Spectroscopic, electrochemical, and molecular docking studies of the interaction between the antihistamine drug desloratadine and dsDNA.

Through the utilization of fluorescence spectroscopy, electrochemical, and molecular docking methods, this research investigates the interaction between the antihistamine drug desloratadine and calf thymus double-stranded DNA (ct-dsDNA). Deoxyguanosine (dGuo) and deoxyadenosine (dAdo) oxidation signals were diminished by incubation with varying concentrations of desloratadine, as determined by differential pulse voltammetry (DPV). This change was ascribed to desloratadine's binding mechanism to ct-dsDNA. The binding constant (Kb) between desloratadine and ct-dsDNA was determined to be 2.2 × 105 M-1 throughout electrochemical experiments. In order to further develop our comprehension of the interaction mechanism between desloratadine and ct-dsDNA, a series of spectroscopic experiments and molecular docking simulations were conducted. The Kb value was found to be 8.85 × 104 M-1 at a temperature of 25 °C by the use of fluorescence spectroscopic techniques. In summary, the utilization of electrochemical and spectroscopic techniques, alongside molecular docking investigations, has led to the prediction that desloratadine has the capability to interact with ct-dsDNA by groove binding.

Desloratadine ameliorates paclitaxel-induced peripheral neuropathy and hypersensitivity reactions in mice.

Paclitaxel (PTX) serves as a primary chemotherapy agent against diverse solid tumors including breast cancer, lung cancer, head and neck cancer and ovarian cancer, having severe adverse effects including PTX-induced peripheral neuropathy (PIPN) and hypersensitivity reactions (HSR). A recommended anti-allergic agent diphenhydramine (DIP) has been used to alleviate PTX-induced HSR. Desloratadine (DLT) is a third generation of histamine H1 receptor antagonist, but also acted as a selective antagonist of 5HTR2A. In this study we investigated whether DLT ameliorated PIPN-like symptoms in mice and the underlying mechanisms. PIPN was induced in male mice by injection of PTX (4 mg/kg, i.p.) every other day for 4 times. The mice exhibited 50% reduction in mechanical threshold, paw thermal response latency and paw cold response latency compared with control mice. PIPN mice were treated with DLT (10, 20 mg/kg, i.p.) 30 min before each PTX administration in the phase of establishing PIPN mice model and then administered daily for 4 weeks after the model was established. We showed that DLT administration dose-dependently elevated the mechanical, thermal and cold pain thresholds in PIPN mice, whereas administration of DIP (10 mg/kg, i.p.) had no ameliorative effects on PIPN-like symptoms. We found that the expression of 5HTR2A was selectively elevated in the activated spinal astrocytes of PIPN mice. Spinal cord-specific 5HTR2A knockdown by intrathecal injection of AAV9-5Htr2a-shRNA significantly alleviated the mechanical hyperalgesia, thermal and cold hypersensitivity in PIPN mice, while administration of DLT (20 mg/kg) did not further ameliorate PIPN-like symptoms. We demonstrated that DLT administration alleviated dorsal root ganglion neuronal damage and suppressed sciatic nerve destruction, spinal neuron apoptosis and neuroinflammation in the spinal cord of PIPN mice. Furthermore, we revealed that DLT administration suppressed astrocytic neuroinflammation via the 5HTR2A/c-Fos/NLRP3 pathway and blocked astrocyte-neuron crosstalk by targeting 5HTR2A. We conclude that spinal 5HTR2A inhibition holds promise as a therapeutic approach for PIPN and we emphasize the potential of DLT as a dual-functional agent in ameliorating PTX-induced both PIPN and HSR in chemotherapy. In summary, we determined that spinal 5HTR2A was selectively activated in PIPN mice and DLT could ameliorate the PTX-induced both PIPN- and HSR-like pathologies in mice. DLT alleviated the damages of DRG neurons and sciatic nerves, while restrained spinal neuronal apoptosis and CGRP release in PIPN mice. The underlying mechanisms were intensively investigated by assay against the PIPN mice with 5HTR2A-specific knockdown in the spinal cord by injection of adeno-associated virus 9 (AAV9)-5Htr2a-shRNA. DLT inhibited astrocytic NLRP3 inflammasome activation-mediated spinal neuronal damage through 5HTR2A/c-FOS pathway. Our findings have supported that spinal 5HTR2A inhibition shows promise as a therapeutic strategy for PIPN and highlighted the potential advantage of DLT as a dual-functional agent in preventing against PTX-induced both PIPN and HSR effects in anticancer chemotherapy.

Desloratadine alleviates ALS-like pathology in hSOD1G93A mice via targeting 5HTR2A on activated spinal astrocytes.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with progressive loss of motor neurons in the spinal cord, cerebral cortex and brain stem. ALS is characterized by gradual muscle atrophy and dyskinesia. The limited knowledge on the pathology of ALS has impeded the development of therapeutics for the disease. Previous studies have shown that autophagy and astrocyte-mediated neuroinflammation are involved in the pathogenesis of ALS, while 5HTR2A participates in the early stage of astrocyte activation, and 5HTR2A antagonism may suppress astrocyte activation. In this study, we evaluated the therapeutic effects of desloratadine (DLT), a selective 5HTR2A antagonist, in human SOD1G93A (hSOD1G93A) ALS model mice, and elucidated the underlying mechanisms. HSOD1G93A mice were administered DLT (20 mg·kg-1·d-1, i.g.) from the age of 8 weeks for 10 weeks or until death. ALS onset time and lifespan were determined using rotarod and righting reflex tests, respectively. We found that astrocyte activation accompanying with serotonin receptor 2 A (5HTR2A) upregulation in the spinal cord was tightly associated with ALS-like pathology, which was effectively attenuated by DLT administration. We showed that DLT administration significantly delayed ALS symptom onset time, prolonged lifespan and ameliorated movement disorders, gastrocnemius injury and spinal motor neuronal loss in hSOD1G93A mice. Spinal cord-specific knockdown of 5HTR2A by intrathecal injection of adeno-associated virus9 (AAV9)-si-5Htr2a also ameliorated ALS pathology in hSOD1G93A mice, and occluded the therapeutic effects of DLT administration. Furthermore, we demonstrated that DLT administration promoted autophagy to reduce mutant hSOD1 levels through 5HTR2A/cAMP/AMPK pathway, suppressed oxidative stress through 5HTR2A/cAMP/AMPK/Nrf2-HO-1/NQO-1 pathway, and inhibited astrocyte neuroinflammation through 5HTR2A/cAMP/AMPK/NF-κB/NLRP3 pathway in the spinal cord of hSOD1G93A mice. In summary, 5HTR2A antagonism shows promise as a therapeutic strategy for ALS, highlighting the potential of DLT in the treatment of the disease. DLT as a 5HTR2A antagonist effectively promoted autophagy to reduce mutant hSOD1 level through 5HTR2A/cAMP/AMPK pathway, suppressed oxidative stress through 5HTR2A/cAMP/AMPK/Nrf2-HO-1/NQO-1 pathway, and inhibited astrocytic neuroinflammation through 5HTR2A/cAMP/AMPK/NF-κB/NLRP3 pathway in the spinal cord of hSOD1G93A mice.

P19-derived neuronal cells express H1, H2, and H3 histamine receptors: a biopharmaceutical approach to evaluate antihistamine agents.

Histamine is a biogenic amine implicated in various biological and pathological processes. Convenient cellular models are needed to screen and develop new antihistamine agents. This report aimed to characterize the response of neurons differentiated from mouse P19 embryonal carcinoma cells to histamine treatment, and to investigate the modulation of this response by antihistamine drugs, vegetal diamine oxidase, and catalase. The exposure of P19 neurons to histamine reduced cell viability to 65% maximally. This effect involves specific histamine receptors, since it was prevented by treatment with desloratadine and cimetidine, respectively, H1 and H2 antagonists, but not by the H3 antagonist ciproxifan. RT-PCR analysis showed that P19 neurons express H1 and H2 receptors, and the H3 receptor, although it seemed not involved in the histamine effect on these cells. The H4 receptor was not expressed. H1 and H2 antagonists as well as vegetal diamine oxidase diminished the intracellular Ca2+ mobilization triggered by histamine. The treatment with vegetal diamine oxidase or catalase protected against mortality and a significant reduction of H2O2 level, generated from the cells under the histamine action, was found upon treatments with desloratadine, cimetidine, vegetal diamine oxidase, or catalase. Overall, the results indicate the expression of functional histamine receptors and open the possibility of using P19 neurons as model system to study the roles of histamine and related drugs in neuronal pathogenesis. This model is less expensive to operate and can be easily implemented by current laboratories of analysis and by Contract Research Organizations.

Green micellar stability-indicating high-performance liquid chromatography method for determination of rupatadine fumarate in the presence of its main impurity desloratadine: Oxidative degradation kinetics study.

A green micellar stability-indicating high-performance liquid chromatography method was developed for rupatadine fumarate determination in existence with its main impurity desloratadine. Separation was attained using Hypersil ODS column (150 × 4.6 mm, 5 µm), the micellar mobile phase consisted of 0.13 M sodium dodecyl sulfate, 0.1 M disodium hydrogen phosphate adjusted by phosphoric acid to pH 2.8 and 10% n-butanol. The column was maintained at 45◦ C and detection was carried out at 267 nm. A linear response was achieved over the range of 2-160 µg/ml for rupatadine and 0.4-8 µg/ml for desloratadine. The method was applied for rupatadine determination in alergoliber tablets and alergoliber syrup without the interference of methyl paraben and propyl paraben present as main excipients. Rupatadine fumarate revealed pronounced susceptibility to oxidation; further study of oxidative degradation kinetics was carried out. Rupatadine was found to follow pseudo-first-order kinetics when exposed to 10% H2 O2 at 60 and 80°C and the activation energy was found to be 15.69 Kcal/mol. At a lower temperature (40°C), degradation kinetics regression was best fitted as a polynomial quadratic relationship, thus rupatadine oxidation at a lower temperature tends to adopt a second-order kinetics rate. Oxidative degradation product structure was revealed using infrared and found to be rupatadine N-oxide at all temperature values.

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.

Comparison of aprepitant versus desloratadine for EGFR-TKI-induced pruritus: A randomized phase 2 clinical trial.

BACKGROUND: Pruritus is one of the most common and challenging side effects of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) and has impaired patients' quality of life and treatment compliance. Our study evaluated the efficacy and safety of aprepitant in managing EGFR-TKIs-related pruritus. METHODS: This randomized, double-blind, placebo-controlled study was conducted between December 2016 and August 2020 in China. Patients were eligible if they were 18 years or older and had histologically confirmed locally advanced or metastatic non-small cell lung cancer (NSCLC) with first onset of moderate to severe pruritus during EGFR-TKI treatment. RESULTS: A total of 130 eligible patients were randomly assigned to aprepitant (n = 65) or desloratadine (n = 65) groups. The median (interquartile range [Q1, Q3]) age was 63 (54, 70) years, and 79 (60.8%) were women. Mean visual analog scale scores at baseline were 6.35 (95% confidence interval [CI], 5.89-6.82) in the aprepitant group and 5.94 (95% CI, 5.56-6.32) in the desloratadine group. After 1 week of treatment, 33 (53.2%) patients responded to aprepitant, which was significantly higher than that of 14 (23.7%) patients responded to desloratadine (p = .001). Moreover, patients in the aprepitant group had a significantly shorter response time than patients in the desloratadine group (mean [days], 13.39 [95% CI, 11.08-15.70] vs. 16.67 [95% CI, 14.19-19.13], p = .04). The most frequent drug-related adverse events in aprepitant group and desloratadine were constipation and dry mouth, and all adverse events were grade 1-2. CONCLUSIONS: To the authors' knowledge, this is the first study to prospectively present that aprepitant elicited a better and faster response and mild toxicity for managing EGFR-TKI induced pruritus than desloratadine. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02646020.

Molecular Origin of the Distinct Tabletability of Loratadine and Desloratadine: Role of the Bonding Area - Bonding Strength Interplay.

PURPOSE: To explain the different tabletability of two structurally similar H1-receptor antihistamine drugs, loratadine (LOR) and desloratadine (DES), based on the molecular basis of bonding area and bonding strength. METHODS: LOR and DES were characterized by powder X-ray diffractometry, thermal analysis, and dynamic water sorption. The compressibility, tabletability, compactibility, and Heckel analysis of their bulk powders and formulations were evaluated. A combined energy framework and topological analysis was used to characterize the crystal structure - mechanical property relationship. Surface energy of bulk powder was assessed by contact angle measurement using the Owens/Wendt theory. RESULTS: Both LOR and DES bulk powders are phase pure and stable under compaction. The superior tabletability of LOR is attributed to both larger bonding area (BA) and higher interparticle bonding strength (BS). The larger BA of LOR results from its experimentally established higher plasticity, which is explained by the presence of more densely packed molecular layers with smooth surface topology. The higher BS of LOR corresponded to its significantly higher dispersive component of the surface energy. CONCLUSIONS: This work provides new insights into the molecular origins of BA and BS, which can be applied to improve mechanical properties and tableting performance of drugs through appropriate crystal engineering.

Effects of oral desloratadine citrate disodium combined with physiological seawater nasal irrigation on IgE levels, IL-4, IL-6, IL-13 and IFN-γ expression and treatment of intermittent allergic rhinitis.

This experiment was performed to explore the effect of oral desloratadine citrate disodium combined with physiological seawater nasal irrigation in the treatment of intermittent allergic rhinitis and its effect on serum inflammatory factors and peripheral blood Th1 and Th2. For this purpose, 100 patients of intermittent allergic rhinitis admitted to our hospital from January 2018 to January 2020. Randomly divided into a control group (n=50) and an observation group (n=50). The control group was given oral desloratadine citrate disodium. The observation group was given physiological seawater nasal irrigation based on the control group. Both groups were treated for one month. Compare the effect of treatment, symptom and sign scores pre and posttreatment, serum immunoglobulin E (IgE) levels, serum interleukin 4 (IL-4), IL-6, IL-13 and interferon-gamma (IFN-γ) levels, peripheral blood helper T cells 1 (Th1) and Th2 and the recurrence rate of patients after 1 year between two groups. Results showed that after one month of continuous treatment, the total effective rate of the observation group was significantly higher than that of the control group (P <0.05). The symptoms and signs scores and serum IgE levels of the two groups pretreatment (before treatment) were not significantly different (P > 0.05). The symptoms and signs scores and serum IgE levels of the two groups decreased significantly posttreatment (after treatment) (P <0.05), and the observation group was significantly lower than the control group (P <0.05). Pretreatment, the levels of serum inflammatory factors (IL-4, IL-6, IL-13, and IFN-γ) and the ratio of peripheral blood Th1 and Th2 to CD4+T cells were not significantly different (P> 0.05). After one month of continuous treatment, the levels of serum IL-4, IL-6, IL-13, and the ratio of peripheral blood CD4+IL-4+/CD4+ in the observation group and the control group were significantly reduced and the ratio of CD4+IFN-γ+/CD4+ was significantly increased (P <0.05). Compared with the control group, those changes were more obvious in the observation group (P <0.05). The one-year recurrence rate of the observation group was 4% (2/50), which was significantly lower than that of the control group, which was 20% (10/50). There was a statistical difference between the two groups (P <0.05). It was concluded that oral desloratadine citrate disodium combined with physiological seawater nasal irrigation can effectively improve the symptoms and signs of intermittent allergic rhinitis and reduce the recurrence rate. This may be related to balancing T cell responses, promoting systemic Th1 responses and inhibiting Th2 responses, and down-regulating inflammatory response.

A multivariate quantification of Box-Behnken design assisted method development and validation of dextromethorphan hydrobromide and desloratadine simultaneously by reverse-phase HPLC in in-house syrup formulation.

An innovative high-performance liquid chromatography assay method was developed and validated for quantification of dextromethorphan hydrobromide and desloratadine simultaneously in monophasic liquid formulation by preparing syrup containing 30 mg/5 mL of dextromethorphan hydrobromide and 1.2 mg/mL of desloratadine. The chromatographic severance was executed by gradient solution A and B. The composition of buffer solution A contained 0.05 M monobasic potassium, then 1 mL triethylamine was added to it and the pH was adjusted to 2.3 with orthophosphoric acid. Methanol was used as solution B. The gradient elution was executed with Kromasil C8 (250 mm × 4.6 mm) column having 1.5 mL/min flow rate and 20 µL injection volume with UV-estimation at 254 nm for dextromethorphan hydrobromide and DES. The present research was planned according to Box-Behnken design by utilizing design expert software, using four factors such as column temperature (A), flow rate (B), mobile phase-organic phase (C), and pH (D); correspondingly the selected response variables were resolution between A and B, that is, desloratadine and methyl paraben (Y1), tailing of dextromethorphan hydrobromide (Y2), and tailing of desloratadine (Y3). The parameters such as system suitability, linearity, accuracy, precision, robustness, limit of detection, limit of quantitation, and ruggedness were analyzed to validate the developed method in accordance with current regulatory guidelines.

Metabolism of desloratadine by chimeric TK-NOG mice transplanted with human hepatocytes.

1. Desloratadine is an antiallergic drug with species-dependent metabolic profiles in mice, rats, monkeys and humans. We investigated whether humanized-liver mice could reproduce the reported human-specific in vivo metabolic profile for desloratadine in terms of the formation of 3-hydroxydesloratadine and its O-glucuronide.2. Hepatocytes prepared from humans and humanized-liver mice both preferentially catalyzed the formation of 3-hydroxydesloratadine and its O-glucuronide in vitro.3. After a single oral administration of desloratadine, plasma levels of desloratadine and its metabolites (3-hydroxydesloratadine and its O-glucuronide) in humanized-liver mice were lower and higher, respectively, than those in control mice.4. The amounts of 3-hydroxydesloratadine and its O-glucuronide excreted in humanized-liver mouse feces and urine were higher than those of the control mice, whereas 5- and 6-hydroxydesloratadine formation were predominant in the feces and urine samples from control mice. A significant correlation (r = 0.68) for the dose percentage of urinary and fecal metabolites of desloratadine was only observed between the humanized-liver mice and the reported values for humans.5. These results indicated that urinary 3-hydroxydesloratadine O-glucuronide and fecal desloratadine, 3-hydroxydesloratadine and 5-hydroxydesloratadine were the major excretion pathways of desloratadine in humanized-liver mice, which is reasonably similar to that reported for humans.

Hepatocyte spheroids as a viable in vitro model for recapitulation of complex in vivo metabolism pathways of loratadine in humans.

Accurate prediction of in vivo metabolic pathways in humans can be challenging because in vitro liver matrices may fail to produce certain in vivo metabolites.Rat and human spheroids, generated from cryopreserved hepatocytes in media that contained minimal amount of serum, maintained morphology, viability and cytochrome P450 (CYP) activities for at least a week without media exchange.With spheroid cultures, multiple Phase I and Phase II metabolites were observed in rat and human spheroid cultures that were incubated with loratadine (LOR) for multiple days. Consistent with in vivo observations, 3-hydroxydesloratadine, (3-OH-DL), along with its glucuronide, were observed in human spheroids, but not in rat spheroids. Interestingly, the putative intermediate metabolite leading to 3-OH-DL, DL-N-glucuronide, was observed in incubations with both rat and human spheroids. In conclusion, hepatocyte spheroid were capable of recapitulating the inter-species differences in metabolism between human and rat for LOR, therefore, it may represent a viable model for studying complex metabolic pathways.

The effect of desloratadine on ischemia reperfusion induced oxidative and inflammatory renal injury in rats.

Purpose: To examine the effect of desloratadine on kidney ischemia-reperfusion (I/R) injury in albino Wistar male rats using biochemical and histopathological methods.Methods: The treated with ischemia-reperfusion + 5 mg/kg desloratadine (IRD) group (n-6) was given 5 mg/kg desloratadine by gavage orally, and applied renal ischemia-reperfusion (BIR) group (n-6) and control (SG) group undergoing Sham operation (n-6) rats were given distilled water as solvent one hour before ketamine anesthesia. During the anesthesia period, ischemia was induced for 2 h unilaterally in the left kidney of all rats followed by reperfusion for 6 h. The kidneys of the SG group had sham operation without any intervention.Results: Our biochemical test results showed that malondialdehyde (MDA), nuclear factor kappa (NF-κB), tumor necrosis factor alpha (TNF-α), interleukin one beta (IL-1ß), creatinine, and blood urea nitrogen (BUN) levels were significantly increased in the BIR group compared to the healthy control and IRD groups treated with desloratadine. Histopathological results were revealed tubular dilatation, tubular necrosis, loss of brushy margins, cast formation, and apoptotic bodies in tubular epithelial cells in the BIR group. There were no histopathological findings except for the swelling of tubule epithelial cells and the accumulation of proteinous material in some tubule lumens in renal tissue of desloratadine-treated rats.Conclusions: Experimental results suggested that desloratadine may be useful in the treatment of renal I/R injury.

Prolonged intake of desloratadine: mesenteric lymphatic vessel dysfunction and development of obesity/metabolic syndrome.

This study aimed to establish mechanistic links between the prolonged intake of desloratadine, a common H1 receptor blocker (i.e., antihistamine), and development of obesity and metabolic syndrome. Male Sprague-Dawley rats were treated for 16 wk with desloratadine. We analyzed the dynamics of body weight gain, tissue fat accumulation/density, contractility of isolated mesenteric lymphatic vessels, and levels of blood lipids, glucose, and insulin, together with parameters of liver function. Prolonged intake of desloratadine induced development of an obesity-like phenotype and signs of metabolic syndrome. These alterations in the body included excessive weight gain, increased density of abdominal subcutaneous fat and intracapsular brown fat, high blood triglycerides with an indication of their rerouting toward portal blood, high HDL, high fasting blood glucose with normal fasting and nonfasting insulin levels (insulin resistance), high liver/body weight ratio, and liver steatosis (fatty liver). These changes were associated with dysfunction of mesenteric lymphatic vessels, specifically high lymphatic tone and resistance to flow together with diminished tonic and abolished phasic responses to increases in flow, (i.e., greatly diminished adaptive reserves to respond to postprandial increases in lymph flow). The role of nitric oxide in this flow-dependent adaptation was abolished, with remnants of these responses controlled by lymphatic vessel-derived histamine. Our current data, considered together with reports in the literature, support the notion that millions of the United States population are highly likely affected by underevaluated, lymphatic-related side effects of antihistamines and may develop obesity and metabolic syndrome due to the prolonged intake of this medication. NEW & NOTEWORTHY Prolonged intake of desloratadine induced development of obesity and metabolic syndrome associated with dysfunction of mesenteric lymphatic vessels, high lymphatic tone, and resistance to flow together with greatly diminished adaptive reserves to respond to postprandial increases in lymph flow. Data support the notion that millions of the USA population are highly likely affected by underevaluated, lymphatic-related side effects of antihistamines and may develop obesity and metabolic syndrome due to the prolonged intake of this medication.

Efficacy of Desloratadine and Levocetirizine in Patients with Cedar Pollen-Induced Allergic Rhinitis: A Randomized, Double-Blind Study.

BACKGROUND: No comparative study of antihistamines that differ in structural system has been conducted in allergic rhinitis. OBJECTIVE: This was a randomized, double-blind, crossover comparative study to verify the efficacy of antihistamines that differ in structural system. METHODS: A total of 50 patients with moderate or more severe Japanese cedar pollen-induced allergic rhinitis were randomized to receive either placebo, desloratadine 5 mg (a tricyclic), or levocetirizine 5 mg (a piperazine). One dose of the study drug was orally administered at 9 pm on the day before a pollen exposure test, which was performed for 3 h (9 a.m. to 12 p.m.) to assess symptoms in an environmental challenge chamber (ECC). Nasal and ocular symptoms were compared at an airborne pollen level of 8,000 grains/m3. The primary endpoint was mean total nasal symptom score (TNSS) from 120 to 180 min in the ECC. Subjects with a difference of ≥1 in TNSS between 2 drugs were extracted to the relevant drug-responsive group. RESULTS: The difference in TNSS from placebo was -2.42 (p < 0.0001) with levocetirizine and -1.66 (p < 0.01) with desloratadine, showing that both drugs were significantly more effective than placebo in controlling symptoms, but with no statistically significant difference between the 2 drugs. There were 12 subjects in the desloratadine-responsive group and 24 subjects in the levocetirizine-responsive group, with no contributor to response was detected. CONCLUSION: Levocetirizine tended to control nasal symptoms more effectively than desloratadine. However, the response to each antihistamine varied among individuals and the predictors to the response are unknown. CLINICAL TRIAL REGISTRATION NUMBER: UMIN ID: UMIN000029653.

Design, synthesis and biological evaluation of novel desloratadine derivatives with anti-inflammatory and H1 antagonize activities.

To improve the anti-inflammatory activity of desloratadine, we designed and synthesized a series of novel desloratadine derivatives. All compounds were evaluated for their anti-inflammatory and H1 antagonistic activities. Among them, compound 2c showed the strongest H1 antagonistic and anti-inflammatory activity. It also exhibited promising pharmacokinetic profiles and low toxicity. All these results suggest that compound 2c as a novel anti-allergic agent is worthy of further investigation.

Design, synthesis and bioevaluation of tricyclic fused ring system as dual binding site acetylcholinesterase inhibitors.

Due to recently discovered non-classical acetylcholinesterase (AChE) function, dual binding-site AChE inhibitors have acquired a paramount attention of drug designing researchers. The unique structural arrangements of AChE peripheral anionic site (PAS) and catalytic site (CAS) joined by a narrow gorge, prompted us to design the inhibitors that can interact with dual binding sites of AChE. Eighteen homo- and heterodimers of desloratadine and carbazole (already available tricyclic building blocks) were synthesized and tested for their inhibition potential against electric eel acetylcholinesterase (eeAChE) and equine serum butyrylcholinesterase (eqBChE). We identified a six-carbon tether heterodimer of desloratadine and indanedione based tricyclic dihydropyrimidine (4c) as potent and selective inhibitor of eeAChE with IC50 value of 0.09 ±â€¯0.003 µM and 1.04 ±â€¯0.08 µM (for eqBChE) with selectivity index of 11.1. Binding pose analysis of potent inhibitors suggest that tricyclic ring is well accommodated into the AChE active site through hydrophobic interactions with Trp84 and Trp279. The indanone ring of most active heterodimer 4b is stabilized into the bottom of the gorge and forms hydrogen bonding interactions with the important catalytic triad residue Ser200.

Ecotoxic effects of loratadine and its metabolic and light-induced derivatives.

Loratadine and desloratadine are second-generation antihistaminic drugs. Because of human administration, they are continuously released via excreta into wastewater treatment plants and occur in surface waters as residues and transformation products (TPs). Loratadine and desloratadine residues have been found at very low concentrations (ng/L) in the aquatic environment but their toxic effects are still not well known. Both drugs are light-sensitive even under environmentally simulated conditions and some of the photoproducts have been isolated and characterized. The aim of the present study was to investigate the acute and chronic ecotoxicity of loratadine, desloratadine and their light-induced transformation products in organisms of the aquatic trophic chain. Bioassays were performed in the alga Pseudokirchneriella subcapitata, the rotifer Brachionus calyciflorus and in two crustaceans, Thamnocephalus platyurus and Ceriodaphnia dubia. Loratadine exerted its acute and chronic toxicity especially on Ceriodaphnia dubia (LC50: 600 µg/L, EC50: 28.14 µg/L) while desloratadine showed similar acute toxicity among the organisms tested and it was the most chronically effective compound in Ceriodaphnia dubia and Pseudokirchneriella subcapitata. Generally, transformation products were less active in both acute and chronic assays.

[Meta-analysis of efficacy and safety of Tripterygium Glycosides Tablets combined with desloratadine in treatment of chronic urticarial].

To analyze the efficacy and safety of Tripterygium Glycosides Tablets combined with desloratadine as well as desloratadine alone in the treatment of chronic urticaria by Meta-analysis,in order to provide evidence-based reference for clinical treatment.PubMed,CBM,Wan Fang,VIP database and CNKI database were retrieved to collect randomized controlled trials( RCT) about Tripterygium Glycosides Tablets combined with desloratadine( test group) as well as desloratadine alone( control group) in the treatment of chronic urticaria. Meta-analysis was performed by using Rev Man 5. 3 software after data extraction and quality evaluation( a total of 15 RCTs were included,involving 1 411 patients). Meta-analysis showed that the total effective rate( RR = 1. 28,95%CI[1. 22,1. 35],P<0. 000 01) and the quality of life improvement rate( RR = 1. 49,95% CI[1. 33,1. 66],P< 0. 000 01) of the test group were better than those of the control group,and the recurrence rate( RR = 0. 29,95%CI[0. 21,0. 40],P<0. 000 01) was significantly lower than that of the control group,with statistically significant differences; there was no statistically significant difference in the incidence of adverse reactions( RR = 1. 02,95%CI[0. 68,1. 53],P = 0. 92) compared with the control group. Based on the included RCTs,the efficacy of Tripterygium Glycosides Tablets combined with desloratadine in the treatment of chronic urticaria were superior to those of desloratadine alone,with similarity in safety. However,due to the low quality of RCTs and the lack of large-scale multi-center studies,the results shall not be further verified by clinical trials.

Effects of Rupatadine on Platelet- Activating Factor-Induced Human Mast Cell Degranulation Compared With Desloratadine and Levocetirizine (The MASPAF Study).

BACKGROUND AND OBJECTIVE: Platelet-activating factor (PAF) is a lipid mediator involved in the pathophysiology of several allergic diseases, for example, in the amplification of mast cell (MC) activation in anaphylaxis. Rupatadine is an antihistamine with a demonstrated anti-PAF effect, although its capacity to inhibit PAF-induced MC degranulation has not been fully evaluated. Objectives: To compare the ability of rupatadine to inhibit PAF-induced MC degranulation with that of desloratadine and levocetirizine and to confirm the dual anti-H1 and anti-PAF activity of rupatadine. METHODS: The human MC line LAD2 and primary MCs (human lung tissue MCs [hLMCs]) were used. MC mediator release was evaluated using the b-hexosaminidase and histamine release assay. The effects of rupatadine (H1 antagonist + PAF receptor antagonist), desloratadine, and levocetirizine (H1 antagonists) on LAD2 and hLMCs were compared. The PAF receptor antagonists WEB2086, BN52021, and CV6209 were also tested. PAF receptor protein expression was evaluated in both LAD2 and hLMCs. RESULTS: CV6209 and rupatadine inhibited PAF-induced MC degranulation in both LAD2 and hLMCs. In LAD2, rupatadine (5 and 10 µM) and levocetirizine (5 µM), but not desloratadine, inhibited PAF-induced b-hexosaminidase release. Rupatadine (1-10 µM), levocetirizine (1-10 µM), and desloratadine (10 µM) inhibited PAF-induced histamine release. Rupatadine at 10 µM had an inhibitory effect on hLMC degranulation, but levocetirizine and desloratadine did not. CONCLUSIONS: This study shows that rupatadine and, to a lesser extent, levocetirizine, but not desloratadine, inhibit PAF-induced degranulation in both LAD2 and hLMCs. These findings support the dual antihistamine and anti-PAF effect of rupatadine in allergic disorders.