Subchronic oral toxicity and in vitro anti-neuroinflammatory evaluation of Ficus erecta leaves extract for potential functional food applications

Abstract

Ficus erecta leaves, a traditional medicinal plant that is widely used in East Asia, have demonstrated promising cognitive-enhancing effects. However, the safety of its long-term administration has not been elucidated. Therefore, we evaluated the subchronic toxicity of an ethanol extract of F. erecta leaves (EEFE) by conducting 13-week repeated oral toxicity study using Sprague–Dawley (SD) rats. Male and female rats were administered EEFE at doses of 0, 500, 1000, or 2000 mg/kg/day. Clinical signs, body weight, food consumption, hematology, serum biochemistry, organ weights, and gross necropsy findings were also monitored. No treatment-related mortality or toxic effects were observed at any doses of EEFE. Accordingly, the No Observed Adverse Effect Level (NOAEL) was determined to be 2000 mg/kg/day for both sexes. Additionally, we observed anti-neuroinflammatory effects of EEFE and its active compound rutin in BV-2 microglia. EEFE and rutin significantly inhibited nitrate and prostaglandin E2 (PGE₂) production in BV-2 cells. These results support the safety and anti-inflammatory action of EEFE for further development as a candidate herbal therapeutic or functional food for improving cognitive health and age-related conditions.