en Pharmacology Pharmacology مقاله پژوهشی Original Research Article <p style="text-align: justify;"><span style="font-size:16px;"><span style="font-family:Times New Roman;"><strong new="" roman="" style="font-family: " times=""><span style="color:#ffffff;"><span style="background-color:#16a085;">Background and Objective:</span></span>&nbsp;</strong><span style="line-height:115%">Conventional treatment of Acanthamoeba typically involves a combination drug strategy, but its efficacy in clinical settings remains incomplete. Evaluating the therapeutic potential of existing drugs is a way used to introduce effective treatments for infectious agents. This study aimed to assess the in vitro anti-Acanthamoeba effect of valproate (VPA).</span><br> <strong new="" roman="" style="font-family: " times=""><span style="color:#ffffff;"><span style="background-color:#16a085;">Materials and Methods:</span></span>&nbsp;</strong><span style="line-height:115%">An experimental study was conducted using Acanthamoeba cysts belonging to the T4 and T5 genotypes. Cysts collected from the culture medium were exposed to gentamicin, polymyxin, and three different concentrations of VPA for varying durations (1, 4, 6, and 24 hours). The treated cysts were stained with trypan blue, and the percentage of growth inhibition was calculated. Additionally, the viability of treated cysts was assessed by culturing them on non-nutrient agar plates for one month.</span><br> <strong new="" roman="" style="font-family: " times=""><span style="color:#ffffff;"><span style="background-color:#16a085;">Results:</span></span></strong>&nbsp;<span style="line-height:115%">The Acanthamoeba cysts of T4 and T5 genotypes showed susceptibility to VPA. The minimal cysticidal concentration (MCC) of VPA for maximum growth inhibition in both single and combination drug assays were 100 and 3 mg/ml, for durations of 24 and 4 hours, respectively. The growth inhibition observed in the groups exposed to gentamicin and polymyxin differed significantly from the growth inhibition in the group treated with &ge;100 mg/ml VPA (<i>P</i>< 0.05).</span><br> <strong new="" roman="" style="font-family: " times=""><span style="color:#ffffff;"><span style="background-color:#16a085;">Conclusion:</span></span>&nbsp;</strong><span style="line-height:115%">VPA enhances the effects of gentamicin and polymyxin on Acanthamoeba. Combining a low concentration of VPA (&ge;3 mg/ml) with gentamicin and polymyxin increases the potency and speed of action of these antibiotics.</span></span></span></p> Acanthamoeba, Gentamicin, Polymyxin, Valproate, Single Drug Strategy, Combination Drug Strategy 457 463 http://journal.zums.ac.ir/browse.php?a_code=A-10-5669-2&slc_lang=en&sid=1 Reza Rahimi Reza.rahimi@arakmu.ac.ir 5200319475328460078821 5200319475328460078821 No Dept. of Pharmacology, School of Medicine, Arak University of Medical Sciences, Arak, Iran Reza Hajihossein rhajihossein@gmail.com 5200319475328460078822 5200319475328460078822 No Dept. of Parasitology and Mycology, School of Medicine, Arak University of Medical Sciences, Arak, Iran Zahra Eslamirad dr.eslami@arakmu.ac.ir 5200319475328460078823 5200319475328460078823 Yes Dept. of Parasitology and Mycology, School of Medicine, Arak University of Medical Sciences, Arak, Iran