Three species of Terminalia tree are used for several medicinal purposes: Terminalia arjuna, Terminalia bellerica, and Terminalia chebula. Terminalia arjuna is used in traditional Ayurvedic medicine to balance the three humors Vata, pitta, and Kapha. Arjuna is also effective against asthma, scorpion stings, poisonings, and bile duct disorders. This article will focus on the benefits of Arjuna bark for blood pressure problem.
What is High Blood Pressure?
Hypertension or high blood pressure is a common condition affecting more than 1 in 5 individuals worldwide. In hypertension, the pressure of the blood against the blood vessels is higher, increasing the risk to your overall health. If this becomes chronic, it can even increase your risk of heart attack or stroke. Blood pressure is diagnosed based on two measurements: systolic and diastolic. Systolic blood pressure is the pressure against the blood vessel during the heart contraction and diastolic pressure is pressure against the artery walls between heartbeats. The normal range is 120/80 mmHg and readings above 130/90 mmHg are considered as high. Fatty deposits on the lining of the blood vessel (atherogenesis), stress, and kidney disorders are some of the reason for hypertension. High blood pressure can alter the blood flow to the heart and cause ischemic injury to the heart muscles. Hypertensive heart disease is the leading cause of death associated with high blood pressure. Let us understand how Arjuna benefits for blood pressure and heart diseases associated with it.
Arjuna benefits for hypertension
Terminalia arjuna or arjuna belongs to the family Combretaceae. Use of Arjuna for Chest pain, congestive heart failure, and dyslipidemia is described in various Indian medical texts like Sushruta Samhita, Ashtanga Hridayam, and Charaka Samhita. Vagabhatta was the first individual who advocated the use of Arjuna bark powder for heart ailments.
This bark is seen to possess antioxidant, hypolipidemic, antiatherogenic, and anti-ischemic properties. Some of the important phytoconstituents with medicinal benefits are β-sitosterol, flavonoids, triterpenoids, and glycosides.
Mechanisms by which Arjuna is beneficial for hypertension
- Effects on the heart and blood pressure
Arjuna is seen to have diuretic, inotropic (increasing the strength of muscle contraction), and chronotropic (altering heart rate) properties. It increases the blood flow through the heart and strengthens cardiac muscle contraction. Administering alcoholic and aqueous bark extract intravenously to dogs, resulting in a decrease in blood pressure.
Antioxidant and cardioprotective properties
Oxidative stress causes proliferation of smooth muscles of the blood vessels and collagen deposits thickening the vascular lining and narrowing the blood vessel lumen. Oxidative stress also affects the contractibility of the blood vessels resulting in hypertension. Antioxidants neutralize these effects and prevent tissue injury.
The dried bark is seen to enhance endogenous antioxidant compounds of the heart and prevent oxidative stress resulting in the ischemic injury of the heart. Also, an alcoholic extract of Arjuna triggers the production of heat shock protein from the heart muscles (myocardium) that offers protection against oxidative stress. Research suggests that methanol extract of the bark has the highest flavonoid and phenolic content that has the maximum antioxidant property. Cardioprotective effect of Arjuna is comparable to Fluvastatin (a medicine used to prevent heart disease and lower cholesterol levels). Moreover, triterpenoids derived from Arjuna extract protects the heart by boosting the endogenous antioxidant defense system. Antioxidant and cardioprotective properties are responsible for the benefits of Arjuna for Heart disease.
- Lowers cholesterol levels
Animal experiments have shown that Arjuna bark extract reduces the triglyceride and total cholesterol levels. Ethanolic extract of the bark has a significant lipid-lowering effect and is seen to result in a decrease in the plasma levels of lipids in high-fat diet fed hamsters. The hypolipidemic action of Arjuna is due to the down-regulation of lipogenic enzymes and increased hepatic clearance of cholesterol.