Impact of Green-Synthesized Silver Nanoparticle in Wistar Rats: Behavioral, Biochemical, And Histopathological Insights from Acute and Sub-Acute Oral Exposure.

Acalypha paniculata (AP) is a subshrub traditionally used in ethnomedicine for treating skin diseases, asthma, and inflammatory conditions. This study focuses on the eco-friendly synthesis and characterization of silver nanoparticles derived from the Acalypha paniculata herb. The safety profile of Acalypha paniculata-based silver nanoparticles (APSN), particularly regarding behavioral, biochemical, and histopathological aspects, has not been thoroughly investigated. This study evaluated the acute and sub-acute toxicity of APSN in rats, adhering to OECD guidelines. Four groups of six rats each received a single oral dose of APSN at 500, 1000, and 2000 mg/kg. Post-administration, the rats were monitored for thirteen signs of general toxicity over four hours and assessed for motor and locomotive behavior using a rota rod and open field test on the 14^th day. In repeated- dose toxicity studies, four groups of six rats each were administered 500, 1000, and 2000 mg/kg APSN daily for 28 days. Parameters such as feed intake, body weight, biochemical and hematological profiles, and organ histopathology were studied. The results of the acute toxicity studies indicated no evident signs of toxicity, including abnormal motor locomotion and behavior. The rats exhibited good tolerance across the three doses. However, sub-acute exposure at 2g/kg showed minor morphological changes in liver histopathology, evidenced by minimal hepatic cell infiltration. The oral no-observed-adverse-effect-level (NOAEL) exceeded 2000 mg/kg/day in both male and female Wistar rats, confirming the safety of APSN when administered orally. This study supports the ethnomedicinal claim of APSN, though further clinical studies are necessary to confirm these findings and ensure comprehensive safety validation.