Indian Journal of Experimental Biology Vol. 54, October 2016, pp. 670-675 Effect of ethanolic extract of Cyperus rotundus L. against isoprenaline induced cardiotoxicity Sadiya Khwaja* ,# , Tarique Mahmood* & Hefazat H Siddiqui Faculty of Pharmacy, Integral University, Kursi Road, Lucknow-226 026, Uttar Pradesh, India Received 02 March 2014; revised 01 June 2015 Interruption of blood supply to heart results in acute myocardial infarction (AMI) and further leads to damaging of the heart muscles. Available drugs for the treatment MI have one or other side effects, and there is a need for development of better alternative drugs. Here comes the role of herbal sources. In this study, we evaluated cardioprotective effect of Cyperus rotundus on isoprenaline-induced myocardial infarction. Thirty five Wistar rats, aged 60-100 days with body wt. 150-200 g, pretreated with ethanolic extract of Cyperus rotundus L. (@ 250 and 500 mg/kg body wt.) orally before induction of myocardial necrosis by administrating isoprenaline (85 mg/kg, s.c.) on 19 th and 20 th day of the pretreatment period. The treated rats were examined for gross functioning of heart, heart weight/body wt. Ratio, and also observed histopathologically. Further, activities of various cardiac enzymes such as aspartate transaminase, alanine transaminase, creatinine kinase-myoglobulin, lactate dehydrogenase, and the gold marker troponin-I were also determined. The levels altered by isoproterenol were found to be restored significantly by the test extracts especially at higher dose. Biochemical observations viz., serum ALT (P <0.0001), AST (P <0.0001), creatine kinase-myoglobulin (CK-MB) (P <0.0001), LDH (P <0.0001) demonstrated significant cardioprotective activity of the ethanolic extract of C. rotundus (500 mg/kg body wt.), against isoprenaline induced myocardial infarction. These results were also substantiated by physical parameters and histopathological observations. All these results were comparable with that of two standard drugs metoprolol (10 mg/kg/day), ramipril (3 mg/kg/day) as well as polyherbal formulation Abana (50 mg/kg/day). Keywords: Abana, Ayurveda, Cardiac markers, Cardioprotective, Coco-grass, Herbal drugs, Motha, Myocardial necrosis, Nut grass, Unani Myocardial infarction (MI) or acute myocardial infarction (AMI), commonly known as heart attack, results from the interruption of blood supply to a part of the heart, causing damage to the heart muscles. Though there are many drugs available for the treatment of MI, the side effects of such drugs have encouraged researchers to look for safe alternative herbal sources. In this context, drugs from natural sources, plants in particular, are considered safer with comparatively lesser or nil adverse effects 1-3 . Considerable research has gone into plants with promising activities from time to time. The coco-grass or nut grass, Cyperus rotundus L. is one such plant, well-known in both Unani and Ayurveda for various potential including cardioprotective activity. Locally called Motha, C. rotundus is known for its analgesic, antiarthritic, antidiabetic, antidiarrhoeal, anti-inflammatory, antimicrobial, antimutagenic, antioxidant, antipyretic, apoptotic as well as cytoprotective, potential in traditional system of medicine 4 . In Ayurveda, C. rotundus is reported for treatment of blood diseases and obesity 3 . The tubers of the plant have reported to possess antioxidant, free radical scavenging, hypolipidemic and hypotensive properties 4,5 . Isoprenaline (ISO), a catecholamine, is a synthetic β-adrenergic agonist that causes severe stress in the myocardium and causes necrosis in the heart muscle 6 . In this study ISO was used to induce myocardial infarction as it serves as a standard model to study the beneficial effect of many drugs on cardiac function 7,8 . ISO-induced myocardial necrosis showed membrane permeability alterations, which bring about the loss of function and integrity of myocardial membranes 7,8 . Here, we studied the cardioprotective activity of ethanolic extract of rhizomes of Cyperus rotundus 7,8 and the comparative evaluation of the rhizomes of the plant extract against some of the clinically established drugs, such as metoprolol, a selective β1 receptor blocker, ramipril, an angiotensin-converting enzyme —————— *Correspondence: E-mail: sadiyakhwaja89@gmail.com (SK); ansaritariq79@yahoo.co.in (TM) # Present add.: Medicinal Chemistry Division, CSIR-CIMAP, Lucknow, Uttar Pradesh, India