Hepatoprotective Effects and Antioxidant Properties of a Herbal Detoxifying Formula Against Chlorpyrifos-Induced Toxicity in Sprague-Dawley Rats

Chlorpyrifos (CPF), a widely used organophosphate pesticide, induces hepatotoxicity primarily through oxidative stress, acetylcholinesterase (AChE) inhibition, and inflammatory responses. This study evaluated the hepatoprotective potential of detoxifying formulations prepared from four medicinal plants, <i>Thunbergia laurifolia</i>, <i>Embelia sessiliflora</i>, <i>Morinda angustifolia</i>, and <i>Thunbergia coccinea</i>, in various ratios. Among these, a formulation composed of <i>T. laurifolia</i> and <i>E. sessiliflora</i> (1:1; Formula 04) showed the highest activity, with rosmarinic acid identified by compact mass spectrometry (CMS). Formula 04 demonstrated the greatest antioxidant and pro-apoptotic potential among the seven tested formulations, as confirmed by in vitro DPPH and superoxide radical assays and apoptosis assays in hepatic stellate LX-2 cells. In vivo, Sprague-Dawley rats exposed to CPF (16 mg/kg/day, oral gavage) received Formula 04 orally 30 min prior to CPF exposure in 6 cyclic dosing regimen for 18 days. The treatment restored AChE activity, increased superoxide dismutase levels, reduced glutathione levels, and decreased malondialdehyde, indicating attenuation of oxidative stress. Serum AST levels were significantly reduced compared with the CPF group, and histopathology revealed that the hepatic architecture was preserved. These findings demonstrate that Formula 04 exerts hepatoprotective effects against CPF-induced toxicity via redox regulation and cellular protection mechanisms, demonstrating its potential as a natural detoxifying agent.