Sublingual nucleotides and immune response to exercise.

Evidence exists regarding the potential role of exogenous nucleotides as regulators of the immune function in physically active humans, yet the potential use of nucleotides has been hindered by their low bioavailability after oral administration. We conducted a double-blind, placebo-controlled, randomized trial to assess the effect of sublingual nucleotides (50 mg/day) on salivary and serum immunity indicators as compared to placebo, both administered to healthy males aged 20 to 25 years for 14 days. Sublingual administration of nucleotides for 14 days increased serum immunoglobulin A, natural killer cells count and cytotoxic activity, and offset the post-exercise drop of salivary immunoglobulins and lactoferrin (P < 0.05), with no adverse effects reported. No significant differences in fasting salivary antimicrobal proteins (α-amylase, lysozyme and lactoferrin) were found before or after the treatment (P > 0.05). It seems that sublingual administration of nucleotides for two weeks considerably affected immune function in healthy males.