High-dose methylprednisolone in acute spinal cord injuries: proceed with caution

A Bibliometric Analysis of Publications on Spinal Cord Injury Treatment With Glucocorticoids Using VOSviewer

Background

Spinal cord injury (SCI) has devastating physical and social consequences for patients. Systemic administration of methylprednisolone (MP) at a higher dosage though can reduce neurological deficits following acute SCI. Still, this treatment regimen is controversial, owing to the apparent dose-related side effects and relatively minor improvement in neurological function. Therefore, this study aimed at the bibliometric analysis of published literature related to SCI treatment, which may lead to future research trends.

Methods

The literature published relating to SCI and using glucocorticoids for its treatment between 1982 and 2022 was collected and scanned in the Web of Science collection database using the keywords glucocorticoid, dexamethasone, MP, corticosteroids, and SCI, followed by using VOSviewer for bibliometric analysis of these articles.

Results

A total of 1,848 published articles and 7,448 authors on SCI and glucocorticoid usage were identified. The SCI total link strength accounts for 1,341, and MP for 762 has a strong link to neuroprotection and inflammation. The mean citation count for the top 20 most-cited articles was 682 (range: 358–1,828), where most of these were descriptive studies having focused on clinical features. The Journal of Neurotrauma was the highest-ranked journal with 6,010 citations. A total of 69 articles were published by Michael G Fehlings from the University of Toronto with 6,092 citations. The University of Toronto has published 90-related manuscripts with 7,632 citations. In contrast, 800 articles were published in the United States, with 39,633 citations and total link strength of 5,714. The second-ranked country was China, with 241 published articles and 3,403 citations.

Conclusions

The research published on applying MP in treating SCI has increased with time. Although the United States has made a significant global contribution to this important field of research, it requires rigorous clinical trials designed to verify the therapeutic role of MP in SCI and its appropriate dosage to find solutions for neurological recovery.

Transplantation of tauroursodeoxycholic acid-inducing M2-phenotype macrophages promotes an anti-neuroinflammatory effect and functional recovery after spinal cord injury in rats

Objectives

In this study, we study the transplantation of tauroursodeoxycholic acid (TUDCA)‐induced M2‐phenotype (M2) macrophages and their ability to promote anti‐neuroinflammatory effects and functional recovery in a spinal cord injury (SCI) model.

Methods

To this end, compared to the granulocyte‐macrophage colony‐stimulating factor (GM‐CSF), we evaluated whether TUDCA effectively differentiates bone marrow–derived macrophages (BMDMs) into M2 macrophages.

Results

The M2 expression markers in the TUDCA‐treated BMDM group were increased more than those in the GM‐CSF‐treated BMDM group. After the SCI and transplantation steps, pro‐inflammatory cytokine levels and the mitogen‐activated protein kinase (MAPK) pathway were significantly decreased in the TUDCA‐induced M2 group more than they were in the GM‐CSF‐induced M1 group and in the TUDCA group. Moreover, the TUDCA‐induced M2 group showed significantly enhanced tissue volumes and improved motor functions compared to the GM‐CSF‐induced M1 group and the TUDCA group. In addition, biotinylated dextran amine (BDA)–labelled corticospinal tract (CST) axons and neuronal nuclei marker (NeuN) levels were increased in the TUDCA‐induced M2 group more than those in the GM‐CSF‐induced M1 group and the TUDCA group.

Conclusions

This study demonstrates that the transplantation of TUDCA‐induced M2 macrophages promotes an anti‐neuroinflammatory effect and motor function recovery in SCI. Therefore, we suggest that the transplantation of TUDCA‐induced M2 macrophages represents a possible alternative cell therapy for SCI.

Current practice of methylprednisolone administration for acute spinal cord injury in Germany: a national survey

STUDY DESIGN

Written mail-out survey.

OBJECTIVE

To determine current practice in high-dose methylprednisolone succinate (MPSS) administration for treatment of acute spinal cord injury (SCI) in Germany.

SUMMARY OF BACKGROUND DATA

Reanalysis of the National Acute Spinal Cord Injury Studies (NASCIS) resulted in criticism of the use of high-dose MPSS for treatment of acute SCI. Subsequently, SCI treatment guidelines were revised leading to a reduction in MPSS use across North America. The impact of these revisions on SCI treatment in Germany is not known.

METHODS

A questionnaire was sent to all trauma, orthopedic and neurosurgical departments of German university centers, affiliated teaching hospitals, and specialized SCI care centers. Survey included 6 questions about the administration of MPSS after acute SCI.

RESULTS

Three hundred seventy-two respondents completed the survey (response rate: 51% overall, 76% university hospitals, 85% specialized SCI care centers). Overall, 55% of departments that treat SCI prescribe MPSS. Among them, 73% are "frequent" users administering MPSS to more than 50% of their patients. Ten percent prescribe according to NASCIS I, 43% NASCIS II, 33% NASCIS III, and 13% "generic protocols." As justification for MPSS treatment, "effectiveness" ranked before "common practice" and "medicolegal reasons." "Specialized" SCI care centers differ in that (1) MPSS is administered less frequently, (2) NASCIS I doses are not used, and (3) during the past several years, practice patterns are more likely to have shifted away from the treatment of SCI with MPSS.

CONCLUSION

About one-half of the institutions continue to prescribe MPSS in the setting of acute SCI. A need for further education in almost one-fourth of German departments treating acute SCI is demonstrated through responses indicating use of the outdated NASCIS I protocol, a "legal need" or "unchanged MPSS application during the last years." "Specialized" SCI centers are more likely to change their practice in accordance with evolving literature.

LEVEL OF EVIDENCE

3.

The therapeutic profile of rolipram, PDE target and mechanism of action as a neuroprotectant following spinal cord injury

The extent of damage following spinal cord injury (SCI) can be reduced by various neuroprotective regimens that include maintaining levels of cyclic adenosine monophosphate (cyclic AMP), via administration of the phosphodiesterase 4 (PDE4) inhibitor Rolipram. The current study sought to determine the optimal neuroprotective dose, route and therapeutic window for Rolipram following contusive SCI in rat as well as its prominent PDE target and putative mechanism of protection. Rolipram or vehicle control (10% ethanol) was given subcutaneously (s.c.) daily for 2 wk post-injury (PI) after which the preservation of oligodendrocytes, neurons and central myelinated axons was stereologically assessed. Doses of 0.1 mg/kg to 1.0 mg/kg (given at 1 h PI) increased neuronal survival; 0.5 mg to 1.0 mg/kg protected oligodendrocytes and 1.0 mg/kg produced optimal preservation of central myelinated axons. Ethanol also demonstrated significant neuronal and oligo-protection; though the preservation provided was significantly less than Rolipram. Subsequent use of this optimal Rolipram dose, 1.0 mg/kg, via different routes (i.v., s.c. or oral, 1 h PI), demonstrated that i.v. administration produced the most significant and consistent cyto- and axo- protection, although all routes were effective. Examination of the therapeutic window for i.v. Rolipram (1.0 mg/kg), when initiated between 1 and 48 h after SCI, revealed maximal neuroprotection at 2 h post-SCI, although the protective efficacy of Rolipram could still be observed when administration was delayed for up to 48 h PI. Importantly, use of the optimal Rolipram regimen significantly improved locomotor function after SCI as measured by the BBB score. Lastly we show SCI-induced changes in PDE4A, B and D expression and phosphorylation as well as cytokine expression and immune cell infiltration. We demonstrate that Rolipram abrogates SCI-induced PDE4B1 and PDE4A5 production, PDE4A5 phosphorylation, MCP-1 expression and immune cell infiltration, while preventing post-injury reductions in IL-10. This work supports the use of Rolipram as an acute neuroprotectant following SCI and defines an optimal administration protocol and target for its therapeutic application.