Intravesical injections of autologous platelet-rich plasma for the treatment of refractory interstitial cystitis

The urothelium acts as a barrier for the urinary bladder that prevents the influx of urinary toxic substances, electrolytes, urea nitrogen, and pathogens into the circulation. Acute or chronic inflammation of the urinary bladder may impair the regenerative function of urothelial cells and thus urothelial cell differentiation. In an inflamed bladder wall, mature apical cells are defective, resulting in impaired barrier function and thus increased urothelial permeability. This is considered to be the potential mechanism of the symptom trigger in patients with interstitial cystitis/bladder pain syndrome (IC/BPS). Previous studies have revealed that increased bladder inflammation, impaired urothelial cell maturation, a defective umbrella cell barrier, and defective junction proteins are prominent in IC/BPS bladders. Platelet-rich plasma (PRP) contains many growth factors and cytokines that are essential proteins for modulating inflammation and promoting tissue regeneration and thus wound healing. As such, PRP has been used as a regenerative therapy in many medical fields. Our preliminary studies have demonstrated that multiple intravesical PRP injections could improve symptoms in 70% of IC/BPS patients. Repeated PRP treatments also improve junctional protein, increase cytoskeleton protein expression, and decrease urinary inflammatory proteins. These preliminary results suggest that PRP injections might reduce bladder inflammation and improve urothelial cell regeneration in IC/BPS patients. This article reviews recently published clinical and basic research on the treatment potential of PRP for IC/BPS patients.

Platelet-Rich Plasma Ameliorates Cyclophosphamide-Induced Acute Interstitial Cystitis/Painful Bladder Syndrome in a Rat Model

Background: Interstitial cystitis/painful bladder syndrome (IC/PBS) could be treated to ameliorate urothelial injury. Here, we investigated the efficacy of intravesical instillation with platelet-rich plasma (PRP) and hyaluronic acid for acute IC/PBS. Methods: The effects of PRP and hyaluronic acid on the proliferation of normal human fibroblast cells (HFCs) were assessed. Additionally, thirty virgin female rats were randomized into five groups: group 1, saline-injected control; group 2, cyclophosphamide (CYP) plus intravesical instillation with normal saline; group 3, CYP plus intravesical instillation with hyaluronic acid (1 mg/mL); group 4, CYP plus intravesical instillation with PRP; and group 5, CYP plus intravesical instillation with PRP plus hyaluronic acid. A cystometry and histological assessments were performed. The expression of cell junction-associated protein zonula occludens-2 (ZO-2) and inflammatory cytokine interleukin 6 (IL-6) was also measured. Results: Low dose PRP increased proliferation in HFCs. The acute IC/PBS rats showed significantly lower voiding interval values. Voiding interval values were significantly higher in the CYP plus intravesical instillation with PRP group than in the CYP-induced acute IC/PBS group. Additionally, the expression of ZO-2 was increased and IL-6 was decreased in the CYP plus intravesical instillation with PRP group compared with the CYP-induced acute IC/PBS group. Conclusion: These findings suggest that PRP modulate urothelial repair, which ameliorate the increase in urination frequency in rats treated with CYP. Overall, PRP may confer potential benefits by acting as urothelial repair modulators.

IPSE, a urogenital parasite-derived immunomodulatory protein, ameliorates ifosfamide-induced hemorrhagic cystitis through downregulation of pro-inflammatory pathways

Ifosfamide and other oxazaphosphorines can result in hemorrhagic cystitis, a constellation of complications caused by acrolein metabolites. We previously showed that a single dose of IPSE (Interleukin-4-inducing principle from Schistosoma eggs), a schistosome-derived host modulatory protein, can ameliorate ifosfamide-related cystitis; however, the mechanisms underlying this urotoxicity and its prevention are not fully understood. To provide insights into IPSE’s protective mechanism, we undertook transcriptional profiling of bladders from ifosfamide-treated mice, with or without pretreatment with IPSE or IPSE-NLS (a mutant of IPSE lacking nuclear localization sequence). Ifosfamide treatment upregulated a range of proinflammatory genes. The IL-1β-TNFα-IL-6 proinflammatory cascade via NFκB and STAT3 pathways was identified as the key driver of inflammation. The NRF2-mediated oxidative stress response pathway, which regulates heme homoeostasis and expression of antioxidant enzymes, was highly activated. Anti-inflammatory cascades, namely Wnt, Hedgehog and PPAR pathways, were downregulated. IPSE drove significant downregulation of major proinflammatory pathways including the IL-1β-TNFα-IL-6 pathways, interferon signaling, and reduction in oxidative stress. IPSE-NLS reduced inflammation but not oxidative stress. Taken together, we have identified signatures of acute-phase inflammation and oxidative stress in ifosfamide-injured bladder, which are reversed by pretreatment with IPSE. This work revealed several pathways that could be therapeutically targeted to prevent ifosfamide-induced hemorrhagic cystitis.

Repeated intravesical injections of platelet-rich plasma are effective in the treatment of interstitial cystitis: a case control pilot study

OBJECTIVE

Interstitial cystitis (IC), also known as bladder pain syndrome (BPS), is a debilitating chronic disease. There are few treatment options for IC/BPS refractory to current medical therapy. This study investigated the clinical efficacy of intravesical injections of platelet-rich plasma (PRP) in IC/BPS.

METHODS

Fifteen patients with IC/BPS received 4 intravesical injections, at 1-monthly intervals, of 12 mL PRP extracted from 50 mL of the patient's whole blood, followed by cystoscopic hydrodistention. The primary endpoint was the change in O'Leary-Sant symptom (OSS) index from baseline to 1 month after the 4th PRP injection. Secondary endpoints were changes in pain (measured using a visual analog scale [VAS]), daily frequency, nocturia, functional bladder capacity (FBC), maximum flow rate, voided volume, post-void residual (PVR) volume, and global response assessment (GRA). Urinary cytokine levels were measured at baseline and 1 month after the 1st PRP treatment.

RESULTS

Of the 15 women in the study, 13 completed the 4 injections and follow-up visits (mean [± SD] age 52.9 ± 12.1 years). The OSS index and VAS pain score decreased significantly and FBC and GRA increased after the 1st PRP injection and lasted until the final endpoint. There was no change in PVR after repeated PRP injections, and all patients were free of urinary tract infections and difficulty urinating. Urinary interleukin (IL)-2 and IL-8 concentrations increased significantly after the 1st PRP injection. In patients with reductions in the VAS pain score ≥1, urinary IL-8 and vascular endothelial growth factor increased. In patients without reductions in the VAS pain score, IL-6 concentrations increased after PRP injection.

CONCLUSIONS

Repeated intravesical PRP injections are well tolerated and appear to be safe and effective in medically refractive IC/BPS, providing significant symptom improvement.