Combining dipyridamole and cilostazol with up-dosing antihistamines improves outcomes in chronic spontaneous urticaria with high D-dimer levels: A randomized controlled trial.

In a double-blind, randomized controlled trial, we investigated the effectiveness of adding antiplatelet drugs to up-dosing antihistamines for the treatment of chronic spontaneous urticaria (CSU) in patients with elevated D-dimer levels who had an inadequate response to conventional antihistamine doses. Twenty patients with Urticaria Activity Score over 7 days (UAS7) ≥16 and D-dimer >500 ng/mL were randomized to receive either antiplatelet therapy (cilostazol 150 mg/day + dipyridamole 50 mg/day) with antihistamine (desloratadine 20 mg/day) or antihistamine alone for 4 weeks. The antiplatelet group demonstrated a greater decrease in UAS7 compared to the control group (28.10 to 8.90 vs. 22.90 to 16.40, p < 0.001 vs. p = 0.054). Both groups experienced improved quality of life (DLQI), but the improvement was greater in the antiplatelet group (p = 0.046). D-dimer levels decreased only in the antiplatelet group (1133.67 ng/mL to 581.89 ng/mL, p = 0.013) with no significant change observed in the control group. This suggests that combining dipyridamole and cilostazol with up-dosing antihistamines may be more effective for CSU patients with high D-dimer levels compared to up-dosing antihistamines alone. This could be due to a reduction in platelet activation, as evidenced by the decrease in D-dimer levels observed in the antiplatelet group.

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 via its anti-inflammatory and antioxidative properties ameliorates TNBS-induced experimental colitis in rats.

BACKGROUND: Intestinal mucosal immune cells, notably mast cells, are pivotal in ulcerative colitis (UC) pathophysiology. Its activation elevates tissue concentrations of histamine. Inhibiting colonic histamine release could be an effective therapeutic strategy for treating UC. Experimental model like 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats mimic human IBD, aiding treatment investigations. Drug repurposing is a promising strategy to explore new indications for established drugs. Desloratadine (DES) is second-generation antihistamine utilized for managing allergies by blocking histamine action in the body. It also has reported anti-inflammatory and antioxidant actions. OBJECTIVE: DES was investigated for its repurposing potential in UC by preclinical screening in TNBS-induced colitis in Wistar rats. METHODS: Therapeutic efficacy of DES was evaluated both individually and in combination with standard drug 5-aminosalicylicacid (5-ASA). Rats were orally administered DES (10 mg/kg), 5-ASA (25 mg/kg), and DES + 5-ASA (5 mg + 12.15 mg) following the induction of colitis. Parameters including disease activity score rate (DASR), colon/body weight ratio (CBWR), colon length, diameter, pH, histological injury, and scoring were evaluated. Inflammatory biomarkers such as IL-1ß, TNF-α, along with reduced glutathione (GSH), and malondialdehyde (MDA) were assessed. RESULTS: Significant protective effects of DES, especially in combination with 5-ASA, against TNBS-induced inflammation were observed as evidenced by reduced DASR, CBWR, and improved colon morphology. Drugs significantly lowered plasma and colon histamine and, cytokines levels. GSH restoration, and decreased MDA content were also observed. CONCLUSION: DES and DES + 5-ASA demonstrated potential in alleviating colonic inflammation associated with TNBS-induced colitis in rats. The effect can be attributed to its antihistamine, anticytokine, and antioxidative properties.

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.

Inoculation of heavy metal resistant bacteria alleviated heavy metal-induced oxidative stress biomarkers in spinach (Spinacia oleracea L.).

Most vegetable crops are severely affected by the uptake of heavy metals from the soil. Heavy metals in vegetable bodies generate reactive oxygen species (ROS) that unbalance the antioxidant defense system. This study was initiated to determine the physiological and biochemical characteristics of spinach plants grown on soil contaminated with heavy metals and responding to Bacillus cereus and Bacillus aerius were isolated from soil contaminated with heavy metals. Heavy metal contamination led to a significant reduction in seed germination, seedling biomass, protein, and total nitrogen content of spinach plants grown in contaminated soils compared to control soils. In contrast, a significant increase in the content of metallothioneins and antioxidant enzymes was observed. Plants inoculated with B. cereus and B. aerius significantly reduced the oxidative stress induced by heavy metals by improving seed germination (%), seedling growth, nitrogen, and protein content. The content of metallothioneins and the activities of antioxidant enzymes were reduced in spinach plants grown from seeds inoculated with bacterial strains. In addition, plants inoculated with, B. cereus and B. aerius showed greater stomata opening than plants grown on soil contaminated with heavy metals, whose stomata were almost closed. These results suggested that both bacterial strains enhanced plant growth by reducing oxidative stress caused by metals.

Oral isotretinoin with desloratadine compared with oral isotretinoin alone in the treatment of moderate to severe acne: a randomized, assessor-blinded study.

BACKGROUND: Our aim was to measure the effectiveness of oral isotretinoin with desloratadine compared with oral isotretinoin alone in treating moderate to severe acne at a tertiary care teaching hospital in North India. In this study, 90 patients with moderate to severe acne were enrolled to participate based on their fulfilling the inclusion criteria. METHODS: A randomized, assessor-blinded, parallel-arm study was conducted. Randomization was done using computer-generated tables to allocate treatments in a 1:1 ratio. A low-dose oral isotretinoin at a dose of 0.3 mg/kg/day with tab desloratadine at 5 mg/day was applied to the study group and compared against the same patients going without the dosage when controls were conducted. Follow-up was at 4, 8, and 12 weeks. RESULTS: The primary outcome was an improved global acne grading system (GAGS) score and decreased acne lesion count. SECONDARY OUTCOME: patient satisfaction with treatment. The 90 participants were randomized and 15 participants dropped out of the study, leaving 75 participants for intention to treat analysis (n = 41, n = 30). At week 12, the GAGS score and acne lesion count between the study and control groups were comparable (P > 0.05). Pruritus reported was 9.76% in the study versus 33.33% in the control group (P = 0.018). Also, 53.66% of participants reported "excellent" treatment satisfaction in the study group versus 36.67% in the control group. CONCLUSIONS: The addition of desloratadine to an isotretinoin regimen has a role in reducing disease and therapy-related pruritus in acne and leads to improved patient satisfaction.

Discovery of the novel and potent histamine H1 receptor antagonists for treatment of allergic diseases.

Desloratadine, a second-generation histamine H1 receptor antagonist, has established itself as a first-line drug for the treatment of allergic diseases. Despite its effectiveness, desloratadine exhibits an antagonistic effect on muscarinic M3 receptor, which can cause side effects such as dry mouth and urinary retention, ultimately limiting its clinical application. Herein, we describe the discovery of compound Ⅲ-4, a novel H1 receptor antagonist with significant H1 receptor antagonistic activity (IC50 = 24.12 nM) and enhanced selectivity towards peripheral H1 receptor. In particular, Ⅲ-4 exhibits reduced M3 receptor inhibitory potency (IC50 > 10,000 nM) and acceptable hERG inhibitory activity (17.6 ± 2.1 µM) compare with desloratadine. Additionally, Ⅲ-4 exhibits favorable pharmacokinetic properties, as well as in vivo efficacy and safety profiles. All of these reveal that Ⅲ-4 has potential to emerge as a novel H1 receptor antagonist for the treatment of allergic diseases. More importantly, the compound Ⅲ-4 (HY-078020) has recently been granted clinical approval.

Maximal medical treatment of adenoid hypertrophy: a prospective study of preschool children.

PURPOSE: This study aimed to examine the effectiveness of the combined maximal medical treatment for adenoid hypertrophy in preschool children. METHODS: Sixty-four children underwent one-year combined therapy with intranasal mometasone furoate, oral desloratadine, nasal saline irrigation, and bacteriotherapy. Additionally, decongestion drops were applied during scheduled breaks. RESULTS: Of the 64 treated children, 72% showed clinical improvement in adenoid symptoms while 28% did not improve and underwent surgery. These groups differed significantly in terms of the overall reduction in ailments after treatment (p < 0.001), infection rate (p < 0.001), catarrh severity (p < 0.001) and nasal patency (p < 0.001). Endoscopic examination confirmed that responders experienced, on average, a decrease of 8.4% in the adenoid/choana ratio and an improvement in mucosal coverage of the adenoid. These effects were not observed in the group of children whose parents opted for surgery after nine months of conservative treatment. CONCLUSIONS: The proposed new schema of long-term maximal medical treatment with the use of combined intermittent treatment of intranasal mometasone furoate and decongestion drops, oral desloratadine, nasal saline irrigation, and bacteriotherapy can be attempted in patients with adenoid hypertrophy symptoms, and responders may avoid the need for surgery. The applied treatment breaks resulted in a low number of therapeutic side effects.

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.

Series of Desloratadine Platinum(IV) Hybrids Displaying Potent Antimetastatic Competence by Inhibiting Epithelial-Mesenchymal Transition and Arousing Immune Response.

Metastasis is the major obstacle to the survival of cancer patients. Herein, a series of new desloratadine platinum(IV) conjugates with promising antiproliferative and antimetastatic activities were developed and evaluated. The candidate complex caused significant DNA damage and stimulated mitochondrial apoptosis through the Bcl-2/Bax/caspase3 pathway. Then, it suppressed the epithelial-mesenchymal transition (EMT) process in tumors effectively through NMT-1/HPCAL1 and ß-catenin signaling. Subsequently, the angiogenesis was inhibited with the downregulation of key proteins HIF-1α, VEGFA, MMP-9, and CD34. Moreover, the antitumor immunity was effectively aroused by the synergism of EMT reversion and decrease of the histamine level; then, the macrophage polarization from M2- to M1-type and the increase of CD4+ and CD8+ T cells were triggered simultaneously in tumors.

Desloratadine citrate combined with compound glycyrrhizin in the treatment of subacute eczema: A randomized trial.

To investigate the efficacy of desloratadine citrate combined with compound glycyrrhizin in the treatment of subacute eczema. 100 patients with subacute eczema who were admitted in our hospital from June 2019 to June 2020 were selected according to the order of admission, and divided into experimental groups (n=50, using a single compound glycyrrhizin) and control group (n=50, using compound glycyrrhizin combined with desloratadine citrate); the curative effect was compared between the two groups. After treatment, the inflammatory factors in the experimental group were lower than those in the control group [TNF-α (ng/L) (35.16±3.31), IL-2 (pg/ml) (24.39±3.11), IL-4 (pg/ml) (39.82± 4.48) vs TNF-α (ng/L) (44.24±3.87), IL-2 (pg/ml) (41.68±3.89), IL-4 (pg/ml) (49.88±5.74)] (P<0.05). After treatment the adverse reaction rate of the experimental group was lower than that of the control group (P<0.05). After treatment,the experimental group yielded higher total effective rate in relative to the control group (P<0.05). Desloratadine citrate plus compound glycyrrhizinfor might be a preferable option for clinical treatment of patients with subacute eczema, with an ideal effectiveness profile.

Effective RNAi in leukemia cells is enhanced by spermine-modified pullulan combined with desloratadine.

RNA interference is a very useful tool for clinical treatment as well as mechanistic studies of leukemia. However, leukemia cells are known as hard-to-transfected by non-virus carriers. The low capacity of endocytosis and lysosomal escape of synthetic carriers are two obstacles for successful RNAi in leukemia cells. In this work, we established a universal powerful strategy for mediating effective RNAi in different types of leukemia cells by sequentially using spermine-modified pullulan (PS) as siRNA carrier and desloratadine (DL) to promote the lysosomal escape. It was shown that the complex of PS and siRNA could be largely internalized by human T-cell acute lymphoblastic leukemia cells, acute myeloid leukemia cells and chronic myeloid leukemia cells in serum-containing media, and the internalized complex was able to escape from the lysosomes by the aid of DL, resulting in effective RNAi against the key genes for the different leukemia cells.

Surveillance of Stability Under Different Stress Conditions in Desloratadine and Study of Degradation Kinetics.

BACKGROUND: A stability-indicating method (SIM) stipulates the testing of the drug product and drug substances under the stressed conditions that will imply a clear notion about the stress conditions that would affect the drug in its finished dosage form. Furthermore, manufactures can clearly define the state at which the drug is unstable and present its storage conditions. OBJECTIVE: The present article deals with the stability testing and degradation kinetic studies of desloratadine (DL). METHOD: The method of analysis was UV visible spectroscopy, which is a most convenient and reliable method for the analyst. A method was developed and validated according to the ICH Q2 guidelines along with the amendment in 2018 (ICH Q14). RESULTS: The study denotes that the drug is extremely unstable in the presence of dry heat and then follows the oxidative and basic degradations. The acidic, neutral, and photolysis did not show notable degradations. CONCLUSIONS: The chemical kinetic studies were carried out to more clearly understand the mechanism of degradation and to present the order of reaction, rate of reaction, and reaction half-time. HIGHLIGHTS: The application of a spectrophotometric method in the development of a SIM and study of degradation kinetics is much handier and cost-effective.

Desloratadine Exposure and Incidence of Seizure: A Nordic Post-authorization Safety Study Using a New-User Cohort Study Design, 2001-2015.

INTRODUCTION: A small number of adverse events of seizure in patients using desloratadine (DL) have been reported. The European Medicines Agency requested a post-authorization safety study to investigate whether there is an association between DL exposure and seizure. OBJECTIVE: The aim was to study the association between DL exposure and incidence of first seizure. METHODS: A new-user cohort study of individuals redeeming a first-ever prescription of DL in Denmark, Finland, Norway, and Sweden in 2001-2015 was conducted. DL exposure was defined as days' supply plus a 4-week grace period. DL unexposed periods were initiated 27 weeks after DL prescription redemption. Poisson regression was used to estimate the adjusted incidence rate and adjusted incidence rate ratio (aIRR) of incident seizure. RESULTS: A total of 1,807,347 first-ever DL users were included in the study, with 49.3% male and a mean age of 29.5 years at inclusion; 20.3% were children aged 0-5 years. The adjusted incidence rates of seizure were 21.7 and 31.6 per 100,000 person-years during DL unexposed and exposed periods, respectively. A 46% increased incidence rate of seizure was found during DL exposed periods (aIRR = 1.46, 95% confidence interval [CI] 1.34-1.59). The aIRR ranged from 1.85 (95% CI 1.65-2.08) in children aged 0-5 years to 1.01 in adults aged 20 years or more (95% CI 0.85-1.19). CONCLUSION: This study found an increased incidence rate of seizure during DL exposed periods as compared to unexposed periods among individuals younger than 20 years. No difference in incidence rate of seizure was observed in adults between DL exposed and unexposed.

Efficiency and safety of desloratadine in combination with compound glycyrrhizin in the treatment of chronic urticaria: a meta-analysis and systematic review of randomised controlled trials.

CONTEXT: Desloratadine, an H1 receptor antagonist, is suggested as an effective first-line drug for chronic urticarial (CU). However, the efficacy of desloratadine alone is limited, and the recurrence rate of CU is relatively high. OBJECTIVE: We sought to evaluate the efficacy and clinical feasibility of desloratadine in combination with compound glycyrrhizin in the treatment of CU. MATERIALS AND METHODS: A systematic literature search was conducted in the databases of the China National Knowledge Infrastructure Database, VIP, WanFang, PubMed, and Web of Science using subject terms: "Chronic urticaria", "Loratadine", and "Compound glycyrrhizin". Randomised controlled trials (RCTs) that compared the efficiency and safety of the combination treatment with desloratadine alone starting from January 1, 2014 until February 10, 2021 were selected by two co-first authors independently, and the extracted data were analysed using Rev Man 5.3 software. RESULTS: Fourteen RCTs were included in our meta-analysis with a total of 1501 patients. The results showed that the combination treatment yielded a better treatment effect (total response rate: RR = 1.23, 95% CI: 1.17 to 1.29, p < 0.00001; cure rate: RR = 1.50, 95% CI: 1.30 to 1.73, p < 0.00001), lower recurrence rate as well as superior immune improvement than the treatment with desloratadine alone. In addition, there was no significant difference in the safety of the two treatments. DISCUSSION AND CONCLUSION: The combination of desloratadine and compound glycyrrhizin is a promising treatment for CU and is associated with decreased serum IgE level and improved proportions of CD4+ T and CD8+ T cells.

Increasing Angiogenesis Factors in Hypoxic Diabetic Wound Conditions by siRNA Delivery: Additive Effect of LbL-Gold Nanocarriers and Desloratadine-Induced Lysosomal Escape.

Impaired wound healing in people with diabetes has multifactorial causes, with insufficient neovascularization being one of the most important. Hypoxia-inducible factor-1 (HIF-1) plays a central role in the hypoxia-induced response by activating angiogenesis factors. As its activity is under precise regulatory control of prolyl-hydroxylase domain 2 (PHD-2), downregulation of PHD-2 by small interfering RNA (siRNA) could stabilize HIF-1α and, therefore, upregulate the expression of pro-angiogenic factors as well. Intracellular delivery of siRNA can be achieved with nanocarriers that must fulfill several requirements, including high stability, low toxicity, and high transfection efficiency. Here, we designed and compared the performance of layer-by-layer self-assembled siRNA-loaded gold nanoparticles with two different outer layers-Chitosan (AuNP@CS) and Poly L-arginine (AuNP@PLA). Although both formulations have exactly the same core, we find that a PLA outer layer improves the endosomal escape of siRNA, and therefore, transfection efficiency, after endocytic uptake in NIH-3T3 cells. Furthermore, we found that endosomal escape of AuNP@PLA could be improved further when cells were additionally treated with desloratadine, thus outperforming commercial reagents such as Lipofectamine® and jetPRIME®. AuNP@PLA in combination with desloratadine was proven to induce PHD-2 silencing in fibroblasts, allowing upregulation of pro-angiogenic pathways. This finding in an in vitro context constitutes a first step towards improving diabetic wound healing with siRNA therapy.

[Drug-induced toxidermia in a patient receiving hydroxychloroquine as systemic therapy for primary Gougerot-Sjögren syndrome: a case report]. / Toxidermie médicamenteuse sous hydroxychloroquine pour traitement systémique d'un syndrome de Gougerot-Sjögren primaire: à propos d'un cas.

We here report the case of a 41-year-old female patient with maculopapular rash occurring a week after receiving hydroxychloroquine 400 mg for primary Gougerot-Sjögren syndrome with articular involvement. The patient had more than 1-year history of idiopathic minimal glomerular lesion, effectively treated with corticosteroid therapy. Maculopapular rashes resolved after hydroxychloroquine treatment was stopped and the patient was given hydrocortisone and desloratadine. Our case highlights the importance of prescribing low dose hydroxychloroquine in subjects with a history of kidney disease as well as of raising awareness and educating patients about side effects of hydroxychloroquine.

Antihistamines Modulate Functional Activity of Macrophages.

We compared the effects of the first-, second- and third-generation antihistamines in different doses on enzyme activity and cytokine production by macrophages and their death using an in vitro model. It was found that decreasing the dose led to an increase in the number of viable cells; after contact with second-generation antihistamines (loratadine, desloratadine), apoptosis of macrophages predominated. A dose-dependent increase in activity of ATPase and 5'-AMP with less pronounced effect of second-generation drugs was revealed. It was shown that under the influence of drugs, macrophages do not produce IL-1ß, but actively synthesize TNFα and IL-10, which indicates the immunomodulatory properties of these drugs.

Testing of the inhibitory effects of loratadine and desloratadine on SARS-CoV-2 spike pseudotyped virus viropexis.

Currently, there is an urgent need to find a treatment for the highly infectious coronavirus disease (COVID-19). However, the development of a new, effective, and safe vaccine or drug often requires years and poses great risks. At this critical stage, there is an advantage in using existing clinically approved drugs to treat COVID-19. In this study, in vitro severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) spike pseudotyped viral infection experiments indicated that histamine H1 antagonists loratadine (LOR) and desloratadine (DES) could prevent entry of the pseudotyped virus into ACE2-overexpressing HEK293T cells and showed that DES was more effective. Further binding experiments using cell membrane chromatography and surface plasmon resonance demonstrated that both antagonists could bind to ACE2 and that the binding affinity of DES was much stronger than that of LOR. Molecular docking results elucidated that LOR and DES could bind to ACE2 on the interface of the SARS-CoV-2-binding area. Additionally, DES could form one hydrogen bond with LYS31 but LOR binding relied on non-hydrogen bonds. To our knowledge, this study is the first to demonstrate the inhibitory effect of LOR and DES on SARS-CoV-2 spike pseudotyped virus viropexis by blocking spike protein-ACE2 interaction. This study may provide a new strategy for finding an effective therapeutic option for COVID-19.

Assessing the effect of prolonged use of desloratadine on adipose Brillouin shift and composition in rats.

Antihistamines, which are commonly used to treat allergic reactions, are known for their side effects, which contribute to weight gain. It is hypothesized that simultaneous Brillouin elastography and Raman spectroscopy can be used to detect changes in adipose tissue associated with a prolonged intake of desloratadine, a commonly used second generation antihistamine. White and brown adipose tissue samples were excised from adult rats following 16 weeks of daily administration of desloratadine. It was found that the prolonged intake of desloratadine leads to an increase in Brillouin shift in both adipose tissue types. Raman spectra indicate that antihistamine use reduces protein-to-lipid ratio in brown adipose tissue but not white adipose tissue, indicating the effect on adipose tissue is location-dependent.