Botulinum toxin in the treatment of OAB, BPH, and IC

Efficacy of Clorpactin in refractory bladder pain syndrome/interstitial cystitis: a randomized controlled trial

INTRODUCTION

Clorpactin is an antibacterial agent with limited evidence for its use as instillation therapy in patients with bladder pain syndrome/interstitial cystitis (BPS/IC). This was a multi-centre, single-blinded randomized controlled trial to investigate whether Clorpactin instillation results in symptom improvement in patients with refractory BPS/IC.

METHODS

Fifty women with refractory BPS/IC were randomized to undergo cystoscopy/hydrodistension (25) or instillation of Clorpactin 0.4% solution (25) under general anaesthesia. Primary outcome was based on Global Response Assessment (GRA) at 3 months; secondary outcomes were based on O'Leary Sant Symptom (OLSI) and Problem (OLPI) questionnaire scores, visual analogue scale (VAS) score for pain and bladder diary parameters.

RESULTS

Complete follow-up data were available on 22 in the hydrodistension group and 16 in the Clorpactin group. GRA improvement was 4.5% for hydrodistension and 56% for Clorpactin (p = 0.001) at 3 months. Reduction in mean total scores for OLSI (14.1 to 9.1; p = 0.004) and OLPI (12.6 to 7.4; p = 0.001) was seen in the Clorpactin group only. VAS pain scores were reduced in the Clorpactin group only (7.4 to 3.3; p < 0.001). Post-treatment VAS pain scores did not differ between groups although 6/25 (24%) women in the Clorpactin group required admission for pain compared to 1/25 (4%) in the hydrodistension group.

CONCLUSIONS

Clorpactin treatment results in significant improvement in BPS/IC symptoms, bother and pain based on the GRA, OLSI/OLPI and VAS pain scores at 3 months post-treatment compared to cystoscopy/hydrodistension. These conclusions are limited by the high loss to follow-up in both groups.

Toxin-induced hormesis may restrain aging

Mild environmental stress might have beneficial effects in aging by activating maintenance and repair processes in cells and organs. These beneficial stress effects fit to the concept of hormesis. Prominent stressors acting in a hormetic way are physical exercises, fasting, cold and heat. This review will introduce some toxins, which have been found to induce hormetic responses in animal models of aging research. To highlight the molecular signature of these hormetic effects we will depict signaling pathways affected by low doses of toxins on cellular and organismic level. As prominent examples for signaling pathways involved in both aging processes as well as toxin responses, PI3K/Akt/mTOR- and AMPK-signal transduction will be described in more detail. Due to the striking overlap of signaling pathways mediating toxin induced responses and aging processes we propose considering the ability of low doses of toxins to slow down the rate of aging.

Urinary Biomarkers in Women with Refractory Urgency Urinary Incontinence Randomized to Sacral Neuromodulation versus OnabotulinumtoxinA Compared to Controls

PURPOSE

We measured urinary biomarker levels in women with refractory urgency urinary incontinence and controls at baseline and 6 months after treatment with sacral neuromodulation or intradetrusor injection of onabotulinumtoxinA. We also assessed the association of baseline biomarkers with posttreatment urgency urinary incontinence episodes and overactive bladder symptom bother outcomes.

MATERIALS AND METHODS

First morning urine samples were collected from consented trial participants and age matched women without urgency urinary incontinence. Biomarkers reflecting general inflammation, neuroinflammation, afferent neurotransmitters and tissue remodeling were measured using standardized enzyme-linked immunosorbent assay and activity assays as appropriate. Symptom bother was assessed by the overactive bladder questionnaire and urgency urinary incontinence episodes were determined by bladder diary. Linear models were used to examine differences in mean biomarker levels and the change in urgency urinary incontinence episodes and symptom bother between baseline and 6 months. Modest evidence of a potential association was represented by p ≤0.01 and p ≤0.004 represented moderate evidence of an association with outcomes.

RESULTS

Baseline biomarker levels differed little between cases and controls except tropoelastin (p = 0.001) and N-terminal telopeptide collagen type 1 (p <0.001). Changes in biomarker levels 6 months after intervention included decreases in collagenase (p <0.001) in both treatment groups and increases in interleukin-8 (p = 0.002) and matrix metalloprotease-9 (p <0.001) in the onabotulinumtoxinA group. Higher baseline calcitonin gene-related peptide across both treatments (p = 0.007) and nerve growth factor in the onabotulinumtoxinA arm (p = 0.007) were associated with less reduction in overactive bladder symptom bother.

CONCLUSIONS

Refractory urgency urinary incontinence is a complex condition. These data suggest that matrix remodeling and neuropeptide mediation may be involved in its pathophysiological mechanisms and response to treatment.

Preclinical assessment of potential interactions between botulinum toxin and neuromodulation for bladder micturition reflex

BACKGROUND

While botulinum toxin A (BoNT-A) has become a more commonly used second-line treatment for patients with detrusor overactivity, it remains unknown whether the impacts of this therapy may persist to influence other therapies such as sacral neuromodulation. In this preclinical study we have evaluated urodynamic functions to intradetrusor injection of BoNT-A and the bladder inhibitory effects of spinal nerve stimulation (SNS) following BoNT-A treatment.

METHODS

Female rats were anesthetized with 3 % isoflurane. BoNT-A (2 units, 0.2 ml) or saline were injected into the detrusor. Rats then were housed for 2 days to 1 month before neuromodulation study. Monopolar electrodes were placed under each of the L6 spinal nerve bilaterally under urethane anesthesia. A bladder cannula was inserted via the urethra for saline infusion and intravesical pressure recording.

RESULTS

Intradetrusor injection of BoNT-A for 1-2 weeks or 1 month significantly increased bladder capacity compared with saline injection (p < 0.05, two-way ANOVA). Following BoNT-A, SNS attenuated the frequency of bladder contractions, either eliminating bladder contractions or reducing the contraction frequency during electrical stimulation. Inhibition of the contraction frequency by SNS following BoNT-A treated rats was not different from that measured following saline injection.

CONCLUSIONS

BoNT-A increased the bladder capacity, but compensating for additional saline infusion to the enlarged urinary bladder in BoNT-A pretreated rats, the bladder contractions induced by bladder filling were attenuated by SNS. BoNT-A did not alter the ability of SNS to inhibit bladder contraction following intradetrusor injection of BoNT-A for 2 days, 1-2 weeks or 1 month. These results support further pre-clinical and clinical studies to evaluate potential interactions or combination therapy with neuromodulation and intradetrusor BoNT-A therapeutic approaches.

Botulinum neurotoxin serotype A suppresses neurotransmitter release from afferent as well as efferent nerves in the urinary bladder

BACKGROUND

Botulinum neurotoxin A (BoNTA), which alleviates overactive bladder symptoms, is thought to act predominantly via the inhibition of transmitter release from parasympathetic nerves. However, actions at other sites such as afferent nerve terminals are possible.

OBJECTIVE

To evaluate the effects of BoNTA on bladder afferent neuropeptide release and firing.

DESIGN, SETTING, AND PARTICIPANTS

One side of the bladder of control and chronic (1-2 wk) spinal cord transected (SCT; T(8)-T(9)) adult female mice was injected with BoNTA (0.5 U/5 μl saline). After 48 h, bladders with L(6)-S(2) spinal nerves were prepared for in vitro recordings.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

In bladder preparations, tension and optical mapping of Ca(2+) transients were used to measure intrinsic contractions, those evoked by capsaicin or the electrical stimulation of spinal nerves. Afferent firing was evoked by stretch or intrinsic bladder contractions. The numbers of responding units and firing rates were measured. Animal numbers were used to detect moderate to large between-group differences based on Cohen's criteria. Two-way analysis of variance was used to test spatial/temporal differences in Ca(2+) signals as mean plus or minus standard deviation. Differences between data sets were tested with the student t test and skewed data sets with a Mann-Whitney U test (significant when p<0.05).

RESULTS AND LIMITATIONS

In control and SCT bladders, BoNTA treatment decreased the contractions evoked by electrical stimulation of spinal nerves without altering intrinsic contractions. Afferent firing on untreated sides in response to stretch/intrinsic contractions was increased in SCTs versus controls. On BoNTA-treated sides, afferent firing rates were greatly attenuated in response to mechanical stimulation as were the capsaicin-evoked optical signals mediated by neuropeptide release.

CONCLUSIONS

SCT caused an increased sensitivity of afferent nerves to mechanical stimulation that was reduced by BoNTA treatment. Increased intrinsic activity after SCT was unaffected by the toxin. Thus BoNTA suppresses neurogenic detrusor overactivity by targeting afferent as well as efferent pathways in the bladder.

Various treatment options for benign prostatic hyperplasia: A current update

In benign prostatic hyperplasia (BPH) there will be a sudden impact on overall quality of life of patient. This disease occurs normally at the age of 40 or above and also is associated with sexual dysfunction. Thus, there is a need of update on current medications of this disease. The presented review provides information on medications available for BPH. Phytotherapies with some improvements in BPH are also included. Relevant articles were identified through a search of the English-language literature indexed on MEDLINE, PUBMED, Sciencedirect and the proceedings of scientific meetings. The search terms were BPH, medications for BPH, drugs for BPH, combination therapies for BPH, Phytotherapies for BPH, Ayurveda and BPH, BPH treatments in Ayurveda. Medications including watchful waitings, Alpha one adrenoreceptor blockers, 5-alpha reductase inhibitors, combination therapies including tamsulosin-dutasteride, doxazosin-finasteride, terazosin-finasteride, tolterodine-tamsulosin and rofecoxib-finasteride were found. Herbal remedies such as Cernilton, Saxifraga stolonifera, Zi-Shen Pill (ZSP), Orbignya speciosa, Phellodendron amurense, Ganoderma lucidum, Serenoa Repens, pumpkin extract and Lepidium meyenii (Red Maca) have some improvements on BPH are included. Other than these discussions on Ayurvedic medications, TURP and minimally invasive therapies (MITs) are also included. Recent advancements in terms of newly synthesized molecules are also discussed. Specific alpha one adrenoreceptor blockers such as tamsulosin and alfuzosin will remain preferred choice of urologists for symptom relief. Medications with combination therapies are still needs more investigation to establish as preference in initial stage for fast symptom relief reduced prostate growth and obviously reduce need for BPH-related surgery. Due to lack of proper evidence Phytotherapies are not gaining much advantage. MITs and TURP are expensive and are rarely supported by healthcare systems.

Content of botulinum neurotoxin in Botox®/Vistabel®, Dysport®/Azzalure®, and Xeomin®/Bocouture®

Background: Botulinum neurotoxin type A (BoNT/A) is the active substance in preparations used for the highly effective treatment of neurologic disorders such as cervical dystonia, blepharospasm, or spasticity, as well as other indications such as axillary and palmar hyperhidrosis, and urologic disorders.

Objective: To determine the amount of BoNT/A protein present in pharmaceutical preparations of Botox®, Dysport®, and Xeomin®, which are identical with Vistabel®, Azzalure®, and Bocouture®, respectively.

Methods: Rabbit and guinea pig antibodies raised against the 150kD BoNT/A neurotoxin purified from Clostridium botulinum type A, strain ATCC 3502 (‘Hall strain’), were used in a sensitive sandwich ELISA to determine the overall mean concentration of the 150kD neurotoxin present in four batches of Botox® (C2344C3, C2384C3, C2419, and C2385), two batches of Dysport® (678F and 689X) and three batches of Xeomin® (61111, 70604, and 81 208). The specific neurotoxin potency, defined as the potency or biologic activity (units) per mass of neurotoxin protein (ng), was calculated based on the overall mean concentration of BoNT/A neurotoxin.

Results: Overall, the mean concentration of BoNT/A neurotoxin in Botox® was 0.73 ng per 100 unit vial (coefficient of variation [CV] = 3.5%), 3.24 ng per 500 unit vial of Dysport®, corresponding to 0.65 ng in 100 units (CV = 11.4%), and 0.44 ng per 100 unit vial of Xeomin® (CV = 1.9%). The specific potency of the 150kD BoNT/A neurotoxin was calculated as 137 units/ng for Botox®, 154 units/ng Dysport®, and 227 units/ng Xeomin®.

Conclusions: The current study has shown that of the three products, Xeomin® contains the highest specific neurotoxin activity, followed by Dysport®, with Botox® having the lowest specific activity. This result suggests that Xeomin® contains only active neurotoxin in contrast with Botox®, which is likely to contain additional denatured/inactive neurotoxin.

Complexing proteins in botulinum toxin type A drugs: a help or a hindrance?

Botulinum toxin type A is a high molecular weight protein complex containing active neurotoxin and complexing proteins, the latter of which, it is believed, protect the neurotoxin when in the gastrointestinal tract, and may facilitate its absorption. Comparisons of conventional botulinum toxin type A drugs that include complexing proteins with the complexing protein-free formulation of Xeomin^® strongly suggest that complexing proteins do not affect diffusion of the active neurotoxin. Studies of Xeomin have also shown that complexing proteins do not enhance product stability in storage. However, complexing proteins may stimulate antibody development against botulinum toxin type A. Numerous observational studies have been published showing that some patients receiving conventional botulinum toxin may develop neutralizing antibodies, leading to antibody-induced therapy failure. Studies have shown that Xeomin is not associated with the development of neutralizing antibodies in animal models or in patients. In conclusion, complexing proteins do not contribute to the stability of botulinum toxin type A drugs and do not contribute to their therapeutic effects, but may be associated with a secondary nonresponse due to the development of neutralizing antibodies.

Intravesical drug delivery: Challenges, current status, opportunities and novel strategies

The urinary bladder has certain unique anatomical features which enable it to form an effective barrier to toxic substances diffusing from the urine into the blood. The barrier function is due to the epithelial surface of the urinary bladder, the urothelium, which has characteristic umbrella cells, joined by tight junctions and covered by impenetrable plaques, as well as an anti-adherent mucin layer. Diseases of the urinary bladder, such as bladder carcinomas and interstitial cystitis, cause acute damage to the bladder wall and cannot be effectively treated by systemic administration of drugs. Such conditions may benefit from intravesical drug delivery (IDD), which involves direct instillation of drug into the bladder via a catheter, to attain high local concentrations of the drug with minimal systemic effects. IDD however has its limitations, since the permeability of the urothelial layer is very low and instilled drug solutions become diluted with urine and get washed out of the bladder during voiding, necessitating repeated infusions of the drug. Permeation enhancers serve to overcome these problems to some extent by using electromotive force to enhance diffusion of the drug into the bladder wall or chemical molecules, such as chitosan, dimethylsulphoxide, to temporarily disrupt the tight packing of the urothelium. Nanotechnology can be integrated with IDD to devise drug-encapsulated nanoparticles that can greatly improve chemical interactions with the urothelium and enhance penetration of drugs into the bladder wall. Nanocarriers such as liposomes, gelatin nanoparticles, polymeric nanoparticles and magnetic particles, have been found to enhance local drug concentrations in the bladder as well as target diseased cells. Intravesical drug carriers can be further improved by using mucoadhesive biomaterials which are strongly adhered to the urothelial cell lining, thus preventing the carrier from being washed away during urine voiding. This increases the residence time of the drug at the target site and enables sustained delivery of the drug over a prolonged time span. Polymeric hydrogels, such as the temperature sensitive PEG-PLGA-PEG polymer, have been used to develop in situ gelling systems to deliver drugs into the bladder cavity. Recent advances and future prospects of biodegradable nanocarriers and in situ gels as drug delivery agents for intravesical drug delivery are reviewed in this paper.