Int. J. Pharm. Sci. Rev. Res., 29(2), November – December 2014; Article No. 13, Pages: 67-71 ISSN 0976 – 044X International Journal of Pharmaceutical Sciences Review and Research Available online at www.globalresearchonline.net © Copyright protected. Unauthorised republication, reproduction, distribution, dissemination and copying of this document in whole or in part is strictly prohibited. 67 Debasish Bandyopadhyay 1* #, Debosree Ghosh 1 , Aindrila Chattopadhyay 2 1 Department of Physiology, University of Calcutta, University College of Science and Technology, 92, APC Road, Kolkata, India. 2 Department of Physiology, Vidyasagar College, 39, Sankar Ghosh Lane, Kolkata, India. #Principal Investigator, Centre with Potential for Excellence in a Particular Area (CPEPA), University of Calcutta, University College of Science and Technology, 92 APC Road, Kolkata, India. * Corresponding author’s E-mail: debasish63@gmail.com Accepted on: 26-09-2014; Finalized on: 30-11-2014. ABSTRACT Lead is a naturally occurring toxic element. It has several industrial uses and is highly toxic for living organisms if it enters and accumulates in body. Long term exposure to this heavy metal either environmentally or occupationally may cause various types of ailments among which myocardial injury and hepato-toxicity are worth mentioning. Lead induced myocardial injury occurs primarily through lead mediated oxidative damage of myocardial tissue. Lead stimulates generation of reactive oxygen species (ROS) which causes biochemical, cytological and physiological detrimental alterations of the cardiac tissue. Administration or supplementation of antioxidant rich aqueous curry leaves (a popular spice herb, Murraya koenigii) extract and melatonin, a natural indole, separately have the potentiality to provide protection against lead induced myocardial damage. Their combination can provide a stronger protection against myocardial damage brought about following exposure to lead and the protection is almost complete. Thus, we can think of designing a potent drug formulation with very low or no toxicity against lead induced oxidative stress mediated myocardial injury using aqueous curry leaves extract and melatonin in combination which may have future therapeutic relevance. Keywords: Lead, Myocardial injury, toxic element. INTRODUCTION n spite of marked therapeutic advancement, cardiac ailments are still remaining to be one of the significant causes of death of millions around the globe 1 . Mortality due to cardiac failure is more in developed countries and the rate is increasing in the developing countries like India 2 . The causes underneath such cardiovascular pathogenesis have been recognised to be many. Involvement of insulin resistance and diabetic cardiomyopathy 3 , altered lipid profile 5 , obesity, altered life style, dietary habits 6 have been found to be the major contributors. Molecular genomic study reveals genetic predisposition for cardiac arrest and ailments 7 . Environmental toxin induced oxidative stress mediated cardiac disorders and ischemic changes has been extensively evaluated and established in various models 8, 9 . Our studies also revealed the involvement of heavy metal induced oxidative stress mediated damage in cardiac tissues of male Wistar rats 10-13 . Lead is an old environment pollutant and the history of lead poisoning is almost 2500 years old 14 . Lead exposure occurs either environmentally or occupationally or by both routes 15 . Children are more susceptible to lead toxicity 16 . Chronic lead poisoning has been found to be associated with hypertension, altered lipid profile, arteriosclerosis and cardiac ailments 17 . Lead once absorbed and if not excreted enters and gets accumulated mainly in three types of tissues i.e., blood, soft tissues (liver, kidneys, brain, heart) and mineralizing tissues (bones and teeth) 18 . We have found through atomic absorption spectrophotometric studies that lead accumulated in the heart tissues and, lead induced oxidative stress plays a significant role in ischemic changes in heart 10, 11 and other organs as well 19 . We have also evaluated in vitro the involvement of oxidative stress in lead induced damages in heart 20 . We observed marked alterations in the activities of antioxidant enzymes in cardiac tissues following lead exposure in both in vitro and in vivo models 10, 11, 20 . The level of lead in blood has been found to be associated with increased blood pressure 21 . Most of the blood lead is known to be accumulated inside red blood cells 22 . The level of lead in bones has also been evaluated and found to be related with hepertension in individuals 23 . We found altered lipid profile and changes in blood parameters with lead acetate treatment of rats for seven consecutive days 24 . Hypertension and changes in lipid profile are considered as precursors of myocardial injuries 21, 22, 23 . M yocardial injury The myocardium is the muscular tissue of the heart. Myocardial injury can be of various types and may lead to various cardio-myopathic conditions i.e., arythmia, shock, necrosis, ischemia, infarction and failure 25 . The myocardium is supplied blood by the two major coronary arteries and their branches. Blockage of any of these blood vessels is accounted as one of the prime cause of myocardial infarction. Occlusion or blockage of any of these coronary vessels may result as a cause of clotting of blood or due to deposition of cholesterol inside blood vessel which ultimately narrows the vessel, lessens its elasticity and leads to blood clotting inside vessel. Inadequate or Lead induced Oxidative Stress M ediated M yocardial Injury: A Review I Review Article