title":"Colistin-Induced Apoptosis of Neuroblastoma-2a Cells Involves the Generation of Reactive Oxygen Species, Mitochondrial Dysfunction, and Autophagy","volume":"53","author":"Dai","year":"2016","journal-title":"Mol. Neurobiol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"301","DOI":"10.3109\/15376516.2016.1172690","article-title":"AKT\/TSC2\/p70S6K signaling pathway is involved in quinocetone-induced death-promoting autophagy in HepG2 cells","volume":"26","author":"Zhang","year":"2016","journal-title":"Toxicol. Mech. Methods"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1284","DOI":"10.1183\/09031936.00099606","article-title":"Lymphangioleiomyomatosis","volume":"28","author":"Zarogiannis","year":"2006","journal-title":"Eur. Respir. J."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Taneike, M., Nishida, K., Omiya, S., Zarrinpashneh, E., Misaka, T., Kitazume-Taneike, R., Austin, R., Takaoka, M., Yamaguchi, O., and Gambello, M.J. (2016). mTOR Hyperactivation by Ablation of Tuberous Sclerosis Complex 2 in the Mouse Heart Induces Cardiac Dysfunction with the Increased Number of Small Mitochondria Mediated through the Down-Regulation of Autophagy. PLoS ONE, 11.","DOI":"10.1371\/journal.pone.0152628"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"3865","DOI":"10.1093\/hmg\/ddu101","article-title":"Neuronal Tsc1\/2 complex controls autophagy through AMPK-dependent regulation of ULK1","volume":"23","author":"Wertz","year":"2014","journal-title":"Hum. Mol. Genet."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"470","DOI":"10.1021\/tx5004326","article-title":"Deoxidation Rates Play a Critical Role in DNA Damage Mediated by Important Synthetic Drugs, Quinoxaline 1,4-Dioxides","volume":"28","author":"Wang","year":"2015","journal-title":"Chem. Res. Toxicol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1016\/j.yrtph.2013.04.005","article-title":"Nrf2\/ARE is the potential pathway to protect Sprague-Dawley rats against oxidative stress induced by quinocetone","volume":"66","author":"Yu","year":"2013","journal-title":"Regul. Toxicol. Pharm."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"792","DOI":"10.1016\/j.etap.2015.09.008","article-title":"Olaquindox induces DNA damage via the lysosomal and mitochondrial pathway involving ROS production and p53 activation in HEK293 cells","volume":"40","author":"Yang","year":"2015","journal-title":"Environ. Toxicol. Pharmacol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"579","DOI":"10.1128\/AAC.03925-14","article-title":"Lycopene Attenuates Colistin-Induced Nephrotoxicity in Mice via Activation of the Nrf2\/HO-1 Pathway","volume":"59","author":"Dai","year":"2015","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"688","DOI":"10.1038\/ncb1426","article-title":"Autophagic and tumour suppressor activity of a novel Beclin1-binding protein UVRAG","volume":"8","author":"Liang","year":"2006","journal-title":"Nat. Cell Biol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"15077","DOI":"10.1073\/pnas.2436255100","article-title":"Beclin 1, an autophagy gene essential for early embryonic development, is a haploinsufficient tumor suppressor","volume":"100","author":"Yue","year":"2003","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.lfs.2015.03.001","article-title":"The S6K protein family in health and disease","volume":"131","author":"Tavares","year":"2015","journal-title":"Life Sci."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"232","DOI":"10.1042\/BST0370232","article-title":"Nutrient-dependent regulation of autophagy through the target of rapamycin pathway","volume":"37","author":"Chang","year":"2009","journal-title":"Biochem. Soc. Trans."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"838","DOI":"10.4161\/auto.6.7.12113","article-title":"ROS-mediated mechanisms of autophagy stimulation and their relevance in cancer therapy","volume":"6","author":"Dewaele","year":"2010","journal-title":"Autophagy"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1016\/j.bbrc.2011.09.046","article-title":"Mitochondrial ROS generation for regulation of autophagic pathways in cancer","volume":"414","author":"Li","year":"2011","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"5059","DOI":"10.3892\/ol.2016.5367","article-title":"Wogonin induces Beclin-1\/PI3K and reactive oxygen species-mediated autophagy in human pancreatic cancer cells","volume":"12","author":"Li","year":"2016","journal-title":"Oncol. Lett."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"9591482","DOI":"10.1155\/2016\/9591482","article-title":"CLOCK Promotes Endothelial Damage by Inducing Autophagy through Reactive Oxygen Species","volume":"2016","author":"Tang","year":"2016","journal-title":"Oxid. Med. Cell Longev."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"527","DOI":"10.1111\/jnc.12643","article-title":"Tnfaip8 l1\/Oxi-beta binds to FBXW5, increasing autophagy through activation of TSC2 in a Parkinson\u2019s disease model","volume":"129","author":"Ha","year":"2014","journal-title":"J. Neurochem."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1173","DOI":"10.4161\/auto.7.10.16681","article-title":"Impaired autophagy due to constitutive mTOR activation sensitizes TSC2-null cells to cell death under stress","volume":"7","author":"Ng","year":"2011","journal-title":"Autophagy"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"13571","DOI":"10.1073\/pnas.202476899","article-title":"Tuberous sclerosis complex-1 and -2 gene products function together to inhibit mammalian target of rapamycin (mTOR)-mediated downstream signaling","volume":"99","author":"Tee","year":"2002","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Alexander, A., Cai, S.L., Kim, J., Nanez, A., Sahin, M., MacLean, K.H., Inoki, K., Guan, K.L., Shen, J.J., and Person, M.D. (2010, January 17\u201321). ATM signals to TSC2 in the cytoplasm to regulate mTORC1 and autophagy in response to ROS. Proceedings of the AACR 101st Annual Meeting, Washington, DC, USA.","DOI":"10.1158\/1538-7445.AM10-4831"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1186","DOI":"10.1038\/ncb2822","article-title":"A tuberous sclerosis complex signalling node at the peroxisome regulates mTORC1 and autophagy in response to ROS","volume":"15","author":"Zhang","year":"2013","journal-title":"Nat. Cell Biol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1016\/j.freeradbiomed.2015.06.007","article-title":"The antioxidant function of sestrins is mediated by promotion of autophagic degradation of Keap1 and Nrf2 activation and by inhibition of mTORC1","volume":"88","author":"Rhee","year":"2015","journal-title":"Free Radic. Biol. Med."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Li, Y., Li, X., Liu, J., Guo, W., Zhang, H.C., and Wang, J.C. (2017). Enhanced Rb\/E2F and TSC\/mTOR Pathways Induce Synergistic Inhibition in PDGF-Induced Proliferation in Vascular Smooth Muscle Cells. PLoS ONE, 12.","DOI":"10.1371\/journal.pone.0170036"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Dai, C.S., Li, D.W., Gong, L.J., Xiao, X.L., and Tang, S.S. (2016). Curcumin Ameliorates Furazolidone-Induced DNA Damage and Apoptosis in Human Hepatocyte L02 Cells by Inhibiting ROS Production and Mitochondrial Pathway. Molecules, 21.","DOI":"10.20944\/preprints201608.0011.v1"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1016\/j.fct.2016.06.025","article-title":"Curcumin attenuates quinocetone induced apoptosis and inflammation via the opposite modulation of Nrf2\/HO-1 and NF-kB pathway in human hepatocyte L02 cells","volume":"95","author":"Dai","year":"2016","journal-title":"Food Chem. Toxicol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.fct.2015.12.004","article-title":"P21(waf1\/ciP1) plays a critical role in furazolidone-induced apoptosis in HepG2 cells through influencing the caspase-3 activation and ROS generation","volume":"88","author":"Deng","year":"2016","journal-title":"Food Chem. Toxicol."}],"container-title":["Molecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1420-3049\/22\/4\/595\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:32:13Z","timestamp":1760207533000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1420-3049\/22\/4\/595"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,4,7]]},"references-count":42,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2017,4]]}},"alternative-id":["molecules22040595"],"URL":"https:\/\/doi.org\/10.3390\/molecules22040595","relation":{},"ISSN":["1420-3049"],"issn-type":[{"value":"1420-3049","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,4,7]]}}}