Elajik Asit, Diyabetik Böbrek Hasarında TGFβ1/Smad Kaynaklı Böbrek Fibrozisini İnhibe Eder

Abstract

Amaç: Diabetes mellitus (DM) patogenezinde meydana gelen hiperglisemi nedeniyle serbest radikal oluşumu artar ve bunun sonucunda da oksidatif stres meydana gelir. Hiperglisemi aracılı oksidatif stres, diyabetik nefropatinin patogenezinde önemli bir rol oynar. Elajik asit (EA)’in antihiperglisemik, antioksidatif, antiapoptotik ve antiinflamatuar etkileri birçok çalışma ile gösterilmiştir. Bu çalışmada, streptozotosin ile indüklenen diyabetik nefropatili ratlarda EA’nın TGFβ1/Smad sinyalizasyonu üzerine antifibrotik etkisinin gösterilmesi amaçlandı. Gereç ve Yöntemler: Bu çalışmada, ağırlığı 200-250 g arasında olan toplam 24 adet erkek Sprague Dawley cinsi sıçan kullanıldı. Hayvanlar kontrol, EA, DM ve DM+EA grupları olmak üzere dört gruba ayrıldı. Böbrek dokuları histolojik ve immünohistokimyasal prosedürler için kullanıldı. Masson trikrom boyaması ile böbrek dokularındaki kollajen yoğunluğu ortaya koyulurken, fibrotik belirteçler olan TGFβ1, p-Smad3 ve αSMA'nın ekspresyon seviyeleri ise immünositokimyasal yöntem ile belirlendi. Bulgular: DM grubunun böbrek dokusundaki kollajen yoğunluğunun intertübüler alanda önemli bir ölçüde arttığı gösterilirken, EA ile tedavi edilen DM grubunda ise kollajen yoğunluğunun istatistiksel olarak anlamlı bir derecede azaldığı gösterildi. Tüm grupların böbrek doku kesitlerinde TGFβ1, p-Smad3 ve αSMA immünopozitifliği değerlendirildiğinde ise en yüksek boyanma yoğunluğu DM grubunda olurken, tedavi grubunda boyanma yoğunluğu ise kontrol grubuna yakındı. αSMA, TGFβ1 ve p-Smad3 protein ekspresyonunun EA tedavisi ile aşağı regüle edildiği gözlendi. Sonuç: Elajik asit, diyabetik nefropatide profibrotik parametreleri normal seviyelere döndürerek fibrozu azaltmıştır.

Keywords

• Diabetes mellitus
• elajik asit
• fibrozis
• böbrek
• TGFβ/Smad

Ellagic Acid Inhibits TGFβ1/Smad-Induced Renal Fibrosis in Diabetic Kidney Injury

Abstract

Aim: Free radical formation increases due to hyperglycemia occurring in the pathogenesis of diabetes mellitus (DM), and as a result, oxidative stress occurs. Hyperglycemia-mediated oxidative stress plays an important role in the pathogenesis of diabetic nephropathy. The antihyperglycemic, antioxidative, anti-apoptotic, and anti-inflammatory effects of ellagic acid (EA) have been demonstrated by many studies. In this study, it was aimed to demonstrate the antifibrotic effect of EA on TGFβ1/Smad signaling in rats with streptozotocin induced diabetic nephropathy. Material and Methods: A total of 24 male Sprague Dawley rats, weighing 200-250 g, were used in this study. The animals were divided into four groups as control, EA, DM, and DM+EA. The kidney tissues were used for histological and immunohistochemical procedures. While the collagen density in kidney tissues was revealed by Masson's trichrome staining, the expression levels of fibrotic markers TGFβ1, p-Smad3, and αSMA were determined by the immunocytochemical method. Results: It was shown that the collagen density in the renal tissue of the DM group increased significantly in the intertubular area, while the collagen density in the EA-treated DM group was statistically significantly decreased. When TGFβ1, p-Smad3, and αSMA immunopositivity in kidney tissue sections of all groups were evaluated, the highest staining intensity was in the DM group, while the intensity of staining was close to the control group in the treatment group. It was observed that αSMA, TGFβ1, and p-Smad3 protein expression were down-regulated with EA treatment. Conclusion: EA reduced fibrosis in diabetic nephropathy by returning profibrotic parameters to normal levels.

Keywords

• Diabetes mellitus
• ellagic acid
• fibrosis
• kidney
• TGFβ/Smad

References

1. Alicic RZ, Rooney MT, Tuttle KR. Diabetic kidney disease: challenges, progress, and possibilities. Clin J Am Soc Nephrol. 2017;12(12):2032-45.
2. Tuttle KR, Bakris GL, Bilous RW, Chiang JL, de Boer IH, Goldstein-Fuchs J, et al. Diabetic kidney disease: a report from an ADA Consensus Conference. Diabetes care. 2014;37(10):2864-83.
3. Thomas MC, Brownlee M, Susztak K, Sharma K, Jandeleit-Dahm KA, Zoungas S, et al. Diabetic kidney disease. Nat Rev Dis Primers. 2015;1:15018.
4. Humphreys BD. Mechanisms of renal fibrosis. Annu Rev Physiol. 2018;80:309-26.
5. Yoon JJ, Park JH, Lee YJ, Kim HY, Han BH, Jin HG, et al. Protective effects of ethanolic extract from rhizome of Polygoni avicularis against renal fibrosis and inflammation in a diabetic nephropathy model. Int J Mol Sci. 2021;22(13):7230.
6. Reeves WB, Andreoli TE. Transforming growth factor β contributes to progressive diabetic nephropathy. Proc Natl Acad Sci. 2000;97(14):7667-9.
7. Ka SM, Yeh YC, Huang XR, Chao TK, Hung YJ, Yu CP, et al. Kidney-targeting Smad7 gene transfer inhibits renal TGF-β/MAD homologue (SMAD) and nuclear factor κB (NF-κB) signalling pathways, and improves diabetic nephropathy in mice. Diabetologia. 2012;55(2):509-19.
8. Barnes JL, Glass Ii WF. Renal interstitial fibrosis: a critical evaluation of the origin of myofibroblasts. Contrib Nephrol. 2011;169:73-93.

9. Li J, Yue S, Fang J, Zeng J, Chen S, Tian J, et al. MicroRNA-10a/b inhibit TGF-β/Smad-induced renal fibrosis by targeting TGF-β receptor 1 in diabetic kidney disease. Mol Ther Nucleic Acids. 2022;28:488-99.
10. Hocevar BA, Brown TL, Howe PH. TGF-beta induces fibronectin synthesis through a c-Jun N-terminal kinase-dependent, Smad4-independent pathway. EMBO J. 1999;18(5):1345-56.
11. Hu B, Wu Z, Phan SH. Smad3 mediates transforming growth factor-β–induced α-smooth muscle actin expression. Am J Respir Cell Mol Biol. 2003;29(3 Pt 1):397-404.
12. Wang D, Zhang G, Chen X, Wei T, Liu C, Chen C, et al. Sitagliptin ameliorates diabetic nephropathy by blocking TGF-β1/Smad signaling pathway. Int J Mol Med. 2018;41(5):2784-92.
13. Wilson PG, Thompson JC, Yoder MH, Charnigo R, Tannock LR. Prevention of renal apoB retention is protective against diabetic nephropathy: role of TGF-β inhibition. J Lipid Res. 2017;58(12):2264-74.
14. Baynes JW. Role of oxidative stress in development of complications in diabetes. Diabetes. 1991;40(4):405-12.
15. Wolff SP. Diabetes mellitus and free radicals: free radicals, transition metals and oxidative stress in the aetiology of diabetes mellitus and complications. Br Med Bull. 1993;49(3):642-52.
16. González‐Sarrías A, Espín JC, Tomás‐Barberán FA, García-Conesa MT. Gene expression, cell cycle arrest and MAPK signalling regulation in Caco‐2 cells exposed to ellagic acid and its metabolites, urolithins. Mol Nutr Food Res. 2009;53(6):686-98.
17. Kuo MY, Ou HC, Lee WJ, Kuo WW, Hwang LL, Song TY, et al. Ellagic acid inhibits oxidized low-density lipoprotein (OxLDL)-induced metalloproteinase (MMP) expression by modulating the protein kinase C-α/extracellular signal-regulated kinase/peroxisome proliferator-activated receptor γ/nuclear factor-κB (PKC-α/ERK/PPAR-γ/NF-κB) signaling pathway in endothelial cells. J Agric Food Chem. 2011;59(9):5100-8.
18. Devipriya N, Srinivasan M, Sudheer AR, Menon VP. Effect of ellagic acid, a natural polyphenol, on alcohol-induced prooxidant and antioxidant imbalance: a drug dose dependent study. Singapore Med J. 2007;48(4):311-8.
19. Rogerio AP, Fontanari C, Melo MC, Ambrosio SR, de Souza GE, Pereira PS, et al. Anti-inflammatory, analgesic and anti-oedematous effects of Lafoensia pacari extract and ellagic acid. J Pharm Pharmacol. 2006;58(9):1265-73.
20. Fatima N, Hafizur RM, Hameed A, Ahmed S, Nisar M, Kabir N. Ellagic acid in Emblica officinalis exerts anti-diabetic activity through the action on β-cells of pancreas. Eur J Nut. 2017;56(2):591-601.
21. Malini P, Kanchana G, Rajadurai M. Antibiabetic efficacy of ellagic acid in streptozotocin-induced diabetes mellitus in albino wistar rats. Asian J Pharm Clin Res. 2011;4(3):124-8.
22. Akarca Dizakar SÖ, Saribas GS, Tekcan A. Effects of ellagic acid in the testes of streptozotocin induced diabetic rats. Drug Chem Toxicol. 2022;45(5):2123-30.
23. Sellamuthu PS, Arulselvan P, Muniappan BP, Fakurazi S, Kandasamy M. Mangiferin from Salacia chinensis prevents oxidative stress and protects pancreatic β-cells in streptozotocin-induced diabetic rats. J Med Food. 2013;16(8):719-27.
24. Meng S, Yang F, Wang Y, Qin Y, Xian H, Che H, et al. Silymarin ameliorates diabetic cardiomyopathy via inhibiting TGF‐β1/Smad signaling. Cell Biol Int. 2019;43(1):65-72.
25. Mari Kannan M, Darlin Quine S. Mechanistic clues in the protective effect of ellagic acid against apoptosis and decreased mitochondrial respiratory enzyme activities in myocardial infarcted rats. Cardiovasc Toxicol. 2012;12(1):56-63.
26. Wei DZ, Lin C, Huang YQ, Wu LP, Huang MY. Ellagic acid promotes ventricular remodeling after acute myocardial infarction by up-regulating miR-140-3p. Biomed Pharmacother. 2017;95:983-9.
27. Matough FA, Budin SB, Hamid ZA, Alwahaibi N, Mohamed J. The role of oxidative stress and antioxidants in diabetic complications. Sultan Qaboos Univ Med J. 2012;12(1):5-18.
28. Shu G, Dai C, Yusuf A, Sun H, Deng X. Limonin relieves TGF-β-induced hepatocyte EMT and hepatic stellate cell activation in vitro and CCl4-induced liver fibrosis in mice via upregulating Smad7 and subsequent suppression of TGF-β/Smad cascade. J Nutr Biochem. 2022;107:109039.
29. Heldin CH, Moustakas A. Role of Smads in TGFβ signaling. Cell Tissue Res. 2012;347(1):21-36.