Dimethyl sulfoxide does not trigger urine histamine release in interstitial cystitis

Intravesical dimethyl sulfoxide inhibits acute and chronic bladder inflammation in transgenic experimental autoimmune cystitis models

New animal models are greatly needed in interstitial cystitis/painful bladder syndrome (IC/PBS) research. We recently developed a novel transgenic cystitis model (URO-OVA mice) that mimics certain key aspects of IC/PBS pathophysiology. This paper aimed to determine whether URO-OVA cystitis model was responsive to intravesical dimethyl sulfoxide (DMSO) and if so identify the mechanisms of DMSO action. URO-OVA mice developed acute cystitis upon adoptive transfer of OVA-specific OT-I splenocytes. Compared to PBS-treated bladders, the bladders treated with 50% DMSO exhibited markedly reduced bladder histopathology and expression of various inflammatory factor mRNAs. Intravesical DMSO treatment also effectively inhibited bladder inflammation in a spontaneous chronic cystitis model (URO-OVA/OT-I mice). Studies further revealed that DMSO could impair effector T cells in a dose-dependent manner in vitro. Taken together, our results suggest that intravesical DMSO improves the bladder histopathology of IC/PBS patients because of its ability to interfere with multiple inflammatory and bladder cell types.

Critical appraisal of dimethyl sulfoxide treatment for interstitial cystitis discomfort, side-effects and treatment outcome

OBJECTIVE

To evaluate the discomfort and long-term efficacy associated with instillation of dimethyl sulfoxide (DMSO).

MATERIAL AND METHODS

A total of 28 patients, 13 (11 females, 2 males) with classic interstitial cystitis (IC) and 15 (13 females, two males) with non-ulcer disease, who had received at least one series of six instillations of DMSO were studied. In addition to studying micturition diaries before and after the treatment, the evaluation included assessments of pain using a visual analog scale and of side-effects after each instillation in every series. Data were obtained by surveying the clinical records. A follow-up telephone interview was conducted for those patients who were treated with DMSO and in whom the treatment was considered successful. DMSO instillations were considered successful if the patient reported symptom amelioration and chose to continue with the treatment.

RESULTS

Side-effects were not more common or pronounced in patients with classic compared to non-ulcer IC. For classic IC a significant difference could be seen when comparing side-effects experienced during the first three instillations and the three subsequent instillations. After DMSO instillations, a residual treatment effect lasting 16-72 months could be seen.

CONCLUSIONS

Intravesical instillation therapy with DMSO appears to be a feasible treatment option for both subtypes of IC and is associated with a reasonably low degree of discomfort.

Gas chromatography-mass spectrometry assay for determination of Ntau-methylhistamine concentration in canine urine specimens and fecal extracts

OBJECTIVE

To develop and validate a gas chromatography-mass spectrometry (GC-MS) method for determination of Ntau-methylhistamine (NMH) concentration in canine urine and fecal extracts and to assess urinary NMH concentrations in dogs with mast cell neoplasia and fecal NMH concentrations in dogs with protein-losing enteropathy.

SAMPLE POPULATION

Urine specimens were collected from 6 healthy dogs and 7 dogs with mast cell neoplasia. Fecal extracts were obtained from fecal specimens of 28 dogs with various severities of protein-losing enteropathy, as indicated by fecal concentration of alpha1-proteinase inhibitor.

PROCEDURES

NMH was extracted directly from urine, and fecal specimens were first extracted into 5 volumes of PBSS containing 1% newborn calf serum. Ntau-methylhistamine in specimens was quantified via stable isotope dilution GC-MS. The assay was validated via determination of percentage recovery of known amounts of NMH and interassay coefficients of variation. Urinary excretion of NMH was evaluated by means of NMH-to-creatinine concentration ratios.

RESULTS

Recovery of NMH in urine and fecal extracts averaged 104.6% and 104.5%, respectively. Interassay coefficients of variation ranged from 5.4% to 11.7% in urine and 12.6% to 18.1% in fecal extracts. Urinary NMH excretion was significantly increased in dogs with mast cell neoplasia, compared with that in healthy dogs. No correlation was detected between severity of protein-losing enteropathy and fecal NMH concentration.

CONCLUSIONS AND CLINICAL RELEVANCE

This method provided a sensitive, reproducible means of measuring NMH in canine urine and fecal extracts. High urinary NMH-to-creatinine concentration ratios in dogs with mast cell neoplasia are consistent with increased histamine release in this disease.

Multidisciplinary utilization of dimethyl sulfoxide: pharmacological, cellular, and molecular aspects

DMSO is an amphipathic molecule with a highly polar domain and two apolar methyl groups, making it soluble in both aqueous and organic media. It is one of the most common solvents for the in vivo administration of several water-insoluble substances. Despite being frequently used as a solvent in biological studies and as a vehicle for drug therapy, the side-effects of DMSO (undesirable for these purposes) are apparent from its utilization in the laboratory (both in vivo and in vitro) and in clinical settings. DMSO is a hydrogen-bound disrupter, cell-differentiating agent, hydroxyl radical scavenger, intercellular electrical uncoupler, intracellular low-density lipoprotein-derived cholesterol mobilizing agent, cryoprotectant, solubilizing agent used in sample preparation for electron microscopy, antidote to the extravasation of vesicant anticancer agents, and topical analgesic. Additionally, it is used in the treatment of brain edema, amyloidosis, interstitial cystitis, and schizophrenia. Several systemic side-effects from the use of DMSO have been reported, namely nausea, vomiting, diarrhea, hemolysis, rashes, renal failure, hypertension, bradycardia, heart block, pulmonary edema, cardiac arrest, and bronchospasm. Looking at the multitude of effects of DMSO brought to light by these studies, it is easily understood how many researchers working with DMSO (or studying one of its specific effects) might not be fully aware of the experiences of other groups who are working with it but in a different context.

Targets for therapy of the painful bladder

Interstitial cystitis is an elusive disorder. Without a defining etiology and distinctive pathophysiology, diagnosis is made on an exclusionary basis. Treatment strategies for the disease vary, as do estimates of its prevalence. Nevertheless, advances are being made in understanding this disease. Basic research is helping to define rational treatment approaches for interstitial cystitis, and new therapies based on the findings of such research are being developed. This article reviews the theories of the etiology of interstitial cystitis and reviews the evidence for clinical effectiveness of various treatments.