Characterisation of protease activity in extracellular products secreted byGiardia duodenalistrophozoites treated with propolis

Abstract

Results from our laboratory revealed propolis activity on Giardia trophozoites proliferation. Since therapeutic agents can inhibit the activity of proteases related to relevant biologic and physiologic processes of parasites, this study was undertaken to characterise the proteolytic activity of excretory/secretory products (ESP) of trophozoites treated with propolis. ESP was obtained from culture supernatants of trophozoites exposed to 250 and 500 µg mL(-1) of propolis. ESP were tested in sodium dodecyl sulfate-polyacrylamide gel electrophoresis for the protein profiles and the protease activity was assayed in gelatin-containing gels. Synthetic inhibitors were used to characterise the protease classes. Treated and non-treated ESP showed a similar protein and hydrolysis pattern. A simple pattern of protein composed by five evident bands of approximately 167, 132, 79, 61 and 51 kDa was found, and the zymograms comprised hydrolysis zones distributed from >170 to 23 kDa. No inhibition was seen on protease activity of propolis-treated trophozoites, whose hydrolysis pattern was similar to control. One may conclude that both ESP degraded gelatin and the activity was predominantly due to cysteine proteases. Although propolis had no effect on the proteolytic activity, further studies could identify the active constituents responsible for propolis antigiardial activity and their mechanisms of action.

Effect of bee venom or proplis on molecular and parasitological aspects of Schistosoma mansoni infected mice

“…While, Orsi et al (2010) illustrated that Bulgarian proplis preparations showed an important antibacterial action on Salmonella Typhi infection, as well as a synergistic effect with antibiotics action on the ribosome. David et al (2010) studied proplis activity on Giardia trophozoites proliferation and revealed that antigiardial activity of proplis.…”

Effects of Propolis on Infectious Diseases of Medical Relevance

“…Similarly, propolis from Brazil showed efficacy in eliminating trophozoites of G. lamblia . The effect on the proteolytic activity of excretory/secretory products (ESPs) from trophozoites treated with propolis was studied; however, no significant differences were found between hydrolysis patterns and inhibition on the protease activity of propolis-treated and untreated trophozoites [ 160 , 161 ]. Propolis from Egypt was reported to be effective in an in vivo model of giardiasis with immunodeficient mice.…”