Chao-Cheng Huang

Intraprostatic injection of botulinum toxin type- A relieves bladder outlet obstruction in human and induces prostate apoptosis in dogs

BackgroundWith the increasing interest with botulinum toxin – A (BTX-A) application in the lower urinary tract, we investigated the BTX-A effects on the canine prostate and also in men with bladder outlet obstruction (BOO) due to benign prostatic hyperplasia (BPH).MethodsTransperineal injection into the prostate using transrectal ultrasound (TRUS) was performed throughout the study. Saline with or without 100 U of BTX-A was injected into mongrel dogs prostate. One or 3 months later, the prostate was harvested for morphologic and apoptotic study. In addition, eight BPH patients refractory to α-blockers were treated with ultrasound guided intraprostatic injection of 200 U of BTX-A.ResultsIn the BTX-A treated dogs, atrophy and diffuse apoptosis was observed with H&E stain and TUNEL stain at 1 and 3 months. Clinically, the mean prostate volume, symptom score, and quality of life index were significantly reduced by 18.8%, 73.1%, and 61.5% respectively. Maximal flow rate significantly increased by 72.0%.ConclusionIntraprostatic BTX-A injection induces prostate apotosis in dogs and relieves BOO in humans. It is therefore a promising alternative treatment for refractory BOO due to BPH.

Urodynamic and Immunohistochemical Evaluation of Intravesical Botulinum Toxin A Delivery Using Liposomes

PURPOSE Botulinum toxin A (Allergan, Irvine, California) is a high molecular weight neurotoxin used to treat hypersensitive bladder by direct injection to pass the urothelial barrier. We investigated the feasibility of intravesical botulinum toxin A delivery using liposomes (Lipella Pharmaceuticals, Pittsburgh, Pennsylvania), which are phospholipid bilayered vesicles, and evaluated the urodynamic and immunohistochemical effect on acetic acid induced bladder hyperactivity in rats. MATERIALS AND METHODS Liposomes (1 ml), botulinum toxin A (20 U/1 ml saline) or botulinum toxin A encapsulated in liposomes (lipotoxin, that is 20 U botulinum toxin A plus 1 ml liposomes) was administered in the bladder and retained for 1 hour on day 1 after baseline cystometrogram. Continuous cystometrogram was performed on day 1 by filling the bladder with saline and on day 8 by filling the bladder with saline, followed by 0.3% acetic acid. The bladder was then harvested. Cystometrogram parameters, histology, SNAP25 and calcitonin gene-related peptide expression were measured by Western blotting or immunostaining. RESULTS The intercontraction interval was decreased 57.2% and 56.0% after intravesical acetic acid instillation in liposome and botulinum toxin A pretreated rats, respectively. However, rats that received lipotoxin showed a significantly decreased intercontraction interval response (21.1% decrease) to acetic acid instillation but without compromised voiding function. Also, lipotoxin pretreated rats had a better decrease in the inflammatory reaction and SNAP-25 expression, and increase in calcitonin gene-related peptide immunoreactivity than those in liposome or botulinum toxin A pretreated rats. CONCLUSIONS Intravesical lipotoxin administration cleaved SNAP-25, inhibited calcitonin gene-related peptide release from afferent nerve terminals and blocked the acetic acid induced hyperactive bladder. These results support liposomes as an efficient vehicle for delivering botulinum toxin A without injection.

Intraprostatic Botulinum Toxin A Injection Inhibits Cyclooxygenase-2 Expression and Suppresses Prostatic Pain on Capsaicin Induced Prostatitis Model in Rat

PURPOSE Cyclooxygenase-2 is a key enzyme in the conversion of arachidonic acid to prostaglandins, which are important mediators of inflammation and pain. We investigated the effect of intraprostatic botulinum toxin A administration on pain reaction and cyclooxygenase-2 expression in a capsaicin induced prostatitis model in rats. MATERIALS AND METHODS Adult male Sprague-Dawley rats were injected with vehicle or capsaicin (10 mM, 0.1 cc) into the prostate. The nociceptive effects of capsaicin were evaluated for 30 minutes using a behavior approach. The prostate and L6 spinal cord were then removed for histology and cyclooxygenase-2 expression using Western blotting or immunostaining. A second set of animals was injected with botulinum toxin A (5 to 20 U) into the prostate 1 week before intraprostatic injection of capsaicin. RESULTS Capsaicin induced increased pain behavior and inflammatory reaction. Botulinum toxin A 1 week before treatment dose dependently decreased inflammatory cell accumulation, cyclooxygenase-2 expression and prostatic pain. Botulinum toxin A (20 U) significantly decreased inflammatory cell accumulation, and cyclooxygenase-2 expression in the prostate, ventral horn and dorsal horn of the L6 spinal cord (93.5%, 89.4%, 90.5% and 77.5%, respectively). It decreased pain behavior for eye and locomotion scores (59.5% and 40.0%, respectively). CONCLUSIONS Intraprostatic capsaicin injection activates cyclooxygenase-2 expression in the prostate, and spinal sensory and motor neurons, and it induces prostatic pain. Botulinum toxin A pretreatment could inhibit capsaicin induced cyclooxygenase-2 expression from the peripheral organ to the L6 spinal cord and inhibit prostatic pain and inflammation. This finding suggests a potential clinical benefit of botulinum toxin A for the treatment of nonbacterial prostatitis.

Intravesical botulinum toxin A administration inhibits COX-2 and EP4 expression and suppresses bladder hyperactivity in cyclophosphamide-induced cystitis in rats.

BACKGROUND Cyclooxygenase 2 (COX-2) elevation and subsequent prostaglandin E(2) (PGE(2)) production play a major role in bladder inflammation and hyperactivity. EP4 receptor, a subtype of PGE(2) receptors, mediates tissue inflammation and hypersensitivity. OBJECTIVE To investigate the effect of intravesical botulinum toxin A (BoNT-A) on COX-2 and EP4 expression in cyclophosphamide (CYP)-induced cystitis in rats. DESIGN, SETTING, AND PARTICIPANTS Experimental (N=40) and control animals (N=20) were injected with CYP (75 mg/kg intraperitoneally) or saline on days 1, 4, and 7. BoNT-A (1 ml, 20 unit/ml) or saline were administered into the bladder and retained for 1 h on day 2. INTERVENTION Waking cystometrograms (CMGs) were performed. Bladder and L6 and S1 spinal cord were harvested on day 8. MEASUREMENTS CMG parameters, histology, and COX-2 and EP4 expression by immunostaining or western blotting were measured. RESULTS AND LIMITATIONS CYP induced increased bladder inflammatory reaction, bladder hyperactivity, and COX-2 and EP4 expression in the bladder and spinal cord. The CYP effects were suppressed by BoNT-A treatment. BoNT-A treatment decreased inflammatory reaction (56.5% decrease), COX-2 expression (77.8%, 61.7%, and 54.8% decrease for bladder, L6, and S1 spinal cord, respectively), EP4 expression (56.8%, 26.9%, and 84.2% decrease for bladder, L6, and S1 spinal cord, respectively), and suppressed bladder hyperactivity (intercontraction interval, 107% increase and contraction amplitude, 43% decrease). CONCLUSIONS CYP injection activated COX2 and EP4 expression in the bladder and spinal cord and induced bladder inflammation and hyperactivity, which effects were suppressed by BoNT-A treatment. These findings suggest a potential benefit of EP4-targeted pharmacotherapy and BoNT-A treatment for bladder inflammatory conditions.

Functional and Molecular Characterization of Hyposensitive Underactive Bladder Tissue and Urine in Streptozotocin-Induced Diabetic Rat

Background The functional and molecular alterations of nerve growth factor (NGF) and Prostaglandin E2 (PGE2) and its receptors were studied in bladder and urine in streptozotocin (STZ)-induced diabetic rats. Methodology/Principal Findings Diabetes mellitus was induced with a single dose of 45 mg/kg STZ Intraperitoneally (i.p) in female Sprague-Dawley rats. Continuous cystometrogram were performed on control rats and STZ treated rats at week 4 or 12 under urethane anesthesia. Bladder was then harvested for histology, expression of EP receptors and NGF by western blotting, PGE2 levels by ELISA, and detection of apoptosis by TUNEL staining. In addition, 4-hr urine was collected from all groups for urine levels of PGE2, and NGF assay. DM induced progressive increase of bladder weight, urine production, intercontraction interval (ICI) and residual urine in a time dependent fashion. Upregulation of Prostaglandin E receptor (EP)1 and EP3 receptors and downregulation of NGF expression, increase in urine NGF and decrease levels of urine PGE2 at week 12 was observed. The decrease in ICI by intravesical instillation of PGE2 was by 51% in control rats and 31.4% in DM group at week 12. Conclusions/Significance DM induced hyposensitive underactive bladder which is characterized by increased inflammatory reaction, apoptosis, urine NGF levels, upregulation of EP1 and EP3 receptors and decreased bladder NGF and urine PGE2. The data suggest that EP3 receptor are potential targets in the treatment of diabetes induced underactive bladder.

Expression of E‐series prostaglandin (EP) receptors and urodynamic effects of an EP4 receptor antagonist on cyclophosphamide‐induced overactive bladder in rats

To investigate the expression of four subtypes of E‐series prostaglandin (EP1–EP4) receptors and the urodynamic effects of an EP4 receptor antagonist (AH23848) in cyclophosphamide (CYP)‐induced overactive bladder (OAB) in rats, as intravesical prostaglandin E2 (PGE2) induces OAB via activation of EP receptors and sensitization of afferent nerves.

Mechanisms and urodynamic effects of a potent and selective EP4 receptor antagonist, MF191, on cyclophosphamide and prostaglandin E2-induced bladder overactivity in rats.

Study Type – Aetiology (case control)

Pharmacologic and Molecular Characterization of Underactive Bladder Induced by Lumbar Canal Stenosis

OBJECTIVE To investigate the voiding function in a rat model of lumbar canal stenosis (LCS) using pharmacologic and molecular approaches. METHODS Sixty-one female Sprague-Dawley rats were broadly split into a sham and an LCS group. A hole was surgically drilled in the L5-L6 epidural space and filled with a rectangular piece of silicone rubber. Metabolic cage study at week 2 and continuous cystometry (CMG) under urethane anesthesia at weeks 2 and 4 were performed. During CMG, prostaglandin E2 or sulprostone, an prostaglandin E receptor 1 and prostaglandin E receptor 3 agonist was administered locally and intravenously, respectively, and the bladder was then harvested for histology and Western blot. RESULTS Compared with sham, the LCS group showed dribbling urination and progressive increase in bladder size. CMG under urethane anesthesia in the LCS group was marked by overflow incontinence and acontractile bladder. Administration of intravesical prostaglandin E2 (200 μM) or intravenous sulprostone (0.1 mg/kg) in the sham group induced bladder overactivity, but decreased the compliance and failed to restore the bladder emptying function in the LCS group. The LCS group showed edematous changes and muscle thinning at week 2, which were partially restored by week 4. Histologic changes were accompanied by downregulation of agrin protein (64.0%) at week 2 and upregulation of M2 receptor (65.4%) at week 4. Expression of M3, protein gene product 9.5, and nerve growth factor did not differ between groups. CONCLUSION LCS-induced underactive bladder is associated with altered expression of agrin and M2 receptor. The underactive bladder model is clinically relevant, and the findings indicate potential molecular targets for new therapies.

Effects of low energy shock wave therapy on inflammatory moleculars, bladder pain, and bladder function in a rat cystitis model.

Low energy shock wave (LESW) is known to facilitate tissue regeneration with analgesic and anti‐inflammatory effects. We examined the effects of LESW on the expression of inflammatory molecules, pain behavior, and bladder function in a rat cystitis model.

Urodynamic and molecular characteristics of detrusor underactivity in a rat cryoinjury model and effects of low energy shock wave therapy

Low energy shock wave (LESW) has been shown to facilitate tissue regeneration and reduce inflammation. We investigated the effects of LESW in an underactive (DU) model induced by cryoinjury of rat detrusor.