A novel anti-inflammatory treatment for bradykinin-induced sore throat or pharyngitis

Throat spray formulated with virucidal pharmaceutical excipients as an effective early prophylactic or treatment strategy against pharyngitis post-exposure to SARS-CoV-2

Our study aimed to develop a virucidal throat spray using bioactive compounds and excipients, focusing on the preparation of Curcumin (CUR) in a self-nano emulsifying drug delivery system (SNEDDS). Two molecular docking studies against SARS-CoV-2 targets guided the selection of proper oil, surfactant, co-surfactant, and natural bioactive that would maximize the antiviral activity of the throat spray. Two self-nanoemulsifying formulas that were diluted with different vehicles to prepare eight CUR-loaded SNESNS (self-nanoemulsifying self-nanosuspension) formulas. In vitro characterization studies and in vitro anti-SARS-CoV-2 effect revealed that the optimal formula, consisted of 20 % Anise oil, 70 % Tween 80, 10 % PEG 400, and 0.1 %w/w CUR, diluted with DEAE-Dx. Preclinical toxicity tests on male rats confirmed the safety of a mild throat spray dose (5 µg/mL CUR). In a rat model of acute pharyngitis induced by ammonia, post-treatment with the optimal formula of CUR loaded SNESNS for one week significantly reduced elevated proinflammatory markers (TNF-α, IL6, MCP1, and IL8). In conclusion, our CUR-loaded SNESNS formula, at 5 µg/mL concentration, shows promising effect as a prophylactic throat spray against SARS-CoV-2 and as a treatment for pharyngitis.

Monitoring of salicylic acid content in human saliva and its relationship with plasma concentrations

Aspirin is a widely used anti-inflammatory drug. It is reported that a relationship may exist between salicylic acid content in plasma and saliva after taking aspirin. This study established a rapid, convenient, and safe method to assess salicylic acid concentration in human saliva. A novel HPLC-ultraviolet detector was used to measure salicylic acid concentrations in human saliva and plasma. A C18 reversed-phase column with an aqueous solution of 0.1% trifluoroacetic acid (TFA)-acetonitrile mobile phase was used, and drug peaks were recorded at 303 nm. Salicylic acid was completely separated in saliva and plasma. Excellent linearity and correlation (r² ≥ 0.9999) was observed between 0.1 and 2.0 μg/mL. The detection limit (S/N = 3) was 33 ng/mL, and intra- and inter-day recoveries were 103.5-113.3% and 101.1-109.5%, respectively. Salicylic acid was measured within nine hours after administration of acetylsalicylic acid tablets. A positive correlation between salicylic acid content in saliva and plasma was found (r = 0.867, p < 0.001). The proposed method was used successfully to measure salicylic acid concentration in human saliva. Meanwhile, we explored the relationship between salicylic acid levels in plasma and saliva. Saliva might replace blood for monitoring aspirin treatment. In addition, the research provides a reference for application to saliva samples.