Effect of Certain Antibiotics Against Filarial Parasite Brugia malayi In Vitro: Possible Role of Oxidative Stress

Abstract

WHO-Tropical Disease Research scheme highlighted the need for development of new anti-filarial drugs. Certain antibiotics have recently been found effective against Wolbachia, co-existing symbiotically with filarial parasites. Inflammatory response entails oxidative mechanism to educe direct anti-microbial effect. In the present study microfilariae were maintained in vitro in medium supplemented with varying concentrations of tetracycline, doxycycline (20-100 lg/ml) or ciprofloxacin (50-250 lg/ml) separately to find out any involvement of oxidative mechanism in the anti-filarial effect of these antibiotics. Loss of motility of the microfilariae was measured after 48 h and correlated with the levels of MDA, nitric oxide and proteincarbonylation. Significant loss of microfilarial motility was recorded with increasing concentration of tetracycline and doxycycline but with ciprofloxacin the effect was not marked. Agents with high antifilarial activity revealed significant association with oxidative parameters in a dose dependent manner. The result suggests that oxidative effect might be exploited to design novel antifilarial drug candidate.

The symbiotic role of Wolbachia in Onchocercidae and its impact on filariasis

“…Anti-Wolbachia therapy with doxycycline (a semisynthetic derivative of the tetracycline family) has been recommended for the treatment of individuals with lymphatic filariasis and onchocerciasis [8,48,58,84,85,[95][96][97][98][99][100][101][102] (Table 2). It allows the development of filariae in their vector to be blocked, thus arresting the transmission [103,104].…”

Antifilarial activity of Butea monosperma L. leaves extracts against Setaria cervi

“…This antibiotic not showed much more activity as other two extracts used. In similar study Ciprofloxacin was shown antifilarial activity against Brugia malayi parasite [23]. Novobiocin antibiotics also found to be active in many experiment against Brugia malayi [24,25].…”

Susceptibility Testing of Medically Important Parasites

“…Because the Brugia malayi life cycle can be maintained in small mammals, this species is the one used most often for in vitro drug screening studies (132)(133)(134)(135)(136)(137)(138)(139)(140)(141)(142)(143). Other filariae used for in vitro drug testing include Brugia pahangi (153), O. volvulus and other Onchocerca species (141,144), L. loa (145), Litomosoides sigmodontis and Acanthocheilonema viteae (filarial nematodes of rodents) (146)(147)(148), and Setaria species (filarial nematodes of sheep, cattle, and other ruminant mammals) (149)(150)(151)(152).…”

“…For most studies evaluating the effects of potential antifilarial agents, microfilariae are observed on a regular basis for a period of 1 to 7 days, and adult filarial worms are observed for a period of days to weeks (132-136, 138, 140-144, 148, 153). While worms can be identified as simply motile or nonmotile (136,139,140,142,145), in many studies, scoring systems have been applied to characterize the degree of motility observed at different time points (132-135, 138, 143, 144, 148, 151-153).…”