Inhibition of interferon-gamma and interleukin-2 production from lymphocytes stimulated with food antigens by an anti-allergic drug, Tranilast, in patients with food-sensitive atopic dermatitis

Utility of a novel turn-off fluorescence probe for the determination of tranilast, an adjunctive drug for patients with severe COVID-19

Tranilast (TR) could be investigated as a suitable anti-inflammatory and NLRP3 inflammasome inhibitor medication for the treatment of COVID-19 acute patients. Owing to its importance, our study was constructed for the determination of TR using a new, fast, sensitive, and reliable green spectrofluorimetric method. TR was quantified in this study by forming a complex with the acriflavine (AC) reagent. The reaction between TR and AC quenched the fluorescence of AC through the formation of an ion-association complex and the response was measured at 493 nm after excitation at 263 nm. It was observed that the quenching of the fluorescence of AC was linear (r = 0.9998) with the concentration of TR in the range of 1.0–15.0 μg mL⁻¹. The limit of detection was 0.224 μg mL⁻¹, and the limit of quantification was 0.679 μg mL⁻¹. The fluorescence quenching mechanism was carefully studied and was confirmed to be able to analyze TR in its pure form and its prepared pharmaceutical dosage form. To validate the method, the international conference of harmonization (ICH) Q₂R₁ guidelines were followed. The statistical assessment of the proposed and comparison methods revealed no significant differences between them. Moreover, the green criteria of the method were evaluated and confirmed.

Tranilast (TR) could be investigated as an anti-inflammatory and NLRP3 inflammasome inhibitor medication using acriflavine.

Systemic treatments for eczema: a network meta-analysis

BACKGROUND

Eczema is a common and chronic, relapsing, inflammatory skin disorder. It seriously impacts quality of life and economic outcomes, especially for those with moderate to severe eczema. Various treatments allow sustained control of the disease; however, their relative benefit remains unclear due to the limited number of trials directly comparing treatments.

OBJECTIVES

To assess the comparative efficacy and safety of different types of systemic immunosuppressive treatments for moderate to severe eczema using NMA and to generate rankings of available systemic immunosuppressive treatments for eczema according to their efficacy and safety.

SEARCH METHODS

We searched the following databases up to August 2019: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, and Embase.

SELECTION CRITERIA

All randomised controlled trials (RCTs) of systemic immunosuppressive agents for moderate to severe atopic eczema when compared against placebo or any other eligible eczema treatment.

DATA COLLECTION AND ANALYSIS

We synthesised data using pair-wise analysis and NMA to compare treatments and rank them according to their effectiveness. Effectiveness was assessed primarily by determining the proportion of participants who achieved at least 75% improvement in the Eczema Area and Severity Index (EASI75) and improvement in the Patient-Oriented Eczema Measure (POEM). Safety was evaluated primarily by considering the proportion of participants with serious adverse events (SAEs) and infection. We deemed short-term follow-up as ≤ 16 weeks and long-term follow-up as > 16 weeks. We assessed the certainty of the body of evidence from the NMA for these primary outcomes using six domains of CiNEMA grading.

MAIN RESULTS

We included a total of 74 studies, with 8177 randomised participants. Approximately 55% of participants were male, with average age of 32 years (range 2 to 84 years), although age and gender were unreported for 419 and 902 participants, respectively. Most of the included trials were placebo controlled (65%), 34% were head-to-head studies (15% assessed the effects of different doses of the same drug), and 1% were multi-armed studies with both an active comparator and a placebo. All trials included participants with moderate to severe eczema, but 62% of studies did not separate data by severity; 38% of studies assessed only severe eczema. The total duration of included trials ranged from 2 weeks to 60 months, whereas treatment duration varied from a single dose (CIM331, KPL-716) to 60 months (methotrexate (MTX)). Seventy studies were available for quantitative synthesis; this review assessed 29 immunosuppressive agents from three classes of interventions. These included (1) conventional treatments, with ciclosporin assessed most commonly; (2) small molecule treatments, including phosphodiesterase (PDE)-4 inhibitors, tyrosine kinase inhibitors, and Janus kinase (JAK) inhibitors; and (3) biological treatments, including anti-CD31 receptors, anti-interleukin (IL)-22, anti-IL-31, anti-IL-13, anti-IL-12/23p40, anti-OX40, anti-TSLP, anti-CRTH2, and anti-immunoglobulin E (IgE) monoclonal antibodies, but most commonly dupilumab. Most trials (73) assessed outcomes at a short-term duration ranging from 2 to 16 weeks, whereas 33 trials assessed long-term outcomes, with duration ranging from 5 to 60 months. All participants were from a hospital setting. Fifty-two studies declared a source of funding, and of these, pharmaceutical companies funded 88%. We rated 37 studies as high risk; 21, unclear risk, and 16, low risk of bias, with studies most commonly at high risk of attrition bias. Network meta-analysis suggests that dupilumab ranks first for effectiveness when compared with other biological treatments. Dupilumab is more effective than placebo in achieving EASI75 (risk ratio (RR) 3.04, 95% confidence interval (CI) 2.51 to 3.69) and improvement in POEM score (mean difference 7.30, 95% CI 6.61 to 8.00) at short-term follow-up (high-certainty evidence). Very low-certainty evidence means we are uncertain of the effects of dupilumab when compared with placebo, in terms of the proportion of participants who achieve EASI75 (RR 2.59, 95% CI 1.87 to 3.60) at longer-term follow-up. Low-certainty evidence indicates that tralokinumab may be more effective than placebo in achieving short-term EASI75 (RR 2.54, 95% CI 1.21 to 5.34), but there was no evidence for tralokinumab to allow us to assess short-term follow-up of POEM or long-term follow-up of EASI75. We are uncertain of the effect of ustekinumab compared with placebo in achieving EASI75 (long-term follow-up: RR 1.17, 95% CI 0.40 to 3.45; short-term follow-up: RR 0.91, 95% CI 0.28 to 2.97; both very low certainty). We found no evidence on ustekinumab for the POEM outcome. We are uncertain whether other immunosuppressive agents that targeted our key outcomes influence the achievement of short-term EASI75 compared with placebo due to low- or very low-certainty evidence. Dupilumab and ustekinumab were the only immunosuppressive agents evaluated for longer-term EASI75. Dupilumab was the only agent evaluated for improvement in POEM during short-term follow-up. Low- to moderate-certainty evidence indicates a lower proportion of participants with SAEs after treatment with QAW039 and dupilumab compared to placebo during short-term follow-up, but low- to very low-certainty evidence suggests no difference in SAEs during short-term follow-up of other immunosuppressive agents compared to placebo. Evidence for effects of immunosuppressive agents on risk of any infection during short-term follow-up and SAEs during long-term follow-up compared with placebo was of low or very low certainty but did not indicate a difference. We did not identify differences in other adverse events (AEs), but dupilumab is associated with specific AEs, including eye inflammation and eosinophilia.

AUTHORS' CONCLUSIONS

Our findings indicate that dupilumab is the most effective biological treatment for eczema. Compared to placebo, dupilumab reduces eczema signs and symptoms in the short term for people with moderate to severe atopic eczema. Short-term safety outcomes from clinical trials did not reveal new safety concerns with dupilumab. Overall, evidence for the efficacy of most other immunosuppressive treatments for moderate to severe atopic eczema is of low or very low certainty. Given the lack of data comparing conventional with newer biological treatments for the primary outcomes, there remains high uncertainty for ranking the efficacy and safety of conventional treatments such as ciclosporin and biological treatments such as dupilumab. Most studies were placebo-controlled and assessed only short-term efficacy of immunosuppressive agents. Further adequately powered head-to-head RCTs should evaluate comparative long-term efficacy and safety of available treatments for moderate to severe eczema.

Determination of tranilast in bio-samples by LC-MS/MS: Application to a pharmacokinetic and brain tissue distribution study in rats

As a potent drug used to improve the neurodegenerative conditions, there is few information about the brain tissue distribution of tranilast by now. In this study, a novel sensitive LC-MS/MS method has been developed and validated to determine tranilast in rat brain tissue samples. The calibration curve showed good linearity ranged from 2.140 to 428.0ng·mL^-1. The method was fully validated and successfully applied in the brain tissue distribution study of tranilast in rats, which had never been reported in detail by now. Furthermore, a rapid LC-MS/MS method with a short run time of 3min was developed and validated for the determination of tranilast in rat plasma and the application to a pharmacokinetic study of tranilast in rats. After oral dosage of 10.5mg·kg^-1 tranilast, the maximum plasma concentration (C_max¹) of tranilast was (18.59±5.40) μg·mL^-1 at (0.667±0.408) h while the area under the curve (AUC_0-24) was (54.87±14.13) μg·h·mL^-1 with the elimination half-life of (2.93±0.41) h. The ratio calculated by dividing the concentration of tranilast in brain with the concentration of tranilast in the plasma, was (0.6042%±0.0572%), (0.7484%±0.0883%), (0.5914%±0.0416%) and (0.3830%±0.1632%) at 0.167, 0.5, 2 and 8h, respectively. The results showed that tranilast with fast absorption could penetrate the rat brain blood barrier after oral gavage. The obtained data also showed that tranilast could be quickly distributed and eliminated in brain tissue.

A Case of Vulvitis Granulomatosa

Merkersson-Rosenthal syndrome (MRS) is characterized by cheilitis or pareitis granulomatosa, facial palsy, and fissured tongue. Sometimes the forehead, eyelids and chin are involved, and occasionally genital lesions are present. A vulval lesion of MRS is named vulvitis granulomatosa. Tranilast has been described as an effective treatment for cases of MRS, granulomatous cheilitis, and granulomatous blepharitis. Herein we report a successful treatment with tranilast of an adult female patient with vulvitis granulomatosa.

Tranilast administration reduces fibrosis and improves fatigue resistance in muscles of mdx dystrophic mice

BACKGROUND

Duchenne muscular dystrophy (DMD) is a severe and progressive muscle-wasting disorder caused by mutations in the dystrophin gene that result in the absence of the membrane-stabilising protein dystrophin. Dystrophic muscle fibres are susceptible to injury and degeneration, and impaired muscle regeneration is associated with fibrotic deposition that limits the efficacy of potential pharmacological, cell- and gene-based therapies. Novel treatments that can prevent or attenuate fibrosis have important clinical merit for DMD and related neuromuscular diseases. We investigated the therapeutic potential for tranilast, an orally bioavailable anti-allergic agent, to prevent fibrosis in skeletal muscles of mdx dystrophic mice.

RESULTS

Three-week-old C57Bl/10 and mdx mice received tranilast (~300 mg/kg) in their food for 9 weeks, after which fibrosis was assessed through histological analyses, and functional properties of tibialis anterior muscles were assessed in situ and diaphragm muscle strips in vitro. Tranilast administration did not significantly alter the mass of any muscles in control or mdx mice, but it decreased fibrosis in the severely affected diaphragm muscle by 31% compared with untreated mdx mice (P < 0.05). A similar trend of decreased fibrosis was observed in the tibialis anterior muscles of mdx mice (P = 0.10). These reductions in fibrotic deposition were not associated with improvements in maximum force-producing capacity, but we did observe small but significant improvements in the resistance to fatigue in both the diaphragm and TA muscles of mdx mice treated with tranilast.

CONCLUSION

Together these findings demonstrate that administration of potent antifibrotic compounds such as tranilast could help preserve skeletal muscle structure, which could ultimately increase the efficacy of pharmacological, cell and gene replacement/correction therapies for muscular dystrophy and related disorders.

Lymphocyte Responses to Chymotrypsin- or Trypsin V-Digested beta-Lactoglobulin in Patients with Cow's Milk Allergy

Chymotrypsin- or trypsin V- (a mixture of trypsin and chymotrypsin) digested β-lactoglobulin (BLG) peptides were prepared and were confirmed to have much less immunoglobulin (lg)G and lgE reactivity compared with intact BLG by IgG inhibition enzymelinked immunosorbent assay and IgE dot blotting. The lymphocyte responses to intact BLG and these peptides were examined using peripheral blood mononuclear cells (PBMCs) from 10 patients with cow's milk allergy. The PBMCs from most patients had lower lymphocyte responses to chymotrypsin- and trypsin V-digested BLG peptides than those to intact BLG. However, PBMCs from one and two patients retained significant proliferative responses to both peptides and to only the former peptide, respectively. Interferon-c production stimulated by chymotrypsin-digested peptides was still detectable in all five patients tested. Chymotrypsindigested BLG reduced lgE reactivity but still induced some lymphocyte responses.

Enhanced IL-4 but normal interferon-gamma production in children with isolated IgE mediated food hypersensitivity

Atopic disorders such as atopic dermatitis and asthma have been characterised by an imbalance in interferon-gamma (INF-gamma) and IL-4. Whether similar imbalances are found in atopic disorders with different clinical manifestations, such as IgE mediated immediate food hypersensitivity, is not clear. We have examined the in vitro production of INF-gamma and IL-4 in peripheral blood mononuclear cells (PBMC) following phytohaemagglutinin stimulation from children with isolated immediate IgE mediated food hypersensitivity (egg, milk, "nut"), children with moderate and severe atopic dermatitis, and normal children. Children with immediate food reactions were excluded if they had a history or evidence of atopic dermatitis or asthma. PBMC from children with IgE mediated food hypersensitivity produced significantly more IL-4 (p = 0.013) but equivalent INF-gamma (p = 0.26) compared to PBMC from control children. In contrast, PBMC from children with atopic dermatitis produced significantly less INF-gamma (p < 0.001) and more IL-4 (p < 0.008) than PBMC from normal children. In addition, there was no difference in IL-4 (p = 0.74) but significantly less INF-gamma (p < 0.001) produced by PBMC from the children with atopic dermatitis than food hypersensitivity. We demonstrate that children with IgE mediated food hypersensitivity and no other manifestation of atopic disease have enhanced IL-4 production without the defect in INF-gamma production observed in childhood AD and asthma. We postulate that isolated IL-4 enhancement promotes the development of IgE mediated hypersensitivity disorders such as food allergy, whilst the combination of defective INF-gamma and enhanced IL-4 production promotes inflammatory atopic disorders such as AD and asthma.