The Protective Effects of Citral, Silymarin, and Thymoquinone on Methotrexate-Induced Nephrotoxicity: A Comparative Study
Abstract
Objectives: Methotrexate (MTX) is an effective chemotherapeutic and immunosuppressive agent; however, its clinical use is limited due to nephrotoxicity associated with oxidative stress. This study aims to evaluate the protective effects of silymarin, citral, and thymoquinone against MTX-induced renal injury in rats.
Methods: Forty-eight adult male Sprague–Dawley rats were randomly assigned into six groups (n=8): healthy control, cosolvent control (DMSO), MTX-only, MTX+citral (30 mg/kg), MTX+silymarin (50 mg/kg), and MTX+thymoquinone (10 mg/kg). Treatments were administered intraperitoneally for 10 consecutive days. Methotrexate (20 mg/kg, i.p.) was administered to all groups except the healthy control. Serum urea and creatinine levels were measured, while renal tissues were evaluated for total antioxidant capacity (TAC), malondialdehyde (MDA), and histopathological alterations.
Results: MTX administration significantly increased serum urea, creatinine, and renal MDA levels while decreasing TAC compared with the healthy control group. Silymarin significantly reduced serum urea and creatinine levels and restored TAC compared with the MTX group (p<0.05). Thymoquinone significantly improved TAC and reduced MDA levels (p<0.05), although its effects on serum renal biomarkers were not statistically significant. Citral significantly decreased MDA levels (p<0.01) but showed limited effects on TAC and renal function markers. Histopathological examination demonstrated vascular and glomerular congestion with hemorrhage in the MTX group, whereas treatment groups exhibited varying degrees of structural preservation, with silymarin showing the greatest improvement.
Conclusions: Oxidative stress plays a major role in MTX-induced nephrotoxicity. Among the tested compounds, silymarin demonstrated the most consistent nephroprotective effects, while thymoquinone and citral provided partial antioxidant and histological protection. These findings support the potential use of natural antioxidants as adjunctive strategies against MTX-induced renal injury.
2. El-Agawy MSE, Badawy AMM, Rabei MR, Elshaer MMA, El Nashar EM, Alghamdi MA, et al. Methotrexate-Induced Alteration of Renal Aquaporins 1 and 2, Oxidative Stress and Tubular Apoptosis Can Be Attenuated by Omega-3 Fatty Acids Supplementation. Int J Mol Sci. 2022;23(21). https://doi.org/10.3390/ijms232112794.
3. Abdel-Wahab WM, Daifalla NS, Essawy AE. L-methionine protects against nephrotoxicity induced by methotrexate through modulation of redox status and inflammation. Redox Rep. 2023;28(1):2270886. https://doi.org/10.1080/13510002.2023.2270886.
4. Heidari R, Ahmadi A, Mohammadi H, Ommati MM, Azarpira N, Niknahad H. Mitochondrial dysfunction and oxidative stress are involved in the mechanism of methotrexate-induced renal injury and electrolytes imbalance. Biomed Pharmacother. 2018;107:834-40. https://doi.org/10.1016/j.biopha.2018.08.050.
5. Almalki RS, Eweis H, Kamal F, Kutbi D. Methotrexate toxicity: Molecular mechanisms and management. J Pharm Res Int. 2021;33(49B):204-17. https://doi.org/10.9734/jpri/2021/v33i49B33357.
6. El-Sheikh AA, Morsy MA, Abdalla AM, Hamouda AH, Alhaider IA. Mechanisms of thymoquinone hepatorenal protection in methotrexate‐induced toxicity in rats. Mediators Inflamm. 2015;2015(1):859383. https://doi.org/10.1155/2015/859383.
7. Abd El-Twab SM, Hussein OE, Hozayen WG, Bin-Jumah M, Mahmoud AM. Chicoric acid prevents methotrexate-induced kidney injury by suppressing NF-κB/NLRP3 inflammasome activation and up-regulating Nrf2/ARE/HO-1 signaling. Inflamm Res. 2019;68(6):511-23. https://doi.org/10.1007/s00011-019-01241-z.
8. Jalili C, Ghanbari A, Roshankhah S, Salahshoor MR. Toxic effects of methotrexate on rat kidney recovered by crocin as a consequence of antioxidant activity and lipid peroxidation prevention. Iran Biomed J. 2019;24(1):39. https://doi.org/10.29252/ibj.24.1.39.
9. Khoshnoud S, Mohseni Kouchesfahani H, Nabiuni M. Evaluation of The Protective Effect of Hydro-Alcoholic Extract of Raspberry Fruit on Aquaporin1 Expression in Rats Kidney Treated by Methotrexate. Cell Journal (Yakhteh). 2017;19(2):306-13. https://doi.org/10.22074/cellj.2016.3957.
10. Sakineh A, Noorbakhsh MF, Ahmadi N, Saeed N, Behdokht B. Evaluation of the Protective Effect of Citral, Silymarin, and Thymoquinone on Methotrexate-Induced Lung Injury in Rats. J Pharmacopuncture. 2023;26(2):184. https://doi.org/10.3831/KPI.2023.26.2.184.
11. Nagata T, Satou T, Hayashi S, Satyal P, Watanabe M, Riggs B, Saida Y. Citral in lemon myrtle, lemongrass, litsea, and melissa essential oils suppress the growth and invasion of breast cancer cells. BMC Complement Med Ther. 2024;24(1):211. https://doi.org/10.1186/s12906-024-04511-4.
12. Habib S, Gupta P, Bhat SS, Gupta J. In silico, in-vitro and in vivo screening of biological activities of citral. Int J Vitam Nutr Res. 2020. https://doi.org/10.1024/0300-9831/a000625.
13. Agwunobi DO, Pei T, Yang J, Wang X, Lv L, Shen R, et al. Expression profiles of glutathione S-transferases genes in semi-engorged Haemaphysalis longicornis (Acari: Ixodidae) exposed to Cymbopogon citratus essential oil. Syst Appl Acarol. 2020;25(5):918-30. https://doi.org/10.11158/saa.25.5.12.
14. Faraji M, Noorbakhsh MF, Kazemipour N, Nazifi S, Moradi HR, Ahmadi N, Azadmanesh M. Comparison of the effects of metformin, citral, Cymbopogon citratus extract and silver nanoparticles of Cymbopogon citratus extract on oxidative stress indices and Nrf2 levels in experimental type 2 diabetes in rats. Anim Models Exp Med. 2025;8(12):2128-38. https://doi.org/10.1002/ame2.70017.
15. Khatinasab S, Kazemipour N, Noorbakhsh MF, Nazifi S, Faraji M, Ahmadi N. Evaluation of Citral and Green Silver Nanoparticles From Cymbopogon citratus Extract on Biochemical Profile and Nrf2 Gene Expression in Liver Tissue of Type 2 Diabetic Rats. Biomed Res Int. 2025;2025(1):9266092. https://doi.org/10.1155/bmri/9266092.
16. Mahgoub YA, Shawky E, Ghareeb DA, Darwish FA, El Sebakhy NA, El-Hawiet AM. UPLC-MS/MS multivariate data analysis reveals phenological growth stages affect silymarin bioactive components of the different organs of two Silybum marianum genotypes. Microchem J. 2023;187:108436. https://doi.org/10.1016/j.microc.2023.108436.
17. Chahkandi S, Dabiri R, Mirmohammadkhani M, Amiri-Dashatan N, Koushki M. The effect of silymarin on liver enzymes and serum lipid profiles in Iranian patients with non-alcoholic fatty liver disease: A double-blind randomized controlled trial. Acta Biochim Iran. 2023. https://doi.org/10.18502/abi.v1i2.14105
18. Abenavoli L, Izzo AA, Milić N, Cicala C, Santini A, Capasso R. Milk thistle (Silybum marianum): A concise overview on its chemistry, pharmacological, and nutraceutical uses in liver diseases. Phytother Res. 2018;32(11):2202-13. https://doi.org/10.1002/ptr.6171.
19. Güzel S, Şahinoğullari ZU, Canacankatan N, Antmen ŞE, Kibar D, Bayrak G. The ameliorating effect of silymarin against vancomycin-induced apoptosis and inflammation in rat liver. J Res Pharm. 2019;23(4):719-28. https://doi.org/10.12991/JRP.2019.181.
20. Ivanov V, Slavova V, Georgieva D, Petrova-Tacheva V, Tolekova A. Use of silymarin for reducing nephrotoxicity caused by medicaments. Bulg Chem Commun. 2020:136-41.
21. Tiwari G, Gupta M, Devhare LD, Tiwari R. Therapeutic and phytochemical properties of thymoquinone derived from Nigella sativa. Curr Drug Res Rev. 2024;16(2):145-56. https://doi.org/10.2174/2589977515666230811092410.
22. Hosseini A, Mehri S, Aminifard T, Ghasemzadeh Rahbardar M, Nouripor S, Khajavi Rad A, et al. Renoprotective effect of thymoquinone against rhabdomyolysis-induced acute kidney injury in the rat model. Iran J Basic Med Sci. 2024;27(5):552-9. https://doi.org/10.22038/ijbms.2023.72797.15838.
23. Arjumand S, Shahzad M, Shabbir A, Yousaf MZ. Thymoquinone attenuates rheumatoid arthritis by downregulating TLR2, TLR4, TNF-α, IL-1, and NFκB expression levels. Biomed Pharmacother. 2019;111:958-63. https://doi.org/10.1016/j.biopha.2019.01.006.
24. Krishnan S, Mahadevan A, Mungle T, Gogoi MP, Saha V. Maintenance treatment in acute lymphoblastic leukemia: a clinical primer. Indian J Pediatr. 2024;91(1):47-58. https://doi.org/10.1007/s12098-023-04687-6.
25. Cronstein BN, Aune TM. Methotrexate and its mechanisms of action in inflammatory arthritis. Nat Rev Rheumatol. 2020;16(3):145-54. https://doi.org/10.1038/s41584-020-0373-9.
26. Smita P, Narayan PA, Gaurav P. Therapeutic drug monitoring for cytotoxic anticancer drugs: Principles and evidence-based practices. Front Oncol. 2022;12:1015200. https://doi.org/10.3389/fonc.2022.1015200.
27. Yang Y-y, Gao L, Ding N, Wang X-b, Zhang L-p, Gao L-h, Wang Z. How to rescue high-dose methotrexate induced nephrotoxicity and literature review about hemodiafiltration? Pak J Pharm Sci. 2020;33(3). https://doi.org/10.36721/PJPS.2020.33.3.REG.1163-1167.1.
28. Lyrio R, Rocha BRA, Corrêa ALRM, Mascarenhas MGS, Santos FL, Maia R, et al. Chemotherapy-induced acute kidney injury: epidemiology, pathophysiology, and therapeutic approaches. Front Nephrol. 2024;4:1436896-. https://doi.org/10.3389/fneph.2024.1436896.
29. Roghani M, Kalantari H, Khodayar MJ, Khorsandi L, Kalantar M, Goudarzi M, Kalantar H. Alleviation of liver dysfunction, oxidative stress and inflammation underlies the protective effect of ferulic acid in methotrexate-induced hepatotoxicity. Drug Des Devel Ther. 2020:1933-41. https://doi.org/10.2147/DDDT.S237107.
30. Aldossary SA, Chohan MS, Rasool ST. Capsaicin ameliorate the nephrotoxicity induced by methotrexate. Pak J Pharm Sci. 2021;34(6). https://doi.org/10.36721/PJPS.2021.34.6.REG.2191-2195.1
31. Kandemir FM, Kucukler S, Caglayan C, Gur C, Batil AA, Gülçin İ. Therapeutic effects of silymarin and naringin on methotrexate‐induced nephrotoxicity in rats: Biochemical evaluation of anti‐inflammatory, antiapoptotic, and antiautophagic properties. J Food Biochem. 2017;41(5):e12398. https://doi.org/10.1111/jfbc.12398.
32. Abd Eldaim MA, Barakat ER, Alkafafy M, Elaziz SAA. Antioxidant and anti-apoptotic prophylactic effect of silymarin against lead-induced hepatorenal toxicity in rats. Environ Sci Pollut Res Int. 2021;28(41):57997-8006. https://doi.org/10.1007/s11356-021-14722-8.
33. Jia C, Zhang Z, Wang J, Nie Z. Silymarin protects the rats against paraquat-induced acute kidney injury via Nrf2. Hum Exp Toxicol. 2022;41:09603271221074334. https://doi.org/10.1177/09603271221074334.
34. Abdel-Daim MM, Khalifa HA, Abushouk AI, Dkhil MA, Al-Quraishy SA. Diosmin attenuates methotrexate‐induced hepatic, renal, and cardiac injury: A biochemical and histopathological study in mice. Oxid Med Cell Longev. 2017;2017(1):3281670. https://doi.org/10.1155/2017/3281670.
35. Li S, Zhao Z. Thymoquinone alleviates cisplatin-induced kidney damage by reducing apoptosis in a rat model. Heliyon. 2024;10(2). https://doi.org/10.1016/j.heliyon.2024.e24840.
36. Behdokht B, Foad NM, Saeed N, Ahmadi N, Sakineh A. Comparative Study of the Protective Effects of Citral, Thymoquinone, and Silymarin on Methotrexate-induced Cardiotoxicity in Rats. J Pharmacopuncture. 2024;27(3):245-52. https://doi.org/10.3831/KPI.2024.27.3.245.
| Files | ||
| Issue | Vol 2026 No 4 (2) | |
| Section | Original Articles | |
| Keywords | ||
| Silymarin Citral Nephrotoxicity Thymoquinone Methotrexate | ||
| Rights and permissions | |
|
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |


