Verification of mesenchymal stem cell injection therapy for interstitial cystitis in a rat model

Promising Experimental Treatment in Animal Models and Human Studies of Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis/bladder pain Syndrome (IC/BPS) remains a mysterious and intricate urological disorder, presenting significant challenges to healthcare providers. Traditional guidelines for IC/BPS follow a hierarchical model based on symptom severity, advocating for conservative interventions as the initial step, followed by oral pharmacotherapy, intravesical treatments, and, in refractory cases, invasive surgical procedures. This approach embraces a multi-tiered strategy. However, the evolving understanding that IC/BPS represents a paroxysmal chronic pain syndrome, often involving extravesical manifestations and different subtypes, calls for a departure from this uniform approach. This review provides insights into recent advancements in experimental strategies in animal models and human studies. The identified therapeutic approaches fall into four categories: (i) anti-inflammation and anti-angiogenesis using monoclonal antibodies or immune modulation, (ii) regenerative medicine, including stem cell therapy, platelet-rich plasma, and low-intensity extracorporeal shock wave therapy, (iii) drug delivery systems leveraging nanotechnology, and (iv) drug delivery systems assisted by energy devices. Future investigations will require a broader range of animal models, studies on human bladder tissues, and well-designed clinical trials to establish the efficacy and safety of these therapeutic interventions.

Therapeutic Approaches for Urologic Chronic Pelvic Pain Syndrome; Management: Research Advances, Experimental Targets, and Future Directions

Urologic chronic pelvic pain syndrome (UCPPS) is a painful chronic condition with persistent pain originating from the pelvis that often leads to detrimental lifestyle changes in the affected patients. The syndrome develops in both sexes, with an estimated prevalence of 5.7% to 26.6% worldwide. This narrative review summarizes currently recommended therapies for UCPPS, followed by the latest animal model findings and clinical research advances in the field. The diagnosis of UCPPS by clinicians has room for improvement despite the changes in the past decade aiming to decrease the time to treatment. Therapeutic approaches targeting growth factors (i.e., nerve growth factor, vascular endothelial growth factor), amniotic bladder therapy, and stem cell treatments gain more attention as experimental treatment options for UCPPS. The development of novel diagnostic tests based on the latest advances in urinary biomarkers would be beneficial to assist with the clinical diagnosis of UCPPS. Future research directions should address the role of chronic psychologic stress and the mechanisms of pain refractory to conventional management strategies in UCPPS etiology. Testing the applicability of cognitive behavioral therapy in this cohort of UCPPS patients might be promising to increase their quality of life. The search for novel lead compounds and innovative drug delivery systems requires clinically relevant translational animal models. The role of autoimmune responses triggered by environmental factors is another promising research direction to clarify the impact of the immune system in UCPPS pathophysiology. SIGNIFICANCE STATEMENT: This minireview provides an up-to-date summary of the therapeutic approaches for UCPPS with a focus on recent advancements in the clinical diagnosis and treatments of the disease, pathophysiological mechanisms of UCPPS, signaling pathways, and molecular targets involved in pelvic nociception.

In vivo safety and biodistribution profile of Klotho-enhanced human urine-derived stem cells for clinical application

BACKGROUND

Urine-derived stem cells (UDSCs) can be easily isolated from urine and possess excellent stem cell characteristics, making them a promising source for cell therapeutics. Due to their kidney origin specificity, UDSCs are considered a superior therapeutic alternative for kidney diseases compared to other stem cells. To enhance the therapeutic potential of UDSCs, we developed a culture method that effectively boosts the expression of Klotho, a kidney-protective therapeutic factor. We also optimized the Good Manufacturing Practice (GMP) system to ensure stable and large-scale production of clinical-grade UDSCs from patient urine. In this study, we evaluated the in vivo safety and distribution of Klotho-enhanced UDSCs after intravenous administration in accordance with Good Laboratory Practice (GLP) regulations.

METHODS

Mortality and general symptoms were continuously monitored throughout the entire examination period. We evaluated the potential toxicity of UDSCs according to the administration dosage and frequency using clinical pathological and histopathological analyses. We quantitatively assessed the in vivo distribution and retention period of UDSCs in major organs after single and repeated administration using human Alu-based qPCR analysis. We also conducted long-term monitoring for 26 weeks to assess the potential tumorigenicity.

RESULTS

Klotho-enhanced UDSCs exhibited excellent homing potential, and recovered Klotho expression in injured renal tissue. Toxicologically harmful effects were not observed in all mice after a single administration of UDSCs. It was also verified that repeated administration of UDSCs did not induce significant toxicological or immunological adverse effects in all mice. Single and repeated administrated UDSCs persisted in the blood and major organs for approximately 3 days and cleared in most organs, except the lungs, within 2 weeks. UDSCs that remained in the lungs were cleared out in approximately 4-5 weeks. There were no significant differences according to the variation of sex and administration frequency. The tumors were found in the intravenous administration group but they were confirmed to be non-human origin. Based on these results, it was clarified that UDSCs have no tumorigenic potential.

CONCLUSIONS

Our results demonstrate that Klotho-enhanced UDSCs can be manufactured as cell therapeutics through an optimized GMP procedure, and they can be safely administered without causing toxicity and tumorigenicity.

Body fluid-derived stem cells - an untapped stem cell source in genitourinary regeneration

Somatic stem cells have been obtained from solid organs and tissues, including the bone marrow, placenta, corneal stroma, periosteum, adipose tissue, dental pulp and skeletal muscle. These solid tissue-derived stem cells are often used for tissue repair, disease modelling and new drug development. In the past two decades, stem cells have also been identified in various body fluids, including urine, peripheral blood, umbilical cord blood, amniotic fluid, synovial fluid, breastmilk and menstrual blood. These body fluid-derived stem cells (BFSCs) have stemness properties comparable to those of other adult stem cells and, similarly to tissue-derived stem cells, show cell surface markers, multi-differentiation potential and immunomodulatory effects. However, BFSCs are more easily accessible through non-invasive or minimally invasive approaches than solid tissue-derived stem cells and can be isolated without enzymatic tissue digestion. Additionally, BFSCs have shown good versatility in repairing genitourinary abnormalities in preclinical models through direct differentiation or paracrine mechanisms such as pro-angiogenic, anti-apoptotic, antifibrotic, anti-oxidant and anti-inflammatory effects. However, optimization of protocols is needed to improve the efficacy and safety of BFSC therapy before therapeutic translation.

Caftaric Acid Ameliorates Oxidative Stress, Inflammation, and Bladder Overactivity in Rats Having Interstitial Cystitis: An In Silico Study

Interstitial cystitis (IC) is the principal unwanted effect associated with the use of cyclophosphamide (CYP). It results in increased oxidative stress, overexpression of proinflammatory cytokines, and bladder overactivity. Patients receiving CYP treatment had severely depreciated quality of life, as the treatment available is not safe and effective. The goal of this study was to assess the protective effect of caftaric acid in CYP-induced IC. IC was induced in female Sprague Dawley by injecting CYP (150 mg/kg, i.p.). In the present study, oral administration of caftaric acid (20, 40, and 60 mg/kg) significantly decreased inflammation. Caftaric acid significantly increased SOD (93%), CAT (92%), and GSH (90%) while decreased iNOS (97%), IL-6 (90%), TGF 1-β (83%), and TNF-α (96%) compared to the diseased. DPPH assay showed the antioxidant capacity comparable to ascorbic acid. Molecular docking of caftaric acid with selected protein targets further confirmed its antioxidant and anti-inflammatory activities. The cyclophosphamide-induced bladder overactivity had been decreased possibly through the inhibition of M3 receptors, ATP-sensitive potassium channels, calcium channels, and COX enzyme by caftaric acid. Therefore, our findings demonstrate that caftaric acid has a considerable protective role against CYP-induced IC by decreasing the oxidative stress, inflammation, and bladder smooth muscle hyperexcitability. Thus, caftaric acid signifies a likely adjuvant agent in CYP-based chemotherapy treatments.

Spasmolytic and Uroprotective Effects of Apigenin by Downregulation of TGF-β and iNOS Pathways and Upregulation of Antioxidant Mechanisms: In Vitro and In Silico Analysis

Apigenin is a phytochemical obtained from Chamomilla recutita. Its role in interstitial cystitis is not yet known. The present study is aimed at understanding the uroprotective and spasmolytic effects of apigenin in cyclophosphamide-induced interstitial cystitis. The uroprotective role of apigenin was analyzed by qRT-PCR, macroscopic analysis, Evans blue dye leakage, histological evaluation, and molecular docking. The spasmolytic response was measured by adding cumulative concentrations of apigenin to isolated bladder tissue pre-contracted with KCl (80 mM) and carbachol (10^-9-10^-4) on non-incubated and pre-incubated tissues with atropine, 4DAMP, methoctramine, glibenclamide, barium chloride, nifedipine, indomethacin, and propranolol. Apigenin inhibited pro-inflammatory cytokines (IL-6, TNF-α and TGF 1-β) and oxidant enzymes (iNOS) while increasing antioxidant enzymes (SOD, CAT, and GSH) in CYP-treated groups compared to the control. Apigenin restored normal tissue of the bladder by decreasing pain, edema, and hemorrhage. Molecular docking further confirmed the antioxidant and anti-inflammatory properties of apigenin. Apigenin produced relaxation against carbachol-mediated contractions, probably via blockade of M₃ receptors, K_ATP channels, L-type calcium channels, and prostaglandin inhibition. While the blockade of M₂ receptors, K_IR channels, and β-adrenergic receptors did not contribute to an apigenin-induced spasmolytic effect, apigenin presented as a possible spasmolytic and uroprotective agent with anti-inflammatory, antioxidant effects by attenuating TGF-β/iNOS-related tissue damage and bladder muscle overactivity. Thus, it is a potential agent likely to be used in treatment of interstitial cystitis.

Mesenchymal stem cells limit vascular and epithelial damage and restore the impermeability of the urothelium in chronic radiation cystitis

BACKGROUND

Cellular therapy seems to be an innovative therapeutic alternative for which mesenchymal stem cells (MSCs) have been shown to be effective for interstitial and hemorrhagic cystitis. However, the action of MSCs on chronic radiation cystitis (CRC) remains to be demonstrated. The aim of this study was to set up a rat model of CRC and to evaluate the efficacy of MSCs and their mode of action.

METHODS

CRC was induced by single-dose localized irradiation of the whole bladder using two beams guided by tomography in female Sprague-Dawley rat. A dose range of 20-80 Gy with follow-up 3-12 months after irradiation was used to characterize the dose effect and the kinetics of radiation cystitis in rats. For the treatment, the dose of 40 Gy was retained, and in order to potentiate the effect of the MSCs, MSCs were isolated from adipose tissue. After expansion, they were injected intravenously during the pre-chronic phase. Three injections of 5 million MSCs were administered every fortnight. Follow-up was performed for 12 months after irradiation.

RESULTS

We observed that the intensity and frequency of hematuria are proportional to the irradiation dose, with a threshold at 40 Gy and the appearance of bleeding from 100 days post-irradiation. The MSCs reduced vascular damage as well as damage to the bladder epithelium.

CONCLUSIONS

These results are in favor of MSCs acting to limit progression of the chronic phase of radiation cystitis. MSC treatment may afford real hope for all patients suffering from chronic radiation cystitis resistant to conventional treatments.

The Efficacy and Safety of a Human Perirenal Adipose Tissue-Derived Stromal Vascular Fraction in an Interstitial Cystitis Rat Model

BACKGROUND

Interstitial cystitis (IC) is a chronic and intractable disease that can severely deteriorate patients' quality of life. Recently, stem cell therapy has been introduced as a promising alternative treatment for IC in animal models. We aimed to verify the efficacy and safety of the human perirenal adipose tissue-derived stromal vascular fraction (SVF) in an IC rat model.

METHODS

From eight-week-old female rats, an IC rat model was established by subcutaneous injection of 200 μg of uroplakin3A. The SVF was injected into the bladder submucosal layer of IC rats, and pain scale analysis, awakening cytometry, and histological and gene analyses of the bladder were performed. For the in vivo safety analysis, genomic DNA purification and histological analysis were also performed to check tumorigenicity and thrombus formation.

RESULTS

The mean pain scores in the SVF 20 μl group were significantly lower on days 7 and 14 than those in the control group, and bladder intercontraction intervals were significantly improved in the SVF groups in a dose-dependent manner. Regeneration of the bladder epithelium, basement membrane, and lamina propria was observed in the SVF group. In the SVF groups, however, bladder fibrosis and the expression of inflammatory markers were not significantly improved compared to those in the control group.

CONCLUSION

This study demonstrated that a perirenal adipose tissue-derived SVF is a promising alternative for the management of IC in terms of improving bladder pain and overactivity.

Application of antibody-conjugated small intestine submucosa to capture urine-derived stem cells for bladder repair in a rabbit model

The need for bladder reconstruction and side effects of cystoplasty have spawned the demand for the development of alternative material substitutes. Biomaterials such as submucosa of small intestine (SIS) have been widely used as patches for bladder repair, but the outcomes are not fully satisfactory. To capture stem cells in situ has been considered as a promising strategy to speed up the process of re-cellularization and functionalization. In this study, we have developed an anti-CD29 antibody-conjugated SIS scaffold (AC-SIS) which is capable of specifically capturing urine-derived stem cells (USCs) in situ for tissue repair and regeneration. The scaffold has exhibited effective capture capacity and sound biocompatibility. In vivo experiment proved that the AC-SIS scaffold could promote rapid endothelium healing and smooth muscle regeneration. The endogenous stem cell capturing scaffolds has thereby provided a new revenue for developing effective and safer bladder patches.

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We developed an anti-CD29 antibody-crosslinked submucosa of small intestine scaffold (AC-SIS).

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AC-SIS is capable of specifically capturing urine-derived stem cells (USCs) as well as possesses a sound biocompatibility.

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AC-SIS promotes in situ tissue regeneration by facilitating the repair of bladder epithelium, smooth muscle and angiogenesis.

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Design and application of endogenous stem cell capturing scaffolds provides a new strategy for bladder repair.

Urine-Derived Stem Cells for Regenerative Medicine: Basic Biology, Applications, and Challenges

Regenerative medicine based on stem cell research has the potential to provide advanced health care for human beings. Recent studies demonstrate that stem cells in human urine can serve as an excellent source of graft cells for regenerative therapy, mainly due to simple, low-cost, and noninvasive cell isolation. These cells, termed human urine-derived stem cells (USCs), are highly expandable and can differentiate into various cell lineages. They share many biological properties with mesenchymal stem cells, such as potent paracrine effects and immunomodulation ability. The advantage of USCs has motivated researchers to explore their applications in regenerative medicine, including genitourinary regeneration, musculoskeletal repair, skin wound healing, and disease treatment. Although USCs have showed many positive outcomes in preclinical studies, and although the possible applications of USCs for animal therapy have been reported, many issues need to be addressed before clinical translation. This article provides a comprehensive review of USC biology and recent advances in their application for tissue regeneration. Challenges in the clinical translation of USC-based therapy are also discussed. Impact statement Recently, stem cells isolated from urine, referred to as urine-derived stem cells (USCs), have gained much interest in the field of regenerative medicine. Many advantages of human USCs have been found for cell-based therapy: (i) the cell isolation procedure is simple and low cost; (ii) they have remarkable proliferation ability, multidifferentiation potential, and paracrine effects; and (iii) they facilitate tissue regeneration in many animal models. With the hope to facilitate the development of USC-based therapy, we describe the current understanding of USC biology, summarize recent advances in their applications, and discuss future challenges in clinical translation.

Roles of mesenchymal stem cells and exosomes in interstitial cystitis/bladder pain syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is characterized by several symptoms of higher sensitivity of the lower urinary tract, such as bladder pain/discomfort, urgency, urinary frequency, pelvic pain and nocturia. Although the pathophysiology of IC/BPS is not fully understood, the hypothesis suggests that mast cell activation, glycosaminoglycan (GAG) layer defects, urothelium permeability disruption, inflammation, autoimmune disorder and infection are potential mechanisms. Mesenchymal stem cells (MSCs) have been proven to protect against tissue injury in IC/BPS by migrating into bladders, differentiating into key bladder cells, inhibiting mast cell accumulation and cellular apoptosis, inhibiting inflammation and oxidative stress, alleviating collagen fibre accumulation and enhancing tissue regeneration in bladder tissues. In addition, MSCs can protect against tissue injury in IC/BPS by secreting various soluble factors, including exosomes and other soluble factors, with antiapoptotic, anti-inflammatory, angiogenic and immunomodulatory properties in a cell-to-cell independent manner. In this review, we comprehensively summarized the current potential pathophysiological mechanisms and standard treatments of IC/BPS, and we discussed the potential mechanisms and therapeutic effects of MSCs and MSC-derived exosomes in alleviating tissue injury in IC/BPS models.

Possible role of intravenous administration of mesenchymal stem cells to alleviate interstitial cystitis/bladder pain syndrome in a Toll-like receptor-7 agonist-induced experimental animal model in rat

BACKGROUND

Interstitial cystitis/bladder pain syndrome (IC/BPS) categorized with and without Hunner lesions is a condition that displays chronic pelvic pain related to the bladder with no efficacious treatment options. There are strong associations suggested between Hunner-type IC and autoimmune diseases. Recently, we established an animal model of Hunner-type IC using a Toll-like receptor-7 (TLR7) agonist. Intravenous infusion of mesenchymal stem cells (MSCs) can be used to treat injury via multimodal and orchestrated therapeutic mechanisms including anti-inflammatory effects. Here, we investigated whether infused MSCs elicit therapeutic efficacy associated with the TLR7-related anti-inflammatory pathway in our Hunner-type IC model.

METHODS

Voiding behaviors were monitored 24 h prior to the Loxoribine (LX), which is a TLR7 agonist instillation in order to establish a Hunner-type IC model (from - 24 to 0 h) in female Sprague-Dawley rats. LX was instilled transurethrally into the bladder. At 0 h, the initial freezing behavior test confirmed that no freezing behavior was observed in any of the animals. The LX-instilled animals were randomized. Randomized LX-instilled rats were intravenously infused with MSCs or with vehicle through the right external jugular vein. Sampling tissue for green fluorescent protein (GFP)-positive MSCs were carried out at 48 h. Second voiding behavior tests were monitored from 72 to 96 h. After the final evaluation of the freezing behavior test at 96 h after LX instillation (72 h after MSC or vehicle infusion), histological evaluation with H&E staining and quantitative real-time polymerase chain reaction (RT-PCR) to analyze the mRNA expression levels of inflammatory cytokines were performed.

RESULTS

Freezing behavior was reduced in the MSC group, and voiding behavior in the MSC group did not deteriorate. Hematoxylin-eosin staining showed that mucosal edema, leukocyte infiltration, and hemorrhage were suppressed in the MSC group. The relative expression of interferon-β mRNA in the bladder of the MSC group was inhibited. Numerous GFP-positive MSCs were distributed mainly in the submucosal and mucosal layers of the inflammatory bladder wall.

CONCLUSION

Intravenous infusion of MSCs may have therapeutic efficacy in a LX-instilled Hunner-type IC rat model via a TLR7-related anti-inflammatory pathway.

A Systematic Review of Therapeutic Approaches Used in Experimental Models of Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a multifactorial, chronic bladder disorder with limited therapeutic options currently available. The present review provides an extensive overview of therapeutic approaches used in in vitro, ex vivo, and in vivo experimental models of IC/BPS. Publications were identified by electronic search of three online databases. Data were extracted for study design, type of treatment, main findings, and outcome, as well as for methodological quality and the reporting of measures to avoid bias. A total of 100 full-text articles were included. The majority of identified articles evaluated therapeutic agents currently recommended to treat IC/BPS by the American Urological Association guidelines (21%) and therapeutic agents currently approved to treat other diseases (11%). More recently published articles assessed therapeutic approaches using stem cells (11%) and plant-derived agents (10%), while novel potential drug targets identified were proteinase-activated (6%) and purinergic (4%) receptors, transient receptor potential channels (3%), microRNAs (2%), and activation of the cannabinoid system (7%). Our results show that the reported methodological quality of animal studies could be substantially improved, and measures to avoid bias should be more consistently reported in order to increase the value of preclinical research in IC/BPS for potential translation to a clinical setting.

Effect of amniotic fluid stem cell transplantation on the recovery of bladder dysfunction in spinal cord-injured rats

The effects of human amniotic fluid stem cell (hAFSC) transplantation on bladder function and molecular changes in spinal cord-injured (SCI) rats were investigated. Four groups were studied: sham and SCI plus phosphate-buffered saline (SCI + PBS), human embryonic kidney 293 (HEK293) cells, and hAFSCs transplantation. In SCI + PBS rat bladders, cystometry showed increased peak voiding pressure, voiding volume, bladder capacity, residual volume, and number of non-voiding contractions, and the total elastin/collagen amount was increased but collagen concentration was decreased at days 7 and 28. Immunoreactivity and mRNA levels of IGF-1, TGF-β1, and β3-adrenoceptor were increased at days 7 and/or 28. M2 immunoreactivity and M3 mRNA levels of muscarinic receptor were increased at day 7. M2 immunoreactivity was increased, but M2/M3 mRNA and M3 immunoreactivity levels were decreased at day 28. Brain derived-neurotrophic factor mRNA was increased, but immunoreactivity was decreased at day 7. HEK293 cell transplantation caused no difference compared to SCI + PBS group. hAFSCs co-localized with neural cell markers and expressed BDNF, TGF-β1, GFAP, and IL-6. The present results showed that SCI bladders released IGF-1 and TGF-β1 to stimulate elastin and collagen for bladder wall remodelling, and hAFSC transplantation improved these changes, which involved the mechanisms of BDNF, muscarinic receptors, and β3-adrenoceptor expression.

Application of Adult and Pluripotent Stem Cells in Interstitial Cystitis/Bladder Pain Syndrome Therapy: Methods and Perspectives

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a multifactorial, chronic disease without definite etiology characterized by bladder-related pelvic pain. IC/BPS is associated with pain that negatively affects the quality of life. There are various therapeutic approaches against IC/BPS. However, no efficient therapeutic agent against IC/BPS has been discovered yet. Urothelium dysfunction is one of the key factors of IC/BPS-related pathogenicity. Stem cells, including adult stem cells (ASCs) and pluripotent stem cells (PSCs), such as embryonic stem cells (ESCs) and induced PSCs (iPSCs), possess the abilities of self-renewal, proliferation, and differentiation into various cell types, including urothelial and other bladder cells. Therefore, stem cells are considered robust candidates for bladder regeneration. This review provides a brief overview of the etiology, pathophysiology, diagnosis, and treatment of IC/BPS as well as a summary of ASCs and PSCs. The potential of ASCs and PSCs in bladder regeneration via differentiation into bladder cells or direct transplantation into the bladder and the possible applications in IC/BPS therapy are described in detail. A better understanding of current studies on stem cells and bladder regeneration will allow further improvement in the approaches of stem cell applications for highly efficient IC/BPS therapy.