Simultaneous Determination of 6 Antiallergic Components in Asarum sieboldii Using High-Performance Liquid Chromatography

Owing to the side effects of current drugs for treating atopic dermatitis (AD), a chronic disease in the skin, traditional herbal medicine is receiving much attention as an alternative treatment. Asarum sieboldii has traditionally been used to treat colds, fevers, headaches, coughs, neuralgia, chronic bronchitis, asthma, and allergies. In this study, 6 compounds (echinacoside, vanillic acid, kakuol, methyl eugenol, sesamin, and asarinin) in A. sieboldii were analyzed simultaneously using high-performance liquid chromatography (HPLC), and the proposed analytical method was validated. In addition, the inhibitory effects of the A. sieboldii extract and the 6 analyzed compounds on the expression of chemokine were evaluated in HaCaT cells. The HPLC method showed high linearity, with a correlation coefficient of ≥0.9999. The limits of detection for the 6 compounds ranged from 0.00 to 0.02 µg/mL, and the limits of quantification ranged from 0.01 to 0.05 µg/mL. The intraday and interday precisions were 0.15%-1.90%; the accuracy was 97.36%-103.23%, and the recoveries of the 6 compounds were 97.45%-103.93%. The content of each compound in A. sieboldii, as determined using the corresponding calibration curve, was in the range of 0.380-12.062 mg/g. This optimized simultaneous quantification method will be suitable for improving the quality control of A. sieboldii. Moreover, the 6 compounds in A. sieboldii showed an inhibitory effect on the production of chemokines, which suggests that A. sieboldii has an antiallergic effect.

Possible Mechanism of Action of the Antiallergic Effect of an Aqueous Extract of Heliotropium indicum L. in Ovalbumin-Induced Allergic Conjunctivitis

Heliotropium indicum is used traditionally as a remedy for conjunctivitis in Ghana. This study therefore evaluated the antiallergic potential of an aqueous whole plant extract of Heliotropium indicum (HIE) in ovalbumin-induced allergic conjunctivitis and attempted to predict its mode of action. Clinical scores for allergic conjunctivitis induced by intraperitoneal ovalbumin sensitization (100 : 10 μg OVA/Al(OH)3 in phosphate-buffered saline [PBS]) and topical conjunctival challenge (1.5 mg OVA in 10 μL PBS) in Dunkin-Hartley guinea pigs were estimated after a week’s daily treatment with 30–300 mg kg−1 HIE, 30 mg kg−1 prednisolone, 10 mg kg−1 chlorpheniramine, or 10 mL kg−1 PBS. Ovalbumin-specific IgG and IgE and total IgE in serum were estimated using Enzyme-Linked Immunosorbent Assay. Histopathological assessment of the exenterated conjunctivae was also performed. The 30 and 300 mg kg−1 HIE treatment resulted in a significantly (p≤0.001) low clinical score of allergic conjunctivitis. Ovalbumin-specific IgG and IgE as well as total serum IgE also decreased significantly (p≤0.01–0.001). The conjunctival tissue in HIE treated guinea pigs had mild mononuclear infiltration compared to the PBS-treated ones, which had intense conjunctival tissue inflammatory infiltration. HIE exhibited antiallergic effect possibly by immunomodulation or immunosuppression.