Effect of contaminated diet with a plant growth regulator “1-methylcyclopropene” on the hematological parameters and liver function of albino Wistar rats

Plant growth regulators (PGRs) play a vital role in optimizing plant development and harvest quality. However, excessive use can lead to the accumulation of residues on plants, posing a risk to the consumer health. The current study focuses on 1-methylcyclopropene (1-MCP), an emerging PGR used for the last 20 years to reduce post-harvest and increase the shelf life up to several months. The aim of our research is to investigate the effect of the 1-MCP residue exposure on mammalian tissues. To do so, we evaluated the effect of the consumption of 1-MCP-contaminated diet on the liver function, antioxidant system, and hematopoietic parameters of albino Wistar rats for a period of 90 days. Rats were fed with whether a control diet (group I) or a contaminated diet with two respective doses of 1-MCP (D1 for group I and D2 for group II). At the end of the experiment, we conducted a CBC, we measured the body and liver weight, the biochemical liver biomarkers (AST and ALT serum activities), the antioxidant system (GSH content, GST, GPx, CAT, and SOD activities) as well as the lipid peroxidation end-product (MDA levels), and we also calculated the OSI and conducted H&E stained sections to observe the histopathological changes of the liver. The results revealed that the contaminated diet with the lowest dose of 1-MCP increased significantly the WBC count and MCV and altered the PLT count and P-LCR suggesting a leucocytosis and macrocytic anemia. 1-MCP also induced oxidative stress in the liver and depleted the general enzymatic activity of the anti-oxidative system including GST, GPx, CAT, and SOD and the OSI of the 1-MCP treated rats was significantly elevated. 1-MCP also elevated MDA levels but with no observable pathological changes in the hepatocytes or modified AST and ALT serum levels. Although exposure to 1-MCP through the diet may contain antioxidants that can potentially reduce the toxic effect, the risk of significant health implications discovered in this research cannot be ignored. Further investigation into the effects of 1-MCP when directly ingested or inhaled, targeting multiple mammalian tissues and understanding its mode of action on a molecular level, would be valuable in designing safety guidelines and healthcare measures, especially for farmworkers who are in direct contact with 1-MCP.