Stem Cell Therapy for Neurogenic Bladder Dysfunction in Rodent Models: A Systematic Review

Progress and research trends in neurogenic bladder after spinal cord injury bibliometric analysis based on web of science database: An observational study

Neurogenic bladder (NB) is a significant complication that often occurs after spinal cord injury. It results from urinary dysfunction caused by the injury, disrupting the normal neural control of the bladder and urethra. Symptoms of NB can include urinary frequency, urgency, incontinence, and retention, all of which can greatly impact the quality of life of affected individuals. While there are articles and reviews on NB, fewer specifically address NB following spinal cord injury. This study examined 1095 publications from January 1, 2000, to March 27, 2024, in the Web of Science core database using bibliometric software like VOSviewer, CiteSpace, and Bibliometrics. The analysis revealed an increasing trend in the number of publications, with the United States and China leading in research output. Professor Jeremy B. Myers from the University of Utah had the highest number of publications, while the University of Michigan and the University of Pittsburgh were the institutions with the most publications. The journal Neurourology and Urodynamics had the highest number of articles, and common keywords included management, quality of life, and dysfunction, highlighting key areas of focus for scholars.

Tissue Engineering and Stem Cell Therapy in Neurogenic Bladder Dysfunction: Current and Future Perspectives

Tissue engineering (TE) is a rapidly evolving biomedical discipline that can play an important role in treating neurogenic bladder dysfunction and compensating for current conventional options' shortcomings. This review aims to analyze the current status of preclinical and clinical trials and discuss what could be expected in the future based on the current state of the art. Although most preclinical studies provide promising results on the effectiveness of TE and stem cell therapies, the main limitations are mainly the very slow translation of preclinical trials to clinical trials, lack of quality research on neurogenic preconditions of neurogenic bladder dysfunction outside of the spinal cord injury and varying therapeutic methods of the existing research that lacks a standardized approach.

Gap Junction-Mediated Transport of Metabolites Between Stem Cells and Vascular Endothelial Cells

We have previously demonstrated that small molecular transfer, such as glucose, between hematopoietic stem cells (HSCs) or mesenchymal stem cells (MSCs) and vascular endothelial cells via gap junctions constitutes an important mechanism of stem cell therapy. Cell metabolites are high-potential small-molecule candidates that can be transferred to small molecules between stem cells and vascular endothelial cells. Here, we investigated the differences in metabolite levels between stem cells (HSCs and MSCs), vascular endothelial cells, and the levels of circulating non-hematopoietic white blood cells (WBCs). The results showed remarkable differences in metabolite concentrations between cells. Significantly higher concentrations of adenosine triphosphate (ATP), guanosine triphosphate (GTP), total adenylate or guanylate levels, glycolytic intermediates, and amino acids were found in HSCs compared with vascular endothelial cells. In contrast, there was no significant difference in the metabolism of MSCs and vascular endothelial cells. From the results of this study, it became clear that HSCs and MSCs differ in their metabolites. That is, metabolites that transfer between stem cells and vascular endothelial cells differ between HSCs and MSCs. HSCs may donate various metabolites, several glycolytic and tricarboxylic acid cycle metabolites, and amino acids to damaged vascular endothelial cells as energy sources and activate the energy metabolism of vascular endothelial cells. In contrast, MSCs and vascular endothelial cells regulate each other under normal conditions. As the existing MSCs cannot ameliorate the dysregulation during insult, exogenous MSCs administered by cell therapy may help restore normal metabolic function in the vascular endothelial cells by taking up excess energy sources from the lumens of blood vessels. Results of this study suggested that the appropriate timing of cell therapy is different between HSCs and MSCs.

Human umbilical cord mesenchymal stem cells contribute to the reconstruction of bladder function after acute spinal cord injury via p38 mitogen-activated protein kinase/nuclear factor-kappa B pathway

The association between spinal cord injury (SCI) and bladder symptoms has been intensively described. Human umbilical cord mesenchymal stem cell (hUC-MSC) treatment is beneficial to the recovery of bladder function after SCI, but its mechanism is unclear. We established an SCI model, and prepared hUC-MSCs in advance, followed by verification using flow cytometry. The Basso, Beattie and Bresnahan (BBB) score and urodynamic index were employed to evaluate motor function and bladder functions, respectively. Hematoxylin-eosin staining, luxol fast blue staining, and Masson's trichrome staining were utilized to assess pathological changes. Real-time quantitative PCR and Western blot were used to determine the mRNA and protein expressions in bladder tissues. The immunophenotypes of the HUC-MSCs were CD90⁺ and CD105⁺, but CD34^-, CD45^- and HLA-DR^-. Rats appeared severe motor dysfunction after SCI, but the BBB score was increased in hUC-MSCs after the second week. Pathologically, the improvement of the lesion area on the dorsal spinal cord, augmented anterior gray horn neuron cells of the spinal cord and lessened bladder tissue remodeling (fibrosis, collagen deposition) as well as modulated inflammation could be observed. Besides, SCI increased bladder weight, bladder capacity, urine volume and residual urine volume, and decreased urination efficiency. HUC-MSCs ameliorated SCI-induced pathological changes and bladder functions, the expressions of Collagen I, Collagen III, fibroblast growth factor 2 (FGF2), phospho-p38, transient receptor potential vanilloid 1, Toll-like receptor 4 and phospho-nuclear factor-kappa B (p-NF-κB). To sum up, HUC-MSCs contribute to the reconstruction of bladder function after SCI by repressing p38 MAPK/NF-κB pathway.

Clinical application of stem cell therapy in neurogenic bladder: a systematic review and meta-analysis

INTRODUCTION AND HYPOTHESIS

This review aims to investigate the effect of stem cell (SC) therapy on the management of neurogenic bladder (NGB) in four neurological diseases, including spinal cord injury (SCI), Parkinson's disease (PD), multiple sclerosis (MS), and stroke, in the clinical setting.

METHODS

An electronic database search was conducted in the Cochrane Library, EMBASE, Proquest, Clinicaltrial.gov , WHO, Google Scholar, MEDLINE via PubMed, Ovid, Web of Science, Scopus, ongoing trial registers, and conference proceedings in June 2019 and updated by hand searching on 1 February 2021. All randomized controlled trials (RCTs), quasi RCTs, phase I/II clinical trials, case-control, retrospective cohorts, and comprehensive case series that evaluated the regenerative potential of SCs on the management of NGB were included. Cochrane appraisal risk of bias checklist and the standardized critical appraisal instrument from the JBI Meta-Analysis of Statistics, Assessment, and Review Instrument (JBI-MAStARI) were used to appraise the studies.

RESULTS

Twenty-six studies among 1282 relevant publications met our inclusion criteria. Only SC therapy was applied for SCI or MS patients. Phase I/II clinical trials (without control arm) were the most conducted studies, and only four were RCTs. Four studies with 153 participants were included in the meta-analysis. The main route of transplantation was via lumbar puncture. There were no serious adverse events. Only nine studies in SCI and one in MS have used urodynamics, and the others have reported improvement based on patient satisfaction. SC therapy did not significantly improve residual urine volume, detrusor pressure, and maximum bladder capacity. Also, the quality of these publications was low or unclear.

CONCLUSION

Although most clinical trials provide evidence of the safety and effectiveness of MSCs on the management of NGB, the meta-analysis results did not show a significant improvement; however, the interpretation of study results is difficult because of the lack of placebo controls.

Nicotinamide promotes pancreatic differentiation through the dual inhibition of CK1 and ROCK kinases in human embryonic stem cells

Background

Vitamin B3 (nicotinamide) plays important roles in metabolism as well as in SIRT and PARP pathways. It is also recently reported as a novel kinase inhibitor with multiple targets. Nicotinamide promotes pancreatic cell differentiation from human embryonic stem cells (hESCs). However, its molecular mechanism is still unclear. In order to understand the molecular mechanism involved in pancreatic cell fate determination, we analyzed the downstream pathways of nicotinamide in the derivation of NKX6.1⁺ pancreatic progenitors from hESCs.

Methods

We applied downstream modulators of nicotinamide during the induction from posterior foregut to pancreatic progenitors, including niacin, PARP inhibitor, SIRT inhibitor, CK1 inhibitor and ROCK inhibitor. The impact of those treatments was evaluated by quantitative real-time PCR, flow cytometry and immunostaining of pancreatic markers. Furthermore, CK1 isoforms were knocked down to validate CK1 function in the induction of pancreatic progenitors. Finally, RNA-seq was used to demonstrate pancreatic induction on the transcriptomic level.

Results

First, we demonstrated that nicotinamide promoted pancreatic progenitor differentiation in chemically defined conditions, but it did not act through either niacin-associated metabolism or the inhibition of PARP and SIRT pathways. In contrast, nicotinamide modulated differentiation through CK1 and ROCK inhibition. We demonstrated that CK1 inhibitors promoted the generation of PDX1/NKX6.1 double-positive pancreatic progenitor cells. shRNA knockdown revealed that the inhibition of CK1α and CK1ε promoted pancreatic progenitor differentiation. We then showed that nicotinamide also improved pancreatic progenitor differentiation through ROCK inhibition. Finally, RNA-seq data showed that CK1 and ROCK inhibition led to pancreatic gene expression, similar to nicotinamide treatment.

Conclusions

In this report, we revealed that nicotinamide promotes generation of pancreatic progenitors from hESCs through CK1 and ROCK inhibition. Furthermore, we discovered the novel role of CK1 in pancreatic cell fate determination.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02426-2.

Evaluation of PTEN Inhibitor Following Spinal Cord Injury on Recovery of Voiding Efficiency and Motor Function Observed by Regeneration in Spinal Cord

PURPOSE

Neurogenic bladder (NB) associated with spinal cord injury (SCI) is a serious health problem. However, no effective treatment has been developed for SCI patients with NB. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) inhibitors have been proposed as a promising option for inducing neural regeneration. Therefore, we investigated the effects of a tissue gene nerve (TGN), PTEN inhibitor, on voiding function, motor function, and the expression of growth factors after SCI.

METHODS

In this experiment, female rats were randomly divided into 3 groups (n=10 in each group): the sham-operation group, the SCI-induced group, and the SCI-induced and TGN-treated group. Cystometry; the Basso, Beattie, and Bresnahan (BBB) scale test; the ladder walking test; hematoxylin and eosin staining; and Western blotting for brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF), and nerve growth factor (NGF) were performed to evaluate functional and molecular changes.

RESULTS

After SCI, the rats exhibited decreased walking ability according to the BBB scale test and impaired coordinative function according to the ladder walking test. The PTEN inhibitor promoted enhanced walking ability and coordinative function. Cystometry showed voiding impairment after SCI and improved voiding function was observed after PTEN treatment. Overexpression of VEGF, BDNF, and NGF were observed after SCI. Administration of PTEN inhibitors significantly attenuated the overexpression of growth factors due to SCI.

CONCLUSION

PTEN inhibitor treatment diminished the overexpression of growth factors and promoted the repair of damaged tissue. PTEN inhibitor-treated rats also showed improved motor function and improved voiding function. Therefore, we suggest TGN as a new therapeutic agent that can be applied after SCI.