Clinical and Histopathological Effects of Isotretinoin on Neuroregeneration in Experimental Spinal Cord Injury

Abstract

Aim: Spinal cord injury is an important problem, and a fully effective treatment for it has not yet been developed. Isotretinoin is a retinoid known for its anti-inflammatory effect. The present study aimed to evaluate whether isotretinoin has a positive impact on neural tissue in post-injury damage. Material and Methods: A total of 36 rats were randomly divided into 6 groups as control, sham, and injury with 14-day 7.5 mg/kg/day, 28-day 7.5 mg/kg/day, 14-day 15 mg/kg/day, and 28-day 15 mg/kg/day isotretinoin groups. Laminectomy was performed and spinal cord injury was produced by using the clip compression technique. Neurological examination was performed on days 1, 7, 14, and 28. After the treatment period, all rats were sacrificed, and their spinal cord samples were collected for histopathological assessment. Results: Groups receiving 7.5 mg/kg/day (p=0.048) and 15 mg/kg/day (p<0.001) isotretinoin showed a significantly increased inclined plane angle on day 14 compared with the sham group. In hematoxylin and eosin, and Luxol fast blue staining, the 28-day isotretinoin of 15 mg/kg/day group and the control group had similar histopathological findings in motor neurons and glial cells. The cleaved caspase 3 expression was significantly diminished in the groups of 28-day isotretinoin 7.5 mg/kg/day, 14-day isotretinoin 15 mg/kg/day, and 28-day isotretinoin 15 mg/kg/day, compared to the sham group, along with the reduction in apoptosis. Conclusion: Isotretinoin reduces neuronal apoptosis, diminishes pathological tissue damage, and improves functional recovery after injury. The observed prominent neuroprotective effects introduce isotretinoin as a promising therapy for spinal cord injury.

Keywords

• Isotretinoin
• Neuroregeneration
• Spinal cord injury

Deneysel Omurilik Yaralanmasında İsotretinoinin Nörorejenerasyon Üzerine Klinik ve Histopatolojik Etkileri

Abstract

Amaç: Omurilik yaralanması önemli bir sorundur ve henüz tam olarak etkili bir tedavi geliştirilememiştir. İsotretinoin, anti-inflamatuar etkisiyle bilinen bir retinoiddir. Bu çalışmanın amacı, yaralanma sonrası sinir dokusu üzerinde isotretinoinin olumlu bir etkisinin olup olmadığını değerlendirmektir. Gereç ve Yöntemler: Toplam 36 sıçan kontrol, sham ve travma ile 14 günlük 7,5 mg/kg/gün, 28 günlük 7,5 mg/kg/gün, 14 günlük 15 mg/kg/gün ve 28 günlük 15 mg/kg/gün isotretinoin grupları olmak üzere 6 gruba ayrıldı. Sıçanlara laminektomi yapıldı ve omurilik yaralanması klip kompresyon tekniği kullanılarak oluşturuldu. Nörolojik muayene 1, 7, 14 ve 28. günlerde yapıldı. Tedavi süresinden sonra tüm sıçanlar öldürüldü ve histopatolojik değerlendirme için omurilik örnekleri toplandı. Bulgular: 7,5 mg/kg/gün (p=0,048) ve 15 mg/kg/gün (p<0,001) isotretinoin alan gruplar, sham grubuna kıyasla 14. günde önemli ölçüde artmış eğik düzlem açısı gösterdi. Hematoksilen ve eozin ile Luxol fast blue ile boyamada 15 mg/kg/gün isotretinoin 28 günlük grubu ve kontrol grubunun motor nöronlarında ve glial hücrelerinde benzer histopatolojik bulgular görüldü. Cleaved kaspaz 3 ekspresyonu, sham grubuna kıyasla 28 günlük isotretinoin 7,5 mg/kg/gün, 14 günlük isotretinoin 15 mg/kg/gün ve 28 günlük isotretinoin 15 mg/kg/gün gruplarında anlamlı bir şekilde azaldı ve apoptozisde azalma olduğu görüldü. Sonuç: İsotretinoin, nöronal apoptozu azaltır, patolojik doku hasarını azaltır ve yaralanma sonrası fonksiyonel iyileşmeye etki eder. Gözlemlenen belirgin nöroprotektif etkiler, isotretinoini omurilik yaralanması için umut verici bir tedavi olarak tanıtmaktadır.

Keywords

• İsotretinoin
• Nörorejenerasyon
• Omurilik yaralanması

References

1. Yang R, Cai X, Li J, Liu F, Sun T. Protective effects of mir-129-5p on acute spinal cord injury rats. Med Sci Monit. 2019;25:8281-8.
2. Aytar MH, Civi S, Kaymaz M, Ergun E, Kaymaz FF, Pasaoglu A. The effect of quetiapine on treatment of experimental acute spinal cord injury. Turk Neurosurg. 2018;28(1):105-10.
3. Schwab ME, Bartholdi D. Degeneration and regeneration of axons in the lesioned spinal cord. Physiol Rev. 1996;76(2):319-70.
4. Demediuk P, Saunders RD, Clendenon NR, Means ED, Anderson DK, Horrocks LA. Changes in lipid metabolism in traumatized spinal cord. Prog Brain Res. 1985;63:211-26.
5. Tator CH. Review of experimental spinal cord injury with emphasis on the local and systemic circulatory effects. Neurochirurgie. 1991;37(5):291-302.
6. Kwon BK, Tetzlaff W, Grauer JN, Beiner J, Vaccaro AR. Pathophysiology and pharmacologic treatment of acute spinal cord injury. Spine J. 2004;4(4):451-64.
7. Karadağ AS. İzotretinoin. In: Sarıcaoğlu H, Ünal İ, Karaman G, Ferahbaş Kesikoğlu A, Karadağ, Şikar Aktürk A, et al., editors. Akne ve Rozase Tanı ve Tedavi, İstanbul: Galenos Yayınevi, 2018. p:242-58.
8. Bagatin E, Costa CS. The use of isotretinoin for acne - an update on optimal dosing, surveillance, and adverse effects. Expert Rev Clin Pharmacol. 2020;13(8):885-97.

9. Melnik BC. The role of transcription factor FoxO1 in the pathogenesis of acne vulgaris and the mode of isotretinoin action. G Ital Dermatol Venereol. 2010;145(5):559-71.
10. Karadag AS, Ertugrul DT, Bilgili SG, Takci Z, Akin KO, Calka O. Immunoregulatory effects of isotretinoin in patients with acne. Br J Dermatol. 2012;167(2):433-5.
11. Papakonstantinou E, Aletras AJ, Glass E, Tsogas P, Dionyssopoulos A, Adjaye J, et al. Matrix metalloproteinases of epithelial origin in facial sebum of patients with acne and their regulation by isotretinoin. J Invest Dermatol. 2005;125(4):673-84.
12. Thielitz A, Krautheim A, Gollnick H. Update in retinoid therapy of acne. Dermatol Ther. 2006;19(5):272-9.
13. Zouboulis CC. Isotretinoin revisited: pluripotent effects on human sebaceous gland cells. J Invest Dermatol. 2006;126(10):2154-6.
14. Kılıç G, Polat Ö, Şensoy G, Soylu H. Effects of isotretinoin and acitretin on neuroregeneration in experimental spinal cord injury. Acta Orthop Traumatol Turc. 2023;57(4):127-33.
15. Tascioglu T, Karatay M, Erdem Y, Tekiner A, Celik H, Sahin O, et al. Simvastatin in an experimental spinal cord injury model: a histopathological and biochemical evidence based study. Bratisl Lek Listy. 2020;121(10):722-6.
16. Rivlin AS, Tator CH. Objective clinical assessment of motor function after experimental spinal cord injury in the rat. J Neurosurg 1977;47(4):577-81.
17. Gürkan G, Sayin M, Kizmazoglu C, Erdogan MA, Yigitturk G, Erbak Yilmaz H, et al. Evaluation of the neuroprotective effects of ozone in an experimental spine injury model. J Neurosurg Spine. 2020;33(3):406-14.
18. Amar AP, Levy ML. Pathogenesis and pharmacological strategies for mitigating secondary damage in acute spinal cord injury. Neurosurgery. 1999;44(5):1027-40.
19. Lou J, Lenke LG, Ludwig FJ, O'Brien MF. Apoptosis as a mechanism of neuronal cell death following acute experimental spinal cord injury. Spinal Cord. 1998;36(10):683-90.
20. Lu J, Ashwell KW, Waite P. Advances in secondary spinal cord injury: Role of Apoptosis. Spine (Phila Pa 1976). 2000;25(14):1859-66.
21. Adams JM, Cory S. Life-or-death decisions by the Bcl-2 protein family. Trends Biochem Sci. 2001;26(1):61-6.
22. Curtin JF, Cotter TG. Live and let die: regulatory mechanisms in Fas-mediated apoptosis. Cell Signal. 2003;15(11):983-92.
23. Dumont RJ, Okonkwo DO, Verma S, Hurlbert RJ, Boulos PT, Ellegala DB, et al. Acute spinal cord injury, part I: pathophysiologic mechanisms. Clin Neuropharmacol. 2001;24(5):254-64.
24. Yakovlev AG, Faden AI. Sequential expression of c-fos protooncogene, TNF-alpha, and dynorphin genes in spinal cord following experimental traumatic injury. Mol Chem Neuropathol. 1994;23(2-3):179-90.
25. Hausmann O. Post-traumatic inflammation following spinal cord injury. Spinal Cord. 2003;41(7):369-78.
26. Arac D, Erdi MF, Keskin F, Kenan M, Cuce G, Aydemir FHY, et al. Neuroprotective effects of milrinone on experimental acute spinal cord injury: rat model. World Neurosurg. 2021;147:e225-33.
27. Rossignol S, Schwab M, Schwartz M, Fehlings MG. Spinal cord injury: time to move? J Neurosci. 2007;27(44):11782-92.
28. Topsakal C, Erol FS, Ozveren MF, Yilmaz N, Ilhan N. Effects of methylprednisolone and dextromethorphan on lipid peroxidation in an experimental model of spinal cord injury. Neurosurg Rev. 2002;25(4):258-66.
29. Mollan SP, Woodcock M, Siddiqi R, Huntbach J, Good P, Scott RA. Does use of isotretinoin rule out a career in flying? Br J Ophthalmol. 2006;90(8):957-9.
30. Goldsmith LA, Bolognia JL, Callen JP, Chen SC, Feldman SR, Lim HW, et al. American Academy of Dermatology Consensus Conference on the safe and optimal use of isotretinoin: summary and recommendations. J Am Acad Dermatol. 2004;50(6):900-6.