Effects of a Dimethyl Sulphoxide-Solubilised Extract of Edible Birds Nest on Salivary Flow Rates

Objectives: To establish the effect on salivary flow rates of two concentrations of an EBN preparation administered three times per week by intraperitoneal injections to 25 week old mice.
Methods: An extract of EBN was prepared as described by Yew, Koh, Chye, Othman and Ng, 2014, yielding a stock solution in Dimethyl Sulphoxide (DMSO). Thirty five female mice type C57BL/6NCl were divided into three groups and pilocarpine-stimulated salivary flow rates determined weekly for five weeks. Group 1 (control, N=12) were injected three times per week with a 0.2% solution of DMSO in normal saline. Group 2 (5 mg EBN extract, N=11) and Group 3 (1 mg EBN extract, N=12) had EBN extract added to each 0.2% DMSO-saline injection as shown. Statistical analysis was by independent t-tests and by ANOVAs to detect differences between the control group versus Groups 2 and 3 using combined data from weeks 2, 3, 4 and 5.
Results: Marked falls of mean initial flow rates of all groups occurred at the end of week 2 and persisted during treatment. Average percentage falls combining weeks 2, 3, 4 and 5 were Group 1, 32.2%, Group 2, 22.9% and Group 3, 27.9%. ANOVAs of the control group versus Groups 2 and 3 from weeks 2, 3, 4 and 5 gave P values of 0.051 and 0.371 respectively.

Conclusions: The closeness of P to statistical significance for the differences in flow rates of the control group and Group 2 (1mg EBN extract per injection) suggests further investigations are needed to determine if a dose-dependent enhancer of salivation of adult mice is present in EBN.