Schistosomiasis is one of the
world's greatly neglected tropical
diseases, and its control is largely
dependent on a single drug,
praziquantel. Hence the there is a
pressing need to develop novel schistosomicidal
drugs to guard against the
potential hazards of a sole drug dependent
chemotherapy. This study has
investigated the in vitro effect of mefloquine;
an antimalarial aminoalcohol
recently found to have a promising
antischistosomal properties on adult
Schistosoma haematobium worms.
The in vitro effects of mefloquine were
monitored by means of phenotypic
evaluation, death rate variance estimation,
viability score calculation and
scanning electron microscopy(SEM).
Incubation of Schistosoma haematobium
adults with 5,10,25,50,75 and
100 ig/m1 mefloquine for 1, 24 and 48
hours resulted in a wide spectrum of
phenotypic changes ranged from a
minimal altered morphological features
and slightly decreased motor
activities to rapid death of Schistosoma
haematobium accompanied by coiling
or flattening according to the parasite
status at the time of death.The worm
death rate ranged from 0-80% at 1
hour time point,0-100% at 24 hours,
and reached up to 100% for all concentrations
at 48 hours time point.
There was a strong positive correlation
between applied mefloquine concentrations
and schistosomes death
rates at lhour time point.Female
worms death rates were significantly
lower than male ones at lethal concentrations
less than 100 jig/ml. The mean
viability score ranged from 3 down to
0.75 at 1 hour time point, 2 to 0 at 24
hours and reached to 0 ( total worm
death) at 48 hours time point. A strong
negative correlation was found between
applied mefloquine concentrations
and schistosomes viability score
at 1 and 24 hours time points.
SEM study revealed also a mild
to extensive tegumental disruption
such as blebbing, sloughing, and furrowing
and swelling, which is both
dose and time dependent.
This study findings hold promise
for the development of a novel antischistosomal
drug that effectively treat
Schistosoma haematobium and enhance
the potential usage of mefloquine
in treatment of schistosomiasis
haematobium infection in humans |
