Interrelationship between nuclear factor-erythroid-2-related factor 2, NADPH quinone oxidoreductase and lipoprotein-associated phospholipase A2 expression in young patients of metabolic syndrome

  • Seema GargEmail author
  • Mohit Mehndiratta
  • Rajarshi Kar
  • Pranav Malik
Original Article


Metabolic syndrome (MS) is associated with inflammation and oxidative stress (OS). Keap1/Nrf2/ARE is a cytoprotective pathway induced by OS and inflammation. This study aims to evaluate the expression of nuclear factor-erythroid-2-related factor 2 (Nrf2) and its downstream target gene NADPH quinone oxidoreductase-1 (NQO-1) in MS. Since lipoprotein-associated phospholipase A2(LpPLA2) is an important inflammatory marker believed to have a role in complications of MS, the association of its expression with that of Nrf2 and NQO-1 was also studied. Medical students (n = 26) were categorised in two groups according to NCEP ATP III criteria with WHO criteria for obesity for South Asian region: patients of MS (n = 13) and controls (n = 13). mRNA expression of Nrf2, NQO-1 and LpPLA2 genes was evaluated by qPCR in blood using specific primers. Fold change was calculated by 2–ΔΔcT method keeping β-actin as internal control. Expression of NQO-1 and LpPLA2 was found to be higher in MS. However, Nrf2 expression was low in patients who had hypertriglyceridemia when compared with patients with normal triglyceride levels. A significant correlation was observed in expression of LpPLA2, with Nrf2 and NQO-1. Our data suggests that there may be compensatory activation of antioxidant defence mechanism in young patients of MS. Further evidence is provided by higher expression of LpPLA2 and its correlation with Nrf2 and NQO-1 in MS which suggests that inflammatory stress may induce expression of genes of cytoprotective pathways. Additionally, this study, for the first time, indicates that Nrf2 may have some role in regulating triglyceride (TG) concentration.


Metabolic syndrome Lipoprotein-associated phospholipase A2 Nuclear factor E2-related factor 2 NAD(P)H quinone oxidoreductase 1 



The authors covey their gratitude to the patients, and to the technical staff of the department of Biochemistry and hospital laboratory services.

Authors’ contributions

Dr. Seema Garg and Dr. Mohit Mehndiratta conceptualised and designed the study. Pranav Malik and Dr. Seema Garg acquired the data with help from Dr. Rajarshi and Dr. Mohit Mehndiratta. Dr. Seema Garg statistically analysed and interpreted the data. Manuscript was drafted by Dr. Seema Garg, Dr. Rajarshi Kar and Dr. Mohit Mehndiratta. Critical review of manuscript was done by all authors.


The study was conducted under the Short Term Studentship program (reference ID: 2014—04698) of Indian Council of Medical Research, New Delhi.

Compliance with ethical standards

Conflict of interest.

The authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.



Nuclear factor-erythroid-2-related factor 2 (Nrf2)


NAD(P)H quinone oxidoreductase-1






Lipoprotein-associated phospholipase A2


Metabolic syndrome


Oxidative stress


Methionine- and choline-deficient diet


  1. 1.
    The IDF consensus worldwide definition of the metabolic syndrome. Available from: Accessed on 2017 Nov 28.
  2. 2.
    Jain SR, Shah KH, Acharya HN, Barot K, Sharma KH. Prevalence and predictors of metabolic syndrome in young asymptomatic Gujarati population. Int J Chronic Dis 2015 Available from: Accessed on 2017 Nov 28], 1, 7.
  3. 3.
    Chandey M, Kaur S, Kaur H. Prevalence of metabolic syndrome in young adults: a study from North India. Int J Adv Med. 2017;4(2):463–6.CrossRefGoogle Scholar
  4. 4.
    Marseglia L, Manti S, D’Angelo G, Nicotera A, Parisi E, Di Rosa G, et al. Oxidative stress in obesity: a critical component in human diseases. Int J Mol Sci. 2014;16(1):378–400.CrossRefGoogle Scholar
  5. 5.
    Bergman RN, Kim SP, Hsu IR, Catalano KJ, Chiu JD, Kabir M, Richey JM, Ader M Abdominal obesity: role in the pathophysiology of metabolic disease and cardiovascular risk. Am J Med 2007;120(2 Suppl 1):S3–S8; discussion S29–32. DOI
  6. 6.
    Lee J-M, Johnson JA. An important role of Nrf2-ARE pathway in the cellular defense mechanism. J Biochem Mol Biol. 2004;37(2):139–43.Google Scholar
  7. 7.
    Motohashi H, Yamamoto M. Nrf2-Keap1 defines a physiologically important stress response mechanism. Trends Mol Med. 2004;10(11):549–57.CrossRefGoogle Scholar
  8. 8.
    Lee J-M, Li J, Johnson DA, Stein TD, Kraft AD, Calkins MJ, et al. Nrf2, a multi-organ protector? FASEB J Off Publ Fed Am Soc Exp Biol. 2005;19(9):1061–6.Google Scholar
  9. 9.
    Pi J, Leung L, Xue P, Wang W, Hou Y, Liu D, et al. Deficiency in the nuclear factor E2-related factor-2 transcription factor results in impaired adipogenesis and protects against diet-induced obesity. J Biol Chem. 2010;285(12):9292–300.CrossRefGoogle Scholar
  10. 10.
    Sykiotis GP, Habeos IG, Samuelson AV, Bohmann D. The role of the antioxidant and longevity-promoting Nrf2 pathway in metabolic regulation. Curr Opin Clin Nutr Metab Care. 2011;14(1):41–8.CrossRefGoogle Scholar
  11. 11.
    Dinkova-Kostova AT, Talalay P. NAD(P)H:quinone acceptor oxidoreductase 1 (NQO1), a multifunctional antioxidant enzyme and exceptionally versatile cytoprotector. Arch Biochem Biophys. 2010;501(1):116–23.CrossRefGoogle Scholar
  12. 12.
    Hwang JH, Kim DW, Jo EJ, Kim YK, Jo YS, Park JH, et al. Pharmacological stimulation of NADH oxidation ameliorates obesity and related phenotypes in mice. Diabetes. 2009;58(4):965–74.CrossRefGoogle Scholar
  13. 13.
    Madjid M, Ali M, Willerson JT. Lipoprotein-associated phospholipase A2 as a novel risk marker for cardiovascular disease: a systematic review of the literature. Tex Heart Inst J. 2010;37(1):25–39.Google Scholar
  14. 14.
    Tselepis AD, John Chapman M. Inflammation, bioactive lipids and atherosclerosis: potential roles of a lipoprotein-associated phospholipase A2, platelet activating factor-acetylhydrolase. Atheroscler Suppl. 2002;3(4):57–68.CrossRefGoogle Scholar
  15. 15.
    Gong H, Du Y, Zhong L, Dong Z, Wang X, Mao Y, et al. Plasma lipoprotein-associated phospholipase A2 in patients with metabolic syndrome and carotid atherosclerosis. Lipids Health Dis. 2011;10:13.CrossRefGoogle Scholar
  16. 16.
    Persson M, Hedblad B, Nelson JJ, Berglund G. Elevated Lp-PLA2 levels add prognostic information to the metabolic syndrome on incidence of cardiovascular events among middle-aged nondiabetic subjects. Arterioscler Thromb Vasc Biol. 2007;27(6):1411–6.CrossRefGoogle Scholar
  17. 17.
    Garg S, Malik P, Kar R, Sankar V, Mehndiratta M. Expression of lipoprotein associated phospholipase A2 enzyme in medical undergraduate students with metabolic syndrome. Diabetes Metab Syndr. 2016;10(1 Suppl 1):S21–4.CrossRefGoogle Scholar
  18. 18.
    Expert Panel on detection, evaluation, and treatment of high blood cholesterol in adults. Executive summary of the third report of the National Cholesterol Education Program (NCEP) expert panel on detection, evaluation, and treatment of high blood cholesterol in adults (adult treatment panel III). JAMA. 2001;285(19):2486–97.CrossRefGoogle Scholar
  19. 19.
    World Health Organization. The Asia-Pacific perspective: redefining obesity and its treatment. In: WHO: Geneva; 2000.Google Scholar
  20. 20.
    WHO | STEPS Manual. WHO. Available from: Accessed on 2017 Nov 28.
  21. 21.
    Friedewald WT, Levy RI, Fredrickson DS. Estimation of the concentration of low-density lipoprotein cholesterol in plasma, without use of the preparative ultracentrifuge. Clin Chem. 1972;18(6):499–502.Google Scholar
  22. 22.
    Riedmaier I, Pfaffl MW. Transcriptional biomarkers—high throughput screening, quantitative verification, and bioinformatical validation methods. Methods San Diego Calif. 2013;59(1):3–9.CrossRefGoogle Scholar
  23. 23.
    Suzuki T, Yamamoto M. Molecular basis of the Keap1-Nrf2 system. Free Radic Biol Med. 2015;88(Pt B):93–100.CrossRefGoogle Scholar
  24. 24.
    Mutter FE, Park BK, Copple IM. Value of monitoring Nrf2 activity for the detection of chemical and oxidative stress. Biochem Soc Trans. 2015;43(4):657–62.CrossRefGoogle Scholar
  25. 25.
    Das SK, Sharma NK, Hasstedt SJ, Mondal AK, Ma L, Langberg KA, et al. An integrative genomics approach identifies activation of Thioredoxin/Thioredoxin reductase-1-mediated oxidative stress defense pathway and inhibition of angiogenesis in obese nondiabetic human subjects. J Clin Endocrinol Metab. 2011;96(8):E1308–13.CrossRefGoogle Scholar
  26. 26.
    Santillán LD, Moyano M, Frau M, Flores O, Siewert S, Zirulnick F, et al. Reduced blood nrf-2 mRNA in local overweight boys at risk of metabolic complications: a study in San Luis City, San Luis, Argentina. Metab Syndr Relat Disord. 2013;11(5):359–65.CrossRefGoogle Scholar
  27. 27.
    Yates MS, Tran QT, Dolan PM, Osburn WO, Shin S, McCulloch CC, et al. Genetic versus chemoprotective activation of Nrf2 signaling: overlapping yet distinct gene expression profiles between Keap1 knockout and triterpenoid-treated mice. Carcinogenesis. 2009;30(6):1024–31.CrossRefGoogle Scholar
  28. 28.
    Kitteringham NR, Abdullah A, Walsh J, Randle L, Jenkins RE, Sison R, et al. Proteomic analysis of Nrf2 deficient transgenic mice reveals cellular defence and lipid metabolism as primary Nrf2-dependent pathways in the liver. J Proteome 201016;73(8):1612–1631, 2010.Google Scholar
  29. 29.
    Sugimoto H, Okada K, Shoda J, Warabi E, Ishige K, Ueda T, et al. Deletion of nuclear factor-E2-related factor-2 leads to rapid onset and progression of nutritional steatohepatitis in mice. Am J Physiol Gastrointest Liver Physiol. 2010;298(2):G283–94.CrossRefGoogle Scholar
  30. 30.
    Zhang Y-KJ, Yeager RL, Tanaka Y, Klaassen CD. Enhanced expression of Nrf2 in mice attenuates the fatty liver produced by a methionine- and choline-deficient diet. Toxicol Appl Pharmacol. 2010;245(3):326–34.CrossRefGoogle Scholar
  31. 31.
    Li W, Khor TO, Xu C, Shen G, Jeong W-S, Yu S, et al. Activation of Nrf2-antioxidant signaling attenuates NF-κB-inflammatory response and elicits apoptosis. Biochem Pharmacol. 2008;76(11):1485–9.CrossRefGoogle Scholar
  32. 32.
    Wang W-Y, Li J, Yang D, Xu W, Zha R, Wang Y. OxLDL stimulates lipoprotein-associated phospholipase A2 expression in THP-1 monocytes via PI3K and p38 MAPK pathways. Cardiovasc Res. 2010;85(4):845–52.CrossRefGoogle Scholar
  33. 33.
    Chartoumpekis DV, Kensler TW. New player on an old field: the Keap1/Nrf2 pathway as a target for treatment of type 2 diabetes and metabolic syndrome. Curr Diabetes Rev. 2013;9(2):137–45.Google Scholar
  34. 34.
    Hatoum IJ, Nelson JJ, Cook NR, Hu FB, Rimm EB. Dietary, lifestyle, and clinical predictors of lipoprotein-associated phospholipase A2 activity in individuals without coronary artery disease. Am J Clin Nutr. 2010;91(3):786–93.CrossRefGoogle Scholar

Copyright information

© Research Society for Study of Diabetes in India 2018

Authors and Affiliations

  • Seema Garg
    • 1
    Email author
  • Mohit Mehndiratta
    • 1
  • Rajarshi Kar
    • 1
  • Pranav Malik
    • 2
  1. 1.Department of BiochemistryUniversity College of Medical Sciences & GTB Hospital (University of Delhi)DelhiIndia
  2. 2.University College of Medical Sciences and GTB Hospital, University of DelhiDelhiIndia

Personalised recommendations