Correlation between the expression of the iNOS, caspase-3 and α-SMA genes in the parotid glands of albino rats following the administration of two antihistamines from two different generations.

BACKGROUND: Several medications, including antihistamines, can alter salivary gland function, causing dry mouth or xerostomia. Antihistamines are commonly used for treating allergic rhinitis. OBJECTIVES: The aim of the present study was to compare and correlate the effects of first-generation vs. second-generation H1-antihistamines on the parotid glands of rats. MATERIAL AND METHODS: Twelve adult male albino rats were used; 4 rats served as a control group (group I) and the remaining rats were divided into 2 groups: group II received promethazine hydrochloride; and group III received cetirizine dihydrochloride for 3 weeks. The parotid salivary glands were dissected, and examined histologically and analyzed histomorphometrically for the acinar area percentage. In addition, mRNA gene expression of iNOS, caspase-3 and α-SMA was assessed using quantitative realtime polymerase chain reaction (qRT-PCR). Finally, all the obtained data was statistically analyzed. RESULTS: Histologically, group I showed the typical architecture of the gland. In group II, degenerative changes were noticed, including acinar degeneration and shrinkage with widened connective tissue septa, intracellular vacuolization, and increased inflammatory cell infiltration. In group III, similar histological features were detected as in group II, but to a lesser extent. Histomorphometric results revealed significant differences in the acinar area percentage between various groups. In addition, qRT-PCR results showed a significant increase in iNOS expression in both groups II and III as compared to group I, caspase-3 gene expression was significantly increased in group II, while in group III, it increased non-significantly. Finally, α-SMA gene expression non-significantly decreased in both groups II and III. A significant positive correlation was observed between caspase-3 and iNOS gene expression, while an inverse correlation was noticed between caspase-3 and α-SMA gene expression. CONCLUSIONS: The administration of antihistamines resulted in changes in the rat salivary glands, which could be due to the induction of oxidative stress and the resultant apoptotic effect. These changes were suggested to occur mainly through action on muscarinic receptors; yet, action on histamine receptors could not be excluded. However; these effects were less marked with the second-generation antihistamine.

Anti-edematous effects of epinastine, cetirizine and its enantiomers in λ-carrageenan-induced edema in rat hind paw.

Urticaria is induced by the histamine released from mast cells which develops wheals (edema) as a visual feature. In clinical practice, second-generation histamine H1 -receptor blockers are routinely used as the first-line symptomatic treatment for urticaria. Nevertheless, not much research has directly examined the second-generation histamine H1-receptor blockers' ability to reduce edema. In this study, we directly evaluated the anti-edematous activities of three second-generation histamine H1-receptor blockers available in the market (epinastine hydrochloride, cetirizine hydrochloride, and levocetirizine hydrochloride) using a λ-carrageenan-induced footpad edema model. One hour before the induction of edema with 1% λ -carrageenan injection, all second-generation histamine H1 -receptor blockers (5, 10, 50 and 100 mg/kg) were subcutaneously administered to rats. At 0.5 and 3 hours after λ -carrageenan administration, the edema volume was evaluated using a Plethysmometer. Epinastine hydrochloride significantly suppressed the edema growth in a dose-dependent manner. Cetirizine hydrochloride showed a slight anti-edematous effect, while levocetirizine significantly inhibited the development of edema in a dose-dependent manner. On the other hand, dextrocetirizine did not prevent edema from growing. In summary, second-generation histamine H1 -receptor blockers, at least those examined in this study, may be able to reduce the clinical symptoms of urticaria associated with edema. Levocetirizine hydrochloride is also anticipated to have stronger anti-edematous effects than cetirizine hydrochloride because levocetirizine is responsible for cetirizine's anti-edematous activity.

Microliquid/Liquid Interfacial Sensors: Biomimetic Investigation of Transmembrane Mechanisms and Real-Time Determinations of Clemastine, Cyproheptadine, Epinastine, Cetirizine, and Desloratadine.

Antihistamines relieve allergic symptoms by inhibiting the action of histamine. Further understanding of antihistamine transmembrane mechanisms and optimizing the selectivity and real-time monitoring capabilities of drug sensors is necessary. In this study, a micrometer liquid/liquid (L/L) interfacial sensor has served as a biomimetic membrane to investigate the mechanism of interfacial transfer of five antihistamines, i.e., clemastine (CLE), cyproheptadine (CYP), epinastine (EPI), desloratadine (DSL), and cetirizine (CET), and realize the real-time determinations. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques have been used to uncover the electrochemical transfer behavior of the five antihistamines at the L/L interface. Additionally, finite element simulations (FEMs) have been employed to reveal the thermodynamics and kinetics of the process. Visualization of antihistamine partitioning in two phases at different pH values can be realized by ion partition diagrams (IPDs). The IPDs also reveal the transfer mechanism at the L/L interface and provide effective lipophilicity at different pH values. Real-time determinations of these antihistamines have been achieved through potentiostatic chronoamperometry (I-t), exhibiting good selectivity with the addition of nine common organic or inorganic compounds in living organisms and revealing the potential for in vivo pharmacokinetics. Besides providing a satisfactory surrogate for studying the transmembrane mechanism of antihistamines, this work also sheds light on micro- and nano L/L interfacial sensors for in vivo analysis of pharmacokinetics at a single-cell or single-organelle level.

Efficacy of levocetirizine in isolated rat tracheal smooth muscle.

Histamine receptor-1 (H1) antagonists like levocetirizine are frequently used nowadays to treat rhinitis patients who experience rhinorrhea and sneezing. The trachea may be affected by the H1 antagonist when it is used to treat nasal symptoms, either orally or through inhalation. The purpose of this study was to ascertain in vitro effects of levocetirizine on isolated tracheal smooth muscle. As a parasympathetic mimetic, methacholine (10-6 M) causes contractions in tracheal smooth muscle, which is how we tested effectiveness of levocetirizine on isolated rat tracheal smooth muscle. We also tested the drug's impact on electrically induced tracheal smooth muscle contractions. The impact of menthol (either before or after) on the contraction brought on by 10-6 M methacholine was also investigated. According to the results, the addition of levocetirizine at concentrations of 10-5 M or more caused a slight relaxation in response to methacholine's 10-6 M contraction. Levocetirizine could prevent spike contraction brought on by electrical field stimulation (EFS). As the concentration rose, it alone had a neglect effect on the trachea's basal tension. Before menthol was applied, levocetirizine might have also inhibited the function of the cold receptor. According to this study, levocetirizine might potentially impede the parasympathetic function of the trachea. If levocetirizine was used prior to menthol addition, it also reduced the function of cold receptors.

Histamine H1 receptor antagonist attenuates catecholamine surge and organ injury after severe burns.

Severe burns induce a catecholamine surge, causing severe damage to the organism and raising the possibility of multisystem organ failure. Few strategies are generally acceptable to reduce catecholamine surge and organ injury post-burn. We have previously shown that histamine can amplify the catecholamine surge. In addition, promethazine, a first-generation histamine H1 receptor antagonist, alleviates catecholamine surge and organ injury after severe burns in rats. However, evidence is lacking on whether promethazine benefits patients after severe burns. Currently, sedation and analgesia (such as midazolam and fentanyl) are commonly required for patients after severe burns. It remains unclear if patients after severe burns derive clinical benefit from histamine H1 receptor antagonists combined with sedation and analgesia. This study investigates the therapeutic effect of promethazine on patients after severe burns. Moreover, we test the therapeutic effect of cetirizine, a second-generation histamine H1 receptor antagonist, combined with sedation and analgesia in rats after severe burns. We find that promethazine-pethidine treatment shows a tendency for a lower level of total bilirubin than midazolam-fentanyl in patients 7-day after severe burn. Our study confirms that cetirizine combined with midazolam and fentanyl reduces catecholamine surge and liver and lung damage after severe burns in rats; the effects are better than midazolam and fentanyl treatment. In summary, for the first time, we suggest that histamine H1 receptor antagonist has the potential clinical value of reducing liver injury in patients after severe burns. In addition, we reveal that cetirizine combined with midazolam and fentanyl may be an ideal strategy for treating severe burns.

Comparison between topical cetirizine with minoxidil versus topical placebo with minoxidil in female androgenetic alopecia: a randomized, double-blind, placebo-controlled study.

Androgenetic alopecia (AGA) is the most common cause of hair loss in both genders with a higher psychological impact on females. Currently, topical minoxidil is the only FDA-approved treatment for female AGA and it needs life-long application and causes side effects. Cetirizine is an antihistamine that may be effective in hair loss treatment. This study aimed to compare the efficacy and safety of topical cetirizine with minoxidil (group 1) versus topical minoxidil with placebo (group 2) in female patients with AGA. This was a double-blind, randomized, controlled, parallel study conducted at Dermatology Clinic, Cairo University Teaching Hospital (Kasr- Al- Ainy), Egypt. Sixty-six patients with female AGA, aged 20-50 years, Sinclair (II-IV), were randomly assigned to one of the 2 groups for 24 weeks. The trichoscopic parameters, patients' self-assessment, side effects and global photographic assessment were evaluated. There was a statistically significant change from baseline in frontal and vertex terminal and vellus hair density (P < 0.0005) with a significant increase in vertex hair shaft thickness and average number of hairs per follicular unit in group 1 (P < 0.05). Patients reported significantly better scores in patient self-assessment in group 1 (P < 0.05). Side effects were not significantly different between groups (P > 0.05). Topical cetirizine increases hair shaft thickness and results in a higher clinical improvement from patients' perspective with a good safety profile (NCT04481412, study start date: July 2020).

Effects of second-generation H1-antihistamine drugs on angiogenesis in in vivo chick chorioallantoic membrane model.

BACKGROUND: Literature on the effects of second-generation H1-antihistamines on angiogenesis is limited. OBJECTIVES: To investigate the effects of cetirizine, desloratadine, and rupatadine (second-generation H1-antihistamines commonly used in dermatology clinics) on angiogenesis in an in vivo chick chorioallantoic membrane (CAM) model. METHODS: The study was approved by the local ethics committee on animal experimentation. Forty fertilized specific pathogen free eggs were incubated and kept under appropriate temperature and humidity control. Drug solutions were prepared in identical concentrations by dissolving powders in phosphate-buffered saline (PBS). On the third day of the incubation, a small window was opened on the CAM and 0.1 mL desloratadine (1.5 µg/0.1 mL) in the first group, 0.1 mL cetirizine (1.5 µg/0.1 mL) in the second group, 0.1 mL rupatadine in the third group (1.5 µg/0.1 mL), and PBS (0.1 mL) in the fourth group were administered by injection. On the eighth day of incubation, the vascular structures of the CAMs were macroscopically examined and standard digital photographs were taken. The digital images were analyzed and data including mean vessel density, thickness, and number were compared between groups. p < 0.05 was considered statistically significant. RESULTS: Vessel densities were similar in the desloratadine, cetirizine, and control groups, whereas they were significantly less in the rupatadine group (p = 0.01). Furthermore, the rupatadine group had significantly lower vessel thickness and number compared with the other groups (p < 0.05 for both). CONCLUSIONS: Rupatadine showed anti-angiogenic effects in the chick CAM model, compared with desloratadine and cetirizine. The anti-angiogenic effect of rupatadine could be due to its platelet-activating factor (PAF) receptor inhibition. Thus, rupatadine could be a treatment agent in pathological processes in which angiogenesis is responsible. Further studies with larger series are needed to clarify this potential.

Pharmacological activation of mediodorsal thalamic GABA-A receptors modulates morphine/cetirizine-induced changes in the prefrontal cortical GFAP expression in a rat model of neuropathic pain.

The present study investigated the involvement of mediodorsal thalamic (MD) GABA-A receptors in cetirizine/morphine-induced anti-allodynia using a rat model of neuropathic pain. To assess the importance of the prefrontal cortex (PFC) for chronic pain processing, its expression level changes of glial fibrillary acidic protein (GFAP) were measured following drug treatments. Each animal was subjected to chronic constriction of the sciatic nerve surgery simultaneously with the MD cannulation under stereotaxic surgery. The results showed that the administration of morphine (3-5 mg/kg) or cetirizine (1-3 mg/kg) produced significant analgesia in neuropathic rats. Systemic administration of cetirizine (2.5 and 3 mg/kg) potentiated the analgesic response to a low and intolerance dose of morphine (3 mg/kg). Intra-MD microinjection of muscimol, a selective GABA-A receptor agonist (0.005-0.01 µg/rat), increased the cetirizine/morphine-induced anti-allodynia, while muscimol by itself did not affect neuropathic pain. The neuropathic pain was associated with the increased PFC expression level of GFAP, suggesting the impact of chronic pain on PFC glial management. Interestingly, the anti-allodynia was associated with a decrease in the PFC expression level of GFAP under the drugs' co-administration. Thus, cetirizine has a significant potentiating effect on morphine response in neuropathic pain via interacting with the MD GABA-A receptors. It seems that neuropathic pain affects the prefrontal cortex GFAP signaling pathway. In clinical studies, these findings can be considered to create a combination therapy with low doses of GABA-A receptor agonist plus cetirizine and morphine to manage neuropathic pain.

Cetirizine more potently exerts mast cell-stabilizing property than diphenhydramine.

Cetirizine, a second-generation antihistamine, and diphenhydramine, a first-generation antihistamine, are among the most widely used anti-allergic drugs. In addition to longer duration of action and less incidence of sedative side effects, recent clinical studies also indicate a higher potency of cetirizine than diphenhydramine in the treatment or prevention of allergic disorders. In the present study, using the differential-interference contrast (DIC) microscopy, we examined the effects of cetirizine and diphenhydramine (1 µM to 1 mM) on the degranulation from rat peritoneal mast cells. Using fluorescence imaging of a water-soluble dye, lucifer yellow, we also examined their effects on the deformation of the plasma membrane. At relatively higher concentrations (100 µM, 1 mM), both cetirizine and diphenhydramine significantly reduced the numbers of degranulating mast cells. Of note, at 1 mM, cetirizine more markedly reduced the number than diphenhydramine, almost entirely suppressing the degranulation of mast cells. Additionally, 1 mM cetirizine and levocetirizine, another second-generation antihistamine, almost totally inhibited the process of exocytosis in mast cells and washed out the trapping of the lucifer yellow on the cell surface, while diphenhydramine and chlorpheniramine, another first-generation antihistamine, did not. This study provided in vitro evidence for the first time that cetirizine more potently inhibited the process of exocytosis in mast cells than diphenhydramine, indicating its higher potency as a mast cell-stabilizer. Such mast cell-stabilizing property of cetirizine could be ascribed to its counteracting effect on the plasma membrane deformation in degranulating mast cells.

Concomitant medication of cetirizine in advanced melanoma could enhance anti-PD-1 efficacy by promoting M1 macrophages polarization.

BACKGROUND: The clinical observation showed a potential additive effect of anti-PD-1 agents and cetirizine in patients with advanced melanoma. METHODS: Clinical outcomes of concomitant cetirizine/anti-PD-1 treatment of patients with stage IIIb-IV melanoma were retrospectively collected, and a transcriptomic analysis was performed on blood samples obtained at baseline and after 3 months of treatment. RESULTS: Patients treated with cetirizine concomitantly with an anti-PD-1 agent had significantly longer progression-free survival (PFS; mean PFS: 28 vs 15 months, HR 0.46, 95% CI: 0.28-0.76; p = 0.0023) and OS (mean OS was 36 vs 23 months, HR 0.48, 95% CI: 0.29-0.78; p = 0.0032) in comparison with those not receiving cetirizine. The concomitant treatment was significantly associated with ORR and DCR (p < 0.05). The expression of FCGR1A/CD64, a specific marker of macrophages, was increased after the treatment in comparison with baseline in blood samples from patients receiving cetirizine, but not in those receiving only the anti-PD1, and positively correlated with the expression of genes linked to the interferon pathway such as CCL8 (rho = 0.32; p = 0.0111), IFIT1 (rho = 0.29; p = 0.0229), IFIT3 (rho = 0.57; p < 0.0001), IFI27 (rho = 0.42; p = 0.008), MX1 (rho = 0.26; p = 0.0383) and RSAD2 (rho = 0.43; p = 0.0005). CONCLUSIONS: This retrospective study suggests that M1 macrophage polarization may be induced by cetirizine through the interferon-gamma pathway. This effect may synergize with the immunotherapy of advanced melanoma with anti-PD-1 agents.

[Cetirizine inhibits activation of JAK2-STAT3 pathway and mast cell activation in lung tissue of asthmatic mice].

Objective To investigate the effects of cetirizine on Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) pathway and mast cell activation in asthmatic mice by establishing a mouse model of asthma. Methods Sixty SPF BALB/c mice (10 in each group) were divided into control group, model group, low-dose cetirizine group (2 mg/kg), high-dose cetirizine group (5 mg/kg), cetirizine combined with AG490 group (5 mg/kg cetirizine combined with 0.4 mg/kg AG490). The asthma model was established by ovalbumin(OVA) sensitization and eliciting. Each treatment group was given certain amount of cetirizine by gavage every day, and the cetirizine combined with AG490 group was given intraperitoneal injection of 0.4 mg/kg AG490 once a week; the control group was given the same dose of normal saline until the end of modeling. The level of histamine in serum was detected by ELISA; the total number of cells in bronchoalveolar lavage fluid (BALF) was counted; the pathological changes of lung tissue were detected by HE staining; the expression of tryptase in lung tissue was detected by immunohistochemical staining; the expressions of pathway related proteins were detected by Western blot analysis. Results Compared with those in the control group, the level of histamine in serum, the total number of BALF cell, the eosinophilia count, the degree of lung pathological injury, and the expressions of tryptase, p-JAK2/JAK2, and p-STAT3/STAT3 in the model group were significantly higher; compared with those in the model group, the level of histamine in serum, the total number of BALF cell, the eosinophilia count, the degree of lung pathological injury, and the expressions of tryptase, p-JAK2/JAK2, and p-STAT3/STAT3 in low-dose group, high-dose group, and cetirizine combined with AG490 group were significantly lower; compared with those in the high-dose group, the level of histamine in serum, the total number of BALF cell, the eosinophilia count, the degree of lung pathological injury, and the expressions of tryptase and p-STAT3/STAT3 in cetirizine combined with AG490 group were significantly lower, however, the expression of p-JAK2/JAK2 had no significant change. Conclusion Cetirizine inhibits JAK2-STAT3 pathway activation and mast cell activation in lung tissue of asthmatic mice.

Comparison of Carbon Dots Prepared in Deep Eutectic Solvent and Water/Deep Eutectic Solvent: Study of Fluorescent Detection of Fe3+ and Cetirizine and their Photocatalytic Antibacterial Activity.

In this study, two solvents (deep eutectic and water/deep eutectic solvents) were used for N-doped carbon dots (N-CDs) preparation by microwave irradiation. The solvent can influence surface chemical composition, quantum yield, morphology, and fluorescence of CDs. N-CDs synthesized in water/deep eutectic solvent (DES) had better quantum yield (24.5%) with respect to N-CDs synthesized in deep eutectic solvent (17.4%). These carbon dots were used as a rapid and high sensitive "off-on" fluorescent probe for the determination of Fe3+ ion and cetirizine. Morphology and structure of the N-CDs were characterized by FT-IR, UV-Vis, XRD and TEM. Linear range and detection limit for N-CDs synthesis in deep eutectic solvent for cetirizine were 0.08-48 µM and 15 nM, respectively and for N-CDs synthesis in water/deep eutectic solvent were 0.03-50 µM and 10 nM, respectively. Applicability of this nanoprobe was tested in cetirizine determination in serum sample. Antibacterial activities of the two synthesized N-CDs were also investigated using agar disk diffusion method.

Effects of histamine and various histamine receptor antagonists on gene expression profiles of macrophages during compressive strain.

PURPOSE: Tissue hormone histamine can accumulate locally within the periodontal ligament via nutrition or may be released during allergic reactions by mast cells, which may have an impact on orthodontic tooth movement. In addition to periodontal ligament fibroblasts, cells of the immune system such as macrophages are exposed to compressive strain. The aim of this study was thus to investigate the impact of histamine on the gene expression profile of macrophages in the context of simulated orthodontic compressive strain. METHODS: Macrophages were incubated with different histamine concentrations (50, 100, 200 µM) for 24 h and then either left untreated or compressed for another 4 h. To assess the role of different histamine receptors, we performed experiments with antagonists for histamine 1 receptor (cetirizine), histamine 2 receptor (ranitidine) and histamine 4 receptor (JNJ7777120) under control and pressure conditions. We tested for lactate dehydrogenase release and analyzed the expression of genes involved in inflammation and bone remodeling by reverse transcription quantitative polymerase chain reaction (RT-qPCR). RESULTS: Histamine elevated gene expression of tumor necrosis factor under control conditions and in combination with pressure application. Increased prostaglandin-endoperoxide synthase­2 mRNA was observed when histamine was combined with compressive force. Interleukin­6 gene expression was not affected by histamine treatment. In macrophages, compressive strain increased osteoprotegerin gene expression. Histamine further elevated this effect. Most of the observed histamine effects were blocked by the histamine 1 receptor antagonist cetirizine. CONCLUSIONS: Histamine has an impact on the gene expression profile of macrophages during compressive strain in vitro, most likely having an impairing effect on orthodontic tooth movement by upregulation of osteoprotegerin expression.

Central histaminergic transmission modulates the expression of chronic nicotine withdrawal induced anxiety-like and somatic behavior in mice.

The present study investigated the plausible modulatory role of central histaminergic transmission on the expression of nicotine withdrawal induced anxiety and somatic behavior in mice. Abrupt cessation of chronic nicotine (2 mg/kg, i.p. × 3/day) treatment for 12 days to mice, expressed increased anxiety in light & dark test and total abstinence (somatic) score at 24 h post nicotine withdrawal time. The somatic signs includes a composite score of all behaviors such as grooming, rearing, jumping, body shakes, forelimb tremors, head shakes, abdominal constrictions, scratching, empty mouth chewing or teeth chattering, genital licking, tail licking. Mice exhibited higher expression to nicotine withdrawal induced anxiety in light & dark test at 24 h post-nicotine withdrawal time on pre-treatment centrally (i.c.v) with histaminergic agents like histamine (0.1, 50 µg/mouse), histamine H3 receptor inverse agonist, thioperamide (2, 10 µg/mouse), histamine H1 receptor agonist, FMPH (2, 6.5 µg/mouse) or H2 receptor agonist amthamine (0.1, 0.5 µg/mouse) or intraperitoneally (i.p.) with histamine precursor, l-histidine (250, 500 mg/kg) as compared to control nicotine withdrawn animals. Furthermore, mice pre-treated with all these histaminergic agents except histamine H1 receptor agonist, FMPH shows exacerbated expression to post-nicotine withdrawal induced total abstinence (somatic) score in mice. On the other hand, central injection of selective histamine H1 receptor antagonist, cetirizine (0.1 µg/mouse, i.c.v.) or H2 receptor antagonist, ranitidine (50 µg/mouse, i.c.v) to mice 10 min before 24 h post-nicotine withdrawal time completely alleviated the expression of nicotine withdrawal induced anxiety and somatic behavior. Thus, it can be contemplated that the blockade of central histamine H1 or H2 receptor during the nicotine withdrawal phase could be a novel approach to mitigate the nicotine withdrawal associated anxiety-like manifestations. Contribution of endogenous histamine via H1 or H2 receptor stimulation in the nicotine withdrawal induced anxiety and somatic behavior is proposed.

Effects of histamine on human periodontal ligament fibroblasts under simulated orthodontic pressure.

As type-I-allergies show an increasing prevalence in the general populace, orthodontic patients may also be affected by histamine release during treatment. Human periodontal ligament fibroblasts (PDLF) are regulators of orthodontic tooth movement. However, the impact of histamine on PDLF in this regard is unknown. Therefore PDLF were incubated without or with an orthodontic compressive force of 2g/cm2 with and without additional histamine. To assess the role of histamine-1-receptor (H1R) H1R-antagonist cetirizine was used. Expression of histamine receptors and important mediators of orthodontic tooth movement were investigated. PDLF expressed histamine receptors H1R, H2R and H4R, but not H3R. Histamine increased the expression of H1R, H2R and H4R as well as of interleukin-6, cyclooxygenase-2, and prostaglandin-E2 secretion even without pressure application and induced receptor activator of NF-kB ligand (RANKL) protein expression with unchanged osteoprotegerin secretion. These effects were not observed in presence of H1R antagonist cetirizine. By expressing histamine receptors, PDLF seem to be able to respond to fluctuating histamine levels in the periodontal tissue. Increased histamine concentration was associated with enhanced expression of proinflammatory mediators and RANKL, suggesting an inductive effect of histamine on PDLF-mediated osteoclastogenesis and orthodontic tooth movement. Since cetirizine inhibited these effects, they seem to be mainly mediated via histamine receptor H1R.

Evaluation of the Effect of 5 QT-Positive Drugs on the JTpeak Interval - An Analysis of ECGs From the IQ-CSRC Study.

The JTpeak interval has been proposed as a new biomarker to demonstrate mixed ion channel effects, potentially leading to reduced late-stage electrocardiogram (ECG) monitoring for mildly QT-prolonging drugs. ECG waveforms from the IQ-CSRC study were used. Twenty healthy subjects were enrolled with 6 subjects on placebo and 9 subjects on each of 5 mildly QT-prolonging drugs - moxifloxacin, dofetilide, ondansetron, dolasetron, and quinine - and 1 negative drug, levocetirizine. A vector magnitude lead was derived from 12-lead ECGs, and measurements were made on a median beat from three 10-second replicates. Data were analyzed using a linear concentration-response model with QTcF and heart rate corrected JTpeak (JTpeak_c) as dependent variables. For moxifloxacin, dofetilide, and ondansetron, all pure hERG blockers, slopes of the concentration (C)-QTcF and C-JTpeak_c relationships were positive and statistically significant. With the prespecified linear model, the predicted effects on ΔΔQTcF and ΔΔJTpeak_c were 11.4 and 9.4 milliseconds for moxifloxacin at the geometric mean Cmax on day 1, 9.0 and 11.7 milliseconds for dofetilide and 11.5, and 7.9 milliseconds for ondansetron, respectively. In contrast, dolasetron and quinine, both with additional ion channel effects, prolonged QTcF with a positive C-ΔQTcF slope and predicted ΔΔQTcF effect on day 1 of 6.2 and 11.4 milliseconds, whereas the C-ΔJTpeak_c slope and the predicted ΔΔJTpeak on day 1 were negative (-0.3 and -7.5 milliseconds per ng/mL). Pure hERG-blocking drugs prolonged both the QTc and the JTpeak_c intervals, whereas drugs with mixed ion channel effects, including peak sodium inhibition, prolonged QTcF but not the JTpeak_c interval.

Antipruritic Placebo Effects by Conditioning H1-antihistamine.

OBJECTIVE: Allergic rhinitis symptoms can be reduced by behaviorally conditioning antihistamine. It is unclear whether these findings extend to histamine-induced itch or work when participants are informed about the conditioning procedure (open-label conditioning). The current study aims to investigate the efficacy of (open-label) antipruritic behavioral conditioning for histamine-induced itch. METHODS: Healthy participants (n = 92; 84% female) were randomized to I) an open-label conditioned, II) closed-label conditioned, III) conditioned-not-evoked control, or IV) nonconditioned control group. A two-phase conditioning paradigm was used. During acquisition, a conditioned stimulus (CS; distinctively tasting beverage) was repeatedly paired with the H1-antihistamine levocetirizine (groups I-III). During evocation, the CS was paired with placebo (I, II), or instead of the CS, water was paired with placebo (III). The nonconditioned control group (IV) received CS with placebo in both phases. Itch after histamine iontophoresis and physiological data (i.e., spirometry, heart rate, skin conductance) were assessed. Combined conditioned and combined control groups were first compared, and analyses were repeated for separate groups. RESULTS: Marginally lower itch was reported in the combined conditioned compared with the control groups (F(1,88) = 2.10, p = .076, ηpartial = 0.02); no differences between separate groups were found. No effects on physiological data were found, except for heart rate, which reduced significantly and consistently for control groups, and less consistently for conditioned groups (group by time interaction: F(7,80) = 2.35, p = .031, ηpartial = 0.17). CONCLUSION: Limited support was found for the efficacy of antipruritic behavioral conditioning, regardless of whether participants were informed about the conditioning procedure. The application of open-label conditioning in patient populations should be further researched. TRIAL REGISTRATION: www.trialregister.nl; ID NTR5544.

Vesiculobullous Darier Disease Symptomatically Responsive to Cetirizine

Darier disease is an autosomal dominant genodermatosis of abnormal keratinization characterized by hyperkeratotic papules and plaques with a predilection for seborrheic areas. We report a case of a rare vesiculobullous variant of treatment-resistant Darier disease in a 55-year-old woman that failed topical tacrolimus and topical and oral glucocorticoids. Cetirizine was initiated at 10 mg daily and increased to 40 mg daily over four weeks, with resultant marked improvement of the patient's burning sensation. A punch biopsy revealed a perivascular infiltrate of eosinophils. This patient's symptomatic improvement with cetirizine, which has antagonizing properties against eosinophils, highlights the potential role of eosinophils in the pathogenesis of vesiculobullous Darier disease. We suggest that major basic protein secreted by eosinophils may propagate blister formation in vesiculobullous Darier disease by disrupting desmosomes. J Drugs Dermatol. 2019;18(2):213-214.