Evaluation of cardioprotective phytochemicals from Phyllanthus maderaspatensis L. using in vitro, in vivo and in silico approach

The purpose of this study was to assess the cardioprotective potential of Phyllanthus maderaspatensis L. Quantitative phytochemical analysis and gas chromatography-mass spectrometry (GC-MS) of solvent extracts were performed. Standard antioxidant assays were used to determine the free-radical scavenging activity of the leaf extract. An in vivo experiment using isoproterenol (ISO)-treated rats was conducted to assess the effect of the plant extract on cardioprotective biomarkers. A significant dose-dependent increase in total antioxidant activity of the extract was observed. At 50 µg, 19–24 % scavenging activity was recorded, whereas at 400 µg, 79–84 % scavenging activity was observed. Rats receiving the extract showed a reduction in heart weight and an increase in body weight. The mean serum concentration of cardiac troponin (cTn) T/I in rats treated with the standard drug was effectively reduced (1.13 ± 0.07/0.64 ± 0.05 ng mL-1), whereas it was comparably reduced by the extract (1.25 ± 0.19/0.72 ± 0.08 ng mL-1). Creatine kinase MB (CK-MB) of the standard was significant at 78.33 ± 6.26 IU and the extract was 83.35 ± 7.51 IU. The data showed increased values among the standard and extract compared to the control group but were found to be significantly (p <0.001) decreased among the treated groups. Compared to negative control animals (healthy rats), ISO-treated rats exhibited significantly increased levels of aspartate myocardial cell damage. After 5 weeks of treatment, in comparison to those in the positive control (PC), extract-treated rats had significantly (p <0.05) elevated levels of serum AST, alanine transaminase (ALT), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH). Recovery from ISO-induced electrophysiological abnormalities was confirmed by decreased serum cardioprotective markers, mainly troponin and CK-MB. Histopathological damage to cardiac tissues was significantly reduced, with values approaching those of the control and standard drug-treated groups, particularly at a dose of 200 mg kg-1 body weight (bwt). The findings confirm that the cardioprotective effects are primarily attributable to the presence of antioxidant constituents present in the extract of P. maderaspatensis.