Azadirachta indica (Neem)
Azadirachta indica (Neem) Commonly known as Neem, it is one of the most important detoxicants in Ayurvedic medicine. It grows in the Indian subcontinent. All parts of the tree can be used. It is bitter and pungent smelling. Historically has been used both orally and topically for skin conditions, as an antiviral and antibacterial, to treat ulcers, dental plaques, as insect repellant and various other indications. Major Chemical Constituents: The major chemical constituents are terpenes, limonoids, nimbin, nimbinene, 6-desacetylnimbinene, nimbandiol, nimbolide, quercetin, ß-sitosterol, n-hexacosanol and nonacosane. Pharmacological Actions: Antiatherosclerotic and cardiovascular activity: 1, 2 In human clinical studies, Azadirachta indica lowered both cholesterol and LDL-cholesterol in patients. Administration of the mature leaf extract decreased serum cholesterol in rats and caused a dose-dependent hypotension in rabbits and guinea pigs possibly through smooth muscle relaxation. Antidiabetic activity: 3 Oral administration of leaf extract resulted in a significant decrease in blood glucose levels in both normoglycaemic and hyperglycaemic animals. Anxiolytic activity: 4 A single dose of freshly prepared Azadirachta indica leaf extract produced a significant anxiolytic effect in both maze and open field tests. Anti-inflammatory activity: 5 Oral administration of 800 mg/kg of a 75% methanolic extract of bark and leaf produced inhibition of carrageenan-induced edema in rats. Nimbidin, the bitter principal from the seed oil consisting of limonoids, exhibited a dose–dependent inhibition of carrageenan-induced edema. Mast cell stabilizer / anti-itching activity: 6 Azadirachta indica leaf aqueous extract can reduce ulceration by preventing mast cell degranulation. Herb Drug interactions: Azadirachta indica has been reported to induce hepatotoxicity in rats if used with acetaminophen. One of the studies showed that Azadirachta indica has hypotensive effect, so it should be used cautiously with other hypotensive agents. Based on animal study, Azadirachta indica may decrease glucose levels and caution is advised when using concomitantly with other sugar-altering herbs and supplements. Safety: No health hazards or side effects are known in conjunction with the proper administration of designated therapeutic dosages. References: • Chattopadhyay RR. Effect of Azadirachta indica hydroalcoholic leaf extract on the cardiovascular system General Pharmacology: The Vascular System. 1997; 28(3): 449-451. • Pillai NR, Santhakumari G. Antiarthritic and anti-inflammatory actions of nimbidin. Planta Medica. 1981; 43:59. • Khosla P, Bhanwra S, Singh J, Seth S, Srivastava RK. A study of hypoglycaemic effects of Azadirachta indica (Neem) in normal and alloxan-diabetic rabbits. Indian Journal of Physiology and Pharmacology. 2000; 44(1): 69. • Jaiswal AK, Bhattacharya SK, Acharya SB. Anxiolytic activity of Azadirachta indica leaf extract in rats. Indian Journal of Experimental Biology. 1994; 32(7): 489. • Okpanyi SN, Ezeukwu GC. Anti-inflammatory and antipyretic activities of Azadirachta indica. Planta Medica. 1981; 41:34. • Chattopadhyay I, Nandi B, Chatterjee R, Biswas K, Bandyopadhyay U, Banerjee RK. Mechanism of antiulcer effect of Neem (Azadirachta indica) leaf extract: effect on H+-K+-ATPase, oxidative damage and apoptosis Inflammo-pharmacology. 2004; 12(2): 153–176 • Bhanwra S, Singh S, Singh J, Khosla P. Effect of Azadirachta indica (Neem) leaf aqueous extract on paracetamol-induced liver damage in rats. Indian J Physiol Pharmacol. 2000; 44(1): 64-8 • Koley KM, Lal J. Pharmacological effects of Azadirachta indica (neem) leaf extract on the ECG and blood pressure of rat. Indian J Physiol Pharmacol. 1994; 38(3): 223-5. • Sinniah D, Schwartz PH, Mitchell RA, Arcinue EL. Investigation of an animal model of a Reye-like syndrome caused by Margosa oil. Pediatr Res. 1985 Dec; 19(12): 1346-55.