In vitro screening of Mexican arnica (Heterotheca inuloides Cass.) inhibitory activity of the angiotensin converting enzyme as a hypotensive mechanism

The high incidence of cardiovascular diseases has become a major public health problem worldwide, and hypertension highly first. The renin-angiotensin-aldosterone system is one of the main routes of blood pressure regulation, and for this reason, inhibition of the angiotensin-converting enzyme has become a fundamental target for regulation and control of hypertension. Today, the search for treatment has turned to natural products. Heterotheca inuloides Cass., Mexican arnica, has high concentrations of phenolic compounds such as flavonoids, which have been correlated with free radical scavenging capacity (FRSC) and angiotensin converting enzyme inhibitory capacity (ACEI) as a hypotension mechanism. This study aimed to determine FRSC, ACEI and flavonoids of extracts of the H. inuloides shoot. Leaves had the highest concentration of total phenolic compounds (3177.85 mg gallic acid equivalents/100 g dry plant) and the highest concentration of total flavonoids (3896.47 mg total/100 g dp); outstanding were high concentrations of quercetin (706.68 mg/100 g dp) and kaempferol (39.22 mg/100 g dp). Regarding the FRSC of tested radicals, the behavior of the extracts was proportional to the content of phenolic compounds. Regarding ACEI capacity, compared with 90% inhibition by Captopril (2.5 mg/ mL), the extracts inhibited 50-70%, with no significant statistical difference. The high FRSC and ACEI capacities of the shoot make this plant an alternative in preventing cardiovascular problems associated with oxidative stress and hypertension.

Automated summary

The study found that extracts from Heterotheca inuloides Cass., Mexican arnica, have high antioxidant and angiotensin-converting enzyme inhibition capacities, which could play an important role in preventing cardiovascular issues and hypertension.