Ameliorative Effects of Moringa oleifera Aqueous Leaf Extract on Dichlorvos-Induced Interstitial Pneumonitis in Wistar Rats

Background: Insecticide poisoning is the most common cause of lung diseases among people with insecticide-related occupations which has significant morbidity and mortality if left untreated. This study aimed to investigate the effects of aqueous leaf extract of Moringa oleifera on dichlorvos-induced interstitial pneumonitis in the adult Wistar rat.Methods: Thirty (30) adult Wistar rats (male and female) weighing between 240 g and 270 g were divided into five (5) groups of six (6) rats per group. Group A rats were placed on feed and water only. Group B rats were exposed to only 2 puffs of dichlorvos (10 ml/puff) at a concentration of 100 mg/m3, administered at 10 am daily for 30 minutes via inhalation. Group C rats received 500mg/kg body weight per day (BWT/D) of Moringa oleifera. Groups D and E rats were exposed to dichlorvos via inhalation and received 250mg/kg BWT/D (low dose) and 500mg/kg BWT/D (high dose) of Moringa oleifera respectively. The Moringa oleifera dosages were given for 30 consecutive days via an orogastric tube. The weights of the animas in each group were taken and recorded weekly and the difference noted. At the end of the 30th day exposure, the animals were euthanized under chloroform anaesthesia and the lungs were harvested and processed for histological examination. The obtained data were analyzed using the one-way Analysis of Variance, with level of significance set at <0.05. Results: Exposure to dichlorvos did not affect body weight in rats, but it did cause significant changes in blood parameters, including decresed lymphocytes and red blood cells, and disruptions of other red cell indices, indicating haematoogical toxicity. This suggests that dichlorvos may have effects of the bood and haematoogical system, even if it doesn’t affect body werght. The histological sections of the lungs of rats in Group A, C, D and E showed normal histoarchitecture of the lungs. There were observable histological variations in the lung histoarchitecture of the exposed rats (Group B) which include bronchiolar haemorrhage, alveolar haemorrhage and interstitial infiltrates of inflammatory cells (evidence of interstitial pneumonitis).Conclusion: It was concluded that Moringa oleifera had an ameliorative effect on dichlorvos-induced interstitial pneumonitis in Wistar rats. Moringa oleifera is therefore valuable in combating interstitial pneumonitis.