Goal of the Review In this review, we examine the significance of nitric oxide (NO) and summaries the research on the relationship between cardiovascular disease (CVD) and cognitive impairment. The (NO) route is a mode of causation. recent discoveries Epidemiological studies have found evidence linking midlife CVD and related risk factors to an increased risk of dementia and cognitive decline later in life. The cause of this association is unknown, but risk may be communicated by an increase in neuro degeneration (such as amyloid deposition), vascular changes (such as small vessel disease), and mechanistically due to increased levels of oxidative stress and inflammation as well as changes in NO bioavailability. Among the groups of the rats fed on fennel and green tea 9:1 (G4; 16.21 ± 0.54 μM) slightly reduced the NO level in serum, compared with that, group fed on fennel and green tea 4:1 (G5; 14.14 ± 0.81 μM). Obtained results showed fennel with green tea as ratio 4:1 have a significant activity as antitumor agents against the tested human hepatocellular liver carcinoma cell lines without effect on normal cells. This study characterizes antioxidant activity and phenolic compounds of traditional medicinal plants associated with antioxidant, the improved ABTS•+ DPPH method was used to systematically assess the total antioxidant capacity.