Impact of Ficus deltoidea Aqueous Extract on Maternal Hepatic Drug Metabolism and Foetal Development in Rats

The present study aimed to assess the potential maternal toxicity of Ficus deltoidea var. kunstleri aqueous extract in pregnant rats, along with its impact on maternal hepatic drug metabolism and foetal skeletal development. Pregnant rats were divided into five groups and orally administered varying doses of F. deltoidea aqueous extract (0, 250, 500, 1000, and 2000 mg/kg body weight) from gestation day 6 to 20. Throughout the administration period, clinical observations, body weight, and food and water intake were monitored. On gestation day 21, the pregnant rats were sacrificed, and their vital organs and foetuses were collected for analysis. Gene expression related to hepatic drug metabolism was evaluated using the RT2 Profiler™ PCR array. Foetal external morphology was examined for abnormalities, and skeletal structures were stained with Alizarin Red to assess the effects of F. deltoidea aqueous extract on bone ossification during organogenesis. No maternal toxicity was observed, except for a significant increase in liver weight in the treated groups (p < 0.05). Analysis of 84 genes revealed significant changes in 15, 4, and 11 genes in the 250, 500, and 2000 mg/kg body weight groups, respectively. Notably, Gpx5 and Pkm, both phase II metabolising enzyme genes were downregulated in a dose-dependent manner. Despite some skeletal variations, the extract did not induce foetal external malformations or skeletal abnormalities. The significant increase in maternal liver weight, together with the downregulation of Gpx5 and Pkm, suggests an adaptive hepatic response to the extract rather than an adverse effect. These findings also suggest that F. deltoidea var. kunstleri aqueous extract does not cause embryo toxicity, foetal growth retardation, or developmental malformations, particularly in skeletal formation. The developmental no-observed-adverse-effect level (NOAEL) was determined to be >2000 mg/kg/day via oral administration. Further research is warranted to explore the synergistic interactions of genes involved in hepatic drug metabolism in response to the extract.