Pre-treatment with the methanol extract of Withania somnifera prevents Diazinon -induced cardiotoxic effects of organophosphate poisoning
Organophosphate poisoning represents a major and growing global health problem especially in the developing countries and cardiotoxicity is the major cause of death. Thus, a compelling need to develop novel low cost efficacious agents to manage this condition. Objective To evaluate the methanol extract of Withania somnifera as a pre-treatment agent in the prevention of the cardiotoxic effects of diazinon in Sprague Dawley rats Materials and Methods Twenty one (21) adult rats were randomized to receive 200 mg/kg methanol extract of Withania somnifera (test group), vehicle (negative control) or 200 [mu]g/kg Neostigmine as pre-treatment 30 minutes prior to the oral administration of 200 mg/kg Diazinon. Baseline and post-treatment electrocardiograms (ECGs) were recorded by the Powerlab data acquisition system (ML865 AD instruments, Sydney, Australia). The experimental data were expressed as median [plusmn] the inter-quartile range and analysed using the Kruskal [minus] Wallis non[minus]parametric test and followed by Mann[minus]Whitney U post hoc test in cases of significance, which was set at p < 0.05. Statistical Package for Social Sciences (SPSS) version 17 software was used for analysis. Results Pre-treatment with the methanol extract of W. somnifera had significant effect on the following diazinon-induced electrocardiographic changes; RR interval (0.026 (0.007 [minus] 0.065) vs. 0.035 (0.019 [minus] 0.050) vs. 0.090 (0.071 [minus] 0.01), p = 0.031),heart rate ([minus]54.235 (115.317 [minus] ([minus]19.857)) vs. [minus]96.136 ([minus]96.472 [minus] ([minus]43.879)) vs. [minus]174.361 ([minus]189.775 [minus] ([minus]129.469)), p = 0.014), PR interval (0.006 (0.004 [minus] 0.008) vs. 0.003 (0.001 [minus] 0.004) vs. 0.009 (0.006 [minus] 0.015), p = 0.019), QRS interval (0.005 (0.001 [minus] 0.008) vs. [minus]0.002 ([minus]0.005 [minus] 0.001) vs. 0.007 (0.003 [minus] 0.011), p = 0.023) and ST height ([minus]34.830 ([minus]63.578 [minus] 4.215) vs. [minus]22.330 ([minus]38.383[minus]([minus]4.159)) vs. [minus]73.156 ([minus]214.022[minus] ([minus]52.449)), p = 0.023). It however had no significant effect on the QTc interval changes ([minus]0.005 ([minus]0.011 [minus] 0.003) vs. [minus]0.005 ([minus]0.015 [minus] 0.065) vs. [minus]0.021 ([minus]0.060[minus] ([minus]0.006)), p = 0.174). Conclusion The efficacy of pre-treatment with the methanol extract of Withania somnifera was comparable to that of pre-treatment with Neostigmine a commonly used carbamate drug. Thus, it is a potentially viable low cost treatment option for organophosphate poisoning in resource-limited settings.