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Inhibitory effect of water-soluble mulberry leaf extract on hepatic lipid accumulation in high-fat diet-fed rats via modulation of hepatic microRNA-221/222 expression and inflammation

고지방식이 급여 쥐에서 수용성 뽕나무 잎 추출물의 간 microRNA-221/222 발현 및 염증 조절을 통한 간 지질 축적억제 효과

  • Lee, Mak-Soon (Department of Nutritional Science and Food Management, Ewha Womans University) ;
  • Kim, Cheamin (Department of Nutritional Science and Food Management, Ewha Womans University) ;
  • Ko, Hyunmi (Department of Nutritional Science and Food Management, Ewha Womans University) ;
  • Kim, Yangha (Department of Nutritional Science and Food Management, Ewha Womans University)
  • 이막순 (이화여자대학교 식품영양학과) ;
  • 김채민 (이화여자대학교 식품영양학과) ;
  • 고현미 (이화여자대학교 식품영양학과) ;
  • 김양하 (이화여자대학교 식품영양학과)
  • Received : 2022.03.02
  • Accepted : 2022.04.06
  • Published : 2022.04.30

Abstract

Purpose: This study investigated the effects of water-soluble mulberry leaf extract (ME) on hepatic lipid accumulation in high-fat diet-fed rats via the regulation of hepatic microRNA (miR)-221/222 and inflammation. Methods: Male Sprague-Dawley rats (4 weeks old) were randomly divided into 3 groups (n = 7 each) and fed with 10 kcal% low-fat diet (LF), 45 kcal% high-fat diet (HF), or HF + 0.8% ME for 14 weeks. Lipid profiles and cytokine levels of the liver and serum were measured using commercial enzymatic colorimetric and enzyme-linked immunosorbent assay, respectively. The messenger RNA (mRNA) and miR levels in liver tissue were assayed by real-time quantitative reverse-transcription polymerase chain reaction. Results: Supplementation of ME reduces body weight and improves the liver and serum lipid profiles as compared to the HF group. The mRNA levels of hepatic peroxisome proliferator-activated receptor-gamma, sterol regulatory element binding protein-1c, fatty acid synthase, and fatty acid translocase, which are genes involved in lipid metabolism, were significantly downregulated in the ME group compared to the HF group. In contrast, the mRNA level of hepatic carnitine palmitoyl transferase-1 (involved in fatty acid oxidation) was upregulated by ME supplementation. Furthermore, administration of ME significantly downregulated the mRNA levels of inflammatory mediators such as hepatic tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), monocyte chemoattractant protein-1, and inducible nitric oxide synthase. The serum levels of TNF-α, IL-6, and nitric oxide were also significantly reduced in ME group compared to the HF group. Expression of hepatic miR-221 and miR-222, which increase in the inflammatory state of the liver, were also significantly inhibited in the ME group compared to the HF group. Conclusion: These results indicate that ME has the potential to improve hepatic lipid accumulation in high-fat diet-fed rats via modulation of inflammatory mediators and hepatic miR-221/222 expressions.

본 연구에서는 ME가 고지방식이를 섭취한 쥐에서 간의 miRs와 염증 조절을 통해 간 지질 축적 억제에 영향을 미치는지 조사하였다. 4주령 수컷 Sprague-Dawley 쥐는 3 그룹 (n = 7)으로 나누어 14주 동안 10 kcal% 저지방 식이 (LF), 45 kcal% 고지방 식이 (HF) 또는 HF + 0.8% ME를 공급하였다. ME의 공급은 체중 증가를 줄이고 혈청 지질 수준을 개선하였으며 간 지질 축적을 억제하였다. 간의 지방 대사에 관여하는 유전자인 PPAR-γ, SREBP-1c, FAS 및 FAT/CD36의 mRNA 수준은 HF 군에 비해 ME 군에서 유의하게 하향 조절되었다. 반면, 지방산 산화에 관여하는 CPT-1의 mRNA 수준은 HF 군에 비해 ME 군에서 유의하게 상향 조절되었다. ME는 간의 염증 매개에 관여하는 TNF-α, IL-6, MCP-1 및 iNOS의 mRNA 수준을 하향 조절하였으며 혈청의 TNF-α, IL-6 및 NO 농도 또한 유의하게 낮추었다. 비알콜성 지방간의 염증상태에서 증가하는 miR-221과 miR-222의 발현은 HF 군에 비해 ME 군에서 유의하게 억제되었다. 본 연구의 결과들은 ME의 간 지질 축적 억제 효과가 지질대사와 염증 조절에 관여하는 조절 인자의 개선 및 간의 miR-221/222 발현 억제와 관련 있음을 시사한다. 따라서, ME는 NAFLD을 개선하는 천연물 소재로서 활용될 수 있을 것으로 사료된다.

Keywords

Acknowledgement

This study was supported by the National Research Foundation of Korea (NRF) funded by the Korean Government (MSIT) (No. 2019R1A2C1002861).

References

  1. Targher G, Bertolini L, Padovani R, Rodella S, Tessari R, Zenari L, et al. Prevalence of nonalcoholic fatty liver disease and its association with cardiovascular disease among type 2 diabetic patients. Diabetes Care 2007; 30(5): 1212-1218. https://doi.org/10.2337/dc06-2247
  2. Leite NC, Salles GF, Araujo AL, Villela-Nogueira CA, Cardoso CR. Prevalence and associated factors of non-alcoholic fatty liver disease in patients with type-2 diabetes mellitus. Liver Int 2009; 29(1): 113-119. https://doi.org/10.1111/j.1478-3231.2008.01718.x
  3. Perumpail BJ, Khan MA, Yoo ER, Cholankeril G, Kim D, Ahmed A. Clinical epidemiology and disease burden of nonalcoholic fatty liver disease. World J Gastroenterol 2017; 23(47): 8263-8276. https://doi.org/10.3748/wjg.v23.i47.8263
  4. Milic S, Lulic D, Stimac D. Non-alcoholic fatty liver disease and obesity: biochemical, metabolic and clinical presentations. World J Gastroenterol 2014; 20(28): 9330-9337. https://doi.org/10.3748/wjg.v20.i28.9330
  5. Wang Y, Nakajima T, Gonzalez FJ, Tanaka N. PPARs as metabolic regulators in the liver: lessons from liver-specific PPAR-null mice. Int J Mol Sci 2020; 21(6): 2061. https://doi.org/10.3390/ijms21062061
  6. Ruiz R, Jideonwo V, Ahn M, Surendran S, Tagliabracci VS, Hou Y, et al. Sterol regulatory element-binding protein-1 (SREBP-1) is required to regulate glycogen synthesis and gluconeogenic gene expression in mouse liver. J Biol Chem 2014; 289(9): 5510-5517. https://doi.org/10.1074/jbc.M113.541110
  7. Noushmehr H, D'Amico E, Farilla L, Hui H, Wawrowsky KA, Mlynarski W, et al. Fatty acid translocase (FAT/CD36) is localized on insulin-containing granules in human pancreatic β-cells and mediates fatty acid effects on insulin secretion. Diabetes 2005; 54(2): 472-481. https://doi.org/10.2337/diabetes.54.2.472
  8. Schreurs M, Kuipers F, van der Leij FR. Regulatory enzymes of mitochondrial beta-oxidation as targets for treatment of the metabolic syndrome. Obes Rev 2010; 11(5): 380-388. https://doi.org/10.1111/j.1467-789X.2009.00642.x
  9. Luo Y, Lin H. Inflammation initiates a vicious cycle between obesity and nonalcoholic fatty liver disease. Immun Inflamm Dis 2021; 9(1): 59-73. https://doi.org/10.1002/iid3.391
  10. Tilg H. The role of cytokines in non-alcoholic fatty liver disease. Dig Dis 2010; 28(1): 179-185. https://doi.org/10.1159/000282083
  11. Akbari R, Behdarvand T, Afarin R, Yaghooti H, Jalali MT, Mohammadtaghvaei N. Saroglitazar improved hepatic steatosis and fibrosis by modulating inflammatory cytokines and adiponectin in an animal model of non-alcoholic steatohepatitis. BMC Pharmacol Toxicol 2021; 22(1): 53. https://doi.org/10.1186/s40360-021-00524-8
  12. Lechner M, Lirk P, Rieder J. Inducible nitric oxide synthase (iNOS) in tumor biology: the two sides of the same coin. Semin Cancer Biol 2005; 15(4): 277-289. https://doi.org/10.1016/j.semcancer.2005.04.004
  13. Iwakiri Y. Nitric oxide in liver fibrosis: the role of inducible nitric oxide synthase. Clin Mol Hepatol 2015; 21(4): 319-325. https://doi.org/10.3350/cmh.2015.21.4.319
  14. Pineau P, Volinia S, McJunkin K, Marchio A, Battiston C, Terris B, et al. miR-221 overexpression contributes to liver tumorigenesis. Proc Natl Acad Sci U S A 2010; 107(1): 264-269. https://doi.org/10.1073/pnas.0907904107
  15. Ogawa T, Enomoto M, Fujii H, Sekiya Y, Yoshizato K, Ikeda K, et al. MicroRNA-221/222 upregulation indicates the activation of stellate cells and the progression of liver fibrosis. Gut 2012; 61(11): 1600-1609. https://doi.org/10.1136/gutjnl-2011-300717
  16. Jiang X, Jiang L, Shan A, Su Y, Cheng Y, Song D, et al. Targeting hepatic miR-221/222 for therapeutic intervention of nonalcoholic steatohepatitis in mice. EBioMedicine 2018; 37: 307-321. https://doi.org/10.1016/j.ebiom.2018.09.051
  17. Singh R, Bagachi A, Semwal A, Kakar S, Bharadwaj A. Traditional uses, phytochemistry and pharmacology of Morus alba linn.: a review. J Med Plants Res 2013; 7(9): 461-469.
  18. Sanchez-Salcedo EM, Mena P, Garcia-Viguera C, Hernandez F, Martinez JJ. (Poly) phenolic compounds and antioxidant activity of white (Morus alba) and black (Morus nigra) mulberry leaves: their potential for new products rich in phytochemicals. J Funct Foods 2015; 18: 1039-1046. https://doi.org/10.1016/j.jff.2015.03.053
  19. Gryn-Rynko A, Bazylak G, Olszewska-Slonina D. New potential phytotherapeutics obtained from white mulberry (Morus alba L.) leaves. Biomed Pharmacother 2016; 84: 628-636. https://doi.org/10.1016/j.biopha.2016.09.081
  20. Lee E, Lee MS, Chang E, Kim CT, Choi AJ, Kim IH, et al. High hydrostatic pressure extract of mulberry leaves ameliorates hypercholesterolemia via modulating hepatic microRNA-33 expression and AMPK activity in high cholesterol diet fed rats. Food Nutr Res 2021; 65.
  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. https://doi.org/10.1093/clinchem/18.6.499
  22. Bligh EG, Dyer WJ. A rapid method of total lipid extraction and purification. Can J Biochem Physiol 1959; 37(8): 911-917. https://doi.org/10.1139/o59-099
  23. Livak KJ, Schmittgen TD. Analysis of relative gene expression data using real-time quantitative PCR and the 2-ΔΔC(T) method. Methods 2001; 25(4): 402-408. https://doi.org/10.1006/meth.2001.1262
  24. Lee MS, Kim Y. Mulberry fruit extract ameliorates adipogenesis via increasing AMPK activity and downregulating microRNA-21/143 in 3T3-L1 adipocytes. J Med Food 2020; 23(3): 266-272. https://doi.org/10.1089/jmf.2019.4654
  25. Oh KS, Ryu SY, Lee S, Seo HW, Oh BK, Kim YS, et al. Melanin-concentrating hormone-1 receptor antagonism and anti-obesity effects of ethanolic extract from Morus alba leaves in diet-induced obese mice. J Ethnopharmacol 2009; 122(2): 216-220. https://doi.org/10.1016/j.jep.2009.01.020
  26. Li R, Xue Z, Jia Y, Wang Y, Li S, Zhou J, et al. Polysaccharides from mulberry (Morus alba L.) leaf prevents obesity by inhibiting pancreatic lipase in high-fat diet induced mice. Int J Biol Macromol 2021; 192: 452-460. https://doi.org/10.1016/j.ijbiomac.2021.10.010
  27. Lim HH, Lee SO, Kim SY, Yang SJ, Lim Y. Anti-inflammatory and antiobesity effects of mulberry leaf and fruit extract on high fat diet-induced obesity. Exp Biol Med (Maywood) 2013; 238(10): 1160-1169. https://doi.org/10.1177/1535370213498982
  28. Yang SJ, Park NY, Lim Y. Anti-adipogenic effect of mulberry leaf ethanol extract in 3T3-L1 adipocytes. Nutr Res Pract 2014; 8(6): 613-617. https://doi.org/10.4162/nrp.2014.8.6.613
  29. Du Y, Li DX, Lu DY, Zhang R, Zhong QQ, Zhao YL, et al. Amelioration of lipid accumulations and metabolism disorders in differentiation and development of 3T3-L1 adipocytes through mulberry leaf water extract. Phytomedicine 2022; 98: 153959. https://doi.org/10.1016/j.phymed.2022.153959
  30. Lee YJ, Tsai MC, Lin HT, Wang CJ, Kao SH. Aqueous mulberry leaf extract ameliorates alcoholic liver injury associating with upregulation of ethanol metabolism and suppression of hepatic lipogenesis. Evid Based Complement Alternat Med 2021; 2021: 6658422.
  31. Huang P, Hao M, Gao Q, Ruan J, Yang S, Liu M, et al. Constituents of Morus alba var. multicaulis leaf improve lipid metabolism by activating the AMPK signaling pathway in HepG2 cells. J Nat Med 2022; 76(1): 200-209. https://doi.org/10.1007/s11418-021-01581-3
  32. Liu CG, Ma YP, Zhang XJ. Effects of mulberry leaf polysaccharide on oxidative stress in pancreatic β-cells of type 2 diabetic rats. Eur Rev Med Pharmacol Sci 2017; 21(10): 2482-2488.
  33. Anavi S, Eisenberg-Bord M, Hahn-Obercyger M, Genin O, Pines M, Tirosh O. The role of iNOS in cholesterol-induced liver fibrosis. Lab Invest 2015; 95(8): 914-924. https://doi.org/10.1038/labinvest.2015.67
  34. Liang HW, Yang TY, Teng CS, Lee YJ, Yu MH, Lee HJ, et al. Mulberry leaves extract ameliorates alcoholinduced liver damages through reduction of acetaldehyde toxicity and inhibition of apoptosis caused by oxidative stress signals. Int J Med Sci 2021; 18(1): 53-64. https://doi.org/10.7150/ijms.50174
  35. Lee MR, Kim JE, Park JW, Kang MJ, Choi HJ, Bae SJ, et al. Fermented mulberry (Morus alba) leaves suppress high fat diet-induced hepatic steatosis through amelioration of the inflammatory response and autophagy pathway. BMC Complement Med Ther 2020; 20(1): 283. https://doi.org/10.1186/s12906-020-03076-2
  36. Sugimoto M, Arai H, Tamura Y, Murayama T, Khaengkhan P, Nishio T, et al. Mulberry leaf ameliorates the expression profile of adipocytokines by inhibiting oxidative stress in white adipose tissue in db/db mice. Atherosclerosis 2009; 204(2): 388-394. https://doi.org/10.1016/j.atherosclerosis.2008.10.021
  37. Lodge R, Ferreira Barbosa JA, Lombard-Vadnais F, Gilmore JC, Deshiere A, Gosselin A, et al. Host microRNAs-221 and -222 inhibit HIV-1 entry in macrophages by targeting the CD4 viral receptor. Cell Rep 2017; 21(1): 141-153. https://doi.org/10.1016/j.celrep.2017.09.030
  38. Garofalo M, Di Leva G, Romano G, Nuovo G, Suh SS, Ngankeu A, et al. miR-221&222 regulate TRAIL resistance and enhance tumorigenicity through PTEN and TIMP3 downregulation. Cancer Cell 2009; 16(6): 498-509. https://doi.org/10.1016/j.ccr.2009.10.014