Metabolite profiling and mechanisms of bioactivity of snake autolysate - A traditional Uzbek medicine

Ethnopharmacological relevance: Aqueous autolysate from the snake Eryx miliaris (SNA) has been used in traditional medicine of Uzbekistan as anti-inflammatory, hepatoprotective and immunomodulatory agent. However, little is known about the chemical composition and its mechanisms of activity. Aim of the study: This is our first attempt to analyse the composition of snake autolysate using gas chromatography with mass spectrometry (GC-MS) and to investigate the mechanisms of anti-inflammatory and hyaluronidase activity of fingerprinted E. miliaris autolysate to support their use in the traditional Uzbek medicine. Materials and methods: Aqueous autolysate was evaporated and derivatised for GC-MS analysis of metabolites. For quantification, lipids were extracted from autolysate by solvent extraction and derivatised by esterification and silylation. Biological activity was evaluated with lipid peroxidation, cyclooxygenase (COX) inhibition and antihyaluronidase activity tests. Results: GC-MS analysis of SNA enabled the identification of 27 compounds. Short chain fatty acids (SCFA, 21%), amino acid/derivatives 39% (incl. 2-piperidinone 19%), phenyl (7%), and OH-Phenyl (10%) derivatives covered 77%. Other derivatives (9%) included succinic acid and 3-indole acetic acid). Long chain fatty acids (C₁₆–C₁₈) accounted for 3%. The lipid concentration of SNA was 1.2 mg/mL (0.12%). Three concentration levels (1.0–20.0 μg/mL) did not inhibit COX-1 and COX-2 in vitro and malondialdehyde level was not decreased by SNA in lipid peroxidation model. However, SNA was a potent inhibitor of the hyaluronidase enzyme activity in a dose dependent manner with IC₅₀ = 0.086 mL/mL. Conclusion: The results from GC-MS analyses of SNA lead us to the identification of a wide range of major chemical structures of the metabolites and their derivatives with several categories. Pharmacological studies support the traditional use of SNA and show one of its possible mechanisms of activity via inhibition of hyaluronidase.