Oxybutynin and propiverine suppress adenosine triphosphate-induced bladder overactivity other than through antimuscarinic mechanisms

Network Medicine-Based Strategy Identifies Maprotiline as a Repurposable Drug by Inhibiting PD-L1 Expression via Targeting SPOP in Cancer

Immune checkpoint inhibitors (ICIs) are drugs that inhibit immune checkpoint (ICP) molecules to restore the antitumor activity of immune cells and eliminate tumor cells. Due to the limitations and certain side effects of current ICIs, such as programmed death protein-1, programmed cell death-ligand 1, and cytotoxic T lymphocyte-associated antigen 4 (CTLA4) antibodies, there is an urgent need to find new drugs with ICP inhibitory effects. In this study, a network-based computational framework called multi-network algorithm-driven drug repositioning targeting ICP (Mnet-DRI) is developed to accurately repurpose novel ICIs from ≈3000 Food and Drug Administration-approved or investigational drugs. By applying Mnet-DRI to PD-L1, maprotiline (MAP), an antidepressant drug is repurposed, as a potential PD-L1 modifier for colorectal and lung cancers. Experimental validation revealed that MAP reduced PD-L1 expression by targeting E3 ubiquitin ligase speckle-type zinc finger structural protein (SPOP), and the combination of MAP and anti-CTLA4 in vivo significantly enhanced the antitumor effect, providing a new alternative for the clinical treatment of colorectal and lung cancer.

Pharmacotherapy in overactive bladder

Overactive bladder syndrome (OAB) has a high prevalence within the population and has a negative effect on quality of life. Although the precise pathophysiology has yet to be fully elucidated, pharmacotherapeutic agents have been developed targeting two main pathways, antimuscarinic drugs and β3-adrenoreceptor agonists. Conservative management strategies, for example, bladder training, should be used as first-line treatment, with pharmacotherapy used as an adjunct if this is insufficiently effective. Antimuscarinics have a moderate effect on treating the symptoms of OAB, are associated with side effects, particularly dry mouth, and have low adherence rates in the long term. No single agent has consistently shown superiority over another. Antimuscarinics can affect cognition and may contribute to the anticholinergic burden in elderly patients. Mirabegron, a β3-agonist, appears to be as effective as antimuscarinics in improving symptoms of OAB with fewer side effects and improved adherence, and is currently recommended if treatment with antimuscarinics has failed. A combination of an antimuscarinic and β3-agonist may be worth considering if symptoms remain refractory or to reduce the side-effect profile associated with higher doses of antimuscarinics.

Level of evidence: Not applicable.

Animal models of gastrointestinal and liver diseases. Animal models of visceral pain: pathophysiology, translational relevance, and challenges

Visceral pain describes pain emanating from the thoracic, pelvic, or abdominal organs. In contrast to somatic pain, visceral pain is generally vague, poorly localized, and characterized by hypersensitivity to a stimulus such as organ distension. Animal models have played a pivotal role in our understanding of the mechanisms underlying the pathophysiology of visceral pain. This review focuses on animal models of visceral pain and their translational relevance. In addition, the challenges of using animal models to develop novel therapeutic approaches to treat visceral pain will be discussed.

Chronic psychological stress in high-anxiety rats induces sustained bladder hyperalgesia

OBJECTIVE

To evaluate whether anxiety-prone rats exposed to chronic water avoidance stress (WAS) develop visceral bladder hyperalgesia in addition to increased voiding frequency and anxiety-related behaviors.

MATERIALS AND METHODS

Female Wistar-Kyoto (WKY) rats were exposed to chronic (10-day) WAS or sham paradigms. Referred hyperalgesia and tactile allodynia were tested using von Frey filaments applied to the suprapubic region and plantar region of the hindpaw, respectively. To confirm that suprapubic nociception represented referred visceral bladder hyperalgesia, we recorded abdominal visceromotor responses (VMR) to slow (100 μl/min) and fast (1 cc/sec) bladder filling with room temperature or ice-cold saline. We assessed the development of hyperalgesia over the 10-day WAS protocol and the durability of increased pain sensations over time.

RESULTS

Animals exposed to chronic WAS had significantly lower hindpaw withdrawal thresholds post-stress and significant differences in referred hyperalgesia. Rats exposed to chronic WAS demonstrated an increased pain response to suprapubic stimulation and decreased response threshold to mechanical hindpaw stimulation by day 8 of the stress protocol, which persisted for more than one month. Animals exposed to chronic WAS showed increased VMR to fast filling and ice water testing in comparison to sham animals. Cystometry under anesthesia did not show increases in the frequency of non-voiding contractions.

CONCLUSION

Chronic WAS induces sustained bladder hyperalgesia, lasting over a month after exposure to stress. The urinary frequency demonstrated previously in anxiety-prone rats exposed to chronic WAS seems to be associated with bladder hyperalgesia, suggesting that this is a potential model for future studies of bladder hypersensitivity syndromes such as interstitial cystitis/painful bladder syndrome (IC/PBS).

Propiverine: a review of its use in the treatment of adults and children with overactive bladder associated with idiopathic or neurogenic detrusor overactivity, and in men with lower urinary tract symptoms

Propiverine is a well established antimuscarinic agent with a mixed mode of action in the treatment of symptoms associated with overactive bladder (OAB). As well as blocking muscarinic receptors in the detrusor muscle, the drug also inhibits cellular calcium influx, thereby diminishing muscle spasm. In patients with symptoms of OAB resulting from idiopathic detrusor overactivity (IDO) or neurogenic detrusor overactivity (NDO), propiverine demonstrated dose-dependent efficacy and tolerability, with adverse events consistent with those associated with all antimuscarinic agents. In adults with IDO, propiverine demonstrated similar efficacy to that of other antimuscarinic agents (including solifenacin, tolterodine, oxybutynin and imidafenacin) and, in adults with NDO, propiverine and oxybutynin demonstrated similar efficacy. Propiverine was generally well tolerated in these patient populations, with a lower incidence of dry mouth than that associated with oxybutynin. In men with lower urinary tract symptoms (LUTS), and in whom the presence of benign prostatic enlargement (BPE) was implicated, propiverine administered as add-on therapy to an α(1)-adrenoceptor antagonist demonstrated similar or superior efficacy to that achieved with an α(1)-adrenoceptor antagonist alone, and combination therapy was particularly effective in patients with urinary storage symptoms. Combination therapy was generally well tolerated, but was associated with a higher incidence of adverse events than an α(1)-adrenoceptor antagonist alone. In children and adolescents with IDO/OAB or NDO, propiverine was generally more effective and better tolerated than oxybutynin. In conclusion, propiverine provides a valuable option for the treatment of adults and children with OAB associated with IDO or NDO, and in men with storage LUTS.