Arjuna is a single-herb formulation prepared from the bark extract of Arjuna (Terminalia arjuna). Arjuna is known for its cardioprotective action and is recommended in the management of various cardiovascular diseases as a co-prescription. Arjuna exerts positive inotropic effect on the atrial muscles by releasing noradrenaline. Tannins show normotensive effect mediated through cholinergic mechanism. The prostaglandin E2 (PGE2)-like activity of Arjuna produces coronary vasodilation, a Sealed pack of which increases coronary flow, decreases frequency of angina, decreases left ventricular mass, and improves left ventricular ejection fraction. The cardioprotective action of Arjuna is due to its endogenous antioxidant activity, lipid peroxidation inhibiting activity, and cytokine level-modulating activity.
Pharmacological Actions
1. Positive inotropic activity
Arjuna exerts a positive inotropic effect on atrial muscles. Hydrophilic constituents of T arjuna are essential to its inotropic therapy. Increased release of noradrenaline from sympathetic nerve endings is said to be the underlying mechanism for Arjuna induced positive inotropy in atrial muscles. The inotropic effect of Tarjuna is attributable primarily to enhancing sarcoplasmic reticular (SR) function. The significance of Tarjuna-induced increase in both SR Ca²+ release and uptake is that such actions stabilize intracellular Ca²+ cycling and minimize the change in contraction duration while enhancing contractility on the beat-to-beat basis.
2. Antihypertensive activity
Tannins and tannin-related compounds are thought to be the contributing factors to the reported hypotensive action of Arjuna. The hypotensive effect of these compounds is mediated by cholinergic mechanisms. Administration of T arjuna produced a dose-dependent, sustained fall of blood pressure; its response to various neurohumoral agents such as acetylcholine, adrenaline, and niacin suggests that the drug acts by modifying the autonomic responses in the body
3. Coronary vasodilatory activity
The PGE2-like activity of Arjuna is known to produce coronary vasodilation, which explains the pharmacological basis of the increased coronary flow. T arjuna brings about a rise in the force of contraction and bradycardia, a trend toward an increase in the coronary flow. The enhancement of PGE2-like activity by T arjuna accounts for the rise in coronary flow. Thus, Tarjuna can be a useful agent in the management of congestive heart failure (CHF).
4. Cardioprotective activity
Prophylactic and therapeutic treatment with Arjuna improves altered hemodynamic, biochemical, and histopathological parameters in CHF, suggesting its cardioprotective action. T arjuna appears to preserve left ventricular function as evidenced by significant restoration of left ventricular pressure (LV [dP/dt] max and LV [dP/dt] min) and restoration of elevated left ventricular end-diastolic pressure (LVEDP). An increase in LV (dP/dt) max and LV (dp/dt) min reflects an overall enhancement of myocardial contractility and relaxation, suggesting improvement in left ventricular dysfunction. Reduction in LVEDP implies that there is an increase in blood flow through the subendocardial region of the heart that bears the maximum brunt of the ischemic insult. Under ischemic conditions, there is a disproportionate reduction in blood flow to the subendocardial regions of the heart, which is subjected to the greatest extravascular compression during systole. Thus, Tarjuna may indirectly aid in restoring the blood flow to normal levels in these regions by reducing the elevated LVEDP. The cardioprotective action of Tarjuna has significant: prophylactic and therapeutic benefits-it prevents CHF, possibly through maintaining endogenous antioxidant enzyme activities, inhibiting lipid on peroxidation, and regulating cytokine levels.
5. Antianginal activity
Arjuna administered to patients with postmyocardial infarction angina has resulted in decreased frequency of angina, decreased left ventricular mass, and improvement in left ventricular ejection fraction."
6. Platelet aggregation-inhibitory activity
Superoxide generation increases platelet reactivity and limits the biological activity of nitric oxide. The inhibitory action of nitric oxide on aggregation of platelets as well as their adhesion to the endothelium, induced by thrombin, is potentiated by superoxide dismutase (SOD) consistent with preventing the inactivation of endothelium-derived nitric oxid. Oleanane-type triterpene glycosides designated as termiarjunoside I and termiarjunoside Il potently suppress the superoxide production by phagocytosing macrophages and also inhibit aggregation of platelets.
7. Antihyperlipidemic activity
Arjuna is found to be the most potent hypolipidemic agent. It induces partial inhibition of atheroma. Arjuna acts by inhibiting lipid implantation into the injured arterial wall and proliferation of smooth muscle cells. T arjuna is also effective in bringing down the atheromatous plaque size. The hypocholesterolemic action of Arjuna is mediated through increased cholesterol excretion in the feces.
8. Antioxidant activity
Flavonoids of Arjuna have been reported to exert antioxidant activity. Treatment with T arjuna increases the levels of antioxidant enzymes such as SOD and glutathione (GSH). SOD is a highly effective antioxidant enzyme and is responsible for catalytic disputation of highly reactive and potentially toxic superoxide radicals to hydrogen peroxide (H₂O₂). The H₂O, is further metabolized either by catalase or peroxidase, and GSH acts as a scavenger.
Arjuna contains several chemical constituents such as arjunetin, arjunolic acid, arjunic acid, arjungenin, and their glucosides, arjunglucoside 2, and tannins.
Indications
Co-prescription in
- Prehypertension
- Hypertension
- Stable angina pectoris
- Ischemic heart disease
Due to the lack of safety data, the use of Lasuna during pregnancy and lactation is not recommended
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