**5. Conclusions**

Treatment of SCI with the bile acid TUDCA reduces inflammation and improves recovery of autonomic and motor functions in the subacute phase. No lasting therapeutic benefits were observed in the chronic phase or in combinatorial treatment with bmSC. Therefore, our data do not support the use of TUDCA as a treatment of SCI, at least when this is done in the acute phase only. The efficacy of alternative agonists of the bile acid receptors TGR5 and FXR should be investigated.

**Supplementary Materials:** The following are available online at https://www.mdpi.com/article/10 .3390/biomedicines10071501/s1, Table S1: Effect of SCI and TUDCA treatment on the expression of genes associated with microglial activation; Figure S1: SCI-induced apoptosis as shown with TUNEL staining.

**Author Contributions:** Conceptualization, J.M., L.R.-R. and B.W.K.; investigation, S.W., J.M. and C.G.-R.; resources, J.M., L.R.-R., J.P.J.M.d.M. and E.C.W.; writing-original draft preparation, J.M.; writing-review and editing, J.M., L.R.-R. and B.W.K.; visualization, J.M.; supervision, J.M. and L.R.-R.; funding acquisition, J.M. and L.R.-R. All authors have read and agreed to the published version of the manuscript.

**Funding:** The study was funded by national research gran<sup>t</sup> SAF2017-89366-R (MINECO, AEI/FEDER /UE; Spain) to J.M. and L.R.-R., S.W. received a PhD scholarship from the Chinese Scholarship Council, award 201606300031. Publishing costs were paid by the Hospital Nacional de Parapléjicos/Servicio de Salud de Castilla la Mancha.

**Institutional Review Board Statement:** The animal study protocol was approved by the Institutional Ethics Committee of the Hospital Nacional de Parapléjicos (163CEEA/2017). All procedures for collection of human bone marrow were approved by the ethics committee of Maastricht University Medical Center (METC 13-2-032).

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data supporting the reported results are available from the corresponding author upon reasonable request.

**Acknowledgments:** The Animal, Cytometry and Microscopy core facilities of the HNP and their staff provided excellent technical service. Natalia Díaz Rubio helped with data evaluation.

**Conflicts of Interest:** J.P.J.M.d.M. and E.C.W. are co-owners of Neuroplast BV. S.W., C.G.-R., L.R.-R., B.W.K. and J.M. declare that they have no conflict of interest.
