Serum markers of neuroinflammation and oxidative stress in modeling spinal injury of various genesis

Aim. To evaluate changes in the concentration of molecules that mark the neurodegenerative process, experimental spinal cord injuries (SCI) of various origins were studied.

Materials and methods. SCI was modeled in six-month-old male Wistar rats by exposing the T10 vertebra to: carbon dioxide under a pressure of 2 N/cm² (pneumocontusion); free-falling load of three weights of 1.12 N/cm², 1.68 N/cm², 1.96 N/cm² (contusion injury); compression with forceps (compression injury); partial hemisection of the spinal cord; mechanical laminectomy using a mechanical drill. There were 6 rats in each group, including the intact control group. On the 28th day after a single application of SCI in rats, the concentrations of tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), albumin, thiobarbituric acid reactive substances (TBA-RS) and superoxide dismutase activity were assessed in the blood serum.

Results. When modeling SCI of various origins in rats, the serum concentration of TNF-α increased (from 115.5% (p < 0.05) in mild contusion to 234.5% (p < 0.05) in compression trauma compared to intact control) as well as IL-6 (from 49.2% (p < 0.05) in mechanical laminectomy to 89.8% (p < 0.05) in hemisection compared with intact control), suggesting activation of inflammatory reactions. The concentration of albumin in the blood serum of rats with SCI was lower than that of intact animals, especially in the hemisection group – by 41.9% (p < 0.05). Animals with SCI had an increase in TBA-RS concentration ranging from 103.2% (p < 0.05) in mild contusion and compression to 135.5% (p < 0.05) in pneumocontusion, and a decrease in superoxide dismutase activity ranging from 26.3% (p < 0.05) in laminectomy to 31.7% (p < 0.05) in hemisection. At the same time, injuries caused by spinal compression and hemisection led to a more pronounced activation of the inflammatory process, as evidenced by the increased TNF-α content compared to other variants of SCI modeling.

Conclusion. All SCI simulations resulted in equivalent activation of oxidative stress, while inflammation is more pronounced when reproducing compression injury and injury caused by spinal hemisection.

1. Eli I., Lerner D.P., Ghogawala Z. Acute traumatic spinal cord injury. Neurol Clin. 2021 May; 39(2): 471–488. https://doi.org/10.1016/j.ncl.2021.02.004. Epub 2021 Mar 31. PMID: 33896529

2. Leemhuis E., Favieri F., Forte G., Pazzaglia M. Integrated neuroregenerative techniques for plasticity of the injured spinal cord. Biomedicines. 2022 Oct 13; 10(10): 2563. https://doi.org/10.3390/biomedicines10102563. PMID: 36289825; PMCID: PMC9599452

3. Ding W., Hu S., Wang P., et al. Spinal cord injury: the global incidence, prevalence, and disability from the Global Burden of Disease study 2019. Spine (Phila Pa 1976). 2022 Nov 1; 47(21): 1532–1540. https://doi.org/10.1097/BRS.0000000000004417. Epub 2022 Jun 30. PMID: 35857624

4. Гарифулин Р.Р., Измайлов А.А., Маркосян В.А. и др. Характеристика нейроглии в эпицентре и в удаленной от травмы области при контузионном повреждении спинного мозга у мини-свиньи. Сеченовский вестник. 2023; 14(3): 19–27. https://doi.org/10.47093/2218-7332.2023.14.3.19-27

5. Elliott C.S., Dallas K.B., Zlatev D., et al. Volitional voiding of the bladder after spinal cord injury: validation of bilateral lower extremity motor function as a key predictor. J Urol. 2018 Jul; 200(1): 154–160. https://doi.org/10.1016/j.juro.2018.02.064. Epub 2018 Feb 17. PMID: 29458066.

6. Ramalho B.D.S., de Almeida F.M., Martinez A.M.B. Cell therapy and delivery strategies for spinal cord injury. Histol Histopathol. 2021 Sep; 36(9): 907–920. https://doi.org/10.14670/HH-18-350. Epub 2021 Jun 10. PMID: 34109994

7. Liu Y., Liu J., Liu B. Identifi cation of Circular RNA expression profi les and their implication in spinal cord injury rats at the immediate phase. J Mol Neurosci. 2020 Nov; 70(11): 1894–1905. https://doi.org/10.1007/s12031-020-01586-9. Epub 2020 Jun 10. PMID: 32524420

8. Alizadeh A., Dyck S.M., Karimi-Abdolrezaee S. Traumatic spinal cord injury: an overview of pathophysiology, models and acute injury mechanisms. Front Neurol. 2019 Mar 22; 10: 282. https://doi.org/10.3389/fneur.2019.00282. PMID: 30967837; PMCID: PMC6439316

9. Huang Z., Wang J., Li C., et al. Application of natural antioxidants from traditional Chinese medicine in the treatment of spinal cord injury. Front Pharmacol. 2022 Oct 5; 13: 976757. https://doi.org/10.3389/fphar.2022.976757. PMID: 36278149; PMCID: PMC9579378

10. Sabirov D., Ogurcov S., Shulman I., et al. Comparative analysis of cytokine profi les in cerebrospinal fl uid and blood serum in patients with acute and subacute spinal cord injury. Biomedicines. 2023 Sep 26; 11(10): 2641. https://doi.org/10.3390/biomedicines11102641. PMID: 37893015; PMCID: PMC10604120

11. Sabirov D., Ogurcov S., Baichurina I., et al. Molecular diagnostics in neurotrauma: Are there reliable biomarkers and effective methods for their detection? Front Mol Biosci. 2022 Sep 29; 9: 1017916. https://doi.org/10.3389/fmolb.2022.1017916. PMID: 36250009; PMCID: PMC9557129

12. Anjum A., Yazid M.D., Fauzi Daud M., et al. Spinal cord injury: pathophysiology, multimolecular interactions, and underlying recovery mechanisms. Int J Mol Sci. 2020 Oct 13; 21(20): 7533. https://doi.org/10.3390/ijms21207533. PMID: 33066029; PMCID: PMC7589539

13. Tong B., Jutzeler C.R., Cragg J.J., et al. Serum albumin predicts long-term neurological outcomes after acute spinal cord injury. Neurorehabil Neural Repair. 2018 Jan; 32(1): 7–17. https://doi.org/10.1177/1545968317746781. Epub 2017 Dec 24. PMID: 29276840

14. Sheinenzon A., Shehadeh M., Michelis R., et al. Serum albumin levels and infl ammation. Int J Biol Macromol. 2021 Aug 1; 184: 857–862. https://doi.org/10.1016/j.ijbiomac.2021.06.140. Epub 2021 Jun 25. PMID: 34181998

15. Jha R.M., Kochanek P.M., Simard J.M. Pat hoph ysiology and treatment of cerebral edema in traumatic brain injury. Neuropharmacology. 2019 Feb; 145 (Pt B): 230–246. https://doi.org/10.1016/j.neuropharm.2018.08.004. Epub 2018 Aug 4. PMID: 30086289; PMCID: PMC6309515

16. Zhang C., Zhai T., Zhu J., et al. Research progress of antioxidants in oxidative stress therapy after spinal cord injury. Neurochem Res. 2023 Dec; 48(12): 3473–3484. https://doi.org/10.1007/s11064-023-03993-x. Epub 2023 Aug 1. PMID: 37526867

17. Frantsuzov R., Mondal S., Walsh C.M., et al. A fi nite element model of contusion spinal cord injury in rodents. J Mech Behav Biomed Mater. 2023 Jun; 142: 105856. https://doi.org/10.1016/j.jmbbm.2023.105856. Epub 2023 Apr 17. PMID: 37087955

18. Csomó K.B., Varga G., Belik A.A., et al. A minimally invasive, fast spinal cord lateral hemisection technique for modeling open spinal cord injuries in rats. J Vis Exp. 2022 Mar 23; (181). https://doi.org/10.3791/63534. PMID: 35404342

19. Marcol W., Slusarczyk W., Gzik M., et al. Air gun impactor−a novel model of graded white matter spinal cord injury in rodents. J. Reconstr. Microsurg. 2012 Oct; 28(8): 561–568. https://doi.org/10.1055/s-0032-1315779. Epub 2012 Jun 18. PMID: 22711195

20. Harikrishnan V.S., Krishnan L.K., Abelson K.S.P. A novel technique to develop thoracic spinal laminectomy and a methodology to assess the functionality and welfare of the contusion spinal cord injury (SCI) rat model. PLoS One. 2019 Jul 2; 14(7): e0219001. https://doi.org/10.1371/journal.pone.0219001. PMID: 31265469; PMCID: PMC6605676

21. Shen Y., Wang Y.P., Cheng X., et al. Autophagy regulation combined with stem cell therapy for treatment of spinal cord injury. Neural Regen Res. 2023 Aug; 18(8): 1629–1636. https://doi.org/10.4103/1673-5374.363189. PMID: 36751772; PMCID: PMC10154487

22. Kigerl K.A., Gensel J.C., Ankeny D.P., et al. Identifi cation of two distinct macrophage subsets with divergent effects causing either neurotoxicity or regeneration in the injured mouse spinal cord. J Neurosci. 2009 Oct 28; 29(43): 13435–13444. https://doi.org/10.1523/JNEUROSCI.3257-09.2009. PMID: 19864556; PMCID: PMC2788152

23. Tsikas D. Assessment of lipid peroxidation by measuring malondialdehyde (MDA) and relatives in biological samples: Analytical and biological challenges. Anal Biochem. 2017 May 1; 524: 13– 30. https://doi.org/10.1016/j.ab.2016.10.021. Epub 2016 Oct 24. PMID: 27789233

24. Kielkopf C.L., Bauer W., Urbatsch I.L. Bradford assay for determining protein concentration. Cold Spring Harb Protoc. 2020 Apr 1; 2020(4): 102269. https://doi.org/10.1101/pdb.prot102269. PMID: 32238597

25. Gumral N., Aslankoc R., Senol N., Cankara F.N. Protective effect of alpha-lipoic acid against liver damage induced by cigarette smoke: an in vivo study. Saudi J Med Med Sci. 2021 May-Aug; 9(2): 145–151. https://doi.org/10.4103/sjmms.sjmms_387_20. Epub 2021 Apr 29. PMID: 34084105; PMCID: PMC8152379

26. Doblado L.R., Martínez-Ramos C., Pradas M.M. Multimodular bio-inspired organized structures guiding long-distance axonal regeneration. Biomedicines. 2022 Sep 8; 10(9): 2228. https://doi.org/10.3390/biomedicines10092228. PMID: 36140328; PMCID: PMC9496454

27. Sun S., Li J., Wang S., et al. CHIT1-positive microglia drive motor neuron ageing in the primate spinal cord. Nature. 2023 Dec; 624(7992): 611–620. https://doi.org/10.1038/s41586-023-067831. Epub 2023 Oct 31. PMID: 37907096

28. Hu X., Xu W., Ren Y., et al. Spinal cord injury: molecular mechanisms and therapeutic interventions. Signal Transduct Target Ther. 2023 Jun 26; 8(1): 245. Published 2023 Jun 26. https://doi.org/10.1038/s41392-023-01477-6. PMID: 37357239; PMCID: PMC10291001

29. Kayabaş M., Şahin L., Makav M., et al. Protective effect of hydrogen-rich saline on spinal cord damage in rats. Pharmaceuticals (Basel). 2023 Apr 1; 16(4): 527. https://doi.org/10.3390/ph16040527. PMID: 37111284; PMCID: PMC10143771

30. Kung W.M., Chang C.J., Chen T.Y., Lin M.S. Cryogen spray cooling mitigates infl ammation and injury-induced CISD2 decline in rat spinal cord hemisection model. J Integr Neurosci. 2020 Dec 30; 19(4): 619–628. https://doi.org/10.31083/j.jin.2020.04.255. PMID: 33378836

31. Yu M., Wang Z., Wang D., et al. Oxidative stress following spinal cord injury: From molecular mechanisms to therapeutic targets. J Neurosci Res. 2023 Oct; 101(10): 1538–1554. https://doi.org/10.1002/jnr.25221. Epub 2023 Jun 5. PMID: