Changes in urine levels of substance P, vasoactive intestinal peptide and calcitonin-gene-related peptide in patients with urinary tract infections

Therapeutic Effects of IL-1RA against Acute Bacterial Infections, including Antibiotic-Resistant Strains

Innate immunity is essential for the anti-microbial defense, but excessive immune activation may cause severe disease. In this study, immunotherapy was shown to prevent excessive innate immune activation and restore the anti-bacterial defense. E. coli-infected Asc-/- mice develop severe acute cystitis, defined by IL-1 hyper-activation, high bacterial counts, and extensive tissue pathology. Here, the interleukin-1 receptor antagonist (IL-1RA), which inhibits IL-1 hyper-activation in acute cystitis, was identified as a more potent inhibitor of inflammation and NK1R- and substance P-dependent pain than cefotaxime. Furthermore, IL-1RA treatment inhibited the excessive innate immune activation in the kidneys of infected Irf3-/- mice and restored tissue integrity. Unexpectedly, IL-1RA also accelerated bacterial clearance from infected bladders and kidneys, including antibiotic-resistant E. coli, where cefotaxime treatment was inefficient. The results suggest that by targeting the IL-1 response, control of the innate immune response to infection may be regained, with highly favorable treatment outcomes, including infections caused by antibiotic-resistant strains.

Neuroepithelial control of mucosal inflammation in acute cystitis

The nervous system is engaged by infection, indirectly through inflammatory cascades or directly, by bacterial attack on nerve cells. Here we identify a neuro-epithelial activation loop that participates in the control of mucosal inflammation and pain in acute cystitis. We show that infection activates Neurokinin-1 receptor (NK1R) and Substance P (SP) expression in nerve cells and bladder epithelial cells in vitro and in vivo in the urinary bladder mucosa. Specific innate immune response genes regulated this mucosal response, and single gene deletions resulted either in protection (Tlr4^−/− and Il1b^−/− mice) or in accentuated bladder pathology (Asc^−/− and Nlrp3^−/− mice), compared to controls. NK1R/SP expression was lower in Tlr4^−/− and Il1b^−/− mice than in C56BL/6WT controls but in Asc^−/− and Nlrp3^−/− mice, NK1R over-activation accompanied the exaggerated disease phenotype, due, in part to transcriptional de-repression of Tacr1. Pharmacologic NK1R inhibitors attenuated acute cystitis in susceptible mice, supporting a role in disease pathogenesis. Clinical relevance was suggested by elevated urine SP levels in patients with acute cystitis, compared to patients with asymptomatic bacteriuria identifying NK1R/SP as potential therapeutic targets. We propose that NK1R and SP influence the severity of acute cystitis through a neuro-epithelial activation loop that controls pain and mucosal inflammation.

Activation of neuroimmune pathways increases therapeutic effects of radiotherapy on poorly differentiated breast carcinoma

Recent studies document the importance of neuronal dysfunction in cancer development and metastasis. We reported previously that both depletion of neuropeptides in capsaicin-sensitive sensory nerve endings and vagotomy increases metastasis of triple negative breast carcinoma. Of the sensory neuropeptides, Substance P (SP) is distributed widely for regulation of immune functions. We therefore examined the affects of continuous exposure to low doses of SP on brain metastatic cells of the mouse breast carcinoma (4TBM) in the presence of radiotherapy (RT) thought to increase antigenicity of cancer cells. 4TBM cells have a cancer stem cell phenotype and induce extensive visceral metastasis after orthotopic inoculation into the mammary pad. Results demonstrated that SP treatment decreases the number of tumor-infiltrating myeloid-derived suppressor cells as well as the TNF-α response to LPS challenge. SP also increased CD4+Cd25(bright) cells in draining lymph nodes of tumor-bearing animals and IFN-γ secretion from leukocyte culture prepared from lymph nodes and spleens of tumor-bearing animals. SP also prevented tumor-induced degeneration of sensory nerve endings and altered release of angiogenic factors from cancer-associated fibroblasts (CAF) and tumor explants. In accordance with these observed immunological effects, combination treatment of continuous SP with a single dose of RT induced complete tumor regression and significantly reduced or prevented metastasis in 50% of the animals while suppressing primary tumor growth and metastasis in the remaining mice. These original findings demonstrate that SP through neuroimmune modulation can prevent formation of immune suppression in the tumor microenvironment, enhance cytotoxic immunity in the presence of RT and prevent metastatic growth.

Management of Catheter-Related Bladder Discomfort in Patients Who Underwent Elective Surgery

OBJECTIVE

Despite the various treatment and prevention options for catheter-related bladder discomfort (CRBD), many uncertainties persist in clinical practice. To systematically review the literature on the management of CRBD in patients who underwent surgery.

MATERIALS AND METHODS

Eligible, randomized controlled trials were identified from electronic databases (Cochrane Central Register of Controlled Trials, Medline, and EMBASE) without language restrictions. Selection criteria, methodological rigor, and risk of bias were evaluated by two independent reviewers using Cochrane Collaboration's tools.

RESULTS

A total of 1441 patients from 14 articles published between 2005 and 2014 were included. Data heterogeneity precluded meta-analysis; therefore, data were synthesized narratively. Compared with nonurological surgery, CRBD is frequent and occurred immediately after urological surgery, especially after transurethral resection of the bladder tumor (TURBT). Data from included studies suggested that muscarinic antagonists, anesthetics, antiepileptics, and analgesics were associated with significant improvement in symptoms and reducing the incidence of CRBD, compared with placebo. Anticholinergic agents and antiepileptics (gabapentin and pregabalin) administered 1 hour before surgery reduced the incidence and severity of CRBD in the immediate postoperative period. Tramadol and ketamine are centrally acting opioid analgesics with antimuscarinic actions, which effectively prevent CRBD when administered intravenously. Paracetamol administered was also effective for the management of CRBD. Additionally, we perceived that TURBT is the surgical procedure that is the most refractory to treatment.

CONCLUSIONS

Muscarinic antagonists, anesthetics, antiepileptics, and paracetamol appear to achieve the greatest improvement in the clinical symptoms and a significant reduction in the incidence of CRBD compared with placebo. Although these studies observed a high incidence of intervention-related side effects, in general, patients tolerated these treatments well.