Effect of nori, a combination of turmeric (Curcuma longa) and gotu kola (Centella Asiatica) on blood pressure, modulation of ACE, eNOS and iNOS gene expression in hypertensive rats

Abstract

Hypertension is a major risk factor for causing life-threatening cardiovascular diseases such as myocardial infarction, coronary heart failure, kidney failure, and stroke. Its cases continue to increase worldwide and it is estimated that 1.56 billion adults would live with the condition in 2025. Therefore, this study aims to examine the antihypertensive effect of nori supplement prepared with a combination of turmeric (Curcuma longa) and gotu kola (Centella Asiatica) on L-NAME-induced and non-induced rats. It was conducted for 28 days on 25 wistar rats that were randomly assigned to the negative, positive, comparison, supplement, and test control groups. CODA was then used in measuring the blood pressure of the rats, while ECG and PPG sensors were utilized for arterial stiffness assessment, as well as for spatial QRS-T and heart rate analysis. Additionally, serum NO levels were measured using griess reagents by spectrophotometric λ540 nm. At the same time, the gel-based PCR semi-quantitative method was used in assessing the activity of ACE, including eNOS and iNOS gene expression. The results showed that nori preparations which contained a combination of 5% turmeric and gotu kola in a feed mixture, had an antihypertensive effect. The effect was characterized by a decrease in systolic, diastolic, and mean arterial blood pressure, as well as heart rate, arterial stiffness, and spatial QRS-T. Additionally, it occurred due to increased NO availability, which resulted from eNOS expression as well as a decrease in iNOS and ACE expression.