Yerramilli Vimala

Background: Argemone mexicana, commonly known as prickly poppy, belongs to the Papaveraceae family and has several medicinal properties. Liver plays a significant role in the secretion of vitamins, cholesterol and glycogen and also metabolises carbohydrates, lipids, protein and detoxifies the xenobiotics. Aim: This study revealed the antioxidant and hepatoprotective efficacy of the motherplant (stem) and stem callus of A. mexicana. Methods: The callus initiation of the stem explant was obtained at the concentration of 1.0mg/L N NAA +0.5mg/L BAP and 0.5mg/L IAA +1.0mg/L Kn with MS medium. Methanolic extracts of the stem and callus of A. mexicana were evaluated against CCl4-induced toxicity in albino Wistar rats. Results: The present study deals with the hepato-restorative activity exhibited by methanolic extracts of A. mexicana stem and their corresponding callus against CCl4-intoxicated albino Wistar rats (1.5 ml/kg bw) and also identified various phytocompounds through GC-MS profiling, which may be responsible for the restorative activity from hepatic-toxicity. The study demonstrated that A. mexicana stem and callus methanolic extracts have hepatoprotective potential at 180mg/kg bw treatment with reference to standard (silymarin 100mg/kg bw), showing a marked decline in CCl4-induced increase in SGPT (Serum Glutamic Pyruvic Transaminase), SGOT (Serum Glutamic Oxaloacetic Transaminase), ALP (Alkaline Phosphatase), Total bilirubin and rise in CCl4-induced decrease in Total protein compared to normal control and standard (Silymarin). Histopathology also confirmed the recovery from hepatotoxicity by treatment with standard or with stem and callus extracts of A. mexicana. Conclusion: The present study revealed the antioxidant and hepato-restorative potential of methanolic extracts of the stem and stem callus against CCl4-induced toxicity in albino Wistar rats. The current study confirms its antioxidant and hepato-restorative potential against liver damage. These findings indicate a possible alternative cost-effective drug formulation to be developed after further experiments to identify specific compounds responsible for the restoration of the liver from potential damage. Major Finding: Methanolic extracts of the stem and callus of A. mexicana demonstrated hepatoprotective activity against CCl4-induced hepatotoxicity by reducing SGPT, SGOT, ALP, and TB, increasing TP, and gradually restoring normal liver tissue architecture.

Heavy metal (HM) stress is threatening agricultural crops, ecological systems, and human health worldwide. HM toxicity adversely affects plant growth, physiological processes, and crop productivity by disturbing cellular ionic balance, metabolic balance, cell membrane integrity, and protein and enzyme activities. Plants under HM stress intrinsically develop mechanisms to counter the adversities of HM but not prevent them. However, the exogenous application of abscisic acid (ABA) is a strategy for boosting the tolerance capacity of plants against HM toxicity by improving osmolyte accumulation and antioxidant machinery. ABA is an essential plant growth regulator that modulates various plant growth and metabolic processes, including seed development and germination, vegetative growth, stomatal regulation, flowering, and leaf senescence under diverse environmental conditions. This review summarizes ABA biosynthesis, signaling, transport, and catabolism in plant tissues and the adverse effects of HM stress on crop plants. Moreover, we describe the role of ABA in mitigating HM stress and elucidating the interplay of ABA with other plant growth regulators.